Chapter Nanopatterned Surfaces for Biomedical Applications

Optical physic

Changes in Plasma Potassium During Graded Aerobic Exercise and Two Hours of Recovery

Plasma potassium increases with exercise intensity. Subjects (n=8) were monitored for changes in plasma potas-sium while exercising at progressively increasing steady-state intensities and for two hours of recovery. Plasma po-tassium was significantly increased at 100% of VO2peak compared to 20% and 40% (p<0.01). Plasma potassium at 60 and 120 minutes of recovery from exercise was significantly higher than 6 minutes post exercise (p<0.015). These results support the supposition that high-intensity exercise may lead to hyperkalemia, and also indicates that in-creases in [K + ] occur up to two hours after the cessation of exercise, a newly reported phenomenon. Although, high levels of plasma potassium are known to cause cardiac abnormalities and related events, exercise induced changes in normal healthy adults are not currently believed to have clinical implications

Impact of gestational treatment or prenatal cocaine exposure on early postpartum oxytocin synthesis and receptor binding

Prior research reported decreased oxytocin levels in specific brain regions and disruptions in maternal care following gestational cocaine treatment in rats. Similarly, prenatal exposure to cocaine impaired maternal behavior in adulthood, but this was not associated with oxytocin level disruptions. To determine if cocaine alters other aspects of the oxytocin system, oxytocin mRNA transcription and receptor binding were examined on postpartum day two in relevant brain regions following gestational treatment with, or prenatal exposure to, either cocaine or saline. Results indicated an increase in oxytocin mRNA levels in the paraventricular nucleus of dams treated with cocaine gestationally with no group differences in brain regions dependent upon prenatal exposure. No significant differences in receptor binding were found in any region examined for either group of dams. These findings suggest that cocaine affects multiple aspects of the oxytocin system in the early postpartum that could be associated with altered maternal behavior

A Rodent Model of Cocaine’s Effect on the Mother Infant Dyad

Cocaine abuse by women is correlated with a high incidence of child neglect and abuse, and young children prenatally exposed to cocaine show early signs of neurobehavioral stress, including excessive and high-pitched crying, increased state lability, decreased responsiveness to caregivers, stress-related behavioral differences, and poor social development. Research on the effects of in utero cocaine exposure on early brain development and behaviors that elicit maternal care is relatively sparse. Using a rat model of cocaine-induced maternal neglect, the goals of this dissertation were to first examine the impact of cocaine on the interactions between rodent mothers and pups and to determine whether specific elements of pup behavior may be altered by prenatal cocaine exposure to influence these interactions. The first experiment described here examined whether the effects of cocaine-induced maternal neglect extend intergenerationally and if the rearing environment (neglectful or nurturing) can alter the effects of prenatal cocaine on offspring. Results from this study indicated that cocaine-exposed pups elicited reduced maternal care from their rearing mother, regardless of that mother's drug history. Since rodent mothers attend to the specific stimuli of pups, such as vocalizations, body temperature, and olfactory cues, the next study was completed to examine the impact of cocaine on the cues utilized by pups to elicit care. Results from these studies suggested that prenatal cocaine-exposure influences thermoregulation and vocalization in the early postnatal period, either directly or perhaps in combination with the indirect effects of prenatal stress and malnutrition. A third experiment was also conducted to examine a number of chemicals in pup urine that may contribute to the elicitation of maternal care. The only chemicals of interest that were detectable in urine were cocaine and its major metabolites, found in samples through postnatal day 3, suggesting that cocaine may still be pharmacologically relevant into the postpartum period and may influence the taste and smell of pup urine, thus potentially influencing the maternal response. Together, this dissertation suggests that cocaine impacts both members of the mother-infant dyad to alter these important social interactions, and highlights numerous targets of prenatal cocaine on infant behavior for further study.Doctor of Philosoph

Exercise-Induced Glycogen Reduction Increases Muscle Activity

International Journal of Exercise Science 9(3): 336-346, 2016. Intramuscular glycogen stores are an important energy source during extended bouts of strenuous exercise. A substantial reduction in glycogen could influence neural muscular drive and result in a decreasing quality of exercise performance and potentially increased injury rates. The aim of this study was to examine the effect of glycogen reduction on motor drive as determined by the surface electromyogram (EMG) amplitude and median frequency during a cycling graded exercise test. Eight trained cyclists performed a discontinuous cycling graded exercise test to exhaustion under both normal and glycogen reduced conditions. EMG was collected from the vastus lateralis. Repeated measures regression models indicated that EMG amplitudes were elevated at cycling workloads higher than 196 Watts and metabolic workloads higher than 40.8 ml/kg/min, corresponding to 77% VO2max. There was no effect of increases in workload or glycogen reduction on EMG median frequency. Changes in mechanical and metabolic workload had a substantial effect on EMG amplitude (Cohen’s f2 = 0.227 and 0.247, respectively), but not median frequency (Cohen’s f2 = 0.026 and 0.033, respectively). Thus, EMG amplitude is a more effective and reliable measure to examine changes in motor drive during variable workload conditions and metabolic perturbations. The results suggest that healthy glycogen reduced humans require higher levels of muscle activity in order to attain a given mechanical and metabolic workload. This may affect the long term performance of professional and military athletes who need to be able to perform at a high level for extended periods of activity

