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41.
42.

Background/Purpose

The aim of this study was to evaluate the effects of maternal nicotine exposure during gestation on injury severity of small intestine in the newborn rats subjected to hypoxia-reoxygenation and cold stress.

Methods

A total of 21 Sprague-Dawley pregnant rats were divided into 3 equal groups. The groups were labeled as group 1, control group; group 2, hypoxia-reoxygenation group; and group 3, nicotine-hypoxia-reoxygenation group. The rats of group 3 were exposed to nicotine via subcuticular injection for the last week of gestation (2 mg/kg/d). Newborn rats were collected immediately after birth to prevent suckling of maternal milk (40 rat pups in group 1, 43 rat pups in group 2, and 41 rat pups in group 3). Litters in groups 2 and 3 were stressed twice daily with asphyxia followed by cold (4°C for 10 minutes) stress to induce hypoxic intestinal injury which is relevant to human necrotizing enterocolitis. Breathing 100% CO2 for 10 minutes in a chamber followed by 10-minute 100% O2 breathing was the asphyxia model repeated twice daily. After hypoxia-reoxygenation and cold stress, newborn rats were returned to their mother's cages. This protocol was repeated for the following 2 days, and the rat pups were decapitated on the third day. Using this protocol of asphyxia and cold stress, all of neonatal rats developed clinical and pathological signs of hypoxia-induced intestinal injury. The entire gastrointestinal tract was removed and examined macroscopically. A 2-cm section of distal ileum from each animal was taken for histopathological and biochemical examinations. Histological changes in ileal architecture were scored and graded from 1 to 5. The remaining intestinal tissues of the animals were used for lipid peroxidation analysis.

Results

Typical signs of hypoxia-induced intestinal injury were observed in the 2 experimental groups (groups 2 and 3) macroscopically. There were more grades 3 and 4 injuries in group 3 (P < .05). The malondialdehyde levels were elevated in groups 2 and 3 (P < .001). The malondialdehyde levels of the group 3 were also significantly higher than group 2 (P < .01).

