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Little information is available on the effect of miswak use on gingival microbiota. We assessed levels of 28 oral bacteria in subgingival plaque of adult Sudanese miswak (n = 38) and toothbrush users (n = 36) age range 20-53 years (mean 34.6 years) to study associations between these bacteria, oral hygiene method, and periodontal status at the sampled sites. A pooled subgingival plaque sample from 6 probing sites of 1 selected tooth in each jaw was obtained from each subject. Whole genomic DNA probes and the checkerboard DNA-DNA hybridization were used in assessing 74 pooled samples. Using 10(5) bacterial cells threshold, between 2.6% and 47.4% of miswak users and between 2.8% and 36.1% of toothbrush users harbored the investigated species. The percentages of subjects with the investigated species at 10(6) bacterial cells varied between 2.6% and 39.5% in miswak and between 2.8% and 36.1% in toothbrush users. Miswak users harbored significantly higher Streptococcus intermedius, Actinobacillus actinomycetemcomitans, Veillonella parvula, Actinomyces israelii, and Capnocytophaga gingivalis, and significantly lower Selenomonas sputigena, Streptococcus salivarius, Actinomyces naeslundii, and Streptococcus oralis than did toothbrush users. Probing pocket depth > or = 6 mm showed significantly (P < 0.05) higher levels of Porphyromonas gingivalis, Treponema denticola, Bacteroides forsythus, Fusobacterium nucleatum, and V. parvula than those 4-5 mm. Our results indicate that the type of oral hygiene had a significant effect on levels of 11 out of 28 bacterial species, and that the type of effect was also dependent on type of bacteria and probing pocket depth.  相似文献   
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Models such as the Biotic Ligand Model (BLM) predict how natural organic matter (NOM) and competing ions (e.g., Ca(2+), H(+) and Na(+)) affect metal bioavailability and toxicity in aquatic organisms. However, such models focus upon individual metals, not metal mixtures. This study determined whether Pb and Cd interact at the gill of rainbow trout (Oncorhynchus mykiss) when trout were exposed to environmentally relevant concentrations of these metals (Cd<100nmolL(-1); Pb<500nmolL(-1)) in soft (<100mumolCa(2+)L(-1)), moderately acidic (pH 6.0) water. The 96-h LC50 for Pb was 482nmolL(-1), indicating that Pb was one-order of magnitude more toxic in soft, acidic water than in harder, circumneutral pH waters. The LC50 for Cd alone was also low, 6.7nmolL(-1). Surprisingly, fish acclimated to soft water had multiple populations of Pb-gill and Cd-gill binding sites. A low capacity, high affinity population of Pb-gill binding sites had a B(max) of 18.2nmolg(-1) wet weight (ww) and apparent logK(Pb-gill)=7.05, but a second low affinity population could not be saturated up to free Pb concentrations approaching 4000nmolL(-1). Two populations of Cd-gill binding sites were characterized: a high affinity, low capacity population with an apparent logK(Cd-gill)=7.33 and B(max)=1.73nmolg(-1) ww, and a low affinity, high capacity population with an apparent logK(Cd-gill)=5.86, and B(max)=13.7nmolg(-1) ww. At low concentrations, Cd plus Pb accumulation was less than additive because Cd out-competed Pb for gill binding sites, which were likely apical Ca(2+)-channels. While disturbances to Ca(2+) influx were caused by Cd alone, Pb alone had no effect. However, Pb exacerbated Cd-induced disturbances to Ca(2+) influx demonstrating that, although Pb- plus Cd-gill binding was less than additive due to competition, the effects (ionic disturbances) were more than additive (synergistic). Pb was also likely binding to intracellular targets, such as branchial carbonic anhydrase, which led to inhibited Na(+) influx. This ionic disturbance was exacerbated by Cd. We conclude that exposure to environmentally relevant concentrations of Pb plus Cd results in less than additive metal-gill binding in soft, moderately acidic waters. However, ionic disturbances caused by Cd plus Pb are greater than additive, and this may ultimately increase the toxicity of Cd-Pb mixtures to fishes. Our findings suggest that it may be necessary to re-evaluate water quality criteria and assumptions of the BLM for fish exposed to mixtures of Pb and Cd in the acidic, soft waters found in the Canadian Shield, Scandinavia and other sensitive regions.  相似文献   
