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Archive for the ‘BioPrinting in Regenerative Medicine’ Category

Human Factor Engineering: New Regulations Impact Drug Delivery, Device Design And Human Interaction

Curator: Stephen J. Williams, Ph.D.

Institute of Medicine report brought medical errors to the forefront of healthcare and the American public (Kohn, Corrigan, & Donaldson, 1999) and  estimated that between

44,000 and 98,000 Americans die each year as a result of medical errors

An obstetric nurse connects a bag of pain medication intended for an epidural catheter to the mother’s intravenous (IV) line, resulting in a fatal cardiac arrest. Newborns in a neonatal intensive care unit are given full-dose heparin instead of low-dose flushes, leading to threedeaths from intracranial bleeding. An elderly man experiences cardiac arrest while hospitalized, but when the code blue team arrives, they are unable to administer a potentially life-saving shock because the defibrillator pads and the defibrillator itself cannot be physically connected.

Human factors engineering is the discipline that attempts to identify and address these issues. It is the discipline that takes into account human strengths and limitations in the design of interactive systems that involve people, tools and technology, and work environments to ensure safety, effectiveness, and ease of use.

 

FDA says drug delivery devices need human factors validation testing

Several drug delivery devices are on a draft list of med tech that will be subject to a final guidance calling for the application of human factors and usability engineering to medical devices. The guidance calls called for validation testing of devices, to be collected through interviews, observation, knowledge testing, and in some cases, usability testing of a device under actual conditions of use. The drug delivery devices on the list include anesthesia machines, autoinjectors, dialysis systems, infusion pumps (including implanted ones), hemodialysis systems, insulin pumps and negative pressure wound therapy devices intended for home use. Studieshave consistently shown that patients struggle to properly use drug delivery devices such as autoinjectors, which are becoming increasingly prevalent due to the rise of self-administered injectable biologics. The trend toward home healthcare is another driver of usability issues on the patient side, while professionals sometimes struggle with unclear interfaces or instructions for use.

 

Humanfactors engineering, also called ergonomics, or human engineering, science dealing with the application of information on physical and psychological characteristics to the design of devices and systems for human use. ( for more detail see source@ Britannica.com)

The term human-factors engineering is used to designate equally a body of knowledge, a process, and a profession. As a body of knowledge, human-factors engineering is a collection of data and principles about human characteristics, capabilities, and limitations in relation to machines, jobs, and environments. As a process, it refers to the design of machines, machine systems, work methods, and environments to take into account the safety, comfort, and productiveness of human users and operators. As a profession, human-factors engineering includes a range of scientists and engineers from several disciplines that are concerned with individuals and small groups at work.

The terms human-factors engineering and human engineering are used interchangeably on the North American continent. In Europe, Japan, and most of the rest of the world the prevalent term is ergonomics, a word made up of the Greek words, ergon, meaning “work,” and nomos, meaning “law.” Despite minor differences in emphasis, the terms human-factors engineering and ergonomics may be considered synonymous. Human factors and human engineering were used in the 1920s and ’30s to refer to problems of human relations in industry, an older connotation that has gradually dropped out of use. Some small specialized groups prefer such labels as bioastronautics, biodynamics, bioengineering, and manned-systems technology; these represent special emphases whose differences are much smaller than the similarities in their aims and goals.

The data and principles of human-factors engineering are concerned with human performance, behaviour, and training in man-machine systems; the design and development of man-machine systems; and systems-related biological or medical research. Because of its broad scope, human-factors engineering draws upon parts of such social or physiological sciences as anatomy, anthropometry, applied physiology, environmental medicine, psychology, sociology, and toxicology, as well as parts of engineering, industrial design, and operations research.

source@ Britannica.com

The human-factors approach to design

Two general premises characterize the approach of the human-factors engineer in practical design work. The first is that the engineer must solve the problems of integrating humans into machine systems by rigorous scientific methods and not rely on logic, intuition, or common sense. In the past the typical engineer tended either to ignore the complex and unpredictable nature of human behaviour or to deal with it summarily with educated guesses. Human-factors engineers have tried to show that with appropriate techniques it is possible to identify man-machine mismatches and that it is usually possible to find workable solutions to these mismatches through the use of methods developed in the behavioral sciences.

The second important premise of the human-factors approach is that, typically, design decisions cannot be made without a great deal of trial and error. There are only a few thousand human-factors engineers out of the thousands of thousands of engineers in the world who are designing novel machines, machine systems, and environments much faster than behavioral scientists can accumulate data on how humans will respond to them. More problems, therefore, are created than there are ready answers for them, and the human-factors specialist is almost invariably forced to resort to trying things out with various degrees of rigour to find solutions. Thus, while human-factors engineering aims at substituting scientific method for guesswork, its specific techniques are usually empirical rather than theoretical.

HFgeneralpic

 

 

 

 

 

 

 

 

 

 

 

The Man-Machine Model: Human-factors engineers regard humans as an element in systems

The simple man-machine model provides a convenient way for organizing some of the major concerns of human engineering: the selection and design of machine displays and controls; the layout and design of workplaces; design for maintainability; and the work environment.

Components of the Man-Machine Model

  1. human operator first has to sense what is referred to as a machine display, a signal that tells him something about the condition or the functioning of the machine
  2. Having sensed the display, the operator interprets it, perhaps performs some computation, and reaches a decision. In so doing, the worker may use a number of human abilities, Psychologists commonly refer to these activities as higher mental functions; human-factors engineers generally refer to them as information processing.
  3. Having reached a decision, the human operator normally takes some action. This action is usually exercised on some kind of a control—a pushbutton, lever, crank, pedal, switch, or handle.
  4. action upon one or more of these controls exerts an influence on the machine and on its output, which in turn changes the display, so that the cycle is continuously repeated

 

Driving an automobile is a familiar example of a simple man-machine system. In driving, the operator receives inputs from outside the vehicle (sounds and visual cues from traffic, obstructions, and signals) and from displays inside the vehicle (such as the speedometer, fuel indicator, and temperature gauge). The driver continually evaluates this information, decides on courses of action, and translates those decisions into actions upon the vehicle’s controls—principally the accelerator, steering wheel, and brake. Finally, the driver is influenced by such environmental factors as noise, fumes, and temperature.

 

hfactorconsideroutcomes

How BD Uses Human Factors to Design Drug-Delivery Systems

Posted in Design Services by Jamie Hartford on August 30, 2013

 Human factors testing has been vital to the success of the company’s BD Physioject Disposable Autoinjector.

Improving the administration and compliance of drug delivery is a common lifecycle strategy employed to enhance short- and long-term product adoption in the biotechnology and pharmaceutical industries. With increased competition in the industry and heightened regulatory requirements for end-user safety, significant advances in product improvements have been achieved in the injectable market, for both healthcare professionals and patients. Injection devices that facilitate preparation, ease administration, and ensure safety are increasingly prevalent in the marketplace.

Traditionally, human factors engineering addresses individualized aspects of development for each self-injection device, including the following:

  • Task analysis and design.
  • Device evaluation and usability.
  • Patient acceptance, compliance, and concurrence.
  • Anticipated training and education requirements.
  • System resilience and failure.

