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21.
BackgroundLow serum magnesium levels predict cardiovascular and all-cause mortality in patients with typ 2 diabetes.SettingOutpatient clinic of obesity and central hospital.ObjectivesTo assess long-term alterations in circulating magnesium status after Roux-en-Y gastric bypass (RYGB) surgery and associations with remission of type 2 diabetes (T2D).MethodsRetrospective analysis of 5-year outcomes of plasma magnesium (p-Mg) and glucometabolic statuses in patients who underwent primary RYGB and who completed the annual follow-up program. Data were investigated from 84 patients without diabetes and 62 with T2D before RYGB, who showed either prolonged remission (n = 30), temporary remission (n = 16), or no remission (n = 16) after surgery.ResultsBody mass indexes before RYGB were similar in patients with and without T2D, irrespective of remission. The patients not achieving remission showed longer diabetes durations; higher circulating glucose levels; more intensive antidiabetic drug treatment, including insulin; and significantly lower p-Mg concentrations (.73 [±.08] mmol/L compared with .80–.82 [±.07] mmol/L, respectively; P < .01) than the groups showing remission or without diabetes before surgery. After RYGB, the p-Mg increased similarly, by 10–12% in the groups with T2D before surgery, irrespective of remission; however, the nonremission group did not reach the p-Mg levels registered in the other groups after follow-up. The nonremission group reached .82 (.09) mmol/L, compared with .87 (.06) and .88 (.08) mmol/L (P < .05), respectively, in patients with remission or without a history of diabetes.ConclusionThe p-Mg concentrations increased after RYGB, with similar increments irrespective of T2D remission; however, the nonremission group started from an inferior level and did not reach the p-Mg concentrations seen in the groups achieving remission or without a history of diabetes before surgery.  相似文献   
22.
4 workers developed hand and face dermatitis when exposed to a floor top coal. This contained a polyurethane arid a polyfunctional aziridine hardener and additives. The aziridine hardener was made by reacting propyleneimine with a polyfunctional acrylate, trimethylolpropane triacrylate (TMPTA). All 4 reacted to the hardener and to TMPTA, which is present in excess, 2 of them also reacted to pentacrythritol triacrylate (PETA), which can be used in the production of aziridine hardeners. TMPTA and PETA cross-react, and are known sensitizers in UV-hardening acrylates.
The present finding shows that well-known sensitizers can be found in hidden sources when used in a quite different chemical process.  相似文献   
23.
Following superior cervical ganglionectomy the noradrenaline tissue levels in the base of the rabbit external ear started to decrease after about 12 hours. About 4 hours later noradrenaline started to decrease about simultaneously in the middle piece and the tip. Within 24 hours after ganglionectomy the noradrenaline decreased rapidly in all three pieces. Thereafter the noradrenaline of the base piece was levelling off at about 15% of the normal whereas the noradrenaline in the two other pieces remained at about 40% of the normal. The results indicate that the adrenergic innervation of the ear is complex, but that the base piece is supplied with adrenergic axons that are shorter than those of the middle and tip pieces. Based on 1: the delay of 4 hours observed in the pattern of the noradrenaline disappearance between the base and the two other pieces, and II: the difference in distance between the three pieces of the ear and the superior cervical ganglion, a transport rate of a "protecting factor" could be discussed to be about 1-2 cm/h. The rate of axonal transport of dopamine-beta-hydroxylase in the rabbit sciatic nerve, was found to be within the same range, being about 2 cm/h.  相似文献   
24.
AIMS: Certain phytoestrogens, such as lignans, may protect against developing breast cancer. Enterolactone is a lignan metabolite produced by the intestinal flora from dietary precursors such as whole grains, vegetables, and fruits. Enterolactone has been shown to have weak estrogenic and antiestrogenic properties. We decided to examine the association between plasma levels of enterolactone and mammographic density, a biomarker for breast cancer risk. METHODS: We included data from postmenopausal women ages 55 and older who participated in a cross-sectional mammogram study in Troms?, Norway. Mammograms, plasma enterolactone measurements, as well as information on anthropometric and hormonal/reproduction factors were available on 616 women. We assessed mammographic density using a previously validated computer-assisted method. We estimated correlation coefficients and conducted multiple regression analyses. RESULTS: Mean mammographic density increased slightly across quartiles of enterolactone; the women in the highest quartile had, on average, 3.1% (absolute difference) higher percentage mammographic density compared with the lowest quartile (P(trend) < 0.01). After adjustment for age, body mass index, number of full-term pregnancies, age at first birth, and use of postmenopausal hormone therapy, the mean difference in density was reduced to 2.0% (P(trend) = 0.05). Results were similar when restricted to the 454 current hormone nonusers. The fully adjusted statistical model explained 28.3% of the total variability in mammographic percentage density, with body mass index contributing 18.2% and enterolactone only 0.9%. CONCLUSION: In our study, higher levels of enterolactone were associated with slightly higher percentage mammographic density. Our results suggest that if higher enterolactone levels reduce the risk of developing breast cancer in postmenopausal women, then this effect is not through lowering mammographic density.  相似文献   
25.
