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61.
It is well established that some agents such as aminoglycosides generate free oxygen radicals, leading to an increased oxireductase production, which in turn increases tissue toxicity. The aim of this study is to test whether melatonin, the chief secretory product of the pineal gland and a highly effective antioxidant and free radical scavenger, reduces the nephrotoxicity caused by amikacin (AK). Herein, we investigated the physiologic and pharmacological role of melatonin in influencing AK-induced nephrotoxicity. For this, pinealectomized (Px) and sham operated (non-Px) rats were used. Both AK and melatonin were administered to all groups. We investigated the effects of melatonin on AK-induced changes in levels of malondialdehyde (MDA), a lipid peroxidation product, glutathione (GSH), an antioxidant whose levels are influenced by oxidative stress, and blood urea nitrogen (BUN) and serum creatine (Cr) levels. Morphologic changes in the kidney were also examined by using light microscopy. MDA levels were found to be higher in Px than in non-Px AK-treated animals. Melatonin administration to Px rats reduced MDA levels. In relative to non-Px rats, Px animals treated with AK had significantly lower GSH concentrations while melatonin administration elevated GSH levels in the kidney; however, this stimulatory effect of melatonin was not observed in non-Px AK-treated rats. Treatment with AK alone resulted in significantly higher plasma Cr and BUN levels. Repeated administration of melatonin prevented the AK-induced elevation of plasma Cr and BUN levels. Morphologic damage to renal tubules as a result of AK was more severe in the renal cortex than in the medulla. The damage to the kidney induced by AK was reversed by melatonin in the Px rats. In conclusion, these results show that physiologic melatonin concentrations are important in reducing AK-induced renal damage, while pharmacologic concentrations of melatonin did not add to the beneficial effect.  相似文献   
62.
Cisplatin [cis-diaminedichloroplatinum(II), CDDP] is a widely used antineoplastic drug. However, it has major side-effects such as acute tubular necrosis (ATN). There are a number of studies concerning the role of reactive oxygen radical species in the pathophysiology of CDDP-dependent ATN. Several antioxidant agents have been reported to prevent this side-effect but there is no study regarding the protective action of either physiological or pharmacological concentrations of melatonin. Melatonin, the chief secretory product of the pineal gland, is a direct free radical scavenger and indirect antioxidant. We investigated the effects of melatonin on CDDP-induced changes of renal malondialdehyde (MDA), a lipid peroxidation product, and blood urea nitrogen (BUN) and serum creatine (Cr). The morphological changes in kidney were also examined using light microscopy. The rats were divided into two groups: pinealectomized (Px) and sham-operated (non-Px). Both CDDP and melatonin were administered to all groups. MDA levels were found to be higher in Px than non-Px animals. CDDP administration to Px or non-Px rats increased renal MDA levels and melatonin administration either before or after CDDP injection caused significant decreases in MDA in kidney compared with those in rats treated with CDDP alone. Serum levels of BUN and Cr did not change as a result of any treatment. Morphological tubule damage because of CDDP was more severe in the renal cortex than in the medulla. The damage to the kidney induced by CDDP was reversed by melatonin. The results show that pharmacological and physiological concentrations of melatonin reduce CDDP-induced renal injury.  相似文献   
63.
When anthropometric methods were introduced into clinical practice to quantify changes in the craniofacial framework, features distinguishing various races/ethnic groups were discovered. To treat congenital or post-traumatic facial disfigurements in members of these groups successfully, surgeons require access to craniofacial databases based on accurate anthropometric measurements. Normative data of facial measurements are indispensable to precise determination of the degree of deviations from the normal. The set of anthropometric measurements of the face in the population studied was gathered by an international team of scientists. Investigators in the country of the given ethnic group, experienced and/or specially trained in anthropometric methods, carried out the measurements. The normal range in each resultant database was then established, providing valuable information about major facial characteristics. Comparison of the ethnic groups' databases with the established norms of the North America whites (NAW) offered the most suitable way to select a method for successful treatment. The study group consisted of 1470 healthy subjects (18 to 30 years), 750 males and 720 females. The largest group (780 subjects, 53.1%) came from Europe, all of them Caucasians. Three were drawn from the Middle-East (180 subjects, 12.2%), five from Asia (300 subjects, 20.4%) and four from peoples of African origin (210 subjects, 14.3%). Their morphological characteristics were determined by 14 anthropometric measurements, 10 of them used already by classic facial artists, Leonardo da Vinci and Albrecht Dürer, complemented by four measurements from the nasal, labio-oral and ear regions. In the regions with single measurements, identical values to NAW in forehead height, mouth width, and ear height were found in 99.7% in both sexes, while in those with multiple measurements, vertical measurements revealed a higher frequency of identical values than horizontal ones. The orbital regions exhibited the greatest variations in identical and contrasting measurements in comparison to NAW. Nose heights and widths contrasted sharply: in relation to NAW the nose was very or extremely significantly wide in both sexes of Asian and Black ethnic groups. Among Caucasians, nose height significantly differed from NAW in three ethnic groups, with one shorter and two greater. In the Middle Eastern groups nose width was identical to those of NAW but the height was significantly greater. The present study, conducted by investigators working separately across the world and with small samples of the population, is clearly preliminary in nature and extent. Yet it may fulfill its mission if medical and anthropological investigators continue the work of establishing normative data of the face. These data are urgently needed by medical professionals but have been lacking up till now in western and northern Europe, Asia, and Africa.  相似文献   
64.
