Effect of relaxation on the level of nursing internship students' stress

Objective: To explore how relaxation reduce the effect of stress in Iranian nursing students.Methods: A total of 40 nursing students were randomly selected and divided into two groups of test and control each with 20 students.An exam questionnaire consisting of the stress test of Spilberger and control of physiological determinants(blood pressure,pulse respiration,temperature) was performed to two groups.The practice of relaxation continued for two weeks and three times a day.Data were collected and analysed using t-test and Chi-square.Results: Two groups did not show any difference in relation to the average of physiological determinants before and after investigation.However,pulse was significantly different between the two groups.The average scores of stress before and after relaxation were significantly differed between the two groups investigation so that the level of stress was reduced in the test group(t= 2.5,df =39,P= 0.02).Conclusion: To alleviate stressors associated with clinical practice and create a healthy work environment for practice it is recommended that nursing students have some relaxation before entering practical environments.     

Counter-stress effects of relaxation on proinflammatory and anti-inflammatory cytokines

The counter-stress effects of relaxation on proinflammatory and anti-inflammatory cytokines were examined. From 36 medical students, 18 were randomly assigned to the relaxation group, and 18 were randomly assigned to the non-relaxation group. Relaxation lasted for four weeks. The levels of stimulated production of IL-6, TNF-α, and IL-10, and blood pressure were measured during the non-examination period (baseline period) and the pre-examination period (stress period). The levels of perceived stress were assessed by the Global Assessment of Recent Stress (GARS) scale, the Stress Response Inventory (SRI) and the Symptom Checklist-90-Revised (SCL-90-R) anxiety subscale. Repeat measure ANOVA revealed that the SRI total score, scores of the SCL-90-R anxiety subscale and diastolic blood pressure were significantly higher during the stress period than during the baseline period regardless of groups. The level of IL-6 production was significantly lower but the level of IL-10 production was significantly higher during the stress period than during the baseline period. Significant reduction in the delta (stress period value minus baseline period value) in the total GARS score, systolic and diastolic blood pressure, the levels of IL-6 and TNF-α production but significant enhancement in the delta in the level of the IL-10 production were found in the relaxation group compared with the non-relaxation group. These results suggest that relaxation is associated with reduction in stress-induced psychological or physiological responses and proinflammatory cytokine alterations but with enhancement in stress-induced anti-inflammatory cytokine alteration. Therefore, relaxation is more likely to have counter-stress effect on proinflammatory cytokines than on anti-inflammatory cytokine.     

Pharmacologic responses of the mouse urinary bladder

The aim of the study was to determine pathways involved in contraction and relaxation of the mouse urinary bladder. Mouse bladder strips were set up in gassed Krebs-bicarbonate solution and responses to various drugs and electrical field stimulation were obtained. Isoprenaline (b-receptor agonist) caused a 63% inhibition of carbachol precontracted detrusor (EC50=2nM). Carbachol caused contraction (EC50=0.3μM), responses were antagonised more potently by 4-DAMP (M3-antagonist) than methoctramine (M2-antagonist). Electrical field stimulation caused contraction, which was inhibited by atropine (60%) and less by guanethidine and α,β-methylene-ATP. The neurogenic responses were not potentiated by inhibition of nitric oxide synthase. Presence of an intact urothelium significantly depressed responses to carbachol (p=0.02) and addition of indomethacin and L-NNA to remove prostaglandin and nitric oxide production respectively did not prevent the inhibitory effect of the urothelium. In conclusion, b-receptor agonists cause relaxation and muscarinic agonists cause contraction via the M3-receptor. Acetylcholine is the main neurotransmitter causing contraction while nitric oxide has a minor role. The mouse and human urothelium are similar in releasing a factor that inhibits contraction of the detrusor muscle which is unidentified but is not nitric oxide or a prostaglandin. Therefore, the mouse may be used as a model to study the lower urinary tract.     

