Dysregulation of protein synthesis and disease.

The regulation of protein synthesis plays as important a role as transcriptional control in the control of gene expression. Once thought solely to act globally, translational control has now been shown to be able to control the expression of most genes specifically. Dysregulation of this process is associated with a range of pathological conditions, notably cancer and several neurological disorders, and can occur in many ways. These include alterations in the expression of canonical initiation factors, mutations in regulatory mRNA sequence elements in 5' and 3' untranslated regions (UTRs), such as upstream open reading frames (uORFs), internal ribosome entry segments (IRESs) and micro-RNA (miR) target sites, and the altered expression of trans-acting protein factors that bind to and regulate these elements. Translational control is increasingly open for study in both fresh and fixed tissue, and this rapidly developing field is yielding useful diagnostic and prognostic tools that will hopefully provide new targets for effective treatments.

The pathogenesis of mesothelioma is driven by a dysregulated translatome.

Malignant mesothelioma (MpM) is an aggressive, invariably fatal tumour that is causally linked with asbestos exposure. The disease primarily results from loss of tumour suppressor gene function and there are no 'druggable' driver oncogenes associated with MpM. To identify opportunities for management of this disease we have carried out polysome profiling to define the MpM translatome. We show that in MpM there is a selective increase in the translation of mRNAs encoding proteins required for ribosome assembly and mitochondrial biogenesis. This results in an enhanced rate of mRNA translation, abnormal mitochondrial morphology and oxygen consumption, and a reprogramming of metabolic outputs. These alterations delimit the cellular capacity for protein biosynthesis, accelerate growth and drive disease progression. Importantly, we show that inhibition of mRNA translation, particularly through combined pharmacological targeting of mTORC1 and 2, reverses these changes and inhibits malignant cell growth in vitro and in ex-vivo tumour tissue from patients with end-stage disease. Critically, we show that these pharmacological interventions prolong survival in animal models of asbestos-induced mesothelioma, providing the basis for a targeted, viable therapeutic option for patients with this incurable disease.

Heparin therapy for complications of placental dysfunction: a systematic review of the literature.

OBJECTIVE: To assess the benefits and harms of antenatal antithrombotic therapy for women at risk of adverse pregnancy outcomes associated with placental dysfunction. SEARCH STRATEGY: PUBMED and the Cochrane Controlled Trials Register (CENTRAL) were searched. Reference lists of retrieved studies were searched by hand. No date or language restrictions were placed. Date of last search February 2008. SELECTION CRITERIA: Randomized controlled trials comparing antenatal antithrombotic therapy (alone or combined with other agents) with placebo or no treatment were considered. Cohort studies with an appropriate control group were also considered. Studies were evaluated independently for appropriateness for inclusion and methodological quality without consideration of their results. Our search strategy identified five case series, two cohort studies with a control group, and one randomized controlled trial. All of the case series and one of the cohort studies were excluded. DATA COLLECTION AND ANALYSIS: The methodological quality of the included studies was poor. There was considerable variation in methodology and the interventions. It was not appropriate to combine results in meta-analysis. MAIN RESULTS: From the randomized trial, heparin was not associated with a reduction in preterm birth less than 37 weeks gestation (Heparin 5/68 versus Control 7/39; relative risk (RR) 0.41; 95% confidence intervals (CIs) 0.14-1.20), or birth weight below 10th centile (Heparin 4/68 versus Control 6/39; RR 0.38; 95% CI 0.11-1.27). CONCLUSION: There is insufficient information to recommend the use of heparin during pregnancy for women at risk of complications due to placental dysfunction. Further information from randomized trials is required.

Distal tunnel placement improves scaphoid flexion with the Brunelli tenodesis procedure for scapholunate dissociation.

