We studied the effects of exercise training in patients with chronic heart failure attributed to left ventricular dysfunction (ejection fraction, 24 +/- <em>1</em>0%). Twelve ambulatory patients with stable symptoms underwent 4-6 months of conditioning by exercising 4.<em>1</em> +/- 0.6 hr/wk at a heart rate corresponding to 75% of peak oxygen consumption. Before and after training, patients underwent maximal bicycle exercise testing with direct measurement of central hemodynamic, leg blood flow, and metabolic responses. Exercise training resulted in a decrease in heart rate at rest and submaximal exercise and a 23% increase in peak oxygen consumption from <em>1</em>6.8 +/- 3.8 to 20.6 +/- 4.7 <em>ml</em>/kg/min (p less than 0.0<em>1</em>). Heart rate, arterial lactate, and respiratory exchange ratio were unchanged at peak exercise after training. Maximal cardiac output tended to increase from 8.9 +/- 2.7 to 9.9 +/- 3.2 <em>1</em>/min and contributed to improved peak oxygen consumption in some patients, although this change did not reach statistical significance (p = 0.<em>1</em>3). Rest and exercise measurements of left ventricular ejection fraction, left ventricular end-diastolic volume, and left ventricular end-systolic volume were unchanged. Right atrial, pulmonary arterial, pulmonary capillary wedge, and systemic arterial pressures were not different after training. Training induced several important peripheral adaptations that contributed to improved exercise performance. At peak exercise, systemic arteriovenous oxygen difference increased from <em>1</em>3.<em>1</em> +/- <em>1</em>.4 to <em>1</em>4.6 +/- 2.3 <em>ml</em>/dl (p less than 0.05). This increase was associated with an increase in peak-exercise leg blood flow from 2.5 +/- 0.7 to 3.0 +/- 0.8 l/min (p less than 0.0<em>1</em>) and an increase in leg arteriovenous oxygen difference from <em>1</em>4.5 +/- <em>1</em>.3 to <em>1</em>6.<em>1</em> +/- <em>1</em>.9 <em>ml</em>/dl (p = 0.07). Arterial and femoral venous lactate levels were markedly reduced during submaximal exercise after training, even though cardiac output and leg blood flow were unchanged at these workloads. Thus, ambulatory patients with chronic heart failure can achieve a significant training effect from long-term exercise. Peripheral adaptations, including an increase in peak blood flow to the exercising leg, played an important role in improving exercise tolerance.(ABSTRACT TRUNCATED AT 400 WORDS)

OBJECTIVE

An emerging model of metabolic syndrome and type 2 diabetes is of adipose dysfunction with leukocyte recruitment into adipose leading to chronic inflammation and insulin resistance (IR). This study sought to explore potential mechanisms of inflammatory-induced IR in humans with a focus on adipose tissue.

METHODS

We performed a 60-h endotoxemia protocol (3 ng/kg intravenous bolus) in healthy adults (n = 20, 50% male, 80% Caucasian, aged 27.3 +/- 4.8 years). Before and after endotoxin, whole-blood sampling, subcutaneous adipose biopsies, and frequently sampled intravenous glucose tolerance (FSIGT) testing were performed. The primary outcome was the FSIGT insulin sensitivity index (S(i)). Secondary measures included inflammatory and metabolic markers and whole-blood and adipose mRNA and protein expression.

RESULTS

Endotoxemia induced systemic IR as demonstrated by a 35% decrease in S(i) (3.<em>1</em>7 +/- <em>1</em>.66 to 2.06 +/- 0.73 x <em>1</em>0(-4) [microU * <em>ml</em>(-<em>1</em>) * min(-<em>1</em>)], P < 0.005), while there was no effect on pancreatic beta-cell function. In adipose, endotoxemia suppressed insulin receptor substrate-<em>1</em> and markedly induced suppressor of cytokine signaling proteins (<em>1</em> and 3) coincident with local activation of innate (interleukin-6, tumor necrosis factor) and adaptive (monocyte chemoattractant protein-<em>1</em> and CXCL<em>1</em>0 chemokines) inflammation. These changes are known to attenuate insulin receptor signaling in model systems.

CONCLUSIONS

We demonstrate, for the first time in humans, that acute inflammation induces systemic IR following modulation of specific adipose inflammatory and insulin signaling pathways. It also provides a rationale for focused mechanistic studies and a model for human proof-of-concept trials of novel therapeutics targeting adipose inflammation in IR and related consequences in humans.

BACKGROUND

Overweight and obesity are well-established risk factors for cardiovascular disease and decline in kidney function in individuals with existing chronic kidney disease (CKD). Conversely, their association with the development of CKD is less clear.

METHODS

We evaluated the association between body mass index (BMI) and risk for CKD in a cohort of <em>1</em><em>1</em>,<em>1</em>04 initially healthy men who participated in the Physicians' Health Study and provided a blood sample after <em>1</em>4 years. BMI was calculated from self-reported weight and height. We estimated glomerular filtration rate (GFR) by using the abbreviated equation from the Modification of Diet in Renal Disease Study and defined CKD as GFR less than 60 <em>mL</em>/min/<em>1</em>.73 m2 ((<em>1</em> <em>mL</em>/s/<em>1</em>.73 m2).

RESULTS

After an average <em>1</em>4-year follow-up, <em>1</em>,377 participants (<em>1</em>2.4%) had a GFR less than 60 <em>mL</em>/min/<em>1</em>.73 m2 ((<em>1</em> <em>mL</em>/s/<em>1</em>.73 m2). Higher baseline BMI was associated consistently with increased risk for CKD. Compared with participants in the lowest BMI quintile (<22.7 kg/m2), those in the highest quintile (>26.6 kg/m2) had an odds ratio (OR) of <em>1</em>.45 (95% confidence interval [CI], <em>1</em>.<em>1</em>9 to <em>1</em>.76; P trend <0.00<em>1</em>) after adjusting for potential confounders. We found similar associations by using different categories of BMI. Compared with men who remained within a +/-5% range of their baseline BMI, those who reported a BMI increase greater than <em>1</em>0% had a significant increase in risk for CKD (OR, <em>1</em>.27; 95% CI, <em>1</em>.06 to <em>1</em>.53).

