Local temperature-sensitive mechanisms are important mediators of limb tissue hyperemia in the heat-stressed human at rest and during small muscle mass exercise.

Limb tissue and systemic blood flow increases with heat stress, but the underlying mechanisms remain poorly understood. Here, we tested the hypothesis that heat stress-induced increases in limb tissue perfusion are primarily mediated by local temperature-sensitive mechanisms. Leg and systemic temperatures and hemodynamics were measured at rest and during incremental single-legged knee extensor exercise in 15 males exposed to 1 h of either systemic passive heat-stress with simultaneous cooling of a single leg (n=8) or isolated leg heating or cooling (n=7). Systemic heat-stress increased core, skin and heated leg blood (Tb) temperatures, cardiac output and heated leg blood flow (LBF, 0.6 ± 0.1 l.min(-1); P0.05). Increased heated leg deep tissue BF was closely related to Tb (R(2) = 0.50; P0.05), despite unchanged systemic temperatures and hemodynamics. During incremental exercise, heated LBF was consistently maintained ~ 0.6 l.min(-1) higher than that in the cooled leg (P<0.01), with LBF and vascular conductance in both legs showing a strong correlation with their respective local Tb (R(2) = 0.85 and 0.95, P<0.05). We conclude that local temperature-sensitive mechanisms are important mediators in limb tissue perfusion regulation both at rest and during small-muscle mass exercise in hyperthermic humans.The invasive study was partially funded by Gatorade Sports Science Institute, PepsiCo

Progressive ataxia with oculo-palatal tremor and optic atrophy

The final publication is available at Springer via doi: 10.​1007/​s00415-013-7136-

LCrowdV: Generating Labeled Videos for Simulation-based Crowd Behavior Learning

We present a novel procedural framework to generate an arbitrary number of labeled crowd videos (LCrowdV). The resulting crowd video datasets are used to design accurate algorithms or training models for crowded scene understanding. Our overall approach is composed of two components: a procedural simulation framework for generating crowd movements and behaviors, and a procedural rendering framework to generate different videos or images. Each video or image is automatically labeled based on the environment, number of pedestrians, density, behavior, flow, lighting conditions, viewpoint, noise, etc. Furthermore, we can increase the realism by combining synthetically-generated behaviors with real-world background videos. We demonstrate the benefits of LCrowdV over prior lableled crowd datasets by improving the accuracy of pedestrian detection and crowd behavior classification algorithms. LCrowdV would be released on the WWW

A patient with typical clinical features of mitochondrial encephalopathy, lactic acidosis and stroke-like episodes (MELAS) but without an obvious genetic cause: a case report

<p>Abstract</p> <p>Introduction</p> <p>There are currently 23 missense point mutations and one 4 basepair deletion spanning different mitochondrial genes associated with mitochondrial encephalopathy, lactic acidosis and stroke-like episodes (MELAS). The spectrum of mitochondrial DNA mutations in Arab patients with MELAS is largely unknown.</p> <p>Case presentation</p> <p>A standard clinical examination was carried out on a 34-year-old Saudi woman showing clinical features of MELAS. Fresh frozen muscle tissue was subjected to enzyme histochemical analysis. DNA was extracted from her leukocytes and muscle tissue, and the full mitochondrial genome was screened for base substitution mutations and deletions. Additionally, we screened the polymerase gamma-1 nuclear gene for mutations. The patient was negative for the most common m.3243 A>G MELAS mutation. Sequencing the full mitochondrial genome did not reveal any known or potentially pathogenic sequence changes. The polymerase gamma-1 gene was also free from mutations.</p> <p>Conclusion</p> <p>The clinical picture described here typically fits that observed in patients with MELAS or mitochondrial stroke-like events, but mutations in recognized genes (mitochondrial DNA and polymerase gamma-1 gene) were absent. We report the case of a patient with typical clinical features of MELAS, but without an obvious genetic cause.</p

Heterogeneous determinants of quality of life in different phenotypes of Parkinson's disease