To achieve this, human factors scientists and engineers study the disease, patient, and desired outcome across multiple domains, including cognitive and organizational psychology, industrial and systems engineering, human performance, and economic theory—including formative usability testing that starts with the exploratory stage of the device and continues through all stages of conceptual design. Validation testing performed with real users is conducted as the final stage of the process.

To design the BD Physioject Disposable Autoinjector System , BD conducted multiple human factors studies and clinical studies to assess all aspects of performance safety, efficiency, patient acceptance, and ease of use, including pain perception compared with prefilled syringes.5 The studies provided essential insights regarding the overall user-product interface and highlighted that patients had a strong and positive response to both the product design and the user experience.

As a result of human factors testing, the BD Physioject Disposable Autoinjector System provides multiple features designed to aide in patient safety and ease of use, allowing the patient to control the start of the injection once the autoinjector is placed on the skin and the cap is removed. Specific design features included in the BD Physioject Disposable Autoinjector System include the following:

  • Ergonomic design that is easy to handle and use, especially in patients with limited dexterity.
  • A 360° view of the drug and injection process, allowing the patient to confirm full dose delivery.
  • A simple, one-touch injection button for activation.
  • A hidden needle before and during injection to reduce needle-stick anxiety.
  • A protected needle before and after injection to reduce the risk of needle stick injury.

 

YouTube VIDEO: Integrating Human Factors Engineering (HFE) into Drug Delivery

 

Notes:

 

 

The following is a slideshare presentation on Parental Drug Delivery Issues in the Future

 The Dangers of Medical Devices

The FDA receives on average 100,000 medical device incident reports per year, and more than a third involve user error.

In an FDA recall study, 44% of medical device recalls are due to design problems, and user error is often linked to the poor design of a product.

Drug developers need to take safe drug dosage into consideration, and this consideration requires the application of thorough processes for Risk Management and Human Factors Engineering (HFE).

Although unintended, medical devices can sometimes harm patients or the people administering the healthcare. The potential harm arises from two main sources:

  1. failure of the device and
  2. actions of the user or user-related errors. A number of factors can lead to these user-induced errors, including medical devices are often used under stressful conditions and users may think differently than the device designer.

Human Factors: Identifying the Root Causes of Use Errors

Instead of blaming test participants for use errors, look more carefully at your device’s design.

Great posting on reasons typical design flaws creep up in medical devices and where a company should integrate fixes in product design.
Posted in Design Services by Jamie Hartford on July 8, 2013

 

 

YouTube VIDEO: Integrating Human Factors Engineering into Medical Devices

 

 

Notes:

 

 Regulatory Considerations

  • Unlike other medication dosage forms, combination products require user interaction
  •  Combination products are unique in that their safety profile and product efficacy depends on user interaction
Human Factors Review: FDA Outlines Highest Priority Devices

Posted 02 February 2016By Zachary Brennan on http://www.raps.org/Regulatory-Focus/News/2016/02/02/24233/Human-Factors-Review-FDA-Outlines-Highest-Priority-Devices/ 

The US Food and Drug Administration (FDA) on Tuesday released new draft guidance to inform medical device manufacturers which device types should have human factors data included in premarket submissions, as well final guidance from 2011 on applying human factors and usability engineering to medical devices.

FDA said it believes these device types have “clear potential for serious harm resulting from use error and that review of human factors data in premarket submissions will help FDA evaluate the safety and effectiveness and substantial equivalence of these devices.”

Manufacturers should provide FDA with a report that summarizes the human factors or usability engineering processes they have followed, including any preliminary analyses and evaluations and human factors validation testing, results and conclusions, FDA says.

The list was based on knowledge obtained through Medical Device Reporting (MDRs) and recall data, and includes:

  • Ablation generators (associated with ablation systems, e.g., LPB, OAD, OAE, OCM, OCL)
  • Anesthesia machines (e.g., BSZ)
  • Artificial pancreas systems (e.g., OZO, OZP, OZQ)
  • Auto injectors (when CDRH is lead Center; e.g., KZE, KZH, NSC )
  • Automated external defibrillators
  • Duodenoscopes (on the reprocessing; e.g., FDT) with elevator channels
  • Gastroenterology-urology endoscopic ultrasound systems (on the reprocessing; e.g., ODG) with elevator channels
  • Hemodialysis and peritoneal dialysis systems (e.g., FKP, FKT, FKX, KDI, KPF ODX, ONW)
  • Implanted infusion pumps (e.g., LKK, MDY)
  • Infusion pumps (e.g., FRN, LZH, MEA, MRZ )
  • Insulin delivery systems (e.g., LZG, OPP)
  • Negative-pressure wound therapy (e.g., OKO, OMP) intended for home use
  • Robotic catheter manipulation systems (e.g., DXX)
  • Robotic surgery devices (e.g., NAY)
  • Ventilators (e.g., CBK, NOU, ONZ)
  • Ventricular assist devices (e.g., DSQ, PCK)

Final Guidance

In addition to the draft list, FDA finalized guidance from 2011 on applying human factors and usability engineering to medical devices.

The agency said it received over 600 comments on the draft guidance, which deals mostly with design and user interface, “which were generally supportive of the draft guidance document, but requested clarification in a number of areas. The most frequent types of comments requested revisions to the language or structure of the document, or clarification on risk mitigation and human factors testing methods, user populations for testing, training of test participants, determining the appropriate sample size in human factors testing, reporting of testing results in premarket submissions, and collecting human factors data as part of a clinical study.”

In response to these comments, FDA said it revised the guidance, which supersedes guidance from 2000 entitled “Medical Device Use-Safety: Incorporating Human Factors Engineering into Risk Management,” to clarify “the points identified and restructured the information for better readability and comprehension.”

Details

The goal of the guidance, according to FDA, is to ensure that the device user interface has been designed such that use errors that occur during use of the device that could cause harm or degrade medical treatment are either eliminated or reduced to the extent possible.

FDA said the most effective strategies to employ during device design to reduce or eliminate use-related hazards involve modifications to the device user interface, which should be logical and intuitive.

In its conclusion, FDA also outlined the ways that device manufacturers were able to save money through the use of human factors engineering (HFE) and usability engineering (UE).

