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Autonomic System (autonomic + system)
Selected AbstractsWere volatile organic compounds the inducing factors for subjective symptoms of employees working in newly constructed hospitals?ENVIRONMENTAL TOXICOLOGY, Issue 4 2004Tomoko Takigawa Abstract This study demonstrated possible relationships between environmental, personal, and occupational factors and changes in the subjective health symptoms of 214 employees after the relocation of a hospital in a region of Japan. Eight indoor volatile organic compounds (VOCs) were detected in at least one of the 19 rooms investigated, and total VOC (TVOC) concentrations in 8 rooms exceeded the advisable value (400 ,g/m3) established by the Ministry of Health, Labour and Welfare of Japan. Formaldehyde was detected in all the investigated rooms, but none of the results exceeded the guideline value (100 ,g/m3). Multiple logistic regression analysis was applied to select variables significantly associated with the subjective symptoms that can be induced by sick building syndrome. The results showed that subjective symptoms of deterioration in the skin, eye, ear, throat, chest, central nervous system, autonomic system, musculoskeletal system, and digestive system among employees were associated mainly with gender difference and high TVOC concentrations (>1200 ,g/m3). Long work hours (>50 h per week) in females and smoking in males were to be blamed for the deterioration of their symptoms. The present findings suggest that to protect employees from indoor environment-related adverse health effects, it is necessary to reduce the concentration of indoor chemicals in new buildings, to decrease work hours, and to forbid smoking. © 2004 Wiley Periodicals, Inc. Environ Toxicol 19: 280,290, 2004. [source] Cardiac Dysrhythmia Associated with the Immediate Postictal State after Maximal Electroshock in Freely Moving RatEPILEPSIA, Issue 4 2002Olivier Darbin Summary: ,Purpose: Cardiac autonomic changes accompany complex partial seizures and generalized tonic,clonic seizures, and participate, at least partially, in the sudden and unexpected death in epilepsy (SUDEP). The analysis of the heart rate variability (HRV) is one of the simplest ways of providing insight into autonomic functions. The entropy quantifies the repetition of complex patterns in a signal and refers to systems randomness, regularity, and predictability. Clinical investigations have reported that entropy decreases in patients with a high risk of sudden cardiac death. The goal of this study was to evaluate the effects of the maximal electroshock (MES) on the entropy of HRV, monitored in the immediate postictal stage in the model of the freely moving rat. Methods: Entropy changes were correlated with the high and low frequencies of spectral analysis, which reflect the participation of the sympathetic and parasympathetic activities. Results: MES-induced arrhythmia is characterized by an HRV increase, an imbalance in favor of the parasympathetic activity, and a decrease in the entropy. Entropy decrease was restricted to the duration of the arrhythmia, suggesting that the postictal arrhythmia may be associated with a higher risk of lethal cardiac complications. Nevertheless, entropy changes did not correlate with spectral changes. Conclusions: The results suggest that the imbalance demonstrated in the spectral domain explains only partially the contribution of each autonomic system in the complexity of the heart rate during the postictal state. [source] New insights into the pathology of Parkinson's disease: does the peripheral autonomic system become central?EUROPEAN JOURNAL OF NEUROLOGY, Issue 2008A. Probst Recent studies in aged, neurologically unimpaired subjects have pointed to a specific induction site of the pathological process of Parkinson's disease (PD) in the region of the dorsal glossopharyngeus,vagus complex as well as in the anterior olfactory nucleus. From the lower brainstem, the disease process would then pursue an ascending course and involve more rostral brainstem areas, limbic structures, and eventually the cerebral cortex. One barrier to the acceptance of the caudal medullary structures as the induction site of PD pathology is that not all parts of the nervous system have been investigated for the presence of PD-associated lesions in cases of early asymptomatic PD. Using alpha-synuclein immunostaining, we investigated the brain, the sacral, and thoracic autonomic nuclei of the spinal cord as well as several components of the peripheral autonomic nervous system in a autopsy cohort of 98 neurologically unimpaired subjects aged 64 or more. Our data indicate that the autonomic nuclei of the spinal cord and the peripheral autonomic nervous system belong to the most constantly and earliest affected regions next to medullary structures and the olfactory nerves in neurologically unimpaired older individuals, thus providing a pathological basis for early premotor autonomic dysfunctions at a prodromal stage of PD. [source] Revisiting Autonomic Dysfunction in End-Stage Renal Disease PatientsHEMODIALYSIS INTERNATIONAL, Issue 3 2003Jocemir R. Lugon Background:,Autonomic dysfunction is frequent in end-stage renal disease (ESRD) patients, but