2,136 research outputs found
Should physical activity recommendations be ethnicity-specific? Evidence from a cross-sectional study of south Asian and European men
Background
Expert bodies and health organisations recommend that adults undertake at least 150 min.week−1 of moderate-intensity physical activity (MPA). However, the underpinning data largely emanate from studies of populations of European descent. It is unclear whether this level of activity is appropriate for other ethnic groups, particularly South Asians, who have increased cardio-metabolic disease risk compared to Europeans. The aim of this study was to explore the level of MPA required in South Asians to confer a similar cardio-metabolic risk profile to that observed in Europeans undertaking the currently recommended MPA level of 150 min.week−1.<p></p>
Methods
Seventy-five South Asian and 83 European men, aged 40–70, without cardiovascular disease or diabetes had fasted blood taken, blood pressure measured, physical activity assessed objectively (using accelerometry), and anthropometric measures made. Factor analysis was used to summarise measured risk biomarkers into underlying latent ‘factors’ for glycaemia, insulin resistance, lipid metabolism, blood pressure, and overall cardio-metabolic risk. Age-adjusted regression models were used to determine the equivalent level of MPA (in bouts of ≥10 minutes) in South Asians needed to elicit the same value in each factor as Europeans undertaking 150 min.week−1 MPA.<p></p>
Findings
For all factors, except blood pressure, equivalent MPA values in South Asians were significantly higher than 150 min.week−1; the equivalent MPA value for the overall cardio-metabolic risk factor was 266 (95% CI 185-347) min.week−1.<p></p>
Conclusions
South Asian men may need to undertake greater levels of MPA than Europeans to exhibit a similar cardio-metabolic risk profile, suggesting that a conceptual case can be made for ethnicity-specific physical activity guidance. Further study is needed to extend these findings to women and to replicate them prospectively in a larger cohort.<p></p>
Síndrome erosivo ulceroso gástrico asociado a estrés en una danta (Tapirus terrestris): Reporte de un caso en Venezuela
The aim of this study was to report of gastric ulcer syndrome associated with erosive stress in Venezuela in a Tapir (Tapirus terrestris) Sex male, 6 years old with a history of anorexia, depression, collapse, shock and death. It is practical histology (necropsy and histopathology). Under conditions of captivity at the Zoo "El Pinar"; in Caracas, Venezuela. Sections of gastric mucosa were taken in all regions (cardiac, fundic and pyloric), being set at 10% formalin, processed by conventional methods of histological processing. The results were macroscopic gaseous gastric dilation, chronic erosive, gastritis and ulcer focal line type of the cardiac region and of the bottom of the stomach, focal parakeratotic hyperkeratosis in the cardiac region. The histology of gastric mucosa showed erosive gastritis and chronic with ulcer characterized by lymphocytic infiltration in the (lamina propria), with varying degree of exposure of the submucosa. The morphometric study revealed gastric mucosal epithelial loss gastric fundic region. The average damage was 220.21 ± 30.28 µm. In conclusion a case was reported chronic erosive gastritis in a tapir associated with stress.Con el objetivo de describir y reportar el síndrome erosivo ulceroso gástrico asociado a estrés en Venezuela en una danta (Tapirus terrestris) de sexo macho, de 6 años de edad, con antecedentes de anorexia, depresión, colapso, shock y muerte. Se practico un estudio anatomopatológico (técnica de necropsia e histopatología). Bajo condiciones de cautiverio en el Zoológico "El Pinar" de Caracas, Venezuela. Secciones de mucosas gástrica fueron tomadas en todas sus regiones (cardial, fundica y pilórica), siendo fijadas a formalina al 10%, procesándolas por los métodos convencionales de procesamiento histológico. Los resultados macroscópicos fueron dilatación gástrica gaseosa, gastritis crónica erosiva con microulceras focales y ulceras tipo lineales desde la región cardial hasta el fondo del estomago, hiperqueratosis paraqueratotica focal en la región cardial. Los cortes histológicos de mucosa gástrica evidenciaron gastritis crónica erosiva y ulcerosa caracterizada por un infiltrado linfocitario en la (lamina propia), con grado variable de exposición de la submucosa. El estudio morfométrico de mucosa gástrica revelo pérdida del epitelio gástrico en la región fundica. El promedio de daño fue de 220,21± 30,28 µm. En conclusión se reporto un caso gastritis crónica erosiva ulcerosa en una danta asociado a estrés
Inhibition of protein N-myristoylation blocks Plasmodium falciparum intraerythrocytic development, egress and invasion