麻黄新型仿生提取方法研究

目的：探索麻黄的新型仿生提取方法。方法：采用液．液连续萃取法,用酸水或碱水模拟胃或肠环境,以正辛醇模拟生物膜结构,形成萃取体系提取麻黄。并对该提取技术与酸水煮提法进行麻黄碱和离体豚鼠气管的舒张率比较。结果：本仿生提取方法与酸水煮提法相比：麻黄总碱提取率提高15％以上、对豚鼠离体气管舒张率提高1．2倍以上,而浸膏得率降低约1倍。结论：该仿生提取方法提取麻黄可行。     

Contrast enhanced cartilage imaging: Comparison of ionic and non-ionic contrast agents

Our objective was to compare relaxation effects, dynamics and spatial distributions of ionic and non-ionic contrast agents in articular cartilage at concentrations typically used for direct MR arthrography at 1.5T. Dynamic MR-studies over 11h were performed in 15 bovine patella specimens. For each of the contrast agents gadopentetate dimeglumine, gadobenate dimeglumine, gadoteridol and mangafodipir trinatrium three patellae were placed in 2.5mmol/L contrast solution. Simultaneous measurements of T(1) and T(2) were performed every 30min using a high-spatial-resolution "MIX"-sequence. T(1), T(2) and DeltaR(1), DeltaR(2) profile plots across cartilage thickness were calculated to demonstrate the spatial and temporal distributions. The charge is one of the main factors which controls the amount of the contrast media diffusing into intact cartilage, but independent of the charge, the spatial distribution across cartilage thickness remains highly inhomogeneous even after 11h of diffusion. The absolute DeltaR(2)-effect in cartilage is at least as large as the DeltaR(1)-effect for all contrast agents. Maximum changes were 5-12s(-1) for DeltaR(1) and 8-15s(-1) for DeltaR(2). This study indicates that for morphologically intact cartilage only the amount of contrast agents within cartilage is determined by the charge but not the spatial distribution across cartilage thickness. In addition, DeltaR(2) can be considered for quantification of contrast agent concentrations, since it is of the same magnitude and less time consuming to measure than DeltaR(1).     

The effect of Benson Relaxation Technique on rheumatoid arthritis patients: extended report

Rheumatoid arthritis (RA) is a chronic disease and has the highest rate of prevalence among rheumatic inflammatory diseases. The purpose of this study was to determine the effect of Benson Relaxation Technique (BRT) combined with medication on disease activity in patients with RA. Following ethical approval, 50 consecutive matched patients were selected and allocated into two groups, either an experimental or a control group. Patients in the experimental group received BRT combined with medication and patients in the control group were given only medication. Clinical symptoms, laboratory findings, anxiety, depression and feeling of well-being were measured before and after intervention to evaluate the effect of BRT. There was a significant difference between the two groups in anxiety, depression and feeling of well-being. Changes in clinical symptoms and laboratory findings were not large enough to be statistically significant between the two groups, but they indicated decline in disease progress. The results demonstrate that BRT can be an effective technique in reducing disease process in patients suffering from RA. However, in order to support the findings of this trial, studies with large sample size and > 8-week intervention are recommended.     

