Unconventional medicine in the United States. Prevalence, costs, and patterns of use

BACKGROUND

Many people use unconventional therapies for health problems, but the extent of this use and the costs are not known. We conducted a national survey to determine the prevalence, costs, and patterns of use of unconventional therapies, such as acupuncture and chiropractic.

METHODS

We limited the therapies studied to 16 commonly used interventions neither taught widely in U.S. medical schools nor generally available in U.S. hospitals. We completed telephone interviews with 1539 adults (response rate, 67 percent) in a national sample of adults 18 years of age or older in 1990. We asked respondents to report any serious or bothersome medical conditions and details of their use of conventional medical services; we then inquired about their use of unconventional therapy.

RESULTS

One in three respondents (34 percent) reported using at least one unconventional therapy in the past year, and a third of these saw providers for unconventional therapy. The latter group had made an average of 19 visits to such providers during the preceding year, with an average charge per visit of $27.60. The frequency of use of unconventional therapy varied somewhat among socio-demographic groups, with the highest use reported by nonblack persons from 25 to 49 years of age who had relatively more education and higher incomes. The majority used unconventional therapy for chronic, as opposed to life-threatening, medical conditions. Among those who used unconventional therapy for serious medical conditions, the vast majority (83 percent) also sought treatment for the same condition from a medical doctor; however, 72 percent of the respondents who used unconventional therapy did not inform their medical doctor that they had done so. Extrapolation to the U.S. population suggests that in 1990 Americans made an estimated 425 million visits to providers of unconventional therapy. This number exceeds the number of visits to all U.S. primary care physicians (388 million). Expenditures associated with use of unconventional therapy in 1990 amounted to approximately $13.7 billion, three quarters of which ($10.3 billion) was paid out of pocket. This figure is comparable to the $12.8 billion spent out of pocket annually for all hospitalizations in the United States.

CONCLUSIONS

The frequency of use of unconventional therapy in the United States is far higher than previously reported. Medical doctors should ask about their patients' use of unconventional therapy whenever they obtain a medical history.

Monitoring training in athletes with reference to overtraining syndrome

PURPOSE

Overtraining is primarily related to sustained high load training, often coupled with other stressors. Studies in animal models have suggested that unremittingly heavy training (monotonous training) may increase the likelihood of developing overtraining syndrome. The purpose of this study was to extend our preliminary observations by relating the incidence of illnesses and minor injuries to various indices of training.

METHODS

We report observations of the relationship of banal illnesses (a frequently cited marker of overtraining syndrome) to training load and training monotony in experienced athletes (N = 25). Athletes recorded their training using a method that integrates the exercise session RPE and the duration of the training session. Illnesses were noted and correlated with indices of training load (rolling 6 wk average), monotony (daily mean/standard deviation), and strain (load x monotony).

RESULTS

It was observed that a high percentage of illnesses could be accounted for when individual athletes exceeded individually identifiable training thresholds, mostly related to the strain of training.

CONCLUSIONS

These suggest that simple methods of monitoring the characteristics of training may allow the athlete to achieve the goals of training while minimizing undesired training outcomes.

Interventions for promoting physical activity

BACKGROUND

Little is known about the effectiveness of strategies to enable people to achieve an increase in their physical activity.

OBJECTIVES

To assess the effects of interventions for promoting physical activity in adults aged 16 years and older, not living in an institution.

SEARCH STRATEGY

We searched CENTRAL (Issue 4, 2001), MEDLINE, EMBASE, CINAHL, PsychLIT, BIDS ISI, SPORTDISCUS, SIGLE, SCISEARCH (from earliest date available to December 2001) and reference lists of articles.

SELECTION CRITERIA

Randomised, controlled, trials comparing different interventions to encourage sedentary adults not living in an institution to become physically active. Studies required a minimum of six months follow up from the start of the intervention to the collection of final data and either used an intention to treat analysis or, failing that, had no more than 20% loss to follow up.

DATA COLLECTION AND ANALYSIS

At least two reviewers independently assessed each study quality and extracted data. Study authors were contacted for additional information where necessary. Standardised mean differences and 95% confidence intervals were calculated for continuous measures of self reported physical activity and cardio-respiratory fitness. For studies with dichotomous outcomes, odds ratios and 95% confidence intervals were calculated.

