Gender differences in perceived stress and coping among college students.

BACKGROUND: Many college students register each semester for courses, leading to productive careers and fulfilled lives. During this time, the students have to manage many stressors stemming from academic, personal, and, sometimes, work lives. Students, who lack appropriate stress management skills, may find it difficult to balance these responsibilities. OBJECTIVES: This study examined stress, coping mechanisms, and gender differences in undergraduate students towards the end of the semester. DESIGN AND METHOD: University students (n = 448) enrolled in three different undergraduate exercise science courses were assessed. Two instruments, the Perceived Stress Scale and Brief Cope, were administered during the twelfth week of the semester, four weeks prior to final exams. T-tests were used to detect gender differences for the stress levels and coping strategies. RESULTS: Overall, females indicated higher levels of stress than their male counterparts. Gender differences were evident in both coping dimensions and individual coping strategies used. Females were found to utilize the emotion-focused coping dimension and endorsed the use of four coping strategies more often than males. These included self-distraction, emotional support, instrumental support, and venting. CONCLUSIONS: This research adds to the existing literature by illuminating the level of perceived stress and different coping strategies used by undergraduate female and male students. In turn, students may need educational interventions to develop effective and healthy coping strategies to last a lifetime. Faculty and other university officials may want to highlight and understand these various factors to protect the students' wellbeing in their classes.

A comparison of acute changes in muscle thickness between A-mode and B-mode ultrasound.

OBJECTIVE: The purpose of this study was to compare acute changes in muscle thickness (MT) between A-mode and B-mode ultrasound before and after four sets of biceps curls. APPROACH: Participants visited the laboratory on two separate occasions. The first visit consisted of paperwork and one repetition maximum (1RM) strength assessment. During the second visit, participants performed four sets of biceps curls to volitional failure using an exercise load equal to 70% of 1RM or a time-matched non-exercise control. MT measurements were taken before and immediately after exercise. MT measures were taken using both A-mode and B-mode ultrasound. MAIN RESULTS: Results are displayed as mean (SD). A total of 49 resistance-trained men (n = 24) and women (n = 25) completed the study. There was no group (experimental versus control) by mode (A-mode versus B-mode) by time interaction (p  = 0.442). However, there was a group (experimental versus control) × time (pre versus post) interaction (p  < 0.001). Muscle thickness increased from pre (3.61 (0.86) cm) to post exercise (4.06 (0.92) cm) in the experimental group (p  < 0.001). However, there was no change from pre (3.46 (0.78) cm) to post (3.48 (0.78) cm) in the time-matched control group (p  = 0.237). There was a main effect for ultrasound mode (A-mode versus B-mode) (p  < 0.001). Muscle thickness values as measured by A-mode ultrasound were lower than those measured by B-mode ultrasound pre (A-mode = 3.43 (0.79) cm versus B-mode = 3.63 (0.84) cm) and post (A-mode = 3.67 (0.87) cm versus B-mode = 3.83 (0.91) cm) intervention. SIGNIFICANCE: MT measurements taken using A-mode ultrasound are lower than those of B-mode ultrasound. Despite this difference, it appears A-mode can detect similar acute changes in MT following resistance exercise when compared to B-mode ultrasound. These results suggest that A-mode ultrasound can serve as a useful tool when examining acute changes in MT.

Transforming the Nursing Classroom into a Clinical Setting.

Providing clinical opportunities for students to gain experience in managing cardiac dysrhythmias is a challenge for nursing faculty. High-risk experiences are often not available for all students or are too life-threatening to entrust to students. Faculty shortages and increasing enrollments add to declines in clinical opportunities. The use of human patient simulation (HPS) has added opportunities to experience high-risk, low-frequency clinical situations. HPS may be employed in the classroom setting to teach content related to dysrhythmia treatments. This innovative approach to HPS utilization engages students and helps them apply theory into clinical nursing practice.

Volume-equated high- and low-repetition daily undulating programming strategies produce similar hypertrophy and strength adaptations.

