Tissue Engineering

Tissue Engineering
วิศวกรรมเนื้อเยื่อ (Tissue Engineering) เป็นกระบวนการสร้างเนื้อเยื่อ (regeneration of functional tissues) เพื่อทดแทน ซ่อมแซม หรือปรับปรุงการทำงานของเนื้อเยื่อหรืออวัยวะที่สูญเสียหรือบาดเจ็บ ซึ่งโดยปกติจะไม่มีการงอกใหม่เองในมนุษย์ ได้แก่ ผิวหนังแท้ เส้นประสาท กระดูก กระดูกอ่อน กล้ามเนื้อหัวใจ เป็นต้น กระบวนการสร้างเนื้อเยื่อต้องใช้การพัฒนาความรู้ต่างๆสามด้านหลัก ได้แก่ วิศวกรรมของวัสดุ ชีววิทยาของเซลล์ และวิศวกรรมชีวเคมี โดยจะเริ่มจากการพัฒนาชีววัสดุ (วัสดุที่เข้ากับร่างกายได้ดี Biomaterials) เพื่อทำหน้าที่เป็นโครงเลี้ยงเซลล์ (scaffold) ซึ่งส่วนใหญ่นิยมใช้ชีววัสดุจากธรรมชาติ เช่น คอลลาเจน เจลาติน ไหมหรือวัสดุสังเคราะห์ขึ้น เช่น PLA PCL โครงเลี้ยงเซลล์จะถูกนำไปใช้เลี้ยงเซลล์ที่ถูกคัดแยก และขยายพันธุ์ให้มีปริมาณมากพอ แล้วการชักนำให้เปลี่ยนแปลง (differentiate) ไปเป็นเนื่อเยื่อที่ต้องการอย่างสมบูรณ์และสามารถทำงานได้ตามวัตถุประสงค์ ด้วยการควบคุมสภาวะแวดล้อมภายนอกในเครื่องปฏิกรณ์ชีวภาพ (Bioreactor) หรือในร่างกายสิ่งมีชีวิต (in vivo regeneration)
ปัจจุบันงานวิจัยในสาขานี้มีดังนี้
วิศวกรรมเนื้อเยื่อผิวหนัง วิศวกรรมเนื้อเยื่อเพื่อพัฒนากระดูกเทียมจากวัสดุชีวภาพในประเทศ วิศวกรรมเนื้อเยื่อกระดูกอ่อนจากเซลล์ต้นกำเนิด ระบบนำส่ง growth factor ในกระบวนการซ่อมสร้างเส้นประสาทส่วนปลาย การพัฒนาระบบนำส่งเมโทรเทรกเสสทางผิวหนังเพื่อรักษาโรคผิวหนังเรื้อนกวาง การพัฒนาระบบนำส่งสารสกัดจากสมุนไพรไทยที่ไม่ละลายน้ำ การสกัด ดัดแปลง และพัฒนาวัสดุทางการแพทย์จากชีววัสดุธรรมชาติ เช่น คอลลาเจน ไคโตซานแบคทีเรียเซลลูโลส สารสกัดจากสาหร่าย ไซโครเด็กตริน การพัฒนาเครื่องปฏิกรณ์ชีวภาพเพื่อการเพิ่มจำนวนเซลล์ต้นกำเนิด
From >http://cubme.eng.chula.ac.th/index.php?q=research/TissueEngineeringAndDrugDeliverySystem

