Oligomethylene-bridged dinuclear triorganotin triflates and diphenylphosphinates. Ion pairing in the solid state and electrolytic dissociation in solution of [Ph2Sn(CH2)nSnPh2X](O3SCF3) (X = OH, O2PPh2; n = 1-3)

The condensation of [Ph₂(OH)Sn(CH₂)<i>_ni>Sn(OH)Ph₂] (1-3; <i>ni> = 1-3) with HO₃SCF₃ and HO₂PPh₂ provided [Ph₂Sn(CH₂)_<i>ni>SnPh₂(OH)](O₃SCF₃) (4-6; <i>ni> = 1-3) and [Ph₂(O₂PPh₂)Sn(CH₂)_<i>ni>Sn(O₂PPh₂)Ph₂] (10-12; <i>ni> = 1-3), respectively. The reaction of [Ph₂Sn(CH₂)_<i>ni>SnPh₂(OH)](O₃SCF₃) (4-6; <i>ni> = 1-3) with HO₂PPh₂ and NaO₂PPh₂ gave rise to the formation of [Ph₂Sn(CH₂)_<i>ni>SnPh₂(O₂PPh₂)](O₃SCF₃) (7-9; <i>ni> = 1-3) and [Ph₂(OH)Sn(CH₂)_<i>ni>Sn(O₂PPh₂)Ph₂] (13-15; _<i>ni> = 1-3), respectively. In the solid state, compounds 4-9 comprise ion pairs of cationic cyclo-[Ph₂SnCH₂SnPh₂(OH)]₂²⁺, cyclo-[Ph₂Sn(CH₂)<i>_ni>SnPh₂(OH)]⁺ (<i>ni> = 2, 3), and cyclo-[Ph₂Sn(CH₂)_<i>ni>SnPh₂(O₂PPh₂)]⁺ (<i>ni> = 1-3) and triflate anions. In MeCN, the eight-membered-ring system cyclo-[Ph₂SnCH₂SnPh₂(OH)]₂²⁺ appears to be in equilibrium with the four-membered-ring system cyclo-[Ph₂SnCH₂SnPh₂(OH)]⁺. In contrast, compounds 10-15 show no ionic character. Compounds 1-15 were characterized by multinuclear NMR spectroscopy in solution and in the solid state, IR spectroscopy, conductivity measurements, electrospray mass spectrometry, osmometric molecular weight determinations, and X-ray crystallography (4, 5, 7, and 12).

The effects of short-term sprint training on MCT expression in moderately endurance-trained runners

The purpose of this study was to assess the effects of short-term sprint training on transient changes in monocarboxylate lactate transporter 1 (MCT1) and MCT4 protein and mRNA content. Seven moderately endurance-trained runners (mean ± SE; age 27.7±2.9 years, body mass 81.1±5.9 kg, <i>VOi>₂ max 58.1±2.0 ml kg^&minus;1 min^&minus;1) completed a <i>VOi>₂ max and a supramaximal running test to exhaustion (RTE) before and after a 6-week period of sprint training. The sprint training was progressive and consisted of 18 sessions of near maximal short duration (5–15 s) sprints to compliment the athlete’s endurance training. Prior to the training period there was a significant (<i>Pi><0.05) increase in MCT1, but not MCT4 protein, 2 h after the RTE. This occurred without any change in corresponding mRNA levels. After the training period, there was a significant increase in MCT1 protein but no significant change in the MCT4 isoform. Both MCT1 and MCT4 mRNA was significantly lower at rest and 2 h post-RTE after the completion of the training period. After the training period, there was a significant increase in the time to exhaustion and distance covered during the RTE. This study demonstrates that sprint training of this length and type results in an upregulation of MCT1 protein, but not MCT4 content. Additionally, this study shows conflicting adaptations in MCT1 and MCT4 protein and mRNA levels following training, which may indicate post-transcriptional regulation of MCT expression in human muscle.