Relaxierung und elektromyographische Identifikation des N. laryngeus recurrens

Introduction. Electromyography for the identification of the recurrent laryngeal nerve is gaining ever more acceptance in thyroid surgery. Relaxation of the patient, e.g., to improve intubation conditions for anesthesia, carries a potential risk for error. Method. After definite identification of the recurrent laryngeal nerve and the vagus nerve (Neurosign 100, Magstim Co., Wales), ten consecutive patients were relaxed with mivacurium and atracurium besylate at a weight-dependent ED95 dosage. After peripheral relaxation was achieved (TOF-Watch, Organon Teknika Corp., at the adductor muscle of the thumb), the signal derived via the vocal muscle was assessed acoustically in 3-min intervals by the surgeon and graphically recorded by computer (EWACS, Inomed Co.). Results. Complete peripheral relaxation was attained with mivacurium after 3–7 min and with atracurium after 7–11 min. A decrease in amplitude of the vocal muscle signal of >60% was recognized by the surgeon as a weakened signal and could be confirmed during an average duration of 13.3 min with mivacurium (maximum: 37 min) and 17.7 min with atracurium besylate (maximum: 23 min), respectively. Complete obliteration of the acoustic signal (<20% of the initial signal) occurred in three of six patients treated with mivacurium and in four of four patients treated with atracurium. Conclusions. The accuracy of electromyography of the recurrent laryngeal nerve can be substantially impaired by the administration of relaxants. If this medication cannot be dispensed with, the surgeon must be aware of the situation. In these cases, a peripheral relaxometer should also be employed to monitor relaxation as it subsides.     

Relaxant and contractile responses of porcine pulmonary arteries to a thrombin receptor activating peptide (TRAP)

Recent studies on cloning of the thrombin receptor, which belongs to the family of G-protein-coupled receptors, suggest that thrombin cleaves a peptide from the extracellular N-terminus. A synthetic peptide of 14 amino acids corresponding to the sequence of the newly generated N-terminus was found to possess thrombin-like activity in several cells endowed with thrombin receptors. The relaxant and contractile effects of this thrombin receptor activating peptide (TRAP, Ser-Phe-Leu-Leu-ArgAsn-Pro-Asn-Asp-Lys Tyr-Glu-Pro-Phe) were investigated in porcine pulmonary arteries and compared with the action of thrombin.In PGF₂-precontracted vessels with intact endothelium, TRAP (0.3 – 10 mol/l) caused reversible transient and concentration-dependent relaxation which was absend after mechanical removal of the endothelium. Preincubation of the vessels with N^G-nitro-l-rarginine (200 mol/l) markedly reduced the relaxation. The TRAP-induced relaxation was associated with an increase in cGMP in the arteries. In comparison to thrombin, TRAP (EC₅₀: 0.8 mol/l) was less potent by more than three orders of magnitude.In endothelium-denuded pulmonary arteries TRAP (1–20 mol/l) caused a concentration-dependent contraction which was reversible after washout. The TRAP-induced contractile response was preceded by an increase in generation of inositol 1,4,5-triphosphate (IP₃); the peak of IP₃ accumulation was reached after 30 s. Compared with the contractile effect of thrombin, that of TRAP was weaker by three of magnitude.The vascular effect of TRAP was not inhibited by the thrombin inhibitors hirudin or heparin while the protein kinase C inhibitor staurosporine (0.1 mol/l) preferentially inhibited the tonic phase of contraction.The present findings suggest that TRAP mimics the dualistic vascular effects of thrombin caused by direct activation of thrombin receptors at endothelial and smooth muscle cells. Correspondence to: E. Glusa at the above address     

Effect of strength training on the relationship between magnetic resonance relaxation time and muscle fibre composition

Summary The effect of muscle hypertrophy on the relationship between magnetic resonance (MR) relaxation time and muscle fibre composition was investigated. Relaxation time and muscle fibre composition were measured in five subjects before and after a 20-week period of strength training. Muscle fibre composition in all subjects exhibited a significant shift to a predominance of fast-twitch (FT) fibres as a result of 20-week strength training (% area FT fibres: mean values from 49.8%, SD 17.9% to 57%, SD 5.6%; P<0.05). Longitudinal relaxation time (T₁) and transverse relaxation time (T₂) were prolonged significantly after strength training (T₁ mean values from 334.9 ms, SD 13.6 to 359.0 ms, SD 9.0, P<0.001; T₂ from 27.5 ms, SD 0.9 to 30.8 ms, SD 2.3, P<0.05). A constant relationship was observed in changes caused by strength training in muscle fibre composition (% area FT) and relaxation time, with a high correlation obtained between both parameters. These results indicate that MR relaxation time can be used for non-invasive estimation of muscle fibre composition.