Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31
Filtrar
1.
Reprod Biomed Online ; 43(4): 581-585, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34465527

RESUMEN

Biovigilance is the systematic monitoring of serious adverse reactions and events (SARE) that ensures the quality and safety of tissues and cells for human application in medically assisted reproduction (MAR). The Notify Library is an open access database launched by the World Health Organization and supported by the Italian National Transplant Centre (CNT) that has collected information on documented adverse occurrences in transplantation, transfusion and MAR. It is not a SARE register, but rather a collection of SARE types identified primarily by review of published articles and case reports from national or regional vigilance programmes. The Notify Library includes many well-documented records of adverse occurrences in MAR treatment, representing a useful tool for MAR operators in the evaluation of the risks associated with the clinical application of reproductive tissues and cells. It is updated with new records when a new type of incident is reported for the first time. All incident types described might have teaching value during the risk management carried out by a MAR centre. Sharing lessons learned from these incidents represents an important didactic opportunity that can help MAR centres to improve their processes and to achieve higher standards of quality and safety.


Asunto(s)
Técnicas Reproductivas Asistidas/efectos adversos , Gestión de Riesgos/organización & administración , Humanos , Aprendizaje
2.
Cell Tissue Bank ; 19(2): 187-195, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28667461

RESUMEN

This issue is dedicated to the contributions of Professor Glyn O. Phillips to the field of tissue banking and the advancement of science in general. The use of ionizing radiation to sterilize medical products drew the interest of the International Atomic Energy Agency (IAEA). A meeting in 1976 in Athens Greece to present work on the effects of sterilizing radiation doses upon the antigenic properties of proteins and biologic tissues was my first introduction of Professor Phillips and the role that he was to play in Tissue Banking (Friedlaender, in Phillips GO, Tallentine AN (eds) Radiation sterilization. Irradiated tissues and their potential clinical use. The North E. Wales Institute, Clwyd, p 128, 1978). The IAEA sponsored subsequent meetings in the Republic of Korea, Czechoslovakia and Rangoon, the later including a visit to the tissue bank by Professor Phillips. His advocacy resulted in multiple workshops and teaching opportunities in a variety of countries, one of which led to the establishment of the Asia Pacific Surgical Tissue Banking Association in 1989 (Phillips and Strong, in Phillips GO, Strong DM, von Versen R, Nather A (eds) Advances in tissue banking, vol 3. World Scientific, Singapore, pp 403-417, 1999).


Asunto(s)
Agencias Internacionales/historia , Bancos de Tejidos/historia , Recolección de Tejidos y Órganos/historia , Trasplantes/historia , Historia del Siglo XX , Humanos , Radiación Ionizante , Esterilización/historia
4.
Cell Tissue Bank ; 11(4): 335-43, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20652419

RESUMEN

The US lags behind other developed countries in creating a system to monitor disease transmission and other complications from human allograft use, despite a pressing need. The risks of transmission are amplified in transplantation, since at least 8 organs and more than 100 tissues can be recovered from a single common organ and tissue donor. Moreover, since many allografts collected in the US are distributed internationally, tissue safety is a global concern. In June 2005, participants of a US government-sponsored workshop concluded that a communication network for the tracking and reporting of disease transmissions for tissues and organs was critically needed. The United Network for Organ Sharing (UNOS) entered into a cooperative agreement with the Centers for Disease Control and Prevention (CDC) in 2006 to develop a system prototype. Over the following 3 years, the Transplantation Transmission Sentinel Network (TTSN) was developed and piloted with the participation of organ procurement organizations, tissue banks and transplant centers. The prototype centered around three elements of data entry: (1) donation, (2) tissue implantation, and (3) adverse event. The pilot proved that a system can be built and operated successfully, but also suggested that users may be hesitant to report adverse events. CDC has requested further input on scope and cost to build a transplant surveillance infrastructure for a fully functional national system. For tissues however, in contrast to organs, tracking from recovery to implantation will be necessary before a system is operable, requiring common identifiers and nomenclature. Until a US sentinel network is operational, future transmission events that are preventable may result nationally and globally due to its absence.