CNN's Dr. Sunjay Gupta on da Vinci Surgery

Researchers laud robot-guided heart surgeryBy Debra GoldschmidtCNN Medical UnitTuesday, November 19, 2002
CHICAGO (CNN) -- Robotic heart surgery using the da Vinci Surgical System has many advantages for patients and doctors, according to research presented to cardiologists at the annual Scientific Sessions of the American Heart Association on Tuesday.
Surgeons from New York Presbyterian Hospital presented the outcomes of 17 patients after having a heart defect -- called atrial septal defect -- repaired using the robot for assistance.
Of the 17 patients, 16 of them had their hearts repaired in a totally robotic operation. One patient required additional repair five days after the first surgery. The average length of stay in the hospital after the surgery was three days compared with seven to 10 days for traditional surgery. None of the patients experienced major complications.
The robotic technique requires four puncture wounds, each an inch in diameter. Surgeons use pencil-sized instruments to operate on the heart. They sit several feet away from the patient at a console where they see inside the patient on a monitor.
Lead researcher, Dr. Michael Argenziano said the success rate "proved we can do this surgery in a closed chest approach." The alternative is the traditional technique of cracking the chest -- done by a long incision, cutting the bone, and then splitting the ribs.
"The main advantage is that these patients were able to recover quickly." he said.
Patients recovering from the traditional approach usually have several inactive weeks before they're able to resume regular activity, but patients who undergo robotic surgery only spend a couple of days recovering from local wounds. Argenziano was amazed when one of his patients was able to pick up her toddler the day after her surgery.
Compared with other minimally invasive heart surgery approaches, robotic assistance allows surgeons to have better control over the surgical instruments and a better view of what they are doing.
However, there are disadvantages -- time being one of them. Robotic-assisted surgery takes nearly double the amount of time that a typical open-heart surgery takes. That means a patient is under anesthesia longer and nurses and other staff must also work longer hours.
The cost seems to be a disadvantage as well. In the short term, hospitals pay millions of dollars for the robot and the disposable instruments needed.
But Argenziano argues that although the robotic-assisted surgeries cost about $2,000 more per operation, in the end the cost comes out about even because patients are out of the hospital sooner.
Money is saved after surgery on nursing care and pain medications, he said, in addition to the societal benefits from faster recovery.
The procedure is still experimental under a U.S. Food and Drug Administration clinical trial; therefore, the robot's manufacturer picks up any costs that exceed the normal cost of heart surgery.
Seven other patients have undergone the procedure at other centers as part of the trial.
Argenziano said they've had no trouble finding patients willing to try the experimental surgery because of the faster recovery time. He added that the surgeons can have the patient's chest open in one minute's time should they suddenly need to convert to traditional surgery -- something they haven't had to do.
In another trial, Argenziano and other surgeons are using the robot to perform closed-chest coronary bypass surgery.
Last week the FDA gave approval for the robot to be used for mitral valve repair surgery. This is the first robotic heart surgery to be granted clearance by the FDA.
The da Vinci Surgical System is made by California-based Intuitive Surgical Systems. There are 132 systems in hospitals worldwide and nearly 100 are in U.S. hospitals.
Source>http://archives.cnn.com/2002/HEALTH/11/19/heart.robots/index.html

Robotic-Assisted Prostate Surgery

The da Vinci? Surgical SystemLearn about the newest da Vinci Surgical System:
Read moreThe da Vinci Surgical System consists of an ergonomically designed surgeon’s console, a patient-side cart with four interactive robotic arms, the high-performance InSite? Vision System and proprietary EndoWrist? Instruments. Powered by state-of-the-art robotic technology, the surgeon’s hand movements are scaled, filtered and seamlessly translated into precise movements of the EndoWrist Instruments. The net result: an intuitive interface with breakthrough surgical capabilities.
Details>>http://www.intuitivesurgical.com/products/davinci_surgicalsystem/index.aspx

Da Vinci Surgical System

From Wikipedia, the free encyclopedia

Da Vinci Surgical System Manufacturer Intuitive Surgical Type Robotic surgery Units sold 1,032 units worldwide

The da Vinci Surgical System is a robotic surgical system made by Intuitive Surgical and designed to facilitate complex surgery using a minimally invasive approach. The system is controlled by a surgeon from a console. It is commonly used for prostatectomies and increasingly for cardiac valve repair and gynecologic surgical procedures.

Overview

The da Vinci System consists of a surgeon’s console that is typically in the same room as the patient and a patient-side cart with four interactive robotic arms controlled from the console. Three of the arms are for tools that hold objects, act as a scalpel, scissors, bovie, or unipolar or dipolar electrocautery instruments. The fourth arm is for an endoscopic camera with two lenses that gives the surgeon full stereoscopic vision from the console. The surgeon sits at the console and looks through two eye holes at a 3-D image of the procedure, meanwhile maneuvering the arms with two foot pedals and two hand controllers. The da Vinci System scales, filters and translates the surgeon's hand movements into more precise micro-movements of the instruments, which operate through small incisions in the body.
According to the manufacturer, the da Vinci System is called "da Vinci" in part because Leonardo da Vinci invented the first robot. The artist Leonardo also used anatomical accuracy and three-dimensional details to bring his works to life.
To perform a procedure, the surgeon uses the console’s master controls to maneuver the patient-side cart’s three or four robotic arms (depending on the model), which secures the instruments and a high-resolution endoscopic camera. The instruments’ jointed-wrist design exceeds the natural range of motion of the human hand; motion scaling and tremor reduction further interpret and refine the surgeon’s hand movements. The da Vinci System incorporates multiple, redundant safety features designed to minimize opportunities for human error when compared with traditional approaches. At no time is the surgical robot in control or autonomous; it operates on a "Master:Slave" relationship, the surgeon being the "Master" and the robot being the "Slave."
The da Vinci System has been designed to improve upon conventional laparoscopy, in which the surgeon operates while standing, using hand-held, long-shafted instruments, which have no wrists. With conventional laparoscopy, the surgeon must look up and away from the instruments, to a nearby 2D video monitor to see an image of the target anatomy. The surgeon must also rely on his/her patient-side assistant to position the camera correctly. In contrast, the da Vinci System’s ergonomic design allows the surgeon to operate from a seated position at the console, with eyes and hands positioned in line with the instruments. To move the instruments or to reposition the camera, the surgeon simply moves his/her hands.
By providing surgeons with superior visualization, enhanced dexterity, greater precision and ergonomic comfort, the da Vinci Surgical System makes it possible for more surgeons to perform minimally invasive procedures involving complex dissection or reconstruction. For the patient, a da Vinci procedure can offer all the potential benefits of a minimally invasive procedure, including less pain, less blood loss and less need for blood transfusions. Moreover, the da Vinci System can enable a shorter hospital stay, a quicker recovery and faster return to normal daily activities.
The robot costs on average $1.3 million in addition to several hundred thousand dollars of annual maintenance fees. Surgical procedures performed with the robot take longer than traditional ones. Critics have pointed out that hospitals have a hard time recovering the cost and that most clinical data does not support the claim of improved patient outcomes

