The kinetics of cardiac troponin T release during and after 1- and 6-h maximal cycling trials.

Objectives: In this study, the effects of short-duration high-intensity exercise and long-duration exercise on high-sensitivity cardiac troponin T (hs-cTnT) levels were compared.

Methods: Twelve male amateur cyclists performed 1- and 6-h cycling trials. In both exercise trials, hs-cTnT was assessed at rest, immediately postexercise and at 1, 3, 6, 12, and 24 h postexercise.

Characterization of Different Forms of Kava (Piper methysticum) Products by UPLC-MS/MS.

There are several forms of kava () products available for human consumption, and many factors are known to influence their chemical compositions and therefore their pharmacological properties. Because of the increased popularity of kava intake, a rigorous characterization of their content diversity is prerequisite, particularly due to its known potential to cause hepatotoxicity. To understand the composition diversity of kavalactones and flavokavains in commercial kava products, we developed a UPLC-MS/MS-based analytical method for the quantification of six kavalactones (kavain, dihydrokavain, methysticin, dihydromethysticin, yangonin and desmethoxyyangonin) and two flavokavains (flavokavains A and B) and analyzed their contents in 28 different kava products in the form of capsules, tinctures, traditional aqueous suspensions and dried powders.

COVID-19 and ethnicity: Does reduced responsiveness to glucocorticoids explain the more aggressive nature of disease among minorities?

Marked ethnic variations in complications and mortality have been noted following infection with COVID-19, with Black, Asian, and minority ethnic groups (BAME) being particularly hard hit. We hypothesise that glucocorticoid resistance stemming from several intrinsic reasons such as chronic social stress and lower circulating levels of Vitamin D may contribute to the exaggerated inflammatory response, more severe disease and poorer outcomes observed in BAME.

Kava as a Clinical Nutrient: Promises and Challenges.

Kava beverages are typically prepared from the root of Piper methysticum. They have been consumed among Pacific Islanders for centuries. Kava extract preparations were once used as herbal drugs to treat anxiety in Europe.

Oral Dosing of Dihydromethysticin Ahead of Tobacco Carcinogen NNK Effectively Prevents Lung Tumorigenesis in A/J Mice.

Our early studies demonstrated an impressive chemopreventive efficacy of dihydromethysticin (DHM), unique in kava, against tobacco carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced lung tumorigenesis in A/J mice in which DHM was supplemented in the diet. The current work was carried out to validate the efficacy, optimize the dosing schedule, and further elucidate the mechanisms using oral bolus dosing of DHM. The results demonstrated a dose-dependent chemopreventive efficacy of DHM (orally administered 1 h before each of the two NNK intraperitoneal injections, 1 week apart) against NNK-induced lung adenoma formation.

Design, synthesis, and enzymatic characterization of quinazoline-based CYP1A2 inhibitors.

Cytochrome P450 isozyme 1A2 (CYP1A2) is one main xenobiotic metabolizing enzyme in humans. It has been associated with the bioactivation of procarcinogens, including 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), a tobacco specific and potent pulmonary carcinogen. This work describes the computational design and in-silico screening of potential CYP1A2 inhibitors, their chemical synthesis, and enzymatic characterization with the ultimate aim of assessing their potential as cancer chemopreventive agents.

Kava and its Kavalactones Inhibit Norepinephrine-induced Intracellular Calcium Influx in Lung Cancer Cells.

Kava, the extract of the roots of , has been traditionally consumed in the South Pacific islands for its natural relaxing property. Epidemiological data suggests that kava consumption may reduce human cancer risk, and and models suggest chemopreventive potential against carcinogen-induced tumorigenesis. Therefore, knowledge about its molecular mechanisms and responsible ingredient(s) for these beneficial properties will better guide kava's use for the management of these disorders.

11β-hydroxysteroid dehydrogenase type-II activity is affected by grapefruit juice and intense muscular work.

Objective: The enzymatic activity of 11β-hydroxysteroid dehydrogenase-2 (11β-HSD2) is key to protecting mineral corticoid receptors from cortisol and has been implicated in blood pressure regulation. Grapefruit juice (GFJ) and acidity are thought to inhibit this enzyme in vitro. This study examines the effect of GFJ and intense exercise on 11β-HSD2 enzyme activity in vivo.

Dietary adherence during weight loss predicts weight regain.

This study examined the relationship between previous dietary adherence during a low-calorie diet weight loss intervention and subsequent weight change during a 2-year follow-up for weight maintenance. One hundred and sixteen healthy, recently weight reduced (lost ~12 kg, BMI 22-25 kg/m2) premenopausal women were studied. Dietary adherence was assessed by doubly labeled water (DLW) and body composition change.

Age, muscle fatigue, and walking endurance in pre-menopausal women.

Aging is associated with loss of endurance; however, aging is also associated with decreased fatigue during maximal isometric contractions. The aims of this study were to examine the relationship between age and walking endurance (WE) and maximal isometric fatigue (MIF) and to determine which metabolic/fitness components explain the expected age effects on WE and MIF. Subjects were 96 pre-menopausal women.

Exercise training prevents regain of visceral fat for 1 year following weight loss.

The purpose of this study was to determine what effect aerobic and resistance exercise training has on gain of visceral fat during the year following weight loss. After being randomly assigned to aerobic training, resistance training, or no exercise training, 45 European-American (EA) and 52 African-American (AA) women lost 12.3 +/- 2.

Effect of dietary adherence with or without exercise on weight loss: a mechanistic approach to a global problem.

Context: Weight loss using low-calorie diets produces variable results, presumably due to a wide range of energy deficits and low-dietary adherence.

Objective: Our objective was to quantify the relationship between dietary adherence, weight loss, and severity of caloric restriction.

Design And Setting: Participants were randomized to diet only, diet-endurance training, or diet-resistance training until body mass index (BMI) was less than 25 kg/m(2).

Translating exercise biology into the Venezuelan medical education and health care system.

In the absence of pharmacological agents, physical exercise was widely used by physicians in the late 19th century to treat a number of maladies. In the 1950's, epidemiological evidence suggested an association between physical activity and health, and increased interest in clinical exercise biology. By the 1990's, sufficient research data was accumulated on the benefits of exercise, such that North American medical associations, government agencies, and the World Health Organization have published guidelines on exercise for public and clinical populations.

Discordant localization of 2-[18F]-fluoro-2-deoxy-D-glucose in 6-[18F]-fluorodopamine- and [(123)I]-metaiodobenzylguanidine-negative metastatic pheochromocytoma sites.

Background: Although the majority of pheochromocytomas (PHEO) are benign, a subset is malignant. Computed tomography (CT) and magnetic resonance imaging (MRI) localize PHEO with high sensitivity but, because of limited specificity, [(131)I]- or [(123)I]-metaiodobenzylguanidine ([(131)I]- or [(123)I]-MIBG) is often used as a complementary agent. 6-[18F]-fluorodopamine ([18F]-DA) has been developed as a radiopharmaceutical for the targeting of noradrenergic pathways, and has been shown to result in a better detection rate of PHEO sites than MIBG; however, [18F]-DA has shown a lack of accumulation in some patients with metastatic PHEO.