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101.
Although much is known about the pathogenesis of crotoxin-induced muscle damage, the initial site and action of the toxin is still not clear. In this study we used an electrochromic fluorescent dye, Di-4-ANEPPS, to measure the changes in membrane potential of isolated murine omohyoid muscle to determine if depolarization could be one of the initial effects of crotoxin. Omohyoid isolates were pre-loaded with 1 microM Di-4-ANEPPS, exposed to various crotoxin treatments, and the change in fluorescence was recorded using either a dual-wavelength spectrofluorometer or digital imaging. Spectrofluorometry indicated that crotoxin depolarized isolated omohyoid muscles within 4 min as indicated by an increase in fluorescence to 122% of control values. Crotoxin also induced depolarization of extensor digitorum longus and soleus muscles as indicated by an increase in fluorescence of 140 and 110% of the control, respectively. Fluorescent images obtained from omohyoid muscle preparations exposed to crotoxin and Di-4-ANEPPS revealed localized areas of increased fluorescence, muscle contractions, derangement of myofibrils, and differing sensitivity to crotoxin of different muscle cells. Light microscopy results confirmed this variable disruption of muscle cell integrity and differing sensitivity to crotoxin. An increase in creatine kinase release rates confirmed damage to the plasma membrane. We conclude that plasma membrane depolarization is most likely the earliest indicator of cell damage from crotoxin and is quickly followed by hypercontraction of myofilaments, disruption of the plasma membrane, release of creatine kinase and necrosis. 相似文献
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Background
Ischemic heart disease (IHD) is one of the most important causes of mortality and morbidity in the Western world. There is a relationship between aging of the lens of the human eye and cardiovascular disease. The present study was conducted to examine if the risk of ischemic heart disease could be estimated by fluorophotometric assessment of lens aging. 相似文献105.
106.
Heavey EJ Moysich KB Hyland A Druschel CM Sill MW 《Journal of Midwifery & Women's Health》2008,53(4):338-344
Our objective was to examine the relationship between pregnancy desire among female adolescents and their perception of desire for pregnancy in their male partners. This is an observational cross-sectional study which examined 92 surveys administered to adolescent women between the ages of 14 to 19 years at two obstetrical care services serving a population from limited socioeconomic backgrounds. Participants were all pregnant or awaiting pregnancy test results. Participants were asked about their levels of pregnancy happiness and desire and their partners' levels of pregnancy happiness and desire. Spearman's correlation coefficient was calculated and discordant pairs were examined with McNemar's test. Logistic regression was utilized to examine the relationship between male and female pregnancy happiness and desire. We found that there was a significant correlation between the adolescents' feelings about pregnancy and their perceptions of their male partners' feelings about pregnancy (0.326; P = .004). McNemar's test indicated that male partners were significantly more likely to be reported to feel positively about the pregnancy than female partners (P = .017). Female adolescents who reported male partners who felt positively about the pregnancy were four times as likely to report having desired their pregnancy now or sooner (odds ratio [OR] = 4.35). We conclude that male partners may impact adolescent pregnancy desire. Further prospective studies are needed and male-focused adolescent pregnancy interventions should be developed. 相似文献
107.
Barbat A Gloaguen V Moine C Sainte-Catherine O Kraemer M Rogniaux H Ropartz D Krausz P 《Journal of natural products》2008,71(8):1404-1409
Xylans were purified from delignified holocellulose alkaline extracts of Castanea sativa (Spanish chestnut) and Argania spinosa (Argan tree) and their structures analyzed by means of GC of their per-trimethylsilylated methylglycoside derivatives and (1)H NMR spectroscopy. The structures deduced were characteristic of a 4-O-methylglucuronoxylan (MGX) and a homoxylan (HX), respectively, with degrees of polymerization ranging from 182 to 360. In the case of MGX, the regular or random distribution of 4-O-methylglucuronic acid along the xylosyl backbone--determined by MALDI mass spectrometry after autohydrolysis of the polysaccharide--varied and depended both on the botanical source from which they were extracted and on the xylan extraction procedure. The MGX also inhibited in different ways the proliferation as well as the migration and invasion capability of A431 human epidermoid carcinoma cells. These biological properties could be correlated with structural features including values of the degree of polymerization, 4-O-MeGlcA to xylose ratios, and distribution of 4-O-MeGlcA along the xylosyl backbone, giving evidence of a defined structure-activity relationship. 相似文献
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109.
Crotzer DR Sun CC Coleman RL Wolf JK Levenback CF Gershenson DM 《Gynecologic oncology》2007,105(2):404-408
OBJECTIVE: Clear cell carcinoma of the ovary is an aggressive tumor characterized by relative chemoresistance and a poor prognosis. The purpose of this study was to review our experience with recurrent clear cell carcinoma of the ovary to evaluate its responsiveness to systemic cytotoxic and hormonal agents. METHODS: All patients diagnosed with clear cell carcinoma of the ovary seen at our institution between 1990 and 2002 were identified and their medical records reviewed. Eligibility criteria were: 1) primary diagnosis of clear cell carcinoma of the ovary, 2) measurable recurrent disease, 3) treatment of recurrent disease with 1 or more systemic regimens, and 4) adequate clinical information. End points were clinical response, progression-free survival, and overall survival. RESULTS: Fifty-one patients treated for recurrent clear cell carcinoma were identified. The patients received a total of 105 regimens (344 cycles of therapy). Among patients with platinum-sensitive disease (n=22 regimens), 2 patients (9%) had partial responses to retreatment with carboplatin plus paclitaxel, and 4 (18%) had stable disease. Among patients with platinum-resistant disease (n=83 regimens), only 1 patient (1%) had a partial response - to gemcitabine - and 1 patient had stable disease in response to 2 different regimens-paclitaxel and gemcitabine. The median progression-free survival was 8 months, and the median overall survival was 18 months. CONCLUSION: Our findings suggest that recurrent clear cell carcinoma of the ovary is particularly chemoresistant. A continued search for more active, targeted agents is warranted. 相似文献
110.
Arianne C Lim Kitty WM Bloemenkamp Kees Boer Johannes J Duvekot Jan Jaap HM Erwich Tom HM Hasaart Pieter Hummel Ben WJ Mol Jos PM Offermans Charlotte M van Oirschot Job G Santema Hubertina CJ Scheepers Willem A Schöls Frank PHA Vandenbussche Maurice GAJ Wouters Hein W Bruinse 《BMC pregnancy and childbirth》2007,7(1):1-6