Determination of human platelet antigen frequencies in the Dutch population by immunophenotyping and DNA (allele-specific restriction enzyme) analysis

Platelets from 200 random Dutch blood donors were typed for the human platelet alloantigens HPA-1 to -5 recognized at present and for Naka. Naka is an epitope on glycoprotein IV, not expressed on the platelet of individuals with hereditary GP IV deficiency. Platelet immunofluorescence and monoclonal antibody-specific immobilization of platelet antigens (MAIPA) were applied for this purpose. The observed phenotype frequencies were 97.86% and 28.64% for HPA-1a and -1b, 100% and 13.15% for HPA-2a and -2b, 80.95% and 69.84% for HPA-3a and -3b, 100% and 0% for HPA-4a and -4b, 100% and 19.7% for HPA-5a and HPA-5b, respectively. Platelets from all donors reacted with the anti-Naka antibodies. To determine the gene frequencies for the HPA-1, HPA-2 and HPA-3 systems directly, DNA from 98 of these donors was isolated from peripheral blood mononuclear leucocytes and specific fragments were amplified by polymerase chain reaction (PCR). The fragments were analyzed using allele-specific restriction enzymes (ASRA). In all amplified PCR products an "internal control" for each assay, ie, a restriction site for the applied enzyme independent from the phenotype of the donor was present. In all donors tested, phenotypes, as determined by serological methods and genotypes, directly determined by the ASRA, were identical. Thus, the PCR-ASRA described in this report is a practical and reliable technique for the determination of alleles that code for platelet antigen allotypes, at least in the Dutch population.     

Targeted disruption of the murine tissue factor gene results in embryonic lethality

Tissue factor (TF) is an integral membrane glycoprotein that is believed to be the physiologic initiator of the blood coagulation cascade. Disruption of the mouse tissue factor gene leads to embryonic lethality between days E9.5-E11.5 of gestation. On E9.5, TF(-/-) embryos appear indistinguishable from their TF(+/+) and TF(+/-) littermates. By E10.5, TF(-/-) embryos are severely growth retarded, appear nearly bloodless, and are in most cases dead. Initial observations suggest that TF(-/-) embryos are dying of circulatory failure. Approximately 15% of the TF(-/-) embryos survive beyond E10.5, but none complete gestation. Heterozygotes appear normal and free of bleeding complications.     

Risk and significance of endoscopic/radiological evidence of recurrent Crohn's disease

BACKGROUND & AIMS: The aim of this study was to determine the risk of endoscopic/radiological recurrence of Crohn's disease postoperatively and the long-term outcome. METHODS: A randomized placebo-controlled trial was performed to determine the effectiveness of mesalamine in preventing recurrent Crohn's disease postoperatively. Patients in the control group were examined endoscopically/radiologically before entry into and annually during the trial. Findings were classified as minimal or severe. RESULTS: There were 76 patients (49 men and 37 women; mean age, 37.1 +/- 13.2 years). Fifty (61.7%) had terminal ileal resections. Overall, 55 endoscopic/radiological recurrences were observed in 51 patients (67.1%). Expressed actuarially, the recurrence rate was 27.5% at 1 year (95% confidence interval [CI], 15.8%-37.6%), 60.8% at 2 years (95% CI, 46%-71.3%), and 77.3% at 3 years (95% CI, 62.7%-86.3%). Nineteen (37%) were symptomatic and 12 (24%) were initially asymptomatic but later became symptomatic (mean, 13.0 +/- 8.8 months), whereas 20 (39%) remained asymptomatic (mean, 16.9 +/- 17.4 months). Patients with severe endoscopic/radiological disease were significantly more likely to be or become symptomatic than those with minimal disease (23 of 32 vs. 8 of 19, respectively; P = 0.0437). CONCLUSIONS: This study suggests that postoperative endoscopic/radiological recurrences occur later than previously reported. Furthermore, many of these patients, especially with minimal disease, will remain asymptomatic. (Gastroenterology 1997 Dec;113(6):1823-7)     

Mineral metabolism, bone histomorphometry and vascular calcification in alternate night nocturnal haemodialysis