CONCLUSIONS

In this large cohort of initially healthy men, BMI was associated significantly with increased risk for CKD after <em>1</em>4 years. Strategies to decrease CKD risk might include prevention of overweight and obesity.

There exists a unique group of persons who are able to durably control HIV in the absence of therapy. The mechanisms of control in these persons remain poorly defined. In this study, we examined CD8(+) T-cell responses in blood and rectal mucosa from <em>1</em>7 "elite controllers" (viral load < 75 copies/<em>mL</em>), <em>1</em><em>1</em> "viremic controllers" (75-2000 copies/<em>mL</em>), <em>1</em>4 noncontrollers >> <em>1</em>0,000 copies/<em>mL</em>), and <em>1</em>0 antiretroviral-treated persons (< 75 copies/<em>mL</em>). Production of interferon-gamma, interleukin-2, tumor necrosis factor-alpha, macrophage inflammatory protein-<em>1</em> beta, and CD<em>1</em>07a by CD8(+) T cells in response to HIV-<em>1</em> Gag stimulation was measured using flow cytometry. Our hypothesis was that "polyfunctional" T cells producing multiple antiviral factors would be most abundant in mucosal tissues of HIV controllers. Mucosal CD8(+) T-cell responses were significantly stronger and more complex in controllers than in antiretroviral-suppressed persons (P = .0004). The frequency of 4-function responses in rectal mucosa was higher in controllers than in noncontrollers and patients on therapy (P < .000<em>1</em>). Mucosal responses in controllers were frequently stronger and more complex than blood responses. These findings demonstrate that many controllers mount strong, complex HIV-specific T-cell responses in rectal mucosa. These responses may play an important role in mucosal immune surveillance, as suggested by their relative enrichment among persons who control HIV in the absence of therapy.

Twenty-eight human isolates of Escherichia coli from Argentina and Spain and eight veterinary isolates received from the Ministry of Agriculture Fisheries and Foods in the United Kingdom required 2 to>> <em>1</em>28 micrograms of ciprofloxacin per <em>ml</em> for inhibition. Fragments of gyrA and parC encompassing the quinolone resistance-determining region were amplified by PCR, and the DNA sequences of the fragments were determined. All isolates contained a mutation in gyrA of a serine at position 83 (Ser83) to an Leu, and 26 isolates also contained a mutation of Asp87 to one of four amino acids: Asn (n = <em>1</em>4), Tyr (n = 6), Gly (n = 5), or His (n = <em>1</em>). Twenty-four isolates contained a single mutation in parC, either a Ser80 to Ile (n = <em>1</em>7) or Arg (n = 2) or a Glu84 to Lys (n = 3). The role of a mutation in gyrB was investigated by introducing wild-type gyrB (pBP548) into all isolates; for three transformants MICs of ciprofloxacin were reduced; however, sequencing of PCR-derived fragments containing the gyrB quinolone resistance-determining region revealed no changes. The analogous region of parE was analyzed in 34 of 36 isolates by single-strand conformational polymorphism analysis and sequencing; however, no amino acid substitutions were discovered. The outer membrane protein and lipopolysaccharide profiles of all isolates were compared with those of reference strains, and the concentration of ciprofloxacin accumulated (with or without <em>1</em>00 microM carbony cyanide m-chlorophenylhydrazone [CCCP] was determined. Twenty-two isolates accumulated significantly lower concentrations of ciprofloxacin than the wild-type E. coli isolate; nine isolates accumulated less then half the concentration. The addition of CCCP increased the concentration of ciprofloxacin accumulated, and in all but one isolate the percent increase was greater than that in the control strains. The data indicate that high-level fluoroquinolone resistance in E. coli involves the acquisition of mutations at multiple loci.

Muscle glycogen stores are depleted during exercise and are rapidly repleted during the recovery period. To investigate the mechanism for this phenomenon, untrained male rats were run for 45 min on a motor-driven treadmill and the ability of their muscles to utilize glucose was then assessed during perfusion of their isolated hindquarters. Glucose utilization by the hindquarter was the same in exercised and control rats perfused in the absence of added insulin; however, when insulin (30-40,000 muU/<em>ml</em>) was added to the perfusate, glucose utilization was greater after exercise. Prior exercise lowered both, the concentration of insulin that half-maximally stimulated glucose utilization (exercise, <em>1</em>50 muU/<em>ml</em>; control, 480 muU/<em>ml</em>) and modestly increased its maximum effect. The increase in insulin sensitivity persisted for 4 h following exercise, but was not present after 24 h. The rate-limiting step in glucose utilization enhanced by prior exercise appeared to be glucose transport across the cell membrane, as in neither control nor exercised rats did free glucose accumulate in the muscle cell. Following exercise, the ability of insulin to stimulate the release of lactate into the perfusate was unaltered; however its ability to stimulate the incorporation of [(<em>1</em>4)C]glucose into glycogen in certain muscles was enhanced. Thus at a concentration of 75 muU/<em>ml</em> insulin stimulated glycogen synthesis eightfold more in the fast-twitch red fibers of the red gastrocnemius than it did in the same muscle of nonexercised rats. In contrast, insulin only minimally increased glycogen synthesis in the fast-twitch white fibers of the gastrocnemius, which were not glycogen-depleted. The uptake of 2-deoxyglucose by these muscles followed a similar pattern suggesting that glucose transport was also differentially enhanced. Prior exercise did not enhance the ability of insulin to convert glycogen synthase from its glucose-6-phosphate-dependent (D) to its glucose-6-phosphate-independent (<em>1</em>) form. On the other hand, following exercise, insulin prevented a marked decrease in muscle glucose-6-phosphate, which could have diminished synthase activity in situ. The possibility that exercise enhanced the ability of insulin to convert glycogen synthase D to an intermediate form of the enzyme, more sensitive to glucose-6-phosphate, remains to be explored. These results suggest that following exercise, glucose transport and glycogen synthesis in skeletal muscle are enhanced due at least in part to an increase in insulin sensitivity. They also suggest that this increase in insulin sensitivity occurs predominantly in muscle fibers that are deglycogenated during exercise.

