Objective To discuss the enrichment method of fetal DNA from maternal plasma on size-fractionated separation.Methods Antecubital venous blood (5 ml from each pregnant woman) was collected in EDTA-containing tubes.DNA was extracted from plasma and white blood cells, separately.The DNA was fractionated by agarose gel electrophoresis.Three sections of

Objective To observe the effects of low frequency electromagnetic fields (LFEMFs) on the proliferation of human epidermal stem cells (hESCs) cultured in a three dimensional environment so as to provide an experimental basis for applying LFEMF in skin tissue engineering.Methods hESCs from human prepuces were isolated and purified by the method of rapid adherence to collagen type ⅣV. They were grafted into a type-I collagen sponge or chitosan scaffold in vitro, and then stimulated with different frequencies of LFEMF ( 1 Hz, 10 Hz or 50 Hz) at a magnetic field intensity of 5 mT for 30 min/d. The cells' growth and proliferation were tracked using hematoxylin and eosin (HE) and diamine pheny1 indole (DAPI) staining and observed under the scanning electron microscope at different time points ( on 2nd, 7th, 10th and 14th days of LFEMF intervention). The amounts of cell proliferation at every time point were analyzed and compared.Results LFEMFs of different frequencies showed significantly different efficacy in promoting hESC proliferation. The two scaffolds also showed significantly different effects.By the 10th day, hESCs had grown significantly better on collagen sponge scaffolds than on the chitosan ones. All LFEMF frequencies could promote proliferation of hESCs, but the differences in their effects were statistically significant.Conclusion Collagen sponge may be a preferable scaffold for hESCs cultured in vitro. Rapid proliferation of ESCs in three-dimensional settings can be promoted by LFEMF intervention. LFEMF has relatively great potential in skin tissue engineering.

BACKGROUND:Bone marrow mesenchymal stem cel transplantation is considered as a promising therapy for spinal cord injury. How to more effectively promote the survival of bone marrow mesenchymal stem cel s in the area of spinal cord injury and to accelerate the recovery of motor function after spinal cord injury is a current study focus. Previous studies have found that low-frequency electromagnetic fields can promote bone marrow mesenchymal stem cel proliferation and differentiation, but whether the low-frequency electromagnetic fields can be applied to bone marrow mesenchymal stem cel transplantation for treatment of spinal cord injury requires further studies. OBJECTIVE:To discuss the effects of low-frequency electromagnetic fields on motor function of spinal cord injury rats after transplantation of bone mesenchymal stem cel s. METHODS:Sixty-four rat models of incomplete spinal cord injury at T 10 were established by compression method and then randomized into control group, transplantation group (bone mesenchymal stem cel transplantation), electromagnetic field group and combination group (electromagnetic field+bone mesenchymal stem cel transplantation). After successful modeling, bone mesenchymal stem cel s labeled with 5-bromo-2'-deoxyuridine were injected into the original injured site in the transplantation group and combination group, which were isolated and purified with the fast adherence method;while alpha-minimum essential medium was injected into the electromagnetic field group and control group for instead. At 24 hours post-operation, the electromagnetic field group and combination group were explored to low-frequency electromagnetic fields (frequency 50 Hz, magnetic indaction intensity 5 mT) for 60 minutes per day. RESULTS AND CONCLUSION:After cel transplantation for 21 days, the Basso, Beattie, and Bresnahan scores in the combination group was higher than the other groups (P<0.05). 5-Bromo-2'-deoxyuridine positive cel s grew wel , and integrated into the normal spine;syringomyelia was reduced, and the number of spinal neural cel s was increased in the combination group. In addition, glial fibril ary acidic protein expression was decreased in the combination group, while matrix metal oproteinase 2 expression was increased. It indicates that low-frequency electromagnetic fields could promote recovery of motor function in the spinal cord injury rats transplanted with bone mesenchymal stem cel s, which could be associated that low-frequency electromagnetic fields facilitate the survival of transplanted bone mesenchymal stem cel s, up-regulate the expression of matrix metal oproteinase 2, and reduce glial scar formation in the spinal cord injured site.

