Possible role of caffeine in nicotine use onset among early adolescents: Evidence from the Young Mountaineer Health Study Cohort.

BACKGROUND: Preventing nicotine use onset among children and youth is an important public health goal. One possible contributor that has received little empirical investigation is caffeine use. The goal of this study was to examine the possible contribution of caffeine to nicotine onset during early adolescence. METHODS: We used data from the Young Mountaineer Health Study Cohort. Survey data were collected from 1,349 (response rate: 80.7%) 6th grade students (mean age at baseline 11.5 years) in 20 middle schools in West Virginia during the fall of 2020 and spring of 2021. We limited our analyses to students reporting never having used any form of nicotine at baseline. Logistic regression was employed in analyses. RESULTS: Approximately 8% of participants reported having used nicotine at least once between baseline and the follow-up, and 4.7% reported solely using electronic nicotine delivery systems (ENDS) and no other forms of nicotine. In multivariable analyses, we controlled for many environmental, social, and behavioral variables known to influence nicotine use such as alcohol use, peer substance use, and perceived access to nicotine. We formulated our main independent variable, caffeine consumption, as continuous deciles. Any nicotine use, as well as ENDS use only at follow-up, were modeled as dependent variables. Caffeine was significantly associated with nicotine use in both models with ORs of 1.15 (1.04-1.27) and 1.13 (1.00-1.28). CONCLUSIONS: Caffeine consumption among 6th grade non-nicotine users was associated with nicotine use at approximately 6-months follow-up.

The supplementation of a prebiotic improves the microbial community in the gut and the skin of Atlantic salmon (Salmo salar).

Aquaculture growth is hindered by an increasing number of challenges, primarily infectious diseases and inappropriate or unsustainable fish nutrition. Hence it is critical to develop novel prevention strategies to minimise infectious diseases and pharmaceutical interventions. Nutritional challenges and the health of the fish could be improved by managing their microbial communities. Microbiomes can play a crucial role in fish physiology, particularly in digestion, by metabolizing largely indigestible feed components for the host or synthesis essential micronutrients. Beyond their nutritional role, microbiomes are considered the first line of defence against pathogens. In this study, a novel prebiotic mix (Selectovit), composed of 1,3/1,6-beta glucans, mannan-oligosaccharides, nucleic acids, nucleotides, medium chain fatty acids and single chain fatty acids, was tested at different inclusion levels (0.0; 0.5; 1.0; 2.0 g/kg) in the diet of Atlantic salmon (Salmo salar). Using experimental feed trials and 16 S rRNA microbiome profiling, the impact of the prebiotic blend on fish growth and microbial community within both the gastrointestinal tract and the skin was assessed. Overall, the supplement showed no significant impact on growth. However, we clearly demonstrate that the prebiotic can significantly manipulate the microbial community of the distal intestine and the skin. Several potential beneficial bacteria such as Bacillus and Mycoplasma spp. were significantly more abundant in the prebiotic-fed groups compared to the control. In contrast, putative pathogenic bacteria were less abundant in the salmon fed the prebiotic blend. Interestingly, the supplement induced more changes in the skin than in the gut. There is growing evidence in fish for highly complex interactions between the microbial communities of the digestive system and external mucosa, and with the host immune system. Further research in this field could lead to the creation of novel bacterial biomarkers and new non-invasive strategies for fish digestive health monitoring.

Risk and Resilience Pathways, Community Adversity, Decision-making, and Alcohol Use Among Appalachian Adolescents: Protocol for the Longitudinal Young Mountaineer Health Study Cohort.