MAIN RESULTS

The effect of interventions on self reported physical activity (11 studies; 3940 participants) was positive and moderate, with a pooled standardised mean difference of 0.31 (95% CI 0.12 to 0.50), as was the effect on cardio-respiratory fitness (7 studies; 1406 participants) pooled SMD 0.4 (95% CI 0.09 to 0.70). The effect of interventions in achieving a predetermined threshold of physical activity (6 studies; 2313 participants) was not significant with an odds ratio of 1.30 (95% CI 0.87 to 1.95). There was significant heterogeneity in the reported effects as well as heterogeneity in characteristics of the interventions. The heterogeneity in reported effects was reduced in higher quality studies, when physical activity was self-directed with some professional guidance and when there was on-going professional support.

AUTHORS' CONCLUSIONS

Our review suggests that physical activity interventions have a moderate effect on self reported physical activity and cardio-respiratory fitness, but not on achieving a predetermined level of physical activity. Due to the clinical and statistical heterogeneity of the studies, only limited conclusions can be drawn about the effectiveness of individual components of the interventions. Future studies should provide greater detail of the components of interventions.

Comparative analysis of physiologic responses to three different maximal graded exercise test protocols in healthy women

The purpose of this study was to compare the three most commonly used maximal graded exercise test (GXT) protocols in healthy women. Submaximal and maximal metabolic and hemodynamic responses were determined from two treadmill protocols, Bruce and Balke, and a bicycle protocol, in 49 women. Maximum oxygen uptake (VO2 max) was significantly different among protocols (Bruce=40.3, Balke=38.4, and Bike=36.6 ml/kg . min -1). Maximum heart rate (HR max) was significantly lower during Bike (178 beats/min) than during Bruce (182) and Balke (183) protocols. No differences in rate of increase in HR or systolic blood pressure (BP) per increase in multiples of the rest metabolic (METs) were found between Bruce and Balke protocols. The rate of recovery of HR and systolic BP was not different among tests. Comparisons of active and sedentary groups showed differences in VO2 max and submaximal HR and recovery HR at common minutes; however, the rate of increase in HR and systolic BP during exercise and the rate of decrease during recovery were not significantly different. Prediction of VO2 max with Bruce and Balke protocols from treadmill time was r=0.91 (SEE +/- 2.7 ml/kg . min -1) and r=0.94 (SEE 2.2 ml/kg . min -1), respectively. These data suggest a difference between men and women in increased HR and systolic BP per METs increase in exertion.

Effects of specific versus cross-training on running performance

The cross-training (XT) hypothesis suggests that despite the principle of specificity of training, athletes may improve performance in one mode of exercise by training using another mode. To test this hypothesis we studied 30 well-trained individuals (10 men, 20 women) in a randomized longitudinal trail. Subjects were evaluated before and after 8 weeks of enhanced training (+10%/week), accomplished by adding either running (R) or swimming (XT) to baseline running, versus continued baseline running (C). Both R (-26.4s) and XT (-13.2s) improved time trial (3.2 km) performance, whereas C did not (-5.4s). There were no significant changes during treadmill running in maximum oxygen uptake (VO2peak; -0.2, -6.0, and +2.7%), steady state submaximal VO2 at 2.68 m.s-1 (-1.2, -3.3 and +0.2 ml.kg-1.min-1), velocity at VO2peak (+0.05, +0.25 and +0.09 m.s-1) or accumulated O2 deficit (+11.2, -6.1 and +9.4%) in the R, XT or C groups, respectively. There was a significant increase in velocity associated with a blood lactate concentration of 4 mmol.l-1 in R but not in XT or C (+0.32, +0.07 and +0.08 m.s-1). There were significant changes in arm crank VO2peak (+5%) and arm crank VO2 at 4 mmol.l-1 (+6.4%) in XT. There was no significant changes in arm crank VO2peak (+1.3 and -7.7%) or arm crank VO2 at 4 mmol.l-1 (+0.8 and +0.4%) in R or C, respectively. The data suggest that muscularly non-similar XT may contribute to improved running performance but not to the same degree as increased specific training.