Drug delivery

Drug delivery is a process, during which pharmaceutical compounds are delivered to humans or animals. Methods of delivery include several routs, such as oral, nasal, pneumonial, rectal and several others. In order to work effectively, the drug needs to work in a controlled manner, which would control the circulation of the drug in the body. Targeted delivery occurs when the drug remains active within a specified territory of the body. Targeted drug delivery is especially important in cases, when the drug needs to affect a malicious turmoil, such as in cancerous tissues.
Doctors all over the world are trying to find new methods for more effective drug development and drug delivery. One of the most successful methods developed in recent years is nanotechnology. This mechanism, which controls small-scale matter, makes it possible for drugs to permeate trough cell walls. The methods of nanotechnology play a very important role in pharma industry: health organizations manufacture more efficient drugs, released in a controlled manner in order to reach the target areas of the patients' body.
Drug development aims to find more effective drugs, which would cure or ameliorate symptoms of illness or medical condition. Drug development is required to establish the chemical properties of new compounds, their stability and chemical makeup. The process of drug development also involves the need to fit the regulatory requirements of drug licensing authorities. Pharmaceutical companies, which produce different medications, develop new methods of targeted drug delivery. Nanotechnology, developed in recent years may provide a breakthrough technique of drug delivery.
Submitted by Natalie Halimi - Content Editor in Internet Marketing Company - Inter-Dev http://www.inter-dev.co.il/en/ Drug delivery, drug development - http://www.docoop.com/

Release of neurological drugs

Drug Delivery Systems
Markets and Applications for Nanotechnology Derived Drug Delivery Systems
Background
The most promising aspect of pharmaceuticals and medicine as it relates to nanotechnology is currently drug delivery. In the words of LaVan and Langer: ‘It is likely that the pharmaceutical industry will transition from a paradigm of drug discovery by screening compounds to the purposeful engineering of targeted molecules.’

Reasons Why the Drug Delivery Market is Rapidly Expanding
At present, there are 30 main drug delivery products on the market. The total annual income for all of these is approximately US$33 billion with an annual growth of 15% (based on global product revenue). Two major drivers are primarily responsible for this increase in the market. First, present advances in diagnostic technology appear to be outpacing advances in new therapeutic agents. Highly detailed information from a patient is becoming available, thus promoting much more specific use of pharmaceuticals. Second, the acceptance of new drug formulations is expensive and slow, taking up to 15 years to obtain accreditation of new drug formulas with no guarantee of success.

How Drug Companies are Reacting to this Expansion
In response, some companies are trying to hurry the long clinical phase required in Western medicine. However, powerful incentives remain to investigate new techniques that can more effectively deliver or target existing drugs (Saxl, 2000). In addition, many of these new tools will have foundation in current techniques: a targeted molecule may simply add spatial or temporal resolution to an existing assay. Thus, although many potential applications are envisaged, the actual near future products are not much more than better research tools or aids to diagnosis. These are summarised in the following three tables.