BACKGROUND: Alcohol use impairs psychosocial and neurocognitive development and increases the vulnerability of youth to academic failure, substance use disorders, and other mental health problems. The early onset of alcohol use in adolescents is of particular concern, forecasting substance abuse in later adolescence and adulthood. To date, evidence suggests that youth in rural areas are especially vulnerable to contextual and community factors that contribute to the early onset of alcohol use. OBJECTIVE: The objective of the Young Mountaineer Health Study is to investigate the influence of contextual and health behavior variables on the early onset of alcohol use among middle school-aged youth in resource-poor Appalachian rural communities. METHODS: This is a program of prospective cohort studies of approximately 2200 middle school youth from a range of 20 rural, small town, and small city (population <30,000) public schools in West Virginia. Students are participating in 6 waves of data collection (2 per year) over the course of middle school (sixth to eighth grades; fall and spring) from 2020 to 2023. On the basis of an organizational arrangement, which includes a team of local data collection leaders, supervising contact agents in schools, and an honest broker system to deidentify data linked via school IDs, we are able to collect novel forms of data (self-reported data, teacher-reported data, census-linked area data, and archival school records) while ensuring high rates of participation by a large majority of youth in each participating school. RESULTS: In the spring of 2021, 3 waves of student survey data, 2 waves of data from teachers, and a selection of archival school records were collected. Student survey wave 1 comprised 1349 (response rate 80.7%) participants, wave 2 comprised 1649 (response rate 87%) participants, and wave 3 comprised 1909 (response rate 83.1%) participants. The COVID-19 pandemic has had a negative impact on the sampling frame size, resulting in a reduced number of eligible students, particularly during the fall of 2020. Nevertheless, our team structure and incentive system have proven vitally important in mitigating the potentially far greater negative impact of the pandemic on our data collection processes. CONCLUSIONS: The Young Mountaineer Health Study will use a large data set to test pathways linking rural community disadvantage to alcohol misuse among early adolescents. Furthermore, the program will test hypotheses regarding contextual factors (eg, parenting practices and neighborhood collective efficacy) that protect youth from community disadvantage and explore alcohol antecedents in the onset of nicotine, marijuana, and other drug use. Data collection efforts have been successful despite interruptions caused by the COVID-19 pandemic in 2020 and 2021. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/40451.

Caffeine consumption and onset of alcohol use among early adolescents.

Preventing or delaying the onset of alcohol use among children and youth is an important public health goal. One possible factor in alcohol use onset among early adolescents is caffeine. The aim of this study was to assess the possible contribution of caffeine to the onset of alcohol use during early adolescence. We used data from the Young Mountaineer Health Study Cohort. Survey data were collected from 1349 (response rate: 80.7%) 6th grade students (mean age at baseline 11.5 years) in 20 middle schools in West Virginia during the fall of 2020, and again approximately 6 months later in spring of 2021. We limited our analyses to students reporting never having used any form of alcohol at baseline. Logistic regression was employed in multivariable analyses and both Odds Ratios and Relative Risks reported. At follow-up, almost 14% of participants reported having consumed alcohol at least once and 57% used caffeine of 100 mg + daily. In multivariable analyses we controlled for social and behavioral variables known to impact tobacco use. Caffeine use was operationalized as a three-level factor: no use, <100 mg per day, and 100 + mg per day, with the latter being the approximate equivalent of the minimum of a typical cup of coffee or can of energy drink. Caffeine use of 100 mg + per day was significantly related to alcohol use at 6-months follow-up (OR: 1.79, RR: 1.56, p = .037). We conclude that caffeine consumption among 11-12-year-old adolescents may be a factor in early onset of alcohol use.

Palatability Enhancement Potential of Hermetia illucens Larvae Protein Hydrolysate in Litopenaeus vannamei Diets.

Marine feed ingredients derived from cephalopods (e.g., squid) and crustaceans (e.g., krill) are commercially used to improve the palatability of shrimp diets. Increase in global demand for shrimps has resulted in overfishing of these marine organisms and is a matter of concern. Insect protein hydrolysate could be a sustainable alternative for the possible replacement of these marine feed ingredients. During this study, four formulations: diet A (control: not containing any palatability enhancer), diet B (containing squid meal and krill oil), diet C (containing 1% insect protein hydrolysate), and diet D (containing 2% insect protein hydrolysate) were tested for (1) time required by first subject to begin feeding (time to strike) and (2) palatability in Litopenaeus vannamei. Additionally, the chemical composition of all four diet formulations was also analyzed. Results indicate that all diets had similar crude composition. The major essential amino acids in all diets were leucine and lysine, whereas eicosapentaenoic acid was the major omega-3 fatty acid in all diets. There were no significant differences between the mean time to strike for all the tested formulations. Palatability of tested formulations was found in the following order: diet D > diet C > diet B = diet A (p < 0.05), indicating that addition of squid meal and krill oil has no effect on palatability in comparison to control, whereas inclusion of insect protein hydrolysates significantly improves the palatability of formulations. Palatability enhancement potential of insect protein hydrolysate could be attributed to the high free amino acid content and water solubility in comparison to squid meal.

