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PubMed1990

Organ and tissue procurement in the acute care setting: principles and practice--Part 1.

The specialty of organ transplantation has grown tremendously during the past decade. With the advent of cyclosporine, artificial organs, and organ-assist devices, the possibility of suitable patients with end-stage organ disease becoming successful transplant recipients has increased dramatically. Consequently, the need for donor organs has risen. The greatest source of potential organ-tissue donors exists in the acute care setting (ie, emergency departments and intensive care units). To meet the need for this increasing demand, emergency physicians must become familiar with the techniques of procurement. Part 1 defines the problem of procurement and presents financial, historic, organizational, legal, and psychosocial aspects of organ-tissue procurement. A synopsis of brain death concludes the discussion. Part 2 (February 1990) presents aspects of the evaluation, selection, maintenance, and management of the organ-tissue donor. Disease transmission and controversial issues in organ-tissue procurement also are discussed.

Brain Death↗
PubMed1998

Cure of Goodpasture's disease.

Goodpasture's Disease is an explosive multisystem disease presenting initially as a pulmonary-renal syndrome. There is often little margin for error in making an early correct diagnosis to avoid respiratory and renal failure. Complications of invasive diagnostic testing and aggressive immunosuppressive treatment often lead to other organ dysfunction due to infection, hemodynamic disturbances, fluid and electrolyte challenges, and nutritional deficiency. Artificial organ therapy is often needed for pulmonary and renal support, for immunomodulation, and for nutritional replacement. The outcome is often considered satisfactory if the patient survives the acute presentation. Persistent organ failure is quite often the case, especially renal failure. Quality of life is often improved if there is subsequent renal transplantation. By then the patient may be considered "cured". Two cases are described below, contrasting young and elderly white females both in previous good health who developed rapid onset of Goodpasture's disease. One was cured after transplantation, and one was cured without transplantation. The severity of the renal involvement was the same for both patients. Cure of Goodpasture's Disease in the native kidneys is uncommon; a review of the literature is provided.

Adult↗
PubMed1998

[Organ donation in France. Current situation and perspectives].

RECENT CRISIS: Strict legal regulations concerning human organ procurement in France emphasize the positive aspect of donation. While public opinion in France is generally favorable, organ donation passed through a crisis during the period between 1990 and 1994. The media played a crucial role. CONFIDENCE AND COORDINATED EFFORTS: The Etablissement français des Greffes, in coordination with health care workers and non-governmental organizations, has developed a wide health education program aimed at gaining the confidence of the public and organizing hospital efforts to create an effective and serene procurement procedure. PERSPECTIVES: Procurement of cadaver organs remains essential despite the number of living-donors and ongoing development of artificial organs and xenografts.

France↗
PubMed2006

Electrokinetic migration across artificial liquid membranes Tuning the membrane chemistry to different types of drug substances.

Twenty different basic drugs were electrokinetically extracted across a thin artificial organic liquid membrane with a 300 V d.c. electrical potential difference as the driving force. From a 300 microl aqueous sample (acidified corresponding to 10mM HCl), the drugs were extracted for 5 min through a 200 microm artificial liquid membrane of a water immiscible organic solvent immobilized in the pores of a polypropylene hollow fiber, and into a 30 microl aqueous acceptor solution of 10mM HCl inside the lumen of the hollow fiber. Hydrophobic basic drugs (logP>1.7) were effectively isolated utilizing 2-nitrophenyl octyl ether (NPOE) as the artificial liquid membrane, with recoveries up to 83%. For more hydrophilic basic drugs (logP<1.0), a mixture of NPOE and 25% (w/w) di-(2-ethylhexyl) phosphate (DEHP) was required to ensure efficient extraction, resulting in recoveries up to 75%. DEHP was expected to act as an ion-pair reagent ion-pairing the protonated hydrophilic drugs at the interface between the sample and the membrane, resulting in permeation of the interface.

Chromatography, Micellar Electrokinetic Capillary↗
PubMed1998

International issues in transplantation. Setting the scene and flagging the most urgent and controversial issues.