Objective To study the polymorphisms of short tandem repeat (STR) loci in intron 1, 24, 13 and 22 (STR 1,24, 13, 22) of factor Ⅷ (FⅧ) gene in Chinese population, and establish single tube multiple fluorescent PCR method for rapid diagnosis of haemophilina A(HA). Methods Four STRs from genomie DNA of 220 females without blood relationship were amplified in a single tube using quadri-fluorescence PCR. Capillary electrophoresis was analyzed in ABI PRISM 310 Genetic Analyzer. DNA sequencing was used to assay the number of dinueleotide repeats. Gene diagnosis were performed in 96 HA families. Results It was observed that 7, 9, 10 and 7 different alleles were found in STR1, 24, 13 and 22, respectively. The PIC (polymorphism information contents) were 0. 3789, 0. 4055, 0. 5239 and 0. 4713 in STR1,24, 13 and 22, respectively, and the HR (heterozygesity rate) were 34. 55% (76/220), 38. 18% (84/220), 49. 55% (109/220) and 43.64% (96/220). In 96 HA families, the diagnosis rate of STR1, 24, 13 and 22 were 38. 54% (37/96), 38. 54% (37/96), 54. 17% (52/96), 42. 71% (41/96), respectively. Whereas it achieved 79. 17% (76/96) when combining the four STR markers. Conciusion The single tube multiple fluorescent PCR of four STR loci is an effective, simple, quick method for linkage analysis and gene diagnosis of haemophilia A.

Objective To test whether multiplex ligation-dependent probe amplification(MLPA)could be used for the prenatal detection of the most common aneuploidies of chromosomes 13,18,21,X,and Y.Methods 34 cases including 22 blood samples(12 with trisomy 21,1 with monosomy X,one male witll extra Y and 8 healthy persons),4 cord blood samples with Down syndrome and 8 amniotic fluid samples ( 1 with trisomy 21 and 7 normal fetuses)were recruited into this study.All samples were confirmed by karvotype analysis. DNA was extracted from blood and amniotic lysate was incubated with proteinase K.MLPA was used to determine the relative copy numbers.Results The resuhs were available within 48 h and were concordant with karyotype analysis in all but one case of amniotic fluid that was suggested to be triploid sample 69,XXY by MLPA or contaminated by maternal blood.This sample actually was found containing a number of red blood cells after centfifugation in test. In total,the concordance rate with clinical characteristics was 97.1%.The Ratio values of 13,18,21,X in normal samples were approaching 1.0 except chromosome Y having slightly higher variation in relative copy number.The difference of ratio means between the normal and trisomy 21 samples was statistically significant by one-way ANOVA(F=298.906.P=0.000).Conclusion Computer assisted MLPA with high sensitivity is a rapid,simple,automatic and reliable method for detection of common chromosomal aneuploidies.

Objective To study the effect of electrical stimulation breath training on lung function of patients following pulmonary lobectomy. Methods 62 patients following pulmonary lobectomy were randomly allocated into experimental group (n=30 )and control group (n=32). The experimental group received a 4-week supervised electrical stimulation breath training program using an electric stimulus feedback trainer (20mins per time, 3 times per week);The control group received postoperative routine nursing. Cadiopulmonary function evaluation of 2 groups were tested before and after the experiment. The evaluation included the 6-min walking test (6MWD), FVC, FEV1,W,AT and VO2max/kg. Results After 4 week training, the value of 6MWD,W,FVC,FEV1 all improved, compared to the baseline value (P < 0.05) and the value of 6MWD,W,FVC,FEV1 were more obvious in experimental group, compared to control group(P<0.05). The AT value and the VO2max/kg value increased than the baseline value (P<0.05)and the improvement degree was more remarkable in experimental group than that in control group (P<0.05). Conclusion Electrical stimulation breath training can improve cardiopulmonary function of the patients following pulmonary lobectomy.