The overarching aim of this study was to compare volume-equated high-repetition daily undulating periodization (DUPHR) versus a low-repetition daily undulating periodization (DUPLR) program for muscle performance. Sixteen college-aged (23 ± 3 years) resistance-trained males were counterbalanced into 2 groups: (i) DUPHR (n = 8), with a weekly training order of 12 repetitions (Day 1), 10 repetitions (Day 2), and 8 repetitions (Day 3); and (ii) DUPLR (n = 8), with a weekly training order of 6 repetitions (Day 1), 4 repetitions (Day 2), and 2 repetitions (Day 3). Both groups trained 3 times/week for 8 weeks on nonconsecutive days, with pre- and post-training testing during weeks 1 and 8. Participants performed only squat and bench press exercises each session. Changes in one-repetition maximum (1RM) strength, muscle thickness (MT), and muscular endurance (ME) were assessed. Both groups significantly increased 1RM strength for both squat and bench press (p < 0.01), and no group differences existed (p > 0.05). Similarly, both groups experienced significant increases in chest, lateral quadriceps distal, and anterior quadriceps MT (p < 0.05), but no change was present in either group for lateral quadriceps mid MT (p < 0.05). No group differences were discovered for changes in MT (p > 0.05). ME did not significantly change in the squat or bench press for either group (p > 0.05); however, for squat ME, a moderate effect size was observed for DUPHR (0.57) versus a trivial effect size for DUPLR (0.17). Our findings suggest that in previously trained males, training volume is a significant contributor to strength and hypertrophy adaptations, which occur independently of specific repetition ranges.

Avascular necrosis in a HIV patient receiving ritonavir and inhaled fluticasone.

We report a case of severe bilateral knee avascular necrosis in a HIV-positive man receiving ritonavir and inhaled fluticasone. This case highlights the need for a thorough medication history in patients on ritonavir-based antiretroviral therapy, especially where multiple prescribers are involved in the patient's care.

International society of sports nutrition position stand: caffeine and performance.

Position Statement: The position of The Society regarding caffeine supplementation and sport performance is summarized by the following seven points: 1.) Caffeine is effective for enhancing sport performance in trained athletes when consumed in low-to-moderate dosages (~3-6 mg/kg) and overall does not result in further enhancement in performance when consumed in higher dosages (>/= 9 mg/kg). 2.) Caffeine exerts a greater ergogenic effect when consumed in an anhydrous state as compared to coffee. 3.) It has been shown that caffeine can enhance vigilance during bouts of extended exhaustive exercise, as well as periods of sustained sleep deprivation. 4.) Caffeine is ergogenic for sustained maximal endurance exercise, and has been shown to be highly effective for time-trial performance. 5.) Caffeine supplementation is beneficial for high-intensity exercise, including team sports such as soccer and rugby, both of which are categorized by intermittent activity within a period of prolonged duration. 6.) The literature is equivocal when considering the effects of caffeine supplementation on strength-power performance, and additional research in this area is warranted. 7.) The scientific literature does not support caffeine-induced diuresis during exercise, or any harmful change in fluid balance that would negatively affect performance.

The effect of beta-alanine supplementation on neuromuscular fatigue in elderly (55-92 Years): a double-blind randomized study.

BACKGROUND: Ageing is associated with a significant reduction in skeletal muscle carnosine which has been linked with a reduction in the buffering capacity of muscle and in theory, may increase the rate of fatigue during exercise. Supplementing beta-alanine has been shown to significantly increase skeletal muscle carnosine. The purpose of this study, therefore, was to examine the effects of ninety days of beta-alanine supplementation on the physical working capacity at the fatigue threshold (PWCFT) in elderly men and women. METHODS: Using a double-blind placebo controlled design, twenty-six men (n = 9) and women (n = 17) (age +/- SD = 72.8 +/- 11.1 yrs) were randomly assigned to either beta-alanine (BA: 800 mg x 3 per day; n = 12; CarnoSyntrade mark) or Placebo (PL; n = 14) group. Before (pre) and after (post) the supplementation period, participants performed a discontinuous cycle ergometry test to determine the PWCFT. RESULTS: Significant increases in PWCFT (28.6%) from pre- to post-supplementation were found for the BA treatment group (p < 0.05), but no change was observed with PL treatment. These findings suggest that ninety days of BA supplementation may increase physical working capacity by delaying the onset of neuromuscular fatigue in elderly men and women. CONCLUSION: We suggest that BA supplementation, by improving intracellular pH control, improves muscle endurance in the elderly. This, we believe, could have importance in the prevention of falls, and the maintenance of health and independent living in elderly men and women.

