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41.

Background

Mycobacteria, such as M. leprae and M. tuberculosis infect billions of humans. However, because of appropriate immune responses and antibiotic therapy, overt mycobacterial diseases occur far less frequently. M. avium subspecies paratuberculosis (MAP) causes Johne''s disease in ruminants, an affliction evocative of inflammatory bowel disease (IBD). Several agents used to treat IBD (5-ASA, methotrexate, azathioprine and its metabolite 6-MP) have recently been shown to be antiMAP antibiotics. We herein evaluate the prevalence of MAP DNA in healthy individuals and compare them with IBD patients on antiMAP antibiotics.

Methods

We studied 100 healthy individuals (90 blood donors) and 246 patients with IBD. IS900 MAP DNA was identified using a nested primer PCR in the buffy coat of blood. Positive signal was confirmed as MAP by DNA sequence analysis. PCR positive results frequencies were compared according to medications used. Significance was accepted at p<0.05.

Results

47% (47/100) healthy controls and 16% (40/246) IBD patients were IS900 positive (p<0.0001). MAP DNA was identified in 17% of 143 patients receiving mesalamine and 6% of 16 receiving sulfasalazine. None of the IBD patients receiving methotrexate (n = 9), 6-MP (n = 3), ciprofloxacin (n = 5) or Tacrolimus® (n = 3) had MAP DNA detectable in their blood.