Protein over-expression in Escherichia coli triggers adaptation analogous to antimicrobial resistance.

BACKGROUND: The E. coli pET system is the most widely used protein over-expression system worldwide. It relies on the assumption that all cells produce target protein and it is generally believed that integral membrane protein (IMP) over-expression is more toxic than their soluble counterparts. RESULTS: Using GFP-tagged proteins, high level over-expression of either soluble or IMP targets results in > 99.9% cell loss with survival rate of only < 0.03%. Selective pressure generates three phenotypes: large green, large white and small colony variants. As a result, in overnight cultures, ~ 50% of the overall cell mass produces no protein. Genome sequencing of the phenotypes revealed genomic mutations that causes either the loss of T7 RNAP activity or its transcriptional downregulation. The over-expression process is bactericidal and is observed for both soluble and membrane proteins. CONCLUSIONS: We demonstrate that it is the act of high-level over-expression of exogenous proteins in E. coli that sets in motion a chain of events leading to > 99.9% cell death. These results redefine our understanding of protein over-production and link it to the adaptive survival response seen in the development of antimicrobial resistance.

Adolescent caffeine consumption and aggressive behavior: A longitudinal assessment.

Background: Adolescent caffeine consumption has been linked to aggressive behaviors, although no longitudinal tests have been reported to date. The purpose of this study was to test the longitudinal relations between daily adolescent caffeine consumption and aggressive behaviors. Methods: Two waves of survey data collected 12 months apart in the spring of 2018 and 2019, from the 2004 birth cohort in the Icelandic LIFECOURSE study, were analyzed using structural equation modeling (N = 2,278). Both direct and mediated models were employed. Results: Caffeine use at time 1 (T1) was associated with aggressive behavior at time 2 (T2) (ß = .12, p < .001) independent of aggressive behavior at T1. A considerable added relation was observed between caffeine at T1 and aggressive behavior at T2 via indirect (i.e., mediated) effects of aggressive behavior at T1 (standardized ß = .20, p < .001). Over 64% of the standardized total effect (ß = .31) observed between caffeine at T1 and aggressive behavior at T2 was due to mediation. Conclusion: Adolescent caffeine consumption forecasts aggressive behaviors. Caffeine use at T1 increased the likelihood of self-reported aggressive behaviors 12 months later irrespective of level of reported aggressive behavior at T1 while controlling for common confounders.

Maternal caffeine consumption and pregnancy outcomes: a narrative review with implications for advice to mothers and mothers-to-be.

OBJECTIVES: Caffeine is a habit-forming substance consumed daily by the majority of pregnant women. Accordingly, it is important that women receive sound evidence-based advice about potential caffeine-related harm. This narrative review examines evidence of association between maternal caffeine consumption and negative pregnancy outcomes, and assesses whether current health advice concerning maternal caffeine consumption is soundly based. METHODS: Database searches using terms linking caffeine and caffeinated beverages to pregnancy outcomes identified 1261 English language peer-reviewed articles. Screening yielded a total of 48 original observational studies and meta-analyses of maternal caffeine consumption published in the past two decades. The articles reported results for one or more of six major categories of negative pregnancy outcomes: miscarriage, stillbirth, low birth weight and/or small for gestational age, preterm birth, childhood acute leukaemia, and childhood overweight and obesity. RESULTS: Of 42 separate sets of findings reported in 37 observational studies, 32 indicated significantly increased caffeine-related risk and 10 suggested no or inconclusive associations. Caffeine-related increased risk was reported with moderate to high levels of consistency for all pregnancy outcomes except preterm birth. Of 11 studies reporting 17 meta-analyses, there was unanimity among 14 analyses in finding maternal caffeine consumption to be associated with increased risk for the four outcome categories of miscarriage, stillbirth, low birth weight and/or small for gestational age, and childhood acute leukaemia. The three remaining meta-analyses were also unanimous in reporting absence of a reliable association between maternal caffeine consumption and preterm birth. No meta-analyses were identified for childhood overweight and obesity, although four of five original observational studies reported significant associations linking maternal caffeine consumption to that outcome category. CONCLUSIONS: The substantial majority finding from observational studies and meta-analyses is that maternal caffeine consumption is reliably associated with major negative pregnancy outcomes. Reported findings were robust to threats from potential confounding and misclassification. Among both observational studies and meta-analyses, there were frequent reports of significant dose-response associations suggestive of causation, and frequent reports of no threshold of consumption below which associations were absent. Consequently, current evidence does not support health advice that assumes 'moderate' caffeine consumption during pregnancy is safe. On the contrary, the cumulative scientific evidence supports pregnant women and women contemplating pregnancy being advised to avoid caffeine.

