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排序方式: 共有3113条查询结果,搜索用时 15 毫秒
1.
Eun-Joo Shin Yunsung Nam Thu-Hien Thi Tu Yong Kwang Lim Myung-Bok Wie Dae-Joong Kim Ji Hoon Jeong Hyoung-Chun Kim 《Archives of toxicology》2016,90(4):937-953
We investigated whether protein kinase C (PKC) is involved in trimethyltin (TMT)-induced neurotoxicity. TMT treatment (2.8 mg/kg, i.p.) significantly increased PKCδ expression out of PKC isozymes (i.e., α, βI, βII, δ, and ?) in the hippocampus of wild-type (WT) mice. Consistently, treatment with TMT resulted in significant increases in cleaved PKCδ expression. Genetic or pharmacological inhibition (PKCδ knockout or rottlerin) was less susceptible to TMT-induced seizures than WT mice. TMT treatment increased glutathione oxidation, lipid peroxidation, protein oxidation, and levels of reactive oxygen species. These effects were more pronounced in the WT mice than in PKCδ knockout mice. In addition, the ability of TMT to induce nuclear translocation of Nrf2, Nrf2 DNA-binding activity, and upregulation of γ-glutamylcysteine ligase was significantly increased in the PKCδ knockout mice and rottlerin (10 or 20 mg/kg, p.o. × 6)-treated WT mice. Furthermore, neuronal degeneration (as shown by nuclear chromatin clumping and TUNEL staining) in WT mice was most pronounced 2 days after TMT. At the same time, TMT-induced inhibition of phosphoinositol 3-kinase (PI3K)/Akt signaling was evident, thereby decreasing phospho-Bad, expression of Bcl-xL and Bcl-2, and the interaction between phospho-Bad and 14-3-3 protein, and increasing Bax expression and caspase-3 cleavage were observed. Rottlerin or PKCδ knockout significantly protected these changes in anti- and pro-apoptotic factors. Importantly, treatment of the PI3K inhibitor LY294002 (0.8 or 1.6 µg, i.c.v.) 4 h before TMT counteracted protective effects (i.e., Nrf-2-dependent glutathione induction and pro-survival phenomenon) of rottlerin. Therefore, our results suggest that down-regulation of PKCδ and up-regulations of Nrf2-dependent glutathione defense mechanism and PI3K/Akt signaling are critical for attenuating TMT neurotoxicity. 相似文献
2.
D. Thiébaud P. Burckhardt M. Costanza D. Sloutskis D. Gilliard F. Quinodoz A.-F. Jacquet B. Burnand 《Osteoporosis international》1997,7(5):457-462
The relative importance of vitamin D deficiency, secondary hyperparathyroidism, nutritional deficiency and low bone mineral
density (BMD) as risk factors for hip fracture is not definitely established. In the framework of a case-control study of
risk factors for hip fractured, biochemical markers of bone metabolism and nutrition and femoral BMD data were compared in
136 female and 43 male hip fracture patients, 126 female and 44 male age-matched hospitalized controls, and 47 healthy elderly
women (8 men). Patients with hip fracture had lower albumin (−10%9 and 25(OH)-vitamin D (25(OH)D; −19%) compared with hospitalized
controls, and lower albumin (−28%) and 25(OH)D levels (−52%) compared with the elderly controls. Serum values of IGFBP-3 were
also significantly lower (−33%) in hip fracture patients than in community controls. BMD of femoral neck was lower (p < 0.001) in patients than in hospitalized and community controls. In hip fracture patients, parathyroid hormone (PTH) correlated
weakly with BMD (neck: r = −0.19, trochanter: r = −0.17; both p < 0.05). When all women were pooled (n = 233), albumin correlated significantly (age-adjusted) with BMD at all sites (neck: r = 0.27, trochanter: r = 0.25; all p < 0.001). Albumin, but not 25(OH)D, also correlated with skinfold thickness (r = 0.19, p < 0.0025) and with body mass index (BMI) (r = 0.14, p < 0.05). Male patients with hip fracture had lower BMD and albumin (both p < 0.001), 25(OH)D (p = 0.02) and IGFBP-3 levels (p <: 0.005) compared with the controls. When male patients and controls were pooled together, albumin, skinfold thickness and
BMI were significantly correlated with each other, but not with BMD. IGFBP-3 was highly correlated with albumin (p < 0.0001), 25(OH)D (p < 0.005) and, less significantly, with PTH (p < 0.05), but not with BMI or skinfold thickness. IGFBP-3 was significantly correlated with BMD at all sites (neck: r = 0.27, p < 0.05); trochanter: r = 0.40, p < 0.0005). In conclusion, low albumin and low BMD were both important risk factors for hip fracture. Low serum albumin was
the strongest independent variable correlated with hip fractures. In men, IGFBP-3 was correlated with BMD. The femoral BMD
depended only weakly on PTH and 25(OH)D, but was correlated at all sites with albumin, a non-specific parameter of nutrition
and general health. 相似文献
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5.