Objective To analyze the correlation of inflammatory markers C-reactive proten(CRP),serum amyloid protein A(SAA),interleukin-6(IL-6)levels and subjective sleep characteristics in patients with first-episode acute cerebral infarction.Methods A total of 113 patients with first-episode cerebral infarction admitted to the Department of Neurology,the People's Hospital of Fuyang from March 2022 to April 2023 were prospectively and continuously selected as subjects.According to the Pittsburgh sleep quality index(PSQI),they were divided into insomnia group(PSQI＞7 points)and non-insomnia group(PSQI ≤7 points).General demo-graphic data and differences in CRP,SAA,IL-6 levels,Hamilton anxiety scale(HAMA)and Hamilton depression scale(HAMD)scores were compared between the two groups.Partial correlation analysis was used to analyze the correlation between three serum markers and PSQI effect factors.Results There were no significant differences in age,gender,baseline NIHSS score and mRS score between the two groups(P＞0.05).HAMD scores(z=-3.993,P＜0.001),HAMA scores(z=-3.806,P＜0.001),CRP,IL-6,SAA(P＜0.001)in insomnia group were significantly higher than those in non-insomnia group.The history of hyperlipidemia between the two groups was statistically significant(z=5.913,P=0.015).Multivariate Logisitic regression analysis showed that CRP(OR=1.55,P＜0.01),HAMD scores,HAMA scores and hyperlipidemia were independent risk factors for chronic insomnia in patients with first-episode cerebral infarction,and HAMD scores had a greater effect than HAMA scores(OR:1.10 vs 1.04).Partial correlation analysis showed that IL-6 and CRP levels were significantly correlated with the total score of PSQI(P＜0.05),while SAA was not significantly correla-ted with the total score of PSQI(P＞0.05).IL-6 level was positively correlated with sleep quality(r=0.231)sleep efficiency(r=0.322)and sleep duration(r=0.221).SAA level was positively correlated with sleep efficiency(r=0.242),while CRP level was posi-tively correlated with sleep latency(r=0.194),sleep duration(r=0.247)and sleep efficiency(r=0.225).Conclusion The inflam-matory markers CRP,IL-6 and SAA levels were elevated in the patients with first-episode cerebral infarction accompanied by insomnia,which were correlated with the severity of insomnia.The correlation between CRP and IL-6 levels and sleep characteristics was consistent with each other.

BACKGROUND:The repair and management of ful-thickness skin defects resulting from burns and chronic wounds remain a significant unmet clinical chal enge. Using epidermal stem cel s and keratinocyte growth factor for ful-thickness wound repair is a promising approach. Low-frequency electromagnetic fields which are a non-invasive physical stimulation therapy have been recognized as a good method to enhance wound healing. OBJECTIVE:To develop a new strategy to accelerate wound healing by transplanting transfected epidermal stem cel s and keratinocyte growth factor and treating with low-frequency electromagnetic fields in a mouse model. METHODS:Epidermal stem cel s from Sprague-Dawley neonatal rats were isolated and cultured in vitro, then the cel s were labeled with 5-bromo-2-deoxyuridine and transfected by Ad-KGF, a recombinant adenovirus carrying the keratinocyte growth factor. Mice were given to create ful thickness skin wound on the dorsum and randomly assigned to four groups:control group, transplantation of epidermal stem cel s group, transplantation of keratinocyte growth factor gene modified epidermal stem cel s group, and transplantation of keratinocyte growth factor gene modified epidermal stem cel s plus low-frequency electromagnetic field exposure group. RESULTS AND CONCLUSION:The best healing pattern was observed in the keratinocyte growth factor gene modified epidermal stem cel s plus low-frequency electromagnetic field exposure group (P<0.05) at days 9 and 16. 5-Bromo-2-deoxyuridine labeled cel s existed in the wound in the treated groups at day 9. A significantly increased expression of endogenous keratinocyte growth factor was detected in the transplantation of Keratinocyte Growth Factor gene modified epidermal stem cel s group, and transplantation of keratinocyte growth factor gene modified epidermal stem cel s plus low-frequency electromagnetic field exposure group at day 16. A wel-advanced epithelialization was observed in transplantation of keratinocyte growth factor gene modified epidermal stem cel s plus low-frequency electromagnetic field exposure group at days 16 and 30. These results suggest that low-frequency electromagnetic fields enhanced wound healing fol owing the transplantation of keratinocyte growth factor gene modified epidermal stem cel s.

