Blood-retinal barrier as a converging pivot in understanding the initiation and development of retinal diseases / 中华医学杂志(英文版)

Clinical ophthalmologists consider each retinal disease as a completely unique entity. However, various retinal diseases, such as uveitis, age-related macular degeneration, diabetic retinopathy, and primary open-angle glaucoma, share a number of common pathogenetic pathways. Whether a retinal disease initiates from direct injury to the blood-retinal barrier (BRB) or a defect/injury to retinal neurons or glia that impairs the BRB secondarily, the BRB is a pivotal point in determining the prognosis as self-limiting and recovering, or developing and progressing to a clinical phenotype. The present review summarizes our current knowledge on the physiology and cellular and molecular pathology of the BRB, which underlies its pivotal role in the initiation and development of common retinal diseases.

Quantitative determination of febrifugine by proton nuclear magnetic resonance spectroscopy with internal standard method / 中国中药杂志

A quantitative nuclear magnetic resonance method(qNMR) was established for determination of the absolute content of febrifugine. Proton nuclear magnetic resonance spectroscopy of febrifugine was obtained in DMSO-d₆ with hydroquinone as the internal standard substance on a Bruker Ascend 600 MHz superconducting nuclear resonance spectrometer at 298 K. The specific parameters were as follows: the observing frequency was 600 MHz,spectra width was 7 211 Hz, pulse width was 9.70 μs, pulse sequence was zg30,scan times was 32 and relaxation time was 2 s. The proton signal peaked at δ 7.71 for febrifugine and δ 6.55 for hydroquinone were selected as the quantification peaks. Linear regression of quantitative peak area ratio of febrifugine-hydroquinone versus their mass ratio yielded a correlation coefficient of 0.999 6 and a regression equation of +0.008 6．The linear range of febrifugine was 2.17-17.07 g·L⁻¹,the precision RSD was 0.78%(=6),the repeatability RSD was 1.2%(=6),and the contents of three batches of febrifugine sample were 94.91%,95.09% and 95.52%,respectively. The content of febrifugine was 96.44% determined by high performance liquid chromatography(HPLC). The relative error of the content of febrigugine determinted by qNMR and HPLC methods was 1.27%. The results showed that the internal standard method of proton nuclear magnetic resonance spectroscopy could be used to determine the absolute content of febrifugine.

Blood loss closely correlates with body mass index in total hip arthroplasty performed through direct lateral approach

To investigate total blood loss [TBL], intraoperative blood loss [IBL], post-operative drainage [POD], and other related variables in total hip arthroplasty [THA] performed through direct lateral approach. This study was completed in Shanghai Sixth People's Hospital, Shanghai, China, between January and December 2010. We analyzed 113 patients treated by THA through direct lateral approach. Recordable blood loss [RBL] was measured and TBL was calculated according to the Gross formula. Ordinal logistic regression analysis was used for TBL, IBL, and POD, with gender, age, body mass index [BMI], disease duration, and operative time as independent variables. The average operative time was 51.5 +/- 10.4 [range: 35-70] minutes, with an average RBL of 454 +/- 144 [range: 150-180] ml. Average TBL was significantly higher [975 +/- 355, range: 430-2020 ml; p<0.001]. In the analysis of variables, BMI closely correlated with TBL, IBL, and POD, with odds ratios of 4.80 [95% CI: 2.63-8.78 [TBL]], 5.39 [95% CI: 2.84-10.25 [IBL]], and 4.37 [95% CI: 2.43-7.89 [POD]]. Moreover, TBL [54.172], IBL [55.198], and POD [39.139] correlated with trend test BMI. The TBL, IBL, and POD closely correlate with BMI in patients undergoing THA through direct lateral approach

Correlation study on biomechanics of three-foot weight bearing canine model with femoral head osteonecrosis / 医用生物力学

Objective To study changes in biomechanical characteristics of the femoral head during the progression of avascular osteonecrosis and investigate the mechanism of these biomechanical changes. Methods Twenty-four three-foot weight bearing canine models with osteonecrosis of the femoral head (ONFH) were established by fixing one fore limb of the canine. Osteonecrosis was induced in all experimental animals by randomly injecting 5 mL pure ethanol into one side of the femoral head, and the contralateral femoral head was injected with an equal amount of normal saline as the control group. The canines were killed at 1st, 3rd, 6th, and 12th week after the injection of ethanol, with six canines in each group. The radiographic, histological changes and biomechanical characteristics of the femoral head were observed and analyzed. Results At 3rd week, 29% reduction of indentation stiffness and 32.9% reduction of elastic modulus in the cancellous bone were found in the infected femoral heads compared to the control heads, and a low density area was detected only in MRI and osteonecrosis was the main histological characteristics. At 6th and 12th week, the indentation stiffness in the infected femoral heads was reduced by 45.5% and 48.7%, respectively, and the elastic modulus of the cancellous bone in the infected femoral heads was reduced by 34.1% and 32.4%, respectively, compared to the control heads. At 6th week, uneven bone density of the femoral head was detected in radiographs, and the progression of osteonecrosis and bone healing was found at the same time. At 12th week, areas of reduced bone mineral density beneath the load bearing position of the femoral head were observed on radiographs. Collapse of the articular cartilage surface and narrowing of the joint space were the main histological findings. Conclusions Biomechanics is an important factor in the progression of ONFH. The decreased mechanical properties may be a direct reason leading to the late collapse of the femoral head. The treatment of ONFH should focus not only on acceleration of the bone healing, but also on provision of a favorable and stable biomechanical environment for the infected femoral head.

A biological treatment technique for wool textile

A biological treatment technique for wool textile was carried out by enzymes degradation coupled with H2O2 oxidation. The results demonstrated that the technique had ideal effects on wool textile such as better softness, plump and less loss of bursting stress. Because of mild reaction conditions, less textile damage and less environmental pollution, this technique for wool textile treatment could have promising prospect.

Relationship between the patients' knowledge on hypertension prevention and control and the rate on blood pressure control / 中华流行病学杂志

<p><b>OBJECTIVE</b>To study the relationship between blood pressure control status and patients' knowledge on hypertension prevention and control among hypertensive patients.</p><p><b>METHODS</b>A total of 726 hypertensives were selected from four community health service centers (2 urban and 2 rural) in Beijing. All subjects were investigated by questionnaires and their blood pressures were measured at the same time.</p><p><b>RESULTS</b>The rate for blood pressure under control (< 140/90 mm Hg, 1 mm Hg = 0.133 kPa) in the rural and urban patients were 46.4% and 23.9% respectively. The control rate increased with the increase of patients' knowledge on prevention and control of hypertension in both urban and rural patients. The cumulative effect of knowledge on hypertension control status could contribute 30.0% to the difference in hypertension control rate between rural and urban patients.</p><p><b>CONCLUSION</b>Patients' knowledge on hypertension control was significantly related to the rate on hypertension control. Health education should be helpful to improve the rate on hypertension control.</p>