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31.
Duk-Shin Lee Tae-Hyun Kim Hana Park Ji-Eun Kim 《International journal of molecular sciences》2022,23(9)
Clasmatodendrosis is one of the irreversible astroglial degeneration, which is involved in seizure duration and its progression in the epileptic hippocampus. Although sustained heat shock protein 25 (HSP25) induction leads to this autophagic astroglial death, dysregulation of mitochondrial dynamics (aberrant mitochondrial elongation) is also involved in the pathogenesis in clasmatodendrosis. However, the underlying molecular mechanisms of accumulation of elongated mitochondria in clasmatodendritic astrocytes are elusive. In the present study, we found that clasmatodendritic astrocytes showed up-regulations of HSP25 expression, AKT serine (S) 473 and dynamin-related protein 1 (DRP1) S637 phosphorylations in the hippocampus of chronic epilepsy rats. 2-Cyano-3,12-dioxo-oleana-1,9(11)-dien-28-oic acid methyl ester (CDDO-Me; bardoxolone methyl or RTA 402) abrogated abnormal mitochondrial elongation by reducing HSP25 upregulation, AKT S473- and DRP1 S637 phosphorylations. Furthermore, HSP25 siRNA and 3-chloroacetyl-indole (3CAI, an AKT inhibitor) abolished AKT-DRP1-mediated mitochondrial elongation and attenuated clasmatodendrosis in CA1 astrocytes. These findings indicate that HSP25-AKT-mediated DRP1 S637 hyper-phosphorylation may lead to aberrant mitochondrial elongation, which may result in autophagic astroglial degeneration. Therefore, our findings suggest that the dysregulation of HSP25-AKT-DRP1-mediated mitochondrial dynamics may play an important role in clasmatodendrosis, which would have implications for the development of novel therapies against various neurological diseases related to astroglial degeneration. 相似文献
32.
Silicon - This paper presents recent progress in computational modeling on blend morphology of silicon nanowires (SiNWs) dispersed in a conjugated polymer poly(3-hexylthiophene) P3HT hybrid solar... 相似文献
33.
BACKGROUND: Most complications after lung lobectomy are related to pain, narcotic analgesia, and inactivity. When the operation is performed with the goal of minimizing postoperative pain, and when rapid restoration of activity and patient independence can be achieved, most postoperative complications can be obviated and early discharge can be attained. METHODS: Since March 1996, we have performed 10 consecutive elective major lung resections (8 lobectomies and 2 bilobectomies) for neoplastic (n = 8) and benign inflammatory (n = 2) lesions. Of the 10 patients, 4 were men and 6 were women ranging in age from 58 to 77 years (mean age, 66 years). Extensive preoperative patient and family education was provided in the surgeon's office. Same-day admission was followed by an oblique muscle-sparing minithoracotomy to access the chest cavity. A meticulous operation, with special attention to minimizing air leak and postoperative discomfort, was performed. Intercostal nerve cryolysis was used as the main method of analgesia. RESULTS: All patients underwent the planned operation through a minithoracotomy and were extubated in the operating room. All patients exhibited normal ipsilateral shoulder girdle mobility in the recovery room and none required intravenous narcotics after leaving this unit. All patients were out of bed the day of the operation. The chest tube was removed the night of the operation in 2 patients, the morning after the operation in 6 patients, and on the second postoperative day in 1 patient. One patient who was discharged with a Heimlich valve had this device removed in the office 4 days after the operation. After the chest tubes were removed, there were no instances of pneumothorax. All 10 patients were able to ambulate independently on the first postoperative day. Eight patients were discharged home the morning after the operation and 2 on the second postoperative day. None of the patients have required readmission related to their operation or have exhibited evidence of postthoracotomy pain syndrome. CONCLUSIONS: We have developed a clinical pathway based on patient education, meticulous minimally invasive operation, cryoanalgesia, and quick resumption of physical activity. Our preliminary experience with this approach has shown minimal morbidity, rapid restoration to preoperative status, and, for most patients, a 1-day hospital stay after major lung resection. 相似文献
34.
T Nieszporek F Kokot A Wiecek W Marcinkowski R Rudka J Trembecki 《Canadian Metallurgical Quarterly》1995,52(12):590-593
The study aimed to assess the influence of long-term rhu-EPO treatment on secretion of pancreatic polypeptide (PP) and gastrin. A total of 27 haemodialysed patients and nine healthy subjects were examined. Nine patients with uraemic anaemia were treated with rhu-EPO for 12 months (EPO group), while another nine patients did not receive rhu-EPO (non-EPO group), but were monitored biochemically and clinically as patients of the EPO group. The third group (HD) comparised nine haemodialysed patients with a haematocrit value > or = 30% without rhu-EPO therapy. In all subjects plasma levels of PP and gastrin were estimated before and after administration of a test meal. Patients of the EPO and non-EPO group were examined before and after 6 and 12 months of rhu-EPO therapy (EPO group) or clinical monitoring (non-EPO group) respectively, while only one test was performed in patients of the HD group and healthy subjects. Six months rhu-EPO therapy was followed by an decrease of basal plasma level of PP and increased response of gastrin to the test meal. After 12 months of rhu-EPO therapy basal plasma level of PP was still lower, the response of PP secretion to a test meal was higher, while that of gastrin secretion lower that the pretreatment ones. Our results suggest, that rhu-EPO treatment exerts effect on secretion of PP and gastrin. These alterations seem not to be related to improvement of the haematological status. 相似文献
35.