Disclosing conflict of interest does not mitigate healthcare bias and harm: It is time to sever industry ties.

Disclosing conflict of interest is widely believed to mitigate bias and harm from industry entanglement in healthcare research, education and practice. However, evidence is lacking of disclosure-related mitigation. Radical and extensive severing of industry ties to health care is necessary to curtail industry-related bias and harm.

Can public financing of the private sector defeat antimicrobial resistance?

Public financing to incentivise private sector innovation in antimicrobial pharmaceuticals is believed by many to be necessary to defeat growing threats from antimicrobial resistance. Large cash incentives from the public sector are said to be essential to stimulate 'normal' market forces capable of unleashing much-needed innovation. However, there is little evidence to suggest that lack of innovation in drug development is peculiar to antimicrobials or that current deficits in the supply of antimicrobials is due to unique inefficiencies in the antimicrobial market. Neither the history of drug development in general nor of antimicrobial innovation in particular supports economic interventions intended to stimulate private sector supply of new antimicrobials. On the contrary, public underwriting of the private sector, which by definition is compelled to prioritise profit, risks dire consequences for future global health.

The Vegetation Red Edge Biosignature Through Time on Earth and Exoplanets.

The high reflection of land vegetation in the near-infrared, the vegetation red edge (VRE), is often cited as a spectral biosignature for surface vegetation on exoplanets. The VRE involves only a few percentage change in reflectivity for a disk-integrated observation of present-day Earth. Here we show that the strength of Earth's VRE has increased over the past ∼500 million years of land plant evolution and may continue to increase as solar luminosity increases and the planet warms, until either vegetation coverage is reduced, or the planet's atmosphere becomes opaque to light reflected off the surface. Early plants such as mosses and liverworts, which dominated the land 500-400 million years ago, produce a weaker VRE, approximately half as strong as that of modern vegetation. We explore how the changes in land plants, as well as geological changes such as ice coverage during ice ages and interglacial periods, influence the detectability of the VRE through Earth's geological past. Our results show that the VRE has varied through the evolutionary history of land plants on Earth and could continue to change into the future if hotter climate conditions became dominant, encouraging the spread of vegetation. Our findings suggest that older and hotter Earth-like planets are good targets for the search for a VRE signature. In addition, hot exoplanets and dry exoplanets with some water could be the best targets for a successful vegetation biosignature detection. As well as a strong red edge, lower cloud fractions and low levels of atmospheric water vapor on such planets could make it easier to detect surface features in general.

Adolescent habitual caffeine consumption and hemodynamic reactivity during rest, psychosocial stress, and recovery.

OBJECTIVE: Most adolescents regularly consume caffeine. Whereas observational studies have suggested that coffee may be cardio-protective, pharmacological experimentation with adults shows that caffeine at dietary doses increases blood pressure, thereby implicating regular caffeine consumption as a potential source of harm for cardiovascular health. The present study was in response to the dearth of caffeine research among younger consumers. It was hypothesised that compared to the consumption of little or no caffeine, adolescents who habitually consume caffeine have overall higher blood pressure and increased vascular resistance. METHOD: Using a quasi-experimental design, continuous measurements of blood pressure, cardiac output, and total peripheral resistance were taken non-invasively from adolescents (n = 333) aged 14-15 years and 18-19 years who reported "low", "moderate", or "high" levels of caffeine intake. Measurements were conducted when participants generally had negligible or low systematic caffeine levels while at rest, during stress, and during recovery from stress. RESULTS: Whereas habitual caffeine consumption did not predict blood pressure level, higher caffeine intake was associated with modestly increased vascular resistance during all phases of the experiment (i.e., at rest, during stress, and during recovery from stress). CONCLUSIONS: Present findings are important because they suggest that early exposure to caffeine may lead to persistent increases in vascular resistance, which in turn is an acknowledged risk factor for the development of hypertension. These results highlight the need for further studies of adolescents to determine the robustness of any persistent caffeine-related hemodynamic effects, and the implications such effects could have for long-term cardiovascular health.

