Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019163 (hepatitis B)
 38,309 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In common with other developed countries, the United States has placed a great deal of emphasis on blood safety. As a result of careful donor selection and the use of advanced tests, including nucleic acid testing (NAT), the risk of transmission of human immunodeficiency virus and hepatitis C virus has been reduced to about 1 in 1.5 million donations. NAT for hepatitis B virus has not been introduced, but nevertheless the risk is low. Attention recently has been focused on emerging infections. NAT for West Nile virus was implemented within 6 to 8 months of recognition of the need to prevent transfusion transmission of this newly introduced virus. Approximately 1000 potentially infectious donations were identified and removed from the blood supply during the 2003 season. Other emerging infections attracting attention include Chagas' disease, babesiosis, malaria, and variant Creutzfeldt-Jakob disease.
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PMID:Current safety of the blood supply in the United States. 1561 52

Blood transfusion provides an ideal portal of entry for microorganisms. Although current residual risks of microbial infection by transfusion are extremely low in the developed world, the requirements for even safer blood are paradoxically increasing. Such requirements are partly a legacy of the tragic transmissions of human immunodeficiency virus (HIV) by blood early in the acquired immunodeficiency syndrome pandemic and are legally expressed in consumer protection laws imposing strict product liability. Enhanced safety is called for, not only for recognized agents (especially bacteria, which cause most current transfusion-transmissible infections [TTIs]and have only recently been addressed) but also for potential future "emerging" TTIs. These possibilities are not merely theoretical. TTIs of HIV-1, HIV-2, hepatitis B virus vaccine escape mutants, human herpesvirus 8, West Nile fever virus, and variant Creutzfeld-Jakob disease amply demonstrate the continual emergence of such threats. For recognized agents, the possibilities of test errors, misreporting, process-control failures, and false-negative results (although rare with modern automation) remain. In principle, an all-embracing, pan-effective microbe-inactivation procedure offers a potential solution to blood safety concerns. Such procedures may also allow the removal of several existing antimicrobial interventions. However, blood services remain to be convinced that the various prerequisites for safe and effective pathogen inactivation have been met. Not the least of these prerequisites is that all blood components can be inactivated to provide a single streamlined alternative blood safety strategy. Furthermore, the huge potential value of effective pathogen-inactivation systems for developing countries should not be forgotten once such systems are perfected.
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PMID:The rationale for pathogen-inactivation treatment of blood components. 1561 54

Two main types of safety procedures must be applied to biological products, including plasma derivatives: (i) preventive procedures and (ii) elimination procedures. Prevention includes epidemiological control of donor populations; checks on each donor's health condition; analysis of each donation for the main pathogens using serological methods; additional analysis of all plasma for human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis A virus (HAV) and the B19 virus, using nucleic acid amplification techniques (NAT). A 60 days or longer inventory hold of all plasma donations is applied, to allow additional time to discard previous donations from potential seroconverting or otherwise rejectable donors. Elimination procedures minimize the low residual risk of transmitting pathogens, including unknown or previously undetected ones. Since the introduction 20 years ago of solvent-detergent treatment, very effective against enveloped viruses (HIV, HBV, HCV, West Nile virus, SARS, avian influenza virus etc), there have been no known cases of transmission of this type of pathogens by products manufactured according to this procedure. Other inactivation procedures such as pasteurization, dry-heat or nanofiltration may prove equally effective. In addition, dry-heat treatment and nanofiltration are capable of effectively eliminating non-enveloped viruses (HAV, B19 virus). Recent studies show that the B19 virus is much more sensitive to heat (in lyophilized state or by pasteurization) and acid pH than previously thought. Although there is no evidence for the transmission of classic transmissible spongiform encephalopathies (TSEs) through blood or blood-products transfusion, four possible cases have been reported in the United Kingdom involving transmission by non-leukoreduced blood components of the agent that causes variant Creutzfeldt-Jakob Disease (vCJD), a disease linked to the outbreak of bovine spongiform encephalopathy (BSE) which took place in that country. However, there are no cases of human TSE (classic or variant) transmission by plasma-derived products. Analytical methods capable of detecting the vCJD agent in patients' brains (where high titres are found) and other tissues (such as the spleen, appendix and lymph nodes, where much lower concentrations are found) are unable to detect the agent in blood or plasma from patients with vCJD, even in the clinical phase of the disease. Experiments by Grifols and other groups show that the capacity of the production processes to eliminate vCJD agent models is many orders of magnitude greater than the maximum expected load of the agent. In this regard, the efficacy of precipitation, affinity chromatography, depth filtration and nanofiltration are particularly notable.
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PMID:Safety procedures of coagulation factors. 1807 96