Salwan K. J. Al-Ani Raid A. Ismail Hana F. A. Al-Ta’ay 《Journal of Materials Science: Materials in Electronics》2006,17(10):819-824
Optoelectronic properties of CdS:In/Si anisotype heterojunction photodetector fabricated by depositing of polycrystalline
CdS and indium doped CdS films used thermal resistive technique on clean monocrystalline p-type silicon substrates are presented. The effect of In diffusion
temperature(T
d)in CdS layer on the optoelectronic characteristics of these devices has been studied. Two peaks situated at 650 and 800 nm
with values of 0.32 and 0.43 A/W, respectively, were observed in the responsivity plot. Other optoelectronics properties such
as detectivity, photovoltaic, and response time are also presented. 相似文献
36.
A total of 19 patients with active nephrolithiasis, 14 patients with non-active nephrolithiasis and 17 healthy subjects were examined under standardized intake of calcium, phosphorus, purine and protein. In patients with both active and non-active renal stone disease the following abnormalities were found: elevated plasma levels of PTH and osteocalcin, increased activity of the bone isozyme of alkaline phosphatase, low plasma levels of phosphate and increased urinary excretion of calcium and oxalic acid. These abnormalities were more marked in patients with active than non-active nephrolithiasis. No correlation was found between plasma PTH levels and parameters of bone turnover as well as calciuria and oxaluria. Results presented in this paper suggest that (a) Smith's criteria of active renal stone disease are of minor pathogenetic and therapeutic value and (b) patients with active nephrolithiasis differ from non-active renal stone formers by more elevated oxaluria and markers of bone turnover and more marked abnormalities in calcium-phosphate metabolism related parameters. 相似文献
37.
Nataša Pipenbaher Peter Lange Moeller Jan Dolinšek Mogens Jakobsen Hana Weingartl Avrelija Cencič 《International Dairy Journal》2009,19(3):166-171
Nitric oxide (NO) affects multiple gastrointestinal functions, including mucosal inflammation and antimicrobial activity. The aim of this study was to screen the ability of probiotic bacteria to stimulate NO production in porcine intestinal epithelial cells and macrophages in the presence and absence of interferon gamma (INF-γ). Production of NO in intestinal epithelium was stimulated by individual strains of lactobacilli without INF-γ priming. While none of the tested bifidobacteria were capable of inducing NO production, most constitutively secreted NO. Most tested strains induced a significant increase in NO production compared with the control cells in the macrophage cell line 3D4/21. Results support the protective role of the individual strains of the genera Lactobacillus and Bifidobacterium and may lead to new approaches for manipulating and regulating immune responses at the mucosal surfaces of the gastrointestinal tract. 相似文献
38.
H Karkoszka J Chudek P Strzelczyk A Wiecek H Schmidt-Gayk E Ritz F Kokot 《Canadian Metallurgical Quarterly》1998,13(8):2077-2080
BACKGROUND: It has been suggested that the vitamin D receptor (VDR) gene BsmI-polymorphism is a genetic determinant of bone metabolism. DESIGN: To test this hypothesis, the relationship between VDR genotypes, bone mineral density (baseline and after 18 months) and parameters of calcium metabolism and bone turnover were investigated prospectively in 88 haemodialysed patients not receiving active vitamin D metabolites. METHODS: Whole body, lumbar spine and femoral neck bone mineral density (BMD) were assessed by dual energy X-ray absorptiometry (DEXA). In addition calcium, phosphorus, 25(OH)D3, 1,25(OH)2D3, osteocalcin serum concentrations, alkaline phosphatase activity and intact 1,84 PTH levels were measured. RESULTS: VDR genotype BB, Bb and bb were found in 27, 49 and 24% of patients. Initial BMD (g/cm2) of whole body, lumbar spine and femoral neck did not differ between genotypes (whole body: BB 1.055 +/- 0.120, Bb 1.082 +/- 0.102, bb 1.128 +/- 0.120; lumbar spine: BB 1.075 +/- 0.199, Bb 1.079 +/- 0.185, bb 1.099 +/- 0.170; femoral neck: BB 0.808 +/- 0.160, Bb 0.862 +/- 0.127, bb 0.842 +/- 0.125; mean +/- SD), but the decrease of whole body and femoral neck BMD during 18 months was significantly (P < 0.02) different between the genotype groups (whole body: BB -0.048 +/- 0.028, Bb -0.031 +/- 0.029, bb -0.024 +/- 0.023; femoral neck BB -0.044 +/- 0.069, Bb -0.032 +/- 0.081, bb -0.012 +/- 0.029 g/cm2). CONCLUSION: This preliminary study suggests faster mineral loss in BB genotype of VDR in haemodialysed patients. 相似文献
39.
Hydrolysis of the epoxide groups of the copolymer glycidylmethacrylate - ethylenedi-methacrylate in variously concentrated sulphuric acid solutions was studied. An approximate activation energy of hydrolysis, 41 kJ mol?1, was determined from the temperature dependences. For the sake of comparison the effect of pH on the degree of hydrolysis over the whole range of pH values was examined, and the importance of the results with respect to other reactions of the copolymer used was discussed. 相似文献
40.
Polymeric composites were prepared by reticulate doping of poly(γ-methyl-L-glutamate) (PMLGA) and poly(γ-methyl-LD-glutamate) (PMLDGA, 1 : 1) having different conformation forms with 1,3-dimethylimidazolium-TCNQ complex salt. The heat induced α-helix to coil transition in PMLGA and α-helix to β-form and coil transition in PMLDGA were carried out in chlorobenzene and o-dichlorobenzene at temperatures between 70 and 150°C. The conductivity of polyglutamate composites thermally treated and prepared at 70°C is higher by approximately two orders of magnitude than that of thermally not treated films cast at ambient temperature. The conductivity of the most conductive reticulate-doped PMLGA film is higher by more than four orders of magnitude than that of the 1,3-dimethylimidazolium-TCNQ complex salt in pressed pellets. 相似文献