Objectives Health-related quality of life (HRQoL) is considered a very important outcome indicator in patients with Parkinson's disease (PD). A broad list of motor and non-motor features have been shown to affect HRQoL in PD, however, there is a dearth of information about the complexity of interrelationships between determinants of HRQoL in different PD phenotypes. We aimed to find independent determinates and the best structural model for HRQoL, also to investigate the heterogeneity in HRQoL between PD patients with different phenotypes regarding onset-age, progression rate and dominant symptom. Methods A broad spectrum of demographic, motor and non-motor characteristics were collected in 157 idiopathic PD patients, namely comorbidity profile, nutritional status, UPDRS (total items), psychiatric symptoms (depression, anxiety), fatigue and psychosocial functioning through physical examination, validated questionnaires and scales. Structural equation model (SEM) and multivariate regressions were applied to find determinants of Parkinson's disease summary index (PDSI) and different domains of HRQoL (PDQ-39). Results Female sex, anxiety, depression and UPDRS-part II scores were the significant independent determinants of PDSI. A structural model consisting of global motor, global non-motor and co-morbidity indicator as three main components was able to predict 89 of the variance in HRQoL. In older-onset and slow-progression phenotypes, the motor domain showed smaller contribution on HRQoL and the majority of its effects were mediated through non-motor features. Comorbidity component was a significant determinant of HRQoL only among older-onset and non-tremor-dominant PD patients. Fatigue was not a significant indicator of non-motor component to affect HRQoL in rapid-progression PD. Conclusions Our findings showed outstanding heterogeneities in the pattern and determinants of HRQoL among PD phenotypes. These factors should be considered during the assessments and developing personalized interventions to improve HRQOL in PD patients with different phenotypes or prominent feature. © 2015 Fereshtehnejad et al

Mechanisms for the control of local tissue blood flow during thermal interventions: influence of temperature-dependent ATP release from human blood and endothelial cells

© 2016 The Authors. Local tissue perfusion changes with alterations in temperature during heating and cooling, but the thermosensitivity of the vascular ATP signalling mechanisms for control of blood flow during thermal interventions remains unknown. Here we tested the hypotheses that the release of the vasodilator mediator ATP from human erythrocytes, but not from endothelial cells or other blood constituents, is sensitive to both increases and reductions in temperature and that increasing intravascular ATP availability with ATP infusion would potentiate thermal hyperaemia in limb tissues. We first measured blood temperature (Tb), brachial artery blood flow (BABF) and plasma [ATP] during passive arm heating and cooling in healthy males and found they increased by 3.0 ± 1.2 ºC, 105 ± 25 ml min-1 °C-1 and 2-fold (all P<0.05) with heating, but decreased or remained unchanged with cooling. In additional males, intrabrachial artery ATP infusion increased skin and deep tissue perfusion to levels equal or above thermal hyperaemia. In isolated erythrocyte samples exposed to different temperatures, ATP release increased 1.9-fold from 33°C to 39°C (P<0.05) and declined by ~50% at 20°C (P<0.05), but no changes were observed in cultured human endothelial cells, plasma or serum samples. In conclusion, increases in plasma [ATP] and skin and deep tissue perfusion with limb heating are associated with elevations in ATP release from erythrocytes, but not from endothelial cells or other blood constituents. Erythrocyte ATP release is also sensitive to temperature reductions, suggesting erythrocytes may function as thermal sensors and ATP signalling generators for tissue perfusion control during thermal interventions

Cephalometric norms for the Saudi children living in the western region of Saudi Arabia: a research report

BACKGROUND: Previous studies have established specific cephalometric norms for children with different ethnic backgrounds, showing different facial features for each group. Up till now, there is a paucity of information about the cephalometric features of Saudi children living in the western region of Saudi Arabia, who have distinct social and climatic characteristics. The aim of the present study was to establish cephalometric norms for children living in the western region of Saudi Arabia. METHODS: A total of 62 lateral cephalometric radiographs of Saudis (33 females and 29 males; aged 9–12 years) having good facial proportions and Class I dental occlusion, were traced and analyzed. Using the t-test, the mean value, standard deviation and the range of 20 angular and linear variables were calculated and compared to norms of adult Saudis living in the Western region of Saudi Arabia using the t-test. Male and female groups were also compared using the t- test. RESULTS: Saudi children tend to have a significantly shorter and lower face height, a larger angle of convexity, and more proclined and protruded incisors when compared with adult Saudis (P < 0.05). There were no statistically significant differences between male and female groups. CONCLUSION: Saudi children have distinct cephalometric features, which should be used as a reference in the orthodontic treatment of young Saudi patients

Ambulatory heart rate range predicts mode-specific mortality and hospitalisation in chronic heart failure

