Quantitative trait loci (QTL) for low temperature tolerance at the young microspore stage in rice (Oryza sativa L.) in Australian breeding material.

Low temperatures at the young microspore stage (YMS) decreases spikelet fertility and is a major limiting factor to rice production in temperate Australia. Low temperature tolerance is a difficult trait to phenotype, hence there is a strong desire for the identification of quantitative trait loci (QTL) for their use in marker-assisted selection (MAS). Association mapping was used in several breeding populations with a known source of low temperature tolerance, Norin PL8, to identify QTL for low temperature tolerance. A novel QTL for spikelet fertility was identified on chromosome 6, qYMCT6.1, in which the Australian variety, Kyeema, was the donor for increased fertility. Additional five genomics regions were identified that co-located with previously reported QTL, two of which have been previously cloned. Additionally, for the first time a QTL for spikelet fertility qYMCT10.1, has been shown to co-locate with the number of dehisced anthers qYMCTF10.1 which increases the shedding of pollen from the anthers. This study revealed one new QTL for low temperature tolerance at YMS in temperate japonica germplasm and identified an additional five previously reported. These QTL will be utilised for MAS in the Australian rice breeding program and may have merit for temperate breeding programs globally.

Acute esophageal necrosis (black esophagus) complicating calcific uremic arteriolopathy
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The current case report describes a chronic hemodialysis patient presenting with painful penile ulceration that was clinically and histologically proven to be related to calcific uremic arteriolopathy. The patient subsequently developed severe upper gastrointestinal bleeding that was both endoscopically and histologically shown to be due to acute esophageal necrosis (AEN), also known as necrotizing esophagitis and "black esophagus". AEN is a rare condition characterized by diffuse necrosis of the esophageal mucosa. The condition is diagnosed endoscopically with demonstration of circumferential mucosal necrosis involving the distal esophagus that can extend proximally. Mortality rates for both calcific uremic ateriolopathy and acute esophageal necrosis are high. Management of both conditions is reviewed. The patient recovered from the acute illness, but expired 6 months later due to progressive failure to thrive. To our knowledge, AEN has not previously been described secondary to calcific uremic arteriolopathy.
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Design and fabrication of constant-pitch circular surface-relief diffraction gratings on disperse red 1 glass.

Circular surface-relief diffraction gratings with a constant pitch were photo-inscribed on thin films of a disperse red 1 functionalized glass-forming compound using a novel holographic technique. Various light-interfering metallic fixtures, which consisted of annular rings with a sloped and polished inner surface, were designed and fabricated. Each of them allowed the inscription of stable and high-quality circular diffraction gratings with pitches ranging from approximately 600-1400 nm and depths up to 250 nm. This was accomplished by exposure to a collimated laser beam with an irradiance of 604 mW/cm2 for 350 s. The resulting gratings had a diameter of 11.4 mm and had the advantage of being produced in a simple single-step procedure with no postprocessing or specialized equipment. The pitch and diameter of these circular gratings were dependent on the fixture geometry, while the depth was related to the exposure time.

Reduced cardiorespiratory fitness in adult survivors of childhood acute lymphoblastic leukemia.

BACKGROUND: Adult survivors of childhood acute lymphoblastic leukemia (ALL) are at increased cardiovascular risk. Studies of factors including treatment exposures that may modify risk of low cardiorespiratory fitness in this population have been limited. PROCEDURE: To assess cardiorespiratory fitness, maximal oxygen uptake (VO2 max) was measured in 115 ALL survivors (median age, 23.5 years; range 18-37). We compared VO2 max measurements for ALL survivors to those estimated from submaximal testing in a frequency-matched (age, gender, race/ethnicity) 2003-2004 National Health and Nutritional Examination Survey (NHANES) cohort. Multivariable linear regression models were constructed to evaluate the association between therapeutic exposures and outcomes of interest. RESULTS: Compared to NHANES participants, ALL survivors had a substantially lower VO2 max (mean 30.7 vs. 39.9 ml/kg/min; adjusted P < 0.0001). For any given percent total body fat, ALL survivors had an 8.9 ml/kg/min lower VO2 max than NHANES participants. For key treatment exposure groups (cranial radiotherapy [CRT], anthracycline chemotherapy, or neither), ALL survivors had substantially lower VO2 max compared with NHANES participants (all comparisons, P < 0.001). Almost two-thirds (66.7%) of ALL survivors were classified as low cardiorespiratory fitness compared with 26.3% of NHANES participants (adjusted P < 0.0001). In multivariable models including only ALL survivors, treatment exposures were modestly associated with VO2 max. Among females, CRT was associated with low VO2 max (P = 0.02), but anthracycline exposure was not (P = 0.58). In contrast, among males, anthracycline exposure ≥ 100 mg/m(2) was associated with low VO2 max (P = 0.03), but CRT was not (P = 0.54). CONCLUSION: Adult survivors of childhood ALL have substantially lower levels of cardiorespiratory fitness compared with a similarly aged non-cancer population.

