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Background and Objectives: The past 10 years' wave of syphilis epidemics has challenged syphilis control programs. Although apparently connected to drugs-for-sex trading of crack cocaine, the genesis and resolution of these epidemics is poorly understood.Goals Of the Study: The goals of this study were to develop a mathematical model of epidemic syphilis transmission based on empiric data, to stimulate and ascertain behavioral and sociologic features necessary to produce epidemic transmission, and to explore mechanisms leading to resolution of epidemic transmission.Study Design: The study used multi-compartment iterative computer simulation using empirically derived input data.Results: Epidemic transmission resulted from adding a small core group of individuals with very high levels of partner exchange (300-400 partners per year) to a population with levels of partner exchange seen in the general population. Epidemic resolution could result from immunity or subtle changes in the size or partner exchange rate of the core group.Conclusion: There is a need for sexually transmitted disease control programs to reevaluate their approach to prevention and control of epidemic syphilis in light of data on transmission dynamics. [ABSTRACT FROM AUTHOR]

This article describes the development and technical adequacy of the Classroom Observations of Student Teacher Interactions (COSTI) instrument, a tool for measuring the frequency and rate of explicit instructional interactions, such as those used in Direct Instruction curricula, for teaching children basic reading and math skills. COSTI was originally developed to provide teachers with coaching feedback to improve their explicit reading instructional practices , and has been shown in multiple studies to be a reliable and valid predictor of student gains in beginning reading and math skills. This article discusses potential uses of the instrument for training and coaching across curricula with varying instructional design features, and lays out a future research agenda to further improve COSTI and related observation tools for studying explicit instructional practices and their contribution to student learning., Competing Interests: Conflict of InterestThe authors declare that they have no conflicts of interest., (© Association for Behavior Analysis International 2021.)

Investigate the underlying cellular basis of muscle atrophy (Placebo) and atrophy reduction (essential amino acid supplementation, EAAs) in total knee arthroplasty (TKA) patients by examining satellite cells and other key histological markers of inflammation, recovery, and fibrosis. Forty-one subjects (53-76 yr) scheduled for TKA were randomized into two groups, ingesting 20 g of EAAs or placebo, twice-daily, for 7 days before TKA and for 6 wk after surgery. A first set of muscle biopsies was obtained from both legs before surgery in the operating room, and patients were randomly assigned and equally allocated to have two additional biopsies at either 1 or 2 wk after surgery. Biopsies were processed for gene expression and immunohistochemistry. Satellite cells were significantly higher in patients ingesting 20 g of essential amino acids twice daily for the 7 days leading up to surgery compared with Placebo (operative leg P = 0.03 for satellite cells/fiber and P = 0.05 for satellite cell proportions for Type I-associated cells and P = 0.05 for satellite cells/fiber for Type II-associated cells.) Myogenic regulatory factor gene expression was different between groups, with the Placebo Group having elevated MyoD expression at 1 wk and EAAs having elevated myogenin expression at 1 wk. M1 macrophages were more prevalent in Placebo than the EAAs Group. IL-6 and TNF-α transcripts were elevated postsurgery in both groups; however, TNF-α declined by 2 wk in the EAAs Group. EAAs starting 7 days before surgery increased satellite cells on the day of surgery and promoted a more favorable inflammatory environment postsurgery. NEW & NOTEWORTHY Clinical studies by our group indicate that the majority of muscle atrophy after total knee arthroplasty (TKA) in older adults occurs rapidly, within the first 2 wks. We have also shown that essential amino acid supplementation (EAAs) before and after TKA mitigates muscle atrophy; however, the mechanisms are unknown. These results suggest that satellite cell numbers are elevated with EAA ingestion before surgery, and after surgery, EAA ingestion positively influences markers of inflammation. Combined, these data may help inform further studies designed to address the accelerated sarcopenia that occurs in older adults after major surgery.

