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11.
The pneumococcal pilus has been shown to be an important determinant of adhesion and virulence in mouse models of colonization, pneumonia, and bacteremia. A pilus is capable of inducing protective immunity, supporting its inclusion in next-generation pneumococcal protein vaccine formulations. Whether this vaccine target is common among pneumococci in sub-Saharan Africa is uncertain. To define the prevalence and genetic diversity of type I and II pili among invasive pneumococci in Malawi prior to the introduction of the 13-valent pneumococcal conjugate vaccine (PCV13) into routine childhood immunization, we examined 188 Streptococcus pneumoniae isolates collected between 2002 and 2008 (17% serotype 1). In this region of high disease burden, we found a low frequency of invasive piliated pneumococci (14%) and pilus gene sequence diversity similar to that seen previously in multiple global pneumococcal lineages. All common serotypes with pilus were covered by PCV13 and so we predict that pilus prevalence will be reduced in the Malawian pneumococcal population after PCV13 introduction.  相似文献   
12.
More than 10 years ago, the first pilot observational study of imatinib discontinuation was reported in chronic myeloid leukaemia (CML) patients in deep molecular response (DMR). Several studies have been published since then, in patients treated with frontline imatinib, or second-generation tyrosine kinase inhibitors (TKI) in first or second line but also on second attempt of TKI discontinuation. Our objective was to estimate, through meta-analyses of the literature data, the probability of molecular recurrence (MolRec) in the time periods of 0–6, 6–12, 12–18 and 18–24 months after a first and second TKI discontinuation and the probability of re-acquisition of DMR after MolRec. The Medline and Scopus databases were searched up to April 2019. The studies were selected by three independent reviewers. Random-effect meta-analyses were conducted using the MetaXL software. The probability of MolRec in the time periods 0–6, 6–12, 12–18 and 18–24 months after the first attempt was respectively 35%, 8%, 3% and 3%, whereas the probability of MolRec in the time periods 0-6, 6-12 and 12-18 after the second attempt was 48%, 27% and 12% respectively. Re-acquisition of a DMR was observed in 90% of patients. Most of the MolRec occur during the first six months in case of a first attempt, whereas the second MolRec occurs over a larger window of time.  相似文献   
13.
Archives of Women's Mental Health - Preliminary evidence suggests that mind-body interventions, including mindfulness-based interventions and yoga, may be effective in reducing mental health...  相似文献   
14.
Scavenger receptors on the cell surface of macrophages play an important role in host defence through their ability to bind microbial ligands and induce phagocytosis. Concurrently, signal transduction pathways are initiated that aid in defence mechanisms against the invading microbe. Here we report on the function of scavenger receptor Marco (Macrophage receptor with collagenous structure) during infection of zebrafish embryos with Mycobacterium marinum, a close relative of M. tuberculosis. Morpholino knockdown demonstrates that Marco is required for the rapid phagocytosis of M. marinum following intravenous infection. Furthermore, gene expression analysis shows that Marco controls the initial transient pro-inflammatory response to M. marinum and remains a determining factor for the immune response signature at later stages of infection. Increased bacterial burden following marco knockdown indicates that this scavenger receptor is important for control of M. marinum growth, likely due to delayed phagocytosis and reduced pro-inflammatory signalling observed under conditions of Marco deficiency.  相似文献   
15.
Objectives: The objective of the study was to determine whether parents who use a low-literacy, pictogram- and photograph-based written asthma action plan (WAAP) have a better understanding of child asthma management compared to parents using a standard plan. Methods: A randomized controlled study was carried out in 2 urban pediatric outpatient clinics. Inclusion criteria were English- and Spanish-speaking parents of 2- to 12-year-old asthmatic children. Parents were randomized to receive a low-literacy or standard asthma action plan (American Academy of Allergy, Asthma and Immunology) for a hypothetical patient on controller and rescue medications. A structured questionnaire was used to assess whether there was an error in knowledge of (1) medications to give everyday and when sick, (2) need for spacer use, and (3) appropriate emergency response to give albuterol and seek medical help. Multiple logistic regression analyses were performed, adjusting for parent age, health literacy (Newest Vital Sign); child asthma severity, medications; and site. Results: 217 parents were randomized (109 intervention and 108 control). Parents who received the low-literacy plan were (1) less likely to make an error in knowledge of medications to take everyday and when sick compared to parents who received the standard plan (63.0 vs. 77.3%, p = 0.03; adjusted odds ratio [AOR] = 0.5[95% confidence interval: 0.2–0.9]) and (2) less likely to make an error regarding spacer use (14.0 vs. 51.1%, p < 0.001; AOR = 0.1 [0.06–0.3]). No difference in error in appropriate emergency response was seen (43.1 vs. 48.1%, p = 0.5). Conclusions: Use of a low-literacy WAAP was associated with better parent understanding of asthma management. Further study is needed to assess whether the use of this action plan improves child asthma outcomes.  相似文献   
16.
