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81.
Sisci D Morelli C Garofalo C Romeo F Morabito L Casaburi F Middea E Cascio S Brunelli E Andò S Surmacz E 《Journal of clinical pathology》2007,60(6):633-641
BACKGROUND: Insulin receptor substrate 1 (IRS-1), a cytoplasmic protein transmitting signals from the insulin and insulin-like growth factor 1 receptors, has been implicated in breast cancer. Previously, it was reported that IRS-1 can be translocated to the nucleus and modulate oestrogen receptor alpha (ERalpha) activity in vitro. However, the expression of nuclear IRS-1 in breast cancer biopsy specimens has never been examined. AIMS: To assess whether nuclear IRS-1 is present in breast cancer and non-cancer mammary epithelium, and whether it correlates with other markers, especially ERalpha. Parallel studies were carried out for the expression of cytoplasmatic IRS-1. METHODS: IRS-1 and ERalpha expression was assessed by immunohistochemical analysis. Data were evaluated using Pearson's correlation, linear regression and receiver operating characteristic analysis. RESULTS: Median nuclear IRS-1 expression was found to be low in normal mammary epithelial cells (1.6%) and high in benign tumours (20.5%), ductal grade 2 carcinoma (11.0%) and lobular carcinoma (approximately 30%). Median ERalpha expression in normal epithelium, benign tumours, ductal cancer grade 2 and 3, and lobular cancer grade 2 and 3 were 10.5, 20.5, 65.0, 0.0, 80 and 15%, respectively. Nuclear IRS-1 and ERalpha positively correlated in ductal cancer (p<0.001) and benign tumours (p<0.01), but were not associated in lobular cancer and normal mammary epithelium. In ductal carcinoma, both nuclear IRS-1 and ERalpha negatively correlated with tumour grade, size, mitotic index and lymph node involvement. Cytoplasmic IRS-1 was expressed in all specimens and positively correlated with ERalpha in ductal cancer. CONCLUSIONS: A positive association between nuclear IRS-1 and ERalpha is a characteristic for ductal breast cancer and marks a more differentiated, non-metastatic phenotype. 相似文献
82.
Aquila S Middea E Catalano S Marsico S Lanzino M Casaburi I Barone I Bruno R Zupo S Andò S 《Human reproduction (Oxford, England)》2007,22(10):2594-2605
BACKGROUND: Results from mice lacking the androgen receptor (AR) showed that it is critical for the proper development and function of the testes. The aim of this study was to investigate whether a functional AR is present in human sperm. METHODS: The expression of AR and its effects on sperm were evaluated by RT-PCR, Western Blot, Immunocytochemistry, PI3Kinase and DNA laddering assays. RESULTS: We showed in human sperm that AR is located at the head region. Dihydrotestosterone (DHT), in a dose-dependent manner, leads to the rapid phosphorylation of the AR on tyrosine, serine and threonine residues and this effect was reduced by the AR antagonist hydroxyflutamide (OH-Flut). The effects of AR were evaluated on the phosphoinositide-3 kinase/protein kinase B (PI3K/AKT) pathway. Specifically, 0.1 and 1 nM DHT stimulated PI3K activity, whereas 10 nM DHT decreased PI3K activity and levels of p-AKT S473 and p-AKT T308, p-BCL2, and enhanced phosphatase and tensin homologue (PTEN) phosphorylation. In addition, 10 nM DHT was able to induce the cleavage of caspases 8, 9 and 3 and cause DNA laddering, and these effects were reversed either by casodex or OHFlut. By using wortmannin, a specific PI3K inhibitor, the cleavage of caspase 3 was reproduced, confirming that in sperm the PI3K/AKT pathway is involved in caspase activation. CONCLUSIONS: Human sperm express a functional AR that have the ability to modulate the PI3K/AKT pathway, on the basis of androgen concentration. 相似文献
83.
Optical mapping of excitation dynamically tracks electrical waves travelling through cardiac or brain tissue by the use of fluorescent dyes. There are several characteristics that set optical mapping apart from other imaging modalities: dynamically changing signals requiring short exposure times, dim fluorescence demanding sensitive sensors and wide fields of view (low magnification) resulting in poor optical performance. These conditions necessitate the use of optics with good light gathering ability, i.e. lenses having high numerical aperture. Previous optical mapping studies often used sensor resolution to estimate the minimum spatial feature resolvable, assuming perfect optics and infinite contrast. We examine here the influence of finite contrast and real optics on the effective spatial resolution in optical mapping under broad-field illumination for both lateral (in-plane) resolution and axial (depth) resolution of collected fluorescence signals. 相似文献
84.
