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1.
We investigated the effects of 12‐hour shift work for five to seven consecutive days and overtime on the prevalence of severe sleepiness in the automobile industry in Korea. [Correction added after online publication 28 Nov: Opening sentence of the summary has been rephrased for better clarity.] A total of 288 randomly selected male workers from two automobile factories were selected and investigated using questionnaires and sleep‐wake diaries in South Korea. The prevalence of severe sleepiness at work [i.e. Karolinska Sleepiness Scale (KSS) score of 7 or higher] was modeled using marginal logistic regression and included theoretical risk factors related to working hours and potential confounding factors related to socio‐economic status, work demands, and health behaviors. Factors related to working hours increased the risk for severe sleepiness at the end of the shift in the following order: the night shift [odds ratio (OR): 4.7; 95% confidence interval (CI): 3.6–6.0)], daily overtime (OR: 2.2; 95% CI: 1.7–2.9), weekly overtime (OR: 1.6; 95% CI: 1.0–2.6), and night overtime (OR: 1.6; 95% CI: 0.8–3.0). Long working hours and shift work had a significant interactive effect for severe sleepiness at work. Night shift workers who worked for 12 h or more a day were exposed to a risk of severe sleepiness that was 7.5 times greater than day shift workers who worked less than 11 h. Night shifts and long working hours were the main risk factors for severe sleepiness among automobile factory workers in Korea. Night shifts and long working hours have a high degree of interactive effects resulting in severe sleepiness at work, which highlight the need for immediate measures to address these characteristics among South Korean labor force patterns.  相似文献   
2.
Certain patients have a tendency for high response to gonadotrophin therapy which is often not ameliorated with prior gonadotrophin- releasing hormone agonist (GnRHa) suppression. As a result, these patients are frequently cancelled and often experience ovarian hyperstimulation syndrome (OHSS) episodes during in-vitro fertilization (IVF)-embryo transfer cycles. Patients with polycystic ovarian syndrome (PCOS) have been noted to be particularly sensitive to exogenous gonadotrophin therapy. We have developed a protocol which is effective in improving IVF outcome in high responder patients, including those with PCOS. Oral contraceptive pills (OCP) are taken for 25 days followed by s.c. leuprolide acetate, 1 mg/day, which is overlapped with the final 5 days of oral contraceptive administration. Low-dose gonadotrophin stimulation is then initiated on the third day of withdrawal bleeding in the form of either human menopausal gonadotrophins or purified urinary follicle-stimulating hormone at a dosage of 150 IU/day. Over a 5 year period, we reviewed our experience utilizing this dual method of suppression in 99 cycles obtained in 73 high responder patients. There were only 13 cancellations prior to embryo transfer (13.1%). The clinical and ongoing pregnancy rates per initiated cycle were 46.5 and 40.4% respectively. Only eight patients experienced mild-moderate OHSS following treatment. For those patients who had undergone previous IVF-embryo transfer cycles at our centre, significant improvements were noted in oocyte fertilization rates, embryo implantation rates and clinical/ongoing pregnancy rates with this protocol. Hormonal analyses revealed that the chief mechanism may be through an improved luteinizing hormone/follicle-stimulating hormone ratio following dual suppression. An additional feature of this dual method of suppression is significantly lower serum androgen concentrations, particularly dehydroepiandrosterone sulphate.   相似文献   
3.
A school-based study was implemented to assess the family history of coronary heart disease (CHD) and hyperlipidemia (HL) in relation to serum lipoprotein and apolipoprotein levels. One hundred and twenty-five elementary school students (aged9–10 years) and 297 junior high school students (aged12–13 years) participated. Family history was evaluated by the following scoring method: positive family history in a parent. 2 points: in a grandparent. 1 point: and onset of CHD before age 60, 1 additional point. Family history of HL was positive in 8.2% of elementary school students, and 4.2% in junior high school students. Family history of CHD was positive in 11.5% of elementary students, and 11.0% in junior students. Family history score (FHS) for HL was related to serum total cholesterol (TC), low density lipoprotein cholesterol (LDLC), high density lipoprotein cholesterol, apolipoprotein A-T, apolipoprotein B (apoB) and lipoprotein (a) in elementary students, and to TC, LDLC, triglyceride and apoB in junior students. There was no relationship between FHS for CHD and serum lipoprotein or apolipoprotein levels in any student. The children with a positive FH of HL already demonstrated an atherogenic lipid profile while those with FH of CHD did not. which was probably because lipid profiles in children are more genetically mediated by a FH of HL than of CHD.  相似文献   
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5.
Summary. Sixty human premolar and canine teeth were used in this study. Class V cavities were prepared with a turbine handpiece. The experimental material was ASPA, with silicate cement and zinc oxide-eugenol cements being used as controls. The teeth were extracted approximately 4 days, 30 days or 90 days after insertion of the filling material. They were demineralized and prepared for histological examination. The test procedure and evaluation closely followed recommendations by the FDI (1980). The reaction at the short time interval for each material was similar, while at the intermediate and long periods silicate cement caused the most inflammation, zinc oxideeugenol cement the least, and ASPA an intermediate response. The reaction to ASPA was reduced at the long period compared with the intermediate period.  相似文献   
6.
星形胶质细胞在突触形成中发挥重要作用,但星形胶质细胞突起如何在发育过程中与突触结构相联系还不是很清楚。本文分析在小脑突触发生过程中Bergmann胶质细胞(BG)突起生长的类型。本文发现在这个过程中,BG突起向外生长与树突棘增多的包被作用相关。此外,双光子时间分辩显像显示BG突起是高度动态的,在棘包被过程中突起趋于稳定。虽然突触活力依赖于肌动蛋白的聚合作用,但细胞骨架调节器Rac1和RhoG的活动在胶质细胞突起的动力或密度上并未发挥作用,而是对于保持突起长度起关键性作用。本文扩展这个发现,探查突起形态和包被之间的关系,发现缩短的突起导致棘覆盖的减少。本文进一步发现在BG表达dn-Rac1和低水平突触包被的区域,显示突触数量的增加。这些分析提示BG突起如何生长并包围突触结构,阐明BG突起结构对突触包被适当发育的重要性,并提示包被在突触形成中的作用。  相似文献   
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8.