Statins in the prevention and treatment of heart failure: a review of the evidence

Purpose of Review: We summarize the best evidence for statins in the prevention and treatment of heart failure. Recent Findings: In patients with cardiovascular risk factors or established atherosclerotic cardiovascular disease (but without heart failure), statins reduce the risk of incident heart failure—mainly by preventing myocardial infarction although an additional benefit from reducing myocardial ischemia cannot be excluded. However, in patients with established heart failure, statins do not reduce the risk of cardiovascular death, which is mainly caused by pump failure and ventricular arrhythmias. Retrospective analyses, however, suggest that statins may reduce the rate of heart failure hospitalization and atherosclerotic events (which are proportionately much less common in these patients than heart failure hospitalization or death). Summary: Statin therapy should probably be continued in patients with coronary artery disease developing heart failure, although the weak evidence and small benefit may not justify the use of this treatment in very elderly patients with a short life expectancy and in which polypharmacy is a problem

A novel device for the calibration of sonic and ultrasonic recording transducers

Recently, there has been an increase in the analysis of animal vocalizations in behavioral neuroscience as a social cue or indicator of neurological integrity. Despite the multitude of researchers examining vocalizations in a variety of species, no inexpensive, tunable devices currently exist to calibrate the amplification applied to such vocalizations before data are collected. Many commercially available recording systems have analogue adjustments for gain, but such methods are notoriously unreliable and highly variable. Without a consistent level of gain, the amplitudes of recorded acoustic signals cannot be reliably compared. Here, we describe an apparatus designed to fulfill this need, which we have labeled the Calibration Unit for Recording Transducers (CURT). To maximize application to various fields, its emitted frequency and amplitude are tunable to output frequencies in both human-sonic (20 Hz – 20 kHz) and human-ultrasonic ranges (20–100 kHz). Additionally, it is a portable (weighing approximately 180 g), customizable, stand-alone unit, and fits a variety of microphone connector types. The CURT is also relatively low cost to build (under 250.00 USD), thereby making such a device available to as many researchers as possible in animal behavior and neuroscience

Questions of the right and the good: metaethics and anthropology

Questions of the right and the good have been variously recognised by anthropologists as key to understanding human action and behaviour since the early days of the discipline, with the influential recent ‘ethical turn’ perhaps the most obvious example (Mattingly and Throop, 2018). Here, the authors – who together founded the Social Science and Ethics Group at the University of Sussex – reflect on how their own fieldwork led them to engage with metaethics, and how doing so advanced their understanding of their ethnographic material, anthropological theory, and their own professional ethics. The three cases draw on fieldwork in Nicaragua, Bolivia, and China

Prevalence of prediabetes and undiagnosed diabetes in patients with HFpEF and HFrEF and associated clinical outcomes

Purpose: The prevalence and consequences of prediabetic dysglycemia and undiagnosed diabetes is unknown in patients with heart failure (HF) and preserved ejection fraction (HFpEF) and has not been compared to heart failure and reduced ejection fraction (HFrEF). Methods: We examined the prevalence and outcomes associated with normoglycemia, prediabetic dysglycemia and diabetes (diagnosed and undiagnosed) among individuals with a baseline glycated hemoglobin (hemoglobin A1c, HbA1c) measurement stratified by HFrEF or HFpEF in the Candesartan in Heart failure Assessment of Reduction in Mortality and morbidity programme (CHARM). We studied the primary outcome of HF hospitalization or cardiovascular (CV) death, and all-cause death, and estimated hazard ratios (HR) by use of multivariable Cox regression models. Results: HbA1c was measured at baseline in CHARM patients enrolled in the USA and Canada and was available in 1072/3023 (35%) of patients with HFpEF and 1578/4576 (34%) patients with HFrEF. 18 and 16% had normoglycemia (HbA1c &lt; 6.0), 20 and 22% had prediabetes (HbA1c 6.0–6.4), respectively. Finally among patients with HFpEF 22% had undiagnosed diabetes (HbA1c &gt; 6.4), and 40% had known diabetes (any HbA1c), with corresponding prevalence among HFrEF patients being 26 and 35%. The rates of both clinical outcomes of interest were higher in patients with undiagnosed diabetes and prediabetes, compared to normoglycemic patients, irrespective of HF subtype, and in general higher among HFrEF patients. For the primary composite outcome among HFpEF patients, the HRs were 1.02 (95% CI 0.63–1.65) for prediabetes, HR 1.18 (0.75–1.86) for undiagnosed diabetes and 2.75 (1.83–4.11) for known diabetes, respectively, p value for trend across groups &lt; 0.001. Dysglycemia was also associated with worse outcomes in HFrEF. Conclusions: These findings confirm the remarkably high prevalence of dysglycemia in heart failure irrespective of ejection fraction phenotype, and demonstrate that dysglycemia is associated with a higher risk of adverse clinical outcomes, even before the diagnosis of diabetes and institution of glucose lowering therapy in patients with HFpEF as well as HFrEF