Sex differences in ventricular-vascular coupling following endurance training.

INTRODUCTION: Ventricular and vascular coupling is defined as the ratio of arterial elastance (Ea) to ventricular elastance (Elv) and describes the interaction between the heart and arterial system. There are sex differences in both arterial and ventricular function in response to both acute exercise and aerobic exercise training. PURPOSE: To examine the effects of aerobic exercise training on elastances and the coupling ratio in young adult men and women. We hypothesized a reduction in the coupling ratio in both sexes due to a decrease in Ea that would be more pronounced in men and an increase in Elv that would be larger in women. METHODS: Fifty-three healthy, young adults completed the study. Central pulse wave velocity and heart volumes were measured before and after an 8-week aerobic training intervention. Elastances were calculated as Ea = end-systolic pressure/stroke volume and Elv = end-systolic pressure/end-systolic volume and indexed to body surface area. RESULTS: After the intervention, women augmented indexed and un-indexed Elv from 2.09 ± 0.61 to 2.52 ± 0.80 mmHg/ml, p < 0.05, and reduced the coupling ratio from 0.72 ± 18 to 0.62 ± 15, p < 0.05, while men maintained their pre-training ratio (from 0.66 ± 0.20 to 0.74 ± 0.21, p > 0.05). Women also reduced end-systolic pressure (from 91 ± 10 to 87 ± 10 mmHg), and both groups reduced central pulse wave velocity (from 6.0 ± 1.0 to 5.6 ± 0.6 m/s, p < 0.05). CONCLUSION: We conclude that after 8 weeks of aerobic training, only women reduced their coupling ratio due to an increase in Elv. This suggests that aerobic exercise training elicits sex-dependent changes in the coupling ratio in young, healthy individuals.

Effect of sex on wasted left ventricular effort following maximal exercise.

Wasted left ventricular effort (∆Ew) refers to work required of the left ventricle to eject blood that does not result in increased stroke volume and is related to left ventricular hypertrophy. Literature shows that men and women have differing ventricular and vascular responses to and following exercise. Our purpose was to determine how ∆Ew changes post-exercise in men and women and examine potential mechanisms. We hypothesized a reduction in ∆Ew that would be greater in men and that central pulse wave velocity and wave intensity (WIA) would be related to ∆Ew. Blood pressures, central pulse wave velocity (cPWV), and WIA were obtained at rest, 15 and 30 min after maximal exercise. Both sexes reduced ∆Ew post-maximal exercise (p>0.05 for interaction), but women had higher ∆Ew at each time point (p<0.05). The first peak of WIA increased 15 min post-exercise only in women (p<0.05). cPWV was attenuated (p<0.05) in women at 15 min and men at 30 min (p<0.05) post-exercise with a significant time by sex interaction (p<0.05). WIA (1st peak) was correlated (p<0.05) to ∆Ew in both sexes before and 15 min post-exercise, but cPWV was only associated with ∆Ew in men at 30 min post-exercise. We conclude that both sexes decrease ∆Ew after maximal exercise, but vascular and ventricular changes associated with the attenuation of ∆Ew are not uniform between sexes.

Intake of New Zealand Blackcurrant Powder Affects Skin-Borne Volatile Organic Compounds in Middle-Aged and Older Adults.