Asunto(s)
Trasplante de Órganos , Garantía de la Calidad de Atención de Salud , Trasplante de Tejidos , Obtención de Tejidos y Órganos/normas , Transmisión de Enfermedad Infecciosa/prevención & control , Procesamiento Automatizado de Datos , Humanos , Trasplante de Órganos/efectos adversos , Vigilancia de la Población , Riesgo , Seguridad , Bancos de Tejidos , Donantes de Tejidos , Trasplante de Tejidos/efectos adversos , Estados Unidos
5.
Cell Tissue Bank ; 11(4): 305-23, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20464502

RESUMEN

Modern transplantation of cells, tissues and organs has been practiced within the last century achieving both life saving and enhancing results. Associated risks have been recognized including infectious disease transmission, malignancy, immune mediated disease and graft failure. This has resulted in establishment of government regulation, professional standard setting and establishment of vigilance and surveillance systems for early detection and prevention and to improve patient safety. The increased transportation of grafts across national boundaries has made traceability difficult and sometimes impossible. Experience during the first Gulf War with mis-identification of blood units coming from multiple countries without standardized coding and labeling has led international organizations to develop standardized nomenclature and coding for blood. Following this example, cell therapy and tissue transplant practitioners have also moved to standardization of coding systems. Establishment of an international coding system has progressed rapidly and implementation for blood has demonstrated multiple advantages. WHO has held two global consultations on human cells and tissues for transplantation, which recognized the global circulation of cells and tissues and growing commercialization and the need for means of coding to identify tissues and cells used in transplantation, are essential for full traceability. There is currently a wide diversity in the identification and coding of tissue and cell products. For tissues, with a few exceptions, product terminology has not been standardized even at the national level. Progress has been made in blood and cell therapies with a slow and steady trend towards implementation of the international code ISBT 128. Across all fields, there are now 3,700 licensed facilities in 66 countries. Efforts are necessary to encourage the introduction of a standardized international coding system for donation identification numbers, such as ISBT 128, for all donated biologic products.


Asunto(s)
Transfusión Sanguínea/normas , Procesamiento Automatizado de Datos/normas , Obtención de Tejidos y Órganos/normas , Trasplantes/normas , Guías como Asunto , Humanos , Registros Médicos/normas , Trasplante de Órganos/normas , Riesgo , Bancos de Tejidos , Donantes de Tejidos , Trasplante de Tejidos/normas , Organización Mundial de la Salud
6.
Cell Tissue Bank ; 11(3): 269-80, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19565355

RESUMEN

It is well accepted that human umbilical cord blood (UCB) is a source of mesenchymal stem cells (MSCs) which are able to differentiate into different cell phenotypes such as osteoblasts, chondrocytes, adipocytes, myocytes, cardiomyocytes and neurons. The aim of this study was to isolate MSCs from human UCB to determine their osteogenic potential by using different kinds of osteogenic medium. Eventually, only those MSCs cultured in osteogenic media enriched with vitamin D(2) and FGF9, were positive for osteocalcin by RT-PCR. All these cells were positive for alizarin red, alkaline phosphatase and Von Kossa. The results obtained from RT-PCR have confirmed that osteogenesis is complete by expression of the osteocalcin marker. In conclusion, vitamin D(2), at least in vitro, may replace vitamin D(3) as an osteogenic stimulator factor for MSC differentiation.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Diferenciación Celular , Sangre Fetal/citología , Osteoblastos/citología , Biomarcadores/metabolismo , Diferenciación Celular/efectos de los fármacos , Forma de la Célula/efectos de los fármacos , Células Cultivadas , Medios de Cultivo/farmacología , Ergocalciferoles/farmacología , Factor 9 de Crecimiento de Fibroblastos/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/efectos de los fármacos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Osteocalcina/genética , Osteocalcina/metabolismo , Osteogénesis/efectos de los fármacos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
7.
Cell Tissue Bank ; 10(3): 271-80, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19016348