CYP2C9-dependent drug metabolism is subject to large interindividual variation. To some extent, this is explained by genetic polymorphism with expression of enzyme variants that differ in catalytic activity. The aim of this study was to characterize the variation in CYP2C9 phenotype in relation to genotype, with further analysis of the CYP2C9 gene in metabolic outliers. A study population of 126 healthy white subjects were recruited and genotyped for the variant alleles, CYP2C9*1-3. In CYP2C9 phenotyping with losartan, three subpopulations were distinguished that differed in the number of CYP2C9*3 alleles (0, 1, or 2). A three-fold higher metabolic ratio (MR; urinary losartan/carboxymetabolite) was found comparing CYP2C9*1/*3 (n = 20) to CYP2C9*1/*1 (n = 81), but there was considerable variation within each genotype. Subjects genotyped as CYP2C9*1/*1, but with an unexpectedly slow oxidation of losartan, were selected for DNA-sequencing analysis of the CYP2C9 gene. Interestingly, single nucleotide polymorphisms (SNPs) could not be identified either in the 5'-flanking region, the nine exons, or exon-intron boundaries. However, sequencing of the CYP2C9 gene was also carried out in patients genotyped as CYP2C9*1/*1 but with an exceptionally low steady-state clearance of S-warfarin. Here, five different SNPs were identified. In further analysis of the healthy volunteers, it became evident that women on oral contraceptives (OCs) had slower oxidation of losartan (MR of losartan: 1.7) than women without OCs (MR of losartan: 0.86). This novel finding was not explained by a different frequency of variant alleles. In summary, CYP2C9 genotype and oral contraceptives both contribute to a large interindividual variation in CYP2C9 activity.  相似文献   
26.
The interrelation between the development of the brain/peripheral nerves and that of the surrounding bone tissue is termed neuro-osteology. In orthodontic and pediatric practice the development of the hard tissues is evaluated radiographically, but the development of the neural tissue within the bone tissue is not evaluated. In this review the emphasis is placed on two neuro-osteologic interrelations that can be observed on profile radiographs and orthopantomograms, respectively. One is the connection between the pituitary gland of the central nervous system and the sella turcica (profile radiograph), and the other is the association between the peripheral nerves and the development of the dentition (orthopantomogram). Pituitary gland/sella turcica: The correlation between prenatal malformation in the pituitary gland/sella turcica and the postnatal morphology of the sella turcica in holoprosencephaly, spina bifida/myelomeningocele, and cri-du-chat syndrome is demonstrated. Peripheral nerves/dentition: The prenatal innervation of the dentition is presented. Agenesis and tooth malformation occur in constant patterns within the dental arch fields that share the same innervation. The findings demonstrate that in postnatal diagnosis of the cranium and the teeth, traces of prenatal aberrations can be found that are important for neurofacial growth.  相似文献   
27.
Malassez epithelium has been designated as epithelial cell rests, the biological significance of which is still under debate. This study was designed to analyze Malassez epithelium for the presence of neuroendocrine cells. Gingival tissue was included as a positive control. Using immunohistochemistry, confocal and light microscopy, Malassez epithelium and gingival epithelium from mature cats (n=5) were examined for cells containing the neuropeptides calcitonin gene-related peptide (CGRP), substance P (SP), and vasoactive intestinal peptide (VIP). Both Malassez epithelium and the basal epithelial cell layers in gingival rete pegs regularly displayed cells immunoreactive to CGRP, SP, and VIP. The immunopositive cells were most frequently present in the epithelial cell clusters and strands of Malassez located in the cervical half of the periodontal ligament. Double immunolabeling revealed cellular co-expression of CGRP or SP with VIP, and the neuropeptides were co-localized in the cellular compartments. Labeled cells in both epithelia were occasionally supported by immunoreactive nerve fibers. This study shows that cells immunoreactive to CGRP, SP, and VIP are located within the cat Malassez epithelium. The localization of neuroendocrine cells verifies the diversity of this epithelium and confirms that Malassez epithelium is composed of different cell types, in common with epithelia from other locations. The presence of neuroendocrine cells in Malassez epithelium strongly suggests biological functions of this tissue, and the neuropeptide content may thus indicate endocrine functions of the cells.  相似文献   
28.
29.
In this study we examine the longitudinal effects of psychiatric and substance use disorders on employment, in an employed population. The sample included respondents to the National epidemiologic survey on alcohol related conditions (NESARC) who were employed at Wave 1 (N = 22,407). Bivariate and multivariable analyses were conducted examining the associations between 12-month and new onset 12-month psychiatric diagnoses at Wave 1 and employment status at Wave 2. Past year and new onset 12-month depression, 12-month bipolar, new onset 12-month drug abuse, and 12-month and new onset 12-month drug dependence were associated with a decreased odds of being employed at Wave 2. This study suggests that it would be beneficial for employers to support their employees in participating in mental health treatment. Additionally, understanding how psychiatric disorders influence employment over the life course might inform the development of preemptive interventions to treat mental health symptoms.  相似文献   
30.
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