Specificity and sensitivity of RHD genotyping methods by PCR-based DNA amplification

We have compared the sensitivity and specificity of four PCR methods of RHD gene detection using different sets of primers located in the regions of highest divergence between the RHD and RHCE genes, notably exon 10 (method I), exon 7 (method II), exon 4 (method III) and intron 4 (method IV). Methods I–III were the most sensitive and gave a detectable signal with D-pos/D-neg mixtures containing only 0.001% D-positive cells. Moreover, method II could detect the equivalent DNA amount present in only three nucleated cells in the assay without hybridization of PCR products, whereas the sensitivity of the other methods was 10–50 times less. Investigation of D variants indicated that false-negative results were obtained with method II (D^IVb variant), method III (D^VI and DFR variants) and method IV (D^VI variants), but not method I. Weak D (D^u) was correctly detected as D-positive by all methods, but most cases of Rh_null appeared as false-positives, as they carry normal RH genes that are not phenotypically expressed. Some false-positive results were obtained with method I in a few Caucasian DNA samples serotyped as RhD-neg but carrying a C - or E -allele, whereas a high incidence of false-positives was found among non-Caucasian Rh-negative samples by all methods. In the Caucasian population, however, we found a full correlation between the predicted genotype and observed phenotype at birth of 92 infants. Although we routinely use the four methods for RHD genotyping, a PCR strategy based on at least two methods is recommended.     

A randomized trial to study first-line combination therapy with or without a protease inhibitor in HIV-1-infected patients

OBJECTIVE: To compare one protease inhibitor (PI)-based and two PI-sparing antiretroviral therapy regimens. METHODS: International, open label, randomized study of antiretroviral drug-naive patients, with CD4 lymphocyte counts >/= 200 x 106 cells/l and plasma HIV-1 RNA levels > 500 copies/ml. Treatment assignment to stavudine and didanosine plus indinavir or nevirapine or lamivudine. Primary study endpoint was the percentage of patients with plasma HIV-1 RNA levels < 500 copies/ml after 48 weeks in the intention-to-treat analysis (ITT). RESULTS: In total, 298 patients were enrolled. After 48 weeks, the percentage of patients in the indinavir, nevirapine and lamivudine arms with HIV-1 RNA < 500 copies/ml was 57.0%, 58.4% and 58.7%, respectively, in an ITT analysis. After 96 weeks of follow-up, these percentages were 50.0%, 59.6% and 45.0%, respectively. The percentage of patients with HIV-1 RNA < 50 copies/ml was significantly less for those allocated to lamivudine in an on-treatment analysis after 48 and 96 weeks of follow-up. Patients in the nevirapine arm experienced a smaller increase in the absolute number of CD4 T lymphocytes. There were no significant differences in the incidence of serious adverse events. CONCLUSIONS: A comparable virological response can be achieved with first-line PI-base and PI-sparing regimens. The triple nucleoside regimen utilized may be less likely to result in viral suppression to < 50 copies/ml, while the nevirapine-based regimen is associated with a lower increase in CD4 T lymphocytes.     

Complications of vascular access: results of a European multi centre study of the EDTNA/ERCA Research Board

The pilot project of the Research Board of EDTNA/ERCA handled the management of vascular accesses (VA) in European dialysis centres. In the first part of the study, centre policies related to VA management were investigated. In the second part of the study, individual patients were followed prospectively during one year. This paper reports on several topics of the second part of the project, investigating complications of the VA related to centre, patient characteristics and dialysis techniques used. Complications most frequently observed were thrombosis, stenosis, infection, bleeding and flow problems. Gradually more infections and flow problems were observed if the centre size and the patients/nurse ratio went up. Complication rate was not significantly influenced by age, gender, renal diagnosis, time on dialysis or medication used by the patient. In contrast, the number of vascular accesses in the past and interventions in the VA before first use resulted in an increased number of complications. Nurses have a key role in the prevention, manipulation and outcome of vascular access related complications.     

