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Biomedical subjects

H W Reesink

Publications and source records attributed to H W Reesink.

At least 163 records · Page 9Linked to original sources
PubMed1988

Evaluation of three second-generation and three confirmatory assays for antibodies to human immunodeficiency virus.

The second-generation enzyme immunoassays (EIAs) for antibodies against human immunodeficiency virus (HIV) from three manufacturers (Abbott, Organon, Wellcome) and three anti-HIV confirmatory tests, i.e. Western Blot (WB, Biotech, Dupont), radioimmunoprecipitation assay (RIPA, CLB) and a competitive immunoassay (CIA, Abbott) were evaluated on a panel of 6,488 serum samples, which had previously been used for the comparison of seven first-generation EIAs. For the present study the panel was expanded with sequential serum samples from 12 individuals followed at 1- to 3-month intervals during seroconversion for anti-HIV. The second-generation EIAs and confirmatory tests were significantly more sensitive than the first-generation EIAs as was demonstrated by detection of 10- to 100-fold higher endpoint titers in anti-HIV-positive sera as well as by earlier detection of anti-HIV in 7-11 of the 12 subjects, who seroconverted. In all sera obtained during early HIV infection anti-gp 160/120env antibodies (WB, CIA) were found in addition to anti-p24 (WB, RIPA) and in serial twofold dilutions of these 'seroconversion samples' the new Abbott EIA and RIPA were significantly more sensitive than WB (p less than 0.05), whereas CIA and the new Organon EIA were significantly less sensitive than WB (p less than 0.05). The new Wellcome EIA was not statistically less sensitive than WB. The CIA was as sensitive as WB for antibodies to envelope proteins (gp41, gp160, gp120), but considerably less sensitive for core (p24) antibodies, as was shown in sera obtained during early as well as later clinical stages of HIV infection.(ABSTRACT TRUNCATED AT 250 WORDS)

Acquired Immunodeficiency Syndrome↗
PubMed1988

Preparation of leukocyte-poor platelet concentrates from buffy coats. III. Effect of leukocyte contamination on storage conditions.

To study the influence of contaminating leukocytes on the storage conditions of platelet concentrates (PC), various amounts of leukocytes were added to identical PC. From 12 blood donations, 12 leukocyte-poor PC were prepared and pooled. Subsequently, the pool was divided into 12 identical PC. The plasma volume of the PC was 58.6 +/- 0.6 ml, the platelet concentration was 1.01 +/- 0.04 x 10(9)/ml (mean +/- SD) and the red cell contamination did not exceed 10(7) per PC. To 4 groups of 3 PC, pooled leukocytes were added from the same 12 blood donations. The leukocyte contamination for each group of 3 PC was 0.14 +/- 0.05, 1.96 +/- 0.09, 5.53 +/- 0.98 and 13.0 +/- 0.93 x 10(6)/ml (mean +/- SD) for groups I-IV, respectively. The PC were stored for 7 days at 22 degrees C in normal polyvinylchloride bags. A significant correlation was found between increasing concentrations of leukocytes in the PC and the drop in pH (r = -0.93), glucose consumption (r = -0.91), lactic acid production (r = 0.93) and release of lactate dehydrogenase (r = 0.92) during storage of the PC. The excretion of beta-thromboglobulin, depletion of platelet adenine nucleotides, decreased ability to incorporate 3H-adenosine into metabolic nucleotides and poor morphology of the platelets were also significantly correlated with an increased number of leukocytes in the PC. These data show that high concentrations of leukocytes in PC have a significant detrimental effect on the viability of platelets during storage at 22 degrees C. We conclude that for good storage conditions of PC, the upper limit of leukocytes per PC should not exceed 10(7).

Blood Platelets↗
PubMed1988

Preparation of leucocyte-poor platelet concentrates from buffy coats. IV. Clinical evaluation.

To study survival and function of leukocyte-poor platelet concentrates (lp-PC) prepared from buffy coats, random platelet transfusions requested for thrombocytopenic patients were evaluated. The lp-PC issued were stored at 22 degrees C for either 1, 3 or 5 days before transfusion. From 31 transfusions, posttransfusion corrected count increments (CCI), corrected for body surface (m2) and divided by number of platelets transfused (1011), were calculated. The mean +/- SEM of the 1-, 24- and 48- hour CCI was 12.2 +/- 0.45, 11.2 +/- 0.51 and 8.8 +/- 0.58, respectively. No significant differences in CCI 24 h after transfusion were observed for 1p-PC stored for 1, 3 or 5 days. Hemostatic activity was observed in all 9 evaluable patients. It is concluded that platelets from 1p-PC survive well in patients, regardless of storage for 1, 3 or 5 days and that the platelets are hemostatically active after transfusion.

Blood Preservation↗
PubMed1987

Inactivation of 10(15) chimpanzee-infectious doses of hepatitis B virus during preparation of a heat-inactivated hepatitis B vaccine.

The safety of a plasma-derived hepatitis-B vaccine inactivated by two heating steps (90 sec at 103 degrees C followed by 10 hr pasteurization at 65 degrees C) was validated in chimpanzees; 10(3) chimpanzee-infectious doses (CID50) of hepatitis-B virus (HBV), subjected to the purification steps during production of the vaccine, were noninfectious in two chimpanzees. Furthermore, 10(6) CID50 of HBV heated at 103 degrees C for 90 sec and another 10(6) CID50 of HBV heated at 65 degrees C for 10 hr, were also not infectious in two other chimpanzees. All animals developed hepatitis-B infection after subsequent challenge with the untreated starting material, before the respective purification and inactivation procedures. Thus, the total reduction of infectivity of HBV during production of this vaccine was established to be at least 10(15) CID50.

