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ABSTRACT

A monocausal bacteriological understanding of infectious disease orients tuberculosis control efforts towards antimicrobial interventions. A bias towards technological solutions can leave multistranded public health and social interventions largely neglected. In the context of globalising biomedical approaches to infectious disease control, this ethnography-inspired review article reflects upon the implementation of rapid diagnostic technology in low- and middle-income countries. Fieldwork observations in Vietnam provided a stimulus for a critical review of the global rollout of tuberculosis diagnostic technology. To address local needs in tuberculosis control, health managers in resource-poor settings are readily cooperating with international donors to deploy novel diagnostic technologies throughout national tuberculosis programme facilities. Increasing investment in new diagnostic technologies is predicated on the supposition that these interventions will ameliorate disease outcomes. However, suboptimal treatment control persists even when accurate diagnostic technologies are available, suggesting that promotion of singular technological solutions can distract from addressing systemic change, without which disease susceptibility, propagation of infection, detection gaps, diagnostic delays, and treatment shortfalls persist.  相似文献   
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Transplant ureteric stent insertion reduces the incidence of MUCs, but it is not known whether routine PSRGU is needed to detect unmasked MUCs. This study evaluated whether routine PSRGU in the pRTR is a useful tool to identify MUCs before they become clinically apparent. A retrospective analysis was undertaken of the clinical outcomes following elective stent removal from pediatric kidney‐only transplant recipients at two London centers between 2012 and 2016. Our policy was to perform PSRGU either routinely or urgently if there were concerning symptoms or biochemical evidence of renal allograft dysfunction. Elective stent removal was performed in 86% (97 of 113 pRTR), and 75 (77%) of whom had routine PSRGU at a median (IQR) of 6 (2‐8) days after stent removal. There were changes to management in 3 (4%) of pRTR with PSRGU identifying no MUC. Nineteen patients (25%) had urgent PSRGU, most commonly due to renal allograft dysfunction, at a median (IQR) of 5.5 (2.7‐12.3) days after stent removal. Of these, two pRTR required ureteric intervention. For our current practice of removing transplant stents at 4‐6 weeks post‐transplantation, our study has found no evidence to support routine PSRGU after elective stent removal.  相似文献   
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Langerhans cell histocytosis (LCH) and Erdheim‐Chester disease are two rare histiocytic disorders. Their occurrence in the same patient is more infrequent, but has been described. We report a case of a 38‐year‐old woman who presented with a diagnosis of single system cutaneous LCH. Subsequently, she developed multiple papules on her extremities consistent with a non‐LCH xanthogranuloma type lesion. BRAFV600E mutation immunostain, VE1 was positive in the skin lesion, which was confirmed by molecular polymerase chain reaction (PCR) studies, initiating a complete systemic workup for Erdheim‐Chester disease. Systemic involvement was confirmed with bilateral sclerotic bone lesions and retroperitoneal and pelvic fibrosing disease. She was also found to have a BRAFV600E mutation positive papillary thyroid carcinoma. New suspicious cutaneous lesions presenting in patients with a history of LCH need to be biopsied. A BRAFV600E mutation in a non‐LCH histiocytic lesion with a xanthogranuloma phenotype (CD163/CD68/CD14/fascin/Factor 13a) should prompt an Erdheim‐Chester disease workup. This is a unique case of a woman with BRAFV600E mutation positive Erdheim‐Chester disease and cutaneous LCH, while also being, to our knowledge, the first reported case in the English literature of it occurring in a patient with a BRAFV600E mutation positive papillary thyroid carcinoma.  相似文献   
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Objective  Practical treatment of halitosis requires tongue cleaning since volatile sulphur compounds (VSC) seems mainly to be from the tongue coating. From this point of view, mechanical tools such as tongue brushes or scrapers have been developed. However, approaches by chemical tongue cleaning have not been reported. Thus we developed tablets containing protease from kiwifruits, which could resolve tongue coating, and assessed the effects of the protease tablet to control tongue coating.
