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.     

Nonopsonic phagocytosis of erythrocytes infected with ring-stage Plasmodium falciparum

Ring-stage parasitized erythrocytes (RPEs) were demonstrated to interact with effector cells of the innate immune system. With receptor blockade studies and CD36-null macrophages, human and murine macrophages were shown to phagocytose RPEs through the pattern recognition receptor CD36. These in vitro data implicate scavenger receptors in the clearance of RPEs.     

A national audit of the laboratory diagnosis of tuberculosis and other mycobacterial diseases within the United Kingdom

In order to audit United Kingdom laboratory diagnostic and reference services including novel molecular methods for tuberculosis, a questionnaire was sent to laboratories submitting specimens to the PHLS Mycobacterium Reference Unit (MRU) and regional centres and to the Scottish Mycobacteria Reference Laboratory (SMRL) in 1996-7. Nationally, 67.2% of laboratories responded. Most UK laboratories were fully or conditionally CPA accredited and take part in the NEQAS proficiency scheme. On average only 3.3% of primary samples submitted for mycobacterial diagnosis in 1995 produced a mycobacterial culture from approximately half as many patients (that is, a mean of 1488 specimens producing 49 isolates from 23 patients). Potentially over 380,000 specimens are processed for mycobacteria in the UK each year. The majority of laboratories use 4% NaOH +/- NALC for specimen decontamination. Culture on solid media was used by most laboratories and 62.9% also use liquid media. Most laboratories incubated cultures for eight weeks. Few laboratories use molecular diagnostic methods. Laboratories were most likely to use molecular methods for diagnosing tuberculous meningitis and for specimens from immunocompromised patients, although usage was strongly influenced by cost. Within England and Wales 43.9% (47/107) and 56% (61/109) of laboratories wanted a rapid service for rifampicin resistance detection in M tuberculosis from immunocompetent and immunocompromised patients, respectively. In regard to a tuberculous meningitis service, 80.5% (43/112) and 84.3% (102/121) of laboratories wanted this service for immunocompetent and immunocompromised patients, respectively. The quality of reference services was rated as "very good"/"good" by 85.6% of respondents nationally. Rapid molecular amplification diagnostic services were established at the PHLS MRU for rifampicin drug resistance detection nationally and for tuberculous meningitis at the MRU.     

Characterisation of Haemophilus spp. isolated from infant conjunctivitis

Haemophilus strains isolated from children under the age of 11 months with conjunctivitis were characterised by biotype, sugar fermentation, plasmid pattern and outer-membrane-protein profiles. H. influenzae was the most common species identified and was separated into 14 groups based on sugar fermentation and biotype patterns and into more than 20 groups when plasmid and outer-membrane-protein profiles were included. Small (mol. wt less than 10 X 10(6)) plasmids were identified in 11 of 34 (32%) H. influenzae isolates, 1 of 2 H. haemolyticus and 4 of 6 (67%) H. parainfluenzae isolates. Examination of sugar-fermentation and plasmid patterns increased the ability to distinguish between strains isolated at different times from recurrent disease and may have general applications in the study of Haemophilus strains isolated from a single anatomical site.     

Rapid detection of cytomegalovirus in bronchoalveolar lavage specimens by a monoclonal antibody method.

Cytomegalovirus (CMV), a common cause of pneumonia in immunocompromised subjects, is conventionally diagnosed in the laboratory by tube cell culture assays or by detection of characteristic inclusions in histologic sections. Of 160 immunocompromised patients, CMV infection was diagnosed in 19 subjects by bronchoalveolar lavage (BAL), using a monoclonal antibody directed against an early nuclear antigen of the virus. Cytospin preparations from BAL and MRC-5 cell cultures inoculated with the BAL specimens yielded positive results for 6 (31.6%) and 18 (94%) of the 19 subjects, respectively, within hours of the bronchoscopic procedure, whereas conventional tube cell cultures were positive for 11 of the 19 subjects (57.9%) only after an average of 9.3 days. The monoclonal antibody method permitted easy and rapid detection of CMV in BAL specimens.     

The pathogenicity of long versus short fibre samples of amosite asbestos administered to rats by inhalation and intraperitoneal injection.

For many years it has been accepted that fibre dimensions are the most important factor in the development of asbestos related disease with long fibres being more dangerous than short for all types of asbestos. This information has been derived from in vitro experiments and injection or implantation experiments since the kilogramme quantities of specially prepared dusts that are necessary for long term inhalation have not been available. The present study has taken advantage of the availability of a sample of amosite produced so that almost all fibres were less than 5 micron in length. The effects of this dust were compared to dust prepared from raw amosite that contained a very high proportion of long fibres. Previous data from studies with UICC amosite, which was intermediate in length, were also available for comparison. At the end of 12 months of dust inhalation, significantly more short fibre amosite was present in the lung tissue compared to the long but while the long fibre dust caused the development of widespread pulmonary fibrosis, no fibrosis at all was found in animals treated with short fibre. One third of animals treated with long fibre dust developed pulmonary tumours or mesotheliomas but no pulmonary neoplasms were found in animals treated with short fibre dust. Following intraperitoneal injection, the long fibre amosite produced mesotheliomas in 95% of animals with a mean induction period of approximately 500 days. With short fibre dust, only a single mesothelioma developed after 837 days. In previous inhalation studies with UICC amosite, relatively little pulmonary fibrosis had developed and only two benign pulmonary tumours. This would suggest that to produce a significant carcinogenic response in rat lung tissue amosite fibres must be longer than those in the UICC preparation. Following the injection of UICC amosite, however, mesotheliomas developed in the same proportion of animals and with the same mean induction period as with long fibre dust. From this it would appear that while very short fibres exhibit little carcinogenicity to either lung or mesothelial tissues, mesotheliomas can be produced by dust preparations consisting of shorter fibres than are needed to produce tumours.     

Elevation of serum sex hormone-binding globulin in females with fulminant hepatitis B virus infection

Amongst adults exposed to the hepatitis B virus (HBV), the infection pursues a fulminant course more frequently in females, while conversely a chronic carrier state is more frequent in males. Because of these differences in sex ratio, we investigated the relationship between the outcome of HBV infection and serum concentrations of sex hormone-binding globulin (SHBG), a circulating glycoprotein that exerts an important influence on the balance of free sex hormones. SHBG levels were significantly elevated in females with fulminant HBV infection compared to females with either uncomplicated acute or chronic HBV infection (P less than .05 and P less than .001, respectively). That this was not a nonspecific effect of fulminant hepatitis was confirmed by the significantly higher levels in this group than in age-matched females with fulminant hepatitis unrelated to HBV (P less than .05). In contrast, four of 15 female HBsAg carriers had SHBG values in the male range, and these included three of four patients who had acquired HBV as adults. SHBG levels were normal in all male groups. These results suggested that for adults the hormonal environment may be important in determining the course of HBV infection.