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71.
PURPOSE: The mouse eye is a widely used model for retinal disease and has potential to become a model for myopia. Studies of retinal disease will benefit from imaging the fundus in vivo. Experimental models of myopia often rely on manipulation of the visual experience. In both cases, knowledge of the optical quality of the eye, and in particular, the retinal image quality degradation imposed by the ocular aberrations is essential. In this study, we measured the ocular aberrations in the wild type mouse. METHODS: Twelve eyes from six four-week old black C57BL/6 wild type mice were studied. Measurements were done on awake animals, one being also measured under anesthesia for comparative purposes. Ocular aberrations were measured using a custom-built Hartmann-Shack system (using 680-nm illumination). Wave aberrations are reported up to fourth order Zernike polynomials. Spherical equivalent and astigmatism were obtained from the 2nd order Zernike terms. Modulation Transfer Functions (MTF) were estimated for the best focus, and through-focus, to estimate depth-of-focus. All reported data were for 1.5-mm pupils. RESULTS: Hartmann-Shack refractions were consistently hyperopic (10.12+/-1.41 D, mean and standard deviation) and astigmatism was present in many of the eyes (3.64+/-3.70 D, on average). Spherical aberration was positive in all eyes (0.15+/-0.07 microm) and coma terms RMS were significantly high compared to other Zernike terms (0.10+/-0.03 microm). MTFs estimated from wave aberrations show a modulation of 0.4 at 2c/deg, for best focus (and 0.15 without cancelling the measured defocus). For that spatial frequency, depth-of-focus estimated from through-focus modulation data using the Rayleigh criterion was 6D. Aberrations in the eye of one anesthetized mouse were higher than in the same eye of the awake animal. CONCLUSIONS: Hyperopic refractions in the mouse eye are consistent with previous retinoscopic data. The optics of the mouse eye is far from being diffraction-limited at 1.5-mm pupil, with significant amounts of spherical aberration and coma. However, estimates of MTFs from wave aberrations are higher than previously reported using a double-pass technique, resulting in smaller depth-of-field predictions. Despite the large degradation imposed by the aberrations these are lower than the amount of aberrations typically corrected by available correction techniques (i.e., adaptive optics). On the other hand, aberrations do not seem to be the limiting factor in the mouse spatial resolution. While the mouse optics are much more degraded than in other experimental models of myopia, its tolerance to large amounts of defocus does not seem to be determined entirely by the ocular aberrations. 相似文献
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73.
STUDY OBJECTIVE: To examine transvaginal hydrolaparoscopy (THL) practices in French tertiary care centers. DESIGN: Prospective longitudinal study (Canadian Task Force classification III). SETTING: University hospital in France. PARTICIPANTS: Gynecology and obstetrics departments of all 48 French teaching hospitals. INTERVENTIONS: Practice of THL using a 8-item questionnaire. MEASUREMENTS AND MAIN RESULTS: Main outcome measure was practice, indications, and complications of THL in French tertiary care centers. Between October 2005 and March 2006, the departments were sent an 8-item questionnaire on the use of diagnostic and operative THL. In all, 38 (79%) hospitals completed the questionnaire. THL was or is still used in 20 (53%) departments. The main reason given by the 18 departments that never used THL was that it was "less informative than laparoscopy." Only 8 (40%) of 20 departments with experience of THL continued to use the procedure routinely. The main reason given for abandoning THL was its limited operative potential. Among the 8 departments that continued to use THL, 6 used operative THL (mainly for ovarian drilling). Among the 30 departments that answered the item on the likely future place of THL, only 6 (20%) considered that THL would continue to be performed. CONCLUSION: Few French teaching hospitals routinely use THL. Further data on THL, and especially its cost effectiveness, are needed to clarify its place to evaluate female fertility. 相似文献
74.
