1,781 research outputs found

    Importance of determining viability of Mycobacterium leprae inside macrophages-anin vitro method using uracil

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    It has been demonstrated thatMycobacterium leprae, are caPable of taking uP uracil and incorPorating it into trichloroacetic acid-insoluble materials, both as free susPension of bacteria, as well as when they are inside the macrophages, a host cell for theirin vivo survival. Same amount of bacteria show better incorPoration inside macroPhages than as free bacterial susPension. Both tyPes of incorPoration are inhibited by rifamPicin an antileProsy drug and an RNA synthesis inhibitor. Thus uracil uPtake byMycobacterium lePrae inside macroPhages has been used for standardising a raPidin vitro viability assay for the leProsy causing bacteria

    Evidence for massive bulk Dirac Fermions in Pb1x_{1-x}Snx_xSe from Nernst and thermopower experiments

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    The lead chalcogenides (Pb,Sn)Te and (Pb,Sn)Se are the first examples of topological crystalline insulators (TCI) predicted \cite{Fu,Hsieh} (and confirmed \cite{Hasan,Story,Takahashi}) to display topological surface Dirac states (SDS) that are protected by mirror symmetry. A starting premise \cite{Hsieh} is that the SDS arise from bulk states describable as massive Dirac states \cite{Wallis,Svane}, but this assumption is untested. Here we show that the thermoelectric response of the bulk states display features specific to the Dirac spectrum. We show that, in the quantum limit, the lowest Landau Level (LL) is singly spin-degenerate, whereas higher levels are doubly degenerate. The abrupt change in spin degeneracy leads to a large step-decrease in the thermopower SxxS_{xx}. In the lowest LL, SxxS_{xx} displays a striking linear increase vs. magnetic field. In addition, the Nernst signal undergoes an anomalous sign change when the bulk gap inverts at 180 K.Comment: 16 pages, 8 figure

    Effect of strain on stripe phases in the Quantum Hall regime

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    Spontaneous breaking of rotational symmetry and preferential orientation of stripe phases in the quantum Hall regime has attracted considerable experimental and theoretical effort over the last decade. We demonstrate experimentally and theoretically that the direction of high and low resistance of the two-dimensional (2D) hole gas in the quantum Hall regime can be controlled by an external strain. Depending on the sign of the in-plane shear strain, the Hartree-Fock energy of holes or electrons is minimized when the charge density wave (CDW) is oriented along [110] or [1-10] directions. We suggest that shear strains due to internal electric fields in the growth direction are responsible for the observed orientation of CDW in pristine electron and hole samples.Comment: 10 pages, 3 figure

    Quark Mass Corrections to the Perturbative Thrust and its Effect on the determination of αs\alpha_s

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    We consider the effects of quark masses to the perturbative thrust in e+ee^+e^- annihilation. In particular we show that perturbative power corrections resulting from non-zero quark masses considerably alters the size of the non-perturbative power corrections and consequently, significantly changes the fitted value of αs\alpha_s.Comment: Latex, 6 pages, 2 figures, minor change in text, added one referenc

    Specific human leukocyte antigen DQ influence on expression of antiislet autoantibodies and progression to type 1 diabetes