RESUMEN

A workshop in June 2005 ("Preventing Organ and Tissue Allograft-Transmitted Infection: Priorities for Public Health Intervention") identified gaps in organ and tissue safety in the US. Participants developed a series of allograft safety initiatives. "The Organ and Tissue Safety Workshop 2007: Advances and Challenges" assessed progress and identified priorities for future interventions. Awareness of the challenges of allograft-associated disease transmission has increased. The Transplantation Transmission Sentinel Network will enhance communication surrounding allograft-associated disease transmission. Other patient safety initiatives have focused on adverse event reporting and microbiologic screening technologies. Despite progress, improved recognition and prevention of donor-derived transmission events is needed. This requires systems integration across the organ and tissue transplantation communities including organ procurement organizations, eye and tissue banks, and transplant infectious disease experts. Commitment of resources and improved coordination of efforts are required to develop essential tools to enhance safety for allograft recipients.


Asunto(s)
Transmisión de Enfermedad Infecciosa/prevención & control , Selección de Donante/normas , Bancos de Tejidos/normas , Donantes de Tejidos , Trasplante de Tejidos/efectos adversos , Humanos
8.
Transfusion ; 48(11): 2315-22, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18647367

RESUMEN

BACKGROUND: Blood donor testing for antibody to hepatitis B core antigen (anti-HBc) has been used in the United States for more than 20 years as a surrogate to prevent transmission by transfusion of non-A, non-B hepatitis, as a human immunodeficiency virus surrogate, and to reduce transmission of hepatitis B virus (HBV). Nonspecific anti-HBc assays have caused deferral of hundreds of thousands of otherwise qualified donors. A more specific anti-HBc test and a sensitive HBV DNA test should permit donor reentry after false-positive anti-HBc. STUDY DESIGN AND METHODS: A total of 1324 otherwise eligible volunteer donors, deferred for anti-HBc reactivity on more than one occasion, were recruited from four collection facilities. They were tested using a licensed, more specific anti-HBc test, a licensed hepatitis B surface antigen (HBsAg) test, and a licensed HBV DNA assay with a 95 percent limit of detection of not more than 10 copies per mL. RESULTS: From 11 to 32 percent of donors contacted by participating sites entered the study. Overall, 488 (37%) of the donors were negative on the more specific anti-HBc test. The proportion of putative false-positive samples varied according to the test responsible for the original deferral. A single donor, negative for the presence of anti-HBc and HBsAg, was positive for the presence of HBV DNA in one of three replicates. Repeat testing of this donor 10 months later was negative for the presence of all markers of HBV infection, and the donor had a history of HBV vaccination with documented postimmunization anti-HBs seroconversion 10 years before her anti-HBc deferral, and was considered HBV DNA false positive. CONCLUSION: These data support reentry of donors with false-positive anti-HBc results on the relatively nonspecific assays that have been in use in the United States for more than 20 years.


Asunto(s)
Algoritmos , Bancos de Sangre/normas , Donantes de Sangre , ADN Viral/sangre , Anticuerpos contra la Hepatitis B/sangre , Antígenos del Núcleo de la Hepatitis B/inmunología , Hepatitis B/prevención & control , Tamizaje Masivo/normas , Adulto , Errores Diagnósticos , Reacciones Falso Positivas , Femenino , Hepatitis B/sangre , Hepatitis B/diagnóstico , Hepatitis B/inmunología , Humanos , Masculino , Guías de Práctica Clínica como Asunto , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estados Unidos , United States Food and Drug Administration , Voluntarios
9.
Transfusion ; 48(7): 1376-82, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18422847