A spectrum of blood-borne infectious agents is transmitted through transfusion of infected blood donated by apparently healthy and asymptomatic blood donors. The diversity of infectious agents includes hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency viruses (HIV-1/2), human T-cell lymphotropic viruses (HTLV-I/II), Cytomegalovirus (CMV), Parvovirus B19, West Nile Virus (WNV), Dengue virus, trypanosomiasis, malaria, and variant CJD. Several strategies are implemented to reduce the risk of transmitting these infectious agents by donor exclusion for clinical history of risk factors, screening for the serological markers of infections, and nucleic acid testing (NAT) by viral gene amplification for direct and sensitive detection of the known infectious agents. Consequently, transfusions are safer now than ever before and we have learnt how to mitigate risks of emerging infectious diseases such as West Nile, Chikungunya, and Dengue viruses.
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PMID:Transfusion-transmitted infectious diseases. 1923 Dec 36

Corneal transplantation safety is widely dependent on clinical donor selection. Donor-to-host transmission of rabies and Creutzfeldt-Jakob disease is well established, and it is lethal for the recipient. Taking into consideration this latter figure, contraindications to ocular tissue transplantation include not only rabies, contact with rabies virus, spongiform encephalitis, family history of spongiform encephalitis, recipients of human pituitary-derived hormones before 1987, surgery using dura mater and brain/spinal surgery before 1992, but also CNS diseases of unknown etiology or those with unknown risk of transmission. It has been established that hepatitis B virus and herpes simplex virus can be transmitted by corneal transplantation, and both diseases are contraindications to transplantation. HIV infection, syphilis, hepatitis C, hepatitis A, tuberculosis, HTLV-1 and -2 infection, active leprosy, active typhoid, smallpox and active malaria are also contraindications to ocular tissue transplantation even if no evidence of donor-to-recipient transmission has been demonstrated. A history of corneal refractive surgery in the donor eye, ocular inflammation, retinoblastoma, and malignant tumors of the anterior segment are contraindications to keratoplasty.
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PMID:Donor selection, retrieval and preparation of donor tissue. Donor selection. 1949 34

The first remarkable adverse drug reaction (ADR) reported in Japan was anaphylactic shock caused by penicillin. Although intradermal testing for antibiotics had been exercised as prediction method of anaphylactic shock for a long time, it was discontinued in 2004 because of no evidence for prediction. The malformation of limbs, etc. caused by thalidomide was a global problem, and thalidomide was withdrawn from the market. Teratogenicity testing during new drug development has been implemented since 1963. Chinoform (clioquinol)-iron chelate was detected from green tongue and green urine in patients with subacute myelo-optic neuropathy (SMON) and identified as a causal material of SMON in 1970. Chinoform was withdrawn from the market, and a fund for relief the health damage caused by ADR was established in 1979. The co-administration of sorivudine and fluorouracil anticancer agents induced fatal agranulocytosis, and sorivudine was withdrawn from the market after being on sale for one month in 1993. The guidelines for package inserts were corrected with this opportunity, and early phase pharmacovigilance of new drugs was introduced later. Since acquired immune deficiency syndrome, and hepatitis B and C were driven by virus-infected blood products, the Ministry of Health, Labor and Welfare tightened regulations regarding biological products in 2003, and a fund for relief of health damage caused by infections driven from biological products was established in 2004. The other remarkable ADRs were quadriceps contracture induced by the repeated administration of muscular injection products and Creutzfeldt-Jakob disease caused by the transplantation of human dry cranial dura matter, etc. The significance of safety measures for drugs based on experiences related to ADRs is worthy of notice. New drugs are approved based on a benefit-risk assessment, if the expected therapeutic benefits outweigh the possible risks associated with treatment. Since unexpected, rare and serious ADRs have been detected after administration to many patients in the post-marketing stage, risk management is required for product life-cycle management.
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PMID:[The history of adverse drug reactions, relief for these health damage and safety measures in Japan]. 2052 11