Organ transplantation is the primary technique for treatment of end-stage organ failure and has benefited more than one million persons world wide. A number of patients have survived for well over 25 years and survival rates at 5 years can be 70% or higher for many organ transplant programs. However, currently more than 40,000 patients are waiting for a kidney, and in western Europe mortality rates for patients waiting for a heart, liver, or lung range from 15 to 30%. The potential need for transplants is even greater and this imbalance between supply and demand creates technical and ethical problems including the risk of organ trafficking. Consequently the number of available organs must be increased. In some cases the organ shortage reflects a true lack of donors, but more often it results from the failure to turn potential into actual donors. The transplant commission of the Council of Europe has just approved a document recommending that member states ensure that all potential donors are identified and as many as possible converted to actual donors. Even with the highest organ donation rate, the indications for organ and tissue transplantation will continue to increase, perpetuating the gap between supply and demand. Organ transplantation, whether living or cadaveric, might be supplemented or replaced by the use of artificial organs, although problems such as power supply, thrombosis, infection, and biocompatibility pose obstacles to long-term function. The use of animals as an alternative source is considered, but so many problems still remain unresolved that xenotransplantation cannot be put forth as a solution at this time. This paper reviews these issues and, citing the Spanish experience, offers strategies to improve the organ donation rate.

Ethics, Medical↗
PubMed2004

Design of novel biointerfaces (II). Fabrication of self-organized porous polymer film with highly uniform pores.

Application of porous polymer materials to novel bio-interfaces for tissue engineering scaffold and artificial organs including blood filters, dialyzer, and oxygenator membranes have been in progress. The present study describes the fabrication and characterization of self-organized highly regular porous polymer films with uniform pore sizes are prepared by simple casting technique. Various fabrication parameters affecting the pore size such as polymer concentration, boiling point of solvent, cast volume and substrate are studied. The pore size can be controlled in the range from 1 to 50 microm by changing the evaporation rate of the polymer solutions. The porous film with uniform pore size is used for tissue engineering scaffold and cell separation membrane. To simulate the leukocyte eliminating from human blood, the porous film was attached to a module. The films with 5-9 microm pores provided the complete selectivity of separation for the leukocyte from the whole blood. The leukocyte elimination ratio depends on pore structures (size and depth) as well as recovery of platelet and erythrocyte.

Acrylamides↗
PubMed2006

Production of hydrogen and methane from organic solid wastes by phase-separation of anaerobic process.

Phase-separated two-stage anaerobic process was examined and evaluated using artificial organic solid waste in laboratory scale. Acidogenic process, which was combined with subsequent methanogenic process using packed-bed reactor, was operated emphasizing on either hydrogen production, or solublizing efficiency of solid materials. In either effluent from hydrogenogenic, or solublizing operation, maximum allowable OLR achieved at methanogenesis was higher than the single methanogenic process. Hydrogenogenic operation was more suitable to combine methanogenic process than solublizing operation, since retention time of hydrogenogenic operation was much shorter than the solublizing operation, obtaining almost the same levels of overall removal efficiency in both COD and VSS. The combination of hydrogenogenic operation in acidogenic process and methanogenic process produced approximately 442mmoll-reactor(1)days(-1) of methane and 199mmoll-reactor(1)days(-1) of hydrogen at 25h of total retention time indicating 82% of COD removal with 96% of VSS decomposition.

Anaerobiosis↗
PubMed2006

Indian Society for Apheresis and apheresis tourism in India--is there a future?

Apheresis has now become an internationally popular mode of treatment for multiple immune complex disorders. However, the treatment remains quite expensive in Western Europe and the US. Apheresis tourism is a part of medical tourism or medical tourism specially related to therapeutic apheresis (TA) treatment in a foreign country on a cost effective basis. In the last couple of years, 'Medical Tourism' has become an upcoming and growing enterprise in India. The Indian Society for Apheresis (ISA) has taken a plunge at the opportune time and is trying to promote apheresis tourism in India. ISA is a member of various international apheresis organizations globally including the World Apheresis Association (WAA), the International Society for Apheresis (ISFA), the International Society for Artificial Organs (ISAO) and an associate of other national apheresis societies. The Indian Society for Apheresis (ISA) and the Ludhiana MediCiti (LMC) at Ludhiana Punjab are taking a big step in this direction. The therapeutic apheresis (TA) center at LMC is being set up as a Therapeutic Apheresis Institute and Research Center of excellence. The potential future impacts on the apheresis scenario are summarized.

Autoimmune Diseases↗
PubMed1986

The current status of mechanical circulatory support.