Genomic Regions and Floral Traits Contributing to Low Temperature Tolerance at Young Microspore Stage in a Rice (Oryza sativa L.) Recombinant Inbred Line Population of Sherpa/IRAT109.

Aerobic rice production (AP) consumes less water compared to flooded systems. Developing genotypes and identifying genomic regions associated with low temperature (LT) tolerance at the young microspore stage (YMS) is imperative for AP, particularly for temperate regions. Using a recombinant inbred line population derived from the Australian LT tolerant variety Sherpa, experiments were conducted to map and dissect quantitative trait loci (QTL) associated with spikelet sterility (SS) after exposure to LT and to investigate floral traits contributing to the development of lower SS. Significant genotypic variation for SS was observed in the population after exposure to LT at YMS. Three genomic regions associated with SS, qYMCT3, qYMCT4, and qYMCT8.1 were identified in chromosomes 3, 4, and 8 respectively, using multiple QTL models explaining 22.4% of the genotypic variation. Introgression of the favorable allele from qYMCT3 was estimated to reduce SS by up to 15.4%. A co-locating genomic region with qYMCT3, qDTHW3.1 was identified as the major QTL affecting days to heading and explained as much as 44.7% of the genotypic variation. Whole-genome sequence and bioinformatic analyses demonstrated OsMADS50 as the candidate gene for qYMCT3/qDTHW3.1 and to our knowledge, this was the first attempt in connecting the role of OsMADS50 in both LT and flowering in rice. Differential sets selected for extreme SS showed LT tolerant genotype group produced higher total pollen per spikelet resulting in a higher number of dehisced anthers and pollen on stigma and eventually, lower SS than THE sensitive group. The relationship between these key floral traits with SS was induced only after exposure to LT and was not observed in warm ideal temperature conditions. Identification of elite germplasm with favorable QTL allele and combinations, gene cloning, and pyramiding with additional high-value QTL for key traits should empower breeders to develop AP adapted genotypes for temperate growing regions, and ultimately produce climate-resilient rice.

Adult Intussusception in Chronic Marijuana Users.

Intussusception is common in children, but it is rare in adults. The most common causes of adult intussusception (AI) are due to a pathological lead point with a common etiology being malignancy. Intra-luminal irritants should be considered the possible etiology of intussusception in patients without a pathological lead point. Marijuana use has increased dramatically in the United States over the last decade. With increasing public acceptance and legalization of marijuana, various adverse side effects have become more prominent. Marijuana has been shown to disrupt gastrointestinal tract motility by inhibiting cholinergic mechanisms. Here we describe four cases of AI who are chronic marijuana users. This well-referenced review gives attention to the harmful effects of marijuana, given the increasing use of marijuana and its derivatives in the United States.

Antenatal depression: a rationale for studying exercise.