Effects of creatine supplementation on the onset of neuromuscular fatigue threshold and muscle strength in elderly men and women (64 - 86 years).

OBJECTIVES: This study examined the effects of 14 days of creatine supplementation on the physical working capacity at fatigue threshold (PWCFT), maximal isometric grip strength (GRIP), sit-to-stand (STS), and body weight (BW) in elderly men and women. DESIGN: Using a double blind cross-over design, fifteen men (n = 7) and women (n = 8) (age +/- SD = 74.5 +/- 6.4 yrs) were randomly assigned to either the creatine (CR) (20g.d-1 during week 1 decreasing to 10g.d-1 at week 2) or Placebo (PL) group. After a 4 to 6 week washout period, the subjects were assigned the other treatment. Before (pre) and after (post) the supplementation period, participants performed a discontinuous, cycle ergometry test to determine the PWCFT. In addition, subjects performed STS, GRIP, BW test prior to and post treatment. SETTING: Southeastern part of the United States. RESULTS: Significant increases in GRIP (6.7%) and PWCFT (15.6%) from pre- to post-supplementation were found for the CR (p < 0.05) treatment, but no change for the PL treatment was observed. However, no significant change (p superior 0.05) was noted for STS or BW for either treatment. CONCLUSION: These findings suggest that 14 days of CR supplementation may increase upper body grip strength and increase physical working capacity by delaying neuromuscular fatigue in the elderly men and women in this study. While more research is needed, CR supplementation may improve upper body grip strength and lower body muscle endurance which may be important for maintaining health and independent living in elderly men and women.

Barriers and motivations to exercise in older adults.

Although exercise is an established component in the management of many chronic diseases associated with aging, activity levels tend to progressively decline with increasing age. Given the growing proportion of older adults, these suboptimal levels of physical activity represent an increasing public health problem. The predicators of adherence elucidated in younger adults are unreliable in elderly populations. Age-specific barriers and motivators unique to this cohort are relevant and must be acknowledged. The identification of reliable predictors of exercise adherence will allow healthcare providers to effectively intervene and change patterns of physical activity in sedentary elderly. In particular, because older patients respect their physician's advice and have regular contact with their family doctor, physicians can play a key and pivotal role in the initiation and maintenance of exercise behavior among the older population.

Past and recent physical activity and bone mineral density in college-aged women.

Low bone mineral density (BMD) has been determined as an independent factor of osteoporosis. The purpose of this study was to assess physical activity's effect on BMD in college-aged women. Bone density measurements were obtained. A survey was administered to assess past and recent physical activity levels. Logistic regression revealed high school sports participation and lean tissue were significant predictors of femoral BMD, whereas present physical activity and lean tissue were significant predictors of spinal BMD. Women in the present study who did not participate in high school sports were 7 times more likely to have low BMD than were those who participated. This study revealed a protective effect of past and present physical activity on BMD in college-aged women. Children and young adults should be encouraged to participate in physical activity because it helps reduce their risk factors for osteoporosis later in life.

A "conservative" approach to iron supplementation during pregnancy.

A review of current knowledge about iron metabolism during pregnancy and the evidence from various studies on the effects of iron supplementation in pregnancy on maternal, fetal, and infant outcomes suggest that the implicit goal of current recommendations regarding iron supplementation may be to achieve the highest hemoglobin concentration possible. This goal is only weakly related to improved maternal and infant outcomes in the current pregnancy or to improved maternal iron stores long-term. Indeed, the claim that iron supplementation is universally innocuous is shown to be controversial. For women in developed countries who are generally clinically healthy and have access to adequate nutrition, the benefits of iron supplementation are unclear, and there may be risks. Thus, a better "conservative" approach may be that such women do not require routine iron supplementation during pregnancy. The midwifery philosophy of individualizing care based on a woman's history and health status is one that should be taken in approaching the issue of iron supplementation in pregnancy.

Impaired intramembranous bone formation during bone repair in the absence of tumor necrosis factor-alpha signaling.

