Search results for "Biophysics"
showing 10 items of 3515 documents
Atrial natriuretic peptide secretion during development of the rat supraoptic nucleus
2009
Since a relationship between atrial natriuretic peptide and oxytocin was recently demonstrated in the heart (Gutkowska et al., 1997), the aim of this study was to determine whether a relationship between the two peptides is present also in the rat hypothalamus. For this purpose, we measured ANP-ontogeny in the rat hypothalamus immunohistochemically and compared it with oxytocin-ontogeny which we previously studied. The results showed that the ANP-peptide and mRNA-ANP start at the 18th day of the fetal life. Our earlier data for oxytocin in the rat hypothalamus showed that only mRNA-oxytocin appeared the 18th day of foetal life (Farina Lipari et al., 2001); thus, at the 18th day of foetal li…
The effects of a calisthenics training intervention on posture, strength and body composition
2017
BACKGROUND: Calisthenics was a term used to define a generic set of body weight exercises. Such term is now used to define a world wide spread discipline based on body weight and gymnastics exercises.OBJECTIVE: The aim of this study was to administer a calisthenics training protocol and evaluate its effects on posture, strength and body composition in untrained individuals.METHODS: Twenty-eight male participants (24.2 +/- 4.2 years; 67.0 +/- 8.3 Kg; 173.3 +/- 5.2 cm) were divided into two groups, a Calisthenics based intervention group (SG) and a control group (CG). The SG exercised for 8 weeks. Each participant underwent a body composition analysis, a postural assessment, a handgrip test, …
EMG activities and plantar pressures during ski jumping take-off on three different sized hills
2001
Different profiles of ski jumping hills have been assumed to make the initiation of take-off difficult especially when moving from one hill to another. Neuromuscular adaptation of ski jumpers to the different jumping hills was examined by measuring muscle activation and plantar pressure of the primary take-off muscles on three different sized hills. Two young ski jumpers volunteered as subjects and they performed several trials from each hill (K-35 m, K-65 m and K-90 m) with the same electromyographic (EMG) electrode and insole pressure transducer set-up. The results showed that the differences in plantar pressure and EMGs between the jumping hills were smaller than expected for both jumper…
Effects of workload level on muscle recruitment in cycling
2014
AbstractPurpose. Despite the volume of studies addressing muscle activation during pedaling, it is unclear whether changes in workload level during cycling could dictate motor unit recruitment. The present study investigated the frequency content of lower limb muscle activation during submaximal workloads. Methods. Twelve male competitive cyclists pedaled at three workload levels: (1) maximum aerobic power output (PO
Effect of Soluble Interleukin-6 Receptor on Interleukin-6 Synthesis in Human Skin Fibroblasts
1996
Abstract In this study the ability of soluble interleukin-6 receptor (sIL-6R) to stimulate interleukin-6 (IL-6) synthesis in human fibroblasts is described. It was found that sIL-6R, in combination with endogenous or exogenous IL-6, markedly upregulated IL-6 synthesis. These data suggest that increased IL-6 production after stimulation by either interleukin-1 or tumor necrosis factor-α would result in complex formation with sIL-6R, rapid uptake, and further synthesis of this cytokine. Furthermore, it would explain the decrease in sIL-6R plasma levels observed in patients suffering from sepsis.
Sensorimotor training prior total knee arthroplasty and effects on functional outcome: A systematic review and meta-analysis.
2021
Abstract Background Altered muscle activation patterns and proprioception, loss of strength, and weight bearing asymmetries are common limitations after total knee arthroplasty, which can also affect balance. Therefore, preoperative sensorimotor training has been proposed to enhance surgical outcome. Research question Is preoperative sensorimotor training effective in improving functional outcome in patients undergoing total knee arthroplasty? Does preoperative sensorimotor training affect secondary outcomes such as balance, pain, and quality of life? Methods A systematic review and meta-analysis were conducted by searching PEDro, MEDLINE, Embase, Cochrane Library, and Scopus databases from…
Cholesterol as stabilizer of the oxytocin receptor
2002
AbstractThe function of the oxytocin receptor system is strongly dependent on steroids as demonstrated by several physiological studies. One key element of this dependence on steroids may be the interaction of cholesterol and the oxytocin receptor. In this study, we show that cholesterol stabilizes the solubilized human oxytocin receptor against thermal inactivation and proteolytic degradation. In the absence of additional cholesterol, the soluble receptor inactivates within minutes. Maximal stabilization of the oxytocin receptor requires a continuous supply with cholesterol from a cholesterol-rich environment. A structure–activity analysis of various cholesterol analogues and their effect …
Unusual oxygen binding behavior of a 24-meric crustacean hemocyanin.
2009
Abstract Hemocyanins from Crustacea usually are found as 1 × 6 or 2 × 6-meric assemblies. An exception is the hemocyanin isolated from thalassinidean shrimps where the main component is a 24-meric structure. Our analysis of oxygen binding data of the thalassinidean shrimp Upogebia pusilla based on a three-state MWC-model revealed that despite the 24-meric structure the functional properties can be described very well based on the hexamer as allosteric unit. In contrast to the hemocyanins from other thalassinidean shrimps the oxygen affinity of hemocyanin from U. pusilla is increased upon addition of l -lactate. A particular feature of this hemocyanin seems to be that l -lactate already enha…
EFFICACY OF REPETITIVE TRANSCRANIAL MAGNETIC STIMULATION/TRANSCRANIAL DIRECT CURRENT STIMULATION IN COGNITIVE NEUROREHABILITATION
2008
Summary: Cognitive deficits are a common consequence of neurologic disease, in particular, of traumatic brain injury, stroke, and neurodegenerative disorders, and there is evidence that specific cognitive training may be effective in cognitive rehabilitation. Several investigations emphasize the fact that interacting with cortical activity, by means of cortical stimulation, can positively affect the short-term cognitive performance and improve the rehabilitation potential of neurologic patients. In this respect, preliminary evidence suggests that cortical stimulation may play a role in treating aphasia, unilateral neglect, and other cognitive disorders. Several possible mechanisms can accou…
Regulation of cytochrome P450 IID by acute phase mediators in C3H/HeJ mice.
1992
Abstract Cytochrome P450 IID6 is a drug metabolizing enzyme and the major target antigen in LKM-1 antibody positive chronic active hepatitis. The histological hallmark of chronic active hepatitis is a lymphocytic infiltrate in the liver. It is unknown whether and how cytokines produced and secreted by these tissue infiltrating mononuclear cells regulate the cellular expression of cytochrome P450 IID6. To study the effect of interleukin 1, tumor necrosis factor and interleukin 6 on the hepatocellular RNA expression of cytochrome P450 IID, we injected each of the cytokines in C3H HeJ mice. We found a time-dependent suppression of the cytochrome in the liver. Six hours after the intraperitonea…