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Biomedical subjects

J A van der Does

Publications and source records attributed to J A van der Does.

17 recordsLinked to original sources
PubMed2000

Evaluation of automated nucleic acid extraction devices for application in HCV NAT.

BACKGROUND: To further improve the safety of the blood supply, various national blood transfusion organizations presently use or are in the process of implementing routine HCV NAT in minipools. According to the Committee for Proprietary Medicinal Products (CPMP) of the European Union, the HCV NAT detection limit of the assay should be 100 IU per mL (270 geq/mL) for testing initial plasma pools. Paul Ehrlich Institute (PEI) regulations stipulate that 5000 IU per mL (13,500 geq/mL) must be detected to calculate the amount contributed by individual donations composing the minipool. The sensitivity for HCV RNA extraction achieved by three commercially available laboratory kits was compared. STUDY DESIGN AND METHODS: Nucleic acids from 1-in-3 serial dilutions of an HCV RNA run control (Pelispy, CLB) were extracted with three kits (Cobas Amplicor, Roche Diagnostic Systems; BioRobot 9604, Qiagen; and NucliSens Extractor, Organon Teknika). HCV PCR of all extracts was performed using a second-generation Cobas Amplicor HCV test and the Cobas Amplicor analyzer. RESULTS: The manual Cobas Amplicor, the BioRobot 9604, and the NucliSens Extractor setups allow a 95-percent HCV RNA detection limit of 129, 82, and 12 geq per mL, respectively. The maximal pool size for the manual Cobas Amplicor, the BioRobot 9604, and the NucliSens Extractor kits that would still meet the PEI criteria for HCV NAT in minipools was calculated at 104, 164, and 1125 donations, respectively. CONCLUSION: All three HCV NAT kits evaluated meet the criteria set by CPMP and PEI. The highest sensitivity for HCV NAT screening can be achieved with the high-volume NucliSens Extractor method in combination with the Cobas Amplicor HCV v2.0 test on the Cobas Amplicor analyzer.

Blood Donors↗
PubMed1996

Effects of chronic factor VIII substitution on immune parameters in HIV seronegative haemophiliacs: a comparison between cryoprecipitate and factor VIII concentrate.

Chronic substitution therapy of HIV-negative haemophiliacs with factor VIII products can result in abnormalities of ex-vivo measured immune parameters. To assess a possible relation between these abnormalities and product purity, we analyzed two groups of HIV-negative HCV-positive haemophiliacs, one treated with cryoprecipitate exclusively, the other with more purified factor VIII concentrates. Compared to age matched non-transfused male controls, increased numbers of white cells, granulocytes, IgG and IgM levels and decreased CD4+/CD8+ ratios were found in both patient groups. In the concentrate receivers, the numbers of mononuclear cells, CD4+, CD8+ and CD3+/HLA-DR+ cells indicating activated T-cells, were higher than in the cryoprecipitate group. In conclusion, both cryoprecipitate and intermediate/high purity concentrate recipients showed immune parameter abnormalities. These abnormalities tended to be somewhat more pronounced in patients treated with concentrates. By now there is no indication of the clinical relevance of the abnormalities in previously treated HIV seronegative haemophiliacs.

Adolescent↗
PubMed1986

Evaluation of six enzyme immunoassays for antibody against human immunodeficiency virus.

Six commercial enzyme immunoassays (EIA) were evaluated in 6488 serum samples, with immunoblot analysis as the confirmatory test for antibodies against human immunodeficiency virus (HIV). The Abbott and Wellcome tests identified all 163 immunoblot-positive samples correctly, whereas the other tests did not detect 1-3 samples. In AIDS patients (predominantly with antibodies to gp41env) Organon's EIA was less sensitive (p less than 0.05) and Wellcome's more sensitive (p less than 0.05) than the immunoblot assay. In symptom-free anti-HIV-positive subjects (antibodies to almost all viral antigens and high titres of anti-p24gag) all the EIA were significantly (p less than 0.05) less sensitive than the immunoblot assay. The frequencies of false-positive reactions in a "tricky" panel of samples from patients with autoimmune and acute viral diseases and in a blood-donor panel were Abbott 9.5%, 0.42%: Organon 1.7%, 0%; Litton 1.0%, 0.4%; Behring 2.7%, 0.06%; Wellcome 0%, 0%; and Pasteur 0%, 0.02%. The results of a seventh EIA (Dupont) were excluded from the study at the company's request. All six EIA evaluated are suitable tests for anti-HIV screening in samples from patients and blood donors.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Influence of the primary anticoagulant on the recovery of factor VIII in cryoprecipitate.

The influence of anticoagulant on overall factor VIII-yield was measured by drawing blood from one donor simultaneously in three bags containing ACD, CPD and heparin, respectively. After parallel processing factor VIII:C and factor VIII:CAg were measured. It is concluded that, under the circumstances used in this experiment, CPD gives the highest yield of factor VIII.

Adenine↗
PubMed1986

Starting a plasmapheresis program with hollow-fiber filtration.

In a routine donor center, a program of hollow-fiber filtration can be instituted. With the Organon Teknika PLASMAPUR system the collection of 600 ml plasma was completed within 50 min in 76% of the procedures. Changing the tubing set took 12-15 min. From the plasma a frozen cryoprecipitate is made with a recovery of 59%. After pooling, lyophilization and heat treatment, the recovery is 42%.

Allied Health Personnel↗
PubMed1977

Haemodynamic side effects of antilymphocyte serum.

Haemodynamic side effects of antilymphocyte serum (ALS) have been studied in six dogs treated with equine anti-dog ALS. All animals responded with a severe but transient reduction of cardiac output and, in most cases, a drop in aortic pressure. This effect is best explained by a direct negative inotropic action followed by secondary vasoconstriction. An indirect effect of ALS by release of cardiotoxic substances from damaged blood cells seems to be a more probable explanation than a direct action of ALS on cardiac cell membranes.

Animals↗
PubMed1973

Consequent intrafamilial immunization for DL-A haplotyping in canines.

A procedure of intrafamilial immunization is described for production of antisera recognizing DL-A haplotypes. In a colony consisting of 1 sire, 6 bitches, and 67 offspring all haplotypes could be accurately allocated. In the colony the observed reaction frequencies of the antisera are in agreement with mendelian codominant inheritance. Mixed lymphocyte culture tests confirmed the accuracy of the serologic typing and the presence of homozygous individuals within the colony. Further evidence is presented supporting the presence of two or more subloci within the DL-A system. Colonies of canines such as the one described should provide a sensitive system for evaluating interaction between serologic DL-A typing, MLC reactivity, and immune response genetics in a nonrodent species which is not highly inbred.

Animals↗