Application of mind mapping teaching of gastroenterology in the standardized training for general practitioners / 中华医学教育探索杂志

Objective:To explore the effect of mind mapping teaching of gastroenterology in the standardized training for general practitioners, and provide new ideas for general practice education.Methods:A total of 65 physicians who were enrolled in the standardized training of general practice from January to December 2017 were collected as the control group, and the traditional teaching method was adopted; another 58 physicians from January to December 2018 were selected as the experimental group, and the mind mapping was adopted based on the traditional teaching method. The learning effect (theoretical and operational results) and the satisfaction questionnaire of trainees and teachers were used as evaluation indicators. SPSS 21.0 was used for t test and chi-square test. Results:The theory exam and clinical skills examination results of experimental group (80.80±5.30, 82.66±5.90) were significantly higher than those of the control group (71.60±5.20, 75.72±4.57), and the difference was statistically significant ( P<0.05). Compared with the control group, the experimental group had better understanding of knowledge points of this discipline, clinical thinking ability, higher learning interest, teamwork ability, innovation ability and teacher satisfaction, with statistical significance ( P<0.05). Conclusion:The mind mapping has more advantages than traditional teaching methods in the standardized training for general practitioners, which can be further extended.

Expression and enrichment analysis of HOXC8 in esophageal cancer / 国际肿瘤学杂志

Objective:To investigate the expression of HOXC8 in esophageal cancer and its possible signaling pathway.Methods:The RNA-Seq data of mRNA expression and clinical prognosis data of esophageal cancer dataset were downloaded and preprocessed from the TCGA (The Cancer Genome Atlas) database. The differentially expressed genes were analyzed, and the volcano map and heat map were drawn to visualize the screened differentially expressed genes. The patients with esophageal cancer were divided into high expression group and low expression group based on the median of HOXC8 expression, and survival analysis was performed using Kaplan-Meier method. GSEA 4.0.1 software was used for gene set enrichment analysis, and graphic analysis of multi-GSEA enrichment analysis was performed at the same time.Results:After differential expression analysis of mRNA expression data of 161 esophageal cancer tissues and 11 paracancerous tissues, 3 454 differentially expressed genes were screened, including 2 317 up-regulated genes and 1 137 down-regulated genes. The results of cluster analysis showed that differential expression can effectively distinguish esophageal cancer from adjacent tissues, indicating that the above differential expression results had good accuracy. Difference analysis and paired difference analysis showed that HOXC8 was significantly overexpressed in esophageal cancer, and the differences with tissues adjacent to cancer were statistically significant ( t=5.333, P<0.001; t=3.101, P=0.007). After removing samples with a survival time of less than 30 days, a total of 107 samples were used. The results showed that patients with high expression of HOXC8 ( n=54) had a worse prognosis, with a median survival time of 553 days (95% CI: 396-710), and the median survival time of patients with low expression of HOXC8 ( n=53) was 784 days (95% CI: 62-1 506), with a statistically significant difference ( χ2=4.153, P=0.042), suggesting that HOXC8 was an oncogene. The results of GSEA analysis showed that the samples with high expression of HOXC8 enriched the cell cycle, spliceosome and other related gene sets, while the samples with low expression of HOXC8 enriched the phosphatidylinositol signaling pathway and other related gene sets. Conclusion:HOXC8 is significantly overexpressed in esophageal cancer, and patients with high expression of HOXC8 have a worse prognosis. It may regulate the occurrence and development of esophageal cancer through the involvement of cell cycle, spliceosome, phosphatidylinositol signaling pathway and other signaling pathways.

Construction and analysis of prognostic model for esophageal cancer specific survival rate / 西安交通大学学报(医学版)