Tumor necrosis factor-alpha (TNF-alpha) is known to mediate bone resorption; however, its role in osteogenesis has not been fully elucidated. In order to investigate the direct role of TNF-alpha signaling in the recruitment and differentiation of osteoblasts, two separate models of bone repair were used, marrow ablation and simple transverse fractures. These models were carried out in the tibiae of both wild-type and knock-out mice in which both TNF-alpha receptors (p55(-/-)/p75(-/-)) had been ablated. Marrow ablation is a unique model in which robust intramembranous bone formation is induced without an endochondral component, followed by remodeling and restoration of the original trabecular architecture of the bone marrow. In contrast, fracture repair proceeds concurrently through both endochondral and intramembranous processes of new bone tissue formation. In both models of bone repair, healing was delayed in the TNF-alpha receptor (p55(-/-)/p75(-/-)) deficient mice. In the marrow ablation model, young osteoblasts were recruited into the marrow space by day three in the wild-type mice, while the TNF-alpha (p55(-/-)/p75(-/-)) mice had only granulation tissue in the marrow cavity. Type I collagen and osteocalcin mRNA expressions were reduced approximately 30 and approximately 50%, respectively, of the control values in the TNF-alpha receptor ablated mice. In the fracture repair model there was almost a complete absence of the initial intramembranous bone formation on the periosteal surface in the TNF-alpha (p55(-/-)/p75(-/-)) mice. As healing progressed however, the callus tissues were greatly enlarged, and there was a delay in hypertrophy of the chondrocytes and the resorption of cartilage tissue. While during the initial period of fracture repair there was a marked reduction in the expression of both type I collagen and osteocalcin mRNAs in the TNF-alpha (p55(-/-)/p75(-/-)) mice, levels of these mRNAs were elevated by approximately 10-20% over the wild type at the later time points in the absence of endochondral resorption of the callus. The lack of inhibition of osteogenesis during endochondral resorption suggests that a different set of signals are involved in the recruitment of osteogenic cells during endochondral repair then during intramembranous bone formation. Co-culture of chondrocytes with a mesenchymal stem cell line was carried out to examine if chondrocytes themselves produced paracrine factors that promote osteogenic differentiation. These experiments demonstrated that chondrocytes do indeed produce factors that promoted osteogenic differentiation. In summary, the results presented here suggest that TNF-alpha plays a crucial role in promoting postnatal bone repair through the induction of osteoprogenitor cell recruitment or osteogenic cell activation in the context of intramembranous bone formation. These results further suggest that the signals that promote osteogenesis during endochondral bone formation are different from those involved in intramembranous bone formation.

Aortic valve replacement in geriatric patients: determinants of in-hospital mortality.

BACKGROUND: Aortic valve replacement is a common procedure in elderly patients. There has been a great deal of controversy about the risks associated with early mortality. Uncertainty of the risk associated with a small valve continues to remain controversial. This study was designed to identify the risk factors influencing early mortality and establish an accurate model for the prediction of in-hospital mortality. METHODS: One hundred eighty septuagenarians and octogenarians (58% women; mean age, 76 +/- 4.7 years) underwent primary isolated aortic valve replacement between 1986 and 1997. There was an overall mortality of 16.7% (n = 180). Patients with a body surface area less than 1.8 m2 had an in-hospital mortality of 23.2% (n = 95) compared with 8.1% (n = 74; p = 0.009) for patients with a body surface area of 1.8 m2 or more. Patients with a cardiopulmonary bypass time of less than 100 minutes experienced an early mortality of 8.9% (n = 56) compared with a 10.2% (n = 59) early mortality for patients on bypass time between 100 and 124 minutes and a 29.6% (n = 64) early mortality in patients with a pump time longer than 124 minutes (p = 0.040). RESULTS: Multivariate logistic regression analysis identified small body surface area and long cardiopulmonary bypass time as independent risk factors. A higher mortality was seen in female patients and patients receiving smaller valves. However, there was a strong correlation between small body surface area, small valve size, and female gender. CONCLUSIONS: Small body surface area and long cardiopulmonary bypass time are two independent risk factors in early mortality for elderly patients undergoing primary isolated aortic valve replacement. The use of small valves does not influence early mortality.

The safety and efficacy of GM-CSF as an adjuvant in hepatitis B vaccination of chronic hemodialysis patients who have failed primary vaccination.