The metabolism of low density lipoprotein (LDL, beta lipoprotein) was studied in <em>1</em>0 normal individuals and <em>1</em>0 patients with familial type II hyperlipoproteinemia using purified radioiodinated LDL. Over 97% of the label was bound to the protein moiety of LDL and therefore the turnover data reflect the fate and distribution of LDL-apoprotein. Comparison of the metabolic behavior of biologically screened and unscreened labeled LDL preparations in dogs as well as the analysis of the urinary excretion of radioiodide derived from labeled LDL degradation in humans indicated that no significant denaturation resulted from the isolation, purification, and labeling techniques. The plasma concentration of LDL-cholesterol in normals was <em>1</em>05+/-2<em>1</em> mg/<em>1</em>00 <em>ml</em> (mean +/-<em>1</em> SD) in contrast to 254+/-47 mg/<em>1</em>00 mg in patients with type II hyperlipoproteinemia; these values corresponded to LDL-apoprotein concentrations of 63+/-<em>1</em>3 mg/<em>1</em>00 <em>ml</em> and <em>1</em>53+/-30 mg/<em>1</em>00 <em>ml</em>, respectively. Despite these differences in concentration, the synthetic rate of LDL-apoprotein in both groups was not significantly different (<em>1</em>4.43+/-<em>1</em>.75 mg/kg per day in normals vs. <em>1</em>5.0<em>1</em>+/-<em>1</em>.7<em>1</em> mg/kg per day in type II) nor was there any difference in the fraction of the total exchangeable LDL which was in the intravascular space (68.4+/-4.3% vs. 73.3+/-5.2%). However, the fractional catabolic rate of LDL in normal individuals differed significantly from that of patients with type II hyperlipoproteinemia (0.462+/-0.077/day in normals vs. 0.237+/-0.044/day in type II) and correspondingly the biological half-life of LDL was significantly prolonged (3.08+/-0.35 days normals vs. 4.68+/-0.44 days in type II). These data indicate that the pathologic elevation of plasma LDL concentration in the individuals with type II hyperlipoproteinemia studied here is due to a decreased fractional rate of LDL degradation rather than to an abnormality of LDL synthesis. This defect of catabolism may be the primary defect in type II hyperlipoproteinemia or, alternatively, may be secondary to an underlying abnormality in lipid metabolism.

BACKGROUND

It is commonly stated in the literature on human exposure to bisphenol A (BPA) that food is the predominant BPA exposure source, and that BPA is rapidly and completely cleared from the body. If this is correct, BPA levels in fasting individuals should decrease with increased fasting time.

OBJECTIVE

We set out to investigate the relationship between urine BPA concentration and fasting time in a population-based sample.

METHODS

We modeled log BPA urine concentration as a function of fasting time, adjusted for urine creatinine and other confounders, in <em>1</em>,469 adult participants in the 2003-2004 National Health and Nutrition Examination Survey. We estimated the BPA "population-based half-life" (pop(<em>1</em>/2)) for a fasting time of 0-24 hr, < 4.5 hr, 4.5-8.5 hr, and>> 8.5 hr.

RESULTS

The overall pop(<em>1</em>/2) for the 0- to 24-hr interval was 43 hr [95% confidence interval (CI), 26-<em>1</em><em>1</em>9 hr]. Among those reporting fasting times of 4.5-8.5 hr (n = 44<em>1</em>), BPA declined significantly with fasting time, with a pop(<em>1</em>/2) of 4.<em>1</em> hr (95% CI, 2.6-<em>1</em>0.6 hr). However, within the fasting time intervals of 0-4.5 hr (n = <em>1</em>29) and 8.5-24 hr (n = 899), we saw no appreciable decline. Fasting time did not significantly predict highest >> <em>1</em>2 ng/mL) or lowest (below limit of detection) BPA levels.

CONCLUSIONS

Overall, BPA levels did not decline rapidly with fasting time in this sample. This suggests substantial nonfood exposure, accumulation in body tissues such as fat, or both. Explaining these findings may require experimental pharmacokinetic studies of chronic BPA exposure, further examination of BPA levels and effects in fat, and a search for important nonfood sources.

OBJECTIVE

To evaluate the diagnostic sensitivity of antibodies to cyclic citrullinated peptide (CCP) in recent onset rheumatoid arthritis (RA) at diagnosis and 3 years later, and to evaluate anti-CCP antibody as a predictor of the disease course during 3 years.

METHODS

242 patients with recent onset (< or =<em>1</em> year) RA were followed up regularly during 3 years after inclusion in the Swedish multicentre study "TIRA" <em>1</em>996-98. Anti-CCP antibodies were analysed by an enzyme immunoassay (EIA). Rheumatoid factors (RFs) were analysed by latex agglutination and two isotype-specific (IgM and IgA) EIAs. Disease activity was assessed by plasma CRP, ESR, 28 joint disease activity score, and the physician's global assessment of disease activity. Functional ability was evaluated by the Health Assessment Questionnaire.

RESULTS

Overall, the diagnostic sensitivity of anti-CCP antibodies was 64% and the proportion of positive tests increased with the number of fulfilled classification criteria according to the American College of Rheumatology. The anti-CCP antibody results correlated with RF, but were better than RF as predictor of a more aggressive disease course. After 3 years 5/97 patients had changed anti-CCP status: 2 from negative to positive and 3 from positive to negative. The mean level of anti-CCP antibodies declined by <em>1</em>3<em>1</em> U/ml during the 3 year follow up (95% CI 34 to 228 U/ml).

CONCLUSIONS

The anti-CCP antibody assay has a similar diagnostic sensitivity to that of RF in early RA, but is better as a predictor of the disease course over 3 years. Although the mean serum level declines, anti-CCP antibody positivity remains essentially unaltered 3 years after diagnosis and start of antirheumatic treatment.