Does early exposure to caffeine promote smoking and alcohol use behavior? A prospective analysis of middle school students.

BACKGROUND AND AIMS: Despite the negative consequences associated with caffeine use among children and youth, its use is increasingly widespread among middle school students. Cross-sectional studies reveal links between caffeine and other substance use. The potential for caffeine use to confer increased vulnerability to substance use, however, has not been investigated using prospective designs. We hypothesized that caffeine use at baseline would be associated positively with increased alcohol use, drunkenness, smoking and e-cigarette use. DESIGN: Prospective cohort study with 12 months separating baseline from follow-up. SETTING: West Virginia, USA. PARTICIPANTS: Middle school students (6th and 7th grades; n = 3932) in three West Virginia (WV) counties provided data at baseline and follow-up 12 months later. MEASUREMENTS: Youth self-reported their use of caffeine from multiple sources (e.g. soda, energy drinks, coffee and tea), cigarette smoking, electronic cigarette use, alcohol use and drunkenness. FINDINGS: Cross-lagged path models for individual substance use categories provided a good fit to the data. Controlling for demographic variables and other substance use at baseline, caffeine at time 1 (T1) was associated positively with T2 cigarette smoking (ß = 0.27, P = 0.001), e-cigarette use (ß = 0.21, P = 0.001), alcohol use (ß = 0.17, P = 0.001) and drunkenness (ß = 0.15, P = 0.001). Conversely, non-significant relations emerged between three of four substances at T1 and caffeine at T2. Positive relations were found between e-cigarette use at T1 and caffeine use at T2 (ß = 0.07, P = 0.006). These findings were supported by an omnibus model with all substances included. Specifically, significant relations were observed between caffeine at T1 and all substance use outcomes at T2, whereas no significant relations were observed between substance use and caffeine over time. CONCLUSIONS: Caffeine may promote early use of other types of substances among middle school-aged adolescents.

Are coffee's alleged health protective effects real or artifact? The enduring disjunction between relevant experimental and observational evidence.

BACKGROUND: There is a large corpus of observational evidence claiming that coffee is health protective and a similarly large corpus of experimental psychopharmacological evidence to suggest that habitual caffeine consumption may be harmful to health. AIM: The purpose of this study was to examine the disjunction between observational and experimental findings with specific reference to the implications of coffee/caffeine consumption for elevated blood pressure, cardiovascular disease, type 2 diabetes and neurodegenerative disease. METHOD: Illustrative recent major reviews alleging health protective effects from coffee consumption were examined in light of findings from relevant experimental studies of caffeine. FINDINGS: Decades-long coffee consumption is but one of countless lifestyle variables that may benefit or harm health. Contradictions concerning the implications of coffee/caffeine consumption for health between observational and experimental research are attributable mostly to poor control over potential confounders in observational studies. CONCLUSION: When considered in the context of experimental evidence concerning caffeine's known pharmacological actions, there is reason to be sceptical about observational findings alleging health-protective effects from coffee consumption. Long-term randomised trials are needed to end the enduring interpretative disjunction between observational and experimental evidence concerning coffee/caffeine consumption and health.

Sleep restriction undermines cardiovascular adaptation during stress, contingent on emotional stability.

