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1.

Background Context

Low back pain (LBP) is a common complaint in clinical practice of multifactorial origin. Although obesity has been thought to contribute to LBP primarily by altering the distribution of mechanical loads on the spine, the additional contribution of obesity-related conditions such as diabetes mellitus (DM) to LBP has not been thoroughly examined.

Purpose

To determine if there is a relationship between DM and LBP that is independent of body mass index (BMI) in a large cohort of adult survey participants.

Study Design

Retrospective analysis of prospectively collected National Health and Nutrition Examination Survey (NHANES) data to characterize associations between LBP, DM, and BMI in adults subdivided into 6 subpopulations: normal weight (BMI 18.5–25), overweight (BMI 25–30), and obese (BMI >30) diabetics and nondiabetics. Diabetes was defined with glycohemoglobin A1c (HbA1c) 6.5%.

Patient Sample

11,756 participants from NHANES cohort.

Outcome Measures

Percentage of LBP reported.

Methods

LBP reported in the 1999-2004 miscellaneous pain NHANES questionnaire was the dependent variable examined. Covariates included HbA1c, BMI, age, and family income ratio to poverty as continuous variables as well as race, gender, and smoking as binary variables. Individuals were further subdivided by weight class and diabetes status. Regression and graphical analyses were performed on the study population as a whole and also on subpopulations.

Results

Increasing HbA1c did not increase the odds of reporting LBP in the full cohort. However, multivariate logistic regression of the 6 subpopulations revealed that the odds of LBP significantly increased with increasing HbA1c levels in normal weight diabetics. No other subpopulations reported significant relationships between LBP and HbA1c. LBP was also significantly associated with BMI for normal weight diabetics and also for obese subjects regardless of their DM status.

Conclusions

LBP is significantly related to DM status, but this relationship is complex and may interact with BMI. These results support the concept that LBP may be improved in normal weight diabetic subjects with improved glycemic control and weight loss, and that all obese LBP subjects may benefit from improved weight loss alone.  相似文献   
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Gallstones are common and their incidence increases with age.1 Fifty per cent of these stones are in the common bile duct (CBD) in the elderly.2 Most of them are silent but with time there is an increasing chance of developing symptoms which are more likely to be serious in the elderly.3 Failure to relieve mechanical obstruction of bile flow may lead to secondary biliary cirrhosis.4 It has been estimated that on average secondary biliary cirrhosis develops some seven years after the onset of obstruction from a stricture, four and half years after gallstone obstruction and 10 months after the onset of malignant stricture.5 The characteristic features are the pathological findings of portal-portal linkages, with a pattern of monolobular cirrhosis and the preservation of normal vascular relationships.6 Secondary biliary cirrhosis may lead to hepatic insufficiency and portal hypertension with the resultant complications, such as bleeding oesophageal varices, hypersplenism with pancytopenia, ascites and encephalopathy. We describe a patient in whom the diagnosis was not suspected until laparotomy and confirmed only at autopsy.  相似文献   
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The expression of alpha melanocyte stimulating hormone (MSH) has been investigated in two variants of the B16 murine melanoma. The presence of MSH was demonstrated by immunohistochemical methods using anti-MSH antibodies. The low metastasis variant B16-F1, which grows as an encapsulated non-invasive tumour, showed no alpha-MSH immunoreactivity. In contrast, the high metastasis variant BL6 was found to be alpha-MSH positive and the immunoreactivity was found predominantly in the peripheral invading zones of the tumour.  相似文献   
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In the brain, nitric oxide (NO) has been identified as a messenger molecule and a mediator of excitatory amino acid-induced neurotoxicity. In this study, the effects of NO on serum-induced mitogenesis and cell proliferation of the cerebellar glial cells were assessed. NO-generating agent, S-nitroso-N-acetylpenicillamine (SNAP) increased intracellular cyclic guanosine monophosphate (cGMP) levels. Furthermore, 2 chemically dissimilar NO-generating agents, SNAP and sodium nitroprusside (SNP) inhibited serum-induced thymidine incorporation and cell proliferation. The antimitogenic effect of NO was mimicked by 8-bromo-cGMP and blocked by hemoglobin, a known inhibitor of NO. The effect of NO was not cytotoxic, since the cells were not stained with Trypan blue and did not show increased release of lactate dehydrogenase in the culture supernatants. However, NO-treated cells showed decreased conversion of tetrazolium to blue formazan suggesting that NO inhibited mitochondrial activity in the glial cells. These results demonstrate that NO inhibits serum-induced mitogenesis and cell proliferation of cultured rat cerebellar glial cells.  相似文献   
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Summary The pharmacokinetics of total radioactivity and unchanged drug were studied in patients receiving Anandron (Nilutamide, RU 23908) after a single dose of [14C] Anandron and after q12 h dosings of unlabelled drug for 2–7 weeks. The results indicate that the radioactivity in plasma consists of unchanged drug and metabolites. The plasma decay of Anandron after the absorption phase was biexponential in all patients, with the terminal phase half-life ranging from 23.3–87.2 h. The plasma decay of total radioactivity after the absorption phase was biexponential in 3/12 and monoexponential in 9/12 patients. The calculated terminal phase half-lives for total radioactivity after [14C] Anandron were 34.5–137.3 h. The AUC0– of the unchanged drug in plasma represented 23%–38% of the AUC0– of total radioactivity. Urinary radioactivity consisted primarily of metabolites, the majority of which were chloroform-nonextractable. Urinary excretion of radioactivity at 120 h ranged from 49%–78% of the administered dose; the unchanged Anandron (at 72 h) was 0.6%–1.3% of the dose. In three patients studied, the fecal excretion of Anandron was 1.4%–7.0%. Steady-state plasma levels (4.4–8.5 g/ml) were attained within approximately 2 weeks from the initiation of twice daily dosing of Anandron. When the plasma pharmacokinetics of radioactivity and unchanged drug after the first single dose were compared with that during steady state, AUC0–12 h of unchanged Anandron during steady state was significantly higher than the AUC0– after the first single dose, suggesting that the plasma clearance of Anandron is lowered upon chronic administration of the drug, assuming that the bioavailability is constant.  相似文献   
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Eighty-five young Mauritian Indians, male survivors of premature myocardial infarction (MI) and thus belonging to a high risk group, were compared with 108 stringently selected controls for a possible association between premature MI and an insertion/deletion (I/D) polymorphism in the gene encoding angiotensin I-converting enzyme (ACE). The frequency of the D allele was 0.42 in the MI group and 0.43 in the control group, and thus no association between I/D polymorphism of ACE with susceptibility to early-onset MI was found in this population group. Other gene components of the renin-angiotensin system and lipid metabolism need to be explored to understand the genetic factors involved in causing MI at an early age.  相似文献   
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