de Paula Martins W Santana LF Nastri CO Ferriani FA de Sa MF Dos Reis RM 《European journal of obstetrics, gynecology, and reproductive biology》2007,133(2):203-207
OBJECTIVE: The objective was to compare agreement on the diagnosis of insulin resistance (IR) among insulin sensitivity indexes in both ovulatory women and those with polycystic ovary syndrome (PCOS). STUDY DESIGN: In an observational study, the 75-g oral glucose tolerance test was performed in 105 women with PCOS and 51 ovulatory women. The insulin sensitivity indexes used were insulin quantitative sensitivity check index (QUICKI), 1/homeostasis model assessment-insulin resistance (1/HOMA-IR), area under curve for insulin (AUC-I), and the Matsuda insulin sensitivity index (COMP). For the IR diagnosis we used cut-off values described in recent publications (insulin >12 microIU/ml, 1/HOMA-IR <0.47, QUICKI < or =0.333, AUC-I > or =7000 microIU/ml 120 min, and COMP <4.75. RESULTS: Excellent agreement was assessed among insulin, QUICKI, and 1/HOMA-IR. However, the rate of IR detected by these indexes in the PCOS group (44.8-51.4%) was lower than expected. New cut-offs were then determined based on COMP results. Using these values, 1/HOMA-IR and QUICKI showed excellent agreement (kappa=0.83) with COMP. CONCLUSION: The observed agreements among insulin, QUICKI and 1/HOMA-IR were higher than 93%. Therefore, clinicians may choose any of those obtaining similar results. For clinicians who prefer COMP, but are looking for a simpler test to detect IR in PCOS women, the use of QUICKI and 1/HOMA-IR with the new cut-offs seems reasonable. 相似文献
75.
Viloria T Garrido N Fernández JL Remohí J Pellicer A Meseguer M 《Fertility and sterility》2007,88(2):523-525
Toxic habits and their relationship with male factor infertility have been a matter of investigation in recent years, and smoking is one of the most common lifestyle toxic exposures to harmful substances. The analysis of sperm deoxyribonucleic acid fragmentation after capacitation detected a detrimental effect produced by tobacco, and this deleterious effect alters the sperm swim-up selection process in smokers, although the molecular and cellular basis of this phenomenon remain to be elucidated. 相似文献
76.
Rosa e Silva AC Rosa e Silva JC Reis RM Tone LG Silva de Sá MF Ferriani RA 《Journal of pediatric and adolescent gynecology》2007,20(2):89-91
STUDY OBJECTIVE: To determine the presence of impaired gonadal function in adolescent patients submitted to chemotherapy during childhood or during the pubertal period. DESIGN: A case series study of 28 patients aged 12 to 19 years with menarche at least 2 years before the study. SETTING: Tertiary care public hospital. PARTICIPANTS: Group I: 14 adolescents previously submitted to chemotherapy during the prepubertal or peripubertal period and with remission of oncologic disease for at least 2 years; Group II: 14 normal adolescents with no previous oncologic disease and with regular menstrual cycles. INTERVENTIONS AND MAIN OUTCOME MEASURES: Pubertal development, menstrual cycles and serum levels of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) were determined during the early follicular phase. RESULTS: There were no differences between the two groups in terms of age at appearance of secondary sexual characteristics or age at menarche. Menstrual irregularity was detected in 7 of the 14 patients in Group I, all 8 of whom presented oligomenorrhea. There were no differences in LH levels between the two groups (P = 0.55), although mean FSH levels were higher in Group I than in Group II (6.71 +/- 2.99 mIU/ml vs. 3.83 +/- 2.01 mIU/ml, P = 0.01). CONCLUSION: Although girls submitted to chemotherapy during the prepubertal or peripubertal period presented normal sexual development, the incidence of oligomenorrhea was higher than expected for their age, and FSH levels, although within normal limits, were higher than those seen in normally cycling girls. 相似文献
77.