both the relative involvement of the parasympathetic and sympathetic branches and the role of antihypertensive drugs in this setting are still controversial. The present study addressed these issues employing a battery of standard noninvasive cardiovascular autonomic tests. Methods:,Sympathetic (S) function was evaluated by responses of both systolic blood pressure (BP) to passive tilting and diastolic BP to handgrip; parasympathetic (P) function, through the respiratory sinus arrhythmia test and the heart rate response to the 4-s unloaded exercise test. Additional tests influenced by both branches of the autonomic system (P + S) were accomplished by the assessment of heart rate response to the Valsalva maneuver, handgrip, and tilting. Results:,Studied subjects belonged to one of the three groups: ESRD patients not requiring BP medications (n = 11; 8 men, 3 women); ESRD patients receiving antihypertensive therapy (n = 36; 21 men, 15 women); and apparently healthy controls (n = 15; 10 men, 5 women). When the variables grouped according to the branch of the autonomic nervous system predominantly probed were analyzed, only the frequency of impaired sympathetic autonomic responses was higher in ESRD patients not receiving BP drugs compared to controls (55 vs. 23%, P = 0.040). In contrast, when ESRD patients receiving BP drugs were compared to controls, the differences became significant in S, P, and P + S tests (46 vs. 23%, P = 0.045; 22 vs. 3%, P = 0.020; and 34 vs. 13%, P = 0.010, respectively). With the criterion of more than one positive finding in any of the variables examined for diagnosing autonomic dysfunction, the prevalence of autonomic dysfunction was 20% in controls, 64% in ESRD patients not receiving BP drugs (P = 0.005 vs. controls), and 67% in ESRD patients receiving BP drugs (P = 0.043 vs. controls). Conclusions:,ESRD continues to be associated with a high prevalence of autonomic dysfunction. ESRD patients receiving BP drugs were found to have detectable impairment in the entire autonomic system in contrast to those not receiving BP drugs in whom inadequate responses were restricted to the sympathetic branch. [source] Administration of noradrenaline in the autonomic ganglia modifies the testosterone release from the testis using an ex vivo systemINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 4 2009Zulema Y. Sosa Summary The male gonad receives nerve fibres from the autonomic ganglionic system. These fibres converge on the testis along two pathways, the superior and the inferior spermatic nerves. The superior spermatic nerve runs from the superior mesenteric ganglion alongside the testicular artery, whereas the inferior spermatic nerve originates in inferior mesenteric ganglion, accompanies the vas deferens and penetrates the inferior pole of the testis. The aim of this work was to evaluate androgen release after the addition of noradrenaline or adrenoreceptor antagonists (propranolol or phentolamine) to the ganglionic compartment. An ex vivo system used in a previous work was incubated in two separate containers, one for the testis and the other for the ganglion. Both organs remain interconnected (as in vivo) by the respective spermatic nerve. When noradrenaline was added to the inferior mesenteric ganglion, testosterone release in the gonad container underwent a progressive and significant increment. Propranolol diminishes and phentolamine increases the androgen release. When using the superior mesenteric ganglion, no changes were observed. These results indicate that the ganglionic stimulation of the autonomic system clearly participates in testosterone release from the testis. This effect depends on the ganglion involved. These results make it evident that not only the classical and well-known hypothalamus,hypophysial axis, but also the peripheral nervous system, via the autonomic ganglia, are directly involved in the endocrine control of the testis. [source] Evolution of the amygdaloid complex in vertebrates, with special reference to the anamnio-amniotic transitionJOURNAL OF ANATOMY, Issue 2 2007Nerea Moreno Abstract Numerous studies over the last few years have demonstrated that the amygdaloid complex in amniotes shares basic developmental, hodological and neurochemical features. Furthermore, homologous territories of all the main amygdaloid subdivisions have been recognized among amniotes, primarily highlighted by the common expression patterns for numerous developmental genes. Thus, derivatives from the lateral pallium, ventral pallium and subpallium constitute the fundamental parts of the amygdaloid complex. With the development of new technical approaches, study of the precise neuroanatomy of the telencephalon of the anuran amphibians (anamniotes) has been possible. Current embryological, hodological and immunohistochemical evidence strongly suggests that most of the structures present in amniotes are recognizable in these anamniotes. These investigations have yielded enough results to support the notion that the organization of the anuran amygdaloid complex includes subdivisions with their origin in ventral pallial and subpallial territories; a strong relationship with the vomeronasal and olfactory systems; abundant intra-amygdaloid connections; a