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91.
Improved contractility of obstructed bladders after Tadenan treatment is associated with reversal of altered myosin isoform expression 总被引:3,自引:0,他引:3
PURPOSE: Tadenan is a plant extract from Pygeum africanum used in the treatment of benign prostatic hyperplasia, to protect the bladder from contractile dysfunction induced by partial bladder outlet obstruction (BOO). The aim of the present study was to determine whether the Tadenan-induced return of detrusor contractility affects the expression of myosin isoforms, which differ at the C-terminal (SM1 and SM2) and the N-terminal regions (SM-A and SM-B). MATERIALS AND METHODS: Four groups of New Zealand White rabbits (3 to 5 kg., 4 to 6 rabbits per group) were either partially obstructed by ligation of the urethra (groups 1 and 2) or not obstructed (groups 3 and 4). After 2 weeks, rabbits from groups 2 and 4 received Tadenan in peanut oil (vehicle) orally at 100 mg. /kg./day for 3 weeks and rabbits in groups 1 and 3 received vehicle only. Rabbits were sacrificed and bladders were removed and weighed. Contractility studies were performed on isolated strips of detrusor and the remaining muscular layer from the bladder body was used to study the expression of myosin heavy chain (MHC) isoforms at mRNA (SM1, SM2, SM-A, and SM-B) and the protein (SM1 and SM2) levels by RT-PCR and SDS-PAGE analyses, respectively. RESULTS: Tadenan significantly reduced the effect of BOO on bladder mass. The diminished contractile response to field stimulation and carbachol secondary to urethral obstruction was significantly reversed by Tadenan treatment. The relative ratios for MHC isoforms were altered at the mRNA (SM2:SM1 and SM-A:SM-B) and protein (SM2:SM1) levels in obstruction. Upon treatment with Tadenan, the ratio of these isoforms returned to normal, as shown at the mRNA levels. In addition, the altered relative ratio of SM2:SM1 at the protein level also returned to nearly normal values after treatment. CONCLUSIONS: Improvement of obstruction-induced contractile dysfunction of the detrusor following treatment with Tadenan is associated with changes in the expression of myosin isoforms. The alteration in the expression of myosin isoforms associated with obstruction-induced hypertrophy is reversed close to normal in the detrusor smooth muscle from Tadenan-treated obstructed rabbits. 相似文献
92.
Emily S Patterson Emilie M Roth David D Woods Renée Chow José Orlando Gomes 《International journal for quality in health care》2004,16(2):125-132
OBJECTIVE: To describe strategies employed during handoffs in four settings with high consequences for failure. DESIGN: ANALYSIS: of observational data for evidence of use of 21 handoff strategies. SETTING: NASA Johnson Space Center in Texas, nuclear power generation plants in Canada, a railroad dispatch center in the United States, and an ambulance dispatch center in Toronto. MAIN MEASURE: Evidence of 21 handoff strategies from observations and interviews. RESULTS: Nineteen of 21 strategies were used in at least one domain, on at least an 'as needed' basis. CONCLUSIONS: An understanding of how handoffs are conducted in settings with high consequences for failure can jumpstart endeavors to modify handoffs to improve patient safety. 相似文献
93.
V M Gomes A O Carvalho M Da Cunha M N Keller C Bloch P Deolindo E W Alves 《Toxicon》2005,45(7):817-827
Different peptides have been isolated from a wide range of animal species. It is has become increasingly clear that due to the development of antibiotic-resistant microbes, antibacterial and antifungal peptides have attracted the attention in recent years, in order to find new therapeutic agents. In this work, a novel peptide with high inhibitory activity against fungi growth have been isolated from the venom of the Brazilian snake Bothrops jararaca. A Sephacryl S-100 gel filtration column was employed for further separation of proteins. The FV fraction with high antifungal activity was named Pep5Bj, pooled and submitted to reverse-phase chromatography in HPLC. The fraction containing the isolated peptide inhibited the growth of different phytopathogenic fungi (Fusarium oxysporum and Colletotrichum lindemuthianum) and yeast (Candida albicans and Saccharomyces cerevisiae). The peptide minimal inhibitory concentration is comparable to other known antifungal peptides, like insect defensins and cecropins, found in the last years in a large diversity of animals. We investigate F. oxysporum cells membrane permeabilization using SYTOX Green uptake, an organic compound that fluoresces upon interaction with nucleic acids after penetration in cell with compromised plasma membranes. When viewed under fluorescence optical microscopy, F. oxysporum cells exposed to Pep5Bj display strong SYTOX Green fluorescence in the cytosol, especially in the nuclei. The SYTOX Green data suggested that this effect is related to membrane permeabilization. The molecular masses of this peptide was obtained by MALDI-TOF spectrometry and corresponded to 1370Da. 相似文献
94.
