scholarly journals Salivary Melatonin Concentrations in a Sitting and a Standing Position

2013 ◽  
Vol 2013 ◽  
pp. 1-4 ◽  
Author(s):  
Tomoaki Kozaki ◽  
Toshihiko Arata ◽  
Ayaka Kubokawa
Keyword(s):  
Light Condition ◽  
Standing Position ◽  
Sitting Position ◽  
Melatonin Secretion ◽  
Salivary Melatonin ◽  
Dim Light ◽  
Age Range

This study aimed to examine differences in salivary melatonin concentrations between the sitting and standing positions. Ten subjects (age range: 20–22 years; 5 males and 5 females) participated in the study and provided written consent. In the sitting condition, the subjects sat on a chair from 23:30 h to 1:00 h, whereas in the standing condition, the subjects sat on a chair from 23:30 h to 0:30 h and stood on the floor from 0:30 h to 1:00 h. Saliva samples were obtained at 0:25 h and 1:00 h from all subjects. The experiment was performed under a dim light condition (<10 lx). No significant differences were observed in melatonin concentrations between the two positions at 0:25 h; however, melatonin concentrations in the standing condition were significantly greater than those in the sitting condition at 1:00 h. These results show that melatonin secretion is significantly greater in the standing position than that in the sitting position.

scholarly journals Circadian Profile of Salivary Melatonin Secretion in Hypoxic Ischemic Encephalopathy

2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Łukasz Kapek ◽  
Justyna Paprocka ◽  
Marek Kijonka ◽  
Maria Zych ◽  
Ewa Emich-Widera ◽  
...  
Keyword(s):  
Least Squares Method ◽  
Nonlinear Least Squares ◽  
Linear Interpolation ◽  
Hypoxic Ischemic Encephalopathy ◽  
Melatonin Secretion ◽  
Threshold Method ◽  
Salivary Melatonin ◽  
Dim Light ◽  
Nonlinear Least Squares Method ◽  
Ischemic Encephalopathy

Purpose. In the present study, the salivary melatonin secretion in the hypoxic ischemic encephalopathy (HIE) children was measured. The logit model was fitted to the data to obtain the salivary dim light melatonin onsets (DLMOs), and the results were compared with the values estimated from the classic threshold method with a linear interpolation and those previously published for the blood measurements. Materials and Methods. 9 patients suffering from HIE aged from 65 to 80 months were included in the study. The melatonin levels were assessed by a radioimmunoassay (RIA). The diurnal melatonin secretion was estimated using a nonlinear least squares method. Student’s t-test and the Mann–Whitney U test were used for the comparisons of the obtained parameters. Results. The circadian profiles of the melatonin secretion for both calculation methods do not differ statistically. The DLMO parameters obtained in the blood and saliva samples in children with hypoxic ischemic encephalopathy were similar.

scholarly journals Intraocular pressure and choroidal thickness postural changes in multiple system atrophy and Parkinson’s disease

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Maddalena De Bernardo ◽  
Giulio Salerno ◽  
Marco Gioia ◽  
Luigi Capasso ◽  
Maria Claudia Russillo ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Intraocular Pressure ◽  
Multiple System Atrophy ◽  
Choroidal Thickness ◽  
Corneal Thickness ◽  
Standing Position ◽  
Sitting Position ◽  
Postural Changes ◽  
Iop Measurement

AbstractTo evaluate intraocular pressure (IOP) and choroidal thickness (ChT) postural changes in multiple system atrophy (MSA), Parkinson’s disease (PD) patients and healthy controls (HC). 20 MSA patients, 21 PD patients and 14 HC, were examined. All subjects underwent a complete examination, including corneal thickness, ChT, IOP and axial length (AL) measurements. IOP measurement was performed in supine, sitting, and standing positions, whereas ChT in sitting and standing positions. Supine to standing IOP variations were significantly higher in MSA vs PD(p = 0.01) and in MSA vs HC (p < 0.0001), whereas no significant differences were observed between PD and HC (p = 0.397). Mean sub-foveal ChT in MSA was 240 ± 92 μm in sitting position, and 215 ± 94 μm in standing position with a significant reduction (p = 0.008). Mean sub-foveal ChT in PD was 258 ± 79 μm in sitting position, and 259 ± 76 μm in standing position (p = 0.887). In HC it was 244 ± 36 μm in sitting position, and 256 ± 37 μm in standing position with a significant increase (p = 0.007). The significant IOP and ChT postural changes can be considered additional hallmarks of autonomic dysfunction in MSA and further studies are needed to consider them as biomarkers in the differential diagnosis with PD.

