Outbreak of tuberculosis caused by Mycobacterium bovis in golden Guernsey goats in Great Britain

An outbreak of caprine tuberculosis caused by Mycobacterium bovis was disclosed in June 2008, affecting goats of the golden Guernsey breed kept on 10 separate smallholdings in south-west Wales and the west of England. Following the initial diagnosis at postmortem examination, 30 goats that reacted positively to the single intradermal comparative cervical tuberculin (SICCT) test, together with five in-contact animals, were euthanased and subjected to postmortem examination and mycobacterial culture. Spoligotyping and variable number tandem repeat analysis of isolates showed that they were all of the same genotype, endemic to south-west Wales. Retrospective movement tracings identified a goat herd in south-west Wales, by then completely dispersed, as the probable common source of infection. There was a perfect correlation between the SICCT test and culture results in all slaughtered goats. Grossly visible tubercular lesions were observed at postmortem examination in all but one reactor.

Elastic constants of fibre-textured thin films determined by X-ray diffraction

A new methodology is presented that allows the rapid determination of elastic constants of cubic fibre-textured thin films by X-ray diffraction. The theoretical concept is developed and tested on calculated examples of Cu and CrN films. The mechanical elastic constants are extrapolated from X-ray elastic constants by taking into consideration crystal and macroscopic elastic anisotropy. The derived algorithm enables the determination of a reflection and the corresponding value of the X-ray anisotropic factor Γ for which the X-ray elastic constants are equal to their mechanical counterparts in the case of fibre-textured cubic polycrystalline aggregates. The approach is independent of the crystal elastic anisotropy and depends on the fibre-texture type, the texture sharpness, the number of randomly oriented crystallites and the supposed grain-interaction model. In the experimental part, out-of-plane Young's moduli of 111 and 311 fibre-textured Cu and CrN thin films deposited on monocrystalline Si(100) substrates are determined. The moduli are extrapolated from thin-film experimental X-ray elastic constants that are determined by a combination of X-ray diffraction substrate curvature and sin(2)ψ methods. For the calculation, the film macroscopic elastic anisotropy (texture) is considered. The advantage of the new technique lies in the fact that experimental moduli are determined nondestructively, using a static diffraction experiment, and represent volume-averaged quantities.

Evaluation of an enzyme-linked immunosorbent assay for detection of antibodies to Fasciola hepatica in milk

Antibodies against Fasciola hepatica were detected in serum and individual milk samples of dairy cattle using an ELISA. Percentage positivity (PP) values in milk samples were related to serum PP values and were not influenced by days into lactation. The correlation coefficient between serum and individual milk samples was highly significant (r=0.84, P<0.005). The correlation coefficient between herd seroprevalence and herd milk antibody prevalence was 0.96. The correlation coefficient between prevalence measured by faecal egg count and both seroprevalence and milk antibody prevalence within the herd was 0.87. The diagnostic sensitivity and specificity for milk were 92% (95% CI=89-96) and 88% (95% CI=85-91), respectively, when the serum test was considered as a gold standard. In conclusion, the level of antibody to F. hepatica in milk is significantly correlated with the antibody level in serum and this ELISA is suitable as a means of routine veterinary diagnosis of exposure to F. hepatica in cattle and an alternative to testing sera.

High-temperature residual stresses in thin films characterized by x-ray diffraction substrate curvature method

A new x-ray technique to determine temperature dependencies of macroscopic stresses in thin films by characterizing the substrate curvature is introduced. The technique is demonstrated on polycrystalline TiN and Al thin films deposited on Si(100) wafers. The structures are thermally cycled in the temperature range of 25-400 degrees C using a newly developed heating chamber attached to a commercial x-ray diffractometer. The curvature of the freestanding samples was determined by the rocking curve measurement of substrate Si 400 reflections at different lateral positions of the samples, and the stresses are calculated using Stoney's formula. The results show that the magnitude of the stress is in good agreement with the results obtained by other techniques. For the practical application of the technique, the sample mounting and the temperature control are of great importance.

