Extended Driving Impairs Nocturnal Driving Performances

Though fatigue and sleepiness at the wheel are well-known risk factors for traffic accidents, many drivers combine extended driving and sleep deprivation. Fatigue-related accidents occur mainly at night but there is no experimental data available to determine if the duration of prior driving affects driving performance at night. Participants drove in 3 nocturnal driving sessions (3–5am, 1–5am and 9pm–5am) on open highway. Fourteen young healthy men (mean age [±SD] = 23.4 [±1.7] years) participated Inappropriate line crossings (ILC) in the last hour of driving of each session, sleep variables, self-perceived fatigue and sleepiness were measured. Compared to the short (3–5am) driving session, the incidence rate ratio of inappropriate line crossings increased by 2.6 (95% CI, 1.1 to 6.0; P<.05) for the intermediate (1–5am) driving session and by 4.0 (CI, 1.7 to 9.4; P<.001) for the long (9pm–5am) driving session. Compared to the reference session (9–10pm), the incidence rate ratio of inappropriate line crossings were 6.0 (95% CI, 2.3 to 15.5; P<.001), 15.4 (CI, 4.6 to 51.5; P<.001) and 24.3 (CI, 7.4 to 79.5; P<.001), respectively, for the three different durations of driving. Self-rated fatigue and sleepiness scores were both positively correlated to driving impairment in the intermediate and long duration sessions (P<.05) and increased significantly during the nocturnal driving sessions compared to the reference session (P<.01). At night, extended driving impairs driving performances and therefore should be limited

Role of monocarboxylate transporters in human cancers : state of the art

Monocarboxylate transporters (MCTs) belong to the SLC16 gene family, presently composed by 14 members. MCT1-MCT4 are proton symporters, which mediate the transmembrane transport of pyruvate, lactate and ketone bodies. The role of MCTs in cell homeostasis has been characterized in detail in normal tissues, however, their role in cancer is still far from understood. Most solid tumors are known to rely on glycolysis for energy production and this activity leads to production of important amounts of lactate, which are exported into the extracellular milieu, contributing to the acidic microenvironment. In this context, MCTs will play a dual role in the maintenance of the hyper-glycolytic acidresistant phenotype of cancer, allowing the maintenance of the high glycolytic rates by performing lactate efflux, and pH regulation by the co-transport of protons. Thus, they constitute attractive targets for cancer therapy, which have been little explored. Here we review the literature on the role of MCTs in solid tumors in different locations, such as colon, central nervous system, breast, lung, gynecologic tract, prostate, stomach, however, there are many conflicting results and in most cases there are no functional studies showing the dependence of the tumors on MCT expression and activity. Additional studies on MCT expression in other tumor types, confirmation of the results already published as well as additional functional studies are needed to deeply understand the role of MCTs in cancer maintenance and aggressiveness

Evaluation of behavioral states among morning and evening active healthy individuals

The Horne-Östberg questionnaire partly covers some factors that may be important determinants of peak time and characterize patterns of behavior. We conducted a study for the evaluation of self-reported behavioral states (hunger sensation, availability for study, physical exercise, solving daily problems, and time preferences) as expressions of underlying cyclic activity. Three hundred and eighteen community subjects without history of medical, psychiatric, or sleep disorders were evaluated in a cross-sectional design. A self-report about daily highest level of activity was used to categorize individuals into morning, evening, and indifferently active. Time-related behavioral states were evaluated with 23 visual analog questions. The responses to most analogic questions were significantly different between morning and evening active subjects. Logistic regression analysis identified a group of behaviors more strongly associated with the self-reported activity pattern (common wake up time, highest subjective fatigue, as well as wake up, bedtime, exercise and study preferences). These findings suggested that the patterns of activity presented by normal adults were related to specific common behavioral characteristics that may contribute to peak time

Assessing the Value of Weight Loss Among Primary Care Patients

BACKGROUND: Modest weight loss of 10% of baseline weight is beneficial and achievable for overweight and obese patients. However, whether primary care patients value modest weight loss is unclear. OBJECTIVE: To quantify the value patients place on modest weight loss. DESIGN: Cross-sectional telephone survey. SETTING: Patients at a large hospital-based primary care practice. PARTICIPANTS: Three hundred sixty-five primary care patients (60% response rate). MEASUREMENTS: Utilities or value for weight loss estimated from willingness to risk death or trade time in exchange for losing different levels of weight (weight loss in pounds equivalent to a 5%, 10%, and 20% reduction in initial weight or to achieve a body mass index [BMI] of 25 kg/m2) using the standard gamble and time tradeoff formats. RESULTS: Of respondents, 15% of overweight (BMI, 25 to 29.9 kg/m2) and 42% of obese patients (BMI ≥ 30 kg/m2) believed they needed to lose more than 10% of their weight to derive any health benefits. However, 18% of overweight and 33% of obese patients were willing to risk death to lose 10% of their weight. Patients with higher BMI valued higher degrees of weight loss. Among the overall sample, the utilities derived using standard gamble were 0.95 for current weight, 0.96 for 5% weight loss, 0.97 for 10% weight loss, and 0.98 for 20% weight loss; among obese patients, utilities were 0.88, 0.91, 0.93, and 0.96, respectively. Utilities derived using time tradeoff were lower but correlated with utilities derived from standard gamble. Utilities did not vary by education, gender, race, having comorbidities, or smoking. CONCLUSIONS: Many primary care patients value modest weight loss. The value placed on loss of 10% body weight among obese patients where utility improved from 0.88 to 0.93 is similar to recovery from major depression. Nevertheless, the majority of patients still do not highly value modest weight loss. Clinicians should emphasize the health benefits of modest weight loss when counseling about weight