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941.
Zingiber zerumbet rhizome has been used in traditional medicine mainly for the treatment of various immune‐inflammatory related ailments and has been shown to exhibit a wide spectrum of biological effects especially antioxidant and anti‐inflammatory activities. The present study was aimed to investigate the immunosuppressive effects of the standardized 80% ethanol extract of Z. zerumbet at 100, 200, and 400 mg/kg on the innate immune responses in male Wistar rats. The immune parameters determined were chemotaxis of neutrophils, Mac‐1 expression, engulfment of Escherichia coli by neutrophils, reactive oxygen species production, and plasma lysozyme and ceruloplasmin levels. Zerumbone was qualitatively and quantitatively determined in the extract by using a validated reversed‐phase HPLC, whereas liquid chromatography tandem‐mass spectrometry (LC ‐MS/MS) was used to profile the secondary metabolites. Z. zerumbet significantly inhibited the migration of neutrophils, expressions of CD11b/CD18 integrin, phagocytic activity, and production of reactive oxygen species in a dose‐dependent manner. The extract also dose‐dependently inhibited the expressions of lysozyme and ceruloplasmin in the rat plasma. Z. zerumbet extract possessed strong inhibitory effects on the innate immune responses and has potential to be developed into an effective immunosuppressive agent.  相似文献   
942.
For estimating behavioral hearing thresholds, auditory steady state response (ASSR) can be reliably evoked by stimuli at low and high modulation frequencies (MFs). In this regard, little is known regarding ASSR thresholds evoked by stimuli at different MFs in female and male participants. In fact, recent data suggest that 40-Hz ASSR is influenced by estrogen level in females. Hence, the aim of the present study was to determine the effect of gender and MF on ASSR thresholds in young adults. Twenty-eight normally hearing participants (14 males and 14 females) were enrolled in this study. For each subject, ASSR thresholds were recorded with narrow-band chirps at 500, 1,000, 2,000, and 4,000 Hz carrier frequencies (CFs) and at 40 and 90 Hz MFs. Two-way mixed ANOVA (with gender and MF as the factors) revealed no significant interaction effect between factors at all CFs (p > 0.05). The gender effect was only significant at 500 Hz CF (p < 0.05). At 500 and 1,000 Hz CFs, mean ASSR thresholds were significantly lower at 40 Hz MF than at 90 Hz MF (p < 0.05). Interestingly, at 2,000 and 4,000 Hz CFs, mean ASSR thresholds were significantly lower at 90 Hz MF than at 40 Hz MF (p < 0.05). The lower ASSR thresholds in females might be due to hormonal influence. When recording ASSR thresholds at low MF, we suggest the use of gender-specific normative data so that more valid comparisons can be made, particularly at 500 Hz CF.  相似文献   
943.
944.
Objective Only 9 % of women with young children consume a high quality diet. The association between sleep duration and health may be U-shaped. We examined diet quality in relation to sleep duration among US women within 5 years of childbirth. Methods Data were from non-pregnant women aged 20–44 years within 5 years of childbirth who completed two 24-h dietary recalls (N = 896) in the National Health and Nutrition Examination Survey 2005–2012. Self-reported weekday/workday sleep duration was categorized as short (≤6 h), adequate (7–8 h), or long (≥9 h). The Healthy Eating Index (HEI-2010, range 0–100) estimated overall and components of diet quality. Multivariable-adjusted linear regression models estimated the association between sleep duration and diet quality, adjusting for age, race/ethnicity, and education. Results Thirty-four percent of women reported short, 57.1 % adequate, and 8.6 % long sleep duration. The average diet quality total score was 47.4 out of 100. Short sleep duration was not associated with diet quality. Long sleep duration was associated with lower quality diet (β = ?4.3; 95 % CI ?8.1 to ?0.4), lower consumption of total fruit (β = ?0.7; 95 % CI ?1.3 to ?0.1), whole fruit (β = ?0.9; 95 % CI ?1.6 to ?0.2), and total protein (β = ?0.7; 95 % CI ?1.3 to ?0.03), and higher consumption of empty calories (β = 2.2; 95 % CI ?4.3 to ?0.1). Conclusions for practice Future studies should examine the longitudinal association between sleep duration and diet quality among women following childbirth and whether interventions to improve sleep can enhance diet quality.  相似文献   
945.