BACKGROUND: Major depressive disorder (MDD) in pregnancy or antenatal depression poses unique treatment challenges and has serious consequences for mothers, unborn babies, and families when untreated. This review presents current knowledge on exercise during pregnancy, antidepressant effects of exercise, and the rationale for the specific study of exercise for antenatal depression. METHOD: A systematic literature review was performed using English language articles published in Medline, PsycINFO, CINAHL, and the Cochrane Library from 1985 to January 2010. RESULTS: There is a broad literature supporting the antidepressant effects of exercise, but a paucity of studies specifically for antenatal depression. A small number of observational studies have reported that regular physical activities improve self-esteem and reduce symptoms of anxiety and depression during pregnancy. To date, there have not been randomized controlled studies of exercise for the treatment of MDD in pregnant women. CONCLUSIONS: Systematic studies are needed to assess exercise as a treatment alternative for MDD during pregnancy. In consideration of the benefits of exercise for the mother and baby, and the burden of depression, studies are needed to determine the role of exercise for pregnant women with depression.

Randomized comparison of the effects of rosiglitazone vs. placebo on peak integrated cardiovascular performance, cardiac structure, and function.

AIMS: To assess the effect of rosiglitazone on cardiovascular performance and cardiac function. METHODS AND RESULTS: One hundred and fifty type 2 diabetes patients with cardiovascular disease (CVD) or ≥ 1 other CVD risk factor were randomized to receive rosiglitazone vs. placebo for 6 months. The primary outcome was peak oxygen uptake indexed to fat-free mass (VO(2peak)-FFM) during maximum exercise. A subset of 102 subjects underwent cardiac magnetic resonance imaging (cMRI). On hundred and eight subjects completed the study, including 75 completing the cMRI substudy. No significant differences were observed in mean VO(2peak)-FFM between rosiglitazone and placebo (26.1 ± 7.0 vs. 27.6 ± 6.6 mL/kg-FFM/min; P = 0.26). Compared with placebo, the rosiglitazone group had lower hematocrit (38 vs. 41%; P < 0.001) and more peripheral oedema (53.7 vs. 33.3%; P = 0.03). In the cMRI substudy, compared with placebo, the rosiglitazone group had larger end-diastolic volume (128.1 vs. 112.0 mL; P = 0.01) and stroke volume (83.7 vs. 72.9 mL; P = 0.01), and a trend toward increased peak ventricular filling rate (79.4 vs. 60.5; P = 0.07). CONCLUSION: Rosiglitazone increased peripheral oedema but had no pernicious effects on cardiovascular performance or cardiac function, with modest improvement in selected cMRI measures. Changes in indirect markers of plasma volume suggest expansion with rosiglitazone. TRIAL REGISTRATION: clinicaltrials.gov identifier: NCT00424762.

QTL Validation and Development of SNP-Based High Throughput Molecular Markers Targeting a Genomic Region Conferring Narrow Root Cone Angle in Aerobic Rice Production Systems.

Aerobic rice production (AP) provides potential solutions to the global water crisis by consuming less water than traditional permanent water culture. Narrow root cone angle (RCA), development of deeper rooting and associated genomic regions are key for AP adaptation. However, their usefulness depends on validation across genetic backgrounds and development of linked markers. Using three F2 populations derived from IRAT109, qRCA4 was shown to be effective in multiple backgrounds, explaining 9.3-17.3% of the genotypic variation and introgression of the favourable allele resulted in 11.7-15.1° narrower RCA. Novel kompetitive allele specific PCR (KASP) markers were developed targeting narrow RCA and revealed robust quality metrics. Candidate genes related with plant response to abiotic stress and root development were identified along with 178 potential donors across rice subpopulations. This study validated qRCA4's effect in multiple genetic backgrounds further strengthening its value in rice improvement for AP adaptation. Furthermore, the development of novel KASP markers ensured the opportunity for its seamless introgression across pertinent breeding programs. This work provides the tools and opportunity to accelerate development of genotypes with narrow RCA through marker assisted selection in breeding programs targeting AP, which may ultimately contribute to more sustainable rice production where water availability is limited.

Stable and Novel Quantitative Trait Loci (QTL) Confer Narrow Root Cone Angle in an Aerobic Rice (Oryza sativa L.) Production System.