dos Santos E dos Santos JE Ribeiro RP Rosa E Silva AC Moreira AC Silva de Sá MF 《Journal of pediatric and adolescent gynecology》2007,20(1):13-18
STUDY OBJECTIVE: To compare the cortisol levels and 24 hour salivary cortisol rhythm in patients with anorexia nervosa (AN) and normal controls. DESIGN: Prospective transversal controlled study. SETTING: Tertiary-referral University Hospital. PARTICIPANTS: Twenty-five patients aged 15 to 35 years, 13 of them with regular ovulatory cycles, and 12 with diagnosis of AN. INTERVENTIONS: Salivary and blood collection for cortisol 24-hour rhythm determination. MAIN OUTCOME: Salivary cortisol was determined at 9 am, 5 pm, and 11 pm. Seric follicle-stimulating hormone, luteinizing hormone (LH), prolactin, estradiol (E2), progesterone, dehydroepiandrosterone-S (DHEA-S), and cortisol were sampled together with the 9 am salivary sample. RESULTS: LH, E2, and DHEA-S levels were reduced in patients with AN. A correlation between salivary and serum cortisol levels was observed in the 9 am sample only in controls (r = 0.67, P = 0.01; AN: r = 0.48, P = 0.12). Cortisol rhythm was present in all control subjects, whereas it was absent in one third of AN patients. The area under the curve for the AN group with preserved rhythm was significantly higher than for the control group (Me = 6811 ng/dl/24h vs 3708 ng/dl/24 h; P = 0.034). CONCLUSION: Patients with AN have higher salivary cortisol levels when compared to normal women and some of them do not present circadian rhythm. 相似文献
78.
Gustavo Henrique Soares Takano Rivadvio Fernandes Amorim Vnia Moraes Ferreira Leonora Maciel de Souza Vianna Tercia Maria Mendes Lousa de Castro Marcos de Vasconcelos Carneiro Ísis de Araújo Oliveira Andrea Barretto Motoyama Fabiana Pirani Carneiro 《International journal of clinical and experimental pathology》2022,15(4):191
Introduction: In women, most malignant effusions are from breast and ovary primary carcinomas that have metastasized to body cavity fluids (pleural, peritoneal and pericardial). When carcinoma is diagnosed in effusions, it is not possible to identify its site of origin solely by cytology (morphology); therefore, immunocytochemistry is used as a complementary method. There are no immunocytochemical markers with 100% sensitivity and specificity for identifying carcinoma primary site. The markers most used are TTF-1 for the lung, GATA-3 for the breast, and PAX-8 for the ovary. The aim of this study was to evaluate the sensitivity and specificity of a panel including these markers for detecting the primary site of carcinoma in effusions. Methods: Samples of pleural, pericardial, and peritoneal effusions and peritoneal washings with carcinoma of known primary site from women (n = 60) and men (n = 18) were prepared by using the cell block method, and immunocytochemistry was performed to evaluate the expression of primary site markers (TTF-1, PAX-8, and GATA-3). Results: In women, the breast was the most frequent primary site of metastatic carcinoma to both pleural and pericardial cavities, followed by the lung, whereas the ovary was the most frequent primary site of carcinoma within peritoneal effusions and washings, followed by the gastrointestinal tract (stomach or intestine). The expected profiles for carcinomas of the most common primary sites were: breast (GATA-3 (+), PAX-8 (-), TTF-1 (-)), ovary (PAX-8 (+), GATA-3 (-), TTF-1 (-)), lung (TTF-1 (+), PAX-8 (-) GATA-3 (-)) and gastrointestinal tract (PAX-8 (-), GATA-3 (-), TTF-1 (-)). These were observed in 88.23% (45/51) of women’s samples with carcinoma from these primary sites. By using TTF-1 as the sole primary site marker, 6.25% of carcinomas of primary site other than the lung would have been misdiagnosed. Conclusion: An initial panel of markers including GATA-3, PAX-8, and TTF-1 allows, with high sensitivity and specificity, the identification or exclusion of frequent primary sites of carcinoma in effusions from women. Our results highlight the importance of using a panel of markers to avoid misidentification of the primary site of tumor. 相似文献
79.
80.
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