Search PubMed⌕ Search

Biomedical subjects

J Nusbacher

Publications and source records attributed to J Nusbacher.

At least 19 recordsLinked to original sources
PubMed1993

Acute normovolaemic haemodilution and idiopathic scoliosis surgery: effects on homologous blood requirements.

After the introduction of acute normovolaemic haemodilution(NVHD) in our hospital, we prospectively studied 19 patients managed with moderate NVHD (mean haematocrit 0.28, SD 0.02) during idiopathic scoliosis surgery (mean angle 53.2, SD 16.7 degrees) with the Cotrel-Dubousset instrumentation (CDI). Our standard scoliosis anaesthetic technique was used. Intraoperatively, one patient received one unit of homologous blood. Postoperatively, seven patients received ten units of homologous blood. Homologous blood used was reduced by about 83% for this procedure in our institution. In the assessment of fluid and blood requirements we found physical signs reflecting tissue perfusion and oxygen supply more reliable than the estimated blood loss using the suction bottle and swabs. The similar postoperative complications (nine fever, five atelectasis/pneumonia, one urinary infection, one phlebitis), anaesthetic duration (mean 5.21, SD 1.13) hours, hospitalisation (mean 6.67, SD 1.19) days and return to normal activity (mean 8, SD 7.68) weeks indicate that the NVHD patients did just as well as with our previous regimen when only homologous blood was used.

Adolescent↗
PubMed1992

Prevalence of antibody to human T-cell lymphotropic virus type I/II in people of Caribbean origin in Toronto.

OBJECTIVE: To estimate the prevalence of antibody to human T-cell lymphotropic virus type I/II (anti-HTLV-I/II) in people from an HTLV-I/II-endemic area (the Caribbean) living in a nonendemic region (Canada). DESIGN: Cross-sectional household survey. SETTING: Households in Toronto in 1989. PARTICIPANTS: A modified quota sampling method was used to recruit subjects of Caribbean origin as well as other Canadians. Of 2900 people invited to participate in the study 1323, 743 of Caribbean origin, were interviewed about their background and possible exposure to HTLV-I/II. MAIN OUTCOME MEASURES: Blood samples were analysed for anti-HTLV-I/II by means of an enzyme-linked immunoassay, the result being confirmed by the Western blot technique and radioimmunoprecipitation assay. The samples were also analysed for antibody to human immunodeficiency virus (anti-HIV) and hepatitis B surface antigen (HBsAg) and for surrogate markers of non-A, non-B hepatitis. RESULTS: A total of 853 blood samples (64.5%) were analysed, 483 (56.6%) from subjects of Caribbean origin. The proportion of subjects who agreed to give a blood sample was similar for the Caribbean and non-Caribbean strata. Eleven subjects, all of Caribbean origin (2.3% of the Caribbean stratum), were confirmed to be positive for anti-HTLV-I/II. There were no significant differences between the antibody-positive and antibody-negative subjects with respect to sex, age, racial origin or residence in the Caribbean for at least 22 years. All anti-HTLV-I/II-positive subjects were negative for anti-HIV and HBsAg, and four (36.4%) were positive for antibody to HBsAg and to hepatitis B core antigen. CONCLUSIONS: Except for origin, an association between antibody positivity and other factors could not be demonstrated. The findings suggest that blood donor screening might include place of origin in addition to the usual lifestyle or behavioural factors. However, the need to ensure safety of transfusion must be balanced against the need for participation of all groups in the blood transfusion program.

Adolescent↗
PubMed1989

Donor self-exclusion patterns and human immunodeficiency virus antibody test results over a twelve-month period.

Donor behavior in completing a pre-donation confidential self-exclusion form, which identified blood donors at high-risk of AIDS exposure, was evaluated. The form was completed by all donors during a 12 month period beginning in September, 1985. 188,824 units of blood were collected from 123,608 donors. On the first donation occasion 901 donors (0.73%) laboratory (LAB) designated, 224 (0.18%) did not complete the form correctly, and the remaining 122,483 transfusion (TRAN) designated. A greater proportion of LAB donors were men, under the age of 30 and had not donated in the previous two years than TRAN designated donors. Confirmed reactive anti-HIV, Western blot positive (WB+) results were greater in LAB than TRAN donors (1.664% vs 0.014%) on the first donation occasion. There were 43,982 donors who returned to donate on at least one other occasion. Of these, 43,778 designated TRAN initially, and only 217 (0.49%) changed their designation to LAB on any subsequent donation event. In contrast, of the 204 donors who designated LAB initially, 134 (65.6%) changed to TRAN on at least one other occasion. A variety of designation combinations from LAB to TRAN and back to LAB occurred. Thus, donors who initially LAB designated were more likely to change their designation on at least one other occasion than those who initially designated for TRAN. Of two donors who became anti-HIV WB positive on the second donation, one of these LAB designated on both occasions, was negative for anti-HIV by enzyme-linked immunoassay (EIA-) on the first donation but converted to EIA+, WB+ on the second.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

Longitudinal follow-up of blood donors found to be reactive for antibody to human immunodeficiency virus (anti-HIV) by enzyme-linked immunoassay (EIA+) but negative by western blot (WB-).

