Properties of overlapping genes are conserved across microbial genomes

There are numerous examples from the genomes of viruses, mitochondria, and chromosomes that adjacent genes can overlap, sharing at least one nucleotide. Overlaps have been hypothesized to be involved in genome size minimization and as a regulatory mechanism of gene expression. Here we show that overlapping genes are a consistent feature (approximately one-third of all genes) across all microbial genomes sequenced to date, have homologs in more microbes than do non-overlapping genes, and are therefore likely more conserved. In addition, the size, phase (reading frame offset), and distribution, among other characteristics, of overlapping genes are most consistent with the hypothesis that overlaps function in the regulation of gene expression. The upstream sequences and conservation of overlapping orthologs of two model organisms from the genus Prochlorococcus that have significantly different GC-content, and therefore different nucleotide sequences for orthologs, are also consistent with small overlapping sequence regions and programmed shifts in reading frame as a common mechanism in the regulation of microbial gene expression.     

Premenstrual anxiety and depression: comparison of objective psychological tests with a retrospective questionnaire

Increased anxiety and depression are among the most frequently reported psychological problems in women seeking help for severe symptomatic premenstrual change, but there has been little objective evaluation of these symptoms. We therefore examined the results of objective psychological testing in 40 women with no apparent psychiatric or psychological disorder who had reported moderate to extreme increased anxiety and depression on a retrospective assessment form. Scores on the State-Trait Anxiety Inventory and Institute of Personality and Ability Testing (IPAT) Depression Scale increased from the low symptom intermenstrual phase of the cycle (days 5-10) to the premenstrual phase (within the last 6 days of the cycle), suggesting that retrospective complaints of increased premenstrual anxiety and depression can be confirmed on objective psychological assessment. However, it was observed that the distribution of intermenstrual IPAT depression scores was bimodal. Cyclic changes varied among the tests depending upon the IPAT depression score. The study suggests that 2 populations may exist in this screened sample; one population appears to have "pure PMS" and the second groups manifests a premenstrual exacerbation of subclinical depression.     

In vivo imaging of rat lymphocytes with an indium 111-labelled anti-T cell monoclonal antibody: a comparison with indium 111-labelled lymphocytes

An indium 111-labelled mouse anti-rat T cell monoclonal antibody, MRC OX-19, was injected intravenously into rats to establish the usefulness of radiolabelled anti-lymphocyte antibodies in imaging lymphoid tissues. Antibody binding in vivo, measured by immunofluorescence analysis of cell suspensions made from lymphoid tissues, was detectable on lymphocytes in blood, spleen and lymph nodes. The extent of binding was time and antibody-dose dependent. Doses of antibody above 80 g/kg body weight resulted in modulation, i.e. loss of CD 5 (T 1) molecules from the cell surface, although the cells remained in the circulation. Modulation was demonstrable within 2 h and for at least 24 h after a single injection of antibody. Intravenous injection of¹¹¹In-MRC OX-19 resulted in levels of in vivo binding comparable with those seen with unlabelled antibody. Scintillation imaging showed early splenic localisation persisting over 48h, a more gradual localisation in the lymph nodes seen clearly at 24 h and a steady background. Comparison of the in vivo distribution of labelled antibody and¹¹¹In-tropolone-labelled lymphocytes showed that both could be used for external imaging of lymphocytes by scintillation camera.     

Effect of foot and ankle position on tarsal tunnel compartment pressure

Tarsal tunnel intracompartment pressures were determined in 10 fresh-frozen normal human adult cadaver specimens. With the foot and ankle held in mild plantarflexion and neutral eversion-inversion, mean tarsal tunnel pressure was minimal (2 +/- 1 mmHg). However, when the foot and ankle were positioned in full eversion, mean tarsal tunnel pressure increased to 32 +/- 5 mmHg (P < or = 0.005); in full inversion, mean pressure increased to 17 +/- 5 mmHg (P < or = 0.05). There was no significant difference in mean tarsal tunnel pressure between the everted and inverted positions. These results support the hypothesis that increased pressure within the tarsal tunnel when the foot is moved into the everted or inverted position may aggravate posterior tibial nerve entrapment. These findings may also provide an explanation for clinically observed aggravation of symptoms in these positions, night pain, and improvement of symptoms with neutral immobilization in some patients with tarsal tunnel syndrome.     