In summary, techniques for support of a failing circulation have advanced steadily over the past thirty years. Just as the use of the intra-aortic balloon pump has permitted successful treatment of certain groups of high-risk patients, so increasing application of more invasive techniques of mechanical circulatory support has extended the range of surgical endeavour. Nevertheless, it is evident that further advances in the design and construction of mechanical circulatory support devices are most likely to occur in conjunction with developments in bioengineering technology. These advances will in turn demand analysis by means of careful animal and clinical investigations. Although the general clinical use of an off-the-shelf mechanical ventricular support will give rise to major financial and ethical problems it is likely that application of these devices may herald a new era in the field of artificial organ replacement.

Assisted Circulation↗
PubMed2002

Role of complement in xenotransplantation.

The xenotransplantation research is driven by the increasing gap between the number of patients with end-stage organ failure on waiting lists for transplantation and the supply of allografts. The lack of success in developing suitable artificial organs for permanent treatment of organ failure has further strengthened the need for xenotransplantation research. Pigs are now generally accepted to be the source animal of choice. Transplantation of pig organs to humans faces several barriers which have to be overcome before it comes to clinical application: (1) anatomical and physiological conditions; (2) immunological rejection mechanisms; (3) molecular compatibility between signal molecules of the two species; (4) risk of transmission of microorganisms, particularly pig endogenous retroviruses; and (5) legal and ethical aspects both with respect to the animal and the recipient. Here we will focus on the role of the complement system in the rejection of immediately vascularized pig-to-primate xenografts. The hyperacute rejection occurring within minutes after transplantation is mediated by binding of natural antibodies to the Galalpha(l-3)Gal epitope on the endothelial cells with subsequent complement activation. Whereas inhibition of complement activation protects against hyperacute rejection, the role of complement in the later rejection phases is less clarified.

Animals↗
PubMedDate not supplied

[Use of the method of selective catheterization of the heart and major vessels in biomedical research with the participation of healthy persons].

The paper discusses the application of direct techniques to the study of circulation--catheterization of the heart and central vessels in biomedical experiments with the participation of healthy volunteers and during examinations of pilots, athletes, etc. The experiments showed high informativeness and reliability of the techniques and demonstrated their applicability to the study of gravity effects on the circulation and metabolism of different organs of healthy men as applied to aerospace and clinical medicine. These investigations allow clinical modelling of hemodynamic and metabolic changes that may develop in various organs and tissues in weightlessness, development of pathogenetically substantiated countermeasures against its adverse effects, formulation of certain requirements for artificial organs whose function should be as close as possible to that of natural organs of a healthy man. The paper presents the protocol and results of the first study of the effects of short-term simulated weightlessness on the circulation and metabolism of various organs of a healthy man: brain, heart, lungs, liver, kidneys, and musculoskeletal formations of the lower limbs.

Blood Circulation↗
PubMedDate not supplied

Strategies for cell engineering in tissue repair.

Cellular and tissue engineering are new areas of research, currently attracting considerable interest because of the remarkable potential they have for clinical application. Some claims have indeed been dramatic, including the possibility of growing complete, artificial organs, such as the liver. However, amid such long-term aspirations there is the very real possibility that small tissues (artificial grafts) may be fabricated in the near future for use in reconstructive surgery. Logically, we should focus on how it is possible to produce modest, engineered tissues for tissue repair. It is evident that strategies to date either depend on innate information within implanted cells, to reform the target tissue or aim to provide appropriate environmental cues or guidance to direct cell behavior. It is argued here that present knowledge of tissue repair biology points us toward the latter approach, providing external cues which will direct how cells should organize the new tissue. This will be particularly true where we need to reproduce microscopic and ultrastructural features of the original tissue architecture. A number of such cues have been identified, and methods are already available, including substrate chemistry, substrate contact guidance, mechanical loading, and biochemical mediators to provide these cues. Examples of these are already being used with some success to control the formation of tissue structures.

Journal Article↗
PubMed1999

Critical care apheresis: hepatic failure.

Hepatic failure is a common feature of critical care. Most hepatic dysfunction in the ICU responds to medical management and metabolic support. The role of extracorporeal organ support in hepatic failure is not as well defined as it is in renal failure and pulmonary failure. Nevertheless, artificial organ support has been successful in the treatment of advanced liver failure. Hybrid bioartificial liver substitutes show great promise, especially as a bridge to liver transplant.

Blood Component Removal↗
PubMed1982

In vitro evaluation of U.S. and U.S.S.R. artificial hearts.