Effect of exercise referral schemes in primary care on physical activity and improving health outcomes: systematic review and meta-analysis

OBJECTIVE

To assess the impact of exercise referral schemes on physical activity and health outcomes. Design Systematic review and meta-analysis.

DATA SOURCES

Medline, Embase, PsycINFO, Cochrane Library, ISI Web of Science, SPORTDiscus, and ongoing trial registries up to October 2009. We also checked study references. Study selection Design: randomised controlled trials or non-randomised controlled (cluster or individual) studies published in peer review journals.

POPULATION

sedentary individuals with or without medical diagnosis. Exercise referral schemes defined as: clear referrals by primary care professionals to third party service providers to increase physical activity or exercise, physical activity or exercise programmes tailored to individuals, and initial assessment and monitoring throughout programmes. Comparators: usual care, no intervention, or alternative exercise referral schemes.

RESULTS

Eight randomised controlled trials met the inclusion criteria, comparing exercise referral schemes with usual care (six trials), alternative physical activity intervention (two), and an exercise referral scheme plus a self determination theory intervention (one). Compared with usual care, follow-up data for exercise referral schemes showed an increased number of participants who achieved 90-150 minutes of physical activity of at least moderate intensity per week (pooled relative risk 1.16, 95% confidence intervals 1.03 to 1.30) and a reduced level of depression (pooled standardised mean difference -0.82, -1.28 to -0.35). Evidence of a between group difference in physical activity of moderate or vigorous intensity or in other health outcomes was inconsistent at follow-up. We did not find any difference in outcomes between exercise referral schemes and the other two comparator groups. None of the included trials separately reported outcomes in individuals with specific medical diagnoses. Substantial heterogeneity in the quality and nature of the exercise referral schemes across studies might have contributed to the inconsistency in outcome findings. Conclusions Considerable uncertainty remains as to the effectiveness of exercise referral schemes for increasing physical activity, fitness, or health indicators, or whether they are an efficient use of resources for sedentary people with or without a medical diagnosis.

Recovery and self-management support following primary cancer treatment

BACKGROUND

Around 2 million people are living with or beyond cancer in the UK. However, experiences and needs following primary treatment are relatively neglected. Following treatment, survivors may feel particularly vulnerable and face threats to their identity. We present a conceptual framework to inform areas of self-management support to facilitate recovery of health and well-being following primary cancer treatment.

METHODS

To explain the framework, we draw on data from two studies: UK-wide consultation about cancer patients' research priorities and survivors' self-management in the year following primary cancer treatment.

RESULTS

Self-confidence may be low following treatment. Recovery includes rebuilding lost confidence. Support to manage the impact of cancer on everyday life was a priority. Self-management support included health professionals, peers, employers, family, friends and online resources. However, support was not always available and confidence to access support could be low.

CONCLUSION

Cancer survivors may struggle to self-manage following primary treatment where confidence is low or support is lacking. Low confidence may be a significant barrier to accessing support. Supporting recovery of self-confidence is an important aspect of recovery alongside physical and psychosocial problems in the context of changing health care and cancer follow-up.

Psychosocial implications of living 5 years or more following a cancer diagnosis: a systematic review of the research evidence

Mortality associated with cancer remains high, but more people are surviving cancer. Some people experience long-term problems associated with cancer and its treatment, and there is a need to know how to support them. This systematic literature review explores primary research for psychosocial implications of long-term survival (>or=5 years) following a cancer diagnosis and interventions designed to address psychosocial problems in the long term. A systematic search of BIDS, BNI, Cancer.gov, CINAHL, Medline, PsychINFO and Web of Science was conducted to identify research publications from 1960 to 2006. Papers were selected on the basis of pre-defined criteria and rated by three independent coders. Forty-three studies met the eligibility criteria. These indicated that most people experience few problems five or more years after their diagnosis of cancer. However, 20-30% of survivors consistently reported problems associated with cancer and its treatment including physical problems, poorer quality of life, psychological distress, sexual problems, problems with social relationships and financial concerns. Not all cancer types are represented in this review. Only two intervention studies met the eligibility criteria. Research is needed to establish appropriate interventions to support those experiencing problems in the long term to enhance well-being.