Objective To analyze the factors affecting the prognosis of esophageal cancer and construct a reasonable prognostic model. Methods A total of 672 patients diagnosed with esophageal cancer in 2010 were selected as the study data. The factors affecting the specific survival rate of esophageal cancer were screened and modeled by LASSO COX regression analysis. The prediction was performed by R 3.5.3 software. The model was visually constructed and the value of the predictive model was analyzed. Results The 1, 3, and 5 years tumor-specific survival rates of 672 patients with esophageal cancer were 55.32% (95% CI: 51.56% to 59.08%), 30.07% (95% CI: 26.58% to 33.56%), and 25.04% (95% CI: 21.75% to 28.33%), respectively. LASSO regression analysis screened for 11 variables most relevant to prognosis, i.e., chemotherapy, primary site, tumor grade, T stage, N stage, M stage, radiotherapy sequence, surgery, tumor size, age, and ethnicity. Univariate and multivariate COX regression analyses showed that tumor grade, N stage, M stage, surgery and tumor size were independent risk factors for the prognosis of esophageal cancer. By visualizing the prognostic analysis, a Nomogram was constructed, and the consistency index C-index was 0.726 (95% CI: 0.703-0.749), which was significantly better than that of the 7th edition of AJCC's TNM staging system (C-index=0.654, 95% CI: 0.628-0.680). There was also good agreement between the predicted survival rates of the 1, 3 and 5 year calibration curves of this prognostic model and the actual survival rate. At the same time, the ROC curve results showed that if the patient's total score was greater than 15.570, the sensitivity and specificity were the best, the patient could be judged as a high-risk group. And the Nomogram prognostic model constructed in this paper had AUC=0.831, 95% CI: 0.801-0.859, and the prediction ability was significantly better than that of the traditional AJCC 7 version TNM staging system (AUC=0.759, 95% CI: 0.725-0.791). At the same time, a formula for predicting tumor-specific survival rate was constructed: CSS=5.988×10-5×points3+(-1.740×10-3)×points2+(-2.004×10-2)×points+0.685. Conclusion This study used LASSO regression to screen the variables that affected the prognosis of esophageal cancer and visually constructed relevant independent risk factors. It has high clinical value and is of great significance for the screening of high-risk population and the formulation of subsequent personalized diagnosis and treatment plans.

MiR-142-3p enhances chemosensitivity of breast cancer cells and inhibits autophagy by targeting HMGB1

MiR-142-3p has been reported to act as a tumor suppressor in breast cancer. However, the regulatory effect of miR-142-3p on drug resistance of breast cancer cells and its underlying mechanism remain unknown. Here, we found that miR-142-3p was significantly downregulated in the doxorubicin (DOX)-resistant MCF-7 cell line (MCF-7/DOX). MiR-142-3p overexpression increased DOX sensitivity and enhanced DOX-induced apoptosis in breast cancer cells. High-mobility group box 1 (HMGB1) is a direct functional target of miR-142-3p in breast cancer cells and miR-142-3p negatively regulated HMGB1 expression. Moreover, overexpression of HMGB1 dramatically reversed the promotion of apoptosis and inhibition of autophagy mediated by miR-142-3p up-regulation. In conclusion, miR-142-3p overexpression may inhibit autophagy and promote the drug sensitivity of breast cancer cells to DOX by targeting HMGB1. The miR-142-3p/HMGB1 axis might be a novel target to regulate the drug resistance of breast cancer patients.

Lineage reprogramming of fibroblasts into induced cardiac progenitor cells by CRISPR/Cas9-based transcriptional activators

Overexpression of exogenous lineage-determining factors succeeds in directly reprogramming fibroblasts to various cell types. Several studies have reported reprogramming of fibroblasts into induced cardiac progenitor cells (iCPCs). CRISPR/Cas9-mediated gene activation is a potential approach for cellular reprogramming due to its high precision and multiplexing capacity. Here we show lineage reprogramming to iCPCs through a dead Cas9 (dCas9)-based transcription activation system. Targeted and robust activation of endogenous cardiac factors, including GATA4, HAND2, MEF2C and TBX5 (G, H, M and T; GHMT), can reprogram human fibroblasts toward iCPCs. The iCPCs show potentials to differentiate into cardiomyocytes, smooth muscle cells and endothelial cells . Addition of MEIS1 to GHMT induces cell cycle arrest in G2/M and facilitates cardiac reprogramming. Lineage reprogramming of human fibroblasts into iCPCs provides a promising cellular resource for disease modeling, drug discovery and individualized cardiac cell therapy.