Background

Pirfenidone is a novel anti-fibrotic agent in idiopathic pulmonary fibrosis with proven clinical benefit. Better human tissue models to demonstrate the immunomodulatory and anti-fibrotic effect of pirfenidone are required.

Objectives

The purpose of the study was to use transbronchial lung cryobiopsy (TBLC), a novel technique which provides substantial tissue samples, and a large panel of biomarkers to temporally assess disease activity and response to pirfenidone therapy.

Methods

Thirteen patients with confirmed idiopathic pulmonary fibrosis (IPF) underwent full physiological and radiological assessment at diagnosis and after 6-month pirfenidone therapy. They underwent assessment for a wide range of potential serum and bronchoalveolar lavage biomarkers of disease activity. Finally, they underwent TBLC before and after treatment. Tissue samples were assessed for numbers of fibroblast foci, for Ki-67, a marker of tissue proliferation and caspase-3, a marker of tissue apoptosis.

Results

All patients completed treatment and investigations without significant incident. There was no significant fall in number of fibroblast foci per unit tissue volume after treatment (pre-treatment: 0.14/mm2 vs. post-treatment 0.08/mm2, p?=?0.1). Likewise, there was no significant change in other markers of tissue proliferation, Ki-67 or Caspase-3 with pirfenidone treatment. We found an increase in three bronchoalveolar lavage angiogenesis cytokines, Placental Growth Factor, Vascular Endothelial Growth Factor-A, and basic Fibroblast Growth Factor, two anti-inflammatory cytokines Interleukin-10 and Interleukin-4 and Surfactant Protein-D.

Conclusions

TBLC offers a unique opportunity to potentially assess the course of disease activity and response to novel anti-fibrotic activity in IPF.
  相似文献   
9.
Tryptophan (TRP), the precursor of the scavenger or immunomodulator molecules melatonin (MLT) and picolinic acid, can be found in the diet; and could be an alternative nutritional supplement used to regulate the immune response in the generation of free radicals. In an experimental model, the systemic administration of lipopolysaccharide (LPS), to promote the synthesis of pro-inflammatory cytokines, reactive oxygen species, and antioxidant enzymes, was performed on adult female, pregnant and lactating rats fed with a diet of TRP content (0.5 mg/100 g protein). Lung tissue was evaluated for levels of the products of lipoperoxidation (LPO's), malonaldehyde (MDA) and 4-hydroxy alkenals (4-HDA); nitrites (NO2), glutathione peroxidase (Gpx) enzyme activity, and the serum concentration of interferon-gamma (IFN-γ), which were measured in the following groups: control (CTRL), LPS, MLT, TRP, LPS plus MLT (LPS + MLT), and LPS plus TRP (LPS + TRP). Results showed that the lung tissue levels of MDA and 4-HDA in the LPS + TRP group were significantly lower than in the TRP group. Statistically significant differences were not observed in nitric oxide levels among the groups LPS + MLT and LPS + TRP compared to the group under endotoxic shock (LPS). The Gpx enzyme activity was modified in the LPS + MLT vs the LPS group, but the difference was not statistically significant. The LPS + MLT group showed a smaller serum concentration (98%) of IFN-γ than the LPS group. Statistically significant differences were not observed among the animals of the LPS + TRP and the LPS groups.  相似文献   
10.
Potent JNK3 isoform selective inhibitors were developed from a thiophenyl-pyrazolourea scaffold. Through structure activity relationship (SAR) studies utilizing enzymatic and cell-based assays, and in vitro and in vivo drug metabolism and pharmacokinetic (DMPK) studies, potent and highly selective JNK3 inhibitors with oral bioavailability and brain penetrant capability were developed. Inhibitor 17 was a potent and isoform selective JNK3 inhibitor (IC50 = 35 nM), had significant inhibition to only JNK3 in a panel profiling of 374 wild-type kinases, had high potency in functional cell-based assays, had high stability in human liver microsome (t1/2 = 66 min) and a clean CYP-450 inhibition profile, and was orally bioavailable and brain penetrant. Moreover, cocrystal structures of compounds 17 and 27 in human JNK3 were solved at 1.84 Å, which showed that these JNK3 isoform selective inhibitors bound to the ATP pocket, had interactions in both hydrophobic pocket-I and hydrophobic pocket-II.  相似文献   
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