The semantics of German posture and placement verbs in noun-verb phrases

2019 ◽  
Vol 7 (1) ◽  
pp. 93-114
Author(s):  
Manon Hermann
Keyword(s):  
Standing Position ◽  
Sitting Position ◽  
Image Schemas ◽  
Verb Phrases ◽  
Preliminary Study

Abstract In this contribution, we study the use of the German verbs stehen (‘to stand’), sitzen (‘to sit’) and their causative equivalents stellen (‘to put in a standing position’) and setzen (‘to put in a sitting position’) in noun-verb phrases, such as an der Spitze stehen (lit. ‘to stand at the top’ = ‘to be at the top’) or auf die Beine stellen (lit. ‘to put upright on the legs’ = ‘to achieve’). Among these phrases we are looking more particularly at the subcategory of complex noun-verb phrases which are commonly referred to as Funktionsverbgefüge in German. Numerous examples from the corpus DeReKo (IDS) are analyzed with the aim of identifying the conceptualizations and image schemas that motivate their use. This preliminary study shows that, even if these verbs seem very close at first sight, their use is highly differentiated.

If You’re Happy and You Know it Stay Alert: The Effects of Lighting on Vigilance Performance and Affective State

2021 ◽  
Vol 65 (1) ◽  
pp. 854-858
Author(s):  
Lauren E. Monroe ◽  
Samantha L. Smith
Keyword(s):  
Affective State ◽  
Light Condition ◽  
Bright Light ◽  
Extended Period ◽  
Light Therapy ◽  
Speed Of Information Processing ◽  
Attention Tasks ◽  
High Workload ◽  
Dim Light ◽  
Over Time

Vigilance, or sustained attention tasks involve detecting critical signals, embedded amid more frequent neutral signals, over an extended period of time. A decline in performance, engagement, and arousal over time, as well as high workload and stress, are common outcomes of such tasks. Exposure to broad-spectrum or short wavelength bright light has been found to positively impact alertness, speed of information processing, and mood, but has not been extensively explored in the vigilance domain. The present study explored whether a light therapy lamp could mitigate the negative vigilance outcomes found in both performance and affective state. Results indicated that the therapy light did not prevent a decline in detection of critical signals over time, nor significantly impact workload, sleepiness, or subjective stress state compared to a dim light condition. However, mood questionnaire results suggest that lighting may impact separate constructs of arousal and tiredness, warranting further research.

scholarly journals Melatonin Secretion and Increased Daytime Sleepiness in Childhood Craniopharyngioma Patients

2002 ◽  
Vol 87 (8) ◽  
pp. 3993-3996 ◽  
Author(s):  
Hermann L. Müller ◽  
Georg Handwerker ◽  
Brigitte Wollny ◽  
Andreas Faldum ◽  
Niels Sörensen
Keyword(s):  
Daytime Sleepiness ◽  
Epworth Sleepiness Scale ◽  
Sleep Disturbances ◽  
Tumor Diagnosis ◽  
Melatonin Secretion ◽  
Tumor Patients ◽  
F Test ◽  
Hypothalamic Lesions ◽  
Severely Obese ◽  
Salivary Melatonin

Craniopharyngioma is a rare dysontogenetic benign tumor. Patients frequently suffer from endocrine deficiencies, sleep disturbances, and obesity due to pituitary and hypothalamic lesions. A self-assessment daytime sleepiness questionnaire (German version of the Epworth Sleepiness Scale) was used to evaluate 79 patients with childhood craniopharyngioma. Because hypothalamic lesions may explain daytime sleepiness in craniopharyngioma patients, salivary melatonin and cortisol concentrations were examined in obese and nonobese craniopharyngioma patients (n = 79), patients with hypothalamic pilocytic astrocytoma (n = 19), and control subjects (n = 30). Using a general linear model procedure analyzing the influence of body mass index (BMI) and tumor diagnosis on diurnal salivary melatonin, we found that morning salivary melatonin levels were related to BMI (by F test, P = 0.004) and tumor diagnosis (by F test, P = 0.032). Also for nighttime salivary melatonin levels significant relations with BMI (by F test, P &lt; 0.001) and tumor diagnosis (by F test, P = 0.025) were detectable. Melatonin concentrations in saliva of craniopharyngioma patients collected at night or in the morning showed a negative correlation (night: Spearman’s ρ = −0.42; P = 0.001; morning: Spearman’s ρ = −0.31; P = 0.020) with the patient’s Epworth Sleepiness Scale score. Severely obese craniopharyngioma patients and severely obese hypothalamic tumor patients had similar patterns of melatonin secretion. Differences in terms of diurnal salivary cortisol concentrations were not detectable when patient groups and controls were compared. We speculate that hypothalamic lesions might be responsible for both obesity and daytime sleepiness. As decreased nocturnal melatonin levels were associated with increased daytime sleepiness, BMI, and hypothalamic tumor diagnosis, further studies on the beneficial effects of melatonin substitution on daytime sleepiness and weight control in these patients are warranted.