RESUMEN

BACKGROUND: Hepatitis B virus (HBV) residual risk has been estimated at 1:63,000-1:205,000 and introduction of more sensitive serological tests and nucleic acid testing (NAT) would reduce that risk. Sensitivity of the recently licensed Abbott PRISM hepatitis B surface antigen (HBsAg) CLIA and minipool (MP) HBV NAT has been described as comparable and thus the need for HBV NAT has not been compelling. In this study, eight samples identified as yield samples with MP HBV NAT were tested using the PRISM test. STUDY DESIGN AND METHODS: Seven samples were identified using the Roche COBAS AmpliScreen HBV test and one additional sample was obtained from the clinical trial for the Roche cobas TaqScreen MPX test. Each of these samples was reactive by MP HBV NAT and nonreactive for HBsAg using one of three licensed enzyme immunoassay (EIA) tests. After licensure of the PRISM HBsAg, aliquots were tested with this assay, and DNA quantitation and genotyping were repeated where sample volume permitted. RESULTS: Three samples (2000, 2300, and 61,000 copies/mL) produced reactive results with PRISM. Four samples with viral loads less than 300 copies per mL produced nonreactive results. One sample, originally quantitated at 37,000 copies per mL (but 3850 copies/mL in repeat testing) was also nonreactive by PRISM. Genotyping of this sample indicated a type C genotype with no mutations. CONCLUSION: Adding serological sensitivity of PRISM CLIA reduced the NAT yield from the original 1: 385,555 to 1:610,488. However, MP HBV NAT still provides additional sensitivity over CLIA, even for a donation with a viral load of almost 4000 copies per mL.


Asunto(s)
Antígenos de Superficie de la Hepatitis B/análisis , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/inmunología , Donantes de Sangre , ADN Viral/química , ADN Viral/genética , Genotipo , Hepatitis B/sangre , Hepatitis B/diagnóstico , Hepatitis B/virología , Humanos , Sensibilidad y Especificidad , Análisis de Secuencia de ADN , Carga Viral
10.
Cell Tissue Bank ; 8(4): 267-86, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17440834

RESUMEN

Organ and tissue transplant is now the treatment of choice for many end stage diseases. In the recent years, there has been an increasing demand for organs but not a similar increase in the supply leading to a severe shortage of organs for transplant resulted in increasing wait times for recipients. This has resulted in expanded donor criteria to include older donors and donors with mild disease. In spite of implementation of more stringent criteria for donor selection, there continues to be some risk of donor derived malignancy. Malignancy after transplantation can occur in three different ways: (a) de-novo occurrence, (b) recurrence of malignancy, and (c) donor-related malignancy. Donor related malignancy can be either due to direct transmission of tumor or due to tumor arising in cells of donor origin. We will review donor related malignancies following solid organ transplantation and hematopoeitic progenitor cell transplantation. Further, we will briefly review the methods for detection and management of these donor related malignancies.


Asunto(s)
Selección de Donante , Neoplasias/etiología , Trasplante de Órganos , Donantes de Tejidos , Humanos , Trasplante de Órganos/efectos adversos
11.
Transfusion ; 47(2): 194-200, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17302763

RESUMEN

BACKGROUND: Reports of human tissue allograft-transmitted infections have underscored the need for better accounting of allografts in health-care facilities. The Joint Commission on Accreditation of Healthcare Organizations (JCAHO) implemented new storage and issuance tissue standards for hospital oversight as of July 1, 2005. This study sought to survey hospital tissue responsibilities. STUDY DESIGN AND METHODS: The AABB Tissue Task Force conducted a Web-based survey distributed to all 904 hospital institutional members in January 2005. The survey asked about tissue type used, breadth of responsibility, hospital department involvement, and views on AABB involvement. Data from 402 of 904 (45%) respondents were tabulated and analyzed. RESULTS: Among the 402 respondents, 325 (81%) used allogeneic and/or autologous human tissue. The most frequently used tissues were musculoskeletal (n = 240, 74%) and skin (n = 169, 52%) allografts. The department of surgery (e.g., operating room; n = 245, 76%) most often had responsibility for tissue use, followed by the blood bank (i.e., transfusion service; n = 164, 51%); surgery most frequently had responsibility for all tissue types except peripheral blood progenitor cells. Only 32 of 402 (8%) respondents had plans for increased oversight in the next 12 months; 129 of 178 (72%) thought there was a role for AABB in developing guidance on hospital tissue responsibilities. CONCLUSIONS: In this survey, most AABB member hospital respondents indicated facility use of allogeneic and/or autologous tissues. Although tissue allograft responsibility by surgery was extensive, hospital blood banks also had significant involvement. Few blood banks, however, plan increased oversight in the near future. Given JCAHO standards, blood banks have an opportunity to assist their hospital in planning for assigned tissue responsibilities and oversight to ensure patient safety.