– See more at: http://www.raps.org/Regulatory-Focus/News/2016/02/02/24233/Human-Factors-Review-FDA-Outlines-Highest-Priority-Devices/#sthash.cDTr9INl.dpuf

 

Please see an FDA PowerPoint on Human Factors Regulatory Issues for Combination Drug/Device Products here: MFStory_RAPS 2011 – HF of ComboProds_v4

 

 

 

 

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From GEN News Highlights

Reposted from GEN News

Nov 18, 2015
2.2.8

2.2.8   RNA-Based Drugs Turn CRISPR/Cas9 On and Off, Volume 2 (Volume Two: Latest in Genomics Methodologies for Therapeutics: Gene Editing, NGS and BioInformatics, Simulations and the Genome Ontology), Part 2: CRISPR for Gene Editing and DNA Repair

RNA-Based Drugs Turn CRISPR/Cas9 On and Off

  • This image depicts a conventional CRISPR-Cas9 system. The Cas9 enzyme acts like a wrench, and specific RNA guides act as different socket heads. Conventional CRISPR-Cas9 systems act continuously, raising the risk of off-target effects. But CRISPR-Cas9 systems that incorporate specially engineered RNAs could act transiently, potentially reducing unwanted changes. [Ernesto del Aguila III, NHGRI]

    By removing parts of the CRISPR/Cas9 gene-editing system, and replacing them with specially engineered molecules, researchers at the University of California, San Diego (UCSD) and Isis Pharmaceutical hope to limit the CRISPR/Cas9 system’s propensity for off-target effects. The researchers say that CRISPR/Cas9 needn’t remain continuously active. Instead, it could be transiently activated and deactivated. Such on/off control could prevent residual gene-editing activity that might go awry. Also, such control could be exploited for therapeutic purposes.

    The key, report the scientists, is the introduction of RNA-based drugs that can replace the guide RNA that usually serves to guide the Cas9 enzyme to a particular DNA sequence. When Cas9 is guided by a synthetic RNA-based drug, its cutting action can be suspended whenever the RNA-based drug is cleared. The Cas9’s cutting action can be stopped even more quickly if a second, chemically modified RNA drug is added, provided that it is engineered to direct inactivation of the gene encoding the Cas9 enzyme.

    Details about temporarily activated CRISPR/Cas9 systems appeared November 16 in the Proceedings of the National Academy of Sciences, in a paper entitled, “Synthetic CRISPR RNA-Cas9–guided genome editing in human cells.” The paper’s senior author, the USCD’s Don Cleveland, Ph.D., noted that the RNA-based drugs described in the study “provide many advantages over the current CRISPR/Cas9 system,” such as increased editing efficiency and potential selectivity.

    “Here we develop a chemically modified, 29-nucleotide synthetic CRISPR RNA (scrRNA), which in combination with unmodified transactivating crRNA (tracrRNA) is shown to functionally replace the natural guide RNA in the CRISPR-Cas9 nuclease system and to mediate efficient genome editing in human cells,” wrote the authors of the PNAS paper. “Incorporation of rational chemical modifications known to protect against nuclease digestion and stabilize RNA–RNA interactions in the tracrRNA hybridization region of CRISPR RNA (crRNA) yields a scrRNA with enhanced activity compared with the unmodified crRNA and comparable gene disruption activity to the previously published single guide RNA.”

    Not only did the synthetic RNA functionally replace the natural crRNA, it produced enhanced cleavage activity at a target DNA site with apparently reduced off-target cleavage. These findings, Dr. Cleveland explained, could provide a platform for multiple therapeutic applications, especially for nervous system diseases, using successive application of cell-permeable, synthetic CRISPR RNAs to activate and then silence Cas9 activity. “In addition,” he said, “[these designer RNAs] can be synthesized efficiently, on an industrial scale and in a commercially feasible manner today.”

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New Scaffold-Free 3D Bioprinting Method Available to Researchers

Reporter: Irina Robu, PhD

 

UPDATED ON 2/6/2016

Kenzan

SOURCE

Bio 3D Printer Regenova with Kenzan method

http://https://www.3dprintingbusiness.directory/news/kenzan-method-3d-bioprinting-cyfuses-regenova-system/

SOURCE

Cyfuse and Cyberdyne Are Pushing the Boundaries of 3D Printed Human Engineering With Regenova

by TE Halterman | Mar 3, 2015 | 3D Printers3D PrintingHealth 3D Printing |

http://3dprint.com/48312/cyfuse-and-cyberdyne-3d-printed-human-engineering/

 

Scafold-free

SOURCE

PUBLIC RELEASE: 3-FEB-2016

New scaffold-free 3-D bioprinting method available for first time in North America

Cell Applications primary cells and Regenova 3D Bio Printer from Cyfuse Biomedical combine to print robust 3-D tissue without introduction of extraneous scaffolding material

 

VIEW VIDEO

Regenova, Bio 3D Printer by Cyfuse

 

Cyfuse Biomedical K.K. and Cell Applications.Inc. publicized on February 3, 2016 that advanced tissue engineering services using 3D bioprinting approach will be available in North America. The services involved using Cyfuse Biomedica’s Regenova 3D Bio Printer, a state of the art robotic system that produces 3D tissues from cell and Cell Applications has created a pay by service bio-printing model that produces scaffold-free tissue available immediately to scientists in the U.S. and Canada for research use.

According to James Yu, Founder and CEO of Cell Applications having the Regenova 3D Bio Printer at our San Diego headquarters offers researchers an end-to-end, customized solution for creating scaffold-free, 3D-engineered tissues that diminish costs by reducing the lengthy processes typical in pharmaceutical drug discovery. In addition , Koji Kuchiishi, CEO of Cyfuse Biomedical having the Regenova 3D Bio Printer, combined with Cell Applications’ comprehensive, high-quality primary cell bank, offers researchers streamlined access to a nearly limitless selection of three dimensional tissues including those mimicking blood vessels, human neural tissue and liver constructs.

Unlike the other bioprinters on the market the bio-printer made by Regenova does not depend on scaffolding made of biomaterials such as collage or hydrogel to construct 3D tissue, the instrument assembles three dimensional microscopic tissue by forming spheroids, one at the time and lancing them on a fine needle array. The spheroids are guided by pre-programmed software which can be design and constructed into rods, spheres, tubes, sheets and other tissue configurations. In order for the engineered tissue to mature a bioreactor chamber is used. As the cells mature, they self-organize promoting strong, reliable tissue that can be further optimized by design of bio printer’s needle array that allows for optimum circulation of culture medium.

Source
http://www.cyfusebio.com/en/

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Third Annual BioPrinting and 3D Printing in the Life Sciences, 21-22 July 2016 at Academia, Singapore General Hospital Campus

Reporter: Aviva Lev-Ari, PhD, RN

 

Overview

Select Biosciences South East Asia are pleased to present Bioprinting and 3D Printing in the Life Sciences, taking place on the 21-22 July 2016 at Academia, the state-of-the-art conference facilities housed within the Singapore General Hospital Campus.

Building on the success of the 2013 and 2014 meetings The International Bioprinting Congress, we have decided to increase the scope of the event for 2016 to include the latest advances within 3D Printing for the Life Science arena.

We are honoured to again be working in partnership with our Conference Chairman, Professor Chua Chee Kai, Executive Director, Singapore Centre for 3D Printing (SC3DP), School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore.

We welcome Professor Martin Birchall, from University College London and Assistant Professor Wai Yee Yeong, from Nanyang Technological University as our Keynote Speakers for 2016.

The meeting will include scientific presentations from the leading international experts covering the latest advances developments and techniques within these allied fields, two highly topical panel discussions which will also highlight the views of the international regulatory authorities plus a tour of the facilities at the Centre for 3D Printing, hosted by Professor Chua.

We will provide you with a balanced overview of the industry from the varied perspectives of the leading researchers, solution providers and legislative authorities.

Attending this meeting will give you an excellent opportunity for networking and help you to build long term collaborations within this rapidly developing field.