Discussion

We found a disquietingly large percentage of healthy individuals have MAP DNA in their blood, the significance of which remains to be determined. Counter-intuitively, the incidence of MAP DNA was significantly lower in patients with IBD. Agents with the most potent in vitro antiMAP activity were associated with clearance of blood MAP DNA. We posit that the use antiMAP antibiotics was responsible for the decreased prevalence of MAP DNA in patients with IBD.  相似文献   
42.
Human phospholipid scramblase 1 (SCR) consists of a large cytoplasmic domain and a small presumed transmembrane domain near the C-terminal end of the protein. Previous studies with the SCRΔ mutant lacking the C-terminal portion (last 28 aa) revealed the importance of this C-terminal moiety for protein function and calcium-binding affinity. The present contribution is intended to elucidate the effect of the transmembrane domain suppression on SCRΔ binding to model membranes (lipid monolayers and bilayers) and on SCRΔ reconstitution in proteoliposomes. In all cases the protein cytoplasmic domain showed a great affinity for lipid membranes, and behaved in most aspects as an intrinsic membrane protein. Assays have been performed in the presence of phosphatidylserine, presumably important for the SCR cytoplasmic domain to be electrostatically anchored to the plasma membrane inner surface. The fusion protein maltose binding protein-SCR has also been studied as an intermediate case of a molecule that can insert into the bilayer hydrophobic core, yet it is stable in detergent-free buffers. Although the intracellular location of SCR has been the object of debate, the present data support the view of SCR as an integral membrane protein, in which not only the transmembrane domain but also the cytoplasmic moiety play a role in membrane docking of the protein.  相似文献   
43.
Pectin Lyase Activity in a Penicillium italicum Strain   总被引:2,自引:0,他引:2       下载免费PDF全文
An extracellular pectin lyase (PNL) [poly-(methoxygalacturonide)lyase; EC 4.2.2.10] produced by Penicillium italicum CECT 2294 grown on a surface bran (natural medium) or in a submerged (synthetic medium) culture was investigated. Both culture filtrates showed macerating activity at low pH on cucumber, potato, and orange tissues. The physicochemical properties of the enzyme obtained from both culture methods were identical, as well as its catalytic properties, which were assayed by different methods. The molecular mass of the PNL obtained by gel filtration chromatography was 22 kDa; the isoelectric point was 8.6, as determined by chromatofocusing; and the enzyme was able to catalyze the eliminative cleavage of pectins with low (37%) and high (from 54 to 82%) degrees of esterification. The PNL produced in liquid medium showed a Km for pectin (degree of esterification, 70%) of 3.2 mg/ml, and the optimum pH was 6.0 to 7.0. This enzyme was stable at 50°C and at pH 8.0. The ability of this PNL to macerate plant tissues in acidic environmental conditions, its stability at low pH and temperatures up to 50°C (thus preventing mesophilic microbial growth), and the absence of pectinesterase make this preparation useful for the food industry.  相似文献   
44.
TrwB is an integral membrane protein encoded by the conjugative plasmid R388. TrwB binds ATP and is essential for R388-directed bacterial conjugation. The protein consists of a cytosolic domain, which contains an ATP-binding site, and a transmembrane domain. The complete protein has been purified in the presence of detergents, and in addition, the cytosolic domain has also been isolated in the form of a soluble truncated protein, TrwBDeltaN70. The availability of intact and truncated forms of the protein provides a convenient system to study the role of the transmembrane domain in the stability of TrwB. Protein denaturation was achieved by heat, in the presence of guanidinium HCl, or under low salt conditions. In all three cases TrwB was significantly more stable than TrwBDeltaN70 with other conditions being the same. IR spectroscopy of the native and truncated forms revealed significant differences between them. In addition, it was found that TrwBDeltaN70 was stabilized in dispersions of non-ionic detergent, suggesting the presence of hydrophobic patches on the surface of the truncated protein. IR spectroscopy also confirmed the conformational stability provided by the detergent. These results suggest that in integral membrane proteins consisting of a transmembrane and a cytosolic domain, the transmembrane portion may have a role beyond the mere anchoring of the protein to the cell membrane. In addition, this study indicates that the truncated soluble parts of two-domain membrane proteins may not reflect the physiological conformation of their native counterparts.  相似文献   
45.
