Respiratory burst by dengue-virus-induced cytotoxic factor

This study investigates the induction and release of the superoxide anion (O- 2) and hydrogen peroxide (H2O2) by mouse spleen cells on stimulation with dengue type 2 virus (DV) and a DV-induced cytokine, the cytotoxic factor (mCF). Methods: Normal mice or their spleen cell cultures were inoculated with DV or mCF. At different time periods, the spleen cell supernatants were assayed for the production of O- 2 and H2O2. Results: Inoculation of DV in spleen cell cultures resulted in peak production of O- 2 and H2O2 at 48 and 72 h, respectively, while in DV-infected mouse spleen, the maximum production was on days 7 and 8, which correlated with the appearance of mCF in the milieu. Maximum O- 2 and H2O2 production occurred at 45 min and 1 h after inoculation of 5 µ g of mCF. Pretreatment of mCF with anti-mCF-antiserum inhibited O- 2 and H2O2 release indicating the specificity of the induction by mCF. The enriched subpopulations of macrophages and T cells produced O- 2 and H2O2 and not B cells. Treatment of the cells with superoxide dismutase increased H2O2 release but inhibited O- 2 release and the cytotoxicity in a dose-dependent manner. Conclusion: This showed that O- 2 is responsible for the cytotoxic activity of mCF and not H2O2. In conjunction with our earlier findings that pretreatment with NG-monomethyl-L-arginine inhibited mCF-induced production of NO and the cytotoxicity, it is concluded that the presence of both O- 2 and NO is required for the cytotoxic activity of mCF, thereby indicating a possible role of peroxynitrite

An Indian hospital study of viral causes of acute respiratory infection in children

From Sept. 1986 to Jan. 1989, a hospital-based study was conducted on 736 children, under 5 years of age, with acute respiratory infection. Nasopharyngeal secretions were examined for viruses by culture and by immunofluorescence. Viruses were detected in 22% of specimens: respiratory syncytial (5%), parainfluenza (5%), influenza A (4%), influenza B (2%), adenovirus (3%), measles (3%). The highest rates of detection were with patients diagnosed clinically as pneumonia or upper respiratory tract infection. The case fatality rate was very high (43%) in children with measles virus infection

Cytotoxic factor in dengue haemorrhagic fever

Objective: Cytotoxic factor is a unique pathogenesis-associated cytokine that is produced in mice (mCF) and man (hCF) during dengue virus infection. This study was undertaken to investigate the prevalence of hCF and its relationship to the duration and severity of the illness, and to ascertain its role, if any, in the pathogenesis of dengue fever (DF) and dengue haemorrhagic fever (DHF). Methods: Peripheral venous blood was collected from the patients of various grades and on different days after the onset of clinical illness. Sera were collected from a total of 333 cases, and analysed for the presence of hCF by inhibition ELISA and dot blot tests. Result: The positivity for hCF was 100% in cases of DHF grades III and IV, while overall positivity was seen in 295 out of 333 (88%) cases studied. Sera collected from the 1st to the 20th day of illness were positive for hCF. This was not seen at later periods. A majority of cases (52%) were below 15 years of age and peak positivity of 96% was noticed in the age-group of 11-15 years. The mean inhibition value of the ELISA was lowest (40 ± 8%) in cases of DF and was highest (70 ± 10%) in DHF grade IV, and the peak titres were found on the first 4 days of the illness. Conclusion: The findings show the presence of hCF in the majority of cases. It is detectable up to the 20th day of illness and may suggest an association of higher levels of hCF with the onset and severity of the illness

Viral aetiology of acute respiratory infections in children in North India

Two hundred and thirty children clinically diagnosed as suffering from acute respiratory infection were tested for four major groups of viral aetiological agents, i.e. influenza para-influenza, respiratory syncytial virus (RSV) and adenoviruses using indirect immunofluorescence technique. At least one of the respiratory viruses was identified in 51 (22 per cent) specimens, which included influenza A in 6 (3 per cent), influenza B in 3 (1 per cent), para-influenza type 1 in 3 (1 per cent), para-influenza type 3 in 13 (6 per cent), RSV in 11 (5 per cent) adenovirus in 12 (5 per cent), and dual virus infections in 3 (1 per cent) cases. Maximum number of virus identification was noted in children below 1 year of age, particularly infection with RSV followed by para-influenza and adenoviruses. Value of rapid diagnosis by indirect immunofluorescence technique is stressed

Quantum damping of position due to energy measurements

Quantum theory for measurements of energy is introduced and its consequences for the average position of monitored dynamical systems are analyzed. It turns out that energy measurements lead to a localization of the expectation values of other observables. This is manifested, in the case of position, as a damping of the motion without classical analogue. Quantum damping of position for an atom bouncing on a reflecting surface in presence of a homogeneous gravitational field is dealt in detail and the connection with an experiment already performed in the classical regime is studied. We show that quantum damping is testable provided that the same measurement strength obtained in the experimental verification of the quantum Zeno effect in atomic spectroscopy [W. M. Itano et al., Phys. Rev. A {\bf 41}, 2295 (1990)] is made available.Comment: 19 pages + 4 figures available upon request; Plain REVTeX; To be published in Phys. Rev.