We hope you can join us.

 

AGENDA

https://selectbiosciences.com/conferences/index.aspx?conf=BIO3D

@NTUsg

@SelectBio

Join the Third Annual Bioprinting and 3D Printing in the Life Sciences, taking place on the 21-22 July 2016 at Academia, Singapore General Hospital Campus.

Working in partnership with our Conference Chairman, Professor Chua Chee Kai, Executive Director, Singapore Centre for 3D Printing (SC3DP), Nanyang Technological University, Singapore.

We welcome Professor Martin Birchall, from University College London, Assistant Professor Wai Yee Yeong, Programme Director, SC3DP, Nanyang Technological University and Associate Professor Roger Narayan, University of North Carolina at Chapel Hill, as our Keynote Speakers for 2016.

The meeting will include scientific presentations from the following international experts who have already confirmed their participation.

Paulo Jorge Bártolo,

Chair of Advanced Manufacturing Processes & Director of the Manchester Biomanufacturing Centre, University of Manchester

Goh Bee Tin,

Senior Consultant, Department of Oral and Maxillofacial Surgery (OMS), Research Director and Deputy Director, Research and Education , National Dental Centre Singapore

Jerry Fuh,

Professor, National University of Singapore

Michael Golway,

President & CEO, Advanced Solutions, Inc.

Nazia Mehrban,

Post-Doctoral Researcher, University College London

L.P. Tan,

Associate Professor, School of Materials Science and Engineering, Nanyang Technological University

William G Whitford,

Senior Manager, GE Healthcare

Shoufeng Yang,

Associate Professor, University of Southampton

We are still accepting abstract submissions, if you would like to be considered for an oral presentation at this meeting, Submit an abstract for review now!

Oral Presentation Submission Deadline: 31 March 2016

We will address the following subject areas;

3D-Printing Applications in the Life Sciences

4D Bioprinting

Additive Manufacturing Technologies and Substrates

Bio-Ink and Bioprintable Hydrogels

Biofabrication and 3D-Bioprinting Technologies and Tools

Blueprints (Digital Models of Organs in STL Files)

Emerging Trends in Bioprinting

Intellectual Property and Patent Landscape in the Bioprinting Field

Laser Printing

Medical and Non-Medical Applications of Bioprinted Products

New Bioprinters

Organ Printing

Scaffolds and Biomaterials for Tissue Engineering

Technology Platforms for 3D-Printing

The application of Additive Manufacturing and Medical Devices

We hope you can join us for this exciting event, for further details please do not hesitate to contact me.

Best Regards

Linda

Linda Eriksson

Conference Manager

Select Biosciences South East Asia Pte. Ltd.

16 Raffles Quay, #33-03 Hong Leong Building,

Singapore 048581

l.eriksson@selectbio.com

www.SelectBio.com

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Lifelong Contraceptive Device for Men: Mechanical Switch to Control Fertility on Wish

Reporter and Curator: Dr. Sudipta Saha, Ph.D.

There aren’t many options for long-term birth control for men. The most common kinds of male contraception include

  • condoms,
  • withdrawal / pulling out,
  • outercourse, and
  • vasectomy.

But, other than vasectomy none of the processes are fully secured, comfortable and user friendly. Another solution may be

  • RISUG (Reversible Inhibition of Sperm Under Guidance, or Vasalgel)

which is said to last for ten years and no birth control pill for men is available till date.

VIEW VIDEO

http://www.mdtmag.com/blog/2016/01/implanted-sperm-switch-turns-mens-fertility-and?et_cid=5050638&et_rid=461755519&type=cta

Recently a German inventor, Clemens Bimek, developed a novel, reversible, hormone free, uncomplicated and lifelong contraceptive device for controlling male fertility. His invention is named as Bimek SLV, which is basically a valve that stops the flow of sperm through the vas deferens with the literal flip of a mechanical switch inside the scortum, rendering its user temporarily sterile. Toggled through the skin of the scrotum, the device stays closed for three months to prevent accidental switching. Moreover, the switch can’t open on its own. The tiny valves are less than an inch long and weigh is less than a tenth of an ounce. They are surgically implanted on the vas deferens, the ducts which carry sperm from the testicles, through a simple half-hour operation.

The valves are made of PEEK OPTIMA, a medical-grade polymer that has long been employed as a material for implants. The device is patented back in 2000 and is scheduled to undergo clinical trials at the beginning of this year. The inventor claims that Bimek SLV’s efficacy is similar to that of vasectomy, it does not impact the ability to gain and maintain an erection and ejaculation will be normal devoid of the sperm cells. The valve’s design enables sperm to exit the side of the vas deferens when it’s closed without any semen blockage. Leaked sperm cells will be broken down by the immune system. The switch to stop sperm flow can be kept working for three months or 30 ejaculations. After switching on the sperm flow the inventor suggested consulting urologist to ensure that all the blocked sperms are cleared off the device. The recovery time after switching on the sperm flow is only one day, according to Bimek SLV. However, men are encouraged to wait one week before resuming sexual activities.

Before the patented technology can be brought to market, it must undergo a rigorous series of clinical trials. Bimek and his business partners are currently looking for men interested in testing the device. If the clinical trials are successful then this will be the first invention of its kind that gives men the ability to control their fertility and obviously this method will be preferred over vasectomy.

 

References:

 

https://www.bimek.com/this-is-how-the-bimek-slv-works/

 

http://www.mdtmag.com/blog/2016/01/implanted-sperm-switch-turns-mens-fertility-and?et_cid=5050638&et_rid=461755519&type=cta

 

http://www.telegraph.co.uk/news/worldnews/europe/germany/12083673/German-carpenter-invents-on-off-contraception-switch-for-sperm.html

 

http://www.discovery.com/dscovrd/tech/you-can-now-turn-off-your-sperm-flow-with-the-flip-of-a-switch/

 

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3D “Squeeze” Helps Adult Cells Become Stem Cells

Reporter: Irina Robu, PhD

Scientists based at Ecole Polytechnique Fédérale de Lausanne led by Matthias Lutolf have been engineering 3D extracellular matrices—gels. These scientists report that they have developed a gel that boosts the ability of normal cells to revert into stem cells by simply “squeezing” them.

The detail of the scientists’ work appeared in Nature Materials, January 11, 2015 in an article entitled, “Defined three-dimensional microenvironments boost induction of pluripotency.” According to the authors they find that the physical cell confinement imposed by the 3D microenvironment boosts reprogramming through an accelerated mesenchymal-to-epithelial transition and increased epigenetic remodeling. They concluded that 3D microenvironmental signals act synergistically with reprogramming transcription factors to increase somatic plasticity.

The researchers discovered that they could reprogram the cells faster and more efficiently  by simply adjusting the composition, hence the stiffness and density of the surrounding gel. As a result, the gel exerts different forces on the cells, “squeezing” them.

The scientists propose that the 3D environment is key to this process, generating mechanical signals that work together with genetic factors to make the cell easier to transform into a stem cell. The technique can be applied to a large number of cells to produce stem cells on an industrial scale.