PURPOSE: Treatment of scapholunate dissociation remains difficult. The modified Brunelli procedure, a flexor carpi radialis tenodesis through the scaphoid and secured with dorsal wrist ligaments, has shown promising results. This study compares the biomechanical effects on scaphoid flexion and scapholunate gap between proximal and distal tunnel placement in the modified Brunelli procedure. METHODS: Eight fresh-frozen cadaveric forearms were used. A dorsal approach to the wrist through the floor of the fourth compartment was used. Metallic markers were implanted into the scaphoid and lunate. Tunnels were drilled through the proximal and distal poles of the scaphoid. Wrists were positioned in neutral and loaded to 100 N through the wrist flexor and extensor tendons. Posteroanterior and lateral radiographs were taken with the scapholunate interval intact, with the scapholunate interval sectioned, and after the modified Brunelli tenodesis was performed through the proximal and then distal tunnels using Mersilene tape. Radiographs were analyzed for change in scapholunate angle and scapholunate gap. Multivariate analysis of variance was performed to assess statistical significance for each state compared with the intact wrist. RESULTS: In the intact wrist, the mean scapholunate gap was 1.6 mm +/- 0.1. With the scapholunate interval sectioned, the scapholunate angle increased by 26 degrees +/- 12 and gap increased to 4.2 mm +/- 1.2. With a proximal tunnel for the modified Brunelli procedure, the change in scapholunate angle decreased to 15 degrees +/- 10 and gap decreased to 1.8 mm +/- 0.3. With a distal tunnel for the modified Brunelli procedure, the change in scapholunate angle decreased to 4 degrees +/- 7 and gap decreased to 1.3 mm +/- 0.2. CONCLUSIONS: These biomechanical data suggest that a tunnel exiting in the distal pole of the scaphoid results in better correction of scaphoid flexion when performing the modified Brunelli procedure.

Stella is a maternal effect gene required for normal early development in mice.

stella is a novel gene specifically expressed in primordial germ cells, oocytes, preimplantation embryos, and pluripotent cells. It encodes a protein with a SAP-like domain and a splicing factor motif-like structure, suggesting possible roles in chromosomal organization or RNA processing. Here, we have investigated the effects of a targeted mutation of stella in mice. We show that while matings between heterozygous animals resulted in the birth of apparently normal stella null offspring, stella-deficient females displayed severely reduced fertility due to a lack of maternally inherited Stella-protein in their oocytes. Indeed, we demonstrate that embryos without Stella are compromised in preimplantation development and rarely reach the blastocyst stage. stella is thus one of few known mammalian maternal effect genes, as the phenotypic effect on embryonic development is mainly a consequence of the maternal stella mutant genotype. Furthermore, we show that STELLA that is expressed in human oocytes is also expressed in human pluripotent cells and in germ cell tumors. Interestingly, human chromosome 12p, which harbours STELLA, is consistently overrepresented in these tumors. These findings suggest a similar role for STELLA during early human development as in mice and a potential involvement in germ cell tumors.

The mitosis-specific monoclonal antibody MPM-2 recognizes phosphoproteins associated with the nuclear envelope in Chlamydomonas reinhardtii cells.

The monoclonal antibody MPM-2 recognizes a family of phosphorylated proteins present in mitotic cells. In a number of organisms it stains nuclei and also cytoskeletal structures which contain or organize tubulin. In mitotic Chlamydomonas reinhardtii cells MPM-2 reacts with phosphoproteins associated with the nuclear envelope (NE). Staining of the NE region appears in preprophase, reaches a maximum intensity in metaphase/anaphase and disappears rapidly in telophase. Localized hyperphosphorylation of the anterior NE region is apparent in many cells throughout mitosis. The distribution and timing of MPM-2 labeling suggests that in Chlamydomonas MPM-2 may be interacting with lamin-like phosphoproteins.

Prevalence of copper resistant salmonellae in India.

Sixty eight of 330 strains of Salmonella belonging to three different serotypes, S. typhi, S. typhimurium and S. bareilly, referred to at the National Salmonella and Escherichia Centre, Central Research Institute, Kasauli, between 1989-1991 were found to be copper resistant. Maximum number of strains (39.1%) were resistant in S. bareilly serotype, followed by S. typhimurium (21.7%) and least in S. typhi (17.4%). Of the 15 States/Union Territories (UTs) from where Salmonella strains were received, copper resistance was observed in strains from 10 States/UTs. This resistance was maximum among the strains from Goa (85.7%).

Transferable beta lactam resistance against cephalosporins in Salmonella typhimurium strains in India.