Thomas J Cook Shanya Edwards Charlene Gyemah Manoj Shah Indu Shah Tiziana Fox 《Journal of the American Pharmacists Association》2004,44(5):583-586
OBJECTIVE: To determine the weight variation and calculated dosing variability of tablet fragments upon splitting unscored cyclobenzaprine hydrochloride 10 mg tablets using two common tablet splitting devices. DESIGN: Comparative pharmaceutics study. SETTING: Pharmacy school laboratory. PARTICIPANTS: Not applicable. INTERVENTIONS: Unscored cyclobenzaprine hydrochloride 10 mg tablets from one generic manufacturer were split with a tablet splitter or a kitchen knife by a licensed pharmacist and two doctor of pharmacy students (n = 15 tablets for each method per participant). MAIN OUTCOME MEASURES: Fragment weights (FWs) were compared with the theoretical weights (TWs), which were calculated as one half of the mean weight of the tablets used in each part of the experiment; means, relative standard deviations (RSDs), and percentages of TW were also calculated. RESULTS: The mean weight before splitting the 45 tablets with the tablet splitter was 136.6 +/- 2.1 mg (TW = 68.3 mg). The mean FW after splitting was 67.9 +/- 7.9 mg. The RSD of 11.6% corresponded to a range of 69.4% to 130.2% of the TW and an estimated drug content of the split fragments between 3.47 mg and 6.51 mg. The mean weight before splitting the 45 tablets cut with a kitchen knife was 136.6 +/- 2.0 mg (TW = 68.3 mg). The mean FW was 68.0 +/- 15.7 mg with a RSD of 23.2%, corresponding to a range of 49.9% to 149.5% of the TW and an estimated drug content of the split fragments between 2.49 mg and 7.48 CONCLUSION: Tablet fragments obtained after splitting this generic cyclobenzaprine 10 mg product varied considerably in weight and estimated drug content. Accordingly, splitting cyclobenzaprine 10 mg tablets to achieve 5 mg doses could result in unpredictable dosing and therapeutic response. 相似文献
95.
96.
Ana Teresa Martins Luis Faísca Francisco Esteves Cláudia Simo Mariline Gomes Justo Angélica Muresan Alexandra Reis 《中国神经再生研究》2012,7(2):101-108
Changes in social and emotional behaviour have been consistently observed in patients with traumatic brain injury. These changes are associated with emotion recognition deficits which represent one of the major barriers to a successful familiar and social reintegration. In the present study, 32 patients with traumatic brain injury, involving the frontal lobe, and 41 ageand education-matched healthy controls were analyzed. A Go/No-Go task was designed, where each participant had to recognize faces representing three social emotions (arrogance, guilt and jealousy). Results suggested that ability to recognize two social emotions (arrogance and jealousy) was significantly reduced in patients with traumatic brain injury, indicating frontal lesion can reduce emotion recognition ability. In addition, the analysis of the results for hemispheric lesion location (right, left or bilateral) suggested the bilateral lesion sub-group showed a lower accuracy on all social emotions. 相似文献
97.
Paula C. Eterovick Ryan Franckowiak Cibele Velloso-Rodrigues Jo?o Bruno G. C. Santos Rauber S. Garcia Josiane A. Gomes 《Conservation Genetics Resources》2012,4(2):483-485
We report 14 microsatellite loci for Bokermmanohyla saxicola, a frog species endemic of the Espinha?o mountain chain in southeastern Brazil. We used a sample of 53 individuals from a single locality to characterize these polymorphic loci. Number of alleles per locus ranged from 3 to 17, observed heterozygosity and expected heterozygosity ranged from 0.125 to 0.925 and from 0.137 to 0.907, respectively. These loci will be useful to understand population structure of this frog throughout its distribution, aiding to landscape conservation planning in the Espinha?o, considered a center of endemism and a priority area for conservation. 相似文献
98.
99.
100.
Rui Caetano-Oliveira Marcos António Gomes Ana Margarida Abrantes Edgar Tavares-Silva Marco Carvalho Oliveira Mafalda Laranjo Débora Basílio Queirós João Casalta-Lopes Salomé Pires Lina Carvalho Rosa Gouveia Paulo Rodrigues Santos Denise Gonçalves Priolli José Guilherme Tralhão Maria Filomena Botelho 《Pathophysiology》2018,25(2):89-99
Colorectal cancer (CRC) is the second most frequent and fatal cancer in Western countries. Understanding its biology with different incidence along the colon and rectum, genetic profile and how these factors contribute to local/distant progression, has been hampered by the lack of a suitable CRC model.We report a reproducible model, using human CRC cell lines (CL) (WiDr, LS1034, C2BBe1) injected (1?×?107 cells/animal) in RNU rats (n?=?55) which underwent cecostomy and descending colostomy with mucosal-cutaneous fistula of the sigmoid colon. CL were characterized by immunohistochemistry: CK20, CDX2, P53, vimentin, Ki67, CD44, CD133, E-cadherin, β-catenin and CEA; cancer stem cells-immune system interaction was studied and tumor progression was assessed with nuclear medicine imaging (99mTc-MIBI).Animals developed locally invasive tumors and with WiDr neural invasion was registered. Cancer stem cells were detected in WiDr (CD44 positive). All the cell lines stimulated the immune system, being WiDr the most aggressive. Imaging studies demonstrated tumor uptake.With this CRC model we can study the microenvironment role and tumor-stroma interactions. All CL developed primary disease, but only the WiDR established neural invasion which may represent a metastatic pathway. This model can help unveiling the underlying metastatic mechanisms, and ultimately test better therapeutic approaches for CRC. 相似文献