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Flow cytometry techniques for immunophenotyping have revolutionised the diagnosis and monitoring of paediatric immunological disorders. Although recent studies in adult subjects discourage the use of density gradients for cell preparation prior to phenotyping, these procedures continue to be used. The purpose of this study was to determine the effect of density gradient separation on lymphocyte phenotypes from neonates, infants, and adults as compared to whole blood determinations. Subset distributions were different with the two procedures. In all three groups, CD19+ (B cell) and CD8+ (suppressor/cytotoxic T cell) percentages were significantly lower and CD3-CD56+ (NK cell) percentages were significantly higher in the density gradient separated cells. The loss of CD8+ cells in density gradient separation was shown to be a selective event. The CD8+CD11b- (cytotoxic T) subset percentages were lower in the density gradient separated cells, while the percentages of CD8+CD11b+ (suppressor T) cells were not affected by separation procedure. Because of the selective loss of lymphocytes on density gradients, the use of a whole blood technique for immunophenotyping in paediatric subjects is recommended.

The role of peritoneal lymphocytes in host immunity for continuous ambulatory peritoneal dialysis (CAPD) patients is just beginning to be understood. CAPD therapy increases the proportion of peritoneal lymphocytes, most of which demonstrate signs of activation. There are decreased peritoneal T cells and increased peritoneal B cells as compared to the patients' peripheral blood. When studies examine immunophenotypes of peripheral and peritoneal lymphocytes over time, no significant changes are found. Although changes in peritoneal lymphocyte subsets occur during peritonitis episodes, there are no changes in peripheral blood lymphocytes. The purpose of this article is to provide a brief review of research that has studied lymphocytes in CAPD patients.

The overall goal of this study was to examine the relationship among work stressors, burnout, and sense of coherence (SOC) in dialysis nurses. Two hundred thirty-eight registered nurses from 56 dialysis units completed a demographic data form, the Nursing Stress Scale, the Maslach Burnout Inventory, and Antonovsky's Sense of Coherence Scale. The results indicated that work load was the major contributing factor to both overall stress and burnout. Understanding the stressors that affect responses to the work environment will allow for successful interventions to alter the risk of exhaustion and burnout.

This article presents an overview of thermoregulatory mechanisms, the pathophysiology of fever, and alterations of the febrile response in end stage renal disease (ESRD) patients. Many ESRD patients do not exhibit the expected rise in white blood cell count or body temperature during clinical and laboratory-confirmed infections. Therefore, leukocytosis and fever cannot be relied on for the diagnosis of bacterial infection in ESRD patients.

Although a few studies have analyzed the characteristics of peritoneal lymphocytes from continuous ambulatory peritoneal dialysis (CAPD) patients, there have been no definitive longitudinal investigations comparing peripheral blood lymphocytes (PBL) with peritoneal lymphocytes (PL) from these patients. Therefore, the purpose of this study was to prospectively compare the phenotypes of PBL and PL of CAPD patients and to determine if phenotypic changes occurred from the initiation of CAPD therapy over the subsequent 12 months. Patients were categorized into younger (60 years) or older (60 years) to determine if age-related factors contributed to differences in lymphocyte phenotypes. Blood and overnight peritoneal dialysate effluents (PDE) were obtained from 18 patients at the initiation of CAPD therapy and for 11 successive months. Fourteen lymphocyte subsets were quantitated using monoclonal antibodies and flow cytometry analysis. CAPD patients had significantly higher percentages of peripheral activated T (CD3+/HLA-DR+) cells and natural killer (CD57+) cells at the beginning of CAPD than normal controls. There were significantly greater percentages of B cells, activated T cells, and suppressor T (CD8+/CD11b+) cells and significantly fewer helper T (CD4+) cells in the PDE as compared with the patients' peripheral lymphocytes. No significant changes were observed over time in the phenotypes of PBL and only one PL phenotype showed significant changes with fluctuating levels of CD4+/CD45RA+ cells with continued peritoneal dialysis. In general, these findings suggest that although both PBL and PL activation is occurring in clinically uninfected patients, the characteristics of lymphocytes are stable over time.

