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1.
Gibberellic acid (GA?) has been worldwide used in agriculture as a plant growth regulator. The purpose of this study is to assess the effects of GA? on the morphology and the thyroid hormone levels in adult rats and their suckling pups. Animals were given daily 200 ppm GA? in drinking water from the 14th day of pregnancy until day 14 after delivery. Compared with a control group, GA?-treated mothers and pups showed an increase in body and thyroid weights, a decrease in plasma FT? and FT? levels, which were more pronounced in pups than in their mothers. Thyroid iodine content was also decreased in pups. These biochemical modifications corresponded histologically; the majority of follicles had cubical epithelial cells, which surrounded empty vesicular cavities. Toxicity was objectified by a significant increase in plasma malondialdehyde, protein carbonyls, and advanced oxidation protein products levels in GA?-treated dams and their suckling pups; while, the activities of superoxide dismutase, catalase, and glutathione peroxidase were decreased in plasma of both dams and their pups. Moreover, a significant decline was observed in plasma glutathione, nonprotein thiols, and vitamin C levels. We conclude that GA? treatment affects thyroid function and plasma antioxidant status in adult rats and their progeny.  相似文献   
2.
A small, mosaic, C-band negative marker chromosome was detected in amniocyte cultures during prenatal diagnosis due to advanced maternal age. Following spontaneous premature labor at 29 weeks gestation, a dysmorphic infant was delivered, with flat nasal bridge, short palpebral fissures, micrognathia, high forehead, low-set ears, telecanthus and corneal dystrophy. Additional folds of skin were present behind the neck, and feet, fingers and toes were abnormally long. The child died at age five days, after two days of renal failure. The origin of the marker chromosome was subsequently identified from a cord blood sample, via chromosome microdissection. Through reverse FISH, we found the marker to be an inverted duplication of the region 15q26.1-->qter. FISH with alphoid satellite probe was negative, while whole chromosome 15 paint was positive. Both ends of the marker chromosome were positive for the telomeric TTAGGG probe. These data, plus the G-banding pattern, identified the marker as an analphoid, inverted duplicated chromosome, lacking any conventional centromere. We discuss the etiology and clinical effects of this marker chromosome, comparing it to the few reported cases of "tetrasomy 15q" syndrome. We also discuss the possible mechanisms that are likely responsible for this neocentromere formation.  相似文献   
3.
S. Mansouri  H. Mahjoubi  R. Ben Salah 《IRBM》2010,31(5-6):280-288
The objective of this article is the design of a prototype allowing the determination of the cardiovascular parameters by a noninvasive method, the peripheral bioimpedance. The prototype is designed with the National Instruments PXI- 7841R data acquisition card, the NI PXI-1033 chassis, the NI SCB-68 connector block and the software of development, LabVIEW with its LabVIEW FPGA module. The core of the PXI-7841R is an FPGA target, the Xilinx Virtex-5 LX30. The configuration of FPGA was not made by VHDL but rather by graphic programming with the LabVIEW FPGA. This module offers the possibility of an easy, sure and fast design. The results of the design are very satisfactory and allowed us to have a completely reconfigurable and evolutionary system fulfilling the electric safety requirements of biomedical equipments. The system allows moreover the determination of several cardiovascular parameters and can be used as vital signs monitor.  相似文献   
4.
l-Gulono-gamma-lactone oxidase (GULO) is a key enzyme for the biosynthesis of ascorbate, which is essential for several cellular functions. In the present study, mRNA expression of GULO gene was evaluated during the early development of Persian sturgeon. First, because there are no comparative studies that have established suitable quantitative real-time PCR reference genes in sturgeons for any physiological conditions, we evaluated six candidate reference genes (ACTB, RPL13, UBQ, RPL6, GAPDH and EF1A) during the early development of Persian sturgeon. The most stable mRNA expression was obtained with RPL6 and ACTB, whereas the least stable was RPL13. After normalization using RPL6, ACTB and RPL6/ACTB combination, the mRNA expression of GULO was highest at the embryonic stage (2days before hatching; P<0.05) and started to decline from hatching of larvae to the rest of the developmental time-points. This suggests that the vitamin C requirements are highest during early life stages, and it is likely that the changes in GULO mRNA expression are associated with changes in GULO enzyme activity.  相似文献   
5.
The aim of this study was to determine whether increasing a lipogenic nutrient (beet pulp; BP) at the expense of a glucogenic nutrient (barley grain; BG) can decrease the body condition score (BCS) of fat cows in late lactation. Eighteen lactating Holstein cows were used in a randomized complete block design. The cows were 171 ± 16.3 days in pregnancy, 289 ± 35.1 days in milk and 4.12 ± 0.351 BCS at the beginning of the study. Cows were assigned randomly to one of three dietary treatments containing: (1) 234.7 g/kg BG (without BP), (2) 148.7 g/kg BG (86 g/kg BP), or (3) 62.7 g/kg BG (172 g/kg BP). By adding BP, the starch (190.2, 151.0, and 123.3 g/kg DM) and NDFom (308.6, 319.3, and 337.9 g/kg DM) levels in the TMR changed. Substituting BG by BP didn’t affect yield of milk protein and lactose, but milk fat level and milk energy output increased as BP replaced BG. Adding BP caused BCS and back fat thickness to reduce. Plasma glucose and cholesterol decreased as BP substituted for BG. Results suggest that inclusion of BP in diets of fat cows during late lactation may slightly reduce BCS, and increase milk fat and energy levels, with no effect on milk yield.  相似文献   
6.
