The plastic envelope method, a simplified technique for culture diagnosis of trichomoniasis.

Although culture of Trichomonas vaginalis is more sensitive than wet mounts in the diagnosis of trichomoniasis, the lack of convenience of culture prevents it from being widely used. To improve the acceptability of diagnosis by culture, a plastic envelope method (PEM) was devised. PEM permits both immediate examination and culture in one self-contained system. The medium consists of dry ingredients that are reconstituted with water before use. The effectiveness of immediate examinations by PEM was compared with that of wet mounts, and the effectiveness of culture by PEM was compared with that of culture in Trichomonas Medium No. 2 (Oxoid). Of 710 vaginal secretion specimens from symptomatic and asymptomatic women that were tested by the four methods, 62 (9%) were positive for T. vaginalis. The sensitivity was 66% by wet mount, 66% by immediate examination by PEM, 89% by cultures in Oxoid medium, and 97% by culture by PEM. The two culture methods had equivalent sensitivities but were significantly (P less than 0.0001) more sensitive than the two immediate methods. The combined immediate examination by PEM plus culture was more convenient to use than wet mounts plus culture in Oxoid medium. The long shelf-life of PEM's dry medium and its anticipated low cost are additional advantages.     

Immunohistochemical, in situ hybridization, and ultrastructural localization of SARS-associated coronavirus in lung of a fatal case of severe acute respiratory syndrome in Taiwan

This article describes the pathological studies of fatal severe acute respiratory syndrome (SARS) in a 73-year-old man during an outbreak of SARS in Taiwan, 2003. Eight days before onset of symptoms, he visited a municipal hospital that was later identified as the epicenter of a large outbreak of SARS. On admission to National Taiwan University Hospital in Taipei, the patient experienced chest tightness, progressive dyspnea, and low-grade fever. His condition rapidly deteriorated with increasing respiratory difficulty, and he died 7 days after admission. The most prominent histopathologic finding was diffuse alveolar damage of the lung. Immunohistochemical and in situ hybridization assays demonstrated evidence of SARS-associated coronavirus (SARS-CoV) infection in various respiratory epithelial cells, predominantly type II pneumocytes, and in alveolar macrophages in the lung. Electron microscopic examination also revealed coronavirus particles in the pneumocytes, and their identity was confirmed as SARS-CoV by immunogold labeling electron microscopy. This report is the first to describe the cellular localization of SARS-CoV in human lung tissue by using a combination of immunohistochemistry, double-stain immunohistochemistry, in situ hybridization, electron microscopy, and immunogold labeling electron microscopy. These techniques represent valuable laboratory diagnostic modalities and provide insights into the pathogenesis of this emerging infection.     

B cell growth and differentiation factors interact with receptors distinct from the interleukin 2 receptor

Human B lymphocytes preactivated with Staphylococcus aureus Cowan strain I can proliferate and differentiate to Ig-secreting cells when cultured in the presence of recombinant interleukin 2 (IL2). We have compared 2 different B cell growth factors (BCGF) and a B cell differentiation factor (BCDF) to IL2 in the regulation of human B lymphocyte growth and differentiation. Utilizing a competitive binding assay, neither a high molecular weight BCGF (HMW-BCGF) nor a low molecular weight BCGF (LMW-BCGF) competitively inhibited the binding of radiolabeled IL2. Blocking studies with the anti-Tac monoclonal antibody demonstrated that B cell proliferation to IL2 was inhibited while a crude supernatant containing BCGF and IL2 was only partially inhibited. B cell Ig secretion induced by IL2 was also inhibited by anti-Tac while a crude supernatant and partially purified BCDF were not. Furthermore, IL2 plus BCGF was shown to enhance B cell proliferation better than either factor alone and IL2 plus a BCDF enhanced B cell Ig secretion better than either factor alone. By separating activated B cells into Tac-positive and Tac-negative fractions, much of the previously noted enhancement with the 2 factors was found to be secondary to the differential sensitivity of the 2 populations to BCGF and IL2 or BCDF and IL2. Thus, LMW-BCGF, HMW-BCGF and a partially purified BCDF appear to interact with receptors distinct from the IL2 receptor in mediating their effects on B cell growth and differentiation.     

Births of normal daughters after MicroSort sperm separation and intrauterine insemination, in-vitro fertilization, or intracytoplasmic sperm injection

The world's first deliveries of normal babies after use of flow cytometric separated human sperm cells (MicroSort) for preconception gender selection are reported. Offspring were of the desired female gender in 92.9% of the pregnancies. Most of these pregnancies and births were achieved after simple intrauterine insemination.      

A 3 year retrospective review of intrauterine insemination, using cryopreserved donor spermatozoa and cycle monitoring by urinary or serum luteinizing hormone measurements

Insemination with donor spermatozoa is an integral part of infertility treatment. For the last 3 years in our unit, intrauterine insemination with donor spermatozoa (IUID) has been used in preference to vaginal insemination. In this retrospective study, patients were offered an initial course of five single intrauterine inseminations with cryopreserved donor spermatozoa and treatment was then reviewed. A total of 389 patients received 1465 inseminations. In all, 1119 cycles were monitored using luteinizing hormone serum analyses and 346 cycles using the urine home test kits. The clinical pregnancy rate per insemination for the cycles monitored by the serum assay was 18.0% (202/1119) compared with the urine cycles (13.7%, 46/346) (P <05). The pregnancy loss rate was not significantly different (14.4%, 29/202 and 21.7%, 10/46) (serum and urine cycles respectively). The viable clinical pregnancy rate was significantly higher (P <03) for the serum cycles than for the cycles using the urinary monitoring (15.5%, 173/1119 and 10.4%, 36/346 respectively). The cycles monitored by serum assay had a significantly higher cumulative viable clinical pregnancy rate (P <0001) of 70.2% after nine inseminations compared with the urine monitored cycles of 54.8%. The majority of patients opted for the serum cycles, with a minority self-selecting the urine cycles mainly for travelling convenience. The explanation for the significant differences between the viable clinical pregnancy rates per insemination and the cumulative viable clinical pregnancy rates may be due to the sensitivity of the urine home test kit or the patients' interpretation of the result.