Objective To analysis the correlation between the vulnerability of carotid plaque and ischemic stroke and to explore the clinical significance of assessing vulnerable plaques accurately.Methods A total of 64 patients,who underwent carotid endarterectomy (CEA) in First Affiliated Hospital of Soochow University from October 2014 to February 2016,were classified into ischemic and non-ischemic stroke group according to whether ischemic stroke symptoms occurred during the last 6 months before surgery.To judge the stable and vulnerable plaques,the patients underwent carotid doppler ultrasonography (CDU) before surgery,and the carotid plaques were evaluated with HE staining after CEA.We also analyzed the risk factors of plaque formation and the relevance between the plaque characteristic and ischemic stroke with chi-square test.Kappa test were used to analyze the consistency of CDU and pathology.Results Of the 44 cases in ischemic stroke group,CDU identified 81.8％ (36/44) vulnerable plaques and 18.2％ (8/44) stable plaques,while pathology confirmed 86.4％ (38/44) vulnerable plaques and 13.6％ (6/44) stable plaques.Of the 20 cases in non-ischemic stroke group,CDU identified 35％ (7/20) vulnerable plaques and 65％ (13/20) stable plaques,while pathology confirmed 40％ (8/20) vulnerable plaques and 60％ (12/20) stable plaques.In both CDU and pathology,vulnerable plaques in ischemic stroke group were obviously higher than that in non-ischemia group (x2=13.67,P ＜ 0.001;x2=14.62,P ＜ 0.001).The results of CDU agreed well to that of pathology results (Kappa=0.669,P ＜ 0.01).Conclusions The vulnerability of plaques were closely related to the ischemic stroke.CDU is a reliable examination method to identify vulnerable plaques.The accurate assessment of vulnerability of plaques has a great significance in preventing ischemic stroke.

Objective:To evaluate the efficacy and safety of rituximab(RTX) as remission-mainten-ance therapy in antineutrophil cytoplasmic antibody(ANCA) associated vasculitis(AAV).Methods:Patients with AAV, including granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA), treated with rituximab (RTX) in Peking Union Medical College Hospital during September 2005 to June 2021 were included into this study. Clinical data, relapse rate, time of first relapse and adverse events were collected and analyzed. The cumulative relapse rate was calculated by Kaplan-Meier, t test, and Man-Whithey U test and chi-square were used to compare differences between two groups. Results:① Thirty-nine AAV patients were enrolled, including 36 GPA and 3 MPA. During the 20(3, 104) months follow-up, 59.0%(23/39) patients had suffered relapses. The time for first relapse was 11(3, 42) months after remission. ② There were no difference in the relapse rate [60.0%(18/30) vs 55.6%(5/9), χ2=0.06, P=1.000), the time of first relapse [15(3, 42) vs 10(9, 30), Z=0.45, P=0.678], CD19 + B [23.5 (5, 148) cell/μl vs 3(2, 15) cell/μl, Z=0.57, P=0.605] and serum IgG [7.09(5.13, 13.90) g/L vs 9.72(5.32, 12.0) g/L, Z=0.36, P=0.770] between standard dose and low-dose groups. The rate of major relapse-free was significantly less in patients treated with standard dose than patients with reduced dose of RTX {87.1%[95% CI(73.4%, 100.8R%)] vs 64.3%[95% CI(23.1%, 105.4%)], χ2=7.59, P=0.006}. ③ There were no difference in relapse rate [50.0%(3/6) vs 60.6%(20/33), χ2=0.24, P=0.674], time of first relapse [23(6, 25) vs 11(3, 42), Z=0.05, P=0.982], CD19 + B[35(15, 50) cell/μl vs 10(0, 148) cell/μl, Z=0.95, P=0.382] and serum IgG[6.70(5.91, 7.49) g/L vs 7.69(3.78, 13.90) g/L, Z=0.48, P=0.700] between the fixed interval dosage and the on-demand dosage groups. There was no difference in the rate of major relapse-free between the two groups (100% vs 77.8%, χ2=1.79, P=0.181). ④ The incidence of infusion reaction was 5.1%(2/39) and infection was 20.5%(8/39). Serum IgG level was 4.37(3.78, 13.4) g/L at infection. There was no difference in safety between the standard and low-dose groups or between fixed interval and on-demand dosage groups ( P>0.05). Conclusion:There is no significant difference in relapse rate bet-ween the standard RTX dose and low-dose RTX induction therapy group, but the major relapse rate is sign-ificantly reduced in the standard dose RTX therapy. The relapse rate of fixed intervals dosage group is similar to that of on-demand dosage group. The safety profile of the standard dose and low-dose induction therapy groups or fixed intervals and on-demand dosage groups is similiar.