4,035 research outputs found
Comparison of Pressures Applied by Digital Tourniquets in the Emergency Department
Background: Digital tourniquets used in the emergency department have been scrutinized due to complications associated with their use, including neurovascular injury secondary to excessive tourniquet pressure and digital ischemia caused by a forgotten tourniquet. To minimize these risks, a conspicuous tourniquet that applies the least amount of pressure necessary to maintain hemostasis is recommended.Objective: To evaluate the commonly used tourniquet methods, the Penrose drain, rolled glove, the Tourni-cot and the T-Ring, to determine which applies the lowest pressure while consistently preventing digital perfusion.Methods: We measured the circumference of selected digits of 200 adult males and 200 adult females to determine the adult finger size range. We then measured the pressure applied to four representative finger sizes using a pressure monitor and assessed the ability of each method to prevent digital blood flow with a pulse oximeter.Results: We selected four representative finger sizes: 45mm, 65mm, 70mm, and 85mm to test the different tourniquet methods. All methods consistently prevented digital perfusion. The highest pressure recorded for the Penrose drain was 727 mmHg, the clamped rolled glove 439, the unclamped rolled glove 267, Tourni-cot 246, while the T-Ring had the lowest at 151 mmHg and least variable pressures of all methods.Conclusion: All tested methods provided adequate hemostasis. Only the Tourni-cot and T-Ring provided hemostasis at safe pressures across all digit sizes with the T-Ring having a lower overall average pressure. [West J Emerg Med. 2011;12(2):242-249.
Association of Blood Pressure With Stroke Risk, Stratified by Age and Stroke Type, in a Low-Income Population in China: A 27-Year Prospective Cohort Study
Association of stroke risk with new blood pressure criterion 2017 is unknown in China. We assessed the association between blood pressure (BP) values and stroke risk in a low-income population in Tianjin, China. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) values were categorized into five strata and strokes were recorded as stroke, ischemic stroke, and hemorrhagic stroke. Stroke risk was analyzed according to blood pressure stratum using Cox regression analysis. Overall, 4,017 residents (age, ≥18 years) were included in this prospective cohort study. Over a 27-year follow-up period (total, 86,515.78 person-years), 638 participants experienced first-ever strokes. The stroke risk was higher among individuals with SBPs ≥140 mmHg or DBPs ≥90 mmHg than among those with SBPs < 130 mmHg or DBPs < 80 mmHg (reference group), after adjusting for covariates. However, hemorrhagic stroke risk increased only in participants with SBPs ≥160 mmHg. The stroke risk increased for individuals < 65-years-old having BP values ≥130/80 mmHg and for individuals ≥65-years-old with BP values ≥160/90 mmHg. To reduce the stroke burden in China, target BP goals must be established for adults, with different targets for the middle-aged and the elderly segments of the population. These results are very important for guiding clinical practice and may be generalized to other developing countries experiencing rapid economic development and where transitions in the spectrum of prevalent diseases have occurred
Sex Differences in the Prevalence, Awareness, Treatment, and Control of Diabetes Mellitus Among Adults Aged 45 Years and Older in Rural Areas of Northern China: A Cross-Sectional, Population-Based Study
Aims: Diabetes mellitus (DM) has reached epidemic proportions among adults worldwide, with China having the world's largest population of individuals with the disease. Although the consequences of low rates of awareness, treatment, and control of DM are understood, sex-related differences in these rates remain unknown. We assessed sex-related differences in the prevalence, awareness, treatment, and control of DM in a low-income, rural population in China.Materials and Methods: Individuals ≥45 years old without cardiovascular disease were recruited into this study. The prevalence, awareness, treatment, and control of DM in both men and women were assessed after accounting for age, educational level, body mass index, and blood pressure.Results: A total of 3,725 participants (women, 58.8%) were included. A male preponderance in the prevalence of DM was found among individuals aged 45–54 years, whereas there was a female preponderance among patients aged 65–74 years and among those who were illiterate. Among individuals with >6 years of formal education, overweight individuals, and normotensive individuals, there was greater DM awareness among women than among men. There was also a higher DM treatment rate among overweight women than among overweight men. However, better disease control was observed among men than among women for individuals aged 55–64-years, those with 1–6 years of education, and those with stage II hypertension.Conclusions: These results suggest that DM awareness should be improved among men and that regular DM screening should be implemented for men, especially young men. In addition, disease education and management should be strengthened for elderly women, especially those with low levels of education. Further studies are necessary to explore this situation among a representative population sample in China in order to establish a valid protocol against DM
-SUP: A clustering algorithm for cryo-electron microscopy images of asymmetric particles
Cryo-electron microscopy (cryo-EM) has recently emerged as a powerful tool
for obtaining three-dimensional (3D) structures of biological macromolecules in
native states. A minimum cryo-EM image data set for deriving a meaningful
reconstruction is comprised of thousands of randomly orientated projections of
identical particles photographed with a small number of electrons. The
computation of 3D structure from 2D projections requires clustering, which aims
to enhance the signal to noise ratio in each view by grouping similarly
oriented images. Nevertheless, the prevailing clustering techniques are often
compromised by three characteristics of cryo-EM data: high noise content, high
dimensionality and large number of clusters. Moreover, since clustering
requires registering images of similar orientation into the same pixel
coordinates by 2D alignment, it is desired that the clustering algorithm can
label misaligned images as outliers. Herein, we introduce a clustering
algorithm -SUP to model the data with a -Gaussian mixture and adopt
the minimum -divergence for estimation, and then use a self-updating
procedure to obtain the numerical solution. We apply -SUP to the
cryo-EM images of two benchmark macromolecules, RNA polymerase II and ribosome.
