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21.
Suppression of Immune Parameters in Animal Models of Morphine Dependence   总被引:3,自引:0,他引:3  
Implantation of pellets containing 75 mg of morphine induced short term (4 day) morphine dependence and markedly reduced total number of spleen cells of BALB/c mice, without affecting total body or liver weight. Polyclonal responses induced by anti-CD3 antibodies, Concanavalin A or Escherichia coli lipopolysaccharide in the remaining spleen cells of morphine-treated mice were also inhibited. Cytofluorimetric analysis indicated that the proportion of major functional lymphocyte populations (Ig+, CD3+, CD4+ and CD8+ lymphocytes) were not significatively changed in the spleen from morphine-dependent mice. Furthermore, expression levels of surface Ig, CD3, CD4, and CD8, were similar in spleen cells from control or morphine-treated mice. So, morphine dependence in BALB/c mice under these controlled conditions results in a specific defect in lymphoid cell number and function, with no incidence on body weight or particular lymphocyte subsets.  相似文献   
22.

Objective

Preterm infants, especially those born very preterm (< 32 weeks' gestation), suffer a number of morbidities. Immaturity of the endocrine system and its potential impact on morbidity is the subject of numerous studies. Hormone concentrations are sometimes measured in very preterm infants, however there are little normative data available to be able to interpret the results. The aim of this study was to describe age appropriate hormone reference intervals for babies born less than 30 weeks' gestation.

Study design

Samples were collected at 1, 4, 7, 14, 21, 28 and 42 days after birth from babies born 23–29 weeks' gestation. The serum was analyzed for seven hormones by automated chemiluminescent immunoassay (Siemens Immulite 2000). Results from the 107 infants who survived beyond 40 weeks' corrected gestational age were included in the data analysis.

Results

Cortisol, dehydroepiandrosterone sulfate, growth hormone and progesterone levels were highest during the first seven days with levels up to 10,801 nmol/L; 26.6 μmol/L; 343 mU/L; and > 63.6 nmol/L respectively. Free thyroxine levels were as low as < 2.6 pmol/L for the first 28 days with the nadir at 7 days. Estradiol levels ranged from < 73 to 1626 pmol/L over the six weeks. Reference intervals for IGF-1 could not be established as the levels were below the analyzer's sensitivity. There were no differences in reference intervals between male and female infants.