BACKGROUND: Aerobic rice production (AP) may be a solution to the looming water crisis by utilising less water compared to traditional flooded culture. As such, development of genotypes with narrow root cone angle (RCA) is considered a key AP adaptation trait as it could lead to deeper rooting and ensure water uptake at depth. Quantitative trait loci (QTL) and genes associated with rooting angle have been identified in rice, but usually in conventional transplanted systems or in upland and drought conditions. This study aimed to identify QTL associated with RCA in AP systems using a recombinant inbred line population derived from IRAT109. RESULTS: Four experiments conducted in glasshouse and aerobic field conditions revealed significant genotypic variation existed for RCA in the population. Single and multiple QTL models identified the presence of eight QTL distributed in chromosomes 1, 2, 3, 4, and 11. Combined, these QTL explained 36.7-51.2% of the genotypic variance in RCA present in the population. Two QTL, qRCA1.1 and qRCA1.3, were novel and may be new targets for improvement of RCA. Genotypes with higher number of favourable QTL alleles tended to have narrower RCA. qRCA4 was shown to be a major and stable QTL explaining up to 24.3% of the genotypic variation, and the presence of the target allele resulted in as much as 8.6° narrower RCA. Several genes related to abiotic stress stimulus response were found in the qRCA4 region. CONCLUSION: Stable and novel genomic regions associated with RCA have been identified. Genotypes which had combinations of these QTL, resulted in a narrower RCA phenotype. Allele mining, gene cloning, and physiological dissection should aid in understanding the molecular function and mechanisms underlying RCA and these QTL. Ultimately, our work provides an opportunity for breeding programs to develop genotypes with narrow RCA and deep roots for improved adaptation in an AP system for sustainable rice production.

Natural History of Non-Alcoholic Fatty Liver Disease: A Study With Paired Liver Biopsies.

BACKGROUND: Although there is unequivocal evidence for progression of nonalcoholic steatohepatitis (NASH) to cirrhosis, there is uncertainty with regard to the progression to nonalcoholic fatty liver (NAFL) and NASH. AIMS: We investigated the rate of progression to NASH and advanced fibrosis in patients with nonalcoholic fatty liver disease (NAFLD) and assessed the factors associated with such progression. METHODS: Histological assessment was performed in 36 patients with NAFLD with paired liver biopsies (≥1 year apart; median, 3.8 years; range, 1-10.33 years). NASH Clinical Research Network (NASH CRN) criteria were used to assess NAFLD Activity Score (NAS). RESULTS: At baseline, 26 (72%) patients had NAFL and 10 (28%) patients had NASH. At follow-up, 27% NAFL progressed to NASH (NAS score ≥5), and 50% of patients with NASH no longer met the criteria of NASH. Fibrosis progressed in 15 (42%), regressed in 9 (25%), and remained stable in 12 (33%) patients overall. Thirty-five percent of patients with NAFL had fibrosis progression. The incidence of type 2 diabetes mellitus (T2DM) was higher in patients with NASH versus NAFL (40% vs. 27%). Both at the time of baseline and follow-up, liver biopsies, composite models of noninvasive scores such as Fibrosis-4 (FIB-4) score and NAFLD fibrosis score, and ratio of aspartate aminotransferase (AST) to alanine aminotransferase (ALT) were all significantly higher in progressors than in nonprogressors. CONCLUSIONS: NAFLD is a dynamic liver disease with varying degrees of progression and regression. T2DM was strongly associated with fibrosis progression. Noninvasive fibrosis scores such as AST/ALT ratio, FIB-4 score, and NAFLD fibrosis score can identify those at risk of fibrosis progression.

Accuracy of Noninvasive Fibrosis Scoring Systems in African American and White Patients With Nonalcoholic Fatty Liver Disease.

