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151.
Lymphoma-bearing mice have a circulating lipid-mobilizing factor, but increased plasma free fatty acid (FFA) turnover has not been demonstrable in earlier studies using postabsorptive tumor-bearing mice. We hypothesized that FFA mobilization in lymphoma-bearing mice is only elevated in fed mice and may best be observed at night (dark, reversed light cycle). AKR mice with early and advanced tumors (10(6) SL-3 lymphoma cells, i.p.) and controls were fed ad libitum (reversed light cycle, dark) or fasted 4 h (daylight, regular cycle), given injections of [14C]bicarbonate of [1-14C]palmitate-mouse serum albumin, i.v., and plasma [14C]FFA disappearance and/or breath 14CO2 were monitored. Plasma FFA mobilization, estimated by multicompartmental analysis (SAAM) of the oxidation rate was lower in fasted mice with advanced tumors [tumor, 9.5 +/- 6.0% (%SE); controls, 14 +/- 4.4% micrograms-atoms fatty acid-carbon/min/30 g body weight, n = 3 to 6 mice/time point/group]. Feeding reduced these rates 90% in control mice and 53% in mice with early tumors, but only 14% in mice with advanced tumors. Plasma FFA fractional catabolic rates were 2.5 times faster in fed mice with advanced tumors than in controls. Diminished suppression of fatty acid mobilization in fed tumor-bearing mice (at night) probably accounts partially for the body fat loss.  相似文献   
152.
Rees and Convit antigens prepared from armadillo-derived Mycobacterium leprae were used for skin testing in two leprosy endemic villages to understand their use in the epidemiology of leprosy. In all, 2602 individuals comprising 202 patients with leprosy detected in a prevalence survey, 476 household contacts and 1924 persons residing in non-case households were tested with two antigens. There was a strong and positive correlation (r = 0.85) between reactions to the Rees and Convit antigens. The distribution of reactions was bimodal and considering reactions of 12 mm or more as 'positive', the positivity rate steeply increased with the increase in age. However, the distributions of reactions to these antigens in patients with leprosy, their household contacts and persons living in non-case households were very similar. These results indicate that Rees and Convit antigens are not useful in the identification of M. leprae infection or in the confirmation of leprosy diagnosis in a leprosy endemic population with a high prevalence of nonspecific sensitivity.  相似文献   
153.

Background  

Little is known about influences on perceptions of neighborhood food environments, despite their relevance for food-shopping behaviors and food choices.  相似文献   
154.

Background

Controlled attenuation parameter (CAP) is a novel, noninvasive technique for assessing hepatic steatosis. However, its role in morbidly obese individuals is unclear. The effect of bariatric surgery on inflammation and fibrosis needs to be explored.

Objectives

To assess the utility of CAP for assessment of hepatic steatosis in morbidly obese individuals and evaluate the effect of bariatric surgery on hepatic steatosis and fibrosis.

Setting

A tertiary care academic hospital.

Methods

Baseline details of anthropometric data, laboratory parameters, FibroScan (XL probe), and liver biopsy were collected. Follow-up liver biopsy was done at 1 year.

Results

Of the 124 patients screened, 76 patients were included; mean body mass index was 45.2 ± 7.1 kg/m2. FibroScan success rate was 87.9%. The median liver stiffness measurement (LSM) and CAP were 7.0 (5.0–9.5) kPa and 326.5 (301–360.5) dB/m, respectively. On liver histopathology, severe steatosis and nonalcoholic steatohepatitis were present in 5.3% and 15.8%; significant fibrosis (≥stage 2) and cirrhosis in 39.5% and 2.6%, respectively. Area under receiver operator characteristic curve of LSM for prediction of significant fibrosis (F2–4 versus F0–1) and advanced fibrosis (F3–4 versus F0–2) was .65 (95% confidence interval [CI]: .52–.77) and .83 (95% CI: .72–.94), respectively. The area under receiver operator characteristic curve of CAP for differentiating moderate hepatic steatosis (S2–3 versus S0–1) and severe hepatic steatosis (S3 versus S0–2) was .74 (95% CI: .62–.86) and .82 (95% CI: .73–.91), respectively. At 1-year follow-up, 32 patients underwent liver biopsy. In these patients, there was significant improvement in hepatic steatosis (P = .001), lobular inflammation (P = .033), ballooning (P<.001), and fibrosis (P = .003). Nonalcoholic steatohepatitis was resolved in 3 of 4 (75%) patients. LSM and CAP significantly declined.