This report summarizes the results of the in vitro evaluation of Soviet and American artificial hearts. The devices were tested at the All-Union Institute of Transplantation and Artificial Organs, Moscow, U.S.S.R., and Baylor College of Medicine, Houston, Texas, U.S.A. These studies were designed to standardize procedures to allow comparison of artificial ventricles of different designs. Also, these studies might provide a means for evaluation of other characteristics such as hemolysis, durability, and reliability. Static and dynamic tests were performed, varying preload, afterload, rate, and systolic and diastolic time intervals. All designs demonstrated comparable function curves with capability of taking over the pressure and volume work of the natural heart.

Blood Flow Velocity↗
PubMed2006

Electrokinetic migration across artificial liquid membranes. New concept for rapid sample preparation of biological fluids.

Basic drug substances were transported across a thin artificial organic liquid membrane by the application of 300 V d.c. From a 300 microl aqueous donor compartment (containing 10 mM HCl), the drugs migrated through a 200 microm artificial liquid membrane of 2-nitrophenyl octyl ether immobilized in the pores of a polypropylene hollow fiber, and into a 30 microl aqueous acceptor solution of 10 mM HCl inside the lumen of the hollow fiber. The transport was forced by an electrical potential difference sustained over the liquid membrane, resulting in electrokinetic migration of drug substances from the donor compartment to the acceptor solution. Within 5 min of operation at 300 V, pethidine, nortriptyline, methadone, haloperidol, and loperamide were extracted with recoveries in the range 70-79%, which corresponded to enrichments in the range 7.0-7.9. The chemical composition of the organic liquid membrane strongly affected the permeability, and may serve as an efficient tool for controlling the transport selectivity. Water samples, human plasma, and human urine were successfully processed, and in light of the present report, electrokinetic migration across thin artificial liquid membranes may be an interesting tool for future isolation within chemical analysis.

Chromatography, Micellar Electrokinetic Capillary↗
PubMed2000

Tissue restoration, tissue engineering and regenerative medicine.

Recently, thanks to the rapid progress of new technologies in cell modulation, extracellular matrix fabrication and synthetic polymers mimicking bodily structures, the self-regeneration of bodily defects by host tissue has been considered by many researchers. The conventional science of art in biomaterials has been concerned with restoring damaged tissue using non-biological materials such as metals, ceramics and synthetic polymers. To overcome the limitations of using such non-viable materials, several attempts to construct artificial organs mimicking natural tissue by combining modulated cells with extracellular matrix-hybridized synthetic polymers have produced many worthy results with biologically functioning artificial tissues. The process involved in manufacturing biomaterials mimicking living tissue is generally called tissue engineering. However recently, the extension of knowledge about cell biology and embryology has naturally moved the focus from tissue restoration to tissue regeneration. Especially, embryonic and mesenchymal stem cells are attractive resources due to their potential for the differentiation of various tissue cells in response to signal transduction mediated by cytokines. Although no one knows yet what is the exact factor responsible for a stem cell's ability to differentiate between specific cells to generate specific tissue, what has been agreed is that delivering stem cells into the body provides a strong potential for the regeneration of tissue. In this review, the historical issues and future possibilities involved in medical tissue restoration and tissue regeneration are discussed.

Animals↗
PubMedDate not supplied

Understanding of and attitudes to organ donation and transplantation: a survey among Italian university students.

BACKGROUND: Students have a positive attitude to organ donation and transplantation, usually associated with their personal willingness to donate their organs after death. The aim of this study was to evaluate the opinions of university students on transplantation and organ donation, at a single Italian university. METHODS: University undergraduates attending the first year on five different courses in 2001 were surveyed at Padua University by using an anonymous 13-item questionnaire. RESULTS: 97.2% of the students completed the questionnaire (77.4% females, mean age 20.4 yr); they were attending Medicine (33.8%), Agriculture (5.9%), Veterinary Medicine (11.4%), Psychology (18.5%) and Educational Sciences (30.4%). The majority was aware of the problem of the paucity of organ donations and deaths on the waiting list in Italy. Most students would accept transplantation in the case of a human donor (97%), an artificial organ (95%) or an animal donor (76%); and 87% of them were prepared to donate their own organs after death. No differences were seen when students attending science courses were compared with those attending art courses. Italian university students have a very positive attitude and willingness to donate their own organs after death, with no differences emerging as regards type of university education.

Adult↗