Conclusions

We describe gestation appropriate reference intervals for six hormones measured in babies born < 30 weeks' gestation. Utilization of these reference intervals permits the correct and timely interpretation of results to the clinician.  相似文献   
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BACKGROUND: L-Buthionine (S,R) sulfoximine (BSO) is an inhibitor of glutathione biosynthesis and has been used as an effective means of depleting glutathione from cells and tissues. Here we investigated whether treatment with BSO enhanced ethanol-induced liver injury in mice. METHODS: Female C57Bl/6 mice were pair fed with control and ethanol-containing liquid diets in which ethanol was 29.2% of total calories. During the final 7 days of pair feeding, groups of control-fed and ethanol-fed mice were given 0, 5 or 7.6 mM BSO in the liquid diets. RESULTS: Compared with controls, ethanol given alone decreased total liver glutathione. This effect was exacerbated in mice given ethanol with 7.6 mM BSO, causing a 72% decline in hepatic glutathione. While ethanol alone caused no decrease in mitochondrial glutathione, inclusion of 7.6 mM BSO caused a 2-fold decline compared with untreated controls. L-Buthionine (S,R) sulfoximine did not affect ethanol consumption, but serum ethanol levels in BSO-treated mice were nearly 6-fold lower than in mice given ethanol alone. The latter decline in serum ethanol was associated with a significant elevation in the specific activities of cytochrome P450 2E1 and alcohol dehydrogenase in livers of BSO-treated animals. Ethanol consumption caused a 3.5-fold elevation in serum alanine aminotransferase levels but the enzyme fell to control levels when BSO was included in the diet. L-Buthionine (S,R) sulfoximine administration also attenuated ethanol-induced steatosis, prevented the leakage of lysosomal cathepsins into the cytosol, and prevented the ethanol-elicited decline in proteasome activity. CONCLUSIONS: L-Buthionine (S,R) sulfoximine, administered with ethanol, significantly depleted hepatic glutathione, compared with controls. However, despite the decrease in hepatic antioxidant levels, liver injury by ethanol was alleviated, due, in part, to a BSO-elicited acceleration of ethanol metabolism.  相似文献   
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Normal human immunoglobulin G (IgG) has anti-inflammatory and immuno-regulatory properties, which are exploited in the therapy of selected diseases. A putative mechanisms of action is the direct regulation of endothelial cell function by natural antiendothelial cell antibodies. Endothelium activation is a critical event in atherosclerosis. We have verified the ability of normal human IgG to modulate endothelial responses to the atherogenic stimuli tumour necrosis factor-alpha (TNFalpha) and oxidized low-density lipoproteins (oxLDL) in vitro. Confocal microscopy was used to visualize vascular cell adhesion molecule-1 (CD106) expression on endothelial cells, cytoplasmic free calcium ([Ca++]i) modifications and fluorescein-coupled oxLDL internalization. Cytokine secretion was measured by ELISA on cell supernatants. IgG prevented TNFalpha induced CD106 membrane expression and an increase in [Ca++]i, and inhibited the secretion of interleukin-6 (IL-6) and macrophage-colony-stimulating factor (M-CSF). IgG also inhibited CD106 expression induced by oxLDL and one pathway of their internalization, but were ineffective on oxLDL induced [Ca++]i rise and apoptosis. F(ab)'2 fragments from IgG, but not monoclonal IgG, reproduce IgG effects. These findings point to a regulatory role for specific antibodies included in circulating normal IgG towards proinflammatory responses of endothelial cells in atherogenesis and suggest possible development of new therapeutic strategies.  相似文献   
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29.
Midfacial necrosis due to the abuse of inhaled cocaine is a new entity that is included in the differential diagnosis of the midline destructive diseases such as Wegener's granulomatosis, polymorphic reticulosis, nasal lymphoma, infections and the idiopathic midline destructive disease. We report the case of a forty-year-old male who presented necrosis of the nasosinusal tract and optic neuropathy as complications due to the abuse of inhaled cocaine for more than twenty years and a discussion about the differential diagnosis.  相似文献   
30.
BACKGROUND: Needle localization breast biopsy (NLBB) is the standard for removal of breast lesions after vacuum assisted core biopsy (VACB). Disadvantages include a miss rate of 0% to 22%, a positive margin rate of approximately 50%, and vasovagal reactions (approximately 20%). We hypothesized that clip migration after VACB is clinically significant and may contribute to the positive margin rates seen after NLBB. METHODS: We performed a retrospective review of postbiopsy films in patients who had undergone VACB with stereotactic clip placement for abnormal mammograms. We measured the distance between the clip and the biopsy site in standard two view mammograms. The location of the biopsy air pocket was confirmed using the prebiopsy calcification site. The Pythagorean Theorem was used to calculate the distance the clip moved within the breast. Pathology reports on NLBB or intraoperative hematoma-directed ultrasound-guided breast biopsy (HUG, which localizes by US the VACB site) were reviewed to assess margin status. RESULTS: In all, 165 postbiopsy mammograms on patients who had VACB with clip placement were reviewed. In 93 evaluable cases, the mean distance the clip moved was 13.5 mm +/- 1.6 mm, SEM (95% CI = 10.3 mm to 16.7 mm). Range of migration was 0 to 78.3 mm. The median was 9.5 mm. In 21.5% of patients the clip was more than 20 mm from the targeted site. Migration of the clip did not change with the age of the patient, the size of the breast or location within the breast. In the subgroup of patients with cancer, margin positivity (including those with close margins) after NLBB was 60% versus 0% in the HUG group. CONCLUSIONS: Significant clip migration after VACB may contribute to the high positive margin status of standard NLBBs. Surgeons cannot rely on needle localization of the clip alone and must be cognizant of potential clip migration. HUG as an alternative biopsy technique after VACB eliminates operator dependency on clip location and may have superior results in margin status.  相似文献   
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