BACKGROUND: End-stage renal disease and the need for chronic hemodialysis is an indication for hepatitis B vaccination, but up to half of dialysis patients fail to respond to a 40 microg/dose i.m. three-dose primary series of recombinant hepatitis B vaccine. Only another 10-20% respond to additional boosting doses of vaccine. PATIENTS AND METHODS: Since GM-CSF has been shown to be an effective adjuvant for hepatitis B vaccine in healthy subjects and multiple animal vaccine models, we conducted a randomized, double-blind trial of GM-CSF with recombinant hepatitis B vaccine in chronic hemodialysis patients. Patients with negative hepatitis B surface antibody and antigen who had received at least three doses of recombinant hepatitis B vaccine without response (antibody titre < 10 mIU/ml) were randomized to placebo, 40 microg, or 80 microg of GM-CSF given with 40 microg recombinant hepatitis B vaccine i.m. at the same site. Clinical and laboratory studies for safety assessment were done on days 1 and 3, and hepatitis B surface antibody titres were measured at baseline and days 21 and 180 after the study injections. RESULTS: No significant local or systemic toxicity was noted from the co-injections. The rates of response and geometric mean titre (GMT) were equivalent among all three study groups: placebo 6/10 developed antibodies, GMT 22.1 mIU/ml; 40 microg GM-CSF 3/10 developed antibodies, GMT 5.4 mIU; and 80 microg GM-CSF 3/8 developed antibodies, GMT 9.7 mIU/ml. Six months after vaccination, antibody titres were available for 11 of the 12 day 21 positive responders; only 4 of these 11 patients remained antibody positive at 6 months. CONCLUSION: GM-CSF given in a single 40 microg and 80 microg i.m. dose was not an effective adjuvant with hepatitis B vaccine in chronic hemodialysis patients who had previously failed to respond to hepatitis B immunization.

Carbocyclic influenza neuraminidase inhibitors possessing a C3-cyclic amine side chain: synthesis and inhibitory activity.

As part of our continuing work in the area of influenza neuraminidase inhibitors, a series of C3-aza inhibitors possessing a cyclic amine side chain was synthesized and evaluated for influenza neuraminidase inhibitory activity. Analogues possessing a six-, seven- and eight-membered ring, 4c-e, respectively, at the C3 position exhibited excellent influenza B neuraminidase inhibition.

Phosphorylation represses Ets-1 DNA binding by reinforcing autoinhibition.

Phosphorylation of transcription factors is a key link between cell signaling and the control of gene expression. Here we report that phosphorylation regulates DNA binding of the Ets-1 transcription factor by reinforcing an autoinhibitory mechanism. Quantitative DNA-binding assays show that calcium-dependent phosphorylation inhibits Ets-1 DNA binding 50-fold. The four serines that mediate this inhibitory effect are distant from the DNA-binding domain but near structural elements required for autoinhibition. Mutational analyses demonstrate that an intact inhibitory module is required for phosphorylation-dependent regulation. Partial proteolysis studies indicate that phosphorylation stabilizes an inhibitory conformation. These findings provide a structural mechanism for phosphorylation-dependent inhibition of Ets-1 DNA binding and demonstrate a new function for inhibitory modules as structural mediators of negative signaling events.

Auto-inhibition and partner proteins, core-binding factor beta (CBFbeta) and Ets-1, modulate DNA binding by CBFalpha2 (AML1).

Core-binding factor alpha2 (CBFalpha2; otherwise known as AML1 or PEBP2alphaB) is a DNA-binding subunit in the family of core-binding factors (CBFs), heterodimeric transcription factors that play pivotal roles in multiple developmental processes in mammals, including hematopoiesis and bone development. The Runt domain in CBFalpha2 (amino acids 51 to 178) mediates DNA binding and heterodimerization with the non-DNA-binding CBFbeta subunit. Both the CBFbeta subunit and the DNA-binding protein Ets-1 stimulate DNA binding by the CBFalpha2 protein. Here we quantify and compare the extent of cooperativity between CBFalpha2, CBFbeta, and Ets-1. We also identify auto-inhibitory sequences within CBFalpha2 and sequences that modulate its interactions with CBFbeta and Ets-1. We show that sequences in the CBFalpha2 Runt domain and sequences C terminal to amino acid 214 inhibit DNA binding. Sequences C terminal to amino acid 214 also inhibit heterodimerization with the non-DNA-binding CBFbeta subunit, particularly heterodimerization off DNA. CBFbeta rescinds the intramolecular inhibition of CBFalpha2, stimulating DNA binding approximately 40-fold. In comparison, Ets-1 stimulates CBFalpha2 DNA binding 7- to 10-fold. Although the Runt domain alone is sufficient for heterodimerization with CBFbeta, sequences N terminal to amino acid 41 and between amino acids 190 and 214 are required for cooperative DNA binding with Ets-1. Cooperative DNA binding with Ets-1 is less pronounced with the CBFalpha2-CBFbeta heterodimer than with CBFalpha2 alone. These analyses demonstrate that CBFalpha2 is subject to both negative regulation by intramolecular interactions, and positive regulation by two alternative partnerships.