Transfusion safety relating to blood-transmissible agents is a major public health concern, particularly when faced with the continuing emergence of new infectious agents. These include new viruses appearing alongside other known reemerging viruses (West Nile virus, Chikungunya) as well as new strains of bacteria and parasites (Plasmodium falciparum, Trypanosoma cruzi) and finally pathologic prion protein (variant Creutzfeldt-Jakob disease). Genomic mutations of known viruses (hepatitis B virus, hepatitis C virus, human immunodeficiency virus) can also be at the origin of variants susceptible to escaping detection by diagnostic tests. New technologies that would allow the simultaneous detection of several blood-transmissible agents are now needed for the development and improvement of screening strategies. DNA microarrays have been developed for use in immunohematology laboratories for blood group genotyping. Their application in the detection of infectious agents, however, has been hindered by additional technological hurdles. For instance, the variability among and within genomes of interest complicate target amplification and multiplex analysis. Advances in biosensor technologies based on alternative detection strategies have offered new perspectives on pathogen detection; however, whether they are adaptable to diagnostic applications testing biologic fluids is under debate. Elsewhere, current nanotechnologies now offer new tools to improve the sample preparation, target capture, and detection steps. Second-generation devices combining micro- and nanotechnologies have brought us one step closer to the potential development of innovative and multiplexed approaches applicable to the screening of blood for transmissible agents.
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PMID:Detection of blood-transmissible agents: can screening be miniaturized? 2054 2

Conversion to a single-donor (apheresis) platelet inventory in Western Europe and other countries that provide similar health care to the US but rely on buffy-coat pooled whole-blood-derived platelets will confer the benefit of a > or = 2-fold reduction in the risk of all emerging transfusion-transmitted infections (TTIs). In Europe, this benefit will include a > or = 2-fold reduction in the risk of acquiring variant Creutzfeldt-Jakob disease (vCJD) from platelet transfusion. In countries that use buffy coats from first-time donors to produce platelet pools, there will also be a > or = 2-fold reduction in the risk of human immunodeficiency virus, hepatitis B virus, and hepatitis C virus infections. Conversion to a single-donor inventory collected from male donors (or female donors without a history of pregnancy or shown not to have white-blood-cell antibodies) should also reduce the risk of transfusion-related acute lung injury, although this prediction is based on theory and may not materialize or prove hard to document. Because conversion to a single-donor inventory can effect a > or = 2-fold reduction in the risk of all TTIs without incurring any risk, it is a more advantageous risk-reduction strategy for emerging TTIs compared with the introduction of pathogen-reduction systems for platelets. The latter cannot protect from vCJD and potentially also from some other emerging TTIs; moreover, they have recently been associated with an increased risk of bleeding.
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PMID:The relative safety of pooled whole-blood-derived platelets prepared by the buffy-coat method versus single-donor (apheresis) platelets. 2085 91

During the last 20 years, the safety of blood products increased dramatically with regard to the infectious risk and notably to that represented by retroviruses (HIV and HTLV) and hepatitis B and C viruses. The aim of this review is to identify the residual and emergent viral threats that could be responsible for the occurring of new contaminations in the receivers of blood products. Beside many other viruses (HHV-8, erythrovirus B19, hepatitis A and E viruses...), a special attention has been paid to emerging arbovirus diseases (West Nile virus infection, dengue, chikungunya) that threaten to occur in the French metropolitan area following the implantation in Europe of the mosquito Aedes albopictus, the main vector of dengue and chikungunya in temperate regions. Another blood-linked risk, notably in United Kingdom and France, is the prion agent responsible for the variant form of the Creutzfeldt-Jakob disease. The review is concluded by a brief overview of the measures aimed to control these emergences, including the exclusion of at-risk donors, the diagnostic tests able to detect a specific agent, the leukocyte reduction of labile blood products, and the physical or chemical treatments aiming the nonspecific inactivation of infectious agents potentially present in blood without impairing significantly the physiological properties of blood compounds. The ability to control prospectively the new viral risks linked to blood products is a challenge for the preservation of the confidence of both clinicians and receivers in the safety of blood transfusion.
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PMID:[Emergent viral threats in blood transfusion]. 2141 28

Millions of patients in the UK benefit from the use of both plasma derivatives and blood components that are seen as critical interventions in current medicine. Measures are in place to significantly reduce the risks associated with blood transfusion and plasma derivatives; however, these measures themselves are not risk free. Over the past 20 years, advances in technology and regulation have seen major reductions in the risks associated with transfusion. International blood services, industry, and regulators strive to maintain safety levels through constant monitoring, assessment, and response to changing risk factors. Regulation of screening tests together with the development and introduction of nucleic acid technique tests for hepatitis B virus, hepatitis C virus, and human immunodeficiency virus has improved blood safety. However, other risks, including the changing epidemiology of transfusion-transmitted infections, bacterial contamination of platelets, incorrect blood component transfusion, and variant Creutzfeldt-Jakob disease, require further attention. Risks such as these are often complex, and there is a difficult balance to be struck between donors/recipients' benefit and adequacy of blood supply. The introduction of any new safety measure therefore requires robust, evidence-based evaluation of associated benefit, both clinical and economical. This review presents a UK perspective on how the safety of the blood supply is maintained in the face of uncertain risks.
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PMID:The management of blood safety in the presence of uncertain risk: a United kingdom perspective. 2212 10


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