Asunto(s)
Bancos de Sangre/estadística & datos numéricos , Infección Hospitalaria/prevención & control , Hospitales/estadística & datos numéricos , Joint Commission on Accreditation of Healthcare Organizations , Bancos de Tejidos/estadística & datos numéricos , Bancos de Sangre/normas , Infección Hospitalaria/epidemiología , Adhesión a Directriz , Encuestas de Atención de la Salud/estadística & datos numéricos , Hospitales/normas , Humanos , Internet , Garantía de la Calidad de Atención de Salud , Bancos de Tejidos/normas , Trasplante Homólogo , Estados Unidos/epidemiología
12.
Transfus Apher Sci ; 36(1): 17-22, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17251060

RESUMEN

BACKGROUND: In December 2004, Pall Corporation initiated voluntary recall of certain filters used for leukocyte-reduction of blood products. Although our center had not used the implicated lots, certain customers reported observing increased hemolysis in the red-cell units (RC) provided by us. The purpose of this study was to determine the level of hemolysis seen in RC produced by our center. METHODS: In the first-phase, we evaluated 20 leukocyte-reduced (LR)-RC, those judged by one of our hospitals to have the highest degree of hemolysis (age: 10-30 days; average=16 days). Results were compared to ten randomly selected non-LR-RC (age: 10-19 days; average: 15 days). Samples obtained directly from the RC were tested for hemoglobin (Hb), hematocrit (Hct) and supernatant-Hb. Percent-hemolysis (% hemolysis) was calculated. In the second-phase, the above measurements were made on 70RCs. Ten RCs were studied before and after leukofilteration on day-2 after collection. Ten units each (LR & non-LR) were selected randomly from inventory at days: 15, 30 and 40 after collection (LR-units filtered within 48 h). RESULTS: In the first-phase LR-RCs exhibited an average 0.06% hemolysis vs. 0.02% for non-LR units. In the second-phase the average % hemolysis before and after filteration on day-2 (LR: 0.04% & non-LR: 0.04%) was similar. While on days: 15 (LR: 0.09%, non-LR: 0.05%) and 30 (LR: 0.16%, non-LR: 0.13%) % hemolysis was slightly more in LR as compared to non-LR. It was the opposite for day 40 (LR: 0.19%, non-LR: 0.31%). However, none of these differences were statistically significant. CONCLUSIONS: The % hemolysis increased as the age of the unit increased. There was no significant statistical difference between LR-RC and non-LR-RCs. This data did not confirm our hospitals' concerns regarding increased hemolysis following LR.


Asunto(s)
Transfusión de Eritrocitos , Eritrocitos , Hemólisis , Procedimientos de Reducción del Leucocitos , Preservación Biológica , Eritrocitos/citología , Femenino , Humanos , Masculino , Factores de Tiempo
13.
Cell Tissue Bank ; 8(3): 187-94, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17094018