main output centre involved in the autonomic system; recognizable amygdaloid fibre systems; and distinct chemoarchitecture. Therefore, the new ideas regarding the amygdaloid evolution based on the recent findings in anamniotes, and especially in anurans, strongly support the notion that basic amygdaloid structures were present at least in the brain of ancestral tetrapods organized following a basic plan shared by tetrapods. [source] Baroreceptor sensitivity and baroreceptor effectiveness index in cirrhosis: the relevance of hepatic venous pressure gradientLIVER INTERNATIONAL, Issue 2 2010Simonetta Genovesi Abstract Background: Autonomic dysfunction has been reported as one of the complications of cirrhosis. Aims: The aim of this study was to test autonomic dysfunction in cirrhotic patients by analysing the baroreflex sensitivity and the baroreceptor effectiveness index (BEI), in order to determine its correlation with the severity and the aetiology of liver disease. Moreover, we explored the relationship between baroreceptor function and mortality in our cohort of patients. Methods: Clinical and laboratory evaluation, hepatic venous pressure gradient (HVPG) and haemodynamic setting and baroreceptor function were assessed in 45 cirrhotic patients (median age 55, range 38,72 years) divided in groups according to the severity of their disease (26 patients Child A, 13 patients Child B and six patients Child C). Results: Baroreceptor sensitivity and BEI were impaired in more advanced cirrhotic patients compared with subjects with milder disease (P<0.001). HVPG was significantly, independently and inversely correlated with baroreceptor sensitivity (P=0.003). More severe impairment of baroreceptor function was associated with a higher mortality (P=0.04) and subjects with alcohol-related cirrhosis presented worse baroreceptor function (P=0.032) and poorer survival (P=0.003) compared with subjects with post-viral liver disease. Conclusions: These data support the hypothesis that liver disease severity and particularly portal hypertension have an important role in the derangement of baroreceptor function. The aetiology of cirrhosis seems to be related to baroreceptor impairment as well. Mortality rate is higher in subjects with a more damaged autonomic system, strengthening the idea of a worse prognosis in cirrhotic patients with autonomic neuropathy. [source] Derangement of Heart Rate Variability During a Catastrophic Earthquake: A Possible Mechanism for Increased Heart AttacksPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 11 2001LIAN-YU LIN LIN, L.-Y., et al.: Derangement of Heart Rate Variability During a Catastrophic Earthquake: A Possible Mechanism for Increased Heart Attacks. At 1:47 AM on September 21, 1999, the middle part of Taiwan was struck by a major earthquake measuring 7.3 on the Richter scale. It has been shown that the mental stress caused by an earthquake could lead to a short- or long-term increase in frequency of cardiac death probably through activation of the sympathetic nervous system. The aim of this study was to investigate the effects of emotional stress on the autonomic system during an actual earthquake. Fifteen patients receiving a 24-hour Holter ECG study starting from 10 ± 4 hours before the onset of the earthquake were included for the analysis of time- and frequency-domains of heart rate variability (HRV) at several time periods. A 24-hour Holter study recorded 2,6 months before the earthquake in 30 age- and sex-matched subjects served as the control group. Heart rate and the low frequency (LF) to high frequency (HF) ratio increased significantly after the earthquake and were attributed mainly to the withdrawal of the high frequency component (parasympathetic activity) of HRV. Sympathetic activation was blunted in elderly subjects > 60 years old. The concomitant ST-T depression observed in the Holter study correlated with a higher increment of LF as compared to HF components. The changes observed in HRV recovered completely 40 minutes following the earthquake. The derangement of HRV results from the withdrawal of the parasympathetic component and the arousal of sympathetic activity by the stressful earthquake. However, this autonomic derangement returned towards normal 40 minutes following the earthquake. [source] Immunology of disorders of neuromuscular transmissionACTA NEUROLOGICA SCANDINAVICA, Issue 2006A. Vincent The neuromuscular junction (NMJ) is a prototype synapse and myasthenia gravis is the prototypic antibody-mediated disorder. There are now three other disorders of neuromuscular transmission caused by antibodies to other essential components of the NMJ. Antibodies to the muscle-specific kinase, MuSK, are defining a new form of myasthenia that can be associated with muscle atrophy. Antibodies to voltage-gated calcium channels are responsible for muscle weakness and autonomic dysfunction in the Lambert Eaton myasthenic syndrome. Antibodies to voltage-gated potassium channels are found in patients with a range of disorders affecting the NMJ, the autonomic system or the central nervous system. The pathogenic mechanisms probably depend on the IgG subclass of the antibodies and are only partly shared between the diseases. [source] | ||||||||||