The objective of this study was to determine the effect of a sustained propylene glycol administration to recipients of frozen/thawed in vivo derived bovine embryos. Heifers were treated with oral propylene glycol for the last 20 days before embryo transfer (n = 142), and untreated as controls (n = 133). Progesterone, insulin, insulin-like growth factor-I, glucose, urea and triglyceride were analysed in blood on Day 0 and Day 7 of the estrous cycle corresponding to embryo transfer. The heifers were selected as recipients when showing progesterone levels <2.0 ng/ml (Day 0) and >2.5 ng/ml (Day 7), according to corpus luteum quality on Day 7 by technicians unaware of animals treated. Within treated animals, significantly more recipients were selected, and increased progesterone, corpus luteum quality, pregnancy and calving rates were recorded. Day 7 progesterone concentrations were higher in heifers treated and transferred. Propylene glycol increased insulin and insulin-like-growth factor-I, but glucose, urea and triglyceride did not vary. Furthermore, insulin-like-growth factor-I, glucose and triglyceride increased at estrous time, but urea decreased and insulin remained unaltered. Together with the sustained gain in pregnancy rates throughout the experiment (2 years), other evidences suggested that the observed effects did not rely on nutritional deficiency. Thus, propylene glycol improved pregnancy rates after embryo-transfer, and progesterone, insulin and insulin-like-growth factor-I are probably involved in this effect.  相似文献   
46.
Geoffrey M. Reed  Jared W. Keeley  Tahilia J. Rebello  Michael B. First  Oye Gureje  José Luis Ayuso‐Mateos  Shigenobu Kanba  Brigitte Khoury  Cary S. Kogan  Valery N. Krasnov  Mario Maj  Jair de Jesus Mari  Pratap Sharan  Dan J. Stein  Min Zhao  Tsuyoshi Akiyama  Howard F. Andrews  Elson Asevedo  Majda Cheour  Tecelli Domínguez‐Martínez  Joseph El‐Khoury  Andrea Fiorillo  Jean Grenier  Nitin Gupta  Lola Kola  Maya Kulygina  Itziar Leal‐Leturia  Mario Luciano  Bulumko Lusu  J. Nicolás I. Martínez‐López  Chihiro Matsumoto  Mayokun Odunleye  Lucky Umukoro Onofa  Sabrina Paterniti  Shivani Purnima  Rebeca Robles  Manoj K. Sahu  Goodman Sibeko  Na Zhong  Wolfgang Gaebel  Anne M. Lovell  Toshimasa Maruta  Kathleen M. Pike  Michael C. Roberts  María Elena Medina‐Mora 《World psychiatry》2018,17(3):306-315
In this paper we report the clinical utility of the diagnostic guidelines for ICD‐11 mental, behavioural and neurodevelopmental disorders as assessed by 339 clinicians in 1,806 patients in 28 mental health settings in 13 countries. Clinician raters applied the guidelines for schizophrenia and other primary psychotic disorders, mood disorders (depressive and bipolar disorders), anxiety and fear‐related disorders, and disorders specifically associated with stress. Clinician ratings of the clinical utility of the proposed ICD‐11 diagnostic guidelines were very positive overall. The guidelines were perceived as easy to use, corresponding accurately to patients’ presentations (i.e., goodness of fit), clear and understandable, providing an appropriate level of detail, taking about the same or less time than clinicians’ usual practice, and providing useful guidance about distinguishing disorder from normality and from other disorders. Clinicians evaluated the guidelines as less useful for treatment selection and assessing prognosis than for communicating with other health professionals, though the former ratings were still positive overall. Field studies that assess perceived clinical utility of the proposed ICD‐11 diagnostic guidelines among their intended users have very important implications. Classification is the interface between health encounters and health information; if clinicians do not find that a new diagnostic system provides clinically useful information, they are unlikely to apply it consistently and faithfully. This would have a major impact on the validity of aggregated health encounter data used for health policy and decision making. Overall, the results of this study provide considerable reason to be optimistic about the perceived clinical utility of the ICD‐11 among global clinicians.  相似文献   
47.
Tahilia J. Rebello  Jared W. Keeley  María Elena Medina‐Mora  Oye Gureje  José Luis Ayuso‐Mateos  Shigenobu Kanba  Brigitte Khoury  Cary S. Kogan  Valery N. Krasnov  Mario Maj  Jair de Jesus Mari  Dan J. Stein  Min Zhao  Tsuyoshi Akiyama  Howard F. Andrews  Elson Asevedo  Majda Cheour  Tecelli Domínguez‐Martínez  Joseph El‐Khoury  Andrea Fiorillo  Jean Grenier  Nitin Gupta  Lola Kola  Maya Kulygina  Itziar Leal‐Leturia  Mario Luciano  Bulumko Lusu  J. Nicolas  I. Martínez‐López  Chihiro Matsumoto  Lucky Umukoro Onofa  Sabrina Paterniti  Shivani Purnima  Rebeca Robles  Manoj K. Sahu  Goodman Sibeko  Na Zhong  Michael B. First  Wolfgang Gaebel  Anne M. Lovell  Toshimasa Maruta  Michael C. Roberts  Kathleen M. Pike 《World psychiatry》2018,17(2):174-186