RESUMEN

Despite improvements and recent attempts to standardize techniques to isolate islets from human donor pancreata, there still exists the problem of consistently recovering sufficient quantities of high quality islets. Moreover, achieving consistent recoveries of high numbers of good quality islets becomes even more challenging from marginal grade human donor pancreata with prolonged cold ischemic times. In this study, we investigate whether addition of Pefabloc SC, a serine protease inhibitor, in combination with Pulmozyme, a recombinant human DNase I, to Liberase HI improves islet isolation outcome from marginal grade human donor pancreata (cold ischemic time > 12 h). Twenty-three marginal grade human donor pancreata were randomly digested using four different enzyme preparations: (1) Liberase alone (n = 6), (2) +Pefabloc (n = 7), (3) +Pefabloc/Pulmozyme (n = 5), and (4) +Pulmozyme (n = 5). Overall, there were no significant differences in donor age, body mass index (BMI), pancreas weight, and cold ischemic time. After purification, significantly higher islet yields (3,281 +/- 590 IE/g) were obtained with the Pefabloc/Pulmozyme group as compared to the Liberase alone (1,615 +/- 305 IE/g) or the Pefabloc group (1,255 +/- 261 IE/g) (P < 0.05). Significant improvements in islet viability were also noted from the Pefabloc/Pulmozyme group (87.3 +/- 4.4%) as opposed to islets isolated from the Pefabloc group (75.2 +/- 3.9%) (P < 0.05). No significant differences in insulin secretory response to glucose stimulation among the four groups were observed, which indicates that the addition of Pefabloc and/or Pulmozyme does not have a detrimental effect on the functionality of islets. It is concluded that the addition of Pefabloc in combination with Pulmozyme to the Liberse HI significantly improves islet isolation outcome and potentially impacts the viability and morphology of the islets obtained from marginal grade human donor pancreata with prolonged cold ischemic times.


Asunto(s)
Separación Celular/métodos , Colagenasas/metabolismo , Desoxirribonucleasa I/metabolismo , Islotes Pancreáticos/metabolismo , Termolisina/metabolismo , Donantes de Tejidos , Adulto , Humanos , Insulina/metabolismo , Secreción de Insulina , Islotes Pancreáticos/citología , Islotes Pancreáticos/efectos de los fármacos , Persona de Mediana Edad , Sulfonas/farmacología
14.
Transfus Apher Sci ; 2006 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-17098475

RESUMEN

The Publisher regrets that this article was an accidental duplication of an article that has already been published in Transfus Apher Sci, 36 (1) 17 - 22, doi:10.1016/j.transci.2006.09.007. The duplicate article has therefore been withdrawn.

15.
Cell Tissue Bank ; 7(3): 195-201, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16933041

RESUMEN

BACKGROUND: Research grade pancreata preserved by the two-layer method (TLM) yield significantly greater numbers of islets than organs stored with University of Wisconsin solution (UW). The goal of this study was to determine whether this would hold true for pancreata that meet selection criteria for clinical grade organs. METHODS: Pancreata were chosen based upon a pre-defined set of criteria used for selecting clinical grade pancreata. Thirteen of these organs were preserved in UW and five pancreata were preserved by the TLM. Islets were isolated and evaluated according to the Edmonton protocol. RESULTS: The average preservation time was significantly longer for organ preserved with TLM (9.5 + 2.0 h) as compared to UW (5.8 + 0.6 h, p = 0.015). The pancreata of TLM group resulted in a significant increase in islet yields (3588 +/- 500 vs. 2536 +/- 312 IE/g pancreas, p<0.05). Visual scoring of islets indicated that islets were better from TLM group (8.3 +/- 0.3 vs. 7.3 +/- 0.2), and islet survival rates after culture were higher from organs stored with the TLM (87 +/- 17 vs. 55 +/- 7.4, p<0.05). Other parameters such as viability, insulin content, and stimulation index were similar between the two groups. All the preparations from the TLM group, but only 54% of preparations from the UW group, qualified for islet transplantation. The two recipients receiving islets from TLM group, daily insulin requirements were reduced and C-peptide levels were increased. CONCLUSION: Compared to storage with UW, exposure of pancreata to the TLM resulted in greater islet yields and improved quality of islets despite longer preservation period. Consequently, pancreata that meet clinical grade status should be preserved by the TLM prior to islet isolation.