Sleep loss is associated with increased cardiovascular disease, but physiological mechanisms accounting for this relationship are largely unknown. One possible mechanism is that sleep restriction exerts effects on cardiovascular stress responses, and that these effects vary between individuals. Emotional stability (ES) is a personality trait pertinent to sleep restriction and stress responding. However, no study to date has explored how ES and sleep-restriction interactively affect cardiovascular stress responses or processes of adaptation during stress. The present study sought to investigate the association between ES and impact of sleep restriction on cardiovascular function during stress, with particular regard to the trajectory of cardiovascular function change across time. Ninety female university students completed a laboratory vigilance stress task while undergoing continuous cardiovascular (SBP, DBP, HR, SV, CO, TPR) monitoring, after either a night of partial sleep restriction (40% of habitual sleep duration) or a full night's rest. Individuals high in ES showed stable and adaptive cardiovascular (SBP, SV, CO) responses throughout stress exposure, regardless of sleep. In contrast, individuals low in ES exhibited cardiovascular adaptation during stress exposure while rested, but disrupted adaption while sleep-restricted. These findings suggest that sleep-restriction undermines healthful cardiovascular adaptation to stress for individuals low in ES.

Stress among Parents of Children with and without Autism Spectrum Disorder: A Comparison Involving Physiological Indicators and Parent Self-Reports.

Parents of children with Autism Spectrum Disorder (ASD) have been reported as experiencing higher levels of stress and poorer physical health than parents of typically developing children. However, most of the relevant literature has been based on parental self-reports of stress and health. While research on physiological outcomes has grown in recent years, gaps still exist in our understanding of the physiological effects, if any, of stress related to parenting a child with ASD. The present study compared parent-reported stress, anxiety, and depression, as well as selected physiological measures of stress (i.e., cortisol, alpha-amylase, and ambulatory blood pressure and heart rate) between matched groups of parents of children with (N = 38) and without (N = 38) ASD. Participants completed questionnaires, collected saliva samples for the purpose of measuring cortisol and alpha-amylase, and wore an ambulatory blood pressure monitor for 24 h. Parents of children with ASD reported significantly higher levels of parental distress, anxiety, and depression than parents of typically developing children. Parent-reported distress, anxiety, depression, and health were not correlated with physiological measures. With the exception that parents of children with ASD had significantly lower cortisol levels 30 min after waking, no other significant group differences were found for physiological measures. Parents of children with ASD reported significantly higher use of a number of adaptive coping strategies (e.g., emotional support) in comparison to parents of typically developing children. Results are discussed in the context of implications for future research directions, stress research, and practical implications for parental support.

Reviving Cochrane's contribution to evidence-based medicine: bridging the gap between evidence of efficacy and evidence of effectiveness and cost-effectiveness.

Throughout the quarter century since the advent of evidence-based medicine (EBM), medical research has prioritized 'efficacy' (i.e. internal validity) using randomized controlled trials. EBM has consistently neglected 'effectiveness' and 'cost-effectiveness', identified in the pioneering work of Archie Cochrane as essential for establishing the external (i.e. clinical) validity of health care interventions. Neither Cochrane nor other early pioneers appear to have foreseen the extent to which EBM would be appropriated by the pharmaceutical and medical devices industries, which are responsible for extensive biases in clinical research due to selective reporting, exaggeration of benefits, minimization of risks, and misrepresentation of data. The promise of EBM to effect transformational change in health care will remain unfulfilled until (i) studies of effectiveness and cost-effectiveness are pursued with some of the same fervour that previously succeeded in elevating the status of the randomized controlled trial, and (ii) ways are found to defeat threats to scientific integrity posed by commercial conflicts of interest.

Perceived social support predicts lower cardiovascular reactivity to stress in older adults.

The benefits of perceived social support for physical and psychological health are well-established. However, little research has explored associations between perceived social support and cardiovascular reactivity in older adults. This exploratory study recruited a sample of older adults (Mage=69years, SD=5.62) and examined quality and quantity of perceived social support as predictors of cardiovascular reactivity to laboratory-based stress (N=39 participants) and ambulatory cardiovascular activity in everyday life (n=28). The results suggest that quality, but not quantity, of perceived social support predicts reduced blood pressure reactivity to stress in the laboratory. Although quality of support was not associated with ambulatory blood pressure, results suggest that quantity of daily social support may be associated with higher ambulatory heart rate, but not with social contact during measurement. This preliminary study extends prior work on social support and cardiovascular function to a group of older adults in both laboratory and field settings. Challenges for much-needed future research in this area are discussed.