Source

http://www.genengnews.com/gen-news-highlights/3d-squeeze-helps-adult-cells-become-stem-cells/81252223/

 

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Platform Technologies for Directly Reconstructing 3D Living Biomaterials

Reporter: Irina Robu, PhD

The techniques of electrospraying and electrospinning have existed for at least a century. These techniques employs a high voltage applied to a needle accommodating the flow of media, placed above a counter electrode which could either be grounded or have an opposite charge to the needle—thus introducing the charged media to an electric field.

These endeavors have demonstrated the wider applicability of these technologies and hence in the last 20 years or so have been used for the direct handling of a wide range of materials, including bio-inspired materials. These investigations have generated interest in areas such as the development of fine monolayered surfaces, fabrication of scaffolds which could be used for many laboratory-based fundamental biological studies.

In 2005, Jayasinghe et al. began investigations into both electrospraying and electrospinning of immortalized cell lines. Even though the high voltages involved, these cells were  found to be viable post-electrospraying/electrospinning. Additional work has extended these studies to different cell types, both murine and human, immortalized or primary, stem cells, and even whole fertilized embryos from model organisms. Established protocols (such as flow cytometry, genetic/genomic interrogation, and microarray analysis) proved that cells processed using either electrospraying or electrospinning were indistinguishable from controls. Hence bio-electrospraying (BES) and cell electrospinning (CE) have become platform technologies for the biological and life science and are the leading technologies for the direct handling of cells—both for distribution of cells with pinpoint precision as cell-bearing droplets, and for the formation of truly 3D living scaffolds.

Previous studies have been carried out with processed cells suspended in matrices generated from animal/tumor-derived materials which contain largely uncharacterized growth factors and bioactive signals. This makes them very undesirable for clinical assays. While not applicable to humans, they can be used  with advanced biopolymers, which could be directly translated to humans, and have the potential for creating artificial constructs which could be used for a variety of applications in the regenerative medicine field. The present study describes the in vivo application of such biopolymers, using murine macrophages to interrogate biocompatibility and cellular behavior post-transfer.

Source

http://onlinelibrary.wiley.com/doi/10.1002/adma.201503001/full

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Research on Scaffolds to support Stem Cells prior to Implantation

Reporter: Aviva Lev-Ari, PhD, RN

 

 

Fibrous Scaffolds with Varied Fiber Chemistry and Growth Factor Delivery Promote Repair in a Porcine Cartilage Defect Model

Iris L. Kim, Christian G. Pfeifer, Matthew B. Fisher, Vishal Saxena, Gregory R. Meloni, Mi Y. Kwon, Minwook Kim, David R. Steinberg, Robert L. Mauck, Jason A. Burdick

Tissue Engineering Part A. November 2015: 2680-2690.

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  Hydrogel Microencapsulated Insulin-Secreting Cells Increase Keratinocyte Migration, Epidermal Thickness, Collagen Fiber Density, and Wound Closure in a Diabetic Mouse Model of Wound Healing

Ayesha Aijaz, Renea Faulknor, François Berthiaume, Ronke M. Olabisi

Tissue Engineering Part A. November 2015: 2723-2732.

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Bone Regeneration Using Hydroxyapatite Sponge Scaffolds with In Vivo Deposited Extracellular Matrix

Reiza Dolendo Ventura, Andrew Reyes Padalhin, Young-Ki Min, Byong-Taek Lee

Tissue Engineering Part A. November 2015: 2649-2661.

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In Vivo Evaluation of Adipose-Derived Stromal Cells Delivered with a Nanofiber Scaffold for Tendon-to-Bone Repair

Justin Lipner, Hua Shen, Leonardo Cavinatto, Wenying Liu, Necat Havlioglu, Younan Xia, Leesa M. Galatz,Stavros Thomopoulos

Tissue Engineering Part A. November 2015: 2766-2774.

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The Effects of Platelet-Rich Plasma on Cell Proliferation and Adipogenic Potential of Adipose-Derived Stem Cells

Han Tsung Liao, Isaac B. James, Kacey G. Marra, J. Peter Rubin

Tissue Engineering Part A. November 2015: 2714-2722.

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Ligament Tissue Engineering Using a Novel Porous Polycaprolactone Fumarate Scaffold and Adipose Tissue-Derived Mesenchymal Stem Cells Grown in Platelet Lysate

Eric R. Wagner, Dalibel Bravo, Mahrokh Dadsetan, Scott M. Riester, Steven Chase, Jennifer J. Westendorf,Allan B. Dietz, Andre J. van Wijnen, Michael J. Yaszemski, Sanjeev Kakar

Tissue Engineering Part A. November 2015: 2703-2713.

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Contribution to Inflammatory Bowel Disease (IBD) of bacterial overgrowth in gut on a chip

Larry H. Bernstein, MD, FCAP, Curator

LPBI

 

Contributions of microbiome and mechanical deformation to intestinal bacterial overgrowth and inflammation in a 

human gut-on-a-chip 
Gut-On-a-Chip Holds Clues for Treating Inflammatory Bowel Diseases
Greg Watry
Human intestinal epithelial cells cultured in the Wyss Institute's human gut-on-a-chip form differentiated intestinal villi when cultured in the presence of lifelike fluid flow and rhythmic, peristalsis-like motions. Here the villi are visible using a traditional microscope (left) or a confocal microscope (right); when the same villi are stained with fluorescent antibodies, it clearly reveals the nuclei in the intestinal cells (blue) and their specialized apical membranes when they contact the intestinal lumen (green). Credit: Wyss Institute at Harvard University
Human intestinal epithelial cells cultured in the Wyss Institute’s human gut-on-a-chip form differentiated intestinal villi when cultured in the presence of lifelike fluid flow and rhythmic, peristalsis-like motions. Here the villi are visible using a traditional microscope (left) or a confocal microscope (right); when the same villi are stained with fluorescent antibodies, it clearly reveals the nuclei in the intestinal cells (blue) and their specialized apical membranes when they contact the intestinal lumen (green). Credit: Wyss Institute at Harvard University

Roughly the size of a computer memory stick and made of clear flexible polymer, the human gut-on-a-chip was created by Harvard Univ.’s Wyss Institute in 2012. Three years later, researchers are utilizing the technology in hopes of creating new therapies for inflammatory bowel diseases (IBD).

The Centers for Disease Control and Prevention estimates that between 1 and 1.3 million people suffer from IBD, including such diseases as ulcerative colitis and Crohn’s disease. With origins still mysterious, IBD is currently incurable.

“It has not been possible to study…human intestinal inflammatory diseases, because it is not possible to independently control these parameters in animal studies or in vitro models,” wrote the researchers in Proceedings of the National Academy of the Sciences. “In particular, given the recent recognition of the central role of the intestinal microbiome in human health and disease, including intestinal disorders, it is critical to incorporate commensal microbes into experimental models, however, this has not been possible using conventional culture systems.”

Additionally, static in vitro methods fail to replicate the pathophysiology of human IBD.

But the hollow-channeled microfluidic gut-on-a-chip successfully simulates the human intestine’s physical structure, microenvironment, peristalsis-like motion, and fluid flow.

