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1.
Cevval Ulman Semra Gezer Özden Anal I. Ruhi Töre Üzeyir Kirca 《Water, air, and soil pollution》1998,101(1-4):411-416
Arsenic, an environmental pollutant, is present in minute but invariable amounts in food, drinking water and ambient air. Izmir is founded on a land of long extinct volcanoes, with vast areas of lava ground suitable for agriculture. It is located at close vicinity to high thermal activity, e.g., hot springs and thermal baths. In the present study, total arsenic level in breast milk was assessed in randomly chosen 35 lactating women of different socioeconomic levels who live downtown in Izmir and in milk of 36 cows grazing on shoulder grass of highways with heavy traffic. Total arsenic was assessed on an atomic absorption spectrophotometer (AA-680 Shimadzu). Mean (± SEM) arsenic was found to be 4.219 ± 0.079 µg L-1 in breast milk, and 4.932 ± 0.38 µg L-1 in cow's milk. Conclusion: in Izmir, arsenic contamination of breast milk was not found so as to be considered noxious for suckling infants, whereas was found relatively higher in cow's milk. It would be prudent to remember breast and cow's milk arsenic contamination in breast fed or milk fed babies living in areas with higher thermal activity or in regions where ground water is with high arsenic content. 相似文献
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Bisphenol A (BPA), diethylhexyl phthalate (DEHP) and pentabrominated diphenyl ether 99 (PBDE 99) are environmental toxicants belonging to the endocrine disrupting compounds (EDCs). They exert adverse effects on the various physiological systems, especially the reproductive system of humans and animals. The aim of this study was to investigate the effects of BPA, DEHP and PBDE 99 on progesterone (P4) synthesis in cultured bovine luteal cells. The bovine luteal cells isolated from the mid-luteal corpora lutea were exposed to different concentrations of BPA (1, 3, 10 and 30 µM), DEHP (1, 3, 10 and 30 µM) and PBDE 99 (0.1, 0.3, 1 and 3 µM) in a serum-free culture media for 48 and 96 hr. At 48 hr, the P4 level in the luteal cells decreased after treatment with all concentrations of BPA; 3, 10 and 30 µM of DEHP; and 3 µM of PBDE 99 compared to the control (p < .05). Treatment of cells with 3–30 µM of BPA, 1–30 µM of DEHP and 1–3 µM of PBDE 99 for 96 hr resulted in reduction in P4 synthesis (p < .05). However, lower concentrations of PBDE 99 (0.1 and 0.3 µM) increased P4 levels at 48 and 96 hr. Synthesis of P4 was lower at 96 hr compared to the 48 hr in the groups treated with BPA (30 µM), DEHP (1–30 µM), PBDE 99 (0.3–3 µM) and control group. Our results showed that BPA, DEHP and PBDE 99 are able to alter luteal steroidogenesis in bovine cells and can disrupt hormonal balance in the ovary. However, it is necessary to evaluate the exact mechanism underlying these effects in future studies. 相似文献
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Kabakci N Yarim M Karahan S Guvenc T Yagci BB Gurcan IS 《Acta veterinaria Hungarica》2004,52(3):327-337
The cerebella of 21 dogs with canine distemper virus (CDV) infection and four normal dogs were examined histopathologically and immunohistochemically. Cerebella of CDV-infected dogs showed nonsuppurative demyelinating encephalomyelitis, classified as acute, subacute or chronic. Immunolocalisation of CDV antigen also confirmed the infection. Tissues were examined for co-localisation of the CDV antigen with either an astrocyte-specific marker, glial fibrillary acidic protein (GFAP), or an oligodendrocyte-specific marker, galactocerebroside (GalC). Immunoreactive cells were counted in demyelinating areas of the white matter. The number of astrocytes (GFAP positive) was significantly (p < 0.05) higher in CDV-infected dogs compared to controls. In contrast, the number of oligodendrocytes (GalC positive) was significantly (p < 0.001) lower in CDV-infected dogs and was much lower in chronic cases (p < 0.05). Approximately 41% of astrocytes and 17% of oligodendrocytes were immunoreactive for CDV. The ratio of CDV-infected oligodendrocytes and astrocytes remained almost constant during the progression of the disease (P > 0.05). In conclusion, CDV infects both astrocytes and oligodendrocytes. The gradual loss of oligodendrocytes is most likely responsible for the progressive demyelination in CDV infection. Astrocytosis in CDV infection should be further investigated if it occurs to stimulate oligodendrocytes for myelin production to compensate for the loss or to induce oligodendrocyte degeneration. 相似文献
4.