Twenty-year follow-up of aerobic power and body composition of older track athletes

The purpose was to determine the aerobic power (maximal oxygen uptake) and body composition of older track athletes after a 20-yr follow-up (T3). At 20 yr, 21 subjects [mean ages: 50.5 +/- 8.5 yr at initial evaluation (T1), 60.2 +/- 8.8 yr at 10-yr follow-up (T2), and 70.4 +/- 8.8 yr at 20-yr follow-up (T3)] were divided into three intensity groups: high (H; remained elite; n = 9); moderate (M; continued frequent moderate-to-rigorous endurance training; n = 10); and low (L; greatly reduced training; n = 2). All groups decreased in maximal oxygen uptake at each testing point (H, 8 and 15%; M, 13 and 14%; and L, 18 and 34% from T1 to T2 and T2 to T3, respectively). Maximal heart rate showed a linear decrease of approximately 5-7 beats.min-1.decade-1 and was independent of training status. Body weight remained stable for the H and M groups and percent fat increased approximately 2-2.5%/decade. Although fat-free weight decreased at each testing point, there was a trend for those who began weight-training exercise to better maintain it. Cross-sectional analysis at T3 showed that leg strength and bone mineral density were generally maintained from age 60 to 89 yr. Those who performed weight training had a greater arm region bone mineral density than those who did not. These longitudinal data show that the physiological capacities of older athletes are reduced despite continued vigorous endurance exercise over a 20-yr period (approximately 8-15%/decade). Changes in body composition appeared to be less than those shown for the healthy sedentary population and were related to changes in training habits.

The relationship between age and depressive symptoms in two national surveys

There is inconsistency in the literature on the relationship between age and depressive symptoms. Although a careful review shows that some of this inconsistency can be reconciled by recognizing the nonlinear relationship (Newmann, 1989), 2 additional issues remain unclear. One is that most previous studies used depression screening scales that contain somatic items that could introduce an age bias. The other is that most previous studies combined samples of men and women even though there is evidence that the sex difference in depressive symptoms varies with age. These 2 issues are addressed in this article, using analyzed data from 2 large national surveys. There is a consistent, but quite modest, nonlinear association between age, somatic, and nonsomatic depressive symptoms in both surveys. There is no significant sex difference in the age curves.

Effect of age and training on aerobic capacity and body composition of master athletes

Maximum oxygen uptake (VO2max) and body composition have been shown to deteriorate with age. How much of the decline is attributable to aging and how much is affected by reduced physical activity is not known. The purpose of this investigation was to determine the aerobic capacity and body composition of 24 master track athletes and to evaluate the relationship to age and maintenance of training over a 10-yr period. The subjects (50-82 yr of age) were retested after a 10.1-yr follow-up (T2). All continued their aerobic training, but only 11 were still highly competitive (COMP) and continued to train at the same intensity. The other 13 athletes studied became noncompetitive (post-COMP) and reduced their training intensity. The results showed the COMP group to maintain its VO2max and maximum O2 pulse while the post-COMP group showed a significant decline (54.2-53.3 vs. 52.5-45.9 ml X kg-1 X min-1; 20.7-20.8 vs. 22.4-20.0 ml/beat from test one (T1) to T2 for the COMP vs. post-COMP groups, respectively). Maximum heart rate declined 7 beats/min for both groups. Body composition showed no difference between groups from T1 to T2. For both groups body weight declined slightly (70.0-68.9 kg), percent fat increased significantly (13.1-15.1%), and fat-free weight decreased significantly (61.0-59.0 kg). Thus, when training was maintained, aerobic capacity remained unchanged over the follow-up period. Body composition changed for both groups and may have been related to aging and/or the type of training performed.