“With our human gut-on-a-chip, we can not only culture the normal gut microbiome for extended times, but we can also analyze contributions of pathogens, immune cells, and vascular and lymphatic endothelium, as well as model specific diseases to understand the complex pathophysiological responses of the intestinal tract,” said Donald Ingber, founding director of the Wyss Institute.

The device was “used to co-culture multiple commensal microbes in contact with living human intestinal epithelial cells for more than a week in vitro and to analyze how gut microbiome, inflammatory cells, and peristalsis-associated mechanical deformations independently contribute to intestinal bacterial overgrowth and inflammation,” the researchers wrote.

Thus far, use of the device has yielded two interesting observations.

Four proteins—called cytokines—work together to trigger an inflammatory responses that exacerbate the bowel, the researchers found. Potentially, this new discovery could lead to the development of treatments that block the cytokine interaction.

Another observation, the researchers noted, is that “by ceasing peristalsis-like motions while maintaining luminal flow, lack of epithelial deformation was shown to trigger bacterial overgrowth similar to that observed in patients with ileus and inflammatory bowel disease,” according to the researchers.

The researchers believe the micro-device may one day be applicable to precision medicine. Eventually, a custom treatment may arise from scientists using a patient’s gut microbiota and cells on a human gut-on-a-chip.

 

 

Contributions of microbiome and mechanical deformation to intestinal bacterial overgrowth and inflammation in a human gut-on-a-chip
Hyun Jung Kima,1, Hu Lia,2, James J. Collinsa,b,c,d,e,f,3, and Donald E. Ingbera,g,h,
http://www.pnas.org/content/early/2015/12/09/1522193112.full.pdf

A human gut-on-a-chip microdevice was used to coculture multiple commensal microbes in contact with living human intestinal epithelial cells for more than a week in vitro and to analyze how gut microbiome, inflammatory cells, and peristalsis-associated mechanical deformations independently contribute to intestinal bacterial overgrowth and inflammation. This in vitro model replicated results from past animal and human studies, including demonstration that probiotic and antibiotic therapies can suppress villus injury induced by pathogenic bacteria. By ceasing peristalsis-like motions while maintaining luminal flow, lack of epithelial deformation was shown to trigger bacterial overgrowth similar to that observed in patients with ileus and inflammatory bowel disease. Analysis of intestinal inflammation on-chip revealed that immune cells and lipopolysaccharide endotoxin together stimulate epithelial cells to produce four proinflammatory cytokines (IL-8, IL-6, IL-1β, and TNF-α) that are necessary and sufficient to induce villus injury and compromise intestinal barrier function. Thus, this human gut-on-a-chip can be used to analyze contributions of microbiome to intestinal pathophysiology and dissect disease mechanisms in a controlled manner that is not possible using existing in vitro systems or animal models.

 

Significance The main advance of this study is the development of a microengineered model of human intestinal inflammation and bacterial overgrowth that permits analysis of individual contributors to the pathophysiology of intestinal diseases, such as ileus and inflammatory bowel disease, over a period of weeks in vitro. By studying living human intestinal epithelium, with or without vascular and lymphatic endothelium, immune cells, and mechanical deformation, as well as living microbiome and pathogenic microbes, we identified previously unknown contributions of specific cytokines, mechanical motions, and microbiome to intestinal inflammation, bacterial overgrowth, and control of barrier function. We provide proof-of-principle to show that the microfluidic gut-on-a-chip device can be used to create human intestinal disease models and gain new insights into gut pathophysiology.

 

Various types of inflammatory bowel disease (IBD), such as Crohn’s disease and ulcerative colitis, involve chronic inflammation of human intestine with mucosal injury and villus destruction (1), which is believed to be caused by complex interactions between gut microbiome (including commensal and pathogenic microbes) (2), intestinal mucosa, and immune components (3). Suppression of peristalsis also has been strongly associated with intestinal pathology, inflammation (4, 5), and small intestinal bacterial overgrowth (5, 6) in patients with Crohn’s disease (7) and ileus (8). However, it has not been possible to study the relative contributions of these different potential contributing factors to human intestinal inflammatory diseases, because it is not possible to independently control these parameters in animal studies or in vitro models. In particular, given the recent recognition of the central role of the intestinal microbiome in human health and disease, including intestinal disorders (2), it is critical to incorporate commensal microbes into experimental models; however, this has not been possible using conventional culture systems. Most models of human intestinal inflammatory diseases rely either on culturing an intestinal epithelial cell monolayer in static Transwell culture (9) or maintaining intact explanted human intestinal mucosa ex vivo (10) and then adding live microbes and immune cells to the apical (luminal) or basolateral (mucosal) sides of the cultures, respectively. These static in vitro methods, however, do not effectively recapitulate the pathophysiology of human IBD. For example, intestinal epithelial cells cultured in Transwell plates completely fail to undergo villus differentiation, produce mucus, or form the various specialized cell types of normal intestine. Although higher levels of intestinal differentiation can be obtained using recently developed 3D organoid cultures (11), it is not possible to expose these cells to physiological peristalsis-like motions or living microbiome in long-term culture, because bacterial overgrowth occurs rapidly (within ∼1 d) compromising the epithelium (12). This is a major limitation because establishment of stable symbiosis between the epithelium and resident gut microbiome as observed in the normal intestine is crucial for studying inflammatory disease initiation and progression (13), and rhythmical mechanical deformations driven by peristalsis are required to both maintain normal epithelial differentiation (14) and restrain microbial overgrowth in the intestine in vivo (15).

Thus, we set out to develop an experimental model that would overcome these limitations. To do this, we adapted a recently described human gut-on-a-chip microfluidic device that enables human intestinal epithelial cells (Caco-2) to be cultured in the presence of physiologically relevant luminal flow and peristalsislike mechanical deformations, which promotes formation of intestinal villi lined by all four epithelial cell lineages of the small intestine (absorptive, goblet, enteroendocrine, and Paneth) (12, 16). These villi also have enhanced barrier function, drug-metabolizing cytochrome P450 activity, and apical mucus secretion compared with the same cells grown in conventional Transwell cultures, which made it possible to coculture a probiotic gut microbe (Lactobacillus rhamnosus GG) in direct contact with the intestinal epithelium for more than 2 wk (12), in contrast to static Transwell cultures (17) or organoid cultures (11) that lose viability within hours under similar conditions. In the present study, we leveraged this human gut-on-a-chip to develop a disease model of small intestinal bacterial overgrowth (SIBO) and inflammation. We analyzed how probiotic and pathogenic bacteria, lipopolysaccharide (LPS), immune cells, inflammatory cytokines, vascular endothelial cells and mechanical forces contribute individually, and in combination, to intestinal inflammation, villus injury, and compromise of epithelial barrier function. We also explored whether we could replicate the protective effects of clinical probiotic and antibiotic therapies on-chip to demonstrate its potential use as an in vitro tool for drug development, as well as for dissecting fundamental disease mechanisms.

