Development and Characterization of A Linear Matrix-assisted Laser Desorption Ionization Mass Spectrometer / 分析化学

Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is an important analytical technique for biological macromolecules,such as proteins,peptides and nucleic acid, especially in the field of microbial identification. Based on previous study,a linear MALDI-TOF MS has been designed and assembled for biological applications. The instrument comprises a vacuum system,a vacuum fast sample introduction system, an optical system, a time-of-flight mass analyzer, an ion source, a data acquisition system and an electric control system. The ion source adopts two-stage source acceleration,delayed extraction and dynamic pulse focusing technology. The time-of-flight distance of field-free drift region is about 1 meter. The optical system adopts a solid laser with adjustable frequency of 1-2000 Hz and spots of 20-100 μm. The angle of incidence laser is controlled at 5 degrees. A series of experiments are carried out to further evaluate the instrument performances. It can not only analyze the samples more than 199 kDa, but also achieve isotope resolution at 1000-3000 Da and up to 900(FWHM) at 5000-17000 Da. The minimum detectable concentration of gramicidin is 10 amol/μL, absolute sensitivity can reach up to 2. 56 amol. Independent detection of saliva samples from different targets shows that the instrument has high reproducibility. We identified Escherichia Coli and Shigella spp,which are two common bacteria but difficult to be differentiated by mass spectrometry,showing its potential identification for clinical microorganism. In a summary,this instrument can play a role on clinical examination in the near future.

Adipose tissue-derived stem cells ameliorates dermal fibrosis in a mouse model of scleroderma

OBJECTIVE@#To investigate the therapeutic potential of adipose-derived stem cells (ADSCs) for limited cutaneous scleroderma (LS) in mouse models.@*METHODS@#ADSCs were isolated from pathogen-free female C57BL/6 mice and LS was induced in wild type (WT) C57BL/6 mice via daily injection of bleomycin (0.1 mL × 300 μg/mL) for 4 weeks; then the ADSCs were subcutaneously injected into the dorsal area in the model treatment group, and 100 μL of phosphate-buffered saline (PBS) solution was injected into the same site in the model control group. Green fluorescent protein (GFP) was used to track the cells using an in vivo imaging system on days 7, 14, 21, and 28 after transplantation. All mice were sacrificed and histologic analyses were performed after 4 weeks, and the skin thickness, collagen deposition and the total content of hydroxyproline were evaluated. Additionally, immunohistochemistry were performed to compare the tissue expression and distribution of TGF-β1 and VEGF between the ADSCs treatment group and the treatment control group.@*RESULTS@#WT C57BL/6 LS mouse model were successfully established and GFP in vivo fluorescence imaging showed that the translated ADSCs survived at the local for at least 4 weeks. Compared with the control group, the ADSCs treatment group significantly attenuated bleomycin-induced dermal fibrosis, reduced the skin thickness and the total content of hydroxyproline (P < 0.05). The ADSCs treatment group displayed significantly lower levels of TGF-β1 and higher levels of VEGF than the control group (P < 0.05).@*CONCLUSIONS@#ADSCs may provide a feasible and practical treatment for autoimmune diseases such as LS and ameliorate dermal fibrosis.

Adipose tissue-derived stem cells ameliorates dermal fibrosis in a mouse model of scleroderma

Objective To investigate the therapeutic potential of adipose-derived stem cells (ADSCs) for limited cutaneous scleroderma (LS) in mouse models. Methods ADSCs were isolated from pathogen-free female C57BL/6 mice and LS was induced in wild type (WT) C57BL/6 mice via daily injection of bleomycin (0.1 mL × 300 μg/mL) for 4 weeks; then the ADSCs were subcutaneously injected into the dorsal area in the model treatment group, and 100 μL of phosphate-buffered saline (PBS) solution was injected into the same site in the model control group. Green fluorescent protein (GFP) was used to track the cells using an in vivo imaging system on days 7, 14, 21, and 28 after transplantation. All mice were sacrificed and histologic analyses were performed after 4 weeks, and the skin thickness, collagen deposition and the total content of hydroxyproline were evaluated. Additionally, immunohistochemistry were performed to compare the tissue expression and distribution of TGF-β1 and VEGF between the ADSCs treatment group and the treatment control group. Results WT C57BL/6 LS mouse model were successfully established and GFP in vivo fluorescence imaging showed that the translated ADSCs survived at the local for at least 4 weeks. Compared with the control group, the ADSCs treatment group significantly attenuated bleomycin-induced dermal fibrosis, reduced the skin thickness and the total content of hydroxyproline (P < 0.05). The ADSCs treatment group displayed significantly lower levels of TGF-β1 and higher levels of VEGF than the control group (P < 0.05). Conclusions ADSCs may provide a feasible and practical treatment for autoimmune diseases such as LS and ameliorate dermal fibrosis.