OBJECTIVES: Nonalcoholic fatty liver disease fibrosis score (NFS), fibrosis-4 (FIB-4) score, aspartate aminotransferase (AST)-to-platelet ratio index (APRI) score, and AST-alanine aminotransferase (ALT) ratio are noninvasive fibrosis scoring systems for the staging of liver fibrosis in patients with chronic liver disease. METHODS: In a large cohort of patients with nonalcoholic fatty liver disease, we compared AST-ALT ratio, NFS, FIB-4 score, and APRI score in predicting advanced fibrosis (defined as fibrosis stage ≥ 3) in histologically confirmed African American (AA) and white patients. We identified 907 patients: 677 (74.6%) white and 230 (25.3%) AA patients with nonalcoholic fatty liver disease. RESULTS: Of the 907 patients, 115 (12.8%) patients had advanced fibrosis (stages 3 and 4) in the total cohort: 6 (2.6%) AAs, and 109 (16.2%) whites. In AAs, the area under the receiver operating characteristic (area under the curve) for predicting advanced fibrosis was 0.58 by NFS, 0.86 by APRI score, 0.77 by FIB-4 score, and 0.65 by AST-ALT ratio. In whites, the area under the receiver operating characteristic for predicting advanced fibrosis was 0.82 by NFS, 0.82 by APRI score, 0.88 by FIB-4 score, and 0.76 by AST-ALT ratio. In the AA population, NFS > 0.675, FIB-4 score > 2.67, and APRI score > 1.5 each has a negative predictive value of 98%, whereas the negative predictive values in whites are 91%, 88%, and 85%, respectively. DISCUSSION: Noninvasive fibrosis scoring systems can reliably exclude advanced fibrosis in both AAs and whites and have acceptable discriminatory ability to predict advanced fibrosis in whites. The utility of noninvasive fibrosis scoring systems in predicting advanced fibrosis in AAs needs further validation in a larger multicenter cohort.

The anti-inflammatory and antioxidant effects of pigmented rice consumption in an obese cohort.

The development of lifestyle diseases in the obese has been attributed to higher levels of inflammation and free radical mediated oxidative stress. The antioxidant and anti-inflammatory properties of polyphenols in pigmented rice varieties could have potential to neutralize oxidative stress and modulate inflammatory responses in the obese. A cross-over dietary intervention human clinical trial was conducted with three pigmented rice varieties chosen from previous chemical and in vitro antioxidant and anti-inflammatory screening. Obese (n = 22, BMI > 30) sedentary participants consumed one cup of pigmented rice (Reiziq (brown), Purple (purple) and Yunlu29 (red)). Blood samples were collected prior consumption (baseline) and at set time points of 30 minutes, 1 hour, 2 hours and 4 hours post rice consumption. The collected blood samples were analysed for antioxidant and inflammatory biomarkers. Total antioxidant activity increased (p < 0.001) at the 1 hour time point by 40.3% post purple rice consumption. The red rice variety, Yunlu29 increased antioxidant activity at the 30 minute (p < 0.001) and 1 hour (p < 0.01) time point by 29.5% and 21.2% respectively. Lipid peroxidation biomarker, malondialdehyde (MDA), decreased (p < 0.05) at the 30 minute time point by 6.8% post purple rice consumption. At the 4 hour time point MDA levels was significantly reduced (p < 0.001) by the red rice variety Yunlu29, by 9.6%. Pro-inflammatory cytokine, interleukin-10 (IL-10), was significantly (p < 0.0001) reduced by 3.1% 30 minutes post purple rice consumption. In contrast, Yunlu29 (red) reduced interleukin-6 levels by 13.6% and 11.0% at the 30 minute and 1 hour time points respectively. Both the purple (p < 0.01) and red (p < 0.001) varieties significantly reduced interleukin-12p70 concentrations at 30 minutes by 8.7% and 10.3% respectively. Reiziq (brown) did not affect any of the biomarkers analysed in this study. The outcomes of this study highlight that polyphenols found in pigmented rice may play a key role in targeting specific therapeutic pathways in obesity-related oxidative stress and inflammation.

The anti-inflammatory and antioxidant effects of acute consumption of pigmented rice in humans.