Objective: We aimed to define the prognostic value of the heart rate range during a 24 h period in patients with chronic heart failure (CHF). Methods: Prospective observational cohort study of 791 patients with CHF associated with left ventricular systolic dysfunction. Mode-specific mortality and hospitalisation were linked with ambulatory heart rate range (AHRR; calculated as maximum minus minimum heart rate using 24 h Holter monitor data, including paced and non-sinus complexes) in univariate and multivariate analyses. Findings were then corroborated in a validation cohort of 408 patients with CHF with preserved or reduced left ventricular ejection fraction. Results: After a mean 4.1 years of follow-up, increasing AHRR was associated with reduced risk of all-cause, sudden, non-cardiovascular and progressive heart failure death in univariate analyses. After accounting for characteristics that differed between groups above and below median AHRR using multivariate analysis, AHRR remained strongly associated with all-cause mortality (HR 0.991/bpm increase in AHRR (95% CI 0.999 to 0.982); p=0.046). AHRR was not associated with the risk of any non-elective hospitalisation, but was associated with heart-failure-related hospitalisation. AHRR was modestly associated with the SD of normal-to-normal beats (R2=0.2; p<0.001) and with peak exercise-test heart rate (R2=0.33; p<0.001). Analysis of the validation cohort revealed AHRR to be associated with all-cause and mode-specific death as described in the derivation cohort. Conclusions: AHRR is a novel and readily available prognosticator in patients with CHF, which may reflect autonomic tone and exercise capacity

Achondroplasia manifesting as enchondromatosis and ossification of the spinal ligaments: a case report

<p>Abstract</p> <p>Introduction</p> <p>A girl presented with achondroplasia manifested as mild knee pain associated with stiffness of her back. A skeletal survey showed enchondroma-like metaphyseal dysplasia and ossification of the spinal ligaments. Magnetic resonance imaging of the spine further clarified the pathological composites.</p> <p>Case presentation</p> <p>A 7-year-old girl presented with the classical phenotypic features of achondroplasia. Radiographic documentation showed the co-existence of metaphyseal enchondromatosis and development of spinal bony ankylosis. Magnetic resonance imaging showed extensive ossification of the anterior and posterior spinal ligaments. Additional features revealed by magnetic resonance imaging included calcification of the peripheral vertebral bodies associated with anterior end-plate irregularities.</p> <p>Conclusion</p> <p>Enchondromas are metabolically active and may continue to grow and evolve throughout the patient's lifetime; thus, progressive calcification over a period of years is not unusual. Ossification of the spinal ligaments has a specific site of predilection and often occurs in combination with senile ankylosing vertebral hyperostosis. Nevertheless, ossification of the spinal ligaments has been encountered in children with syndromic malformation complex. It is a multifactorial disease in which complex genetic and environmental factors interact, potentially leading to chronic pressure on the spinal cord and nerve roots with subsequent development of myeloradiculopathy. Our patient presented with a combination of achondroplasia, enchondroma-like metaphyseal dysplasia and calcification of the spinal ligaments. We suggest that the development of heterotopic bone formation along the spinal ligaments had occurred through an abnormal ossified enchondral mechanism. We postulate that ossification of the spinal ligaments and metaphyseal enchondromatous changes are related to each other and represent impaired terminal differentiation of chondrocytes in this particular case. Standard radiographic examination showed spinal bony ankylosis only. The pathological composites of the vertebrae have been clarified using scanning technology. Extensive spinal ligament ossification associated with calcification of the peripheral vertebral bodies and anterior end-plate irregularities were notable. We report what may be a novel spinal and extraspinal malformation complex in a girl with achondroplasia.</p

Primary central nervous system lymphoma presenting as a pure third ventricular lesion: a case report

<p>Abstract</p> <p>Introduction</p> <p>Primary central nervous system lymphomas are infrequently occurring lymphomas that account for only 0.3-1.5% of all intra-cranial neoplasms in patients without acquired immune deficiency syndrome. However, a pure third ventricle lymphoma is extremely rare. Here, we discuss the similar radiological appearances of lesions localized in the third ventricle and the importance of accurately diagnosing primary central nervous system lymphomas for favorable treatment outcomes.</p> <p>Case presentation</p> <p>A 38-year-old Caucasian man from Turkey presented with a severe headache lasting for three months that failed to respond to any medication. Both severity and duration of the symptoms increased gradually, resulting in vomiting, nausea and gait disturbance that accompanied the headache for three weeks. Neuro-imaging studies showed a lesion located solely in the third ventricle, resulting in partial obstruction of the foramen of Monro. The pre-operative diagnosis was a colloid cyst. Following the surgical procedure, the results of pathological and immunochemical assays revealed that the pre-operative diagnosis was incorrect and that the lesion was a primary central system lymphoma.</p> <p>Conclusion</p> <p>Pure third ventricle lymphomas are extremely rare and are exceptionally localized. It is important to be aware of, and to differentiate between, other possible third ventricular lesions that may mimic the same radiological appearance. Accurate diagnosis is necessary for selecting appropriate treatment modalities.</p