Conclusions

Maternal nicotine exposure during gestation results in higher grade histological injury in newborn rats subjected to hypoxia-reoxygenation and cold stress.  相似文献   
43.
BACKGROUND: The aims of this study were to determine the presence of trefoil factor family-3 (TFF3) expression in biliary epithelial cells (BECs) of chronic graft-versus-host disease (cGVHD) of the liver after allogeneic hematopoietic cell transplantation, to compare such expression in chronic liver diseases (CLD) with/without predominantly biliary disease, and to assess the effect of bile duct injury on the degree of TFF3 expression in BECs of cGVHD. METHODS: A total of 82 paraffin-embedded liver biopsy samples were reviewed. These samples were basically divided into two distinct groups according to the presence of ductal injury: group 1 with CLD and predominantly biliary disease (n=26: 17 cGVHD and 9 primary biliary cirrhosis [PBC]) and group 2 with CLD and predominantly parenchymal liver disease (n=56: 20 steatohepatitis and 36 chronic viral hepatitis). Group 2 was used as the controls. Immunohistochemistry was performed using a polyclonal anti-TFF3 antibody. Real-time quantitative PCR was used for the detection of TFF3 mRNA expression. RESULTS: Positive TFF3 immunohistochemical staining and the presence of TFF3 messenger RNA gene expression was demonstrably higher in group 1 than that in group 2 (P<0.0001 and P<0.05, respectively). No significant difference in terms of positive TFF3 stained BECs between GVHD and PBC samples was observed (P>0.05). The extent of TFF3 expression in GVHD samples with severe ductal injury were significantly more common than that of GVHD samples with mild/moderate ductal injury (P<0.0001). CONCLUSIONS: The expression of TFF3 in cGVHD of the liver is increased in response to bile duct damage and repair. Such expression seems to be related the severity of ductal injury.  相似文献   
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Ultrasonographic examinations of both hips of 133 children whose age ranged from 13 to 72 months were performed using the Graf's method. A standard plane which was mandatory prior to the hip typing could be obtained in 93, 91, 84, 79 and 66% of the sonograms for 13-24, 25-36, 37-48, 49-60 and 61-72 months age groups, respectively. The 61-72 months age group had the lowest percentage of valid sonograms and this difference was considered significant (P=0.001). It was concluded that plain radiography was still the gold standard imaging technique in developmental dysplasia of the hip, but hip ultrasonography by the Graf's method might be an alternative imaging technique in experienced hands for the evaluation of developmental dysplasia of the hip in children between 1 and 5 years of age.  相似文献   
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OBJECTIVE: The purpose of this study was to determine the levels of adrenomedullin (AdM) in amniotic fluid (AF) and maternal serum of misoprostol (PGE1)-induced pregnant women. MATERIALS AND METHODS: A total of 40 women were included in the study: 20 were in active labor and were delivered vaginally and a further 20 were not in labor and misoprostol induction was performed. Women who were undergoing labor induction received 50 microg of misoprostol, which was placed in the posterior fornix of the vagina every 4 hrs until the onset of labor. In each patient, maternal plasma and AF samples were collected. Samples of AF were collected by transvaginal route at the time of rupture of the membranes. The labor was at the same stage in both the groups during the sample collection. In all pregnant subjects, maternal blood samples were drawn from the cubital vein at the time of AF sampling. Amniotic fluid and serum AdM concentration was measured by using reverse-phase high-performance liquid chromatography. RESULTS: Misoprostol-induced pregnant women showed significantly higher AdM concentrations than control pregnant women in AF (79.48 +/- 6.14 pmol/ml versus 21.28 +/- 0.90 pmol/ml, P = 0.000) and maternal serum (88.20 +/- 4.34 pmol/ml versus 29.78 +/- 4.51 pmol/ml, P = 0.000). There was no significant difference between maternal serum and AF-AdM concentrations in misoprostol and control subjects. CONCLUSION: Increased serum and AF-AdM concentrations may be necessary to initiate cervical ripening in misoprostol-induced pregnant women.  相似文献   
48.
A 4-year-old boy was referred for scintigraphic evaluation of esophageal transit 24 hours after he had ingested sodium hydroxide. After oral administration of Tc-99m sulfur colloid, scintigraphy showed marked and prolonged retention of the radioactive bolus in the middle and lower thirds of the esophagus. Three weeks after ingestion of the caustic substance, repeat scintigraphy was requested to evaluate esophageal transit and gastric-emptying. In this presentation, a tracheoesophageal fistula was a consequence of sodium hydroxide ingestion and was identified with radionuclide scintigraphy before there was clinical and radiologic detection.  相似文献   
49.
In this study, short-time Fourier transform (STFT) and wavelet transform (WT) were used for spectral analysis of ophthalmic arterial Doppler signals. Using these spectral analysis methods, the variations in the shape of the Doppler spectra as a function of time were presented in the form of sonograms in order to obtain medical information. These sonograms were then used to compare the applied methods in terms of their frequency resolution and the effects in determination of spectral broadening in the presence of ophthalmic artery stenosis. A qualitative improvement in the appearance of the sonograms obtained using the WT over the STFT was noticeable. Despite the qualitative improvement in the individual sonograms, no quantitative advantage in using the WT over the STFT for the determination of spectral broadening index was obtained due to the poorer variance of the wavelet transform-based spectral broadening index and the additional computational requirements of the wavelet transform.  相似文献   
50.
BACKGROUND: This study was conceived to evaluate the effect of carbon dioxide insufflation on free internal thoracic artery flows. METHODS: We studied 56 consecutive patients who underwent coronary artery bypass grafting in which the left internal thoracic artery was anastomosed to the left anterior descending artery. The first 26 consecutive internal thoracic arteries were harvested as a pedicled graft (group 1), and the next 30 consecutive internal thoracic arteries were dissected by using the carbon dioxide insufflation technique (group 2). The internal thoracic artery harvesting was performed by 2 experienced surgeons by using the same instrumentation and technique. First, free flows of the internal thoracic arteries were registered after distal cutting of the vessel in both groups. After the first measurements, diluted papaverine was sprayed on the internal thoracic artery pedicle only in group 1, and then second measurements were registered after 15 minutes in both groups. Hemodynamic parameters were recorded with each measurement. RESULTS: The first free flow measurement was significantly higher in the carbon dioxide-insufflated internal thoracic arteries (group 2, 60 +/- 32 mL/min; group 1, 28 +/- 19 mL/min; P <.05). Although the second free flow measurement of the carbon dioxide-insufflated group was higher than in group 1, the difference was not statistically significant (68 +/- 46 mL/min vs 53 +/- 32 mL/min; P =.53). CONCLUSIONS: Carbon dioxide insufflation of the internal thoracic artery is an efficient technique to increase the flow and seems to be safe, simple, and reliable. When the internal thoracic artery is harvested in a carbon dioxide-insufflated fashion, arterial spasm and reduced early flow may be avoided, even without vasodilator agents such as papaverine.  相似文献   
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