scholarly journals Easy-Riding Compact Electric Shopping Vehicle

2021 ◽  
Vol 33 (5) ◽  
pp. 1178-1189
Author(s):  
Takeharu Hayashi ◽  
Yoshihiko Takahashi ◽  
Satoru Yamaguchi ◽  
◽  
Keyword(s):  
Electric Power ◽  
Electric Vehicle ◽  
Pulse Width ◽  
Pulse Width Modulation ◽  
Standing Position ◽  
Power Source ◽  
Sitting Position ◽  
Speed Controller ◽  
Experimental Vehicle ◽  
Modulation Control

We are developing a small compact electric vehicle for shopping purposes. In this study, we fabricated an experimental vehicle, that uses only six small rechargeable AA batteries (7.2 V, approximately 2 A·h) as an electric power source. The vehicle user can select between two driving positions: standing and sitting. A compact transmission with a 90-W DC motor and a speed controller that uses pulse width modulation control was designed as an actuating system. Running experiments were conducted to observe the performance of the fabricated vehicle on a flat floor in a gymnasium. The fabricated vehicle was able to operate for 52 min at a speed of 2.73 km/h. The getting-on and getting-off processes in the vehicle were repeated many times during shopping. The human leg strain while getting on and off the vehicle was investigated by electromyogram measurement. During the getting-on and getting-off processes in the vehicle, the myoelectric potential of the quadriceps increased in the sitting position but did not increase in the standing position. The experimental results show that a user suffers more strain in the sitting position than in the standing position.

scholarly journals COLORECTAL CARCINOMA;

2013 ◽  
Vol 20 (03) ◽  
pp. 472-477
Author(s):  
MOHAMMAD ADNAN NAZEER ◽  
QAMAR SHAHZAD ◽  
HARUN MAJID DAR ◽  
Asma Samreen ◽  
Humaira Aalam
Keyword(s):  
Colorectal Carcinoma ◽  
Bowel Obstruction ◽  
Large Bowel ◽  
Standing Position ◽  
Large Bowel Obstruction ◽  
Sigmoid Volvulus ◽  
Colorectal Cancers ◽  
Fluid Interfaces ◽  
Biochemical Tests ◽  
Age Range

Introduction: Large bowel obstruction due to colorectal carcinoma occurs in up to 20% of the patients and usually2-4 accompanied by morbidity and mortality . Almost 25 % deaths occur post-operatively following surgery for colorectal cancers occur in1 those who initially present with obstruction . Usually elderly patients with associated co-morbidities presents with bowel obstruction.Objective: Find out the frequency of colorectal cancers in patients presenting with large bowel obstruction. Design: Prospective crosssectional study. Setting: Shaikh Zayed Hospital Lahore. Period: from 31st December 2010 to 31st December 2012. Materials &Methods: A total 20 patients were presented with large bowel obstruction with the age ranges between 40 to 70 years. All the 20 patientsunderwent routine haematological and biochemical tests. In these patients an abdominal x-ray in a supine or standing position was takenand dilated loops of bowel, air-fluid interfaces, or both was observed then Contrast radiography(Barium/gastrograffin) was done todefine the site and extent of the obstruction. An abdominal computed tomography scan was done to evaluate the extent of the disease.Colonoscopy was also carried out in the patients with colorectal cancers to find out the size and location of the tumor and biopsy taken bycolonoscope. Results: 12 patients out of 20 presented with large bowel obstruction were diagnosed to have a colorectal cancers and theage ranges from 60 to 70 years. The 8 patients were diagnosed to have a sigmoid colonic tumour and 4 patients were suffering from atumour of recto sigmoid junction. Whereas in rest of the 8 patients the large bowel obstruction was due to other benign causes likevolvulus and intussusception and age range was 50 – 60 years. 6 patients were suffering from sigmoid volvulus and remaining 2 hadcolo-colic intussusception. Conclusions: It is concluded that the major cause of the large bowel obstruction is the left sided colorectalcancers the tumours of recto sigmoid junction.