A cohort of 467 volunteer blood donors who were found to be EIA+/WB- was studied longitudinally for up to two years. EIA screening for anti-HIV and WB testing, regardless of the EIA result, was performed on all 769 subsequent donation events of this cohort to ascertain the consistency of test results over time. The following results were obtained: 1) 8.8% of subsequent donation events were EIA+; 2) Most donors who returned were found to be EIA-/WB-; 3) EIA-/WB? (indeterminate) was 14.5 times more common than EIA+/WB?; 4) EIA and WB results were generally inconsistent from donation to donation; 5) No donor was found to be WB+. These results suggest that, in a volunteer donor population, an EIA+/WB- result may have little value in predicting anti-HIV test results and AIDS infectivity in a future donation. The current practice of not using blood donated subsequently by EIA+/WB- donors unless a re-entry testing scheme is satisfactorily completed should be reconsidered.

Blood Donors↗
PubMed1986

Anti-Rho(D) in two Rh-positive patients receiving kidney grafts from an Rh-immunized donor.

Kidneys from an Rh-negative cadaver donor were transplanted to two Rh-positive patients. The donor's serum contained anti-Rho (D). In both patients, anti-Rho (D) was detected in their serum and on their red cells 3.5 weeks after transplantation. One patient had hemolysis. The antibodies persisted for nearly six months, despite graft rejection and nephrectomy in one case. These antibodies presumably arose from passenger B lymphocytes in the grafts from the Rh-immunized donor.

Anemia, Hemolytic↗
PubMed1985

Fc receptor-mediated binding and endocytosis by human mononuclear phagocytes: monomeric IgG is not endocytosed by U937 cells and monocytes.

Fc receptor-mediated endocytosis of monomeric IgG1 by human mononuclear phagocytes was evaluated under conditions where aggregated IgG and insulin readily undergo receptor-mediated internalization. U937 cells or normal human peripheral blood monocytes were incubated at 37 degrees C in the absence of free radioligand after having first bound 125I-IgG1 at 0 degrees C. To determine the amount of cell-associated IgG1 internalized after varying periods of 37 degrees C incubation, surface-bound IgG1 was removed by sequential exposure of cells at 0 degrees C to a nonspecific proteinase for 1 h and to acetic acid at pH 3.2 for 3 min. The failure to develop a proteinase- and acid-resistant fraction, similar to that seen over time at 37 degrees C in parallel experiments with 125I-insulin and 125I-aggregated IgG, and the lack of degradation of the IgG1 released into the medium from the same cells over time show that these cells do not endocytose and degrade monomeric IgG by an Fc receptor-specific mechanism and suggest that constitutive recycling without degradation is unlikely to be occurring. These data fulfill one prediction of the hypothesis that receptor-receptor interaction triggers Fc receptor-mediated endocytosis.

Cells, Cultured↗
PubMed1985

Characterization of a polyvalent antibody directed against the IgG Fc receptor of human mononuclear phagocytes.

We have raised an antibody to the IgG Fc receptor (FcR) of human mononuclear phagocytes by immunizing a goat with FcR purified by ligand affinity from a human monocyte line (U937). This antiserum, which inhibited the binding of IgG ligand to the receptors on U937, precipitated from detergent lysates of surface-radioiodinated U937 cells a 72 Kd sialoglycoprotein (p72) identified as the FcR by several previously published criteria. Two other bands seen in autoradiograms of SDS gels were precipitated by this antiserum: a 40 to 43 Kd band that co-purified with p72 and a 170 Kd protein that was not present in the immunogen. Fractionation of the IgG of this antiserum into two subclasses yielded one subclass (IgG1) in which anti-p72 activity was considerably enriched relative to antibody activities against other molecules. This antiserum precipitated p72 not only from U937 but from HL60 cells and from human peripheral blood monocytes as well, indicating common antigens on the p72 molecules from these three cells. However, p72 was not recovered from lysates of surface-iodinated human polymorphonuclear leukocytes or murine macrophage lines. Anti-p72 activity was not completely removed by adsorption with intact U937, suggesting that the antiserum recognizes portions of p72 that are not exteriorly disposed, perhaps noncarbohydrate portions of the molecule. We expect this antiserum to be useful for a number of studies of receptor structure and function.

Animals↗
PubMed1984

Intravenous gamma globulin in the treatment of chronic idiopathic thrombocytopenic purpura in adults.