Reliable, clinically useful, and globally applicable diagnostic classification of mental disorders is an essential foundation for global mental health. The World Health Organization (WHO) is nearing completion of the 11th revision of the International Classification of Diseases and Related Health Problems (ICD‐11). The present study assessed inter‐diagnostician reliability of mental disorders accounting for the greatest proportion of global disease burden and the highest levels of service utilization – schizophrenia and other primary psychotic disorders, mood disorders, anxiety and fear‐related disorders, and disorders specifically associated with stress – among adult patients presenting for treatment at 28 participating centers in 13 countries. A concurrent joint‐rater design was used, focusing specifically on whether two clinicians, relying on the same clinical information, agreed on the diagnosis when separately applying the ICD‐11 diagnostic guidelines. A total of 1,806 patients were assessed by 339 clinicians in the local language. Intraclass kappa coefficients for diagnoses weighted by site and study prevalence ranged from 0.45 (dysthymic disorder) to 0.88 (social anxiety disorder) and would be considered moderate to almost perfect for all diagnoses. Overall, the reliability of the ICD‐11 diagnostic guidelines was superior to that previously reported for equivalent ICD‐10 guidelines. These data provide support for the suitability of the ICD‐11 diagnostic guidelines for implementation at a global level. The findings will inform further revision of the ICD‐11 diagnostic guidelines prior to their publication and the development of programs to support professional training and implementation of the ICD‐11 by WHO member states.  相似文献   
48.
Heathland vegetation of northern Spain, included in theCalluno-Ulicetea, was studied using a set of 802 phytosociological relevés. The existing syntaxonomy has been tested and most of the types (associations and subassociations) fit satisfactorily with the observed groupings. Two main problems were encountered within theUlex dominated communities of the Cantabrian fringe and the Castilian-Cantabrian heathland communities. Both groups of communities were subject to ordination in order to clarify relationships between them. For the former group, ordination suggests that three associations can be distinguished: theUlici-Ericetum vagantis (lowlands up to the submontane belt), theVaccinio-Ulicetum gallii for the communities of higher altitudes (montane belt) and theUlici-Ericetum ciliaris (hygrophilous heathlands). The Castilian-Cantabrian heathlands show a variable Mediterranean influence and have a dispersed distribution due to lithological conditions. This results in the distinction of two new associations, viz. theArctostaphylo crassifoliae-Daboecietum cantabricae (marly, water-retaining soils) and theEricetum scopario-vagantis (sandy soils). A complete classification of theCalluno-Ulicetea in the studied area and short ecological and biogeographical diagnoses are given.  相似文献   
49.
BACKGROUND:Although annual influenza vaccination is recommended for persons with asthma, its effectiveness in this patient population is not well described. We evaluated the effect of influenza vaccination in the current and previous seasons in preventing influenza among people with asthma.METHODS:Using population health data from the Navarre region of Spain for the 2015/16 to 2019/20 influenza seasons, we conducted a test-negative case–control study to assess the effect of influenza vaccination in the current and 5 previous seasons. From patients presenting to hospitals and primary health care centres with influenza-like illness who underwent testing for influenza, we estimated the effects of influenza vaccination among patients with asthma overall and between those presenting as inpatients or outpatients, as well as between patients with and without asthma.RESULTS:Of 1032 patients who had asthma and were tested, we confirmed that 421 had influenza and the remaining 611 were test-negative controls. We found that the average effect of influenza vaccination was 43% (adjusted odds ratio [OR] 0.57, 95% confidence interval [CI] 0.40 to 0.80) for current-season vaccination regardless of previous doses, and 38% (adjusted OR 0.62, 95% CI 0.39 to 0.96) for vaccination in previous seasons only. Effects were similar for outpatients and inpatients. Among patients with asthma and confirmed influenza, current-season vaccination did not reduce the odds of hospital admission (adjusted OR 1.05, 95% CI 0.51 to 2.18). Influenza vaccination effects were similar for patients with and without asthma.INTERPRETATION:We estimated that, on average, current or previous influenza vaccination of people with asthma prevented almost half of influenza cases. These results support recommendations that people with asthma receive influenza vaccination.