Skin volatile organic compounds (VOCs) can cause body odor or reveal human disease and may result from lipid peroxidation or activity by skin bacteria. We examined the effect of intake of New Zealand blackcurrant (NZBC) powder for 77 skin VOCs in middle-aged and older adults in a crossover design. Fourteen adults (nine males, age: 55 ± 5 yrs) consumed NZBC powder for 7 days (6 g·day-1 with 138.6 mg anthocyanins). Two hours after the last intake, a passive flux sampler with trapping media was applied in the base of the neck for 1 hour. Gas chromatography-mass spectrometry was used for media analysis. Habitual anthocyanin intake was quantified using a food frequency questionnaire. Compared to control (i.e., no intake of NZBC powder), emission of six skin VOCs (i.e., 2-nonenal, acetic acid, 2-hexanone, 6-methyl-5-hepten-2-one, benzaldehyde, allyl methyl sulfide) were lower by more than 25%. Increases were observed for γ-octanolactone (+184%) and γ-decanolactone (+89%). A trend for a decrease for isovaleraldehyde, hexanal, and 2-pentanone, and an increase for heptanoic acid and γ-nonanolactone was observed. There was a significant correlation with daily habitual dietary anthocyanin intake for control values of hexanal and percentage change of γ-octanolactone. NZBC powder can change emanation of some VOCs in human skin. Analysis of skin VOCs following specific polyphenol intake may address the impact of dietary components to affect internal metabolic processes, body odor, and health.

Passive immunization against tumor necrosis factor and interleukin-1 fails to reduce lung neutrophil sequestration in chronic sepsis.

The proinflammatory cytokines tumor necrosis factor (TNF) and interleukin-1 (IL-1) are produced within the lung during sepsis, and may induce neutrophil sequestration resulting in neutrophil-mediated lung injury. We hypothesized that, if there is a cause and effect between TNF alpha or IL-1 production and lung neutrophil sequestration during chronic sepsis, TNF alpha mRNA and IL-1 mRNA levels in the lung after cecal ligation and puncture should correlate with the number of sequestered neutrophils as measured by the myeloperoxidase (MPO) content of the lung. To test this hypothesis, Swiss Webster mice were subjected to varying degrees of infectious challenge by single and double-puncture cecal ligation and puncture, or simultaneous antibiotic treatment, and their lungs and blood were harvested at 24 h. Lung TNF alpha and IL-1 beta mRNAs were measured by the reverse-transcription differential polymerase chain reaction, and MPO was measured by colorimetric assay. TNF alpha serum levels showed no correlation with the MPO content of the lung, whereas IL-1 levels were undetectable. Lung TNF alpha mRNA correlated weakly, and IL-1 beta mRNA exhibited a strong correlation with lung MPO (r = .9, p < .01), but administration of anti-TNF alpha- or anti-IL-1-neutralizing antibodies did not prevent a rise in lung MPO. IL-1 beta mRNA in bronchoalveolar macrophages correlated well with whole lung tissue IL-1 beta mRNA levels (r = .91, p < .01).(ABSTRACT TRUNCATED AT 250 WORDS)

Health and demographic characteristics of respondents in an Australian national sexuality survey: comparison with population norms.

STUDY OBJECTIVE: To assess the representativeness of survey participants by systematically comparing volunteers in a national health and sexuality survey with the Australian population in terms of self reported health status (including the SF-36) and a wide range of demographic characteristics. DESIGN: A cross sectional sample of Australian residents were compared with demographic data from the 1996 Australian census and health data from the 1995 National Health Survey. SETTING: The Australian population. PARTICIPANTS: A stratified random sample of adults aged 18-59 years drawn from the Australian electoral roll, a compulsory register of voters. Interviews were completed with 1784 people, representing 40% of those initially selected (58% of those for whom a valid telephone number could be located). MAIN RESULTS: Participants were of similar age and sex to the national population. Consistent with prior research, respondents had higher socioeconomic status, more education, were more likely to be employed, and less likely to be immigrants. The prevalence estimates, means, and variances of self reported mental and physical health measures (for example, SF-36 subscales, women's health indicators, current smoking status) were similar to population norms. CONCLUSIONS: These findings considerably strengthen inferences about the representativeness of data on health status from volunteer samples used in health and sexuality surveys.

Effect of resistance training on biomarkers of vascular function and oxidative stress in young African-American and Caucasian men.