We have combined chemical biology and genetic modification approaches to investigate the importance of protein myristoylation in the human malaria parasite, Plasmodium falciparum. Parasite treatment during schizogony in the last 10 to 15 hours of the erythrocytic cycle with IMP-1002, an inhibitor of N-myristoyl transferase (NMT), led to a significant blockade in parasite egress from the infected erythrocyte. Two rhoptry proteins were mislocalized in the cell, suggesting that rhoptry function is disrupted. We identified 16 NMT substrates for which myristoylation was significantly reduced by NMT inhibitor (NMTi) treatment, and, of these, 6 proteins were substantially reduced in abundance. In a viability screen, we showed that for 4 of these proteins replacement of the N-terminal glycine with alanine to prevent myristoylation had a substantial effect on parasite fitness. In detailed studies of one NMT substrate, glideosome-associated protein 45 (GAP45), loss of myristoylation had no impact on protein location or glideosome assembly, in contrast to the disruption caused by GAP45 gene deletion, but GAP45 myristoylation was essential for erythrocyte invasion. Therefore, there are at least 3 mechanisms by which inhibition of NMT can disrupt parasite development and growth: early in parasite development, leading to the inhibition of schizogony and formation of "pseudoschizonts," which has been described previously; at the end of schizogony, with disruption of rhoptry formation, merozoite development and egress from the infected erythrocyte; and at invasion, when impairment of motor complex function prevents invasion of new erythrocytes. These results underline the importance of P. falciparum NMT as a drug target because of the pleiotropic effect of its inhibition
Recovery of renal function in dialysis patients
BACKGROUND: Although recovery of renal functions in dialysis dependent patients is estimated to be greater than 1%, there are no indicators that actually suggest such revival of renal function. Residual renal function in dialysis patients is unreliable and seldom followed. Therefore renal recovery (RR) in dialysis dependent patients may remain unnoticed. We present a group of dialysis dependent patients who regained their renal functions. The aim of this project is to determine any indicators that may identify the recovery of renal functions in dialysis dependent patients. METHODS: All the discharges from the chronic dialysis facilities were identified. Among these discharges deaths, transplants, voluntary withdrawals and transfers either to another modality or another dialysis facility were excluded in order to isolate the patients with RR. The dialysis flow sheets and medical records of these patients were subsequently reviewed. RESULTS: Eight patients with a mean age of 53.8 ± 6.7 years (± SEM) were found to have RR. Dialysis was initiated due to uremic symptoms in 6 patients and fluid overload in the remaining two. The patients remained dialysis dependent for 11.1 ± 4.2 months. All these patients had good urine output and 7 had symptoms related to dialysis. Their mean pre-initiation creatinine and BUN levels were 5.21 ± 0.6 mg/dl and 72.12 ± 11.12 mg/dl, respectively. Upon discontinuation, they remained dialysis free for 19.75 ± 5.97 months. The mean creatinine and BUN levels after cessation of dialysis were 2.85 ± 0.57 mg/dl and 29.62 ± 5.26 mg/dl, respectively, while the mean creatinine clearance calculated by 24-hour urine collection was 29.75 ± 4.78 ml/min. One patient died due to HIV complications. One patient resumed dialysis after nine months. Remaining continue to enjoy a dialysis free life. CONCLUSION: RR must be considered in patients with good urine output and unresolved acute renal failure. Dialysis intolerance may be an indicator of RR among such patients
Can luteal regression be reversed?
The corpus luteum is an endocrine gland whose limited lifespan is hormonally programmed. This debate article summarizes findings of our research group that challenge the principle that the end of function of the corpus luteum or luteal regression, once triggered, cannot be reversed. Overturning luteal regression by pharmacological manipulations may be of critical significance in designing strategies to improve fertility efficacy
Aharonov-Bohm interference in topological insulator nanoribbons
Topological insulators represent novel phases of quantum matter with an
insulating bulk gap and gapless edges or surface states. The two-dimensional
topological insulator phase was predicted in HgTe quantum wells and confirmed
by transport measurements. Recently, Bi2Se3 and related materials have been
proposed as three-dimensional topological insulators with a single Dirac cone
on the surface and verified by angle-resolved photoemission spectroscopy
experiments. Here, we show unambiguous transport evidence of topological
surface states through periodic quantum interference effects in layered
single-crystalline Bi2Se3 nanoribbons. Pronounced Aharonov-Bohm oscillations in
the magnetoresistance clearly demonstrate the coverage of two-dimensional
electrons on the entire surface, as expected from the topological nature of the
surface states. The dominance of the primary h/e oscillation and its
temperature dependence demonstrate the robustness of these electronic states.