Overtraining in endurance athletes: a brief review

Overtraining is an imbalance between training and recovery, exercise and exercise capacity, stress and stress tolerance. Stress is the sum of training and nontraining stress factors. Peripheral (short-term overtraining, STO) or peripheral and central fatigue may result (long-term overtraining, LTO). STO lasting a few days up to 2 wk is termed overreaching. STO is associated with fatigue, reduction, or stagnation of the 4 LT performance capacity (performance at 4 mmol lactate or comparable criterion), reduction of maximum performance capacity, and brief competitive incompetence. Recovery is achieved within days, so the prognosis is favorable. LTO lasting weeks or months causes overtraining syndrome or staleness. The symptomatology associated with overtraining syndrome has changed over the last 50 yr from excitation and restlessness (so-called sympathetic form) to phlegmatic behavior and inhibition (so-called parasympathetic form). Increased volume of training at a high-intensity level is likely the culprit. The parasympathetic form of overtraining syndrome dominates in endurance sports. Accumulation of exercise and nonexercise fatigue, stagnation, or reduction of the 4 LT performance capacity, reduction in maximum performance capacity, mood state disturbances, muscle soreness/stiffness, and long-term competitive incompetence can be expected. Complete recovery requires weeks and months, so the prognosis is unfavorable. Other optional or further confirmation requiring findings include changes in blood chemistry variables, hormone levels, and nocturnal urinary catecholamine excretion. Based on the findings reported, recommendations for training monitoring can be made, but their relevance in the practice must still be clarified.

Determination of optimal pacing strategy in track cycling with an energy flow model

The purpose of this study was to investigate the effect of pacing strategies on performance times in the 1000 m time trial event and the 4000 m pursuit event in track cycling. For this purpose, we simulated these events with a model based on the flow of energy in cycling. Different strategies in distributing the available anaerobic energy were evaluated and we compared model predictions of split times and final times with values achieved by cyclists during championships. The best result at the 1000 m time trial was obtained when the cyclist had the highest anaerobic peak power output and used an 'all-out' strategy. The fastest time on the 4000 m pursuit was achieved with an 'all-out' start at a high level of initial power output, followed by a constant anaerobic power output after 12 seconds, resulting in an evenly paced race. The results show that even small variations in pacing strategy may have substantial effects on performance. There seems to be an opportunity to gain a competitive advantage when individual athletes experiment with small variations in pacing strategy to find the precise individual strategy that works best under specific conditions.

The relationship between access and quality of urban green space with population physical activity

OBJECTIVES

This study examined the association between access to quality urban green space and levels of physical activity.

STUDY DESIGN

A cross-sectional examination of the relationship between access to quality urban green space and level of recreational physical activity in 4950 middle-aged (40-70 years) respondents from the European Prospective Investigation into Cancer and Nutrition (EPIC), who resided in Norwich, UK.

METHODS

Using geographic information systems (GIS), three measures of access to open green space were calculated based on distance only, distance and size of green space and distance, size and quality of green space. Multiple regression models were used to determine the relationship between the three indicators of access to open green space and level of recreational physical activity.

RESULTS

There was no evidence of clear relationships between recreational activity and access to green spaces. Non-significant associations were apparent for all variables, and there was no evidence of a clear trend in regression coefficients across quartiles of access for either the distance, size adjusted, and quality and size-adjusted models. Furthermore, the neighbourhood measures of access to green spaces showed non-significant associations with recreational physical activity.

CONCLUSIONS

Access to urban green spaces does not appear to be associated with population levels of recreational physical activity in our sample of middle-aged adults.

Cancer survivors' self-efficacy to self-manage in the year following primary treatment

PURPOSE

Cancer survivors are increasingly expected to manage the consequences of cancer and its treatment for themselves. There is evidence that self-efficacy is important for successful self-management and that this can be enhanced with support. The purpose of this study was to assess self-efficacy to manage problems in the year following primary treatment.

METHODS

This cross-sectional online survey included cancer survivors who had completed their treatment within the past 12 months. Self-efficacy was assessed and variables expected to be associated with self-efficacy were measured using validated scales including quality of life, well-being, illness perceptions, depression and social support.

RESULTS

One hundred eighty-two respondents (mean age 50; 81% female) completed the survey. They had been treated for a range of cancers; most commonly breast (45%). Self-efficacy scores varied between individuals and according to the illness-related task to be managed. Respondents were least confident in managing fatigue and most confident in accessing information about their cancer. Individuals most likely to report low self-efficacy were women, those experiencing higher levels of pain and/or depression, lower well-being scores, lower socio-economic status, low levels of social support, or a more negative perception of cancer.