Effect of glycerol-induced hyperhydration on thermoregulation and metabolism during exercise in the heat

This study examined the effect of glycerol ingestion on fluid homeostasis, thermoregulation, and metabolism during rest and exercise. Six endurance-trained men ingested either 1 g glycerol in 20 ml H₂O.kg^-1 body weight (bw) (GLY) or 20 ml H₂O.kg^-1bw (CON) in a randomized double-blind fashion, 120 min prior to undertaking 90 min of steady state cycle exercise (SS) at 98 % of lactate threshold in dry heat (35 degrees C, 30 % RH), with ingestion of CHO-electrolyte beverage (6 % CHO) at 15-min intervals. A 15-min cycle, where performance was quantified in kJ, followed (PC). Pre-exercise urine volume was lower in GLY than CON (1119 ± 97 vs. 1503 ± 146 ml&middot; 120 min^-1;<i> pi> < .05). Heart rate was lower (<i>pi> < .05) throughout SS in GLY, while forearm blood flow was higher (17.1 ± 1.5 vs. 13.7 ± 3.0 ml.100 g tissue&middot;min^-1; <i>pi> < .05) and rectal  temperature lower (38.7 ± 0.1 vs. 39.1 ± 0.1 ° C; <i>pi> < .05) in GLY late in SS. Despite these changes, skin and muscle temperatures and circulating catecholamines were not different between trials. Accordingly, no differences were observed in muscle glycogenolysis, lactate accumulation, adenine nucleotide, and phosphocreatine degradation or inosine 5'-monophosphate accumulation when comparing GLY with CON. Of note, the work performed during PC was 5 % greater in GLY (252 ± 10 vs. 240 ± 9 kJ; <i>pi> < .05). These results demonstrate that glycerol, when ingested with a bolus of water 2 hours prior to exercise, results in fluid retention, which is capable of reducing cardiovascular strain and enhancing thermoregulation. Furthermore, this practice increases exercise performance in the heat by mechanisms other than alterations in muscle metabolism.

Home-based resistance training is not sufficient to maintain improved glycemic control following supervised training in older individuals with type 2 diabetes

OBJECTIVE—To examine whether improvements in glycemic control and body composition resulting from 6 months of supervised high-intensity progressive resistance training could be maintained after an additional 6 months of home-based resistance training.

RESEARCH DESIGN AND METHODS—We performed a 12-month randomized controlled trial in 36 sedentary, overweight men and women with type 2 diabetes (aged 60–80 years) who were randomly assigned to moderate weight loss plus high-intensity progressive resistance training (RT&WL group) or moderate weight loss plus a control program (WL group). Supervised gymnasium-based training for 6 months was followed by an additional 6 months of home-based training. Glycemic control (HbA_1c), body composition, muscle strength, and metabolic syndrome abnormalities were assessed at 0, 3, 6, 9, and 12 months.

RESULTS—Compared with the WL group, HbA_1c decreased significantly more in the RT&WL group (–0.8%) during 6 months of supervised gymnasium-based training; however, this effect was not maintained after an additional 6 months of home-based training. In contrast, the greater increase in lean body mass (LBM) observed in the RT&WL group compared with the WL group (0.9 kg, <i>Pi> < 0.05) after the gymnasium-based training tended to be maintained after the home-based training (0.8 kg, <i>Pi> = 0.08). Similarly, the gymnasium-based increases in upper body and lower body muscle strength in the RT&WL group were maintained over the 12 months (<i>Pi> < 0.001). There were no between-group differences for changes in body weight, fat mass, fasting glucose, or insulin at 6 or 12 months.

CONCLUSIONS—In older adults with type 2 diabetes, home-based progressive resistance training was effective for maintaining the gymnasium-based improvements in muscle strength and LBM but not glycemic control. Reductions in adherence and exercise training volume and intensity seem to impede the effectiveness of home-based training for maintaining improved glycemic control.