The pathogenesis of lifestyle diseases has been significantly correlated to high levels of oxidative stress and pro-inflammation. The antioxidant and anti-inflammatory properties of polyphenols in coloured rice varieties could have potential to neutralize oxidative stress and modulate inflammatory responses. A cross-over design, randomised, dietary intervention human clinical trial was conducted on a pre-screened healthy population (n = 24) investigating the antioxidant and anti-inflammatory potential of pigmented rice (purple, red and brown) varieties. Post baseline blood samples collection volunteers consumed a serve of cooked pigmented rice. Blood samples were collected at 30-minutes, 1, 2 and 4-hours post rice consumption. A one-week wash-out period between each supplementation bout (rice variety) was conducted. Blood and biochemical parameters were analysed on baseline blood samples. Antioxidant activity, malondialdehyde (MDA) and a pro-inflammatory cytokine panel were analysed on the blood samples collected. Post purple rice consumption, antioxidant activity increased (p < 0.0001) by 70.5% and maintained elevated for all time points. The red rice variety Yunlu29, significantly (p < 0.005) reduced MDA levels by 9.2% at the 30-minute time point. Purple rice demonstrated a significant (p < 0.05) decrease by 4.0% at the 30-minute time point only. Purple rice significantly decreased TNF-α levels at the 1-hour (p < 0.05) and 4-hour (p < 0.005) time points by 21.9% and 25.4% respectively. IL-6 concentrations were significantly reduced at 1 and 2-hour post Purple (p < 0.05; 11.7%) and Yunlu29 (red) (p < 0.01; 14.1%) consumption respectively. The brown rice variety did not affect any parameters tested. The outcomes of this study, highlight that polyphenols found in pigmented rice may play a key role in targeting specific oxidative stress and inflammatory therapeutic pathways. Pigmented rice varieties may serve as a potential functional food in reducing risk factors associated with lifestyle diseases.

Leptin-replacement therapy for lipodystrophy.

BACKGROUND: The adipocyte hormone leptin is important in regulating energy homeostasis. Since severe lipodystrophy is associated with leptin deficiency, insulin resistance, hypertriglyceridemia, and hepatic steatosis, we assessed whether leptin replacement would ameliorate this condition. METHODS: Nine female patients (age range, 15 to 42 years; eight with diabetes mellitus) who had lipodystrophy and serum leptin levels of less than 4 ng per milliliter (0.32 nmol per milliliter) received recombinant methionyl human leptin (recombinant leptin). Recombinant leptin was administered subcutaneously twice a day for four months at escalating doses to achieve low, intermediate, and high physiologic replacement levels of leptin. RESULTS: During treatment with recombinant leptin, the serum leptin level increased from a mean (+/- SE) of 1.3 +/- 0.3 ng per milliliter to 11.1 +/- 2.5 ng per milliliter (0.1 +/- 0.02 to 0.9 +/- 0.2 nmol per milliliter). The absolute decrease in the glycosylated hemoglobin value was 1.9 percent (95 percent confidence interval, 1.1 to 2.7 percent; P=0.001) in the eight patients with diabetes. Four months of therapy decreased average triglyceride levels by 60 percent (95 percent confidence interval, 43 to 77 percent; P<0.001) and liver volume by an average of 28 percent (95 percent confidence interval, 20 to 36 percent; P=0.002) in all nine patients and led to the discontinuation of or a large reduction in antidiabetes therapy. Self-reported daily caloric intake and the measured resting metabolic rate also decreased significantly with therapy. Overall, recombinant leptin therapy was well tolerated. CONCLUSIONS: Leptin-replacement therapy improved glycemic control and decreased triglyceride levels in patients with lipodystrophy and leptin deficiency. Leptin deficiency contributes to the insulin resistance and other metabolic abnormalities associated with severe lipodystrophy.

Maximal oxygen uptake as a parametric measure of cardiorespiratory capacity.

INTRODUCTION: Maximal oxygen uptake (.VO2max) was defined by Hill and Lupton in 1923 as the oxygen uptake attained during maximal exercise intensity that could not be increased despite further increases in exercise workload, thereby defining the limits of the cardiorespiratory system. This concept has recently been disputed because of the lack of published data reporting an unequivocal plateau in .VO2 during incremental exercise. PURPOSE: The purpose of this investigation was to test the hypothesis that there is no significant difference between the .VO2max obtained during incremental exercise and a subsequent supramaximal exercise test in competitive middle-distance runners. We sought to determine conclusively whether .VO2 attains a maximal value that subsequently plateaus or decreases with further increases in exercise intensity. METHODS: Fifty-two subjects (36 men, 16 women) performed three series of incremental exercise tests while measuring .VO2 using the Douglas bag method. On the day after each incremental test, the subjects returned for a supramaximal test, during which they ran at 8% grade with the speed chosen individually to exhaust the subject between 2 and 4 min. .VO2 at supramaximal exercise intensities (30% above incremental .VO2max) was measured continuously. RESULTS: .VO2max measured during the incremental test (63.3 +/- 6.3 mL.kg(-1).min(-1); mean +/- SD) was indistinguishable from the .VO2max during the supramaximal test (62.9 +/- 6.2, N = 156; P = 0.77) despite a sufficient duration of exercise to demonstrate a plateau in .VO2 during continuous supramaximal exercise. These data provide strong support for the hypothesis that there is indeed a peak and subsequent plateau in .VO2 during maximal exercise intensity. CONCLUSIONS: .VO2max is a valid index measuring the limits of the cardiorespiratory systems' ability to transport oxygen from the air to the tissues at a given level of physical conditioning and oxygen availability.