The dengue (DEN) viruses are positive-strand RNA viruses in the genus Flavivirus. Dengue fever and dengue hemorrhagic fever/dengue shock syndrome are important human arboviral diseases caused by infection with one of four closely related but serologically distinct DEN viruses, designated DEN-<em>1</em>, DEN-2, DEN-3, and DEN-4 viruses. All four DEN serotypes are currently co-circulating throughout the subtropics and tropics, and genotypic variation occurs among isolates within a serotype. A real-time quantitative nucleic acid amplification assay has been developed to detect viral RNA of a single DEN virus serotype. Each primer-probe set is DEN serotype specific, yet detects all genotypes in a panel of 7 to <em>1</em>0 representative isolates of a serotype. In single reactions and in fourplex reactions (containing four primer-probe sets in a single reaction mixture), standard dilutions of virus equivalent to 0.002 PFU of DEN-2, DEN-3, and DEN-4 viruses were detected; the limit of detection of DEN-<em>1</em> virus was 0.5 equivalent PFU. Singleplex and fourplex reactions were evaluated in a panel of 40 viremic serum specimens with <em>1</em>0 specimens per serotype, containing 0.002 to 6,000 equivalent PFU/reaction (0.4 to <em>1</em>.2 x <em>1</em>0(6) PFU/<em>ml</em>). Viral RNA was detected in all viremic serum specimens in singleplex and fourplex reactions. Thus, this serotype-specific, fourplex real-time reverse transcriptase PCR nucleic acid detection assay can be used as a method for differential diagnosis of a specific DEN serotype in viremic dengue patients and as a tool for rapid identification and serotyping of DEN virus isolates.

BACKGROUND

Highly active antiretroviral therapy (HAART) for human immunodeficiency virus (HIV)-<em>1</em> infection allows recovery of CD4 T lymphocytes. Few studies have explored the long-term T-lymphocyte responses to HAART.

METHODS

Plasma HIV-<em>1</em> RNA levels and CD4 and CD8 T-lymphocyte counts were longitudinally analyzed over 4 years in 2235 participants of the Swiss HIV Cohort, commencing HAART between <em>1</em>996 and <em>1</em>997. The CD4 T-lymphocyte count increase, the percentage of individuals with a CD4 T-lymphocyte count of 500/microL or greater and less than 200/microL, and the determinants of CD4 T-lymphocyte recovery were evaluated in individuals treated with continuous (CONT; n = 985) and discontinuous (DISCONT; n = <em>1</em>250) HAART.

RESULTS

At 4 years, 69.5% of subjects (CONT, 84.5%; DISCONT, 53.6%; P<.00<em>1</em>) showed HIV-<em>1</em> RNA levels below 400 copies/mL, while the median CD4 T-lymphocyte count increased from <em>1</em>90/microL to 423/microL (CONT, 486/microL; DISCONT, 343/microL; P<.00<em>1</em>). Of the 2235 participants, 38.8% (CONT, 47.7%; DISCONT, 29.4%; P<.00<em>1</em>) reached a CD4 T-lymphocyte count of 500/microL or greater, but in <em>1</em>5.6%, CD4 T-lymphocyte count remained below 200/microL (CONT, 5.9%; DISCONT, 25.9%; P<.00<em>1</em>). Larger increases in CD4 T-lymphocyte count were associated with higher baseline HIV-<em>1</em> RNA, a larger percentage of undetectable HIV-<em>1</em> RNA levels, lower baseline CD8 T-lymphocyte count, and younger age. Individuals reaching a CD4 T-lymphocyte count of 500/microL or greater at 4 years were characterized by higher nadir and baseline CD4 T-lymphocyte counts and a more sustained reduction of HIV-<em>1</em> RNA levels.

CONCLUSIONS

At 4 years, only 39% of individuals treated with HAART reached a CD4 T-lymphocyte count of 500/microL or greater, and <em>1</em>6% with CD4 T-lymphocyte counts less than 200/microL remained susceptible to opportunistic infections. Treatment interruptions, a poor virologic response, and older age were the major factors negatively affecting the recovery of CD4 T lymphocytes.

OBJECTIVE

The safety, pharmacokinetics, and clinical activity of pazopanib (GW786034), an oral angiogenesis inhibitor targeting vascular endothelial growth factor receptor, platelet-derived growth factor receptor, and c-Kit, were evaluated in patients with advanced-stage refractory solid tumors.

METHODS

Patients were enrolled into sequential dose-escalating cohorts (50 mg three times weekly to 2,000 mg once daily and 300-400 mg twice daily). Escalation or deescalation was based on toxicities observed in the preceding dose cohort. Pharmacokinetic and biomarker samples were obtained. Clinical response was assessed every 9 weeks.

RESULTS

Sixty-three patients were treated (dose escalation, n = 43; dose expansion, n = 20). Hypertension, diarrhea, hair depigmentation, and nausea were the most frequent drug-related adverse events, the majority of which were of grade <em>1</em>/2. Hypertension was the most frequent grade 3 adverse event. Four patients experienced dose-limiting toxicities at 50 mg, 800 mg, and 2,000 mg once daily. A plateau in steady-state exposure was observed at doses of>>or=800 mg once daily. The mean elimination half-life at this dose was 3<em>1</em>.<em>1</em> hours. A mean target trough concentration (C(24))>>or=<em>1</em>5 microg/<em>mL</em> (34 micromol/L) was achieved at 800 mg once daily. Three patients had partial responses (two confirmed, one unconfirmed), and stable disease of>>or=6 months was observed in <em>1</em>4 patients; clinical benefit was generally observed in patients who received doses of>>or=800 mg once daily or 300 mg twice daily.

CONCLUSIONS

Pazopanib was generally well tolerated and showed antitumor activity across various tumor types. A monotherapy dose of 800 mg once daily was selected for phase II studies.

A radioimmunoassay has been developed that permits reliable measurements of plasma arginine vasopressin (AVP) at concentrations as low as 0.5 pg/<em>ml</em> in sample volumes of <em>1</em> <em>ml</em> or less. Nonhormonal immunoreactivity associated with the plasma proteins is eliminated by acetone precipitation before assay, leaving unaltered a component that is immunologically and chromatographically indistinguishable from standard AVP. Storage of plasma results in a decline in AVP concentration and, thus, must be carefully regulated. The plasma AVP values obtained by our method approximate the anticipated levels and vary in accordance with physiologic expections. In recumbent normal subjects, plasma AVP ranged from (mean +/-SD) 5.4+/-3.4 pg/<em>ml</em> after fluid deprivation to <em>1</em>.4+/-0.8 pg/<em>ml</em> after water loading, and correlated significantly with both plasma osmolality (r=0.52; P<0.00<em>1</em>) and urine osmolality (r=0.77; P<0.00<em>1</em>). After fluid restriction, plasma AVP was unifor<em>ml</em>y normal relative to plasma osmolality in patients with nephrogenic diabetes insipidus and primary polydipsia but was distinctly subnormal in all patients with pituitary diabetes insipidus. The infusion of physiologic amounts of posterior pituitary extract caused a dose-related rise in plasma vasopressin that afterwards declined at the expected rate (t(<em>1</em>/2)=22.5+/-4 min). We conclude that, when used appropriately, our radioimmunoassay method provides a useful way of assessing AVP function in man.

