Nanoparticle-mediated Gene Silencing Confers Radioprotection to Salivary Glands In Vivo

Radiation treatment of head and neck cancers causes irreversible damage of the salivary glands (SG). Here, we introduce a preclinical mouse model for small-interfering RNA (siRNA)-based gene silencing to provide protection of SG from radiation-induced apoptosis. Novel, pH-responsive nanoparticles complexed with siRNAs were introduced into mouse submandibular glands (SMG) by retroductal injection to modulate gene expression in vivo. To validate this approach, we first targeted Nkcc1, an ion transporter that is essential for saliva secretion. Nkcc1 siRNA delivery resulted in efficient knockdown, as quantified at the mRNA and the protein levels, and the functional result of Nkcc1 knockdown phenocopied the severe decrease in saliva secretion, characteristic of the systemic Nkcc1 gene knockout. To establish a strategy to prevent apoptotic cell loss due to radiation damage, siRNAs targeting the proapoptotic Pkcδ gene were administered into SMG before ionizing radiation. Knockdown of Pkcδ not only reduced the number of apoptotic cells during the acute phase of radiation damage, but also markedly improved saliva secretion at 3 months in irradiated animals, indicating that this treatment confers protection from hyposalivation. These results demonstrate that nanoparticle delivery of siRNAs targeting a proapoptotic gene is a localized, nonviral, and effective means of conferring radioprotection to the SGs.     

Management and treatment of hepatitis C virus in patients with HIV and hepatitis C virus coinfection: A practical guide for health care professionals

Concomitant HIV and hepatitis C virus (HCV) is a common yet complex coinfection. The present document is a practical guide for treating HCV infection in people coinfected with HIV. Effective antiretroviral therapies have prolonged survival rates for HIV-infected people over the past decade, which have made latent complications of HCV major causes of morbidity and mortality in these patients. Advances in the treatment of HCV (eg, combined pegylated interferon and ribavirin) offer the possibility of eradicating HCV infection in coinfected persons. The treatment of HCV must be considered in all cases. Intensive management of the adverse effects of HCV treatment is one of the factors for the success of these therapies. HCV eradication is predicted to decrease the mortality associated with coinfection and reduce the toxicity of HIV treatment.     

Adolescent Substance Use Assessment in a Primary Care Setting

Health initiatives suggest that adolescent substance use assessment may be beneficial as part of primary care to screen for early problematic behaviors. To examine the accuracy of such reporting, we compared the anonymous and confidential self-reports of 180 adolescents in a primary care setting. Matching samples to control for demographic variables, we found that adolescents were more likely to report marijuana use and substance use behaviors, such as selling drugs, when reporting anonymously vs. reporting confidentially. These results challenge the accuracy of confidential self-reports within this setting, and suggest further research is needed.     

Risk of type 2 diabetes and cumulative excess weight exposure in the Framingham Offspring Study

AimMid-life obesity is associated with T2D risk. However, less is known about the cumulative effect of obesity during adulthood.MethodsFramingham Offspring Study participants who had an examination at 35 ± 2 years and were initially free of T2D were included in this study (N = 1026). A cumulative excess weight (CEW) score (year*kg/m²) was calculated until T2D diagnostic or the end of follow-up.ResultsEighty-four individuals (8.2%) developed T2D over 20 ± 6 years. Mean CEW scores were 118.0 ± 114.6 year*kg/m² in individuals who developed T2D and 30.2 ± 91.4 year*kg/m² in those who did not develop T2D (P < 0.01). T2D risk was doubled for each standard deviation increase in the CEW score (OR = 1.99 [1.64-2.40]; P < 0.001). However, CEW score was only significantly associated with T2D incidence for participants with a baseline BMI < 25 kg/m² (OR = 2.13 [1.36–3.36]; P < 0.001).ConclusionsAccumulating weight between the mid-thirties to the mid-fifties increases the risk of developing T2D. However, BMI in mid-thirties remains a stronger predictor of T2D risk.     

Characterization of patients with both alcoholic and nonalcoholic fatty liver disease in a large United States cohort

BACKGROUND Nonalcoholic fatty liver disease(NAFLD) is the hepatic manifestation of the metabolic syndrome(Met S) and is characterized by steatosis in the absence of significant alcohol consumption. However, Met S and significant alcohol intake coexist in certain individuals which may lead to the development of BAFLD.AIM To assess the clinical characteristics of patients with both alcoholic and NAFLD(BAFLD) in a large cohort in the United States.METHODS Adults from the National Health and Nutrition Examination Survey between2003-2014 were included. NAFLD was diagnosed based on elevated alanine aminotransferase(ALT) and being overweight or obese in the absence of other liver diseases. BAFLD patients met the criteria for NAFLD but also had either Met S or type 2 diabetes and consumed excessive amounts of alcohol. Univariable and multivariable analysis were performed to assess differences between NAFLD and BAFLD and to compare severity based on a validated fibrosis score(FIB4 index).RESULTS The prevalence of NAFLD was at 25.9%(95%CI; 25.1-26.8) and that of BAFLD was 0.84%(0.67, 1.02) which corresponds to an estimated 1.24 million Americans affected by BAFLD. Compared to NAFLD, patients with BAFLD were more likely to be male, smokers, have higher ALT, aspartate aminotransferase,triglycerides, and lower platelets; P 0.01 for all. More importantly, after adjusting for Met S components, BAFLD patients were significantly more likely to have advanced fibrosis [adjusted OR(95%CI) based on FIB4 index 2.67 was 3.2(1.4, 7.0), P = 0.004].CONCLUSION A significant percentage of the American general population is afflicted by BAFLD and these patients tend to have more advanced liver fibrosis.     