Recurrent De Novo NAHR Reciprocal Duplications in the ATAD3 Gene Cluster Cause a Neurogenetic Trait with Perturbed Cholesterol and Mitochondrial Metabolism.

Recent studies have identified both recessive and dominant forms of mitochondrial disease that result from ATAD3A variants. The recessive form includes subjects with biallelic deletions mediated by non-allelic homologous recombination. We report five unrelated neonates with a lethal metabolic disorder characterized by cardiomyopathy, corneal opacities, encephalopathy, hypotonia, and seizures in whom a monoallelic reciprocal duplication at the ATAD3 locus was identified. Analysis of the breakpoint junction fragment indicated that these 67 kb heterozygous duplications were likely mediated by non-allelic homologous recombination at regions of high sequence identity in ATAD3A exon 11 and ATAD3C exon 7. At the recombinant junction, the duplication allele produces a fusion gene derived from ATAD3A and ATAD3C, the protein product of which lacks key functional residues. Analysis of fibroblasts derived from two affected individuals shows that the fusion gene product is expressed and stable. These cells display perturbed cholesterol and mitochondrial DNA organization similar to that observed for individuals with severe ATAD3A deficiency. We hypothesize that the fusion protein acts through a dominant-negative mechanism to cause this fatal mitochondrial disorder. Our data delineate a molecular diagnosis for this disorder, extend the clinical spectrum associated with structural variation at the ATAD3 locus, and identify a third mutational mechanism for ATAD3 gene cluster variants. These results further affirm structural variant mutagenesis mechanisms in sporadic disease traits, emphasize the importance of copy number analysis in molecular genomic diagnosis, and highlight some of the challenges of detecting and interpreting clinically relevant rare gene rearrangements from next-generation sequencing data

Lower cardiorespiratory fitness contributes to increased insulin resistance and fasting glycaemia in middle-aged South Asian compared with European men living in the UK

AIMS/HYPOTHESIS: This study aimed to determine the extent to which increased insulin resistance and fasting glycaemia in South Asian men, compared with white European men, living in the UK, was due to lower cardiorespiratory fitness (maximal oxygen uptake [[Formula: see text]]) and physical activity. METHODS: One hundred South Asian and 100 age- and BMI-matched European men without diagnosed diabetes, aged 40–70 years, had fasted blood taken for measurement of glucose concentration, HOMA-estimated insulin resistance (HOMA(IR)), plus other risk factors, and underwent assessment of physical activity (using accelerometry), [Formula: see text], body size and composition, and demographic and other lifestyle factors. For 13 South Asian and one European man, HbA(1c) levels were >6.5% (>48 mmol/mol), indicating potential undiagnosed diabetes; these men were excluded from the analyses. Linear regression models were used to determine the extent to which body size and composition, fitness and physical activity variables explained differences in HOMA(IR) and fasting glucose between South Asian and European men. RESULTS: HOMA(IR) and fasting glucose were 67% (p < 0.001) and 3% (p < 0.018) higher, respectively, in South Asians than Europeans. Lower [Formula: see text], lower physical activity and greater total adiposity in South Asians individually explained 68% (95% CI 45%, 91%), 29% (11%, 46%) and 52% (30%, 80%), respectively, and together explained 83% (50%, 119%) (all p < 0.001) of the ethnic difference in HOMA(IR). Lower [Formula: see text] and greater total adiposity, respectively, explained 61% (9%, 111%) and 39% (9%, 76%) (combined effect 63% [8%, 115%]; all p < 0.05) of the ethnic difference in fasting glucose. CONCLUSIONS/INTERPRETATION: Lower cardiorespiratory fitness is a key factor associated with the excess insulin resistance and fasting glycaemia in middle-aged South Asian, compared with European, men living in the UK. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00125-013-2969-y) contains peer-reviewed but unedited supplementary material, which is available to authorised users

Resonances in a two-dimensional electron waveguide with a single delta-function scatterer

We study the conductance properties of a straight two-dimensional electron waveguide with an s-like scatterer modeled by a single delta-function potential with a finite number of modes. Even such a simple system exhibits interesting resonance phenomena. These resonances are explained in terms of quasi-bound states both by using a direct solution of the Schroedinger equation and by studying the Green's function of the system. Using the Green's function we calculate the survival probability as well as the power absorption and show the influence of the quasi-bound states on these two quantities.Comment: 5 pages, 6 figures, to be published in Physical Review

UK informative inventory report (1990 to 2013)

This is the 10th Informative Inventory Report (IIR) from the UK National Atmospheric Emissions Inventory (NAEI) Programme. The report is compiled to accompany the UK’s 2015 data submission under the United Nations Economic Commission for Europe (UNECE) Convention on Long-Range Transboundary Air Pollution (CLRTAP) and contains detailed information on annual emission estimates of air quality pollutants by source in the UK from 1990 onwards