A sensitive and specific radioimmunoassay for plasma arginine vasopressin (AVP) has been used to study the effects of blood osmolality and volume in regulating AVP secretion in unanesthetized rats. Under basal conditions, plasma AVP and osmolality were relatively constant, averaging 2.3+/-0.9 (SD) pg/<em>ml</em> and 294+/-<em>1</em>.4 mosmol/kg, respectively. Fluid restriction, which increased osmolality and decreased volume, resulted in a progressive rise in plasma AVP to about <em>1</em>0 times basal levels after 96 h. A 2-3-fold increase in plasma AVP occurred as early as <em>1</em>2 h, when osmolality and volume had each changed by less than 2%. Intraperitoneal injections of hypertonic saline, which had no effect on blood volume, also produced a rise in plasma AVP that was linearly correlated with the rise in osmolality (r>> 0.9) and quantitatively similar to that found during fluid restriction (plasma AVP increased 2-4-fold with each <em>1</em>% increase in osmolality). Intraperitoneal injection of polyethylene glycol, which decreased blood volume without altering osmolality, also increased plasma AVP but this response followed an exponential pattern and did not become significant until volume had decreased by 8% or more. At these levels of hypovolemia, the osmoregulatory system continued to function but showed a lower threshold and increase sensitivity to osmotic stimulation. We conclude that AVP secretion is regulated principally by blood osmolality but that the responsiveness of this mechanism may be significantly altered by modest changes in blood volume.

Early noninvasive detection and characterization of solid tumors and their supporting neovasculature is a fundamental prerequisite for effective therapeutic intervention, particularly antiangiogenic treatment regimens. Emerging molecular imaging techniques now allow recognition of early biochemical, physiological, and anatomical changes before manifestation of gross pathological changes. Although new tumor, vascular, extracellular matrix, and lymphatic biomarkers continue to be discovered, the alpha(nu)beta(3)-integrin remains an attractive biochemical epitope that is highly expressed on activated neovascular endothelial cells and essentially absent on mature quiescent cells. In this study, we report the first in vivo use of a magnetic resonance (MR) molecular imaging nanoparticle to sensitively detect and spatially characterize neovascularity induced by implantation of the rabbit Vx-2 tumor using a common clinical field strength (<em>1</em>.5T). New Zealand White rabbits (2 kg) <em>1</em>2 days after implantation of fresh Vx-2 tumors (2 x 2 x 2 mm(3)) were randomized into one of three treatment groups: (a) alpha(nu)beta(3)-targeted, paramagnetic formulation; (b) nontargeted, paramagnetic formulation; and (c) alpha(nu)beta(3)-targeted nonparamagnetic nanoparticles followed by (2 h) the alpha(nu)beta(3)-targeted, paramagnetic formulation to competitively block magnetic resonance imaging (MRI) signal enhancement. After i.v. systemic injection (0.5 <em>ml</em> of nanoparticles/kg), dynamic T(<em>1</em>)-weighted MRI was used to spatially and temporally determine nanoparticle deposition in the tumor and adjacent tissues, including skeletal muscle. At 2-h postinjection, alpha(nu)beta(3)-targeted paramagnetic nanoparticles increased MRI signal by <em>1</em>26% in asymmetrically distributed regions primarily in the periphery of the tumor. Similar increases in MR contrast were also observed within the walls of some vessels proximate to the tumor. Despite their relatively large size, nanoparticles penetrated into the leaky tumor neovasculature but did not appreciably migrate into the interstitium, leading to a 56% increase in MR signal at 2 h. Pretargeting of the alpha(nu)beta(3)-integrin with nonparamagnetic nanoparticles competitively blocked the specific binding of alpha(nu)beta(3)-targeted paramagnetic nanoparticles, decreasing the MR signal enhancement (50%) to a level attributable to local extravasation. The MR signal of adjacent hindlimb muscle or contralateral control tissues was unchanged by either the alpha(nu)beta(3)-targeted or control paramagnetic agents. Immunohistochemistry of alpha(nu)beta(3)-integrin corroborated the extent and asymmetric distribution of neovascularity observed by MRI. These studies demonstrate the potential of this targeted molecular imaging agent to detect and characterize (both biochemically and morphologically) early angiogenesis induced by minute solid tumors with a clinical <em>1</em>.5 Tesla MRI scanner, facilitating the localization of nascent cancers or metastases, as well as providing tools to phenotypically categorize and segment patient populations for therapy and to longitudinally follow the effectiveness of antitumor treatment regimens.

An eight-electrode conductance catheter previously developed by us and used to determine stroke volume in dogs was applied in human beings and dogs to measure absolute left ventricular volume quantitatively. For calibration we developed the formula V(t) = (<em>1</em>/alpha)(L2/sigma b)G(t) - Vc, where V(t) is time-varying left ventricular volume, alpha is a dimensionless constant, L is the electrode separation, sigma b is the conductivity of blood obtained by a sampling cuvette, and G(t) is the measured conductance within the left ventricular cavity. Vc is a correction term caused by the parallel conductance of structures surrounding the cavity and is measured in two ways. The first method, applicable in the anesthetized animal, consists of temporary reduction of volume to zero by suction. The second method uses a transient change in sigma b by injection of a small bolus of hypertonic saline (dogs) or <em>1</em>0 <em>ml</em> of cold glucose (humans) into the pulmonary artery. The validity of the formula was previously established for the isolated postmortem canine heart. The predicted linearity, slope constant alpha, and accuracy of Vc for the left ventricle in vivo were investigated by comparing the conductance volume data with results from independent methods: electromagnetic blood flow measurement for stroke volume and indicator dilution technique for ejection fraction (dogs), thermal dilution for cardiac output (<em>1</em>2 patients), and single-plane cineventriculography for V(t) (five patients). In all comparisons, linear regression showed high correlation (from r = .82 [n = 46] to r = .988 [n = 20]) while alpha, with one exception, ranged from 0.75 to <em>1</em>.07 and the error in Vc ranged from 0.5% to <em>1</em>6.5% (mean 7%). After positioning of the catheter, no arrhythmias were observed. It is concluded that the conductance catheter provides a reliable and simple method to measure left ventricular volume, giving an on-line, time-varying signal that is easily calibrated. Together with left ventricular pressure obtained through the catheter lumen, the instrument may be used for instantaneous display of pressure-volume loops to facilitate assessment of left ventricular pump performance.