CONCLUSIONS

Self-efficacy to self-manage problems faced as a consequence of cancer and its treatment can vary widely in the year following treatment. Fatigue may be particularly difficult to manage.

IMPLICATIONS FOR CANCER SURVIVORS

Variations in self-efficacy highlight the importance of assessing specific problems faced and people's confidence to manage them in order to tailor appropriate self-management support.

Potential for strength and endurance training to amplify endurance performance

The impact of adding heavy-resistance training to increase leg-muscle strength was studied in eight cycling- and running-trained subjects who were already at a steady-state level of performance. Strength training was performed 3 days/wk for 10 wk, whereas endurance training remained constant during this phase. After 10 wk, leg strength was increased by an average of 30%, but thigh girth and biopsied vastus lateralis muscle fiber areas (fast and slow twitch) and citrate synthase activities were unchanged. Maximal O2 uptake (VO2max) was also unchanged by heavy-resistance training during cycling (55 ml.kg-1.min-1) and treadmill running (60 ml.kg-1.min-1); however, short-term endurance (4-8 min) was increased by 11 and 13% (P less than 0.05) during cycling and running, respectively. Long-term cycling to exhaustion at 80% VO2max increased from 71 to 85 min (P less than 0.05) after the addition of strength training, whereas long-term running (10 km times) results were inconclusive. These data do not demonstrate any negative performance effects of adding heavy-resistance training to ongoing endurance-training regimens. They indicate that certain types of endurance performance, particularly those requiring fast-twitch fiber recruitment, can be improved by strength-training supplementation.

Psychosocial impact of breast/ovarian (BRCA1/2) cancer-predictive genetic testing in a UK multi-centre clinical cohort

This multi-centre UK study assesses the impact of predictive testing for breast and ovarian cancer predisposition genes (BRCA1/2) in the clinical context. In the year following predictive testing, 261 adults (59 male) from nine UK genetics centres participated; 91 gene mutation carriers and 170 noncarriers. Self-report questionnaires were completed at baseline (pre-genetic testing) and 1, 4 and 12 months following the genetic test result. Men were assessed for general mental health (by general health questionnaire (GHQ)) and women for general mental health, cancer-related worry, intrusive and avoidant thoughts, perception of risk and risk management behaviour. Main comparisons were between female carriers and noncarriers on all measures and men and women for general mental health. Female noncarriers benefited psychologically, with significant reductions in cancer-related worry following testing (P<0.001). However, younger female carriers (<50 years) showed a rise in cancer-related worry 1 month post-testing (P<0.05). This returned to pre-testing baseline levels 12 months later, but worry remained significantly higher than noncarriers throughout (P<0.01). There were no significant differences in GHQ scores between males and females (both carriers and noncarriers) at any time point. Female carriers engaged in significantly more risk management strategies than noncarriers in the year following testing (e.g. mammograms; 92% carriers vs 30% noncarriers). In the 12 months post-testing, 28% carriers had bilateral risk-reducing mastectomy and 31% oophorectomy. Oophorectomy was confined to older (mean 41 yrs) women who already had children. However, worry about cancer was not assuaged by surgery following genetic testing, and this requires further investigation. In all, 20% of female carriers reported insurance problems. The data show persistent worry in younger female gene carriers and confirm changes in risk management consistent with carrier status. Men were not adversely affected by genetic testing in terms of their general mental health.

A systematic review of the influence of the retail food environment around schools on obesity-related outcomes

The high prevalence of childhood obesity has led to questions about the influence of 'obesogenic' environments on children's health. Public health interventions targeting the retail food environment around schools have been proposed, but it is unclear if they are evidence based. This systematic review investigates associations between food outlets near schools and children's food purchases, consumption and body weight. We conducted a keyword search in 10 databases. Inclusion criteria required papers to be peer reviewed, to measure retailing around schools and to measure obesity-related outcomes among schoolchildren. Thirty papers were included. This review found very little evidence for an effect of the retail food environment surrounding schools on food purchases and consumption, but some evidence of an effect on body weight. Given the general lack of evidence for association with the mediating variables of food purchases and consumption, and the observational nature of the included studies, it is possible that the effect on body weight is a result of residual confounding. Most of the included studies did not consider individual children's journeys through the food environment, suggesting that predominant exposure measures may not account for what individual children actually experience. These findings suggest that future interventions targeting the food environment around schools need careful evaluation.