Walking may be related to less vascular stiffness in the Activity Counseling Trial (ACT).

BACKGROUND: The ACT was a clinical trial of various patient education and counseling interventions to increase physical activity in sedentary primary care populations. It provided the opportunity to measure the effect of increasing physical activity on aortic pulse wave velocity (APWV), a measure of vascular stiffness, in a relatively healthy middle-aged population. The effects of the interventions, as well as the impact of walking and correlates such as older age and maximal oxygen uptake (VO2max), on APWV were assessed. METHODS: The participants in this study were a subset of the 874 persons recruited for the ACT. Information about self-reported physical activity and disease status was collected at baseline (464 persons), 6-month (528 persons), and 24-month (555 persons) intervals. Physiological measures included APWV, systolic blood pressure, and other correlates. RESULTS: In multivariate analyses, the various treatment arms did not have a significant effect on APWV. However, walking in hours per day was associated with slower APWV times or less stiffness (P = .03). This was significant for women and consistent but not significant for men. In addition, age, clinic site, race, systolic blood pressure, and VO2max were independently associated with APWV. CONCLUSIONS: Increased walking frequency over a 24-month period was predictive of reduced vascular stiffness in ACT. The more significant result for walking frequency in women than in men might be caused by the presence of a low Vo2max or physical activity threshold for an effect of walking on APWV, which most women achieved but most men had surpassed at the start of the study. Although needing confirmation because this was a secondary analysis, modest physical activity may have a beneficial effect on large vessel structure.

Regional body fat distribution in HIV-infected patients with lipodystrophy.

BACKGROUND: Objective criteria for the assessment of patients with lipodystrophy syndrome in human immunodeficiency virus infection (LDHIV) have not emerged. METHODS: We compared regional body fat changes in 13 men with severe LDHIV on protease inhibitor-inclusive antiretroviral therapy with 13 control HIV-infected men using anthropometry, dual-energy X-ray absorptiometry (DEXA), and whole-body magnetic resonance imaging (MRI). RESULTS: LDHIV patients, compared with control subjects, had thinner gluteal, suprailiac, and triceps skinfolds (p < .01) and increased waist circumference (98 +/- 5 cm vs 86 +/- 9 cm, respectively; p = .0008). DEXA studies revealed reduced lower extremity fat (12 +/- 5% vs 22 +/- 9%; p = .0006), increased head and neck fat (18 +/- 3% vs 16 +/- 1%; p = .01), and increased proportion of total body fat in the trunk (65 +/- 7% vs 53 +/- 8%; p = .0005). MRI analysis revealed reduced thigh fat (12 +/- 5% vs 22 +/- 12%; p = .01), increased dorsocervical fat depth (47 +/- 24 mm vs 19 +/- 7 mm; p = .0009), and nearly significant increase in intra-abdominal fat (218 +/- 90 cm2 vs 157 +/- 70 cm2; p = .057). Interestingly, control subjects showed a positive relationship between intra-abdominal and dorsocervical fat (r= .57, p = .04), but the LDHIV patients showed a negative relationship (r= -.55, p = .05), suggesting a novel split phenotype among LDHIV patients of either dorsocervical or intra-abdominal fat accumulation. CONCLUSIONS: We conclude that MRI provides the best tools for definition of LDHIV syndrome and reveals variable phenotypes among LDHIV patients.