Abstract – Both length of extra-alveolar time and type of storage media are significant factors that can affect the long-term prognosis for replanted teeth. Numerous studies have examined various media in an attempt to determine the ideal material for storage of the avulsed tooth. The purpose of this study was to compare the number of viable periodontium ligament (PDL) cells in different storage media using a collagenase assay. Thirty-three freshly extracted human teeth were divided into four experimental and two control groups. The positive and negative controls corresponded to 0 min and an 8-h dry time, respectively. The experimental teeth were stored dry for 30 min and then immersed in one of four media (Hank's balanced salt solution (HBSS), milk, saline, water) for 45 min. The teeth were then treated with dispase grade II and collagenase for 30 min. The number of viable and nonviable PDL cells was counted with a hemocytometer and analyzed. An anova demonstrated no statistically significant differences in the viability of PDL cells among saline, HBSS and milk. Within the parameters of this study, it appears that milk or saline is an equally viable alternative to HBSS for storage of avulsed teeth.  相似文献   
946.
The fluoride content in surface enamel and its relationship to caries experience was studied in a group of Icelandic schoolchildren living in a low-fluoride area. Fluoride content was assessed by means of in vivo enamel biopsies sampled from 248 subjects aged 11 and 12 years. Dental examinations were performed in conjunction with the biopsy sampling and by the same examiner 1 year later. The prevalence and incidence of initial (DSI) and manifest (DFS) caries lesions were recorded separately. A median fluoride concentration of 610 ppm at a median biopsy depth of 4.2 microns was observed. A significant positive correlation was found between DSI and enamel fluoride content in girls and all older children. Additionally, surface enamel fluoride was measured in 72 Swedish children from a low-fluoride area but exposed to regular topical fluoride treatments. The difference in mean fluoride concentrations between the Icelandic and Swedish study populations was highly significant. From the measured fluoride concentrations the enamel fluoride profiles for both study populations were constructed. The differences in fluoride content were most pronounced in the outermost layer, apparently reflecting the higher exposure to and acquisition of topical fluoride in the Swedish children.  相似文献   
947.
Oral manifestations in 22q11 deletion syndrome   总被引:2,自引:0,他引:2  
Summary. Objectives. The aims of this study were to investigate and describe oral manifestations in 22q11 deletion syndrome, and to relate the findings to medical conditions. Design. Cross‐sectional. Sample and Methods. Fifty‐three consecutive patients from Sweden referred to the Sahlgrenska University Hospital during a 3‐year period were included, median age 8 yrs (range 2–43; mean age 11·09). All but six patients were children 3–19‐years‐old. The patients were examined concerning oral mucosa, dental anomalies, dental caries, occlusal development, and eruption of the teeth. The clinical findings were compared to medical data and case history. Results. Dental anomalies were registered in high numbers. Enamel hypoplasia was found in 16 patients. In 13 cases this was documented in primary teeth, of which 10 patients had symmetrical and chronological defects. Enamel hypomineralization was found in 23 patients and was equally common in both primary and permanent teeth. The use of computerized inductive analyses revealed that enamel hypoplasia was associated with medical conditions like preterm birth and congenital heart malformation while hypomineralization was associated with more diffuse conditions like frequent infections. Hypodontia was registered in seven patients, while eight had aberrant tooth shape, and nine patients presented delayed tooth eruption. The patients had an average of 4·6 carious or filled teeth and the oral health was assessed as impaired in 15 patients who had severe dental caries (5–18 carious teeth or multiple active incipient caries lesions). Conclusions. In 22q11 deletion syndrome the oral cavity is affected by anomalies in dental enamel, tooth shape, numbers of teeth, and eruption. Dental health problems due to caries are common. This is of special importance as patients with 22q11 deletion syndrome frequently present with congenital heart malformations and immunological problems.  相似文献   
948.