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    Human leukocyte antigen (HLA) DQ haplotypes have the strongest genetic association with type 1 diabetes (T1DM) risk. OBJECTIVE: The objective of the study was to analyze whether HLA DQ alleles influence the development of antiislet autoantibodies, the progression to T1DM among autoantibody-positive relatives, or both. DESIGN: The Diabetes Prevention Trial-1 screened more than 90,000 nondiabetic relatives of patients for cytoplasmic islet-cell autoantibody (ICA) expression between 1994 and 2002. SETTING: The study was conducted in the general community. PARTICIPANTS: The Diabetes Prevention Trial-1 found 2817 ICA-positive relatives who were tested for biochemical autoantibodies (GAD65, ICA512, and insulin) and HLA-DQ haplotypes, and 2796 of them were followed up for progression to diabetes for up to 8 yr (median, 3.6 yr). MAIN OUTCOME MEASURE: Progression to T1DM was measured. RESULTS: High-risk DQ haplotypes and genotypes were associated with a higher percentage of relatives expressing multiple biochemical autoantibodies and higher T1DM risk (e.g., respectively, 59 and 36% at 5 yr for carriers of the DQA1*0301-DQB1*0302/DQA1*0501-DQB1*0201 genotype). The number of autoantibodies expressed significantly increased T1DM risk and across different DQ genotypes, autoantibody positivity directly correlated with diabetes risk. However, multivariate analyses indicated that the influence of most genotypes on T1DM risk was not independent from autoantibody expression, with the possible exception of DQA1*0102-DQB1*0602. Specific genotypic combinations conferred 5-yr diabetes risks significantly lower (e.g. 7%-DQA1*0201-DQB1*0201/DQA1*0501-DQB1*0201 and 14%-DQA1*0301-DQB1*0301/DQA1*0501-DQB1*0201) than when those haplotypes were found in other combinations. CONCLUSION: HLA DQ alleles determine autoantibody expression, which is correlated with diabetes progression. Among autoantibody-positive relatives, most HLA DQ genotypes did not further influence T1DM risk

    HLA-DRB1*15:01-DQA1*01:02-DQB1*06:02 Haplotype Protects Autoantibody-Positive Relatives From Type 1 Diabetes Throughout the Stages of Disease Progression

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    The HLA-DRB1*15:01-DQA1*01:02-DQB1*06:02 haplotype is linked to protection from the development of type 1 diabetes (T1D). However, it is not known at which stages in the natural history of T1D development this haplotype affords protection. We examined a cohort of 3,358 autoantibody-positive relatives of T1D patients in the Pathway to Prevention (PTP) Study of the Type 1 Diabetes TrialNet. The PTP study examines risk factors for T1D and disease progression in relatives. HLA typing revealed that 155 relatives carried this protective haplotype. A comparison with 60 autoantibody-negative relatives suggested protection from autoantibody development. Moreover, the relatives with DRB1*15:01-DQA1*01:02-DQB1*06:02 less frequently expressed autoantibodies associated with higher T1D risk, were less likely to have multiple autoantibodies at baseline, and rarely converted from single to multiple autoantibody positivity on follow-up. These relatives also had lower frequencies of metabolic abnormalities at baseline and exhibited no overall metabolic worsening on follow-up. Ultimately, they had a very low 5-year cumulative incidence of T1D. In conclusion, the protective influence of DRB1*15:01-DQA1*01:02-DQB1*06:02 spans from autoantibody development through all stages of progression, and relatives with this allele only rarely develop T1D

    BULLOUS PEMPHIGOID A RARE AUTOIMMUNE DISEASE: A CASE REPORT

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    Background. Bullous pemphigoid (BP) is a rare autoimmune blistering skin disease in the elderly and it is manifested by cutaneous blisters on the skin lesions. The objective was to emphasize the rare case of BP. Methods. A case report of BP in a 58-year-old male patient admitted to a dermatology ward is presented. Results. A 58-year-old male patient with complaints of fluid-filled skin lesions, was examined initially over the trunk, gradually progressed involving B/L upper and lower extremities. Even though the patient was treated with the recommended therapy of corticosteroid (Dexamethasone) along with adjuvant drugs, new skin lesions continued to develop, and the patient’s condition worsened. The Prednisolone was started in place of Dexamethasone on the fifth day of treatment at its higher dose (50mg/day), the Prednisolone proved its efficacy to combat the extensive condition of BP. Conclusions. Bullous pemphigoid is a distressing blistering skin disease. Untreated disease is often fatal because of the susceptibility to infection and fluid-electrolyte disturbances. The mortality of patients with bullous pemphigoid has been significantly reduced with the advent of new therapies and treatment modalities. The treatment with systemic and topical corticosteroids forms the mainstay of treatment along with other adjuvant drugs. In the present case study, the use of Prednisolone has proven its efficacy in the extensive disease state of BP and improved the patient’s quality of life
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