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991.
Combined effects of inhaled nitric oxide and a recruitment maneuver in patients with acute respiratory distress syndrome 总被引:1,自引:0,他引:1
Nitric oxide (NO) inhalation therapy has been employed in the management of acute respiratory distress syndrome (ARDS), in order to improve oxygenation. Several factors have been implicated as being responsible for the action of inhaled NO. Alveolar recruitment methods, such as prone positioning and a sufficient positive end expiratory pressure (PEEP), have been identified as having a positive impact on the NO response. A Recruitment maneuver (RM) was introduced for the treatment of ARDS, along with a lung protective strategy. Here, we hypothesized that a RM may further augment the oxygenation of patients treated with NO inhalation. Therefore, the effects of the inhalation of NO, either in combination with a RM, or separately, were evaluated on patients with ARDS for their enhancing action. 23 patients with ARDS were enrolled, and divided into three groups. The patients in group 1 (n=11) were treated with 5 ppm NO via inhalation, followed by a RM, applying a sustained inflation pressure of 30 - 35 cmH2O for 30 seconds. Group 2 (n=6) received a RM alone, while group 3 (n=3) was treated with NO inhalation alone. The oxygenation and hemodynamic parameters were obtained prior to, and 2, 12, and 24 h after, the respective treatment procedures. For group 1, the PaO2/FiO2 increased from its initial value of 171.8 +/- 67.8 to 203.2 +/- 90.0 2 h after NO inhalation. Further improvement was noted with the continual application of the RM reaching, 215.5 +/- 74.6 (p=0.05) and 254.2 +/- 109.5 (p < 0.05), after 12 and 24 h, respectively. Initially 7 of the subjects did not respond to NO inhalation, but 3 of these non-responders changed into responders 12 h after the RM. The changes in the PaO2/FiO2 from baseline at each time period were greater in group 1 than in the other groups, but with no statistical significance. The hemodynamics of the patients was not significantly altered during the entire study period. We conclude that the combined application of NO inhalation and a RM could be beneficial and safe for patients with ARDS, showing an enhancing effect in improvement of oxygenation. 相似文献
992.
Kim HS Lee SH Lee JW Soung YH Lee JH Park JY Cho YG Kim CJ Kim SY Lee YS Park WS Kim SH Lee JY Yoo NJ 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2003,111(4):490-491
Among the systems triggering apoptosis, the Fas-Fas ligand (FasL) system is recognized as a major pathway for the induction of apoptosis in cells and tissues. Ligation of Fas by either an agonistic antibody or FasL transmits a 'death signal' to the target cell, potentially triggering apoptosis. Alterations of genes along the Fas-mediated apoptosis pathway have been reported in many human cancers. However, there have been no data regarding FasL gene mutations in human cancers. We hypothesized that FasL gene mutation might be involved in the development of non-Hodgkin lymphoma (NHL). In this study, we analyzed the entire coding region of the FasL gene for the detection of somatic mutations in a series of 111 NHLs and found that one tumor had a FasL gene mutation in the cytoplasmic domain. To evaluate the functional alterations of the mutant in apoptosis, we overexpressed the mutant in 293T cells, but couldn't find any significant loss of cell death compared to the wild-type FasL. Together, these data suggest that FasL is occasionally mutated in human NHL and that FasL mutations appear to play no role in the pathogenesis of the vast majority of NHLs. 相似文献
993.
Mutational analysis of Noxa gene in human cancers 总被引:4,自引:0,他引:4
Lee SH Soung YH Lee JW Kim HS Lee JH Kim HS Lee JH Park JY Cho YG Kim CJ Kim SY Park WS Kim SH Lee JY Yoo NJ 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2003,111(6):599-604
There has been mounting evidence that dysregulation of apoptosis is involved in the mechanisms of cancer development and somatic mutations of apoptosis-related genes have been reported in human cancers. Noxa, a Bcl-2 homology 3 (BH3)-only member of the Bcl-2 family, is known to interact with anti-apoptotic Bcl-2 family members and induces apoptosis. The aim of this study was to explore the possibility that the Noxa gene is mutated in human cancers. We have analyzed the entire coding region and all splice sites of the Noxa gene for the detection of somatic mutations in a series of human cancers, including carcinomas from stomach, colon, liver, urinary bladder and lung by polymerase chain reaction (PCR), single strand conformation polymorphism (SSCP), and DNA sequencing. We found one somatic mutation of the Noxa gene in a transitional cell carcinoma (TCC) of the urinary bladder. To evaluate the functional alterations of the mutant in apoptosis, we overexpressed the mutant and wild-type Noxa in 293T and HeLa cells, but could not find any significant difference in cell death between the wild-type and mutant Noxa. These data suggest that Noxa is rarely mutated in human carcinomas and that the contribution of Noxa gene mutation in the pathogenesis of human cancer might not be related to cell death mechanisms. 相似文献
994.