 

Fig. 1. The human gut-on-a-chip microfluidic device and changes in phenotype resulting from different culture conditions on-chip, as measured using genome-wide gene profiling. (A) A photograph of the device. Blue and red dyes fill the upper and lower microchannels, respectively. (B) A schematic of a 3D cross-section of the device showing how repeated suction to side channels (gray arrows) exerts peristalsis-like cyclic mechanical strain and fluid flow (white arrows) generates a shear stress in the perpendicular direction. (C) A DIC micrograph showing intestinal basal crypt (red arrow) and villi (white arrow) formed by human Caco-2 intestinal epithelial cells grown for ∼100 h in the gut-on-achip under medium flow (30 μL/h) and cyclic mechanical stretching (10%, 0.15 Hz). (Scale bar, 50 μm.) (D) A confocal immunofluorescence image showing a horizontal cross-section of intestinal villi similar to those shown in Fig. 1C, stained for F-actin (green) that labels the apical brush border of these polarized intestinal epithelial cells (nuclei in blue). (Scale bar, 50 μm.) (E) Hierarchical clustering analysis of genome-wide transcriptome profiles (Top) of Caco-2 cells cultured in the static Transwell, the gut-on-a-chip (with fluid flow at 30 μL/h and mechanical deformations at 10%, 0.15 Hz) (Gut Chip), or the mechanically active gut-on-a-chip cocultured with the VSL#3 formulation containing eight probiotic gut microbes (Gut Chip + VSL#3) for 72 h compared with normal human small intestinal tissues (Duodenum, Jejunum, and Ileum; microarray data from the published GEO database). The dendrogram was generated based on the averages calculated across all replicates, and all branches in the cluster have the approximately unbiased (AU) P value equal to 100. The y axis next to the dendrogram represents the metric for Euclidean distance between samples. Corresponding pseudocolored GEDI maps analyzing profiles of 650 metagenes between samples described above (Bottom).

 

Fig. 2. Reconstitution of pathological intestinal injury induced by interplay between nonpathogenic or pathogenic enteroinvasive E. coli bacteria or LPS endotoxin with immune cells. (A) DIC images showing that the normal villus morphology of the intestinal epithelium cultured on-chip (Control) is lost within 24 h after EIEC (serotype O124:NM) are added to the apical channel of the chip (+EIEC; red arrows indicate bacterial colonies). (B) Effects of GFP-EC, LPS (15 μg/mL), EIEC, or no addition (Control) on intestinal barrier function (Left). Right shows the TEER profiles in the presence of human PBMCs (+PBMC). GFP-EC, LPS, and EIEC were added to the apical channel (intestinal lumen) at 4, 12, and 35 h, respectively, and PBMCs were subsequently introduced through the lower capillary channel at 44 h after the onset of experiment (0 h) (n = 4). (C) Morphological analysis of intestinal villus damage in response to addition of GFP-EC, LPS, and EIEC in the absence (−PBMC) or the presence of immune components (+PBMC). Schematics (experimental setup), phase contrast images (horizontal view, taken at 57 h after onset), and fluorescence confocal micrographs (vertical cross-sectional views at 83 h after onset) were sequentially displayed. F-actin and nuclei were coded with magenta and blue, respectively. (D) Quantification of intestinal injury evaluated by measuring changes in lesion area (Top; n = 30) and the height of the villi (Bottom; n = 50) in the absence (white) or the presence (gray) of PBMCs. Intestinal villi were grown in the gut-on-a-chip under trickling flow (30 μL/h) with cyclic deformations (10%, 0.15 Hz) during the preculture period for ∼100 h before stimulation (0 h, onset). Asterisks indicate statistical significance compared with the control at the same time point (*P < 0.001, **P < 0.05). (Scale bars, 50 μm.)

 

Recapitulating Organ-Level Intestinal Inflammatory Responses. During inflammation in the intestine, pathophysiological recruitment of circulating immune cells is regulated via activation of the underlying vascular endothelium. To analyze this organ-level inflammatory response in our in vitro model, a monolayer of human microvascular endothelial cells (Fig. 3 C and D and Fig. S6 A and C) or lymphatic endothelial cells (Fig. S6 B and C) was cultured on the opposite (abluminal) side of the porous ECM-coated membrane in the lower microchannel of the device to effectively create a vascular channel (Fig. 3C). To induce intestinal inflammatory responses, LPS (Fig. 3 C and D) or TNF-α (Fig. S6) was flowed through the upper epithelial channel for 24 h, and then PBMCs were added to the vascular channel for 1 h without flow (Fig. 3 C and D). Treatment with both LPS (or TNF-α) and PBMCs resulted in the activation of intercellular adhesion molecule-1 (ICAM-1) expression on the surface of the endothelium (Fig. 3 C and D, Left, and Fig. S6) and a significant increase (P < 0.001) in the number of PBMCs that adhered to the surface of the capillary endothelium compared with controls (Fig. 3D). These results are consistent with our qPCR results, which also showed up-regulation of genes involved in immune cell trafficking (Fig. S5). Neither addition of LPS nor PBMCs alone was sufficient to induce ICAM-1 expression in these cells (Fig. 3D), which parallels the effects of LPS and PBMCs on epithelial production of inflammatory cytokines (Fig. 3A) as well as on villus injury (Fig. 2 B and D).

Evaluating Antiinflammatory Probiotic and Antibiotic Therapeutics On-Chip. To investigate how the gut microbiome modulates these inflammatory reactions, we cocultured the human intestinal villi with the eight strains of probiotic bacteria in the VSL#3 formulation that significantly enhanced intestinal differentiation (Fig. 1E and Fig. S1B). To mimic the in vivo situation, we colonized our microengineered gut on a chip with the commensal microbes (VSL#3) first and then subsequently added immune cells (PBMCs), pathogenic bacteria (EIEC), or both in combination. The VSL#3 microbial cells inoculated into the germ-free lumen of the epithelial channel primarily grew as discrete microcolonies in the spaces between adjacent villi (Fig. 4A and Movie S3) for more than a week in culture (Fig. S7A), and no planktonic growth was detected. These microbes did not overgrow like the EIEC (Fig. 2A and Movie S2), although occasional microcolonies also appeared at different spatial locations in association with the tips of the villi (Fig. S7 B and C). The presence of these living components of the normal gut microbiome significantly enhanced (P < 0.001) intestinal barrier function, producing more than a 50% increase in TEER relative to control cultures (Fig. 4B) without altering villus morphology (Fig. 4C). This result is consistent with clinical studies suggesting that probiotics, including VSL#3, can significantly enhance intestinal barrier function in vivo (18).

To mimic the effects of antibiotic therapies that are sometimes used clinically in patients with intestinal inflammatory disease (29), we identified a dose and combination of antibiotics (100 units per mL penicillin and 100 μg/mL streptomycin) that produced effective killing of both EIEC and VSL#3 microbes in liquid cultures (Fig. S9) and then injected this drug mixture into the epithelial channel of guton-a-chip devices infected with EIEC. When we added PBMCs to these devices 1 h later, intestinal barrier function (Fig. 4B) and villus morphology (Fig. 4C) were largely protected from injury, and there was a significant reduction in lesion area (Fig. 4D). Thus, the gut-on-a-chip was able to mimic suppression of injury responses previously observed clinically using other antibiotics that produce similar bactericidal effects.