BACKGROUND: Poor control of bone mineral metabolism (BMM) is associated with renal osteodystrophy and mortality in dialysis-dependent patients. The authors explored the efficacy of alternate nightly home haemodialysis (ANHHD) in controlling BMM parameters and its effects on bone mineral density and histomorphometry. METHODS: In this prospective observational study, 26 patients on home haemodialysis (3-5 h, 3.5-4 sessions weekly) were converted to ANHHD (6-9 h, 3.5-4 sessions weekly). Biochemical parameters of BMM at baseline, 6 and 12 months, radiological parameters at baseline and 12 months and bone histomorphometry at 12 months are described. RESULTS: Pre-dialysis serum phosphate fell from 2.13+/-0.65 to 1.38+/-0.35 mmol/L; P<0.0001. No binders were required in 77.2% compared with 7.7% at baseline. Calcium-phosphate product fell from 5.28+/-1.64 to 3.42+/-0.88 mmol2/L2; P<0.0001 and parathyroid hormone (PTH) from 301 (110-471) to 127 (47-240) ng/L; P=0.01. Bone mineral density remained stable. Vascular and ectopic calcification improved or stabilized in 87.5%. Bone histomorphometry at 12 months showed high, normal and low bone turnover in 10, 3 and 4 patients, respectively, with 6/17 patients having abnormal mineralization. CONCLUSION: Alternate nightly home haemodialysis effectively manages biochemical parameters of BMM. Patients with very high PTH at baseline (>1000 ng/L) did not significantly improve parathyroid hormone status. Abnormal bone turnover and mineralization were present in a significant proportion of patients at 12 months but low turnover was uncommon. Vascular calcification was stabilized or improved in the majority. ANHHD compares favourably with every night and short daily therapy in relation to BMM management and may offer lifestyle advantages for patients.     

利福昔明：有效维持肝性脑病缓解

肝性脑病是的一种慢性消耗性的肝硬化并发症。利福昔明（rifaximin）,一种口服的抗生素,治疗急性肝性脑病的疗效已有报道,但其预防此病疗效未知。     

Trace elements in end-stage renal disease – unfamiliar territory to be revealed

Although associated with unfavorable outcomes in the general population, abnormal blood levels of various trace elements have not been consistently studied in the end-stage renal disease population (with the notable exception of aluminum). This is surprising, as the uremic patient treated by chronic dialysis loses one major route of trace element excretion and is exposed systematically to a foreign environment (the dialysis fluid) possibly contaminated with significant amounts of potential deleterious trace elements. Moreover, some biological important trace elements may be lost through the dialysis membrane. Most studies to date demonstrated significantly altered blood levels of trace elements in ESRD patients compared to healthy controls. However, the biological impact of these abnormalities in renal disease is largely unknown and should be clarified by future studies. A further step would be the design of well-controlled randomized interventional studies, examining the potential therapeutic benefit of supplementing one or more trace elements in ESRD patients, a population characterized by an impressive mortality due to cardiovascular, infectious and neoplasic disease.     

Massage therapy after heart surgery: possibly pleasant,but not effective

Albert NM, Gillinov AM, Lytle BW, Feng J, Cwynar R, Blackstone EH. A randomized trial of massage therapy after heart surgery. Heart Lung 2009; 38: 480–90.     

Computer simulation in conjunction with medical thermography as an adjunct tool for early detection of breast cancer

Background

Mathematical modelling and analysis is now accepted in the engineering design on par with experimental approaches. Computer simulations enable one to perform several 'what-if' analyses cost effectively. High speed computers and low cost of memory has helped in simulating large-scale models in a relatively shorter time frame. The possibility of extending numerical modelling in the area of breast cancer detection in conjunction with medical thermography is considered in this work.

Methods

Thermography enables one to see the temperature pattern and look for abnormality. In a thermogram there is no radiation risk as it only captures the infrared radiation from the skin and is totally painless. But, a thermogram is only a test of physiology, whereas a mammogram is a test of anatomy. It is hoped that a thermogram along with numerical modelling will serve as an adjunct tool. Presently mammogram is the 'gold-standard' in breast cancer detection. But the interpretation of a mammogram is largely dependent on the radiologist. Therefore, a thermogram that looks into the physiological changes in combination with numerical simulation performing 'what-if' analysis could act as an adjunct tool to mammography.

Results

The proposed framework suggested that it could reduce the occurrence of false-negative/positive cases.

Conclusion

A numerical bioheat model of a female breast is developed and simulated. The results are compared with experimental results. The possibility of this method as an early detection tool is discussed.