Prevalence of symptoms of childhood asthma, allergic rhinoconjunctivitis and eczema in the Pacific: the International Study of Asthma and Allergies in Childhood (ISAAC)

The International Study of Asthma and Allergies in Childhood (ISAAC) has provided valuable information regarding international prevalence patterns and potential risk factors for asthma, allergic rhinoconjunctivitis and eczema. However, the only Pacific countries that participated in ISAAC Phase I were Australia and New Zealand, and these included only a small number of Pacific children. Phase III has involved not only repeating the Phase I survey to examine time trends, but also to include centres and countries which are of interest but did not participate in Phase I. The ISAAC Phase III study was therefore conducted in the Pacific (in French Polynesia, New Caledonia, Tonga, Fiji Islands, Samoa, Cook Islands, Tokelau Islands and Niue). The overall prevalence rates of current symptoms (in the last 12 months) were 9.9% for asthma, 16.4% for allergic rhinoconjunctivitis and 10.7% for atopic eczema. The prevalence of current wheezing (9.9%) was generally much lower than that has been observed in Pacific children in New Zealand (31%), but there was considerable variation between the various Pacific centres: Tokelau Islands (19.7%), Tonga (16.2%), Niue (12.7%), French Polynesia (11.3%), Cook Islands (10.6%), Fiji Islands (10.4%), New Caledonia (8.2%) and Samoa (5.8%). The reasons for these differences in prevalence across the Pacific are unclear and require further research. The finding that prevalence levels are generally considerably lower than those in Pacific children in New Zealand adds to previous evidence that children who migrate experience an altered risk of asthma as a result of exposure to a new environment during childhood.

Rapid determination of stress factors and absolute residual stresses in thin films

A methodology is presented that allows the determination of experimental stress factors in thin films on the basis of static diffraction measurements. The approach relies on the characterization of thin films deposited on a monocrystalline substrate serving as a mechanical sensor. Rocking-curve measurements of the symmetrical reflections of the substrate are used to determine the substrate curvature and subsequently the macroscopic stress imposed on the film. The elastic strain in the film is determined by lattice-spacing measurement at different sample tilt angles. The calculated experimental stress factors are applied to thin films deposited on other types of substrates and are used to determine the absolute magnitude of the residual stress. The approach is applied to nanocrystalline TiN and CrN thin films deposited on Si(100) and steel substrates, characterized using a laboratory-type θ/θ goniometer.

Parotid TB

TB of the parotid is rare and only about 100 cases have been reported in the world literature. Often the diagnosis is made only after the surgery performed for a suspected neoplasm. We describe three patients with diffuse form of parotidTB without any evidence of tubercular focus elsewhere. Fine needle aspiration cytology confirmed the diagnosis in two cases, while the third case was diagnosed only after surgery.

Complete heart block following occlusion of the first septal perforator after coronary stenting

We report a case of transient complete heart block following occlusion of the first septal perforator branch after stent deployment in the left anterior descending coronary artery. The patient was treated with temporary transvenous pacing and reverted spontaneously to normal atrioventricular conduction after 3 days.

Human papillomavirus, p53 and cyclin D1 expression in oropharyngeal carcinoma

Forty-two specimens from oropharyngeal (tonsil and base of tongue) squamous cell carcinoma patients (SCC) were studied for presence of HPV 16 by in situ hybridization and by immunohistochemistry for p53 and Cyclin D1 protein overexpression. Thirty-one per cent of cases were HPV-16 positive, which correlates with the prevalence reported worldwide. 74% of cases showed p53 protein overexpression and 79% showed Cyclin D1 overexpression. There was no correlation between HPV status and either p53 or Cyclin D1 overexpression (P>0.05). These three variables also did not correlate with factors such as grade of the tumour, stage of the disease or lymph nodal metastasis at presentation.

Characterization of a naphthalene derivative inhibitor of retroviral integrases

The retroviral integrase protein (IN) is essential for virus replication and, therefore, an attractive target for the development of inhibitors to treat human immunodeficiency virus (HIV) infection. Diverse classes of compounds that are active against this protein have been discovered using in vitro assays. Here we describe the synthesis of a novel compound, 3,8-dibromo-7-amino-4-hydroxy-2-naphthalenesulfonic acid (2BrNSA), which inhibits the in vitro activities of the full-length HIV-1 and avian sarcoma virus (ASV) integrases, and the isolated catalytic core fragment of the ASV protein (residues 52-207). The compound also inhibits retroviral reverse transcriptase in vitro, but the IC(50) for the HIV-1 enzyme is almost two orders of magnitude higher than for HIV-1 integrase. The inhibitor was found to be active in cell culture, preventing reporter gene transduction of HeLa cells by both ASV and HIV-1 vectors. Neither viral attachment nor uptake into cells appeared to be affected in these transfections, whereas accumulation of vector DNA and its joining to host DNA were both drastically reduced in the presence of the inhibitor. Propagation of two different strains of replication-competent HIV-1 in human peripheral blood mononuclear cells (PBMCs) was also reduced by the inhibitor, allowing survival of a substantial number of cells in the treated cultures. Based on these and other results we speculate that binding of 2BrNSA to integrase in infected cells interferes not only with its catalytic activity but also with critical interactions that are required for the formation or function of the reverse transcriptase complex. Its activity in cell culture suggests that this inhibitor may provide a valuable new lead for further development of drugs that target early steps in the HIV life cycle.