Yasar Emekli Ruhi Bastug Dursun Buyuktas Nefise Yasemin Emekli 《Agricultural Water Management》2007,90(3):205-212
This study was conducted to assess crop water stress index (CWSI) of bermudagrass used widely on the recreational sites of the Mediterranean Region and to study the possibilities of utilization of infrared thermometry to schedule irrigation of bermudagrass. Four different irrigation treatments were examined: 100% (I1), 75% (I2), 50% (I3), and 25% (I4) of the evaporation measured in a Class A pan. In addition, a non-irrigated treatment was set up to determine CWSI values. The status of soil water content and pressure was monitored using a neutron probe and tensiometers. Meanwhile the canopy temperature of bermudagrass was measured with the infrared thermometry. The empirical method was used to compute the CWSI values. In this study, the visual quality of bermudagrass was monitored seasonally using a color scale. The best visual quality was obtained from I1 and I2 treatments. Average seasonal CWSI values were determined as 0.086, 0.102, 0.165, and 0.394 for I1, I2, I3, and I4 irrigation treatments, respectively, and 0.899 for non-irrigated plot. An empirical non-linear equation, Qave=1+⌊6[1+(4.853 CWSIave)2.27]−0.559⌋, was deduced by fitting to measured data to find a relation between quality and average seasonal CWSI values. It was concluded that the CWSI could be used as a criterion for irrigation timing of bermudagrass. An acceptable color quality could be sustained seasonally if the CWSI value can be kept about 0.10. 相似文献
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Kul O Karahan S Basalan M Kabakci N 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2006,53(3):123-128
Polioencephalomalacia (PEM) in ruminants has been recognized as a consequence of excess sulphur intake. The present study describes clinical, gross and histopathological findings of PEM following an abrupt change of diet in two ranches housing 2750 dairy and 2300 beef cattle. As a result of severe PEM, 256 cattle died or were slaughtered. Clinical findings included circling, hypersensitivity, excessive salivation, hypermetria, incoordination, blindness and death. The first clinical signs occurred in beef calves (6-8 months old) at a holding facility. Clinical signs of the disorder continued intermittently during the 5-month period in both ranches and were more evident in calves and lactating dairy cows. The affected cattle did not respond to thiamine injections. Clinical signs disappeared gradually following removal of barley malt sprouts from the diet. Although macroscopic lesions were not apparent in the brain tissues of some animals, histopathology typical of PEM was found in most cases: spongiosis in the neuropil and neuronal necrosis, haemorrhage, capillary hyperplasia, fibrinoid degeneration in arterioles, multifocal liquefaction necroses in the grey matter and abundance of gitter cells with vacuolar large cytoplasm. Sulphide in rumen fluid of a clinically affected animal was measured as 1.55 mg/dl, which is considerably higher than that collected from two control cows (mean 0.21 mg/dl). The total sulphur content of the diet containing barley malt sprouts was estimated to be 0.45%, which is also higher than the National Research Council (NRC) maximum tolerable levels. In conclusion, PEM can result from excess barley malt sprout intake because of its higher sulphur content. Clinical signs may occur shortly after the intake of barley malt sprout as outbreaks with a higher number of deaths or as an ongoing periodic condition. 相似文献
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Oğuz Kul Nalan Kabakci Kader Yildiz Naci Öcal Hakan Kalender N. Aycan İlkme 《Veterinary parasitology》2009