Orthostatic intolerance: orthostatic hypotension and postural orthostatic tachycardia syndrome

ESC CardioMed ◽  
2018 ◽  
pp. 2032-2037
Author(s):  
Artur Fedorowski
Keyword(s):  
Orthostatic Hypotension ◽  
Orthostatic Intolerance ◽  
Wide Spectrum ◽  
Standing Position ◽  
Diagnostic Methods ◽  
Postural Orthostatic Tachycardia Syndrome ◽  
Unexplained Syncope ◽  
Clinical Variants ◽  
Age Range ◽  
Specific Symptoms

The impairment of adaptive mechanisms during orthostatic challenge may evoke orthostatic intolerance, a heterogeneous condition, in which the standing position elicits a fall in blood pressure and/or excessive tachycardia, accompanied by a wide spectrum of subjective symptoms such as dizziness, discomfort, nausea, and palpitations. Apart from chronic and potentially debilitating symptoms, orthostatic intolerance may occasionally lead to sudden loss of consciousness and fall injuries. Consequently, orthostatic intolerance should be considered as a possible cause of unexplained syncope. Two main forms of orthostatic intolerance are orthostatic hypotension (OH) and postural orthostatic tachycardia syndrome (POTS). Clinical variants of OH include initial, classical, and delayed forms. The prevalence of OH increases with age, ranging from less than 5% under 40 years to about 20% above 70 years of age, and is higher in chronic diseases, such as hypertension and diabetes, reaching above 35% in Parkinson’s disease and advanced kidney failure. The presence of OH is associated with a higher mortality and an increased incidence of cardiovascular disease, with the majority of patients being asymptomatic in normal conditions. In contrast, POTS affects predominantly young women (70–80%) within an age range of 15–40 years and is usually accompanied by non-specific symptoms: deconditioning, headache, cognitive impairment, and gastrointestinal dysfunction. Management of orthostatic intolerance includes both non-pharmacological and pharmacological methods with limited efficacy in the severe cases. Empirical treatment with vasoactive and volume expanding drugs for OH and POTS, and rhythm controlling therapy for POTS are recommended. Future studies on syndromes of orthostatic intolerance should focus on mechanisms leading to OH and POTS, novel diagnostic methods, and more effective therapeutic options.

Orthostatic intolerance: orthostatic hypotension and postural orthostatic tachycardia syndrome

ESC CardioMed ◽  
2018 ◽  
pp. 2032-2037
Author(s):  
Artur Fedorowski
Keyword(s):  
Orthostatic Hypotension ◽  
Orthostatic Intolerance ◽  
Wide Spectrum ◽  
Standing Position ◽  
Diagnostic Methods ◽  
Postural Orthostatic Tachycardia Syndrome ◽  
Unexplained Syncope ◽  
Clinical Variants ◽  
Age Range ◽  
Specific Symptoms

The impairment of adaptive mechanisms during orthostatic challenge may evoke orthostatic intolerance, a heterogeneous condition, in which the standing position elicits a fall in blood pressure and/or excessive tachycardia, accompanied by a wide spectrum of subjective symptoms such as dizziness, discomfort, nausea, and palpitations. Apart from chronic and potentially debilitating symptoms, orthostatic intolerance may occasionally lead to sudden loss of consciousness and fall injuries. Consequently, orthostatic intolerance should be considered as a possible cause of unexplained syncope. Two main forms of orthostatic intolerance are orthostatic hypotension (OH) and postural orthostatic tachycardia syndrome (POTS). Clinical variants of OH include initial, classical, and delayed forms. The prevalence of OH increases with age, ranging from less than 5% under 40 years to about 20% above 70 years of age, and is higher in chronic diseases, such as hypertension and diabetes, reaching above 35% in Parkinson’s disease and advanced kidney failure. The presence of OH is associated with a higher mortality and an increased incidence of cardiovascular disease, with the majority of patients being asymptomatic in normal conditions. In contrast, POTS affects predominantly young women (70–80%) within an age range of 15–40 years and is usually accompanied by non-specific symptoms: deconditioning, headache, cognitive impairment, and gastrointestinal dysfunction. Management of orthostatic intolerance includes both non-pharmacological and pharmacological methods with limited efficacy in the severe cases. Empirical treatment with vasoactive and volume expanding drugs for OH and POTS, and rhythm controlling therapy for POTS are recommended. Future studies on syndromes of orthostatic intolerance should focus on mechanisms leading to OH and POTS, novel diagnostic methods, and more effective therapeutic options.

scholarly journals Blunted Nocturnal Salivary Melatonin Secretion Profiles in Military-Related Posttraumatic Stress Disorder

2019 ◽  
Vol 10 ◽  
Author(s):  
Michel A. Paul ◽  
Ryan J. Love ◽  
Rakesh Jetly ◽  
J. Donald Richardson ◽  
Ruth A. Lanius ◽  
...  
Keyword(s):  
Posttraumatic Stress Disorder ◽  
Posttraumatic Stress ◽  
Stress Disorder ◽  
Melatonin Secretion ◽  
Salivary Melatonin
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