African Americans (AA) have an earlier onset of hypertension and a different vascular profile than their Caucasian (Cau) peers. Research suggests that biological mediators of vascular inflammation are different among these groups in hypertensive populations. Resistance training (RT) is an important exercise modality that improves the vascular profile of young AA men. We examined the role of RT on biomarkers of vascular function and oxidative stress in body mass index-matched AA and Cau men. RT for 6 weeks elicited significant changes in circulating matrix metalloprotease-9 (MMP-9) and 8-Isoprostane (8-IsoP) in young AA men (n=14, AA; n=18, Cau; 18-35 years). MMP-9 was lower and decreased in AA (pre: P=0.02; post: P<0.001) and a time × group interaction for MMP-9 (F(1, 30)=4.81; P=0.036) and 8-IsoP (F(1, 24)=7.09; P=0.014) was detected. 8-IsoP decreased in AA (P=0.026) but did not change in Cau (P=0.309). Notably, the increase in strength (1-repetition maximum (1-RM)) was correlated with the decrease in MMP-9 (r=-0.398; P=0.022). Furthermore, these adaptations were independent of any improvement in cardiorespiratory fitness. We demonstrate that RT effectively reduces matrix remodeling proteins and oxidative stress in young AA men. Increasing strength may be beneficial for improving vascular health and offsetting novel cardiovascular risk factors of hypertension in young AA men.

Micturition patterns in patients paraplegic following spinal cord injury.

Patterns of micturition in normal subjects and in patients after complete and incomplete injury of the spinal cord have been compared. All patients showed an abnormal flow pattern, this being least obvious in those who had undergone resection of the bladder neck and external sphincter. It is suggested that the Disa type 14 F 45 mictiograph is a useful instrument in determining the need for transurethral resection following spinal cord injury.

Angiotensin II receptor subtypes on adrenal adenoma in primary hyperaldosteronism.

Patients with an aldosterone-producing adenoma (APA) characteristically fail to show an increase in plasma aldosterone (PA) concentration with maneuvers that increase angiotensin II (Ang II), yet they retain a brisk response of PA to adrenocorticotrophic hormone. Therefore, adrenal Ang II receptor binding was characterized in a patient with APA who had a blocked PA response to Ang II infusion before adrenalectomy. The binding of [125I]Sar1,IIe5-Ang II in adrenal gland and tumor was fully displaced by excess Ang II. In the tumor, 98% of [125I]Sar1,IIe5-Ang II binding was displaced by the AT, receptor antagonist losartan, yet only 5% was displaced by the AT2 receptor antagonist PD-123,319. Autoradiography of the adrenal gland itself showed a predominance of AT1 receptors in the cortex and AT2 receptors in the medulla. The tumor showed a predominance of AT1 receptors, but there was some evidence of a limited population of AT2 receptors. The tumor and adjacent adrenal contained high concentrations of Ang II. In conclusion, a defect in Ang II-stimulated aldosterone secretion in APA occurs despite high concentrations of Ang II in the adrenal and the presence of specific, high-affinity Ang II receptor binding sites.

Dialysis is not indicated immediately after administration of nonionic contrast agents in patients with end-stage renal disease treated by maintenance dialysis.

OBJECTIVE: This study was undertaken to determine the necessity of immediate dialysis after intravascular injection of contrast material in patients with end-stage renal disease who are being maintained on hemodialysis. Although many physicians support this practice, we could find no reports of studies to confirm or refute its necessity. SUBJECTS AND METHODS: We studied 10 patients being treated with hemodialysis who were undergoing 11 diagnostic procedures that required intravascular contrast material. The patients received 40-225 ml of nonionic contrast material and were followed up with clinical examination and laboratory analysis to determine any adverse effects from contrast administration or the need for dialysis or both. RESULTS: No significant changes in blood pressure, ECG, total serum protein level of osmolality, extracellular fluid volume, or body weight occurred after injection of contrast material. None of the patients had clinical features that necessitated emergent dialysis. CONCLUSION: We conclude that nonionic contrast material can be given safely to patients with end-stage renal disease who are being maintained on hemodialysis. Immediate postprocedural dialysis is unwarranted as a routine practice.