Auto-inhibition of Ets-1 is counteracted by DNA binding cooperativity with core-binding factor alpha2.

Auto-inhibition is a common transcriptional control mechanism that is well characterized in the regulatory transcription factor Ets-1. Autoinhibition of Ets-1 DNA binding works through an inhibitory module that exists in two conformations. DNA binding requires a change in the inhibitory module from the packed to disrupted conformation. This structural switch provides a mechanism to tightly regulate Ets-1 DNA binding. We report that the Ets-1 partner protein core-binding factor alpha2 (CBFalpha2; also known as AML1 or PEBP2) stimulates Ets-1 DNA binding and counteracts auto-inhibition. Support for this conclusion came from three observations. First, the level of cooperative DNA binding (10-fold) was similar to the level of repression by auto-inhibition (10- to 20-fold). Next, a region necessary for cooperative DNA binding mapped to the inhibitory module. Third, an Ets-1 mutant with a constitutively disrupted inhibitory module did not bind DNA cooperatively with CBFalpha2. Furthermore, two additional lines of evidence indicated that CBFalpha2 affects the structural switch by direct interactions with Ets-1. First, the retention of cooperative DNA binding on nicked duplexes eliminated a potential role of through-DNA effects. Second, cooperative DNA binding was observed on composite sites with altered spacing or reversed orientation. We suggest that only protein interactions can accommodate this observed flexibility. These findings provide a mechanism by which CBF relieves the auto-inhibition of Ets-1 and illustrates one strategy for the synergistic activity of regulatory transcription factors.

Synthesis and evaluation of 1,4,5,6-tetrahydropyridazine derivatives as influenza neuraminidase inhibitors.

1,4,5,6-Tetrahydropyridazine derivative 15 and its C-5 epimer 19, which possessed side chains similar to GS4071, were synthesized via a hetero Diels-Alder reaction, and evaluated as influenza neuraminidase inhibitors. Compounds 15 and 19 exhibited a microM range of influenza neuraminidase inhibitory activity.

Inhibition of Ets-1 DNA binding and ternary complex formation between Ets-1, NF-kappaB, and DNA by a designed DNA-binding ligand.

Sequence-specific pyrrole-imidazole polyamides can be designed to interfere with transcription factor binding and to regulate gene expression, both in vitro and in living cells. Polyamides bound adjacent to the recognition sites for TBP, Ets-1, and LEF-1 in the human immunodeficiency virus, type 1 (HIV-1), long terminal repeat inhibited transcription in cell-free assays and viral replication in human peripheral blood lymphocytes. The DNA binding activity of the transcription factor Ets-1 is specifically inhibited by a polyamide bound in the minor groove. Ets-1 is a member of the winged-helix-turn-helix family of transcription factors and binds DNA through a recognition helix bound in the major groove with additional phosphate contacts on either side of this major groove interaction. The inhibitory polyamide possibly interferes with phosphate contacts made by Ets-1, by occupying the adjacent minor groove. Full-length Ets-1 binds the HIV-1 enhancer through cooperative interactions with the p50 subunit of NF-kappaB, and the Ets-inhibitory polyamide also blocks formation of ternary Ets-1. NF-kappaB.DNA complexes on the HIV-1 enhancer. A polyamide bound adjacent to the recognition site for NF-kappaB also inhibits NF-kappaB binding and ternary complex formation. These results broaden the application range of minor groove-binding polyamides and demonstrate that these DNA ligands are powerful inhibitors of DNA-binding proteins that predominantly use major groove contacts and of cooperative protein-DNA ternary complexes.