OBJECTIVE: To investigate anatomical variations and abnormalities of cervical spine morphology in unoperated infants with cleft lip and palate. DESIGN: Retrospective cross-sectional investigation of infants born with nonsyndromic cleft lip and palate using computed tomography scans acquired for investigation of a spectrum of clinical conditions. SETTING: Computed tomography scan data were obtained from 29 unoperated cleft lip and palate infants and 12 noncleft infants of Malay origin, ages 0 to 12 months. METHODS: Observational study of cervical spine computed tomography scans. Heights of cervical vertebral bodies (C2-C7) and intervertebral spaces were measured from landmarks identified from computed tomography reformats and three-dimensional computed tomography reconstructions. Linear modeling of heights and spaces, with age as a covariate, was undertaken to identify differences between the samples. RESULTS: Anomalous features observed in the cleft lip and palate sample included short posterior arch of C1 (2/29), abnormal development of the anterior arch of C1 (2/29), and fusions of the posterior arch of C2 and C3 (2/29). No anomalies of the cervical spine were observed in the noncleft sample. Although the heights of three cervical vertebral bodies were significantly smaller and two intervertebral spaces were significantly larger in infants with cleft lip and palate compared with noncleft infants (p < .05), overall length of the cervical spine did not differ significantly between the samples. CONCLUSION: There was evidence for subtle upper spinal anomalies in the infant cleft lip and palate population. Our finding of reduced size of some cervical vertebral bodies may reflect delayed upper spinal development in infants with cleft lip and palate.  相似文献   
949.
Molecular epidemiology of tuberculosis in Malaysia   总被引:6,自引:0,他引:6       下载免费PDF全文
Molecular typing with IS6110 was applied to Mycobacterium tuberculosis isolates from all parts of Malaysia. The degree of clustering increased with patient age, suggesting that reactivation may contribute to clustering. Identical banding patterns were also obtained for isolates from widely separate regions. Therefore, the use of clustering as a measure of recent transmission must be treated with caution. Strains related to the Beijing family were common in Peninsular Malaysia but were less common in Sabah and Sarawak, while a distinct group of strains comprised nearly 40% of isolates from East Malaysia but such strains were rare in Peninsular Malaysia. Single-copy strains, common in South and Southeastern Asia, constituted nearly 20% of isolates from the peninsula but were virtually absent in East Malaysia. The marked geographical difference in the prevailing strains indicates not only a restricted dissemination of M. tuberculosis but also a considerable degree of stability in the banding patterns.  相似文献   
950.
Structure‐based virtual screening (SBVS) has served as a popular strategy for rational drug discovery. In this study, we aimed to discover novel benzopyran‐based inhibitors that targeted the NS3 enzymes (NS3/4A protease and NS3 helicase) of HCV G3 using a combination of in silico and in vitro approaches. With the aid of SBVS, six novel compounds were discovered to inhibit HCV G3 NS3/4A protease and two phytochemicals (ellagic acid and myricetin) were identified as dual‐target inhibitors that inhibited both NS3/4A protease and NS3 helicase in vitro (IC50 = 40.37 ± 5.47 nm and 6.58 ± 0.99 µm , respectively). Inhibitory activities against the replication of HCV G3 replicons were further assessed in a cell‐based system with four compounds showed dose‐dependent inhibition. Compound P8 was determined to be the most potent compound from the cell‐based assay with an EC50 of 19.05 µm . The dual‐target inhibitor, ellagic acid, was determined as the second most potent (EC50 = 32.37 µm ) and the most selective in its inhibitory activity against the replication of HCV replicons, without severely affecting the viability of the host cells (selectivity index > 6.18).  相似文献   
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