In the former case, simulated images were chosen to decouple clustering from
alignment to demonstrate -SUP is more robust to misalignment outliers
than the existing clustering methods used in the cryo-EM community. In the
latter case, the clustering of real cryo-EM data by our -SUP method
eliminates noise in many views to reveal true structure features of ribosome at
the projection level.Comment: Published in at http://dx.doi.org/10.1214/13-AOAS680 the Annals of
Applied Statistics (http://www.imstat.org/aoas/) by the Institute of
Mathematical Statistics (http://www.imstat.org
Determinants of Developing Stroke Among Low-Income, Rural Residents: A 27-Year Population-Based, Prospective Cohort Study in Northern China
Although strokes are the leading cause of death and disability in many countries, China still lacks long-term monitoring data on stroke incidence and risk factors. This study explored stroke risk factors in a low-income, rural population in China. The study population was derived from the Tianjin Brain Study, a population-based stroke monitoring study that began in 1985. This study documented the demographic characteristics, past medical histories, and personal lifestyles of the study participants. In addition, physical examinations, including measurements of blood pressure (BP), height, and weight, were performed. Hazard ratios (HRs) were estimated for the risk factors for all subtypes of stroke using multivariate Cox regression analyses. During the study with mean following-up time of 23.16 years, 3906 individuals were recruited at baseline, and during 27 years of follow-up, 638 strokes were documented. The multivariate Cox regression analyses revealed a positive correlation between age and stroke incidence. Limited education was associated with a 1.9-fold increase in stroke risk (lowest vs. highest education level). Stroke risk was higher among former smokers than among current smokers (HR, 1.8 vs. 1.6; both, P < 0.05). Moreover, stroke risk was significantly associated with sex (HR, 1.8), former alcohol drinking (HR, 2.7), baseline hypertension (HR, 3.1), and overweight (HR, 1.3). In conclusion, this study identified uncontrollable (sex and age) and controllable (education, smoking, alcohol drinking, hypertension, and overweight) risk factors for stroke in a low-income, rural population in China. Therefore, it is critical to control BP and weight effectively, advocate cessation of smoking/alcohol drinking, and enhance the education level in this population to prevent increase in the burden of stroke in China
Optimization of venous return tubing diameter for cardiopulmonary bypass
Objective: To determine the optimal venous tubing diameter for adult cardiopulmonary bypass (CPB) to improve gravity drainage and to reduce priming volume. Methods: (A) Maximum bovine blood flow rates by gravity drainage were assessed in vitro for four different tubing diameters (1/2, 3/8, 5/16,1/4 inch) with three different lengths and various pre- and afterloads. Based on the results of (A) and multiple regression analyses, we developed equations to predict tubing sizes as a function of target flows. (C) The equations obtained in (B) were validated by ex vivo bovine experiments. (D) The clinically required maximal flows were determined retrospectively by reviewing 119 perfusion records at Zurich University. (E) Based on our model (B), the clinical patient and hardware requirements, the optimal venous tubing diameter was calculated. (F) The optimized venous tubing was evaluated in a prospective clinical trial involving 312 patients in Hangzhou. Results: For a mean body surface area of 1.83±0.2 m2, the maximal perfusion flow rate (D) achieved with 1/2-inch (=1.27 cm2) venous tubing was 4.62±0.57 l/min (range: 2.50-6.24 l/min). Our validated model (B,C) predicted 1.0 cm2 as optimal cross-sectional area for the venous line. New tubing packs developed accordingly were used routinely thereafter. The maximal flow rate was 4.93±0.58 l/min (range: 3.9-7.0) in patients with a mean body surface area of 1.62±0.21 m2. Conclusion: The new venous tubing with 1.0-cm2 cross-sectional area improves the drainage in the vast majority of adult patients undergoing CPB and reduces the priming volume (−27 ml/m). Reduced hemodilution can prevent homologous transfusions if a predefined transfusion trigger level is not reache
Genistein-3′-sulfonic acid dihydrate
In the title compound [systematic name: 5-(5,7-dihydrÂoxy-4-oxo-4H-chromenÂyl)-2-hydroxyÂbenzeneÂsulfonic acid dihydrate], C15H10O8S·2H2O, the benzopyranÂone ring is not coplanar with the phenyl ring, the dihedral angle between them being 41.35 (3)°. No H atom was placed on the sulphonic acid group because it was not possible to distinguish between the two S=O bonds and the S—O bond. In the crystal, the molÂecules are linked by classical O—H⋯O and C—H⋯O intra- and interÂmolecular hydrogen bonds and aromatic π–π stacking interÂactions [centroid–centroid distance of 3.4523 (14) Å between the 1, 4-pyranÂone rings and the benzene rings, and 3.6337 (14) Å between the benzene rings] into a supraÂmolecular structure
- …