The objective of this study was to investigate the beneficial effects of caffeic acid phenethyl ester (CAPE) on gentamicin (GM)-induced nephrotoxicity in Wistar rats. Twenty-one adult Wistar rats were divided into three groups as follows: control group, GM and GM + CAPE group. Control group rats were injected with 5% ethanol, GM group rats were treated with 100 mg/kg GM and GM + CAPE group were pretreated with 10 mumol/kg CAPE for 2 days, then exposed to GM at the same dose. Drug injections were applied for 12 days. Twenty-four hours after the last injection, rats were killed and kidneys were quickly removed. Tissue malondialdehyde (MDA) measurements and microscopic examination of kidneys were performed. In the GM group, significant increases in MDA levels were observed (P < 0.05). These changes were found to be normalized in the GM + CAPE group. Exposure to GM caused necrosis of tubular epithelial cells. Necrosis of tubules were found to be prevented by CAPE pretreatment. In conclusion, CAPE exerted an improvement on GM-induced nephrotoxicity, possibly, at least in part through inhibition of the production of oxygen free radicals that cause lipid peroxidation.  相似文献   
65.
Endometriosis is traditionally defined as the presence of endometrial glands and stroma in ectopic locations, especially the pelvic peritoneum, ovaries and rectovaginal septum. YKL-40, a new biomarker of inflammation, is secreted by activated macrophages and neutrophils in different tissues with inflammation. Serum concentrations of YKL-40 are elevated in patients with diseases characterized by inflammation. We aimed to investigate the possible association between serum YKL-40 levels and endometriosis. A total number of 88 women were recruited for this case–control study. About 53 patients with surgically proven endometriosis were included, while 35 patients without endometriosis comprised the control group. Patients were classified as having minimal, mild, moderate and severe disease in accordance with the severity. Two new groups were formed by combining patients with minimal and mild disease (Stage 1–2) and with moderate and severe disease (Stage 3–4). Serum YKL-40 levels were statistically higher in the endometriotic group compared to control group (p:0.001). YKL-40 levels were significantly higher in Stage 3–4 group compared to Stage 1–2 group (p values 0.001) as well. Correlation analysis revealed a positive correlation between serum YKL-40 levels and the stage of the disease. YKL-40 may be utilized as a marker for determining the severity of endometriosis.  相似文献   
66.
Cis-platin and other platinum complexes are important chemotherapeutic agents useful in the treatment of several cancers. However, therapeutic usage of cis-platin and other platinum complex are limited by their undesirable side effects including cardiotoxicity. In this context, we aimed to compare the damage caused in heart by cis-platin and novel platinum-N-heterocyclic carbene (Pt-NHC) complex. For this purpose, 35 Sprague-Dawley rats were divided randomly into five equal groups (n = 7 for each group). Cis-platin and novel Pt-NHC complex were intraperitoneally administered at a single dose of 5 mg/kg and 10 mg/kg and then sacrificed 10 days after this treatment. The heart tissues were taken from all rats for determination of oxidative and myocardial damage. Cis-platin and novel Pt-NHC complex caused oxidative and histological damage in the heart tissue in a dose-dependent manner (p < 0.05). On the other hand, at the same dose levels, cis-platin caused lower oxidative and histological damage in heart tissue compared to novel Pt-NHC complex. These results suggest that novel Pt-NHC complex is more cardiotoxic than cis-platin.  相似文献   
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69.
The interdomal fat pad (IFP) is an important structure related to tip deformity in rhinoplasty. This study aimed to evaluate the IFP by ultrasonography before surgery, and to demonstrate the existence of the IFP as a distinct anatomic structure in cadavers and patients. Three dimensions of the IFP were measured in 23 patients using ultrasound before rhinoplasty and in 10 cadavers using dissection. All fat pads were examined by histopathologic methods. In the cadavers, three dimensions of the IFP were found: 2.3 × 3.7 × 12.8 mm. In the patients, three dimensions of IFP were measured by ultrasonography: 2.8 × 4.1 × 13.7 mm. Histopathologic examinations showed that the IFP is a structure differentiated from subcutaneous tissue. The IFP was demonstrated in all cadavers and patients by surgical and radiologic methods. All cases had a fat pad in the interdomal space with varying sizes.  相似文献   
70.
Catastrophic cognitions are theorized to be an important construct for the development and maintenance of panic disorder with or without agoraphobia. However, there is a lack of reliable and valid self-report instruments for measuring catastrophic cognitions. This study presents the development and validation of the Catastrophic Cognition Questionnaire (CCQ) using 507 students from introductory psychology classes. Factor Analysis yielded a five-factor solution, which accounted for 54% of the total variance. The five are the Emotional, Physical, Mental, Social, and Bodily Catastrophes factors. The CCQ shows good reliability with Cronbach's Alpha for individual scales ranging from .86 to .94. The CCQ has good discriminant validity and correlates moderately with other self-report questionnaires that measure anxiety and cognitions associated with anxiety problems.  相似文献   
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