Phenylphenols,biphenols, bisphenol-A and 4-tert-octylphenol exhibit alpha and beta estrogen activities and antiandrogen activity in reporter cell lines

We previously demonstrated the interactions of different chemical compounds with estrogen receptors ERalpha and ERbeta and the androgen receptor (AR) using different reporter cell lines. In this study, we characterize the ERalpha, ERbeta and AR activity of different biphenyls using the same tools. We provide evidence that several phenyl derivatives present both estrogenic and antiandrogenic activity. The extent of hydroxylation and the position of the hydroxyl function were important in determining their estrogenicity and antiandrogenicity. Of the tested compounds, bisphenol-A and 4,4' biphenol had very high estrogenic activity, although it was lower than that of the strong estrogenic alkylphenol, 4-tert-octylphenol. Bisphenol-A and 4,4' biphenol were able to activate ERs at concentrations lower than 1 microM, whereas the other compounds only activated at concentrations above 1 microM. Interestingly, 4,4' biphenol was a better agonist for ERbeta than for ERalpha. No androgenic activity was detected for any of these compounds. Bisphenol-A, 3-OH phenylphenol, 4-OH phenylphenol and 4,4' biphenol exhibited antiandrogenic activity close to that of 4-tert-octylphenol (IC(50) approximately 5 microM). In whole cell binding assays, these compounds displaced [3H] R1881 with Ki = 10 microM. Although these Ki values seem high in comparison with that of hydroxyflutamide (0.4 microM), one must keep in mind that environmental chemicals can accumulate in adipose tissues for several years. In conclusion, these environmental chemicals may have a negative impact on androgen action during fetal and post-natal life.     

Intraluminal duodenal diverticulum

Summary A case of intraluminal duodenal diverticulum, detected by upper gastrointestinal roentgenogram is reported in a 54-year-old woman. The diagnosis was confirmed by gastroduodenal endoscopy. The typical diverticulum was attached to the posterior and internal wall of the descending duodenum, arose 1.0 cm below the papilla of Vater, and extended distally. The proximal extremity of the diverticulum presented a large aperture, and the pouch showed no distal orifice communicating with the duodenum. The internal and external surfaces of the diverticulum were both covered with normal duodenal mucosa. When surgical intervention, as in this case, is not required, gastroduodenal endoscopy alone permits an accurate differentiation of intraluminal diverticulum from incomplete mucous diaphragm prolapsed into the duodenum which strikingly resembles the diverticulum on x-ray films.     

Biokinetics and dosimetry of 111In-DOTA-NOC-ATE compared with 111In-DTPA-octreotide

Purpose

The biokinetics and dosimetry of ¹¹¹In-DOTA-NOC-ATE (NOCATE), a high-affinity ligand of SSTR-2 and SSTR-5, and ¹¹¹In-DTPA-octreotide (Octreoscan?, OCTREO) were compared in the same patients.

Methods

Seventeen patients (10 men, 7 women; mean age 60?years), referred for an OCTREO scan for imaging of a neuroendocrine tumour (15), thymoma (1) or medullary thyroid carcinoma (1), agreed to undergo a second study with NOCATE. Whole-body anterior–posterior scans were recorded 0.5 (100?% reference scan), 4, 24 and 48?h (17 patients) and 120?h (5 patients) after injection. In 16 patients the OCTREO scan (178?±?15?MBq) was performed 16?±?5?days before the NOCATE scan (108?±?14?MBq) with identical timing; 1 patient had the NOCATE scan before the OCTREO scan. Blood samples were obtained from 14 patients 5?min to 48?h after injection. Activities expressed as percent of the initial (reference) activity in the whole body, lung, kidney, liver, spleen and blood were fitted to biexponential or single exponential functions. Dosimetry was performed using OLINDA/EXM.

Results

Initial whole-body, lung and kidney activities were similar, but retention of NOCATE was higher than that of OCTREO. Liver and spleen uptakes of NOCATE were higher from the start (p?<?0.001) and remained so over time. Whole-body activity showed similar α and β half-lives, but the β fraction of NOCATE was double that of OCTREO. Blood T _1/2β for NOCATE was longer (19 vs. 6?h). As a result, the effective dose of NOCATE (105?μSv/MBq) exceeded that of OCTREO (52?μSv/MBq), and the latter result was similar to the ICRP 106 value of 54?μSv/MBq. Differential activity measurement in blood cells and plasma showed an average of <5?% of NOCATE and OCTREO attached to globular blood components.

Conclusion

NOCATE showed a slower clearance from normal tissues and its effective dose was roughly double that of OCTREO.     

Removal of an intra-pelvic socket: description of a safe surgical algorithm

Migration of an acetabular component beyond the ilio-ischial line is a rare but potentially lethal complication following a total hip arthroplasty, because the socket can become entrapped between the iliac vessels. Pre-operative assessment of the position of the socket relative to the intra-pelvic vascular structures is always mandatory to set up a staged procedure with a retroperitoneal exposure of the iliac vessels. This allows for a safe mobilization and looping of the vessels followed by extraction of the component either through the retroperitoneal or standard surgical approach to the hip joint. This strategy will minimize the risk of disruption of the vessels and of uncontrollable bleeding in case of vessel damage.