Asunto(s)
Islotes Pancreáticos , Preservación de Órganos , Adenosina , Adulto , Alopurinol , Glutatión , Humanos , Insulina , Persona de Mediana Edad , Soluciones Preservantes de Órganos , Rafinosa
16.
Cell Tissue Bank ; 6(4): 255-62, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16308764

RESUMEN

Nucleic acid testing (NAT) has reduced the risk of transmitting infectious disease through blood transfusion. Currently NAT for HIV-1 and HCV are FDA licensed and performed by nearly all blood collection facilities, but HBV NAT is performed under an investigational study protocol. Residual risk estimates indicate that NAT could potentially reduce disease transmission through transplanted tissue. However, tissue donor samples obtained post-mortem have the potential to produce an invalid NAT result due to inhibition of amplification reactions by hemolysis and other factors. The studies reported here summarize the development of protocols to allow NAT of deceased donor samples with reduced rates of invalid results. Using these protocols, inventories from two tissue centers were tested with greater than 99% of samples producing a valid test result.


Asunto(s)
ADN Viral/sangre , ARN Viral/sangre , Donantes de Tejidos , Virosis/diagnóstico , Virosis/prevención & control , Recolección de Muestras de Sangre , VIH/genética , VIH/aislamiento & purificación , Hemoglobinas/análisis , Hemólisis , Hepacivirus/genética , Hepacivirus/aislamiento & purificación , Humanos , Técnicas de Amplificación de Ácido Nucleico , Plasma/virología , Sensibilidad y Especificidad , Factores de Tiempo , Virosis/transmisión , Virosis/virología
18.
J Endocrinol ; 185(3): 445-55, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15930171

RESUMEN

In this study, we investigated the use of a novel oxygen biosensor system to detect changes in oxygen consumption rates (OCRs) by islets in response to glucose. Islets from non-human primate and human pancreata were seeded into an oxygen biosensor system microplate and exposed to basal (2.8 or 5.6 mM) or high (16.7 or 33.3 mM) glucose over either a long-term or a short-term culture. Our data clearly demonstrated that non-human primate islets cultured in high glucose conditions exhibited significant increases in OCRs over a 168 h extended culture period (P<0.05), which indicates an accelerated rate of beta-cell metabolism triggered by glucose over time. Significant increases in OCRs (P<0.01) were also attained in both non-human primate and human islets exposed to high glucose conditions in a 120 min short-term incubation period. OCRs exhibited by human islets exposed to different glucose concentrations correlated with insulin secretion (r(2)=0.7681, P<0.01). Moreover, the OCR stimulation index (i.e. OCR at high glucose/OCR at basal glucose) was significantly greater in human islets displaying high viabilities as opposed to islets exhibiting low viabilities (P<0.05). Together these data demonstrate that this novel oxygen biosensor system documents significant increases in islet oxygen consumption upon acute and chronic exposure to high glucose concentrations. Importantly, this methodology rapidly and robustly detects changes in OCRs by islets in response to high glucose stimulation that correlate well with the metabolic activities and functional viability of islets and clearly delineates significant differences in OCR stimulation index between high and low viability human islets, and therefore may prove to be an effective approach for quickly assessing the functional viability of islets prior to transplantation.


Asunto(s)
Glucosa/farmacología , Islotes Pancreáticos/metabolismo , Consumo de Oxígeno , Animales , Técnicas Biosensibles , Técnicas de Cultivo de Célula , Supervivencia Celular , Humanos , Insulina/metabolismo , Secreción de Insulina , Islotes Pancreáticos/citología , Trasplante de Islotes Pancreáticos , Macaca nemestrina , Estimulación Química , Factores de Tiempo
19.
Transfusion ; 45(2): 254-64, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15660836