Bloodstream infections due to Candida species cause significant morbidity and mortality. Surveillance for candidemia is necessary to detect trends in species distribution and antifungal resistance. We performed prospective surveillance for candidemia at <em>1</em>6 hospitals in the State of Iowa from <em>1</em> July <em>1</em>998 through 30 June 200<em>1</em>. Using U.S. Census Bureau and Iowa Hospital Association data to estimate a population denominator, we calculated the annual incidence of candidemia in Iowa to be 6.0 per <em>1</em>00,000 of population. Candida albicans was the most common species detected, but 43% of candidemias were due to species other than C. albicans. Overall, only 3% of Candida species were resistant to fluconazole. However, Candida glabrata was the most commonly isolated species other than C. albicans and demonstrated some resistance to azoles (fluconazole MIC at which 90% of the isolates tested are inhibited, 32 microg/<em>ml</em>; <em>1</em>0% resistant, <em>1</em>0% susceptible dose dependent). C. glabrata was more commonly isolated from older patients (P = 0.02) and caused over 25% of candidemias among persons 65 years of age or older. The investigational triazoles posaconazole, ravuconazole, and voriconazole had excellent in vitro activity overall against Candida species. C. albicans is the most important cause of candidemia and remains highly susceptible to available antifungal agents. However, C. glabrata has emerged as an important and potentially antifungal resistant cause of candidemia, particularly among the elderly.

BACKGROUND

Alpha-Klotho (alphaKl) regulates mineral metabolism such as calcium ion (Ca(2+)) and inorganic phosphate (Pi) in circulation. Defects in mice result in clinical features resembling disorders found in human aging. Although the importance of transmembrane-type alphaKl has been demonstrated, less is known regarding the physiological importance of soluble-type alphaKl (salphaKl) in circulation.

OBJECTIVE

The aims of this study were: (<em>1</em>) to establish a sandwich ELISA system enabling detection of circulating serum salphaKl, and (2) to determine reference values for salphaKl serum levels and relationship to indices of renal function, mineral metabolism, age and sex in healthy subjects.

RESULTS

We successively developed an ELISA to measure serum salphaKl in healthy volunteers (n=<em>1</em>42, males 66) of ages (6<em>1</em>.<em>1</em>+/-<em>1</em>8.5year). The levels (mean+/-SD) in these healthy control adults were as follows: total calcium (Ca; 9.46+/-0.4<em>1</em>mg/dL), Pi (3.63+/-0.5<em>1</em>mg/dL), blood urea nitrogen (BUN; <em>1</em>5.7+/-4.3mg/dL), creatinine (Cre; 0.69+/-0.<em>1</em>4mg/dL), <em>1</em>,25 dihydroxyvitamin D (<em>1</em>,25(OH)(2)D; 54.8+/-<em>1</em>7.7pg/mL), intact parathyroid hormone (iPTH; 49.2+/-20.6pg/mL), calcitonin (26.0+/-<em>1</em>2.3pg/mL) and intact fibroblast growth factor (FGF23; 43.8+/-<em>1</em>7.6pg/mL). Serum levels of salphaKl ranged from 239 to <em>1</em>266pg/mL (mean+/-SD; 562+/-<em>1</em>46pg/mL) in normal adults. Although salphaKl levels were not modified by gender or indices of mineral metabolism, salphaKl levels were inversely related to Cre and age. However, salphaKl levels in normal children (n=39, males 23, mean+/-SD; 7.<em>1</em>+/-4.8years) were significantly higher (mean+/-SD; 952+/-282pg/mL) than those in adults (mean+/-SD; 562+/-<em>1</em>46, P<0.00<em>1</em>). A multivariate linear regression analysis including children and adults in this study demonstrated that salphaKl correlated negatively with age and Ca, and positively with Pi. Finally, we measured a serum salphaKl from a patient with severe tumoral calcinosis derived from a homozygous missense mutation of alpha-klotho gene. In this patient, salphaKl level was notably lower than those of age-matched controls.

CONCLUSIONS

We established a detection system to measure human serum salphaKl for the first time. Age, Ca and Pi seem to influence serum salphaKl levels in a normal population. This detection system should be an excellent tool for investigating salphaKl functions in mineral metabolism.

Shear stress regulates endothelial nitric oxide and superoxide (O2-*) production, implicating the role of NADPH oxidase activity. It is unknown whether shear stress regulates the sources of reactive species production, consequent low-density lipoprotein (LDL) modification, and initiation of inflammatory events. Bovine aortic endothelial cells (BAECs) in the presence of 50 microg/<em>mL</em> of native LDL were exposed to (<em>1</em>) pulsatile flow with a mean shear stress (tau(ave)) of 25 dyne/cm2 and (2) oscillating flow at tau(ave) of 0. After 4 hours, aliquots of culture medium were collected for high-performance liquid chromatography analyses of electronegative LDL species, described as LDL- and LDL2-. In response to oscillatory shear stress, gp9<em>1</em>phox mRNA expression was upregulated by 2.9+/-0.3-fold, and its homologue, Nox4, by 3.9+/-0.9-fold (P<0.05, n=4), with a corresponding increase in O2-* production rate. The proportion of LDL- and LDL2- relative to static conditions increased by 67+/-<em>1</em>7% and 30+/-7%, respectively, with the concomitant upregulation of monocyte chemoattractant protein-<em>1</em> expression and increase in monocyte/BAEC binding (P<0.05, n=5). In contrast, pulsatile flow downregulated both gp9<em>1</em>phox and Nox4 mRNA expression (by <em>1</em>.8+/-0.2-fold and 3.0+/-0.<em>1</em>2-fold, respectively), with an accompanying reduction in O2-* production, reduction in the extent of LDL modification (5<em>1</em>+/-<em>1</em>2% for LDL- and 30+/-7% for LDL2-), and monocyte/BAEC binding. The flow-dependent LDL oxidation is determined in part by the NADPH oxidase activity. The formation of modified LDL via O2-* production may also affect the regulation of monocyte chemoattractant protein-<em>1</em> expression and monocyte/BAEC binding.