Analyzing Mechanical Contributions to Bacterial Overgrowth. Finally, we used the gut-on-a-chip to analyze whether physical changes in peristalsis or villus motility contribute to intestinal pathologies, such as the small intestinal bacterial overgrowth (SIBO) (5, 6) observed in patients with ileus (8) and IBD (7). When the GFPEC bacteria were cultured on the villus epithelium under normal flow (30 μL/h), but in the absence of the physiological cyclic mechanical deformations, the number of colonized bacteria was significantly higher (P < 0.001) compared with gut chips that experienced mechanical deformations (Fig. 5A). Bacterial cell densities more than doubled within 21 h when cultured under conditions without cyclic stretching compared with gut chips that experienced physiological peristalsis-like mechanical motions, even though luminal flow was maintained constant (Fig. 5B). Thus, cessation of epithelial distortion appears to be sufficient to trigger bacterial overgrowth, and motility-induced luminal fluid flow is not the causative factor as assumed previously (7).

 

Discussion One of the critical prerequisites for mimicking the living human intestine in vitro is to establish a stable ecosystem containing physiologically differentiated intestinal epithelium, gut bacteria, and immune cells that can be cultured for many days to weeks. Here we leveraged a mechanically active gut-on-a-chip microfluidic device to develop an in vitro model of human intestinal inflammation that permits stable long-term coculture of commensal microbes of the gut microbiome with intestinal epithelial cells. The synthetic model of the human living intestine we built recapitulated the minimal set of structures and functions necessary to mimic key features of human intestinal pathophysiology during chronic inflammation and bacterial overgrowth including epithelial and vascular inflammatory processes and destruction of intestinal villi.

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Surgical Separation of Conjoined Twins been Computer-Aided with CT and 3D BioPrinting

Reporter: Aviva Lev-Ari, PhD, RN

 

From: “PR Newswire for Journalists” <push_services@prnewswire.com>

Sent: Wednesday, December 02, 2015 4:04 PM

To: info@newmedinc.com

Subject: CT and 3-D Printing Aid Surgical Separation of Conjoined Twins

 

CT and 3-D Printing Aid Surgical Separation of Conjoined Twins

CHICAGO, Dec. 2, 2015 /PRNewswire-USNewswire/ — A combination of detailed CT imaging and 3-D printing technology has been used for the first time in the surgical planning for separation of conjoined twins, according to a study presented today at the annual meeting of the Radiological Society of North America (RSNA).

Conjoined twins, or twins whose bodies are connected, account for approximately one of every 200,000 live births. Survival rates are low and separating them through surgery is extremely difficult because they often share organs and blood vessels.

Specialists at Texas Children’s Hospital in Houston brought a new approach to these challenges when they set out to surgically separate Knatalye Hope and Adeline Faith Mata, conjoined twins from Lubbock, Texas. Knatalye and Adeline were born on April 11, 2014, connected from the chest all the way down to the pelvis.

“This case was unique in the extent of fusion,” said the study’s lead author, Rajesh Krishnamurthy, M.D., chief of radiology research and cardiac imaging at Texas Children’s Hospital. “It was one of the most complex separations ever for conjoined twins.”

To prepare for the separation surgery, Dr. Krishnamurthy and colleagues performed volumetric CT imaging with a 320-detector scanner, administering intravenous contrast separately to both twins to enhance views of vital structures and help plan how to separate them to ensure survival of both children. They used a technique known as target mode prospective EKG gating to freeze the motion of the hearts on the images and get a more detailed view of the cardiovascular anatomy, while keeping the radiation exposure low.

“The CT scans showed that the babies’ hearts were in the same cavity but were not fused,” Dr. Krishnamurthy said. “Also, we detected a plane of separation of the liver that the surgeons would be able to use.”

The team translated the CT imaging results into a color-coded physical 3-D model with skeletal structures and supports made in hard plastic resin, and organs built from a rubber-like material. The livers were printed as separate pieces of the transparent resin, with major blood vessels depicted in white for better visibility. The models were designed so that they could be assembled together or separated during the surgical planning process. The surgical team used the models during the exhaustive preparation process leading up to the surgery.

On February 17, a little more than 10 months after they were born, the Mata twins underwent surgical separation by a team of more than 26 clinicians, including 12 surgeons, six anesthesiologists and eight surgical nurses. The official separation took place approximately 18 hours into the 26-hour surgery.

The 3-D models proved to be an excellent source of information, as there were no major discrepancies between the models and the twins’ actual anatomy.

“The surgeons found the landmarks for the liver, hearts and pelvic organs just as we had described,” Dr. Krishnamurthy said. “The concordance was almost perfect.”

Dr. Krishnamurthy expects the combination of volumetric CT, 3-D modeling, and 3-D printing to become a standard part of preparation for surgical separation of conjoined twins, although barriers remain to its adoption.

“The 3-D printing technology has advanced quite a bit, and the costs are declining. What’s limiting it is a lack of reimbursement for these services,” he said. “The procedure is not currently recognized by insurance companies, so right now hospitals are supporting the costs.”

Besides assisting clinicians prepare for surgery, the 3-D model also served another important function: helping the twins’ parents, Elysse and John Eric Mata, understand the process.

“When I showed the mother the model and explained the procedure, she held my hand and thanked me,” Dr. Krishnamurthy recalled. “They said, ‘For the first time, we understand what is going to happen with our babies.'”

Knatalye Hope returned home in May 2015 and her sister Adeline Faith came home a month later. They are both doing well and have a Facebook page, “Helping Faith & Hope Mata,” with updates on their progress.

Co-authors on the study are Nicholas Dodd, B.S., Darrell Cass, M.D., Amrita Murali and Jayanthi Parthasarathy, B.D.S., M.S., Ph.D.

Note: Copies of RSNA 2015 news releases and electronic images will be available online at RSNA.org/press15 beginning Monday, Nov. 30.

RSNA is an association of more than 54,000 radiologists, radiation oncologists, medical physicists and related scientists, promoting excellence in patient care and health care delivery through education, research and technologic innovation. The Society is based in Oak Brook, Ill. (RSNA.org)

For patient-friendly information on CT, visit RadiologyInfo.org.

SOURCE Radiological Society of North America (RSNA)

Radiological Society of North America (RSNA)

CONTACT: RSNA Newsroom, 1-312-791-6610; Before 11/28/15 or after 12/3/15: RSNA Media Relations, 1-630-590-7762; Linda Brooks, 1-630-590-7738, lbrooks@rsna.org; Maureen Morley, 1-630-590-7754, mmorley@rsna.org

Web Site: http://www.rsna.org

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From: “Dr. Katie Katie Siafaca” <info@newmedinc.com>

Reply-To: “Dr. Katie Katie Siafaca” <info@newmedinc.com>

Date: Thursday, December 3, 2015 at 2:00 PM

To: Aviva Lev-Ari <AvivaLev-Ari@alum.berkeley.edu>

Subject: fw: CT and 3-D Printing Aid Surgical Separation of Conjoined Twins

 

 

 

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