Our results suggest that topological insulator nanoribbons afford novel
promising materials for future spintronic devices at room temperature.Comment: 5 pages, 4 figures, RevTex forma
Chirped pulse Raman amplification in warm plasma: towards controlling saturation
Stimulated Raman backscattering in plasma is potentially an efficient method of amplifying laser pulses to reach exawatt powers because plasma is fully broken down and withstands extremely high electric fields. Plasma also has unique nonlinear optical properties that allow simultaneous compression of optical pulses to ultra-short durations. However, current measured efficiencies are limited to several percent. Here we investigate Raman amplification of short duration seed pulses with different chirp rates using a chirped pump pulse in a preformed plasma waveguide. We identify electron trapping and wavebreaking as the main saturation mechanisms, which lead to spectral broadening and gain saturation when the seed reaches several millijoules for durations of 10's - 100's fs for 250 ps, 800 nm chirped pump pulses. We show that this prevents access to the nonlinear regime and limits the efficiency, and interpret the experimental results using slowly-varying-amplitude, current-averaged particle-in-cell simulations. We also propose methods for achieving higher efficiencies.close0
Alpha-N: Shortest Path Finder Automated Delivery Robot with Obstacle Detection and Avoiding System
Alpha N A self-powered, wheel driven Automated Delivery Robot is presented in
this paper. The ADR is capable of navigating autonomously by detecting and
avoiding objects or obstacles in its path. It uses a vector map of the path and
calculates the shortest path by Grid Count Method of Dijkstra Algorithm.
Landmark determination with Radio Frequency Identification tags are placed in
the path for identification and verification of source and destination, and
also for the recalibration of the current position. On the other hand, an
Object Detection Module is built by Faster RCNN with VGGNet16 architecture for
supporting path planning by detecting and recognizing obstacles. The Path
Planning System is combined with the output of the GCM, the RFID Reading System
and also by the binary results of ODM. This PPS requires a minimum speed of 200
RPM and 75 seconds duration for the robot to successfully relocate its position
by reading an RFID tag. In the result analysis phase, the ODM exhibits an
accuracy of 83.75 percent, RRS shows 92.3 percent accuracy and the PPS
maintains an accuracy of 85.3 percent. Stacking all these 3 modules, the ADR is
built, tested and validated which shows significant improvement in terms of
performance and usability comparing with other service robots.Comment: 12 pages, 7 figures, To be appear in the proceedings of 12th Asian
Conference on Intelligent Information and Database Systems 23-26 March 2020
Phuket, Thailan
Lower cardiorespiratory fitness contributes to increased insulin resistance and fasting glycaemia in middle-aged South Asian compared with European men living in the UK
AIMS/HYPOTHESIS: This study aimed to determine the extent to which increased insulin resistance and fasting glycaemia in South Asian men, compared with white European men, living in the UK, was due to lower cardiorespiratory fitness (maximal oxygen uptake [[Formula: see text]]) and physical activity. METHODS: One hundred South Asian and 100 age- and BMI-matched European men without diagnosed diabetes, aged 40–70 years, had fasted blood taken for measurement of glucose concentration, HOMA-estimated insulin resistance (HOMA(IR)), plus other risk factors, and underwent assessment of physical activity (using accelerometry), [Formula: see text], body size and composition, and demographic and other lifestyle factors. For 13 South Asian and one European man, HbA(1c) levels were >6.5% (>48 mmol/mol), indicating potential undiagnosed diabetes; these men were excluded from the analyses. Linear regression models were used to determine the extent to which body size and composition, fitness and physical activity variables explained differences in HOMA(IR) and fasting glucose between South Asian and European men. RESULTS: HOMA(IR) and fasting glucose were 67% (p < 0.001) and 3% (p < 0.018) higher, respectively, in South Asians than Europeans. Lower [Formula: see text], lower physical activity and greater total adiposity in South Asians individually explained 68% (95% CI 45%, 91%), 29% (11%, 46%) and 52% (30%, 80%), respectively, and together explained 83% (50%, 119%) (all p < 0.001) of the ethnic difference in HOMA(IR). Lower [Formula: see text] and greater total adiposity, respectively, explained 61% (9%, 111%) and 39% (9%, 76%) (combined effect 63% [8%, 115%]; all p < 0.05) of the ethnic difference in fasting glucose. CONCLUSIONS/INTERPRETATION: Lower cardiorespiratory fitness is a key factor associated with the excess insulin resistance and fasting glycaemia in middle-aged South Asian, compared with European, men living in the UK. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00125-013-2969-y) contains peer-reviewed but unedited supplementary material, which is available to authorised users
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