The purpose of this study was to phenotypically characterize and compare peripheral blood monocytes from CAPD patients with peritoneal macrophages isolated from their peritoneal dialysis effluents. Monocytes/macrophages were labeled with fluorescent ligands or monoclonal antibodies specific for 1) receptors for C5a, formyl-met-leu-phe (fMLP); Fc region of IgG; C3b (CR1); and C3bi (CR3), 2) Class II histocompatibility antigens HLA-DR and HLA-DQ; and 3) monocyte/macrophage surface antigen CD14. The cells were analyzed using flow cytometry. Results indicated that there were no differences between monocytes and peritoneal macrophages in their receptor expression for fMLP, CR1, or CR3. However, paired t-testing indicated that peritoneal macrophages had significantly increased expression of Fc and C5a receptors, as well as enhanced antigen expression of HLA-DR, HLA-DQ, and CD14. These results suggest that peritoneal macrophages from CAPD patients are activated with increased expression of receptors and antigens important in host defense.

An intercomparison of standards of mass of 50 g and 10 g was carried out between the national standards laboratories of four European countries during the period May 1988 to July 1989. The transfer standards used were carefully selected by the pilot laboratory (NPL) and the comparison scheme was chosen to minimise the influence of any instability in their mass. The results obtained show good agreement to within the uncertainties of measurement of the participants, the widest variation in mass value between any two participants being 8 μg at 50 g and 3 μg at 10 g.

An international comparison in the pressure range 20 - 100 MPa has been carried out under the auspices of the high-pressure working group of the Comite Consultatif pour la Masse et les grandeurs apparentees (CCM) of the Comite International des Poids et Mesures (CIPM). The Standards Laboratories of 13 countries have participated in this comparison, which took place during the period 1981 - 1985. This paper presents a resume of the comparison. The transfer standard used was an oil-operated pressure balance. Each laboratory determined the effective area of the piston-cylinder assembly of this balance in the pressure range 20 - 100 MPa. The results of the measurement of the effective area extrapolated to zero applied pressure agreed within 204 parts per million (ppm) for all 13 laboratories (9 laboratories agreed within 53 ppm). The results of the measurement of the effective area at 100 MPa agreed within 414 ppm for all 13 laboratories (8 laboratories agreed within 78 ppm).

We have developed a reversed-phase liquid-chromatographic procedure for simultaneously determining phenylalanine and tyrosine in serum and eluates of dried blood spots. Batch derivatization with phenylisothiocyanate and a 10-min linear gradient chromatographic assay with ultraviolet absorbance detection provide rapid sample throughput. Interrun precision (CV) is less than 12%; analytical recovery (from blood spot samples) exceeds 85%. Results for patients' samples correlate well with those from an amino acid analyzer and we encountered no apparent interferences. The speed and specificity of this assay facilitate the rapid diagnosis and monitoring of patients with phenylketonuria.

Vesicocolic fistula due to diverticular disease of the colon is conventionally treated by resection of the diseased bowel and closure of the vesical defect. Three cases are described in which separation of the viscera and simple suture of the vesical and colonic defects was carried out. A greater omental graft was interposed between the rectum and bladder. Two of the patients are well 12 and 26 months postoperatively. The third patient died a year postoperatively from a complication of her diverticular disease.

An international intercomparison in the pressure range 20-100 MPa has been organised under the auspices of the International Bureau of Weights and Measures. A brief outline is given of the results of the first of three phases in which the national standards laboratories of France, Italy, the United Kingdom, the United States of America and West Germany participated. These results show good agreement when considered in conjunction with the estimates of the uncertainty of measurement.

We reviewed seven patients with coronal fractures of the lateral femoral condyle and studied the mechanism of injury and the radiological features. The influence of soft tissue attachments on the displacement and the blood supply were investigated by clinical and cadaveric studies. All three fractures which were initially undisplaced lost position early during conservative management. Internal fixation gave good results at review, and is recommended to avoid the risk of malunion and possible secondary osteoarthritis.