Simultaneous Determination of Sodium Valproate and Its Metabolite in Human Plasma by RP-HPLC / 中国药房

OBJECTIVE:To establish a method for simultaneous determination of sodium valproate(VPA)and its metabo-lite 2-propyl-2-pentenoic acid (2-ene-VPA) in human plasma. METHODS:Plasma sample was extracted with cyclohexane and experienced derivatization with 2,4′-dibromoacetophenone using n-octanoic acid as an internal standard. RP-HPLC method was adopted. The determination was performed on Zorbax SB-C18 column with mobile phase consisted of acetonitrile-water(65∶35,V/V)at the flow rate of 1 mL/min. The column temperature was set at 35 ℃,and UV dectection wavelenth was set at 258 nm. The sample size was 20 μL. RESULTS:The linear range of VPA and 2-ene-VPA were 5.0-200.0,0.5-20.0 μg/mL(r=0.999 9, n=5). The limits of quantification were 5.0,0.5 μg/mL. RSDs of inter-day and intra-day were all lower than 5%. Method recov-eries were 95.99%-98.80%and 97.40%-98.17%,and extraction recoveries were 80.46%-86.23%and 80.45%-85.61%. The plas-ma concentrations of VPA in 10 epileptic children were 27.4-93.2 μg/mL,and those of 2-ene-VPA were 0.85-3.94 μg/mL,respec-tively. CONCLUSIONS:The method is simple,specific and suitable for plasma concentration determination and pharmacokinet-ic study of VPA.

Diagnosis and surgical treatment of pulmonary sequestration in adults / 局解手术学杂志

Objective To explore the diagnosis and surgical treatment of pulmonary sequestration in adults. Methods Clinical data of 21 cases of pulmonary sequestration whose diagnosis was confirmed by surgical biopsy in our department from March 2009 to February 2016 were retrospectively analyzed. Divided the patients into the thoracotomy group (n=9) and the thoracoscope group (n=12) according to dif-ferent surgical methods, and compared the diagnosis and surgery of the two groups. Results Among the patients, 8 cases were diagnosed as pulmonary sequestration and the remaining 13 cases were misdiagnosed,with the misdiagnosis rate of 61. 9%. Intraoperative exploration dem-onstrated that the abnormal blood vessels were originated from thoracic aorta (n=14,66. 7%),abdominal aorta (n=4,19%),phrenic artery (n=3,14. 3%) and aortic arch (n=1,4. 8%), and there were 20 cases (95. 2%) of intralobar sequestration and 1 case (4. 8%) of ex-tralobar sequestration. Patients underwent thoracotomy and patients underwent video-assisted thoracoscopic surgery were of no significant differences in operative time (P=0. 104),blood loss (P=0. 209),chest tube duration (P=0. 511),drainage volume (P=0. 135) and postoperative hospital stay (P=0. 450). All the patients recovered well after surgery. Conclusion As pulmonary sequestration lacks specific clinical manifestations,missed diagnosis and misdiagnosis are very common in patients. Chest enhanced CT and CT angiography are effective diagnostic methods at present. Both thoracotomy and VATS can achieve good therapeutic effects.

MicroRNAs and colorectal cancer / 国际肿瘤学杂志

MicroRNAs (miRNAs) are involved in cell growth,differentiation,apoptosis and tumor occurrence and play an important role in regulation.Many studies show that miRNAs can regulate the expression of target gene,which is associated closely with the occurrence,development,chemosensitivity and prognosis of colorectal cancer.Detection of miRNAs is expected to formulate more detailed individualized chemotherapy for colorectal cancer patients and improve their prognosis.

Cytocompatibility of calcium metaphosphate nanoparticles / 中国组织工程研究

BACKGROUND:Calcium metaphosphate has excel ent biocompatibility, degradability, and cel affinity. Human bone marrow mesenchymal stem cel s can grow and proliferate in the pores of the porous calcium metaphosphate, but less is known about calcium metaphosphate nanoparticles. OBJECTIVE:To prepare calcium metaphosphate nanoparticles, and to analyze the effect of calcium metaphosphate nanoparticles at different concentrations on apoptosis of human bone marrow mesenchymal stem cel s by flow cytometry. METHODS:The calcium metaphosphate nanoparticles were prepared by wet bal mil ing. Scanning electron microscopy and transmission electron microscopy were used to observe the morphology of the calcium metaphosphate nanoparticles, and the crystal structure of nanoparticles was analyzed by X-ray diffraction. Calcium metaphosphate nanoparticles were mixed in the CYAGON Oricel TM basal medium, and the concentrations of calcium metaphosphate nanoparticles in the medium were 10, 1, 0.1 mg/L. Human bone marrow mesenchymal stem cel s were cultured for 7 days in the above-mentioned media, and apoptosis of human bone marrow mesenchymal stem cel s was analyzed by flow cytometry. RESULTS AND CONCLUSION:Calcium metaphosphate nanoparticles were successful y prepared by wet bal mil ing, irregular in shape, and the mean diameter was 10-30 nm. X-ray diffraction results showed the crystal structure of nonaparticles was mainlyβ-Ca(PO3)2. The cel ratio of G0/G1 phase and G2/M phase in 10 mg/L group was obviously higher than that in 1, 0.1 mg/L groups (P<0.01). The cel apoptosis rates during the early, middle, late stages in 10 mg/L group were obviously higher than those in 1, 0.1 mg/L groups (P<0.01), and the total cel apoptosis was also significantly increased in 10 mg/L group (P<0.01). These findings indicate that human bone marrow mesenchymal stem cel s proliferation can be inhibited by calcium metaphosphate nanoparticles, and apoptosis rate is increased significantly when the concentration of calcium metaphosphate nanoparticles increases from 1 mg/L to 10 mg/L.