Clarification of the Innervation of the Bladder,External Urethral Sphincter and Clitoris: A Neuronal Tracing Study in Female Mongrel Hound Dogs

Many studies examining the innervation of genitourinary structures focus on either afferent or efferent inputs, or on only one structure of the system. We aimed to clarify innervation of the bladder, external urethral sphincter (EUS) and clitoris. Retrograde dyes were injected into each end organ in female dogs. Spinal cord, mid‐bladder, and spinal, caudal mesenteric, sympathetic trunk and pelvic plexus ganglia were examined for retrograde dye‐labeled neurons. Neurons retrogradely labeled from the bladder were found primarily in L7‐S2 spinal ganglia, spinal cord lateral zona intermedia at S1‐S3 levels, caudal mesenteric ganglia, T11‐L2 and L6‐S2 sympathetic trunk ganglia, and pelvic plexus ganglia. The mid‐bladder wall contained many intramural ganglia neurons labeled anterogradely from the pelvic nerve, and intramural ganglia retrogradely labeled from dye labeling sites surrounding ureteral orifices. Neurons retrogradely labeled from the clitoris were found only in L7 and S1 spinal ganglia, L7‐S3 spinal cord lateral zona intermedia, and S1 sympathetic trunk ganglia, and caudal mesenteric ganglia. Neurons retrogradely labeled from the EUS were found in primarily at S1 and S2 spinal ganglia, spinal cord lamina IX at S1‐S3, caudal mesenteric ganglia, and S1‐S2 sympathetic trunk ganglia. Thus, direct inputs from the spinal cord to each end organ were identified, as well as multisynaptic circuits involving several ganglia, including intramural ganglia in the bladder wall. Knowledge of this complex circuitry of afferent and efferent inputs to genitourinary structures is necessary to understand and treat genitourinary dysfunction. Anat Rec, 2018. © 2018 Wiley Periodicals, Inc.     

The response of NG2-expressing oligodendrocyte progenitors to demyelination in MOG-EAE and MS

Remyelination of primary demyelinated lesions is a common feature of experimental models of multiple sclerosis (MS) and is also suggested to be the normal response to demyelination during the early stages of MS itself. Many lines of evidence have shown that remyelination is preceded by the division of endogenous oligodendrocyte precursor cells (OPCs) in the lesion and its borders. It is suggested that this rapid response of OPCs to repopulate the lesion site and their subsequent differentiation into new oligodendrocytes is the key to the rapid remyelination. Antibodies to the NG2 chondroitin sulphate proteoglycan have proved exceedingly useful in following and quantitating the response of endogenous OPCs to demyelination. Here we review the literature on the response of NG2-expressing OPCs to demyelination and provide some new evidence on their response to the chronic inflammatory demyelinating environment seen in recombinant myelin oligodendrocyte glycoprotein (MOG) induced experimental allergic encephalomyelitis (EAE) in the DA rat. NG2-expressing OPCs responded to the inflammatory demyelination in this model by becoming reactive and increasing in number in a very focal manner. Evidence of NG2⁺OPCs in lesioned areas beginning to express the oligodendrocyte marker CNP was also seen. The response of OPCs appeared to occur following successive relapses but did not always lead to remyelination, with areas of chronic demyelination observed in the spinal cord. The presence of OPCs in the adult human CNS is clearly of vital importance for repair in multiple sclerosis (MS). As in rat tissue, the antibody labels an evenly distributed cell population present in both white and grey matter, distinct from HLA-DR⁺microglia. NG2⁺cells are sparsely distributed in the centre of chronic MS lesions. These cells apparently survive demyelination and exhibit a multi-processed or bipolar morphology in the very hypocellular environment of the lesion.     

Transient requirement of the PrrA-PrrB two-component system for early intracellular multiplication of Mycobacterium tuberculosis

Adaptive regulation of gene expression in response to environmental changes is a general property of bacterial pathogens. By screening an ordered transposon mutagenesis library of Mycobacterium tuberculosis, we have identified three mutants containing a transposon in the coding sequence or in the 5' regions of genes coding for two-component signal transduction systems (trcS, regX3, prrA). The intracellular multiplication capacity of the three mutants was investigated in mouse bone marrow-derived macrophages. Only the prrA mutant showed a defect in intracellular growth during the early phase of infection, and this defect was fully reverted when the mutant was complemented with prrA-prrB wild-type copies. The mutant phenotype was transient, as after 1 week this strain recovered full growth capacity to reach levels similar to that of the wild type at day 9. Moreover, a transient induction of prrA promoter activity was observed during the initial phase of macrophage infection, as shown by a prrA promoter-gfp fusion in M. bovis BCG infecting the mouse macrophages. The concordant transience of the prrA mutant phenotype and prrA promoter activity indicates that the PrrA-PrrB two-component system is involved in the environmental adaptation of M. tuberculosis, specifically in an early phase of the intracellular growth, and that, similar to other facultative intracellular parasites, M. tuberculosis can use genes temporarily required at different stages in the course of macrophage infection.