Background: Substantial muscle atrophy occurs after total knee arthroplasty (TKA), resulting in decreased strength and impaired mobility. We sought to determine whether perioperative supplementation with essential amino acids (EAA) would attenuate muscle atrophy following TKA and whether the supplements were safe for ingestion in an older surgical population., Methods: We performed a double-blind, placebo-controlled, randomized trial of 39 adults (age range, 53 to 76 years) undergoing primary unilateral TKA who ingested 20 g of EAA (n = 19) or placebo (n = 20) twice daily for 7 days preoperatively and for 6 weeks postoperatively. At baseline and 6 weeks postoperatively, magnetic resonance imaging (MRI) scans were obtained to measure quadriceps and hamstrings muscle volume. Secondary outcomes included functional mobility and strength. Data on physical activity, diet, and patient-reported outcomes (Veterans RAND 12-Item Health Survey and Knee injury and Osteoarthritis Outcome Score) were collected. Safety was determined through blood tests evaluating blood urea nitrogen, creatinine, creatinine clearance, homocysteine, and renal and liver function. Laboratory values at baseline, on the day of surgery, and at 2 days, 2 weeks, and 6 weeks postoperatively were compared between treatment groups. Analysis of covariance models, with baseline values as covariates, were used to evaluate outcomes between treatment groups. P values were adjusted for multiple tests., Results: Compared with baseline, the EAA group had significantly less decrease in mean quadriceps muscle volume compared with the placebo group in the involved leg (-8.5% ± 2.5% compared with -13.4% ± 1.9%; p = 0.033) and the contralateral leg (-1.5% ± 1.6% compared with -7.2% ± 1.4%; p = 0.014). The hamstrings also demonstrated a greater muscle-volume-sparing effect for the EAA group than for the placebo group in the involved leg (-7.4% ± 2.0% compared with -12.2% ± 1.4%; p = 0.036) and contralateral leg (-2.1% ± 1.3% compared with -7.5% ± 1.5%; p = 0.005). There were no differences between the groups in terms of functional measures or strength. Blood chemistry values varied significantly between assessments periods but did not statistically differ between groups., Conclusions: The results of the present study suggest that EAA supplementation is safe and reduces the loss of muscle volume in older adults recovering from TKA., Level of Evidence: Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Background: By the year 2030, 3.48 million older U.S. adults are projected to undergo total knee arthroplasty (TKA). Following this surgery, considerable muscle atrophy occurs, resulting in decreased strength and impaired functional mobility. Essential amino acids (EAAs) have been shown to attenuate muscle loss during periods of reduced activity and may be beneficial for TKA patients., Methods: We used a double-blind, placebo-controlled, randomized clinical trial with 28 older adults undergoing TKA. Patients were randomized to ingest either 20 g of EAAs (n = 16) or placebo (n = 12) twice daily between meals for 1 week before and 2 weeks after TKA. At baseline, 2 weeks, and 6 weeks after TKA, an MRI was performed to determine mid-thigh muscle and adipose tissue volume. Muscle strength and functional mobility were also measured at these times., Results: TKA patients receiving placebo exhibited greater quadriceps muscle atrophy, with a -14.3 ± 3.6% change from baseline to 2 weeks after surgery compared with -3.4 ± 3.1% for the EAA group (F = 5.16, P = 0.036) and a -18.4 ± 2.3% change from baseline to 6 weeks after surgery for placebo versus -6.2 ± 2.2% for the EAA group (F = 14.14, P = 0.001). EAAs also attenuated atrophy in the nonoperated quadriceps and in the hamstring and adductor muscles of both extremities. The EAA group performed better at 2 and 6 weeks after surgery on functional mobility tests (all P < 0.05). Change in quadriceps muscle atrophy was significantly associated with change in functional mobility (F = 5.78, P = 0.021)., Conclusion: EAA treatment attenuated muscle atrophy and accelerated the return of functional mobility in older adults following TKA., Trial Registration: Clinicaltrials.gov NCT00760383.

Total knee arthroplasty (TKA) is the most common and a cost-effective surgical remediation for older adults with long-standing osteoarthritis. In parallel with the expanding population of older adults, the number of TKAs performed annually is projected to be 3.48 million by 2030. During this surgery, a tourniquet is used to stop blood flow to the operative leg. However, the molecular pathways that are affected by tourniquet use during TKA continue to be elucidated. We hypothesized that components of the catabolic FoxO3a (i.e., MuRF1, MAFbx, and Bnip3) pathway, as well as the cellular stress pathways [i.e., stress-activated protein kinase (SAPK)/JNK and MAPKs], are upregulated during TKA. The purpose of this study was to measure changes in transcripts and proteins involved in muscle cell catabolic and stress-activated pathways. We obtained muscle biopsies from subjects, 70 ± 1.3 yr, during TKA, from the vastus lateralis at baseline (before tourniquet inflation), during maximal ischemia (just before tourniquet release), and during reperfusion. Total tourniquet time was 43 ± 2 min and reperfusion time was 16 ± 1. Significant increases in FoxO3a downstream targets, MAFbx and MuRF1, were present for mRNA levels during ischemia (MAFbx, P = 0.04; MuRF1, P = 0.04), and protein expression during ischemia (MAFbx, P = 0.002; MuRF1, P = 0.001) and reperfusion (MuRF1, P = 0.002). Additionally, stress-activated JNK gene expression (P = 0.01) and protein were elevated during ischemia (P = 0.001). The results of this study support our hypothesis that protein degradation pathways are stimulated during TKA. Muscle protein catabolism is likely to play a role in the rapid loss of muscle volume measured within 2 wk of this surgery.

