Diagnosis of Streptococcus pneumoniae pneumonia by quantitative enzyme linked immunosorbent assay of C-polysaccharide antigen.

AIMS--To evaluate the use of a quantitative enzyme linked immunosorbent assay (ELISA) detecting C-polysaccharide (PnC) antigen in sputum for the diagnosis of Streptococcus pneumoniae infection. METHODS--Specimens of sputum from 60 patients with acute community and hospital acquired pneumonia and infective exacerbations of obstructive airways disease were examined by semiquantitative culture and antigen ELISA. RESULTS--Using a cutoff value of 1 microgram/ml PnC antigen for a positive result, the sensitivity of this assay was 90.3%, specificity 93.1%, predictive value of a positive result was 93.5%, and the predictive value of a negative result 89.6%. CONCLUSIONS--Quantitation of C-polysaccharide antigen in sputum by ELISA distinguishes between carriage of oral bacteria which express PnC-like antigen and infection with S pneumoniae and compares favourably with other diagnostic methods.     

Temporal effects of a COX-2-selective NSAID on bone ingrowth

The effects of a short course of a COX-2 inhibitor on bone healing when the drug is discontinued are unknown. We examined the effects of rofecoxib on bone ingrowth over a 6-week period using a well-defined animal model. The Bone Harvest Chamber was implanted bilaterally in mature rabbits. After osseointegration of the chamber, the following treatments were given for 6 weeks each, followed by a harvest in each case: control-no drug; oral rofecoxib (12.5 mg/day) for the first 2 of 6 weeks; washout period-no drug; oral rofecoxib for the last 2 of 6 weeks; washout period-no drug; rofecoxib given continuously for all 6 weeks. Harvested specimens were snap-frozen, cut into serial 6-microm sections, and stained with hematoxylin and eosin and alkaline phosphatase (osteoblast marker), and processed using immunohistochemistry to identify the vitronectin receptor (osteoclast-like cells). Rofecoxib given continuously for 6 weeks yielded statistically less bone ingrowth compared to the control treatment. Rofecoxib given during the initial or final 2 weeks of a 6-week treatment did not appear to interfere with bone ingrowth. This suggests that the effects of COX-2 inhibitors on bone are less profound when the drug is administered for a short period of time.     

Mucin is produced by clara cells in the proximal airways of antigen-challenged mice

Airway mucus hypersecretion is a prominent feature of many obstructive lung diseases. We thus determined the ontogeny and exocytic phenotype of mouse airway mucous cells. In naive mice, ciliated (approximately 40%) and nonciliated (approximately 60%) epithelial cells line the airways, and > 95% of the nonciliated cells are Clara cells that contain Clara cell secretory protein (CCSP). Mucous cells comprise < 5% of the nonciliated cells. After sensitization and a single aerosol antigen challenge, alcian blue-periodic acid Schiff's positive mucous cell numbers increase dramatically, appearing 6 h after challenge (21% of nonciliated/nonbasal cells), peaking from Days 1-7 (99%), and persisting at Day 28 (65%). Throughout the induction and resolution of mucous metaplasia, ciliated and Clara cell numbers identified immunohistochemically change only slightly. Intracellular mucin content peaks at Day 7, and mucin expression is limited specifically to a Clara cell subset in airway generations 2-4 that continue to express CCSP. Functionally, Clara cells are secretory cells that express the regulated exocytic marker Rab3D and, in antigen-challenged mice, rapidly secrete mucin in response to inhaled ATP in a dose-dependent manner. Thus, Clara cells show great plasticity in structure and secretory products, yet have molecular and functional continuity in their identity as specialized apical secretory cells.     

Experimental analysis of the annotation of promoters in the public database

The ability to identify and examine promoter elements is important to researchers who wish to understand how gene expression is regulated in normal and pathological states. Unfortunately, the number of human promoters that have been directly experimentally defined is small. In order to determine if promoter sequences can be identified by simply aligning mRNA and genomic sequences, we have used a reporter gene assay to assess the promoter activity of the immediate 5' region flanking 38 mRNAs mapping to chromosome 21. For comparison, we have measured the activities of 19 sequences not thought to be promoters and 39 sequences taken from the Eukaryotic Promoter Database. Our results suggest that alignment of reference mRNAs to genomic sequence allows promoters to be identified for at least 75% of genes. These data provide the first empirical evidence that the current state of annotation of the genome is sufficient to allow molecular geneticists to correctly identify promoter sequences for most genes for which reference mRNA and genomic sequences are available.     

Complex karyotypic abnormality in ovarian fibroma associated with Gorlin syndrome

Nevoid basal cell carcinoma (NBCC) syndrome is an autosomal dominant disorder characterized by distinctive congenital malformations and a variety of benign and malignant neoplasms, including ovarian fibromas. We describe pathologic and cytogenetic findings in a large unilateral ovarian fibroma from a 12-year-old female with NBCC syndrome. The pathologic findings were characteristic for ovarian fibroma, but were unusual for the ovarian fibromas associated with NBCC syndrome because of the absence of calcification, the lack of bilaterality, and the presence of focal hypercellularity. The karyotype of tumor tissue showed complex numerical and structural abnormalities. Although there is frequent loss of heterozygosity of 9q22.3 and mutations in the PTCHgene in Gorlin syndrome, the ovarian fibroma in this case did not have cytogenetically detectable abnormalities of chromosome 9.     

Investigation of hormonal male contraception in African men: suppression of spermatogenesis by oral desogestrel with depot testosterone

BACKGROUND: Suppression of spermatogenesis to azoospermia is required for effective hormonal male contraception, but the degree of suppression varies between ethnic groups. We here report the first study of hormonal suppression of spermatogenesis in two African centres using a regimen of oral progestogen with depot testosterone. METHODS A total of 31 healthy men (21 black) were recruited in Cape Town and 21 men in Sagamu, Nigeria. Subjects were randomized to take either 150 or 300 micro g desogestrel daily p.o. with testosterone pellets. In Cape Town, desogestrel was administered for 24 weeks with 400 mg testosterone re-administered 12 weekly. In Sagamu, desogestrel was administered for 52 weeks with 200 mg testosterone (later increased to 400 mg) re-administered 12-weekly. RESULTS: In Cape Town, 22 men completed at least 20 weeks treatment. Azoospermia was achieved in 8/10 and 8/12 men in the 150 micro g and 300 micro g desogestrel groups. Four men in Sagamu withdrew. Azoospermia was achieved in all 17 men in the two groups. There were no significant changes in lipoprotein or haemoglobin concentrations in any group. CONCLUSION: These data demonstrate that the combination of oral desogestrel with depot testosterone is an effective regimen for suppression of spermatogenesis in African as in Caucasian and Chinese men, with azoospermia achieved in a total of 83/98 (85%) men.