Circadian rhythm of irinotecan tolerability in mice   总被引:2,自引:0,他引:2  
The toxicity of irinotecan (CPT-11), a topoisomerase-I inhibitor largely used in cancer patients, was investigated as a function of the circadian time of its administration in mice, with mortality, body weight loss, leukopenia, neutropenia, intestinal lesions, and bone marrow cell cycle phase distribution as end points. Four experiments were performed on a total of 773 male mice standardized with 12h light/12h darkness. Irinotecan was administered daily for 4 or 10 consecutive days (D1-4 and D1-10, respectively, in different experiments) at one of six circadian stages expressed in hours after light onset (HALO). The survival curves differed significantly as a function of the dosage and circadian time of drug administration by the D1-10 schedule, with 70% survival at 7 or 11 HALO and 51% at 19 or 23 HALO (p=0.039 from log rank test). CPT-11 administration at 19 or 23 HALO resulted in (1) greatest mean body weight loss at nadir; (2) most severe colic and bone marrow lesions and/or slowest recovery; and (3) deepest neutropenia nadir and/or slowest hematologic recovery. These circadian treatment time-related differences were statistically validated. The bone marrow cell cycle data revealed a four to eight-fold larger G2-M phase arrest following irinotecan administration at 19 or 23 HALO in comparison to the other times of drug administration, apparently representative of the repair of more extensive DNA damage (p < 0.001 from ANOVA) when the medication was given at these circadian times. Overall, CPT-11 was better tolerated by mice treated during the light (animals' rest) span. The results support the administration of CPT-11 to cancer patients in the second half of the night, during sleep, in order to improve drug tolerability.  相似文献   
7.
8.

Nitric oxide (NO) is a signaling molecule controlling several steps of plant development and defense process under stress conditions. NO-induced alleviation of manganese (Mn) toxicity was investigated on bean plants submitted for 28 days to 500 µM MnCl2. Manganese excess decreased plant dry weight and elongation and increased levels of reactive oxygen species and lipid peroxidation leading to up-regulation of superoxide dismutase, catalase, and ascorbate peroxidase activities. The inhibitory effects of Mn on plant growth were associated to reduction of light-saturated carbon assimilation (Amax), stomatal conductance (gs), and transpiration (E). By contrast, Mn induced significant increase in the apparent quantum yield (ɸ) and light compensation point (LCP). Interestingly, intracellular CO2 (Ci) remains stable under Mn stress. Concomitantly, leaf membrane lipids have drastically reduced under high Mn concentration. After Mn exposition, leaf fatty acids exhibited a significant loss of linolenic acid, accompanied by an accumulation of palmitoleic, stearic, and linoleic acids leading to alteration of lipid desaturation. NO supply reversed Mn toxicity as evidenced by enhancement of growth biomass and recovery of Amax, E, ɸ, and LCP. Similarly, NO addition has positive effects on leaf lipid content and composition leading to restoration of lipid unsaturation. The modulation of fatty acid composition can be a way to reduce leaf membrane damages and maintain optimal photosynthesis and plant growth. Despite the absence of enough evidences in how NO is involved in lipid and photosynthesis recovery under Mn stress conditions, it is assumed that NO beneficial effects are attributable to NO/Mn cross-talk.

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9.
International Microbiology - The reemergence of infectious diseases and resistant pathogens represents a serious problem for human life. Hence, the screening for new or alternative antimicrobial...  相似文献   
10.
Gibberellic acid (GA3) is an endogenous plant growth regulator used worldwide in agriculture. The objective of this study was to investigate the effects of GA3 on the kidney function of adult rats and their pups. Female Wistar rats were given daily 200 ppm GA3 in drinking water from the 14th day of pregnancy until day 14 after delivery. GA3 induced nephrotoxicity, as evidenced by a reduction in the 24-h urine volume and an increase in plasma creatinine, urea and uric acid levels. Nephrotoxicity was objectified by a significant increase of malondialdehyde level and a decrease of antioxidant enzyme activities like catalase, superoxide dismutase, glutathione peroxidase and glutathione content in kidneys of suckling pups and their mothers. Kidney histological studies confirmed biochemical parameters. We concluded that the exposure of rats to GA3 induced oxidative stress and histopathological changes in kidneys of suckling rats and their mothers during late pregnancy and early postnatal periods.  相似文献   
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