The effect of school suspensions and arrests on subsequent adolescent antisocial behavior in Australia and the United States

Purpose: To examine the effect of school suspensions and arrests (i.e., being taken into police custody) on subsequent adolescent antisocial behavior such as violence and crime, after controlling for established risk and protective factors in Victoria, Australia and Washington State, United States (U.S.). Methods: This article reports on analyses of two points of data collected 1 year apart within a cross-national longitudinal study of the development of antisocial behavior, substance use, and related behaviors in approximately 4000 students aged 12 to 16 years in Victoria, Australia and Washington State, U.S. Students completed a modified version of the Communities That Care self-report survey of behavior, as well as risk and protective factors across five domains (individual, family, peer, school, and community). Multivariate logistic regression analyses investigate the effect of school suspensions and arrests on subsequent antisocial behavior, holding constant individual, family, peer, school, and community level influences such as being female, student belief in the moral order, emotional control, and attachment to mother. Results: At the first assessment, school suspensions and arrests were more commonly reported in Washington, and school suspensions significantly increased the likelihood of antisocial behavior 12 months later, after holding constant established risk and protective factors (adjusted odds ratio [OR] 1.5, 95% confidence interval [CI] 1.1–2.1, <i>_pi> < .05). Predictors of antisocial behavior spanned risk and protective factors across five individual and ecological areas of risk. Risk factors in this study were pre-existing antisocial behavior (OR 3.6, CI 2.7–4.7,_{<i> pi>} < .001), association with antisocial peers (OR 1.8, CI 1.4–2.4, _<i>pi> < .001), academic failure (OR 1.3, CI 1.1–1.5, _<i>pi> < .01), and perceived availability of drugs in the community (OR 1.3, CI 1.1–1.5, <i>_pi> < .001). Protective factors included being female (OR 0.7, CI 0.5–0.9, _<i>pi> < .01), student belief in the moral order (OR 0.8, CI 0.6–1.0, p < .05), student emotional control (OR 0.7, CI 0.6–0.8, _<i>pi> < .001), and attachment to mother (OR 0.8, CI 0.7–1.0, _<i>pi> < .05). Conclusions:  School suspensions may increase the likelihood of future antisocial behavior. Further research is required to both replicate this finding and establish the mechanisms by which school suspensions exert their effects.

Therapist-assisted, internet-based treatment for panic disorder: can general practitioners achieve comparable patient outcomes to psychologists

Background: Mental illness is an escalating concern worldwide. The management of disorders such as anxiety and depression largely falls to family doctors or general practitioners (GPs). However, GPs are often too time constrained and may lack the necessary training to adequately manage the needs of such patients. Evidence-based Internet interventions represent a potentially valuable resource to reduce the burden of care and the cost of managing mental health disorders within primary care settings and, at the same time, improve patient outcomes.
Objective: The present study sought to extend the efficacy of a therapist-assisted Internet treatment program for panic disorder, Panic Online, by determining whether comparable outcomes could be achieved and maintained when Panic Online was supported by either GPs or psychologists.
Methods: Via a natural groups design, 96 people with a primary diagnosis of panic disorder (with or without agoraphobia) completed the Panic Online program over 12 weeks with the therapeutic assistance of their GP (<i>ni> = 53), who had received specialist training in cognitive behavioral therapy, or a clinical psychologist (<i>ni> = 43). Participants completed a clinical diagnostic telephone interview, conducted by a psychologist, and a set of online questionnaires to assess panic-related symptoms at three time periods (pretreatment, posttreatment, and 6 month follow-up).
Results: Both treatments led to clinically significant improvements on measures of panic and panic-related symptomatology from pretreatment to posttreatment. Both groups were shown to significantly improve over time. Improvements for both groups were maintained at follow-up; however, the groups did differ significantly on two quality of life domains: physical (F₁,₈₂ = 9.13, <i>Pi> = .00) and environmental (F₁,₈₂ = 4.41, <i>Pi> = .04). The attrition rate was significantly higher among those being treated by their GP (&chi;²₁ = 4.40, <i>Pi> = .02, N = 96).
Conclusions: This study provides evidence that Internet-based interventions are an effective adjunct to existing mental health care systems. Consequently, this may facilitate and enhance the delivery of evidence-based mental health treatments to increasingly large segments of the population via primary care systems and through suitably trained health professionals.