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11.
Ultrastructural changes in the kidneys of rats after acute cadmium exposure and the effects of exogenous metallothionein (MT) were studied by transmission electron microscopy. Thirty-six adult Wistar rats were divided into three groups. Cadmium chloride (CdCl2) (3.5 mg/kg/day) was injected subcutaneously in the first group. In the second group, 30 μmol/kg MT was administered in addition to CdCl2. Control rats received 0.5 ml subcutaneous saline solution. Four rats from each group were killed on days 1, 3, 5, and 7 after administration of the compounds. Kidney tissues were taken and fixed in 2.5% glutaraldehyde solution for electron microscopic observations. Tissue damage in kidney increased as time passed since the administration of CdCl2 in the first group. Degeneration in the proximal and distal tubules was observed. Increased apoptosis was seen in the proximal tubules epithelium, especially on day 7. Peritubular capillaries became dilated, there was degeneration of the endothelial cells, and the amount of intertubular collagen fibers was increased. On day 1, irregular microvilli in the proximal tubules, deepening of the basal striations, and myelin figures; on day 3, multiple vesicular mitochondria and regions of edema around tubules; on days 5 and 7, increased apoptotic cell in the proximal tubules and widened rough endoplasmic reticulum of the endothelial cells of glomerular capillaries were observed. We observed that the structural alterations that increased depending on the day of Cd administration decreased after exogenous MT administration, the dilation of the peritubular capillaries persisted, and there were degenerated proximal tubules. It was established that cadmium chloride was toxic for kidney cortex and caused structural damage. Exogenous MT partly prevents CdCl2-induced damage.  相似文献   
12.
Isolated ACTH deficiency is an uncommon cause of secondary adrenocortical insufficiency and accompaniment with primary empty sella has been reported in several cases. We present a case of isolated ACTH deficiency associated with empty sella. A sixty-two year old woman was admitted to our endocrine clinic with complaints of weakness, fatigue, weight loss, nausea, vomiting, and lack of appetite for about one month. Physical examination indicated orthostatic hypotension and epigastric tenderness. Laboratory investigations revealed hypoglycemia, hyponatremia and anemia, in addition low plasma cortisole and ACTH levels. Serum cortisole responses to short and prolonged ACTH stimulation were tested and partial and accurate responses were obtained, respectively. Plasma ACTH and serum cortisole levels failed to respond after intravenous injection of human corticotropin releasing hormone. Other hypophysial hormone levels were within the normal reference ranges. Although cranial and abdominal computerized tomography images were evaluated as normal, cranial magnetic resonance imaging of the pituitary gland revealed 'primary empty sella turcica'. Replacement therapy with methylprednisolon resulted in the improvement of hypoglycemia, hyponatremia and clinical symptoms. Based on these results, the patient was diagnosed as isolated ACTH deficiency and was scheduled for follow up by our outpatient clinic. Our report is consistent with other reports pointing out that primary empty sella may be responsible for pathogenesis of isolated ACTH deficiency.  相似文献   
13.
We aimed to establish age-related reference values for Erythropoietin (EPO) in cerebrospinal fluid (CSF) and to evaluate concentrations in neurological diseases. CSF and serum EPO was measured in controls with tension-type headache (CTTH), in patients with ALS, dementia and depression using ELISA technique. Stability experiments showed CSF EPO to be stable for two and a half months and over two thaw/freeze cycles. A positive correlation of CSF EPO with age was found (P < 0.01). We found a CSF/serum EPO concentration ratio of 0.126, pointing towards an intrathecal synthesis of EPO. The ALS group showed significantly lowered CSF EPO compared to age-matched CTTH (P < 0.012), whereas the dementia and depression group showed no significant differences compared to CTTH. The establishment of age-related reference values in a large cohort of controls will improve the interpretation of future CSF EPO evaluations in neurological diseases. The authors have not reported any conflicts of interest.  相似文献   
14.
15.
The antimicrobial activity and the MIC values of the diethyl ether, acetone, chloroform, petroleum ether, and ethanol extracts of the lichen Hypogymnia tubulosa and its 3-hydroxyphysodic acid constituent have been investigated against some microorganisms. At least one of the extracts or 3-hydroxyphysodic acid showed antimicrobial activity against Aeromonas hydrophila, Bacillus cereus, Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, Listeria monocytogenes, Proteus vulgaris, Salmonella typhimurium, Staphylococcus aureus, Streptococcus faecalis, and Candida albicans. No antifungal activity of the extracts has been observed against ten filamentous fungi.  相似文献   
16.