RESUMEN

BACKGROUND: Estimates for human immunodeficiency virus (HIV)-1 and hepatitis C virus (HCV) transfusion-transmitted risks have relied on incidence derived from repeat donor histories and imprecise estimates for infectious, preseroconversion window periods (WPs). STUDY DESIGN AND METHODS: By use of novel approaches, WPs were estimated by back-extrapolation of acute viral replication dynamics. Incidence was derived from the yield of viremic, antibody-negative donations detected by routine minipool nucleic acid testing (MP-NAT) of 37 million US donations (1999-2002) or from sensitive/less-sensitive HIV-1 enzyme immunoassay (S/LS-EIA) results for seropositive samples from 6.5 million donations (1999). Incidences and WPs were combined to calculate risks and project yield of individual donation (ID)-NAT. RESULTS: The HIV-1 WP from presumed infectivity (1 copy/20 mL) to ID-NAT detection was estimated at 5.6 days, and the periods from ID to MP-NAT detection and from MP-NAT to p24 detection at 3.4 and 6.0 days, respectively; corresponding estimates for HCV were 4.9, 2.5, and 50.9 days (the latter represents period from MP-NAT to HCV antibody detection). The HIV-1 incidence projected from MP-NAT yield or from S/LS-EIA data was 1.8 per 100,000 person-years, resulting in a corresponding HIV-1 transfusion-transmitted risk of 1 in 2.3 million. The HCV incidence from MP-NAT yield was 2.70 per 100,000 person-years with a corresponding risk of 1 in 1.8 million donations. Conversion from MP-NAT to ID-NAT was projected to detect two to three additional HIV-1 and HCV infectious units annually. CONCLUSIONS: MP-NAT yield and S/LS-EIA rates can accurately project transfusion risks. HCV and HIV-1 risks, currently estimated at 1 per 2 million units, could be reduced to 1 in 3 to 4 million units by ID-NAT screening.


Asunto(s)
Transfusión Sanguínea/estadística & datos numéricos , Infecciones por VIH/epidemiología , Infecciones por VIH/transmisión , VIH-1 , Reacción a la Transfusión , Enfermedad Aguda , Donantes de Sangre/estadística & datos numéricos , Infecciones por VIH/prevención & control , Humanos , Incidencia , Valor Predictivo de las Pruebas , Factores de Riesgo
20.
Transplantation ; 78(6): 839-43, 2004 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-15385802

RESUMEN

BACKGROUND: Islet transplantation is on the rise for the treatment of type 1 diabetes. Apparent donor shortages could be alleviated through use of living donor pancreata. A critical issue for using a section of pancreas from living donors is whether islet yields would be sufficient for transplantation. METHODS: After obtaining human pancreata, islets were isolated from the head section (n=20, head group), tail section (n=23, tail group) or whole pancreas (n=24, whole group). Islets were isolated by enzymatic digestion followed by purification, then assessed for yields, purity, morphology, functionality, and insulin content. RESULTS: Fifteen of twenty cases (75%) in the head group, all cases (100%) in the tail group, and 23 of 24 cases (96%) in the whole group were successfully completed for islet isolation. Islet yield per gram pancreas was significantly higher in the tail group compared with both the head and whole groups (head, 1,472+/-326 IE/g; tail, 4,256+/-574 IE/g; whole, 2,424+/-506 IE/g). Total islet yield from the head group was significantly lower compared with both tail and whole groups (head, 75,016+/-18,933 IE; tail, 197,469+/-28,236 IE; whole, 208,207+/-43,414 IE), and the tail group showed similar islet yield to the whole group. The whole group showed significantly lower purities and the head group showed significantly lower morphologic scores. There were no significant differences in viability, function, and insulin content among the three groups. CONCLUSIONS: The tail section of the human pancreas is suitable for islet isolation. The living donor islet transplantation may be feasible using only this section of the pancreas for the first transplantation to reduce hypoglycemic unawareness for small recipients, which might be followed by the second islet transplantation from cadaveric donor.


Asunto(s)
Trasplante de Islotes Pancreáticos/métodos , Islotes Pancreáticos/citología , Donadores Vivos , Páncreas/anatomía & histología , Recolección de Tejidos y Órganos/métodos , Adulto , Separación Celular/métodos , Supervivencia Celular , Humanos , Islotes Pancreáticos/fisiología , Persona de Mediana Edad , Tamaño de los Órganos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...