Molecular typing of Salmonella serotype Thompson strains isolated from human and animal sources

One-hundred-and-thirteen isolates of Salmonella serotype Thompson from diverse sources in seven countries were characterized by PvuII ribotyping and IS200 fingerprinting. Ten PvuII ribotypes were observed. The predominant PvuII ribotype 1 represented a major clone of world-wide distribution but was not found in Australia; PvuII ribotypes 2 and 3 represented minor clones. HincII ribotyping discriminated subtypes within PvuII ribotype 1: HincII ribotype 1 was distributed widely but HincII ribotype 2 was found mainly in Scottish isolates. None of 101 isolates of PvuII ribotypes 1-3 contained copies of IS200. All 12 isolates of PvuII ribotypes 4-10 were from Australia and 7 of them contained copies of IS200 of 5 different profiles. These results suggest the existence of at least two lineages of Salmonella Thompson with a different geographical distribution. The finding that most isolates from man and poultry in Scotland belonged to the same ribotype (PvuII 1/HincII 2) and were IS200-negative suggests that poultry is an important source of human infection in Scotland.     

A soluble androgen receptor in the cytoplasm of the male mastomys prostate

Summary A steroid receptor protein was isolated from the cytoplasmic fraction of Mastomys prostate. Following in vivo and in vitro labelling of the tissue with tritiated testosterone or dihydrotestosterone, samples were analysed by gel exclusion chromatography or sucrose density gradient centrifugation. A steroid receptor complex was isolated on Sephadex G-200. Analysis of the steroids associated with this complex showed that the major part of the bound radioactivity was 5 -dihydrotestosterone. The binding was inhibited by unlabelled testosterone and could not be demonstrated in the liver cytosol. Using sucrose desity gradient centrifugation, the dihydrotestosterone receptor complex sedimented at 5.6 s together with heavier aggregates. In the presence of 0.4 M KCl a single complex was sedimented at 4. 6 s. The results demonstrate a receptor protein in the cytosol of the Mastomys prostate which binds to dihydrotestosterone and is comparable to that of rat prostate.     

Intravesical Evans strain BCG therapy: quantitative immunohistochemical analysis of the immune response within the bladder wall.

Previous studies have demonstrated that is is the local immune response which is of importance for the anti-tumour activity of BCG therapy. We have investigated this by quantitative immunohistochemical analysis of serial bladder mucosal biopsies taken before, during and after an eight week course of intravesical Evans strain BCG therapy and three monthly thereafter in 16 patients (15 extensive CIS and one extensive G2pTa papillary tumour). This particular group of patients had a 67% complete response rate at six months post-treatment. The main findings on immunohistochemical analysis were the universal induction of MHC Class II antigens by urothelial cells which was statistically significant up to 6 months after completion of therapy, coupled with a T cell dominated cystitis. Increases in CD3+ T cell infiltration of the lamina propria and that of the CD4+ "Helper" subset which predominated were significant up to 3 months post-therapy and these cells showed evidence of increased immunological activation as shown by increased interleukin-2 receptor and MHC Class II antigen expression. There were also significant increases in CD68+ macrophage and the incidence of CD22+ B cell aggregates but CD57+ NK cells were sparse both before and after therapy. The degree of mononuclear cell infiltration for all markers examined (except CD57) was significantly greater in those biopsies in which the urothelial cells expressed MHC Class II antigens than in those that did not. Also the degree of T cell infiltration (CD3, CD4 and CD8) was significantly greater in the eight patients deemed to have had a complete response compared to those seven with a partial response or treatment failure. These results are discussed in terms of possible mechanisms of action for BCG therapy and in particular the role of enhanced antigen presentation by tumour cells.     

Insulin and glucagon responses of transplanted intrasplenic pancreatic islets.

Two transplant procedures have been investigated in which one third of the pancreas was autotransplanted into the splenic pulp of dogs. The two procedures consist of simple mechanical dissociation of the pancreas or mechanical dissociation followed by collagenase digestion. The ability of the endocrine segment of the transplant to survive and function was assessed by stimulation with arginine and measurement of insulin and glucagon response. The results demonstrate that both transplant procedures result in functioning beta and alpha cells that rapidly secrete both insulin and glucagon in response to arginine stimulation. However, greater insulin responses were obtained when mechanically dissociated but nonenzyme digested pancreatic tissue was used for transplantation. The spleen appears to be an excellent transplant site for the reception of endocrine pancreatic tissue and allowed both beta and alpha cells to survive following transplantation.