BACKGROUND

Essential hypertension has been recognized as a disease resulting from a combination of environmental and genetic factors. Recent studies demonstrated that microRNAs (miRNAs) are involved in cardiac hypertrophy and heart failure. However, little is known about the roles of miRNAs in essential hypertension.

RESULTS

Using microarray-based miRNA expression profiling, we compared the miRNA expressions in plasma samples from <em>1</em>3 hypertensive patients and 5 healthy control subjects. Twenty-seven miRNAs were found to be differentially expressed. The expressions of selected miRNAs (miR-296-5p, let-7e, and a human cytomegalovirus [HCMV]-encoded miRNA, hcmv-miR-UL<em>1</em><em>1</em>2) were validated independently in plasma samples from 24 hypertensive patients and 22 control subjects. The absolute expression levels of hcmv-miR-UL<em>1</em><em>1</em>2, miR-296-5p, and let-7e were further determined in <em>1</em>27 patients and 67 control subjects (fold changes are 2.5, 0.5, and <em>1</em>.7 respectively; all P<0.000<em>1</em>). Additionally, we demonstrated that interferon regulatory factor <em>1</em> is a direct target of hcmv-miR-UL<em>1</em><em>1</em>2. Increased HCMV seropositivity and quantitative titers were found in the hypertension group compared with the control group (52.7% versus 30.9%, P=0.0005; <em>1</em>870 versus 54 copies per <em>1</em> <em>mL</em> plasma, P<0.000<em>1</em>). Seropositivity, log-transformed copies of HCMV, and hcmv-miR-UL<em>1</em><em>1</em>2 were independently associated with an increased risk of hypertension (odds ratio, 2.48; 95% confidence interval, <em>1</em>.48 to 4.<em>1</em>5; P=0.0005; odds ratio, <em>1</em>.97; 95% confidence interval, <em>1</em>.58 to 2.46; P<0.000<em>1</em>; and odds ratio, 2.55; 95% confidence interval, <em>1</em>.98 to 3.27; P<0.000<em>1</em>, respectively).

CONCLUSIONS

We report for the first time a circulating miRNA profile for hypertensive patients and demonstrate a novel link between HCMV infection and essential hypertension. These findings may reveal important insights into the pathogenesis of essential hypertension.

BACKGROUND

URL: http://www.clinicaltrials.gov. UNIQUE IDENTIFIER: NCT00420784.

OBJECTIVE

Tumor necrosis factor and high mobility group box <em>1</em> are critical cytokine mediators of inflammation. The efferent vagus nerve inhibits cytokine release through alpha7-nicotinic acetylcholine receptor-mediated cholinergic signaling. Here we studied whether GTS-2<em>1</em>, a selective alpha7-nicotinic acetylcholine receptor agonist, inhibits proinflammatory cytokines in vitro and in vivo and improves survival in murine endotoxemia and severe sepsis.

METHODS

Randomized and controlled in vitro and in vivo study.

METHODS

Research laboratory and animal facility rooms.

METHODS

RAW 264.7 cells and BALB/c mice treated with endotoxin or subjected to cecal ligation and puncture (CLP).

METHODS

RAW 264.7 cells were exposed to endotoxin (4 ng/mL or <em>1</em>0 ng/mL) in the presence or absence of GTS-2<em>1</em> (<em>1</em>-<em>1</em>00 muM), and tumor necrosis factor and high mobility group box <em>1</em> release and nuclear factor-kappaB activation were analyzed. Mice were treated with GTS-2<em>1</em> (0.4 mg/kg or 4 mg/kg, intraperitoneally) or saline 30 mins before endotoxin (6 mg/kg, intraperitoneally), and serum tumor necrosis factor was analyzed <em>1</em>.5 hrs after the onset of endotoxemia. In survival experiments, mice were treated with GTS-2<em>1</em> (0.4 or 4.0 mg/kg, intraperitoneally) or saline 30 mins before and 6 hrs after endotoxin and then twice daily for 3 days. Severe sepsis was induced by CLP. Mice were treated with GTS-2<em>1</em> (4 mg/kg) or saline immediately and 6 hrs and 24 hrs after CLP, and serum high mobility group box <em>1</em> was analyzed 30 hrs after CLP. In survival experiments, GTS-2<em>1</em> (0.4 or 4 mg/kg) treatment was initiated 24 hrs after CLP and continued twice daily for 3 days.

RESULTS

GTS-2<em>1</em> dose-dependently inhibited tumor necrosis factor and high mobility group box <em>1</em> release and nuclear factor-kappaB activation in vitro. GTS-2<em>1</em> (4 mg/kg) significantly inhibited serum tumor necrosis factor during endotoxemia and improved survival (p < .000<em>1</em>). GTS-2<em>1</em> (4 mg/kg) significantly inhibited serum high mobility group box <em>1</em> levels in CLP mice and improved survival (p < .0006).

CONCLUSIONS

These findings are of interest for the development of alpha7-nicotinic acetylcholine receptor agonists as a new class of anti-inflammatory therapeutics.

After administration of enriched [<em>1</em>-<em>1</em>3C]glucose, the rate of <em>1</em>3C label incorporation into glutamate C4, C3, and C2, glutamine C4, C3, and C2, and aspartate C2 and C3 was simultaneously measured in six normal subjects by <em>1</em>3C NMR at 4 Tesla in 45-<em>ml</em> volumes encompassing the visual cortex. The resulting eight time courses were simultaneously fitted to a mathematical model. The rate of (neuronal) tricarboxylic acid cycle flux (V(PDH)), 0.57 +/- 0.06 micromol. g(-<em>1</em>). min(-<em>1</em>), was comparable to the exchange rate between (mitochondrial) 2-oxoglutarate and (cytosolic) glutamate (Vx), 0.57 +/- 0.<em>1</em>9 micromol. g(-<em>1</em>). min(-<em>1</em>)), which may reflect to a large extent malate-aspartate shuttle activity. At rest, oxidative glucose consumption [CMR(Glc(ox))] was 0.4<em>1</em> +/- 0.03 miccromol. g(-<em>1</em>). min(-<em>1</em>), and (glial) pyruvate carboxylation (VPC) was 0.09 +/- 0.02 micromol. g(-<em>1</em>). min(-<em>1</em>). The flux through glutamine synthetase (Vsyn) was 0.26 +/- 0.06 micromol. g(-<em>1</em>). min(-<em>1</em>). A fraction of Vsyn was attributed to be from (neuronal) glutamate, and the corresponding rate of apparent glutamatergic neurotransmission (VNT) was 0.<em>1</em>7 +/- 0.05 micromol. g(-<em>1</em>). min(-<em>1</em>). The ratio [VNT/CMR(Glcox)] was 0.4<em>1</em> +/- 0.<em>1</em>4 and thus clearly different from a <em>1</em>:<em>1</em> stoichiometry, consistent with a significant fraction (approximately 90%) of ATP generated in astrocytes being oxidative. The study underlines the importance of assumptions made in modeling <em>1</em>3C labeling data in brain.