Human papillomavirus, p53 and cyclin D1 expression in oropharyngeal carcinoma

Forty-two specimens from oropharyngeal (tonsil and base of tongue) squamous cell carcinoma patients (SCC) were studied for presence of HPV 16 by in situ hybridization and by immunohistochemistry for p53 and Cyclin D1 protein overexpression. Thirty-one per cent of cases were HPV-16 positive, which correlates with the prevalence reported worldwide. 74% of cases showed p53 protein overexpression and 79% showed Cyclin D1 overexpression. There was no correlation between HPV status and either p53 or Cyclin D1 overexpression (P>0.05). These three variables also did not correlate with factors such as grade of the tumour, stage of the disease or lymph nodal metastasis at presentation.

Capillary electrophoresis determination of the binding affinity of bioactive sulfated polysaccharides to proteins: study of the binding properties of fucoidan to antithrombin

The interaction of proteins with polysaccharides represents a major and challenging topic in glycobiology, since such complexes mediate fundamental biological mechanisms. An affinity capillary electrophoresis method has been developed to evidence the complex formation and to determine the binding properties between an anticoagulant polysaccharide of marine origin, fucoidan, and a potential target protein, antithrombin. This method is a variant of zonal electrophoresis in the mobility shift format. A fixed amount of protein was injected into a capillary filled with a background electrolyte containing the polysaccharide in varying concentrations. The effective mobility data of the protein were processed according to classical linearization treatments to obtain the binding constant for the polysaccharide/antithrombin complex. The results indicate that fucoidan binds to antithrombin in a 1:1 stoichiometry and with an affinity depending on the molecular weight of the polysaccharide. For heparin, the binding constant obtained similarly is in accordance with the literature. This is the first report showing the implementation of a capillary electrophoresis method contributing to the mechanistic understanding of the biological activities of fucoidan and providing evidence for the complex formation between fucoidan and the protein inhibitor of the coagulation antithrombin.

Epidemiological changes in hepatitis C virus genotypes in France: evidence in intravenous drug users

Hepatitis C virus (HCV) genotypes are distributed differently depending on geography and route of infection. We characterized the distribution of genotypes in a large cohort of patients with chronic hepatitis C in the South-east of France and evaluated the relative prevalence according to time of acquisition. One thousand, one hundred-and-eighty-three patients who were anti-HCV-positive were studied. HCV genotype distribution has changed significantly from the 1960s to 2000. The prevalence of genotype 1b decreased from 47% before 1978 to 18.8% in the 1990s while the prevalence of genotype 1a and 3a increased during the same period from 18% and 15.3% to 28.8% and 26.3%, respectively. The logistic regression model showed that genotype 1a was significantly more common in patients infected through intravenous drug injection odds ratio ((OR): 2.08, P < 0.01) and after 1990 (OR: 1.98, P < 0.05). Genotype 1b was significantly less frequent in patients infected through intravenous drug injection (OR: 0.17, P < 0.001) and has decreased since 1978 (OR: 0.27, P < 0.001). Genotype 3a was independently associated with intravenous drug injection (OR: 6.1, P < 0.001) and tattooing (OR: 8.01, P < 0.001) and was more frequent in the 1979-90 period (OR: 2.05 and 1.74, P < 0.001 and P < 0.05). Our results show a modification of HCV genotypes distribution over the last four decades due to an increase of intravenous drug use (IVDU) contamination and an evolution of HCV genotypes distribution only in IVDU population characterized by a decrease of genotype 1b, an increase of genotype 3a from 1970 to 1990 and a higher increase of genotype 1a which is currently the predominant genotype in our population.

Two essential DNA polymerases at the bacterial replication fork

DNA replication in bacteria is carried out by a multiprotein complex, which is thought to contain only one essential DNA polymerase, specified by the dnaE gene in Escherichia coli and the polC gene in Bacillus subtilis. Bacillus subtilis genome analysis has revealed another DNA polymerase gene, dnaE(BS), which is homologous to dnaE. We show that, in B. subtilis, dnaE(BS) is essential for cell viability and for the elongation step of DNA replication, as is polC, and we conclude that there are two different essential DNA polymerases at the replication fork of B. subtilis, as was previously observed in eukaryotes. dnaE(BS) appears to be involved in the synthesis of the lagging DNA strand and to be associated with the replication factory, which suggests that two different polymerases carry out synthesis of the two DNA strands in B. subtilis and in many other bacteria that contain both polC and dnaE genes.