Emilia Klimaszewska Anna Małysa Małgorzata Zięba Joanna Lipińska 《Pharmaceutical development and technology》2018,23(8):780-786
The study investigated the effect of chamomile extract obtained in supercritical carbon dioxide conditions on the basic properties of pharmaceutical ointments. A total of five formulations were designed and prepared, differing in the weight ratio of sunflower oil to chamomile extract (5:0, 3.5:1.5, 2.5:2.5, 1.5:3.5 and 0:5). An increase in the concentration of chamomile extract was found to be accompanied by a decrease in hardness, adhesive power and flow limit. Based on viscosity measurements it was shown that ointments containing the hydrophobic plant extract under study were prone to larger drops in viscosity under the effect of the set shear rate. It was determined that from the viewpoint of ointment spreadability and application to the skin, the optimum concentration of chamomile extract for the studied formulations should be within the range of 1.5–2.5%. Furthermore, the addition of chamomile extract to ointments was found to give samples a yellow-green color. Green was observed to be the dominant color, and its saturation and shade varied for different formulations. 相似文献
85.
Rodriguez-Tudela JL Gomez-Lopez A Alastruey-Izquierdo A Mellado E Bernal-Martinez L Cuenca-Estrella M 《Diagnostic microbiology and infectious disease》2007,58(4):435-440
The sequence polymorphisms of intergenic transcribed spacer and the antifungal susceptibility profile of 18 Trichosporon asahii isolates from Spain, Argentina, and Brazil together with 43 intergenic transcribed spacer 1 sequences deposited in the GenBank were analyzed. Six genotypes were detected instead of 5 genotypes described previously. Genotype 1 was the most common found comprising 57.3% of all strains, followed by genotype 3 (14.7%) and genotype 5 (13.1%). Spanish strains had members in all genotypes except 2, whereas South American isolates were grouped with genotypes 1, 3, and 6. Our results indicate that all genotypes are present in at least 2 countries suggesting a worldwide distribution. On the other hand, genotype 6 was not previously described but was only composed of 2 South American strains isolated from a subcutaneous abscess and skin. All isolates showed amphotericin B MICs>or=2 mg/L supporting the in vitro resistance of this species to this antifungal. Three isolates from South America showed high MICs to all antifungals analyzed. The true epidemiologic usefulness of classifying T. asahii in genotypes should be ascertaining analyzing a high number of isolates from many countries. 相似文献
86.
Diego Emilia J. Rosenberger Laura H. Deng Xiaoyan McGuire Kandace P. 《Annals of surgical oncology》2022,29(10):6162-6162
Annals of Surgical Oncology - 相似文献
87.
88.
Jamie E. Anderson Anne Erickson Carlos Funzamo Peter Bendix Americo Assane John Rose Fernando Vaz Emilia Virginia Noormahomed Stephen W. Bickler 《World journal of surgery》2014,38(4):823-829
Background
The World Health Organization has identified the primary referral hospital as its priority site for improving surgical care in low- and middle-income countries. Little is known about the relative burden surgical patients place on health care facilities at this level. This research estimates the fraction of admissions due to surgical conditions at three hospitals in rural Mozambique.Methods
Prospective data were collected on all inpatients at three primary referral hospitals in Mozambique during a 12-day period. We compared the number of surgical patients and their length of stay (LOS) to the patients admitted to the medicine, pediatric, and maternity wards. These findings were validated using retrospective data collected from one hospital from January to May 2012.Results
Patients with surgical conditions (i.e., patients admitted to the surgical or maternity ward) accounted for 57.5 % of admissions and 48.0 % of patient-days. The majority of patients were admitted to the maternity ward (32.3 %). The other admissions were evenly distributed to the pediatric (22.5 %), medical (20.0 %), and surgical (25.2 %) wards. Compared to patients from the three other wards, surgical patients had longer average LOS (8.7 vs. 1.9–7.7 days) and a higher number of total patient-days (891 vs. 252–703 days). The most prevalent procedures were cesarean section (33.3 %) and laceration repair/wound care (11.8 %).Conclusions
Surgical conditions are the most common reason for admissions at three primary referral hospitals in rural Mozambique. These data suggest that surgical care is a major component of health care delivered at primary referral hospitals in Mozambique and likely other sub-Saharan African countries. 相似文献89.
Marco Monticone Emilia Ambrosini Barbara Rocca Silvia Magni Flavia Brivio Simona Ferrante 《European spine journal》2014,23(10):2105-2113