Neospora caninum, a protozoan parasite, has been considered as one of the most important etiological agents responsible for abortion in dairy cattle throughout the world since it was first identified in dogs in 1988. In this report, characteristics of neosporosis, detected in a dairy cow ranch having epidemic abortions as high as 18.4%, were described. Blood samples were collected from 25 infertile or aborted dairy cattle, 6 calves born in 2006 and 40 heifers that were born in 2005 and raised in the same ranch. Necropsy was conducted in a 20-day-old Simmental calf that exhibited neurological signs including incoordination, head shaking, hyperextension in forelimbs and hindlimbs and tremor. The seroprevalance in aborted or infertile dairy cattle, heifers, and calves was 60%, 40%, and 33.3%, respectively. The mothers of seropositive two calves including clinically affected calf and its dam were N. caninum seropositive. In immunoperoxidase examinations, N. caninum antigen immunopositivity was observed in the degenerative and necrotic neurons in the brain, cerebellum as well as neurons in dorsal root ganglia of the cervical and thoracic regions of the spinal cord. In the heart, myocytes and Purkinje cells exhibited granular and linear patterns of immunoreactivity. Striated myofibers around the eyeball also showed immunolocalization for N. caninum antigen. Ultrastructurally, tachyzoites with typical apical complex, rhoptries and double-layered parasitic membrane were detected in the brain and heart sections. In conclusion, this report described clinical neosporosis for the first time in Turkey with tissue localization of the causative agents. This scientific communication also discusses the possible impact of cattle neosporosis by clinical, serologic and pathologic evidences collected from the survey of calves born in two successive generations in a ranch. 相似文献
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The enzyme 3beta-hydroxysteroid dehydrogenase (3beta-HSD) is essential in the synthesis of all steroids by cleaving dehydroepiandrosterone to androstenedione. In the present study, 3beta-HSD immunoreactivity was investigated in the prostate of Akkaraman breed rams aged older than 3 years. Five normal and five hyperplastic ram prostates were processed for immunohistochemistry. Prostate hyperplasia was determined by histopathological evaluation of 375 ram prostate and confirmed with significantly (P<0.01) increased number of cells expressing proliferating cell nuclear antigen (PCNA) immunoreactivity in the glandular epithelia. The 3beta-HSD immunoreactivity with a variable intensity and pattern of distribution was present in the glandular epithelia and endothelia of blood vessels in normal and hyperplastic ram prostates. While immunoreactivity was focally present in some glands, some sections had a homogenous distribution. The presence of 3beta-HSD immunoreactivity indicates that steroids are locally synthesized in the ram prostate. No differences in the distribution pattern of 3beta-HSD immunoreactivity and the percentage of immunoreactive cells were observed between normal and hyperplastic prostates (P>0.05), suggesting that locally produced steroids have little or no effect on the pathogenesis of the ram prostate hyperplasia which affects a very small proportion of the ram population (5 out of 375). 相似文献
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The cerebellum is a steroidogenic organ that expresses steroidogenic enzymes and produces neurosteroids. Purkinje neurones appear to be the most active steroidogenic cells in the cerebellar cortex. These neurones express 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD), P450 side-chain cleavage (P450scc), 17 alpha-hydroxylase/c17, 20lyase (P450c17), P450 aromatase (P450arom) and produce pregnenolone, progesterone, dehydroepiandrosterone, androstenedion, oestradion and oestrone. Oligodendrocytes are predominantly the producer of myeline protein. The oligodendrocytes were identified by immunohistochemistry using a monoclonal antibody against myeline 2', 3'-cyclic nucleotide 3'-phosphodiesterase (CNPase), a myeline specific enzyme. In this study we have examined the distribution of 3 beta-HSD and CNPase by immunohistochemistry using monoclonal antibody in canine cerebellar cortex. The localization of oligodendrocytes within the cerebellar cortex was determined to be close to Purkinje neurones. This result suggests that endogenous progesterone synthesized de novo in the Purkinje neurone can promote myeline protein synthesis in oligodentrocytes. 相似文献
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