Unique pathway of thrombin-induced platelet aggregation mediated by glycoprotein Ib

Thrombin plays a central role in normal and abnormal hemostatic processes. It is assumed that alpha-thrombin activates platelets by hydrolyzing the protease-activated receptor (PAR)-1, thereby exposing a new N-terminal sequence, a tethered ligand, which initiates a cascade of molecular reactions leading to thrombus formation. This process involves cross-linking of adjacent platelets mediated by the interaction of activated glycoprotein (GP) IIb/IIIa with distinct amino acid sequences, LGGAKQAGDV and/or RGD, at each end of dimeric fibrinogen molecules. We demonstrate here the existence of a second alpha-thrombin-induced platelet-activating pathway, dependent on GP Ib, which does not require hydrolysis of a substrate receptor, utilizes polymerizing fibrin instead of fibrinogen, and can be inhibited by the Fab fragment of the monoclonal antibody LJIb-10 bound to the GP Ib thrombin-binding site or by the cobra venom metalloproteinase, mocarhagin, that hydrolyzes the extracellular portion of GP Ib. This alternative alpha-thrombin pathway is observed when PAR-1 or GP IIb/IIIa is inhibited. The recognition sites involved in the cross-linking of polymerizing fibrin and surface integrins via the GP Ib pathway are different from those associated with fibrinogen. This pathway is insensitive to RGDS and anti-GP IIb/IIIa antibodies but reactive with a mutant fibrinogen, gamma407, with a deletion of the gamma-chain sequence, AGDV. The reaction is not due to simple trapping of platelets by the fibrin clot, since ligand binding, signal transduction, and second messenger formation are required. The GP Ib pathway is accompanied by mobilization of internal calcium and the platelet release reaction. This latter aspect is not observed with ristocetin-induced GP Ib-von Willebrand factor agglutination nor with GP Ib-von Willebrand factor-polymerizing fibrin trapping of platelets. Human platelets also respond to gamma-thrombin, an autoproteolytic product of alpha-thrombin, through PAR-4. Co-activation of the GP Ib, PAR-1, and PAR-4 pathways elicit synergistic responses. The presence of the GP Ib pathway may explain why anti-alpha-thrombin/anti-platelet regimens fail to completely abrogate thrombosis/restenosis in the cardiac patient.

Combined aerobic and resistance training in breast cancer survivors: A randomized, controlled pilot trial

The purpose of this pilot study was to examine the effects of a combined cardiorespiratory and resistance exercise training program of short duration on the cardiorespiratory fitness, strength endurance, task specific functional muscle capacity, body composition and quality of life (QOL) in women breast cancer survivors. Sixteen subjects were randomly assigned to either a training (n = 8; age: 50 +/- 5 yrs) or control non-exercising group (n = 8; age: 51 +/- 10 yrs). The training group followed an 8-week exercise program consisting of 3 weekly sessions of 90-min duration, supervised by an experienced investigator and divided into resistance exercises and aerobic training. Before and after the intervention period, all of the subjects performed a cardiorespiratory test to measure peak oxygen uptake (VO2peak), a dynamic strength endurance test (maximum number of repetitions for chest and leg press exercise at 30 - 35 % and 100 - 110 % of body mass, respectively) and a sit-stand test. Quality of life was assessed using the European Organization for Research and Treatment of Cancer QLQ-C30 (EORTC-C30) questionnaire. In response to training, QOL, VO2peak (mean 3.9 ml/kg/min; 95 % CI, 0.93, 6.90) performance in leg press (17.9 kg; 95 % CI, 12.8, 22.4) and sit-stand test (- 0.67 s; 95 % CI, - 0.52, - 1.2) improved (p < or = 0.05). We observed no significant changes in the control group. Combined cardiorespiratory and resistance training, even of very brief duration, improves the QOL and the overall physical fitness of women breast cancer survivors.