William F Astle Vivian E Hill Anna L Ells Nguyen Thi Thanh Chi Elaine Martinovic 《Journal of AAPOS》2003,7(5):339-344
BACKGROUND: Congenital absence of the inferior rectus muscle is a rare cause of apparent inferior rectus palsy especially in the absence of associated cranial facial anomalies. METHODS: We report three cases of isolated congenital absence of the inferior rectus muscle and its successful surgical management. RESULTS: Failure of the normal embryologic development of the mesodermal complex around the eye can lead to agenesis of the extraocular muscles. In apparent palsies of the inferior rectus muscle and no definite cause, a high index of suspicion and orbital imaging can confirm the diagnosis of congenitally absent inferior rectus preoperatively. Surgical correction may involve inferior transposition of the horizontal rectus muscles. CONCLUSIONS: Although rare, congenital absence of the inferior rectus muscle is a possible cause of apparent inferior rectus muscle palsy particularly in the absence of another identifiable cause. Strabismus surgery in conjunction with intramuscular botulinum toxin injection can offer significant improvement in function and cosmesis of these patients. 相似文献
6.
We provide microscopic evidence that motile rod-shaped forms of Ramlibacter tataouinensis TTB310 are formed from dividing cyst-like cells. Careful estimation of the size of the two morphotypes was conducted using optical and transmission electron microscopy (TEM). The cyst-like cell was shown to be a sphere with a diameter Dc=850 nm. The rod-shaped form was a round-ended cylinder with length Lr=2.91 microm and diameter Dr=239 nm. The membrane area of the two morphotypes was the same. However, the formation of rods from cysts involved loss of two-thirds of the cell volume. TEM showed that, prior to division and transition into rods, cysts contained condensed cytoplasmic material. These results suggest that the morphological transition occurs by pure reshaping of cells. 相似文献
7.
Thi Thu Ha Hoang Carina Bengtsson Dac Cam Phung Mikael Srberg Marta Granstrm 《Clinical and Vaccine Immunology : CVI》2005,12(1):81-85
Helicobacter pylori-associated diseases, such as peptic ulcer and gastric cancer, are common in Vietnam, but the prevalence of the infection is largely unknown. A validated enzyme-linked immunosorbent assay was used for seroepidemiology with 971 samples from the general population, ages 0 to 88 years, with 546 samples from an urban population (Hanoi), and with 425 samples from a poor, rural province (Hatay). The overall seroprevalence of the infection was 746 per 1,000, with a prevalence of 788 per 1,000 in Hanoi and 692 per 1,000 in Hatay (P = 0.0007). The risk for infection in the rural area of Hatay was 40% lower than in the urban population of Hanoi, with the odds ratio being 0.59 (95% confidence interval, 0.43 to 0.81). The study shows that the prevalence of H. pylori infection is high in Vietnam and especially high in a large urban area, such as the city of Hanoi. 相似文献
8.
9.
J. Tamarelle A.C.M. Thiébaut B. de Barbeyrac C. Bébéar J. Ravel E. Delarocque-Astagneau 《Clinical microbiology and infection》2019,25(1):35-47
Background
The vaginal microbiota may modulate susceptibility to human papillomavirus (HPV), Chlamydia trachomatis, Neisseria gonorrhoeae and Mycoplasma genitalium infections. Persistent infection with a carcinogenic HPV is a prerequisite for cervical cancer, and C. trachomatis, N. gonorrheae and M. genitalium genital infections are all associated with pelvic inflammatory disease and subsequent infertility issues.Objectives
To evaluate the association between these infections and the vaginal microbiota.Data sources
The search was conducted on Medline and the Web of Science for articles published between 2000 and 2016.Study eligibility criteria
Inclusion criteria included a measure of association for vaginal microbiota and one of the considered STIs, female population, cohort, cross-sectional and interventional designs, and the use of PCR methods for pathogen detection.Methods
The vaginal microbiota was dichotomized into high-Lactobacillus vaginal microbiota (HL-VMB) and low-Lactobacillus vaginal microbiota (LL-VMB), using either Nugent score, Amsel's criteria, presence of clue cells or gene sequencing. A random effects model assuming heterogeneity among the studies was used for each STI considered.Results
The search yielded 1054 articles, of which 39 met the inclusion criteria. Measures of association with LL-VMB ranged from 0.6 (95% CI 0.3–1.2) to 2.8 (95% CI 0.3–28.0), 0.7 (95% CI 0.4–1.2) to 5.2 (95% CI 1.9–14.8), 0.8 (95% CI 0.5–1.4) to 3.8 (95% CI 0.4–36.2) and 0.4 (95% CI 0.1–1.5) to 6.1 (95% CI 2.0–18.5) for HPV, C. trachomatis, N. gonorrhoeae and M. genitalium infections, respectively.Conclusions
Although no clear trend for N. gonorrhoeae and M. genitalium infections could be detected, our results support a protective role of HL-VMB for HPV and C. trachomatis. Overall, these findings advocate for the use of high-resolution characterization methods for the vaginal microbiota and the need for longitudinal studies to lay the foundation for its integration in prevention and treatment strategies. 相似文献10.
Linda Wittkop Daniel Commenges Isabelle Pellegrin Dominique Breilh Didier Neau Denis Lacoste Jean-Luc Pellegrin Geneviève Chêne François Dabis Rodolphe Thiébaut 《BMC medical research methodology》2008,8(1):68