Eight adult patients with chronic idiopathic thrombocytopenic purpura have been treated with an intravenous gamma globulin preparation. All patients received at least one "induction" course of intravenous gamma globulin for five consecutive days at a dose of 400 mg/kg per day. There were a total of 12 induction treatments. In five instances, patients also received single "maintenance" infusions of intravenous gamma globulin at the same dose. The mean peak increment in platelet count (X 10(3)/microliters) after induction was 87.3 +/- 42.37; after maintenance therapy it was 62.2 +/- 12.99. In only one instance was the platelet count increment less than 50 X 10(3)/microliters. In 13 of 17 intravenous gamma globulin treatments (both induction and maintenance), the platelet count returned to baseline or near-baseline levels within one to two weeks. In four instances, more prolonged remissions were observed. Measurements of platelet-associated IgG demonstrated the following: when platelet-associated IgG was greater than 100 ng/10(6) platelets, platelet-associated IgG usually decreased markedly after intravenous gamma globulin therapy. When platelet-associated IgG was less than 20 ng/10(6) platelets, platelet-associated IgG usually increased with therapy. There was no correlation between starting platelet-associated IgG levels or changes in platelet-associated IgG levels with therapy and the increment in the patient's platelet count.

Adult↗
PubMed1984

Pancreaticoduodenal transplantation in humans.

Whole cadaveric pancreata were transplanted to the pelvic extraperitoneal location in four patients with diabetes who previously had undergone successful cadaveric renal transplantation. One graft was lost within a few hours from venous thrombosis but with patient survival. The other three are providing normal endocrine function after two and a half, 11 and 12 months. The exocrine pancreatic secretions were drained into the recipient jejunum through enteric anastomoses. Because mucosal slough of the graft duodenum and jejunum in two patients caused a protein losing enteropathy and necessitated reoperations, we now do the pancreatic transplantation with only a blister of graft duodenum large enough for side-to-side enteroenterostomy. The spleen has been transplanted with the pancreas mainly for technical reasons, and this technique should have further trials in spite of the fact that delayed graft splenectomy became necessary in two recipients to treat graft induced hematologic complications.

Adult↗
PubMed1983

The effect of steroids and filtration leukapheresis on circulating hematopoietic progenitor cells.

Filtration leukapheresis (FL) in which donors are pretreated with steroids, induces a rapid neutropenia followed by neutrophilia. To investigate whether these phenomena are associated with changes in circulating progenitor cells (CFU-GM and BFU-E), 5 donors who underwent FL following steroid administration were compared with a control group who received steroids alone. Steroids alone caused an initial reduction in both circulating lymphocytes and committed progenitor cells followed by a rebound above baseline. Among donors undergoing FL, the changes in lymphocyte counts were identical to the steroid controls and the same early suppression of progenitor cells also occurred, but the rebound was blunted. Thus, the neutrophilia that occurs as a result of the FL procedure is not associated with an increase in circulating progenitor cells; and hence, the procedure does not appear to be a useful adjunct for increasing the yield of hematopoietic stem cells from the peripheral blood.

Female↗
PubMed1983

Non-centrifugal plasma collection using cross-flow membrane plasmapheresis.

A prototype of a cross-flow membrane plasmapheresis system was tested for its safety and efficacy in normal donors. 550 ml of plasma can be harvested in less than 1 h. The procedure appears to be safe for the donor. No significant alterations in donor hematological, coagulation, or biochemical values were obtained after the procedure compared to the predonation levels. Changes in the classical and alternate complement pathways were studied serially by analysis of functional hemolytic titers, C3 and C4 levels, and C3 and factor B cleavage products. No firm evidence of complement activation by the polysulfone filtration cell membrane was found.

Adult↗
PubMed1983

Long-term follow-up of donors cytapheresed more than 50 times.

11 volunteers who had donated white blood cells or platelets more than 50 times over a 5- to 9-year period were studied to determine whether any adverse consequences of many cytaphereses could be detected. Among the donors no significant differences were found in 18 hematological and biochemical parameters when compared to a group of age- and sex-matched nondonor controls. Despite extensive cumulative lymphocyte losses sustained by these donors, the ratio of T, B, helper and suppressor cells has been maintained within the normal range. No detrimental effects of multiple cytapheresis on the donors' health has been demonstrated to date.

Adult↗
PubMed1982

Health risk of leukapheresis donors.

The increasing use of normal donors for leukapheresis to provide granulocyte concentrates requires careful monitoring of recruitment and operational procedures to minimize donor health risks. Of 18,288 leuka- and leukaplateletphereses performed in American Red Cross regional blood services during a 12-month period, only 0.27% were discontinued because of acute donor reactions. None of these reactions had serious or long-term consequences for the donors. The potential toxicities of corticosteroids and hydroxyethyl starch, and the theoretical hazards of lymphocyte depletion, raise unanswerable questions concerning long-term safety, although no serious adverse reactions related to these factors have been observed. Critical factors for leukapheresis donor safety are: selective donor recruitment, adherence to operational protocols, and continuous and informed interest of physicians responsible for pheresis programs. Additional data are needed to assess the effects of repeated leukapheresis on donors and to establish rational guidelines for donor recruitment.

Adrenal Cortex Hormones↗