More details see >> AZoNanotechnology Article

Biosciences and Biomedical Engineering

Demand for interdisciplinary laboratories for physiology research by undergraduate students in biosciences and biomedical engineering
Kari L. Clase1, Patrick W. Hein2 and Nancy J. Pelaez

1 Department of Industrial Technology and Bindley Bioscience Center, West Lafayette, Indiana
2 Department of Basic Medical Sciences and Weldon School of Biomedical Engineering, West Lafayette, Indiana
3 Department of Biological Sciences, Purdue University, West Lafayette, Indiana
Address for reprint requests and other correspondence: K. L. Clase, Dept. of Industrial Technology, Bindley Bioscience Center, Purdue Univ., West Lafayette, IN 47907
(e-mail: klclase@purdue.edu)

Abstract
Physiology as a discipline is uniquely positioned to engage undergraduate students in interdisciplinary research in response to the 2006–2011 National Science Foundation Strategic Plan call for innovative transformational research, which emphasizes multidisciplinary projects. To prepare undergraduates for careers that cross disciplinary boundaries, students need to practice interdisciplinary communication in academic programs that connect students in diverse disciplines. This report surveys policy documents relevant to this emphasis on interdisciplinary training and suggests a changing role for physiology courses in bioscience and engineering programs. A role for a physiology course is increasingly recommended for engineering programs,
but the study of physiology from an engineering perspective might differ from the study of physiology as a basic science. Indeed, physiology laboratory courses provide an arena where biomedical engineering and bioscience students can apply knowledge from both fields while cooperating in multidisciplinary teams under specified technical constraints. Because different problem-solving approaches are used by students of engineering and bioscience, instructional
innovations are needed to break down stereotypes between the disciplines and create an educational environment where interdisciplinary teamwork is used to bridge differencesKey words: laboratory education; engineering education; physiology education; design thinking

>More information:

Advances in Biomedical Engineering

Advances in Biomedical Engineering
Linda G. Griffith, PhD; Alan J. Grodzinsky, ScD
JAMA. 2001;285:556-561.

The most visible contributions of biomedical engineering to clinical practice involve instrumentation for diagnosis, therapy, and rehabilitation. Cell and tissue engineering also have emerged as clinical realities. In the next 25 years, advances in electronics, optics, materials, and miniaturization will accelerate development of more sophisticated devices for diagnosis and
therapy, such as imaging and virtual surgery. The emerging new field of bioengineering—engineering based in the science of molecular cell biology—will greatly expand the scope of biomedical engineering to tackle challenges in molecular and genomic medicine.
Author Affiliations: Division of Bioengineering and Environmental Health, Departments of Electrical (Dr Grodzinsky), Mechanical (Dr Grodzinsky), and Chemical Engineering (Dr Griffith),Center for Biomedical Engineering, Massachusetts Institute of Technology, Cambridge.

> More Informations :

Lab on a chip

Lab on a chip mimics brain chemistry

February 12th, 2008 Johns Hopkins researchers from the Whiting School of Engineering and the School of Medicine have devised a micro-scale tool – a lab on achip – designed to mimic the chemical complexities of the brain. The system should help scientists better understand how nerve cells in the brain work together to form the nervous system.
AmpliChip CYP450 Test – www.AmpliChip.us
Roche Diagnostics US Official Site FDA cleared CYP450 Test

A report on the work appears as the cover story in the February 2008 issue of the British journal Lab on a Chip. ”The chip we’ve developed will make xperiments on nerve cells more simple to conduct and to control,” says Andre Levchenko, Ph.D., associate professor of biomedical engineering at the Johns Hopkins Whiting School of Engineering and faculty affiliate of the Institute for NanoBioTechnology. Nerve cells decide which direction to grow by sensing both the chemical cues flowing through their environment as well as those attached to the surfaces that surround them. The chip, which is made of a plastic-like substance and covered with a glass lid, features a system of channels and wells that allow researchers to control the flow of specific chemical cocktails around single nerve cells.

“It is difficult to establish ideal experimental conditions to study how neurons react to growth signals because so much is happening at once that sorting out nerve cell connections is hard, but the chip, designed by experts in both brain chemistry and engineering, offers a sophisticated way to sort things out,” says Guo-li Ming,
M.D.,Ph.D., associate professor of neurology at the Johns Hopkins School of Medicine and Institute for Cell Engineering.

In experiments with their chip, the researchers put single nerve cells, or rons,onto the chip then introduced specific growth signals (in the form of hemicals).They found that the growing neurons turned and grew toward higher concentrations of certain chemical cues attached to the chip’s surfaces, as well as to signaling molecules free-flowing in solution.

When researchers subjected the neurons to conflicting signals (both surface bound and cues in solution), they found that the cells turned randomly, suggesting that cells do not choose one signal over the other. This,according to Levchenko,supports the prevailing theory that one cue can elicit different responses depending on
a cell’s surroundings. “The ability to combine several different stimuli in the chip resembles a more realistic environment that nerve cells will encounter in the living animal,” Ming says.This in turn will make future studies on the role of neuronal cells in development and regeneration more accurate and complete.

Source: Johns Hopkins Medical Institutions