Total knee arthroplasty (TKA) utilizes a tourniquet to reduce blood loss, maintain a clear surgical "bloodless" field, and to ensure proper bone-implant cementing. In 2007, over 600,000 TKAs were performed in the United States, and this number is projected to increase to 3.48 million procedures performed annually by 2030. The acute effects of tourniquet-induced ischemia-reperfusion (I/R) on human skeletal muscle cells are poorly understood and require critical investigation, as muscle atrophy following this surgery is rapid and represents the most significant clinical barrier to long-term normalization of physical function. To determine the acute effects of I/R on skeletal muscle cells, biopsies were obtained at baseline, maximal ischemia (prior to tourniquet release), and reperfusion (following tourniquet release). Quadriceps volume was determined before and 2 wk post-TKA by MRI. We measured a 36% decrease in phosphorylation of Akt Ser(473) during ischemia and 37% during reperfusion (P < 0.05). 4E-BP1 Thr(37/46) phosphorylation decreased 29% during ischemia and 22% during reperfusion (P < 0.05). eEF2 Thr(56) phosphorylation increased 25% during ischemia and 43% during reperfusion (P < 0.05). Quadriceps volume decreased 12% in the TKA leg (P < 0.05) and tended to decrease (6%) in the contralateral leg (P = 0.1). These data suggest cap-dependent translation initiation, and elongation may be inhibited during and after TKA surgery. We propose that cap-dependent translational events occurring during surgery may precipitate postoperative changes in muscle cells that contribute to the etiology of muscle atrophy following TKA.

Objective: Experimental evaluation of comprehensive community wide programme to prevent adolescent tobacco use., Design: Eight pairs of small Oregon communities (population 1700 to 13 500) were randomly assigned to receive a school based prevention programme or the school based programme plus a community programme. Effects were assessed through five annual surveys (time 1-5) of seventh and ninth grade (ages 12-15 years) students., Intervention: The community programme included: (a) media advocacy, (b) youth anti-tobacco activities, (c) family communications about tobacco use, and (d) reduction of youth access to tobacco., Main Outcome Measure: The prevalence of self reported smoking and smokeless tobacco use in the week before assessment., Results: The community programme had significant effects on the prevalence of weekly cigarette use at times 2 and 5 and the effect approached significance at time 4. An effect on the slope of prevalence across time points was evident only when time 2 data points were eliminated from the analysis. The intervention affected the prevalence of smokeless tobacco among grade 9 boys at time 2. There were also significant effects on the slope of alcohol use among ninth graders and the quadratic slope of marijuana for all students., Conclusion: The results suggest that comprehensive community wide interventions can improve on the preventive effect of school based tobacco prevention programmes and that effective tobacco prevention may prevent other substance use.

Sexual coercion and its relationship to high-risk sexual behavior were examined in five samples of young women. Sample 1 (N = 22) consisted of sexually active adolescents aged 15 to 19. Samples 2 (N = 206) and 3 (N = 70) were recruited from among patients at three sexually transmitted disease clinics. Sample 4 (N = 51) consisted of young homeless women living on the street in a large city. Sample 5 (N = 51) was recruited from among young women on a college campus. Across all samples, 44.4% of women indicated that they had been forced into some form of sexual activity against their will. Self-reports of sexually coercive experiences were consistently related to risky sexual behavior. It appears that many young women are coerced into engaging in high-risk sexual behavior. This implies the need for greater attention to male coercive sexual behavior and women's skills for coping with such behavior.

Longitudinal models of the development of adolescent smoking and smokeless tobacco (ST) use were tested for a sample of 643 adolescents, age 14 to 17. The sample was assessed at three time points. Smoking, smokeless tobacco, and other problem behaviors formed a single problem behavior factor. Structural equation modeling indicated that inadequate parental monitoring and association with deviant peers at Time 2 predicted tobacco use at Time 3. When parental and peer smoking at Time 2 were added to the model, each accounted for significant variance in predicting Time 3 smoking, but inadequate parental monitoring and association with deviant peers still accounted for some of the variance in Time 3 smoking. In predicting boys' smokeless tobacco use, monitoring at Time 2 predicted smokeless tobacco use, but only when parental approval of ST use was not included. Fathers approval of ST use at Time 2 predicted ST use at Time 3, while maternal disapproval predicted its use.

This study supports a model of adolescents' risky sexual behavior in which this behavior is seen as a product of the same peer and family factors which influence a wide range of problem behaviors. The Patterson et al. (1992) model of peer and parental factors associated with adolescents' sexual risk-taking behavior was tested on three independent samples of adolescents, ages 14 through 18. Adolescents whose peers were reported to engage in diverse problem behaviors were more likely to engage in risky sexual behavior. Poor parental monitoring and parent-child coercive interactions were associated having deviant peers, and poor parental monitoring also had a direct relationship to risky sexual behavior. Family involvement was associated with fewer parent-child coercive interactions. Less availability of parental figures in the family was directly associated with risky sexual behavior and was also associated with poorer parental monitoring.