Animals↗
PubMed1987

Inactivation of 12 viruses by heating steps applied during manufacture of a hepatitis B vaccine.

The efficacy of two heating cycles (90 sec at 103 degrees C and 10 hr at 65 degrees C) used during manufacture of a plasma-derived hepatitis-B vaccine was validated for the inactivation of 12 virus families. A period of 15 min warming up to 65 degrees C had already completely inactivated representatives of nine virus families, ie, poxvirus (vaccinia), picornavirus (encephalomyocarditis virus), togavirus (sindbis virus), coronavirus (mouse hepatitis virus), orthomyxovirus (influenza virus), rhabdovirus (vesicular stomatitis virus), herpes virus (cytomegalovirus), lentivirus (human immunodeficiency virus), and retrovirus (murine leukemia virus). After prolonged heating at 65 degrees C or heating for 90 sec at 103 degrees C, parvovirus (canine parvovirus) and the phage phiX174 were also completely inactivated. Papovavirus represented by simian virus 40 (SV-40) was the most heat-resistant virus evaluated. The infectivity of SV-40 was reduced by 10(4) Tissue Culture Infectious Doses (TCID50) per ml after 90 sec at 103 degrees C, but a marginal residual activity (less than 1.5 TCID50 per ml) was observed. Subsequent pasteurization for 10 h at 65 degrees C did not further reduce the infectivity of SV-40. This study shows that the two heat-inactivation steps used during the production of this vaccine kill a wide variety of viruses that might be present in human blood.

Bacteriophage phi X 174↗
PubMed1987

Survival in vivo of platelets stored for 48 hours in the buffycoat at 4 degrees C compared to platelet rich plasma stored at 22 degrees C.

High speed centrifugation allows separation of whole blood into cell free plasma, a buffy coat and leukocyte poor red cells. The buffy coat can be used for the preparation of platelet concentrates. High lactate production at 22 degrees C requires storage of the buffy coat at 4 degrees C. Survival in vivo of platelet concentrates prepared from buffy coats stored at 4 degrees C for 48 h (BC-PC) was compared with the survival in vivo of platelet concentrates from platelet rich plasma stored at 22 degrees C for 48 h (PRP-PC). Both methods were studied in the same healthy volunteers (n = 8) using 51Cr labeled autologous platelets. The mean +/- SD recovery 15 min after reinfusion of the BC-PC was 30.5% +/- 13.3% and for PRP-PC 41.4% +/- 7.9% (p less than 0.0001). The survival in vivo for BC-PC was 2.4 days +/- 0.4 days and for PRP-PC 7.0 days +/- 1.4 days (p less than 0.0001). Since the survival in vivo is significantly less for platelets derived from the buffy coat stored at 4 degrees C, we advocate storage of platelets at 22 degrees C.

Adult↗
PubMed1987

Preparation of leukocyte-poor platelet concentrates from buffy coats. I. Special inserts for centrifuge cups.

A special insert was developed for centrifuge cups in order to prepare leukocyte-poor platelet concentrates from buffy coats by using quadruple citrate phosphate dextrose-saline adenine glucose mannitol systems from different manufacturers. Each centrifuge cup could contain up to 4 sets of double bags allowing the preparation of 24 platelet concentrates per run. Optimal conditions for centrifugation of the buffy coats in the inserts were found to be 6 min at 380 g (2,150 g min). A platelet count of 69 +/- 19 X 10(9) and a leukocyte contamination of 14 +/- 10.5 X 10(6) per platelet concentrate was thereby obtained in a plasma volume of 63 +/- 10.5 ml (mean +/- SD). The method described allows large scale production of leukocyte-poor platelet concentrates from buffy coats in a closed system.

Blood Platelets↗
PubMed1987

Preparation of leukocyte-poor platelet concentrates from buffy coats. II. Lack of effect on storage of different plastics.

Six citrate phosphate dextrose (CPD)-saline adenine glucose mannitol (SAG M) quadruple systems were evaluated for the preparation and storage of leukocyte-poor platelet concentrates (PC) from buffy coats. The platelet storage bags examined were manufactured from normal polyvinylchloride (PVC) or special-type plastics. Biotest supplied PVC 76 (n = 14) and PVC 763 (n = 16) NPBI supplied PSV 3277 (n = 15) and DPL-110 (n = 14) and Terumo supplied Teruflex (n = 18) and molded Teruflex (n = 14). The PC were stored for 7 days at 22 degrees C on a horizontally shaking platform. Cell counts, pH, PO2, PCO2, morphology score and swirling patterns were monitored at 5, 72, 120 and 168 h. The plasma volumes averaged 63 ml and ranged from 39 to 81 ml, the overall mean +/- SD platelet concentration was 0.89 +/- 0.33 X 10(9)/ml. None of the PC had a leukoyte count higher than 10 X 10(6) per unit. After storage for 168 h, the pH ranged from 6.56 to 7.40 for all brands. The PO2 remained stable and even rose significantly (p less than 0.05) during storage in the NPBI PSV 3277 and Terumo molded Teruflex bags. The PCO2 decreased equally in all bags. Morphology scores were well maintained in 98% of all PC for up to 120 h, and in 83% at 168 h. A swirling pattern score of 2.5 or greater predicted with a specificity of 100% a good morphology score in the PC.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Platelets↗