Jae Y. Lee Chris A. Bashur Aaron S. Goldstein Christine E. Schmidt 《Biomaterials》2009,30(26):4325-4335
Electrospinning is a promising approach to create nanofiber structures that are capable of supporting adhesion and guiding extension of neurons for nerve regeneration. Concurrently, electrical stimulation of neurons in the absence of topographical features also has been shown to guide axonal extension. Therefore, the goal of this study was to form electrically conductive nanofiber structures and to examine the combined effect of nanofiber structures and electrical stimulation. Conductive meshes were produced by growing polypyrrole (PPy) on random and aligned electrospun poly(lactic-co-glycolic acid) (PLGA) nanofibers, as confirmed by scanning electron micrographs and X-ray photon spectroscopy. PPy–PLGA electrospun meshes supported the growth and differentiation of rat pheochromocytoma 12 (PC12) cells and hippocampal neurons comparable to non-coated PLGA control meshes, suggesting that PPy–PLGA may be suitable as conductive nanofibers for neuronal tissue scaffolds. Electrical stimulation studies showed that PC12 cells, stimulated with a potential of 10 mV/cm on PPy–PLGA scaffolds, exhibited 40–50% longer neurites and 40–90% more neurite formation compared to unstimulated cells on the same scaffolds. In addition, stimulation of the cells on aligned PPy–PLGA fibers resulted in longer neurites and more neurite-bearing cells than stimulation on random PPy–PLGA fibers, suggesting a combined effect of electrical stimulation and topographical guidance and the potential use of these scaffolds for neural tissue applications. 相似文献
995.
Background
Chronic inflammation is a characteristic of Alzheimer's disease (AD). An interaction associated with the risk of AD has been reported between polymorphisms in the regulatory regions of the genes for the pro-inflammatory cytokine, interleukin-6 (IL-6, gene: IL6), and the anti-inflammatory cytokine, interleukin-10 (IL-10, gene: IL10).Methods
We examined this interaction in the Epistasis Project, a collaboration of 7 AD research groups, contributing DNA samples from 1,757 cases of AD and 6,295 controls.Results
We replicated the interaction. For IL6 rs2069837 AA × IL10 rs1800871 CC, the synergy factor (SF) was 1.63 (95% confidence interval: 1.10–2.41, p = 0.01), controlling for centre, age, gender and apolipoprotein E ε4 (APOEε4) genotype. Our results are consistent between North Europe (SF = 1.7, p = 0.03) and North Spain (SF = 2.0, p = 0.09). Further replication may require a meta-analysis. However, association due to linkage disequilibrium with other polymorphisms in the regulatory regions of these genes cannot be excluded.Conclusion
We suggest that dysregulation of both IL-6 and IL-10 in some elderly people, due in part to genetic variations in the two genes, contributes to the development of AD. Thus, inflammation facilitates the onset of sporadic AD. 相似文献996.
Jo‐Heon Kim M.D. Ga‐Eon Kim M.D. Yoo Duk Choi M.D. Ji Shin Lee M.D. Jae Hyuk Lee M.D. Jong‐Hee Nam M.D. Chan Choi M.D. 《Diagnostic cytopathology》2009,37(4):258-261
The aim of our study was to determine the value of a panel that consisted of one epithelial marker (MOC‐31) and two mesothelial markers (D2‐40 and calretinin) for distinguishing between reactive mesothelial cells (RMCs) and adenocarcinomas (ACs) in effusion fluids. A total of 118 cell block specimens from pleural and peritoneal effusions, including 88 ACs and 30 benign effusions with RMCs were stained with antibodies against MOC‐31, D2‐40, and calretinin. MOC‐31 membranous activity was observed in all samples from ACs, regardless of the primary tumor site. All benign effusion samples with RMCs were negative for MOC‐31. All benign effusion samples with RMCs exhibited membranous staining for D2‐40, and one AC case had focal reactivity for D2‐40. Almost all benign effusions reacted positively with calretinin. Staining was noted in both the cytoplasm and the nucleus in the majority of cases. Scattered tumor cells had weak calretinin positivity in two AC cases. Background RMCs in AC effusions were consistently positive for D2‐40 and calretinin. In general, D2‐40 identified more RMCs than calretinin. The staining combination of positive for MOC‐31 and negative for D2‐40 or calretinin were 100% specific and 99% sensitive for ACs. Our data suggest that immunohistochemical studies performed on cell blocks with MOC‐31, D2‐40, and calretinin were useful in the differentiation between ACs and RMCs. D2‐40 was a more sensitive marker for RMCs than calretinin. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc. 相似文献
997.