From 14 strains of S. typhimurium which were resistant to three cephalosporins (cephalexin, cefadroxil and sodium cefotaxime) the resistance plasmids were transferred to two different strains (Escherichia coli K12F-Lac-Rifr and S. typhimurium LT2). The plasmids were autotransferable and the donors as well as transconjugants showed high levels of MIC (80-320 micrograms/ml or more) against these antimicrobial agents. The resistance was demonstrated to be mediated by a 15 kilobase plasmid.

Increasing prevalence of high degree resistance amongst Salmonella to different antibiotics.

National Salmonella & Escherichia Centre situated at Central Research Institute, Kasauli receives Salmonella strains from all over the country. Eight hundred and fourteen Salmonella strains belonging to 14 serotypes received during 1986 were studied for antibiotic resistance and Minimum Inhibitory concentration (MIC) with regard to ampicillin (A), chloramphenicol (C), furazolidone (Fz) and gentamicin (G). Resistance to ampicillin was found to be highest (80%) and furazolidone the least (0.1%). Similarly a large number of strains (31%) had very high MIC values greater than 640 mcg per ml for chloramphenicol, whereas only 3.4% strains were found to have MIC values greater than 640 mcg per ml for gentamicin. The present findings have been discussed in the light of similar data published from this Centre earlier and from other sources in India.

Merit of mobilization technique in transfer of non-autotransferable R-plasmids.

A total of 200 urinary isolates of Esch.coli received at National Salmonella and Escherichia Centre, Central Research Institute, Kasauli during the years 1995 to 1997 were studied for transferable drug resistance. Out of 188 strains, 134 strains showing resistance to either Nalidixic acid or Rifampicin were subjected to autotransferable resistance studies. Of these 134 strains 131 showed either partial or enbloc transfer of R-factor. Mobilization experiment successfully transferred resistance marker in 14 of the 68 isolates in which resistance to one or more drugs could not be transferred during conjugation experiment.

Prevalance and resistance pattern of Salmonella serotypes in India.

During the period 1990-91, 3222 Salmonella strains were identified at the National Salmonella and Escherichia Centre (NSEC) at Central Research Institute, Kasauli. Of these, 2894 were from humans, 226 from poultry, 84 from animals and remaining 18 from reptiles, birds and other sources. These strains belonged to 53 different serotypes. These include 4 serotypes reported for the first time in India, namely S. kedogou, S. VP. bornheim, S. kisarawe and S. madras. Drug resistance studies revealed that 573 strains were sensitive to all the antibiotics commonly used, 1351 single drug resistant, 594 resistant to two drugs and 704 were multidrug resistant. One strain from human stool was resistant to all the antibiotics used. Prevalence of various Salmonella serotypes and their response to various drugs is discussed.

Adjuvant effect of DEAE-dextran and tetanus toxoid on whole cell heat inactivated phenol preserved typhoid vaccine.

Active mouse protection test (AMPT) and enzyme linked immunosorbent assay (ELISA) were used to determine the immunogenicity of whole cell typhoid vaccine when administered in conjunction with either tetanus toxoid (TT) or DEAE-Dextran (DD). Immunization of mice with whole cell typhoid vaccine showed enhanced potency either when administered in conjunction with TT or DD and values were statistically significant (p < 0.05) in comparison to conventional or standard typhoid vaccines. For ELISA, the mice were immunized with 2 different schedules, one in which a single dose of 0.25 ml subcutaneously (s/c) was administered and in another two doses of 0.25 ml each s/c, 14 days apart. In case of single dose schedule of immunization D vaccine (Whole cell typhoid + 5 mg/ml DD) showed significant increase of immune response (3.201 log10) as compared to plain vaccine (2.550 log10). Two dose schedule further increased the titres to 3.856 log10. DD adjuvanted vaccine showed higher potency by AMPT as compared to the TT adjuvanted vaccine or plain vaccine. The present study clearly demonstrates that a single dose of 0.25 ml which is equivalent to half of the conventionally used single human dose of typhoid vaccine adjuvanted with DD can significantly improve the immunogenicity of the vaccine.

MicroRNA in situ hybridization in tissue microarrays.

In situ hybridization is used to visualize nucleic acids in microscopic tissue sections and has in recent years been used successfully to detect microRNAs. We have further optimized a technique to detect and semiquantitatively assay microRNA expression in tissue microarrays derived from formalin-fixed paraffin-embedded archival tumor tissue.