Influenza can lead to serious complications in people with risk factors, and the main preventive measure is vaccination. 1 Influenza infection can exacerbate symptoms of asthma. Because people with asthma have an increased risk of severe complications and hospital admission when infected with influenza virus,25 annual influenza vaccination is recommended worldwide for people with asthma.1,58People who are targeted for influenza vaccination frequently accumulate several doses over successive years,9 and adherence to influenza vaccination has been found to be higher in those with asthma.10 Patients with asthma frequently receive long-term corticosteroid treatment (inhaled or oral), therefore, their systemic immunity may have a reduced response to vaccines.5,11,12Effectiveness of influenza vaccines in preventing primary health care consultations or hospital admissions in people with asthma has been evaluated in observational studies,1315 but we are unaware of any studies that compared the effect in preventing outpatient and inpatient cases or assessed the effect of vaccination in previous seasons.13,16 The test-negative design is the suggested method to evaluate effectiveness of influenza vaccines in preventing laboratory-confirmed influenza, because it achieves good comparability and control of bias.1719 Only 1 study used this method for people with asthma over several seasons.13 The pooled analysis of several seasons, the inclusion of inpatients and outpatients, and consideration of vaccination history would provide a complete view of the effect of influenza vaccination in people with asthma.Our objective was to assess the average effect of influenza vaccination status in the current and previous seasons on preventing laboratory-confirmed influenza among people with asthma. We also aimed to compare these estimates with those of the target population for influenza vaccination.  相似文献   
50.
Chronic hepatitis B is a major cause of liver-related death worldwide. Interleukin-12 (IL-12) induction accompanies viral clearance in chronic hepatitis B virus infection. Here, we tested the therapeutic potential of IL-12 gene therapy in woodchucks chronically infected with woodchuck hepatitis virus (WHV), an infection that closely resembles chronic hepatitis B. The woodchucks were treated by intrahepatic injection of a helper-dependent adenoviral vector encoding IL-12 under the control of a liver-specific RU486-responsive promoter. All woodchucks with viral loads below 1010 viral genomes (vg)/ml showed a marked and sustained reduction of viremia that was accompanied by a reduction in hepatic WHV DNA, a loss of e antigen and surface antigen, and improved liver histology. In contrast, none of the woodchucks with higher viremia levels responded to therapy. The antiviral effect was associated with the induction of T-cell immunity against viral antigens and a reduction of hepatic expression of Foxp3 in the responsive animals. Studies were performed in vitro to elucidate the resistance to therapy in highly viremic woodchucks. These studies showed that lymphocytes from healthy woodchucks or from animals with low viremia levels produced gamma interferon (IFN-γ) upon IL-12 stimulation, while lymphocytes from woodchucks with high viremia failed to upregulate IFN-γ in response to IL-12. In conclusion, IL-12-based gene therapy is an efficient approach to treat chronic hepadnavirus infection in woodchucks with viral loads below 1010 vg/ml. Interestingly, this therapy is able to break immunological tolerance to viral antigens in chronic WHV carriers.Hepatitis B virus (HBV) infection is estimated to cause approximately 1 million deaths per year (http://www.who.int/emc). Current therapies against chronic HBV include pegylated alpha interferon (IFN-α) and nucleoside/nucleotide analogs, such as lamivudine, entecavir, adefovir, and tenofovir (16). Sustained antiviral responses are achieved in only one-third of the patients treated with pegylated IFN-α (16, 32). Nucleoside/nucleotide analogs are effective, but treatment must be continued for many years, resulting in high costs, the emergence of drug-resistant variants, and frequent relapses after the discontinuation of therapy (32).Chronic HBV infection is associated with defects in antiviral immunity (3). Patients with an acute self-limiting HBV infection develop neutralizing anti-HBs antibodies and multispecific CD4+ and CD8+ T-cell responses with a type 1 cytokine profile (3). In contrast, patients with chronic HBV infection show no protective humoral immunity and a weak or undetectable virus-specific T-cell response (5). The precise mechanism responsible for this immunotolerance is still unknown. Recently, several studies have indicated that regulatory T cells (Tregs), immunosuppressive cytokines, and inhibitory receptor-ligand interactions, such as PD1-PDL1, contribute to the impairment of virus-specific T-cell responses in chronic HBV infection (1, 17, 23, 26, 28).Interleukin-12 (IL-12) is a cytokine produced by antigen-presenting cells that is essential for the induction of effective cell-mediated immunity against viruses and other pathogens (30). IL-12 promotes Th1-type responses, enhances cytotoxic-T-cell activity, and stimulates T lymphocytes and NK cells to produce IFN-γ (30). The administration of recombinant IL-12 (rIL-12) to HBV-transgenic mice resulted in the inhibition of HBV replication in the liver (8). In vitro studies demonstrated that IL-12 was able to enhance HBV-specific T-cell responses in chronic HBV carriers (15, 22, 31). Moreover, the upregulation of IL-12 production has been shown to be associated with HBe seroconversion, indicating an important role for this cytokine in the control of HBV infection (22). In two studies, rIL-12 administered to patients with chronic HBV infection once per week as monotherapy (7) or twice weekly in combination with lamivudine (21) increased virus-specific T-cell reactivity and exerted significant antiviral activity. However, in both studies, a rebound of viremia occurred following drug withdrawal. The antiviral effects of rIL-12 were dose dependent, but the therapy was limited by severe toxicity when high doses of the cytokine were used (7, 21).Gene therapy can significantly increase cytokine expression in the target organ without excessively elevating systemic cytokine levels, which leads to an increased efficacy/toxicity ratio. In the present study, we tested the antiviral potential of IL-12-mediated gene therapy using a high-capacity adenovirus (HC-Ad) encoding murine IL-12 (mIL-12) under the control of a liver-specific inducible promoter that is responsive to the progesterone antagonist RU486 (30). HC-Ad is a nonintegrating vector characterized by strong hepatotropism, low toxicity, long-term transgene expression, and high cloning capacity (13). All these properties make HC-Ad a useful tool for therapeutic applications in human liver diseases.As an animal model of chronic HBV infection, we used woodchucks that were chronically infected with woodchuck hepatitis virus (WHV). WHV is a hepadnavirus with a genomic organization, biological properties, and a replicative strategy that are essentially identical to those of HBV. When WHV infects woodchucks in the perinatal period of life, the infection causes chronic hepatitis in most animals. This condition resembles the pathological features and natural history of chronic hepatitis B (18). Here, we demonstrate that prolonged intrahepatic expression of IL-12 overcomes immunological tolerance for WHV antigens and induces sustained antiviral effects in woodchucks with chronic WHV infection and viral loads below 1010 viral genomes (vg)/ml. These observations indicate that IL-12 gene therapy is an alternative approach for the treatment of chronic HBV infection.  相似文献   
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