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The current dependence of the excess conductivity is measured up to ≃3Tc for a Bi2Sr2CuO6+δ thin film, as a function of doping. It is found to be anomalously sensitive to the transport current and to behave as a universal function of T/Tc in the whole doping range. We discuss these results in the perspective of a granular superconductor with a gapless-like behavior. [ABSTRACT FROM AUTHOR]

Background: Community-associated Clostridium difficile infection is inconsistently associated with antibiotic exposure. This study uses a self-controlled case series (SCCS) design to estimate antibiotic exposure effect sizes and compare them with those estimated from previous case-control studies., Methods: We estimated the association between antibiotic exposure and community-associated Clostridium difficile infection among 139,000 patients registered to the Barrie Family Health Team from January 1, 2011, to May 1, 2017, using an SCCS design. Poisson regression analysis was used to estimate the incidence rate ratio (IRR) between antibiotic exposure versus nonexposure periods within individuals. Antibiotic exposure was categorized as either high risk (fluoroquinolone, clindamycin, or cephalosporin) or low risk (all other antibiotic classes)., Results: The final analysis included 189 cases. The pooled IRR for high-risk antibiotics was 2.26 (95% confidence interval [CI] 1.29, 3.98) and 2.03 (95% CI 1.19, 3.47) for lower-risk antibiotics. There was no difference between high-risk and lower-risk antibiotics (IRR 1.11, 95% CI 0.53, 2.36)., Interpretation: The IRRs were smaller than the odds ratios reported in previous case-control studies, suggesting a less biased estimate because SCCS designs control for time-invariant confounders. Compared with case-control studies, SCCS designs are underused in infection prevention and control studies., (Copyright © 2019 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.)

A 4 1/2-month-old infant had three separate episodes of invasive Haemophilus influenzae type b infection and did not produce antibody to the capsular polysaccharide of H influenzae b. Immunologic evaluation disclosed normal immunoglobulin and complement concentrations and normal T-cell number and function. In view of the persistent presence of type-specific capsular polysaccharide of H influenzae b (polyribophosphate [PRP]) in blood serum without any detectable anti-PRP antibody for 30 days following H influenzae b meningitis, monthly treatment with immune human serum globulin was undertaken until spontaneous production of anti-PRP antibody occurred. The patient's 4-year-old sibling was found to be a nasopharyngeal carrier and may have been a source for reinfection. A search for possible family carriers should be conducted in evaluating the conditions of patients with recurrent invasive H influenzae b infection. In addition, temporary treatment with immune human serum globulin should be considered.

The aim of these studies was to determine whether unresponsiveness to the main determinant of penicillin, benzylpenicilloyl, can be induced in human peripheral lymphocytes in vitro by conjugates of benzylpenicilloyl (BPO) autologous gamma globulin (HGG). Initially it was shown that conjugates of BPO-keyhole limpet hemocyanin (KLH) elicited lymphocyte proliferation in the peripheral blood lymphocytes of six out of nine adult individuals in vitro. In contrast, conjugates of dinitrophenylated KLH and of BPO-HGG and the carriers HGG and KLH alone failed to do so. Similarly, release of the non-specific helper factor, lymphocyte mitogenic factor (LMF) occurred only after BPO-KLH stimulation. LMF activity was measured by B-cell proliferation and incorporation of radioactive amino acids into secreted immunoglobulin. Treatment with BPO-HGG for 24 h in vitro inhibited BPO-KLH-induced lymphocyte proliferation and LMF release. Treatment with either HGG, dinitrophenylated HGG, BPO-KLH, or BPO-human serum albumin failed to abrogate T-cell lymphocyte proliferation of human lymphocytes in vitro. The antigen specificity of the reduced immunologic responsiveness was further demonstrated by the observation that lymphocytes treated with BPO-HGG for 24 h in vitro responded normally to tetanus toxoid antigen.The data suggest that conjugates of BPO-HGG induce hapten-specific helper T-cell unresponsiveness in vitro.

A new syndrome of acquired immunodeficiency has been identified in seven children who were small for gestational age at birth and subsequently have exhibited failure to thrive, lymphadenopathy, parotitis, hepatosplenomegaly, interstitial pneumonia, and recurrent infections. All have a profound cell-mediated immunodeficiency with reversed T4/T8 ratios. Six are hypergammaglobulinemic and one has low IgG levels. The mothers of five of the seven children are sexually promiscuous and/or drug addicts. Three mothers have an immunodeficiency similar to that found in their infants. One of them died at age 33 years with a diagnosis of acquired immunodeficiency syndrome. In five of the children and in three of their mothers, there is evidence of a persistent Epstein-Barr virus (EBV) infection. We speculate that a perinatal or in utero transmission of EBV can induce an "infectious immunodeficiency." The clinical, histopathologic, and immunologic features resemble those described in adult homosexuals and drug addicts.

Two girls, one with progressive systemic sclerosis and a second with dermatomyositis, developed calcinosis in the skin of the prepatellar area. Calcinosis was accompanied by local inflammation and skin ulceration. Oral colchicine therapy in a dosage of 1 mg per day was followed within two months by significant regression of local inflammation and healing of the skin ulcers.