The seed pods of Erythrina latissima yielded erysotrine, erysodine, syringaresinol, vanillic acid, a new erythrina alkaloid, (+)-10,11-dioxoerysotrine, which was lethal to brine shrimp and 2-(5'-hydroxy-3'-methoxy phenyl)-6-hydroxy-5-methoxybenzofuran, which showed strong antimicrobial activity against the yeast spores, Gram-positive and Gram-negative bacteria. The root bark gave four known pterocarpans which showed moderate to strong antifungal activity against the yeast spores and three known flavonoids showed antimicrobial activity against all test microorganisms.  相似文献   
17.
In a survey for primary paracoccidioidomycosis (PCM) infection (and not the clinical disease), two groups of blood donors were analyzed. One study group was drawn from donors living in a rural area where PCM is endemic, and the other group from urban residents of a large city, S?o Paulo. Anti-Paracoccidioides brasiliensis (Pb) specific antibodies (IgG) in sera were analyzed by ELISA, using crude Pb exoantigens (exoAg) and purified specific Pb 43 kDa glycoprotein (gp43). The results showed that 21% of 700 rural samples and 0.9% of 350 urban samples were positive for exoAg and gp43. To avoid cross-reactions, the sera were adsorbed first with Histoplasma capsulatum antigens and secondly with Leishmania amazonensis antigens. In the first adsorption with H. capsulatum, reactivity to gp43 fell to 12.8% in the rural group and to 0% in the urban group. In the succeeding adsorption with L. amazonensis, this reactivity fell to 12.3% in the rural group. There was a statistically greater proportion of persons with gp43-reactive antibodies in rural group than in the urban group, indicating that rural residents had frequently become exposed to Pb and contracted primary, subclinical PCM. The present report is the first epidemiological study using ELISA to detect antibodies against gp43 in blood donors.  相似文献   
18.
Urinary cadmium elimination and tissue distribution as well as that of zinc and copper were studied in groups of rats receiving 0 or 2.5 ppm Cd in water for 3, 6, or 12 months. By 3 months, cadmium ingestion induced only increases in urinary and kidney cadmium concentrations, after which urinary cadmium remained stable as a reflection of daily food intake. On the other hand, kidney cadmium accumulated reflecting total cadmium ingestion. In the livers and kidneys of animals observed during 3 and 6 months, cadmium accumulation was more marked in females, whether receiving cadmium or not. In other organs (liver, pancreas, ovary, testicle) cadmium concentrations were not higher in animals receiving cadmium. Kidney fixation of cadmium was associated with a slight decrease of hepatic copper after 3 months and a decrease in zinc as well after 12 months. These results attest that cadmium ingested at very low doses selectively accumulates in the kidney. They suggest either a mechanism unrelated to metallothionein synthesis or an early kidney induction.  相似文献   
19.
Attention has been drawn in recent years to the diagnostic interest offered by increases in serum gamma GT in the detection of liver metastases and various cancers in man. Although this analysis is not specific and presents a few false positive and negative results, it seems however profitable to include it either in detection or in supervision tests. Furthermore, in the rat and mouse, this enzyme practically absent from the adult liver, reappears during liver cancer Whatever the cause: this onco-foetal character may be useful to exploit in studies of experimental carcinogenesis, but does not seem to be a valid model for the increases observed in man.  相似文献   
20.
The tools currently used to evaluate the extent of paracoccidioidomycosis (PCM) may be of limited value in detecting subclinical lesions. The aim of this study was to verify the role of gallium-67 whole-body scan in evaluating the extent of disease of 65 patients with active PCM. The (67)Ga scan findings were compared with the results of clinical evaluation, chest radiography and/or high-resolution computed tomography (CT), abdominal ultrasound (US) or CT, laryngoscopy, CT or magnetic resonance imaging (MRI) of the head, and technetium-99m methylene diphosphonate bone scan, obtained before treatment. Clinically unsuspected lesions were detected by imaging procedures in 21 patients (32%), mainly in the lungs (n=11), adrenals (n=6), and superficial (n=3) and deep lymph nodes (n=14). (67)Ga scan detected 100% of the cases with subclinical involvement in the lungs. Scintigraphy was superior to chest radiography in demonstrating lung disease (94% vs 81%). The lymphatic lesions were demonstrated by (67)Ga scan in all the clinically suspected cases and in nearly all unsuspected cases, and also revealed more extensive involvement than was clinically suspected in many of them. There was good agreement between (67)Ga scan and the other imaging procedures for the initial detection of thoracic and abdominal lymph nodes and bone involvement. (67)Ga imaging detected most cases of laryngopharyngeal disease with active inflammatory lesions found at indirect laryngoscopy. On the other hand, (67)Ga scan failed to demonstrate most of the adrenal and CNS lesions detected by abdominal US/CT and head CT/MRI. In conclusion, (67)Ga imaging is a useful tool for evaluating the location and extent of suspected and unsuspected lesions in PCM. It could serve as a screening method before the use of other diagnostic procedures, particularly in the detection of lung, superficial and deep lymph node and bone involvement.  相似文献   
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