Screening of environmental DNA libraries for the presence of genes conferring Na(+)(Li(+))/H(+) antiporter activity on Escherichia coli: characterization of the recovered genes and the corresponding gene products

Environmental DNA libraries prepared from three different soils were screened for genes conferring Na(+)(Li(+))/H(+) antiporter activity on the antiporter-deficient Escherichia coli strain KNabc. The presence of those genes was verified on selective LK agar containing 7.5 mM LiCl. Two positive E. coli clones were obtained during the initial screening of 1,480,000 recombinant E. coli strains. Both clones harbored a plasmid (pAM1 and pAM3) that conferred a stable Li(+)-resistant phenotype. The insert of pAM2 (1,886 bp) derived from pAM1 contained a gene (1,185 bp) which encodes a novel Na(+)/H(+) antiporter belonging to the NhaA family. The insert of pAM3 harbored the DNA region of E. coli K-12 containing nhaA, nhaR, and gef. This region is flanked by highly conserved insertion elements. The sequence identity with E. coli decreased significantly outside of the insertion sequence elements, indicating that the unknown organism from which the insert of pAM3 was cloned is different from E. coli. The products of the antiporter genes located on pAM2 and pAM3 revealed functional homology to NhaA of E. coli and enabled the antiporter-deficient E. coli mutant to grow on solid media in the presence of up to 450 mM NaCl or 250 mM LiCl at pH 8.0. The Na(+)/H(+) antiporter activity in everted membrane vesicles that were derived from the E. coli strains KNabc/pAM2 and KNabc/pAM3 showed a substantial increase between pHs 7 and 8.5. The maximal activity was observed at pHs 8.3 and 8.6, respectively. The K(m) values of both antiporters for Na(+) were approximately 10-fold higher than the values for Li(+).

Regioselective desulfation of sulfated L-fucopyranoside by a new sulfoesterase from the marine mollusk Pecten maximus: application to the structural study of algal fucoidan (Ascophyllum nodosum)

The study of the structural bases of the biological properties of algal fucoidan (Ascophyllum nodosum) led us to look for enzymes able to modify this sulfated polysaccharide. In this context, we found a sulfoesterase activity in the digestive glands of the common marine mollusk Pecten maximus, which is active on fucoidan. This sulfoesterase activity was shown by capillary electrophoresis and 13C-1H NMR (500 MHz) analysis of the enzymatic hydrolysis of the fucoidan, of fucoidan oligosaccharides and of sulfated fucose isomers. We report the exhaustive list of all proton and carbon chemical shifts for each of the three isomers of sulfated-l-fucose (including of their alpha/beta anomers), i.e. the 2-O-, 3-O- and 4-O-sulfated fucose, which have been useful reference values for the assignments of NMR spectra of fucoidan oligosaccharides upon enzymatic desulfation. Our results demonstrated a high regioselectivity for this sulfoesterase, which hydrolyzes only the sulfate group at the 2-O position of the fucopyranoside. Therefore, this sulfoesterase is a helpful tool in the structure-activity study of the fucoidan, as the literature data suggest that the 2-O-sulfation level play a central role in the biological properties of the polysaccharide.

Evaluation of use of a single intravaginal swab to detect multiple sexually transmitted infections in active-duty military women

The accuracy and suitability of use of a single intravaginal swab (SIS) for polymerase chain reaction detection of Neisseria gonorrhoeae, Chlamydia trachomatis, Trichomonas vaginalis, and human papillomavirus infection was assessed in a cross-sectional study of 841 active-duty military women. The SIS, compared with standard diagnostic tests, allowed detection of more gonorrhea, more chlamydial infection, and more trichomoniasis. Sensitivity and specificity of SIS detection compared with adjudicated true-positive diagnoses were 95.8% and 97.8%, respectively, for gonorrhea, 94.6% and 99.3% for chlamydial infection, and 92.2% and 98.2% for trichomonal infection. Results with SISs were comparable to those with cervical swabs tested for human papillomavirus. Assay of clinician-collected and self-collected SISs yielded prevalences similar to those of standard diagnostic tests for all sexually transmitted infections. Therefore, the use of SISs is acceptable for the simultaneous diagnosis of multiple sexually transmitted infections and has potential for use as a self-administered diagnostic tool with widespread applicability among women.