Chronic renal failure patients on dialysis have an increased susceptibility to infection. Previous studies have demonstrated that these patients have a decreased in vitro neutrophil (PMN) chemotactic response and a reduction in C5a receptor availability on both PMN and monocytes. This study was designed to determine if other chemotactic factor-mediated responses of PMN and monocytes from hemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD) patients are abnormal. The responses investigated included in vitro chemotaxis, superoxide generation, H2O2 production, and myeloperoxidase (MPO) release. These studies showed that PMN from HD and CAPD patients are significantly decreased in their chemotactic response to both C5a and fMLP when compared to normal controls. The response of HD patient's PMN to C5a was decreased by an average of 55.1% (p less than 0.005) and for CAPD patients by 49.7% (p less than 0.01). Similarly, chemotactic responses to fMLP were decreased by an average of 44.7% (p less than 0.005) for HD patients and 36.3% (p less than 0.02) for CAPD patients. Superoxide anion production by PMN and monocytes from HD and CAPD patients in response to C5a and fMLP was also significantly decreased compared to controls. PMN superoxide production in response to C5a was decreased by an average of 36.5% (p less than 0.001) for HD patients and 32.0% (p less than 0.001) for CAPD patients. fMLP-stimulated production of superoxide was also decreased but to a lesser degree with a mean decrease of 18.0% (p less than 0.01) for HD patients and 24.1% decrease (p less than 0.01) for CAPD patients. This decreased responsiveness was restricted to C5a- and fMLP-stimulated superoxide production since phorbol myristate acetate (PMA)-stimulated responses were comparable to controls. A similar pattern of decreased superoxide production was found with monocytes from these patients. Comparable decreases in chemotactic factor-stimulated responses were also observed in a flow cytometric assay of H2O2 production in both PMN and monocytes and an in vitro assay of MPO release from PMN. Analysis of the binding of fluorescent C5a to PMN showed a direct correlation between decreased C5a binding and decreased O2- production and MPO release. Since all of these chemotactic factor-stimulated events are involved in the inflammatory process and the killing of microorganisms, alterations in these WBC functions in dialysis patients may contribute to their increased susceptibility to infection.

Chronic renal failure patients have an increased risk for infection which may partially be due to altered chemotactic ability of their white blood cells. This study was designed to evaluate chemotactic factor and Fc receptor expression on neutrophils (PMN) and monocytes from chronic renal failure patients on hemodialysis (HD) or continuous ambulatory peritoneal dialysis (CAPD). Analysis of these receptors was performed using flow cytometry and fluorescent chemotactic factors (C5a, f-Met-Leu-Phe-Lys [fMLPL] and casein) and heat-aggregated human IgG. Peripheral blood PMN and monocytes obtained from 14 HD patients (in the predialysis period) and 14 CAPD patients were analyzed for their ability to bind each of the fluoresceinated ligands. PMN and monocytes from both patient groups had a significant reduction in their ability to bind C5a. The average percentage (+/- s.e.m.) of PMN that bound C5a was 93.9 +/- 1.1 for the controls, 72.9 +/- 3.8 for HD patients, and 79.3 +/- 4.0 for CAPD patients. Similar results were obtained with monocytes with 69.7 +/- 1.9% for controls, 54.6 +/- 4.5% for HD patients, and 31.0 +/- 4.5% for CAPD patients. These differences in C5a binding were also reflected in the average intensity of fluorescence. There was no significant difference in the percentage or fluorescence intensity of PMN or monocytes that bound casein or aggregated IgG when either group of dialysis patients was compared to the control values. Binding of fMLPL by PMN and monocytes from the HD patients and PMN from the CAPD patients were similar to control values but the binding of fMLPL by monocytes from CAPD patients was significantly suppressed (p less than 0.03).(ABSTRACT TRUNCATED AT 250 WORDS)

Peripheral white blood cells (WBCs) of chronic ambulatory peritoneal dialysis (CAPD) patients show a reduced expression of chemotactic receptors and a desensitization to chemotactic factor induced events. Chronic complement activation has been suggested as a cause of such phenomena, resulting from either uremia, the indwelling peritoneal catheter, and/or dialysis fluid stimulation. The presence of complement activation products in peritoneal dialysis effluent was assessed by longitudinal measurement of C3bi in eight patients over a 6 to 8 month period, while peritoneal polymorphonuclear leukocyte (PMN) and monocyte CR3 and C5a receptor expression was quantitated by flow cytometry. In six of eight patients, C3bi levels were stable over time and usually measured less than 5 micrograms/ml. Two other patients showed periodic elevation of C3bi, which was not associated temporally with peritonitis. Further study is required to identify the origin of such activated complement components within the peritoneal cavity. However, no correlation was found between dialysate C3bi levels and peritoneal PMN or monocyte expression of CR3 or C5a receptors. Furthermore, the incidence of peritonitis for the two individuals with elevated C3bi was discordant (1 episode/8 patient months vs. 0 episodes/32 patient months), suggesting little or no relationship between these parameters.