Determination of dimethyl sulfate in workplace air by pre-column derivatization-high performance liquid chromatography / 中国职业医学

@#Abstract: Objective - - To establish a pre column derivatization high performance liquid chromatography method for detecting Methods dimethyl sulfate (DMS) in workplace air. DMS in workplace air was collected with mercaptopyridine impregnated （ silicone tube. The derivative of DMS and mercaptopyridine was eluted by mobile phase phase A: water, phase B: acetonitrile, ∶ the volume ratio was 40 60) , and separated with a C18 column, then detected with diode array detector and quantitated by a Results - standard curve. The linear range of DMS was 0.17 40.00 mg/L, with the correlation coefficient of 0.999 95. The detection limit and the lower limit of quantitation were 0.05 and 0.17 mg/L respectively. The minimum detection concentration and minimum quantitation concentration were 0.02 and 0.04 mg/m³, respectively (air sample volume of 4.5 L, 1.0 mL sample - - - solution). The average desorption efficiency was 98.40% 102.00%. The within run and between run relative standard deviations - - were 0.61% 3.92% and 1.71% 6.00%, respectively. The samples could be stored at room temperature for at least 14 days. Conclusion This method can be used to detect DMS in workplace air.

Muscle mass loss and intermuscular lipid accumulation were associated with insulin resistance in patients receiving hemodialysis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>An accelerated muscle wasting was the pivotal factor for protein-energy wasting in end stage renal disease. However, very few researches have examined the skeletal muscle quantity and quality in clinical patients. This study investigated the muscle morphologic changes by magnetic resonance imaging (MRI) and analyzed the related factors in hemodialysis patients.</p><p><b>METHODS</b>Fifty-eight patients receiving maintenance hemodialysis (HD) were investigated and 28 healthy adults with gender and age matched were used as controls (Control). Anthropometry, cytokine factors, and laboratory data were measured. The muscle and intermuscular adipose tissues (IMAT) were analyzed via a Thigh MRI. The bicep samples were observed after HE staining. Homeostatic model assessment of insulin resistance (HOMA-IR) was measured and their association with muscle wasting was analyzed.</p><p><b>RESULTS</b>HD patients tended to have a lower protein diet, anthropometry data, and serum albumin, but the C reactive protein and interleukin-6 increased significantly. The MRI showed that HD patients had less muscle mass and a lower muscle/total ratio, but the fat/muscle and IMAT was higher when compared to the Control group. The muscle fiber showed atrophy and fat accumulation in the biceps samples come from the HD patients. Moreover, we found that the HD patients presented with a high level of plasma fasting insulin and increased HOMA-IR which negatively correlated with the muscle/total ratio, but positively with the fat/muscle ratio.</p><p><b>CONCLUSIONS</b>Muscle wasting presented early before an obvious malnutrition condition emerged in HD patients. The main morphological change was muscle atrophy along with intermuscular lipid accumulation. Insulin resistance was associated with muscle wasting in dialysis patients.</p>

A multicenter study of mid urethral sling procedures in treatment of female stress urinary incontinence / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the clinical efficacy, surgical indications and postoperative complications of mid urethral sling procedures in treatment of female stress urinary incontinence.</p><p><b>METHODS</b>A multicenter clinical trial was conducted from April 2002 to April 2008 in five hospitals, 304 cases of genuine stress urinary incontinence and 8 cases of mixed incontinence were included. TVT procedures were carried out in 134 patients, TVTO procedures in 167 patients, Monarc procedures in 11 patients. Perioperative evaluations included: operating time, bleeding volume, and perioperative complications. Operative efficacy was classified into three categories: cure, improved and failure and evaluated before discharge, 3 months after surgery and then every year.</p><p><b>RESULTS</b>TVT group had longer operating time [(18.5 + or - 9.6) min] and more bleeding volume [(32.2 + or - 12.6) ml] than those in TVTO group [(11.5 + or - 3.1) min, (12.8 + or - 8.5) ml] and in Monarc group [(11.1 + or - 2.6) min, (12.3 + or - 3.5) ml] with P < 0.05. Monarc and TVTO procedures had higher cure rates and improve rates comparing with TVT, but the differences were of no significance. The cure rate (95.7%) in patients with genuine stress incontinence were significantly higher than that in patients with mixed incontinence (37.5%). No significant differences of total intra- and postoperative complications were noted for all of the three procedures. However, bladder injury tended to occur in TVT group and obturator nerve injury and vaginal injury tended to occur in TVTO group. Transient voiding dysfunction and urinary retention were the most common complications.</p><p><b>CONCLUSIONS</b>Mid urethral sling procedures have excellent clinical outcomes in the treatment of female stress urinary incontinence.</p>

Urodynamic study of neurogenic bladder model after spinal cord injury in rat / 中华物理医学与康复杂志

Objective To observe the urodynamic change after spinal cord injury at different levels and the relationship with neurogenic dysfunction of bladder and urethra. Methods Eighty female rats were divided into a control group (20 rats) , a suprasacral spinal cord injury group (30 rats) and a sacral spinal cord injury (30 rats). The urodynamic exam was performed with all the rats before and 20 days after the spinal cord injury model was established by surgical operation. Results The maximum bladder volume and compliance in the su- prasacral injury group were significantly less than the sacral spinal cord injury group and the control, the maxi- mum volume and compliance in sacral spinal cord injury group were significantly less than the control. The DLPP in suprasacral injury group was significantly higher than that in the sacral spinal cord injury group and the con- trol, the DLPP in sacral spinal cord injury group was significantly less than that in the control group. Conclu- sion Urodynamic study is very useful for the early diagnosis and individualized treatment of the neurogenic bladder after spinal cord injury.