The aim of present study was to investigate the effects of 3,3′,5-triiodothyronine (T3) on rat testis both morphometrically and immunohistochemically with determining of insulin-like growth factor I (IGF-I) expression. Adult male Wistar-albino rats used in the study were divided into two groups; control and T3-treated groups. After T3 treatment there was observed to be a decrease in testicular weights, diameters of seminiferous tubules and the number of sertoli cells, and an increase in the number of leydig cells (P<0.05). Some of the seminiferous tubule lumens of T3 administrated rats had cellular debris. IGF-I was localized in sertoli cells, late spermatids and leydig cells of all groups. IGF-I immunoreactivity in T3 treated rats was higher than in controls in all stages of the cycle of rat seminiferous epithelium, but the staining intensity of leydig cells were similar in both groups. In conclusion, the present results suggest that T3 may modulate the testicular function by affecting IGF-I activity at the gonadal level.  相似文献   
17.
Chrysin, apigenin, flavonoids, flavanones, naringenin, ethyl oleate, 3-4-dimethoxy-cinnamic acid and 9-octadecenoic acid were the predominant components of propolis samples collected from different regions of Turkey. The extracts of P3 from Denizli-Ba?karci, P5 from Denizli and P7 from Tekirda? had effective antibacterial activities on Gram-negatives. Chrysin, which has antibacterial activity, was found to be high concentration. The extracts of P3, P2B from Aydin and P6 from Konya had much more effective antibacterial activities on Gram-positives. The total antioxidant activity increased with the increasing amount of extracts added to linoleic acid emulsion. All doses of propolis ethanol extract displayed antioxidant activity.  相似文献   
18.
The antimicrobial activity and the MIC values of the ethanol, chloroform, diethyl ether, and acetone extracts of the chemical races of Pseudevernia furfuracea (var. furfuracea and var. ceratea) and their physodic acid, chloroatranorin, atranorin, and olivetoric acid constituents have been investigated against some microorganisms. Nearly all extracts of both chemical races showed antimicrobial activity against Aeromonas hydrophila, Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Proteus vulgaris, Staphylococcus aureus, Streptococcus faecalis, Yersinia enterocolitica, Candida albicans, Candida glabrata, Alternaria alternata, Ascochyta rabiei, Aspergillus niger, Fusarium culmorum, Fusarium moniliforme, Fusarium oxysporum, Fusarium solani, and Penicillium notatum. There was no antimicrobial activity of the extracts against Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Pseudomonas syringae, Salmonella typhimurium, Alternaria citri, Alternaria tenuissima, and Gaeumannomyces graminis. Chloroatranorin and olivetoric acid were active against the same microorganisms with few exceptions. Physodic acid was active against about the same bacteria and yeasts and inactive against all of the filamentous fungi tested. Also no activity of atranorin against the filamentous fungi was observed.  相似文献   
19.
New data and records of the genus Chrysotoxum Meigen, 1803 are reported, arising from taxonomic and faunistic examination of adult specimens collected from 1920 to 2011 from four northeastern provinces of Turkey (Erzurum, Bayburt, Kars, and Artvin), and from the neighboring countries of Armenia, Azerbaijan and Iran. Three new species are described: Chrysotoxum antennalis Vuji?, Nedeljkovi? &; Hayat sp. n., C. clausseni Vuji?, Nedeljkovi? &; Hayat sp. n. and C. persicum Vuji?, Nedeljkovi? &; Hayat sp. n. The first two are known only from northeastern Turkey, and the third also occurs in Armenia, Azerbaijan and Iran. These new species have in common an antenna with the basoflagellomere being shorter than the scape and pedicel together.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:4C264678-8E47-4DE0-AC7D-91DABC597BCD  相似文献   
20.
Loss of intracellular neuronal glutathione (GSH) is an important feature of neurodegenerative disorders including Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. The consequences of GSH depletion include increased oxidative damage to proteins, lipids, and DNA and subsequent cytotoxic effects. GSH is also an important modulator of cellular copper (Cu) homeostasis and altered Cu metabolism is central to the pathology of several neurodegenerative diseases. The cytotoxic effects of Cu in cells depleted of GSH are not well understood. We have previously reported that depletion of neuronal GSH levels results in cell death from trace levels of extracellular Cu due to elevated Cu(I)-mediated free radical production. In this study we further examined the molecular pathway of trace Cu toxicity in neurons and fibroblasts depleted of GSH. Treatment of primary cortical neurons or 3T3 fibroblasts with the glutathione synthetase inhibitor buthionine sulfoximine resulted in substantial loss of intracellular GSH and increased cytotoxicity. We found that both neurons and fibroblasts revealed increased expression and activation of p53 after depletion of GSH. The increased p53 activity was induced by extracellular trace Cu. Furthermore, we showed that in GSH-depleted cells, Cu induced an increase in oxidative stress resulting in DNA damage and activation of p53-dependent cell death. These findings may have important implications for neurodegenerative disorders that involve GSH depletion and aberrant Cu metabolism.  相似文献   
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