Methods  Crossover studies and double blind experiments were designed using volunteers with informed consent. The trial was done twice per volunteer, that is, they had a tablet with or without the addition of protease from kiwifruits (test and placebo) with intervening washout periods of at least 2 weeks. The degree of change in tongue coating was evaluated visually using a tongue coating score which consisted of an area component (0–3) and a thickness component (0–3). An image analyzer was also used to measure the changing in actual area of coating.
Results  The average value of the tongue coating scores after taking a test tablet (11.4 ± 5.2) was significantly smaller ( P  < 0.01) than before taking the tablet (18.8 ± 7.0). Image analyzer measurements also showed significant reduction ( P  < 0.01) of tongue coating by taking test tablet. On the other hand, a placebo tablet showed no significant effects in both analyses.
Conclusions  This study indicated that taking protease tablets could reduce tongue coating. We are planning further clinical trials that can show reduced VSC concentrations in mouth air with decreasing tongue coating.  相似文献   
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OBJECTS: This report describes one of the first prospective studies delineating the relationship between infection, host antibody responses and disease exacerbations and remissions in a distinct subset of periodontitis patients infected with A. actinomycetemcomitans. DESIGN: The design of this longitudinal study included visits for each patient approximately every 2 months for up to 3 years. SUBJECTS AND METHODS: Subjects (n = 51) included 16 adult periodontitis (AP) and 11 early-onset periodontitis (EOP) patients with elevated serum IgG antibody to A. actinomycetemcomitans and infection with this microorganism, 12 AP patients with normal levels of anti-Aa antibody, and 12 normal subjects. MEASUREMENT OUTCOMES: Clinical parameters included a gingival index, plaque index, bleeding on probing, pocket depth, and attachment level. Disease activity was defined as loss of attachment during the monitoring intervals. Serum IgG, IgM and IgA antibody to A. actinomycetemcomitans Y4 (serotype b) was quantit-ated using an ELISA. Subgingival plaque samples were examined for A. actinomycetemcomitans using colony immunobiotting. Human serum IgG antibody specificities to outer membrane antigens (OMA) of A. actinomycetemcomitans Y4 were determined using Western immunoblotting. RESULTS: A. actinomycetemcomitans-infected AP patients had a higher frequency of teeth infected when compared to the EOP patients. However, the EOP patients exhibited a trend for higher levels of A. actinomycetemcomitans in those teeth that were infected. Active disease patients demonstrated a significantly greater frequency of infected sites, as well as significant elevations in the proportions of A. octinomycetemcomitans. Both EOP and AP groups showed significantly elevated IgG, IgM and IgA antibody to A. actinomycetemcornitans when compared to a periodontally normal group. The level of IgG antibody was significantly elevated in A. actinomycetemcomitans-positive patients with active disease, while IgA antibody was decreased in a number of the active group patients. Plaque samples derived from active sites showed a clear and significant increase in A. actinomycetemcomitans that occurred from 2–6 months prior to the identification of disease activity. Approximately 70% of the active disease patients showed an increase in IgG antibody level by 2–4 months prior to disease activity. Studies of the antigen reactivity patterns of serum IgG indicated that antibody to antigens of 65, 58, 48, 29 and 24 kDa were more frequent in patients who showed active disease, while those patients with the greatest frequency of active disease appeared to show a general decrease in the recognition of the A. actinomycetemcomitans OMA. CONCLUSIONS: It appears that A. actinomycetemcomitans infection relates to a particular type of disease with accompanying antibody responses that reflect periods of active disease. The dynamics of A. actinomycetemcomitans infection and the level and specificity of systemic antibody responses to this pathogen support an important contribution of the immune response to managing this infection.  相似文献   
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In this study two different opaque porcelain-metal combinations were evaluated for planar shear bond strength. Samples were tested after one, three, five, seven, and nine different firing cycles to evaluate the effect of repeated firing on shear bond strength. For the combination of Will Ceram/W1 and Vita/Olympia materials, no statistical difference was observed either between materials or after repeated firing. For apparently well-matched porcelain-metal combinations, no significant reduction in bond strength occurs during normal firing of the opaque porcelain to the metal.  相似文献   
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