The incidence of vasculitis is increased in female stroke-prone hypertensive rats compared to males

Background: Vascular changes in hypertension share common characteristics with inflammatory wall injury. Since it is known that chronic inflammatory diseases are frequently more prevalent in females, this study tested the hypothesis that vasculitis would be more evident in female stroke-prone spontaneously hypertensive rats (SHRSP) than in males.Methods: Arterial lesions were characterized in the gastrointestinal tract of necropsied SHRSP and normotensive Wistar-Kyoto rats (WKY). Systolic blood pressure was measured using the tail cuff method.Results: Vasculitis was present in 54% of SHRSP (n=357). None of the WKY rats had the vascular disease (n=373). Arterial lesions were not evident in young SHRSP (1-1.5 months of age) before the development of high blood pressure. The earliest appearance of vasculitis in SHRSP was at ~8 months of age after full establishment of elevated arterial pressure. Systolic blood pressures during the maintained phase were greater than 200mmHg for SHRSP and less than 130mmHg for WKY rats (ages: 8-18 months). Within SHRSP, lesions were more common in females, in spite of higher mean systolic pressure found in males (both p<0.05). Of the female SHRSP, 70% (n=234) had severe micronodular vasculitis whereas 24% of male SHRSP showed lesions (age matched).Conclusion: These observations indicate that in SHRSP: 1) inflammatory responses in arteries occur with greater incidence compared to WKY rats; 2) there is a relationship between incidence of vascular lesions and age, but not elevated arterial pressure; and 3) there is a higher incidence of vasculitic lesions in females compared to males.Keywords: Vasculitis, Stroke-prone, SHR, WKY, Blood pressure, Hypertensio

Salsalate treatment improves glycemia without altering adipose tissue in nondiabetic obese hispanics.

ObjectiveSalsalate treatment has well-known effects on improving glycemia, and the objective of this study was to examine whether the mechanism of this effect was related to changes in adipose tissue.MethodsA randomized double-blind and placebo-controlled trial in obese Hispanics (18-35 years) was conducted. The intervention consisted of 4 g day(-1) of salsalate (n = 11) versus placebo (n = 13) for 4 weeks. Outcome measures included glycemia, adiposity, ectopic fat, and adipose tissue gene expression and inflammation.ResultsIn those receiving salsalate, plasma fasting glucose decreased by 3.4% (P < 0.01), free fatty acids decreased by 42.5% (P = 0.06), and adiponectin increased by 27.7% (P < 0.01). Salsalate increased insulin AUC by 38% (P = 0.01) and HOMA-B by 47.2% (P < 0.01) while estimates of insulin sensitivity/resistance were unaffected. These metabolic improvements occurred without changes in total, abdominal, visceral, or liver fat. Plasma markers of inflammation/immune activation were unchanged following salsalate. Salsalate had no effects on adipose tissue including adipocyte size, presence of crown-like structures, or gene expression of adipokines, immune cell markers, or cytokines downstream of NF-κB with the exception of downregulation of IL-1β (P < 0.01).ConclusionsFindings suggest that metabolic improvements in response to salsalate occurred without alterations in adiposity, ectopic fat, or adipose tissue gene expression and inflammation

Consistency of the Disposition Index in the Face of Diet Induced Insulin Resistance: Potential Role of FFA

Objective Insulin resistance induces hyperinsulinemic compensation, which in turn maintains almost a constant disposition index. However, the signal that gives rise to the hyperinsulinemic compensation for insulin resistance remains unknown. Methods In a dog model of obesity we examined the possibility that potential early-week changes in plasma FFA, glucose, or both could be part of a cascade of signals that lead to compensatory hyperinsulinemia induced by insulin resistance. Results Hypercaloric high fat feeding in dogs resulted in modest weight gain, and an increase in adipose tissue with no change in the non-adipose tissue size. To compensate for the drop in insulin sensitivity, there was a significant rise in plasma insulin, which can be attributed in part to a decrease in the metabolic clearance rate of insulin and increased insulin secretion. In this study we observed complete compensation for high fat diet induced insulin resistance as measured by the disposition index. The compensatory hyperinsulinemia was coupled with significant changes in plasma FFAs and no change in plasma glucose. Conclusions We postulate that early in the development of diet induced insulin resistance, a change in plasma FFAs may directly, through signaling at the level of β-cell, or indirectly, by decreasing hepatic insulin clearance, result in the observed hyperinsulinemic compensation

Ninth and Tenth Order Virial Coefficients for Hard Spheres in D Dimensions

We evaluate the virial coefficients B_k for k<=10 for hard spheres in dimensions D=2,...,8. Virial coefficients with k even are found to be negative when D>=5. This provides strong evidence that the leading singularity for the virial series lies away from the positive real axis when D>=5. Further analysis provides evidence that negative virial coefficients will be seen for some k>10 for D=4, and there is a distinct possibility that negative virial coefficients will also eventually occur for D=3.Comment: 33 pages, 12 figure

Sources and cycling of dissolved and particulate organic radiocarbon in the northwest Atlantic continental margin