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Inflammation - Hidradenitis suppurativa (HS) is a complex and debilitating&nbsp;inflammatory skin disease for which no effective treatment is available currently. This is partly because of the...  相似文献   
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The 2-morpholino-substituted-benzoxazines 7a and 7b were used in the synthesis of 2-morpholino-di-O-benzyl, O-pyridin-2yl, 3-yl and 4yl-methoxy)-1,3-benzoxazines 8a–8d, and N-(2-morpholino-4-oxo-4H-benz[e][1,3]oxazin-7-yl)-N-(pyridin-2-and-3-ylmethyl)acetamides 8e and 8f. The DNA-dependent protein kinase (DNA-PK) and phosphatidylinositol 3-kinase (PI3K) α, β, γ, and δ isoforms were studied for the new compounds 8a8f and PI3K for the 18 previously synthesized compounds 926. The most active DNA-PK inhibitors were the 2-morpholino-O-substituted linear or angular naphthoxazine compounds 1820 and 2122 which showed potent and selective DNA-PK activity (IC50 from 0.01 to 2.43 µM) over PI3K. 8-(2-(4-Methylpiperazin-1-yl)ethoxy)-2-morpholino compound 13, and 8-methyl-2-(pyridin-3-yl(pyridin-3-ylmethyl)amino)-7-(pyridin-3-ylmethoxy) compound 25 showed selective DNA-PK inhibition. 2-morpholino-8-substituted-benzoxazine 9 (8-ph) and 1012 (8-(pyridine-2-, 3-, or 4-ylmethoxy) showed high-to-moderate inhibition of PI3K and DNA-PK. A similar pattern for DNA-PK nonselectivity over PI3K was observed for compounds with 7,8-O-bis-substituted 8a, 8c, and 8d. No DNA-PK selectivity over PI3K was observed regardless whether the substitution was phenyl, pyridin-2-ylmethoxy, pyridin-3-ylmethoxy, and pyridin-4-ylmethoxy.  相似文献   
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The study was conducted to assess the impact of combined interventions to improve the child immunization coverage in rural hard-to-reach areas of Bangladesh. The valid coverage increased at endline compared to baseline in the study areas, and the difference of the increase was highly significant (p < 0.001). The findings also showed that the number of drop-outs, left-outs, and invalid doses decreased at endline compared to baseline in the study areas, and the difference was also highly significant (p < 0.001). The immunization coverage improved significantly in all the four study sub-districts that received interventions, although the relative contribution of each intervention is unknown. The interventions can be implemented in all other hard-to-reach areas of Bangladesh and other countries which are facing similar challenges.  相似文献   
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Background and study aimsThere is lack of literature describing the presentation of diverticulitis in the Middle East population. The aim of this study is to provide an analysis of the epidemiological indicators, patterns of presentation and outcomes of acute diverticulitis in a Middle Eastern population.Patients and methodsA retrospective review of all adult patients over the age of 17 who were admitted to the surgical service with a diagnosis of acute diverticulitis between January 2010 and May 2018 at a major university affiliated government hospital in the state of Kuwait. Data collected included patients’ demographics, clinical presentation, management and outcome.ResultsBetween January 2010 and May 2018 there were 132 patients admitted with a diagnosis of acute diverticulitis. The mean age was 49.2 [±14.3] years. There were 89 (67.4%) men and 43 (32.6%) women. One-hundred and fifteen patients (87.1%) were Arabs, of which Kuwaiti citizens represented 58.3%. Most patients (76.5%) presented with uncomplicated diverticulitis. One hundred and twelve patients (84.8%) had sigmoid colon diverticulitis. There were nine patients that were readmitted within thirty days. The mean length of hospital stay was 5.3 days [±4.5]. The median follow-up period was 15.6 weeks (IQR 1.8, 118.4), during which time recurrent attacks occurred in 25 patients (18.9%).ConclusionsIt appears that there is a low prevalence of acute diverticulitis in Arabs living in Kuwait, and that when they do present with acute diverticulitis the majority present at a relatively younger age with uncomplicated disease.  相似文献   
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