Serum high mobility group box-1 (HMGB1) is closely associated with the clinical and pathologic features of gastric cancer 总被引:1,自引:0,他引:1
Hye Won Chung Sang-Guk Lee Heejung Kim Duck Jin Hong Jae Bock Chung David Stroncek Jong-Baeck Lim 《Journal of translational medicine》2009,7(1):38
Background
High mobility group box-1 (HMGB1) is a newly recognized factor regulating cancer cell tumorigenesis, expansion and invasion. We investigated the correlation between the serum HMGB1 levels and the clinical and pathologic features of gastric cancer and evaluated the validity of HMGB1 as a potential biomarker for the early diagnosis of gastric cancer. 相似文献998.
Choong Keun Cha Hyeok Choon Kwon Jae Youn Cheong Sung Won Cho MD Sun Pyo Hong Soo‐Ok Kim Wang Don Yoo 《Journal of medical virology》2009,81(3):417-424
Adefovir has a potent antiviral activity as a rescue treatment against lamivudine‐resistant strains. The aim of this study was to assess the patterns of lamivudine‐resistant mutations and their influence on the virologic response to adefovir rescue therapy in patients with lamivudine‐resistant chronic hepatitis B. Sixty‐seven patients with lamivudine‐resistant chronic hepatitis B were treated with adefovir monotherapy. Baseline blood samples were analyzed for lamivudine‐resistant mutations via restriction fragment mass polymorphism. Virologic responses, ALT normalization and loss of HBeAg were assessed. Serum HBV DNA levels were measured using real‐time PCR at baseline and 24 weeks of adefovir therapy. Of the 67 patients with chronic hepatitis B, 65 patients (97%) had lamivudine‐resistant mutations in the YMDD motif [27 (41%) rtM204I, 22 (34%) rtM204V, and 16 (25%) rtM204I/V]. In addition to the YMDD mutations, the rtL180M, rtL80I, and rtV173L mutations were also present in 78%, 43%, and 11% of patients, respectively. The rtM204V mutation always accompanied rtL180M, and rtL80I was always observed in conjunction with rtM204I. Decrease in mean serum HBV did not differ between patients carrying the rtM204I versus rtM204V mutant at week 24 (?3.3 vs. ?3.3 log10 copies/ml, respectively; P = 0.303). The presence of the rtL180M, rtL80I, and rtV173L did not significantly affect viral load reduction during adefovir administration. These results demonstrate that the rtL80I mutant is co‐selected with rtM204I as a compensatory mutation in the same manner as rtL180M with rtM204V, and that adefovir shows similar antiviral efficacy against all of the evaluated patterns of lamivudine‐resistant HBV mutations. J. Med. Virol. 81:417–424, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
999.
Kyung Min Park Sang Young Lee Yoon Ki Joung Jae Sik Na Myung Chul Lee Ki Dong Park 《Acta biomaterialia》2009,5(6):1956-1965
Injectable hydrogels have been studied for potential applications for articular cartilage regeneration. In this study, a thermosensitive chitosan–Pluronic (CP) hydrogel was designed as an injectable cell delivery carrier for cartilage regeneration. The CP conjugate was synthesized by grafting Pluronic onto chitosan using EDC/NHS chemistry. The sol–gel phase transition and mechanical properties of the CP hydrogel were examined by rheological experiments. The CP solution underwent a sol–gel transition around 25 °C at which the storage modulus (G′) approaches 104 Pa, highlighting the potential of this material as an injectable scaffold for cartilage regeneration. The CP hydrogel was formed rapidly by increasing the temperature. The morphology of the dried CP hydrogel was observed by scanning electron microscopy. In vitro cell culture was performed using bovine chondrocytes. The proliferation of bovine chondrocytes and the amount of synthesized glycosaminoglycan increased for 28 days. These results suggested that the CP hydrogel has potential as an injectable cell delivery carrier for cartilage regeneration and could serve as a new biomaterial for tissue engineering. 相似文献
1000.
Hwal Rim Jeong Hye Jin Lee Yeong Suk Shim Min Jae Kang 《Gynecological endocrinology》2019,35(8):732-736
This study evaluated the serum level of MKRN3 and investigated its diagnostic usefulness in girls with central precocious puberty (CPP). In total, 41 girls with CPP and 35 age-matched normal control girls were enrolled. Serum values of MKRN3 were measured in both groups. Gonadotropin and estradiol concentrations were evaluated after 6 and 12?months of GnRH agonist (GnRHa) treatment in CPP patients. The MKRN3 concentrations were much lower in the patient group than in the control group (p?=?.005). Over 1 year of GnRHa treatment in patients, the gonadotropin concentrations were significantly decreased (p?<?.05), while the MKRN3 concentrations were unchanged (p?>?.05). MKRN3 levels were inversely correlated to standard deviation (SD) in height (r?=??0.46, p?=?.000), SD in weight (r?=??0.32, p?=?.005), Tanner stage (r?=??0.41, p?=?.000), and bone age (r?=??0.46, p?=?.000). Based on ROC analysis, the area under curve was 0.758 for MKRN3, with 82.9% sensitivity and 68.5% specificity. The measurement of serum MKRN3 level may provide some help for CPP prediction, but relatively various values need further validation 相似文献