BACKGROUND

The long-term renal prognosis of patients with diarrhea-associated hemolytic uremic syndrome (HUS) remains controversial.

OBJECTIVE

To quantify the long-term renal prognosis of patients with diarrhea-associated HUS and to identify reasons for different estimates provided in the literature.

METHODS

We searched MEDLINE and Experta Medica (EMBASE) bibliographic databases and conference proceedings, and we contacted experts until February 2003. We also searched the Institute for Scientific Information index and reference lists of all studies that fulfilled our eligibility criteria. The search strategy included the terms hemolytic-uremic syndrome, purpura, thrombotic thrombocytopenic, Escherichia coli O<em>1</em>57, longitudinal studies, kidney diseases, hypertension, and proteinuria

METHODS

Any study that followed up <em>1</em>0 or more patients with primary diarrhea-associated HUS for at least <em>1</em> year for renal sequelae.

METHODS

Two authors independently abstracted data on study and patient characteristics, renal measures, outcomes, and prognostic features. Disagreements were resolved by a third author or by consensus.

RESULTS

Forty-nine studies of 3476 patients with a mean follow-up of 4.4 years (range, <em>1</em>-22 years at last follow-up) from <em>1</em>8 countries, <em>1</em>950 to 200<em>1</em>, were summarized. At the time of recruitment, patients were aged <em>1</em> month to <em>1</em>8 years. In the different studies, death or permanent end-stage renal disease (ESRD) ranged from 0% to 30%, with a pooled incidence of <em>1</em>2% (95% confidence interval [CI], <em>1</em>0%-<em>1</em>5%). A glomerular filtration rate lower than 80 mL/min per <em>1</em>.73 m2, hypertension, or proteinuria was extremely variable and ranged from 0% to 64%, with a pooled incidence of 25% (95% CI, 20%-30%). A higher severity of acute illness was strongly associated with worse long-term prognosis. Studies with a higher proportion of patients with central nervous system symptoms (coma, seizures, or stroke) had a higher proportion of patients who died or developed permanent ESRD at follow-up (explaining 44% of the between-study variability, P =.0<em>1</em>). Studies with a greater proportion of patients lost to follow-up also described a worse prognosis (P =.00<em>1</em>) because these patients were typically healthier than those followed up. One or more years after diarrhea-associated HUS, patients with a predicted creatinine clearance higher than 80 mL/min per <em>1</em>.73 m2, no overt proteinuria, and no hypertension appeared to have an excellent prognosis.

CONCLUSIONS

Death or ESRD occurs in about <em>1</em>2% of patients with diarrhea-associated HUS, and 25% of survivors demonstrate long-term renal sequelae. Patients lost to follow-up contribute to worse estimates in some studies. The severity of acute illness, particularly central nervous system symptoms and the need for initial dialysis, is strongly associated with a worse long-term prognosis.

BACKGROUND

The integrase inhibitor elvitegravir (EVG) has been co-formulated with the CYP3A4 inhibitor cobicistat (COBI), emtricitabine (FTC), and tenofovir disoproxil fumarate (TDF) in a single tablet given once daily. We compared the efficacy and safety of EVG/COBI/FTC/TDF with standard of care-co-formulated efavirenz (EFV)/FTC/TDF-as initial treatment for HIV infection.

METHODS

In this phase 3 trial, treatment-naive patients from outpatient clinics in North America were randomly assigned by computer-generated allocation sequence with a block size of four in a <em>1</em>:<em>1</em> ratio to receive EVG/COBI/FTC/TDF or EFV/FTC/TDF, once daily, plus matching placebo. Patients and study staff involved in giving study treatment, assessing outcomes, and collecting and analysing data were masked to treatment allocation. Eligibility criteria included screening HIV RNA concentration of 5000 copies per <em>mL</em> or more, and susceptibility to efavirenz, emtricitabine, and tenofovir. The primary endpoint was HIV RNA concentration of fewer than 50 copies per <em>mL</em> at week 48. The study is registered with ClinicalTrials.gov, number NCT0<em>1</em>095796.

RESULTS

700 patients were randomly assigned and treated (348 with EVG/COBI/FTC/TDF, 352 with EFV/FTC/TDF). EVG/COBI/FTC/TDF was non-inferior to EFV/FTC/TDF; 305/348 (87·6%) versus 296/352 (84·<em>1</em>%) of patients had HIV RNA concentrations of fewer than 50 copies per <em>mL</em> at week 48 (difference 3·6%, 95% CI -<em>1</em>·6% to 8·8%). Proportions of patients discontinuing drugs for adverse events did not differ substantially (<em>1</em>3/348 in the EVG/COBI/FTC/TDF group vs <em>1</em>8/352 in the EFV/FTC/TDF group). Nausea was more common with EVG/COBI/FTC/TDF than with EFV/FTC/TDF (72/348 vs 48/352) and dizziness (23/348 vs 86/352), abnormal dreams (53/348 vs 95/352), insomnia (30/348 vs 49/352), and rash (22/348 vs 43/352) were less common. Serum creatinine concentration increased more by week 48 in the EVG/COBI/FTC/TDF group than in the EFV/FTC/TDF group (median <em>1</em>3 μmol/L, IQR 5 to 20 vs <em>1</em> μmol/L, -6 to 8; p<0·00<em>1</em>).

CONCLUSIONS

If regulatory approval is given, EVG/COBI/FTC/TDF would be the only single-tablet, once-daily, integrase-inhibitor-based regimen for initial treatment of HIV infection.

BACKGROUND

Gilead Sciences.