Continental shelves and slopes are productive and dynamic ocean margin systems that also regulate the fluxes of terrestrial, riverine, and estuarine materials between the continents and oceans. In order to evaluate the ages, potential sources, and transformations of organic matter in an ocean margin system, we measured the radiocarbon (Delta (14)C and delta (13)C distributions of total dissolved organic carbon (DOC), suspended particulate organic carbon (POC), and dissolved inorganic carbon (DIC) in waters of the Middle Atlantic Bight (MAB) continental shelf and slope in April-May 1994. The Delta (14)C of DOC was greatest (as high as -39 parts per thousand) in surface waters of the shelf, decreasing rapidly offshore and with depth, even in relatively shallow (25-50 in depth) shelf waters. The lowest Delta (14)C-DOC values were observed in deep slope waters, where they were significantly lower than values measured previously for the deep Sargasso Sea. There was a strong inverse relationship between Delta (14)C-DOC and delta (-13)C-DOC in all shelf and surface slope waters of the MAB, which is likely attributable to varying contributions of young, (14)C-enriched organic matter of terrestrial and/or riverine origin. The more highly (14)C-depleted DOC in deep : slope waters (as low as -442 parts per thousand) generally had a correspondingly lower delta (13)C (as low as -22.3 parts per thousand) component. However, this must originate from relic terrestrial material either in the MAB itself or be discharged to the MAB from rivers and estuaries. The isotopic signatures of POC were clearly differentiable from DOC and indicate that this pool also contained a broad range of both old and young material of terrestrial (delta (13)C as low as -24.9 parts per thousand) and marine (delta (13)C as high as -19.9 parts per thousand) origin throughout the MAB shelf and slope. The highest Delta (14)C-POC values (up to 78 parts per thousand) were observed in shallow shelf waters of the southern MAR Conversely, the lowest Delta (14)C-POC values (as low as -394 parts per thousand) were found in MAB deep slope waters and were also significantly more depleted in (14)C than POC from the central north Atlantic (Sargasso Sea). A multiple-source isotopic mass balance model employing both (14)C and (13)C was used to evaluate the relative contributions of both young and old terrigenous versus marine organic matter to DOC and POC in the MAR The results indicate that shelf and slope DOC is comprised of an old marine fraction (represented by offshore Sargasso Sea material) and either a young terrestrial/riverine/estuarine (TRE) component (in shelf and shallow slope waters) or a relic TRE component (in deep and some shallow slope waters). In contrast, suspended POC from the MAB appears to originate predominantly from a mixture of recent MAB primary production and an old, TRE component, similar to that observed in one of the major subestuaries of the Chesapeake Bay. These results suggest that both young and old sources of terrestrial and riverine organic matter can comprise a significant fraction of the DOC and POC in ocean margins. Preliminary calculations indicate that the export of this compositionally unique DOC and suspended POC may be significant terms in the organic carbon budgets of the MAB and other margin systems

Salsalate treatment improves glycemia without altering adipose tissue in nondiabetic obese hispanics.

ObjectiveSalsalate treatment has well-known effects on improving glycemia, and the objective of this study was to examine whether the mechanism of this effect was related to changes in adipose tissue.MethodsA randomized double-blind and placebo-controlled trial in obese Hispanics (18-35 years) was conducted. The intervention consisted of 4 g day(-1) of salsalate (n = 11) versus placebo (n = 13) for 4 weeks. Outcome measures included glycemia, adiposity, ectopic fat, and adipose tissue gene expression and inflammation.ResultsIn those receiving salsalate, plasma fasting glucose decreased by 3.4% (P &lt; 0.01), free fatty acids decreased by 42.5% (P = 0.06), and adiponectin increased by 27.7% (P &lt; 0.01). Salsalate increased insulin AUC by 38% (P = 0.01) and HOMA-B by 47.2% (P &lt; 0.01) while estimates of insulin sensitivity/resistance were unaffected. These metabolic improvements occurred without changes in total, abdominal, visceral, or liver fat. Plasma markers of inflammation/immune activation were unchanged following salsalate. Salsalate had no effects on adipose tissue including adipocyte size, presence of crown-like structures, or gene expression of adipokines, immune cell markers, or cytokines downstream of NF-κB with the exception of downregulation of IL-1β (P &lt; 0.01).ConclusionsFindings suggest that metabolic improvements in response to salsalate occurred without alterations in adiposity, ectopic fat, or adipose tissue gene expression and inflammation

Consistency of the hyperbolic relationship (DI) between insulin sensitivity and insulin secretion.

<p>Solid black hyperbolic curve =  average DI value for week 0; black solid square  =  average DI for week 0; open square  =  average DI for week 2; black solid triangle  =  average DI for week 4; open triangle  =  average DI for week 6. The hyperbola represents the curve on which the animals would have to remain to maintain a constant DI (DI = AIRg.SI = constant) and it is calculated as extrapolation of the average DI for week 0 over a range of insulin sensitivities.</p

Weekly changes in body weight and body composition.

<p>(A) Body weight increased by week 2 and remained elevated throughout the six-week hypercaloric high-fat feeding period. (B) Visceral (white bar) and subcutaneous (black bar) adipose tissue calculated as area percent of total tissue. *P<.05 vs. week0; **P<.01 vs. week 0; ***P<.001 vs. week 0.</p