Case-control study on effect of anterolateral and posterolateral approaches on early postoperative hip abductor strength in total hip arthroplasty / 中国骨伤

<p><b>OBJECTIVE</b>To compare the difference of early postoperative hip abductor strength and function between improved Gibson anterolateral approach (group A) and conventional Gibson posterolateral approach (group B) in patients who had underwent total hip arthroplasty (THA).</p><p><b>METHODS</b>Among 149 patients performing total hip arthroplasty,130 patients were followed up and were randomly divided into two groups (19 unqualified cases were excluded). Group A included 65 cases who underwent anterolateral approach, and the other group included 65 cases who underwent posterolateral approach. In the group A, male:female = 26:39,with an average age of (72.5 ± 8.3) years old, BMI of (24.7 ± 3.7) kg/m², and hip abductor strength of (1.08 ± 0.49) N · m/kg. In the group B, male:female = 30:35, with an average age of (71.6 ± 7.1) years old, BMI of (25.5 ± 3.9) kg/m², and hip abductor strength of (1.05 ± 0.51) N · m/kg. In the age-related control group, male:female = 33:32, with an average age of (73.1 ± 7.5) years old, BMI of (24.2 ± 3.8) kg/m², and hip abductor strength of (1.17 ± 0.53) N · m/kg. The age, BMI, hip abductor strength, anatomy of surgical approach, hip abduction angles and Harris score in all patients were evaluated at the day before surgery and at 1, 2, 3, 6, and 12 months after surgery. All preoperative clinical data (age, BMI and abductor strength of the uninjured side limb ) of these cases had no significant differences.</p><p><b>RESULTS</b>At 1, 2, 3, 6, and 12 months after surgery, the hip abductor strength in group A were (0.53 ± 0.13), (0.66 ± 0.21), (0.85 ± 0.15), (0.95 ± 0.19), (1.03 ± 0.13) N · m/kg respectively, while in group B were (0.46 ± 0.14), (0.57 ± 0.18), (0.78 ± 0.12), (0.85 ± 0.18), (0.98 ± 0.14) N · m/ kg respectively.The differences between the two groups at the 6th months after operation were significant; the hip abduction angles in group A were (25.35 ± 4.31)°, (36.53 ± 5.13)°, (48.07 ± 1.62)°, (61.53 ± 1.77)°, (68.62 ± 3.16)°,while in group B were (23.47 ± 2.41)°, (33.42 ± 4.23)°, (46.64 ± 2.51)°, (60.96 ± 1.75)°, (67.47 ± 4.36)°. The differences between the two groups at the 3rd month after operation were significant. Harris score in the group A were 72.23 ± 2.57, 79.36 ± 3.91, 84.75 ± 3.17, 88.63 ± 2.16, 95.21 ± 1.37 repectively ; while in the group B were 71.58 ± 3.62, 78.96 ± 2.21, 83.97 ± 3.57, 87.92 ± 2.94, 94.83 ± 1.62 respectively. There were no significant differences between them.</p><p><b>CONCLUSION</b>Owing to less muscles interrupted, the THA with improved Gibson anterolateral approach offers a better improvement in earlier hip abductor strength and abduction angle compared with the conventional surgery.</p>

Left ventricular systolic synchrony of patients with hypertensive heart failure but preserved ejection fraction and its impact on left ventricular function / 中华核医学与分子影像杂志

Objective To investigate the systolic synchrony of the left ventricle in patients with left ventricular hypertrophy (LVH) or with heart failure but preserved ejection fraction (HF-PEF),and to evaluate the impact of systolic dyssynchrony on left ventricular function.Methods During June 2011 to May 2014,a total of 352 patients(160 males,192 females,average age:(67.6±7.8)years) with essential hypertension (EH) were enrolled in this retrospective study.Ultrasonic and G-MP1 were performed for assessment of left ventricular remodeling and systolic synchrony and the results were statistically analyzed by oneway analysis of variance and x2 test.Relationship between BNP and synchronic parameters as well as other clinical factors were analyzed by partial correlation analysis.Results The EH patients were divided into hypertension group (rt =182),LVH group (n =74) and HF-PEF group (n =96).In comparison to hypertension group,significant LVH developed in LVH and HF-PEF groups although the LVEF was still preserved.The LVMI of the 3 groups were (94.4±10.1),(121.1±9.8) and (123.2±10.9) g/m2,respectively(F=8.66,P＜0.05).The LVEF was (58.6±7.3)％,(60.8±10.4)％ and (55.1±4.6)％,respectively(F=2.89,P＞0.05).Diastolic dysfunction was identified in LVH and HF-PEF groups with significantly reduced E/A ratio (1.19±0.23,0.80±0.28,0.67±0.17;F=13.46,P＜0.05).Remarkable left ventricular systolic dyssynchrony with phase histogram bandwidth (PHB) of (88.4±8.6) ° and phase standard deviation (PSD) of (23.6±1.9)° and increased BNP of (228.4±69.7) ng/L were revealed in HF-PEF group.The BNP in HF-PEF group was significantly higher than that in LVH group((92.5±13.6) ng/L;q=8.63,P＜0.05).Positive correlation was found between BNP level and PHB,PSD,LVMI,respectively (r=0.277-0.331,all P＜0.05).Conclusion Left ventricular systolic dyssynchrony is concomitant with HF-PEF patients induced by EH,and this dyssynchrony might be one of the factors leading to diastolic dysfunction.