Conclusions

LSM and CAP are feasible and accurate at diagnosing advanced fibrosis and severe hepatic steatosis in morbidly obese individuals. Bariatric surgery is associated with significant improvement in LSM, CAP, steatohepatitis, and fibrosis.  相似文献   
155.
To evaluate the role of oral ketamine as an adjuvant to oral morphine in cancer patients experiencing neuropathic pain, 9 cancer patients (5 men, 4 women) taking maximally tolerated doses of either morphine, amitriptyline, sodium valproate, or a combination of these drugs for intractable neuropathic pain, and reporting a pain score of >6 on a 0-10 scale, were studied prospectively to evaluate analgesia and adverse effects. Ketamine in the dose of 0.5 mg/kg body weight three times daily was added to the existing drug regimen. Patients were taught to maintain a pain diary wherein they daily recorded their pain, sedation, and vomiting scores, and other side effects. A decrease of more than 3 from the baseline in the average pain score, or a score of < or =3 was taken as a successful response. Seven patients exhibited a decrease of more than 3. Four patients experienced nausea, of which one had vomiting. Two developed loss of appetite. Eight patients reported drowsiness during the first two weeks of therapy (P = 0.001), and this gradually improved over the next two weeks in 5 of these 8 patients. Three patients withdrew from the study, two owing to excessive sedation and another due to a "feeling of unreality." None of the patients reported visual or auditory hallucinations. This experience suggests that low dose oral ketamine is beneficial and effective in the management of intractable neuropathic pain in patients with advanced cancer. However, its utility is limited in some patients by the adverse effects that accompany its use.  相似文献   
156.
157.
BACKGROUND: Platelets become activated during storage, which results in secretion of granules, vesiculation of microparticles, secretion of protein, and a number of other biochemical and morphologic processes that decrease the utility of platelet concentrates stored for transfusion. STUDY DESIGN AND METHODS: To evaluate the quality of stored platelet concentrates, the cell surface expression of specific activation-dependent antigens (CD62 and lysosome-associated membrane proteins 1 and 2 [LAMP-1, LAMP-2]) on platelets stored in a hospital blood bank over a 7-day period was examined. Relative microparticle counts and the expression of CD62 by microparticles, as well as platelet concentrate supernatant levels of soluble CD62, were determined. RESULTS: The percentage of platelets expressing CD62 increased significantly from Day 1 to Day 5 (p < 0.05) of storage; the mean fluorescence values for CD62 did not. In contrast, the mean fluorescence values of LAMP-1 and LAMP-2 rose significantly (p < 0.01 and p < 0.05, respectively) between Days 1 and 5. Significant declines in CD62, LAMP-1, and LAMP-2 percent expression and mean fluorescence were seen on Day 6 of storage (p < 0.001). Microparticle numbers increased significantly during storage and correlated with levels of CD62 protein (free and membrane-bound) (r = 0.95 vs. Day 2, p < 0.05; r = 0.88 vs. Day 5, p < 0.05). CONCLUSION: Flow cytometric evaluations of the expression of cell surface CD62, LAMP-1, and LAMP-2 are complementary tests that, especially when used in conjunction with the quantitation of CD62 protein, provided a simple and effective means of evaluating the quality of platelet concentrates stored for transfusion.  相似文献   
158.
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160.
Our understanding of dose-related effects of polymeric black tea polyphenols (PBPs), the most abundant polyphenols in black tea, is limited. In the present study, the effect of various doses of black tea (0.75, 1.5, and 3%)-derived PBP-rich extract on biochemical parameters and lung carcinogenicity in A/J mice was investigated. Pretreatment with PBPs showed the dose-related decrease in B(a)P-induced expression and activity of CYP1A1 in the liver while CYP1A2 expression and activity in the lung. Dose-dependent significant increase in PBP-mediated over-expression and activity of GSTs (alpha in the liver while pi in the lung) were observed in polyphenol-treated groups. Significant dose-related decrease in number and intensity of BPDE-DNA adducts were observed in liver and lung. Black tea (1.5%, 3%)-derived PBPs showed dose-mediated decrease in lung tumor incidence and multiplicity which was further correlated with different molecular markers like cell proliferation and apoptosis in B(a)P and NNK model. In conclusion, dose-dependent chemopreventive effects of PBPs, both anti-initiating (induction of phase II and inhibition of carcinogen-induced phase-I enzymes leading to decrease in BPDE-DNA adducts) and anti-promoting (decreased cell proliferation and increased apoptosis lowering incidence and/or multiplicity of lung lesions), were observed in A/J mice without significant toxicity.  相似文献   
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