A clinical follow-up study on treatment of adolescent idiopathic scoliosis with brace / 中华外科杂志

<p><b>OBJECTIVE</b>To evaluate clinical outcomes of bracing and analyze related factors that influence curative effects in adolescents with idiopathic scoliosis, and to investigate indications of bracing.</p><p><b>METHODS</b>Seventy-nine patients with AIS who had no history of prior therapy were treated with a brace. Several parameters were consecutive measured and documented during the period of follow-up including Cobb's angles, curve patterns, menarche status, sitting heights, standing heights, Risser sign, apical vertebral rotation, and so on.</p><p><b>RESULTS</b>The average period of followed-up was 30 months (12 months to 60 months). Twenty-one patients (26.6%) presented curve deterioration, 40 patients have no obvious curve change, 18 patients (22.8%) got a curve improvement. There was significantly lower percentage of curve progression and higher percentage of curve improvement in cases with Cobb's angle less than 35 degrees at the first visit (P < 0.05). The percentage of curve progression was significantly greater in the cases with apical vertebral rotation beyond grade III while the percentage of curve improvement was lower (P < 0.05). Curve patterns, Risser sign and other parameters were found to make their effects on the percentage of curve progression and improvement, which, however, was not statistically significant (P > 0.05).</p><p><b>CONCLUSION</b>Bracing can limit or improve mild and moderate curve of idiopathic scoliosis effectively, especially in cases with initial curve magnitude ranging from 20 degrees to 35 degrees . Risser sign is not a reliable parameter for measuring the outcome of bracing treatment for idiopathic scoliosis. Surgery is advised as soon as possible for the cases with initial Cobb's angles greater than 45 degrees and initial apical vertebral rotation beyond grade III early while bracing did not work.</p>

Contribution of blood pressure variability to the effect of nitrendipine on end-organ damage in spontaneously hypertensive rats / 第二军医大学学报

Objective:It has been proposed that blood pressure variability(BPV) is positively related to end-organ damage(EOD) in hypertension.The present work was designed to observe the effects of long-term treatment with nitrendipine and hydralazine on BPV and EOD in spontaneously hypertensive rats(SHR),to examine the hypothesis that lowering BPV with an antihypertensive drug is an important factor in organ protection.Design and methods:Drugs were mixed in rat chow.After 4 months of drug administration,blood pressure was recorded continuously in conscious freely moving rats for 24 h.The heart,kidneys,and brain were then isolated and examined.Results:It was found that nitrendipine significantly decreased blood pressure and BPV,and significantly decreased EOD score in SHR.Hydralazine decreased blood pressure,but did not lower BPV.No effect on EOD was found in hydralazine-treated rats.In control rat(n=38),EOD score was weakly related to systolic blood pressure(r=0.331,P<0.05) and closely related to long-term systolic BPV(r=0.551,P<0.01).In nitrendipine-treated rats,EOD score was closely related to long-term systolic BPV(r=0.602,P<0.01),but not to blood pressure level(r=0.174,P>0.05).Conclusion:BPV plays an important role in the organ-protecting effects of nitrendipine.

Contribution of blood pressure variability to the effect of nitrendipine on end-organ damage in spontaneously hypertensive rats / 第二军医大学学报

Objective:It has been proposed that blood pressure variability(BPV) is positively related to end-organ damage(EOD) in hypertension.The present work was designed to observe the effects of long-term treatment with nitrendipine and hydralazine on BPV and EOD in spontaneously hypertensive rats(SHR),to examine the hypothesis that lowering BPV with an antihypertensive drug is an important factor in organ protection.Design and methods:Drugs were mixed in rat chow.After 4 months of drug administration,blood pressure was recorded continuously in conscious freely moving rats for 24 h.The heart,kidneys,and brain were then isolated and examined.Results:It was found that nitrendipine significantly decreased blood pressure and BPV,and significantly decreased EOD score in SHR.Hydralazine decreased blood pressure,but did not lower BPV.No effect on EOD was found in hydralazine-treated rats.In control rat(n=38),EOD score was weakly related to systolic blood pressure(r=0.331,P<0.05) and closely related to long-term systolic BPV(r=0.551,P<0.01).In nitrendipine-treated rats,EOD score was closely related to long-term systolic BPV(r=0.602,P<0.01),but not to blood pressure level(r=0.174,P>0.05).Conclusion:BPV plays an important role in the organ-protecting effects of nitrendipine.