Preparation and cytocompatibility of novel porous calcium metaphosphate composite membranes / 中国组织工程研究

BACKGROUND:Porous poly(3-hydroxybutyrate-co-4-hydroxybutyrate)/calcium metaphosphate composite membranes prepared previously is too thick and uneven in holes. OBJECTIVE:To prepare the thin even porous poly(3-hydroxybutyrate-co-4-hydroxybutyrate)/calcium metaphosphate composite membrane, and to evaluate the cytocompatibility and differentiation capacity. METHODS:Porous and nonporous, thin and even poly(3-hydroxybutyrate-co-4-hydroxybutyrate)/calcium metaphosphate composite membranes were prepared by phase separation method. Its thickness and weight loss rate were determined. Human bone marrow mesenchymal stem cel s were cocultured with porous and nonporous poly(3-hydroxybutyrate-co-4-hydroxybutyrate)/calcium metaphosphate composite membranes for 7 days. Ultrastructure of composite membranes was observed under the scanning electron microscopy. Surface markers of the bone marrow mesenchymal stem cel s on the composite membranes were analyzed using flow cytometry. RESULTS AND CONCLUSION:The thickness of the porous and nonporous composite membranes was (0.041 ± 0.005) mm and (0.058±0.004) mm. Weight loss rates of porous and nonporous composite membranes were respectively 19.93%and 7.64%at 24 hours. Calcium metaphosphate particles were evenly distributed in porous and nonporous composite membrane. Cel s spread entirely, showing spindle shape. Calcium metaphosphate particles were evenly distributed in porous composite membrane. Pore in porous composite membranes was also uniformly distributed, and pore size was about 2-8μm. Cel s spread entirely, showing polygonal shape with multiple tentacles. The tentacles of some cel s entered into the scaffold. CD105, CD90, CD44, CD29 and CD73 expression was detected in porous and nonporous composite membranes. There was no significant difference in cel-positive rate. Poly(3-hydroxybutyrate-co-4-hydroxybutyrate)/calcium metaphosphate composite membranes prepared in this study has good biocompatibility and could not promote cel differentiation.

Expression of glucose-regulated protein 78 in human laryngeal squamous cell carcinoma and its clinical significance / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To investigate the expression of glucose-regulated protein78 (GRP78) in human laryngeal squamous cell carcinoma,and to evaluate its role in the development progress of human laryngeal squamous cell carcinoma.@*METHOD@#The expressions of GRP78 in human laryngeal squamous cell carcinoma, matched pair pericarcinomatous tissue and normal laryngeal squamous epithelial tissue from 90 patients were detected using immunohistochemistry analysis. In addition, the relationship between GRP78 expression and clinical parameters of patients, such as gender, tumor differentiation grade stage, and lymphatic metastasis was analyzed.@*RESULT@#The positive ratio of GRP78 expression in LSCC, matched pair pericarcinomatous tissue and normal laryngeal squamous epithelial tissue were 86.67%, 32.22% and 8.89%. The GRP78 expressions in different tissues were significantly different (P 0.05).@*CONCLUSION@#The expression level of GRP78 protein in human laryngeal squamous cell carcinoma is high and its expression is positively associated with the malignancy of carcinoma. The expression of GRP78 protein participates in the development progress of human laryngeal squamous cell carcinoma.

Modification of seaweed polysaccharide-agarose and its application as skin dressing (III)--skin regeneration with agarose grafting hyaluronic acid sponge / 生物医学工程学杂志

In this paper, a kind of skin dressing, agarose- grafting- hyaluronic acid (Ag-g-HA) sponge was applied to test the modified agarose based scaffold for skin regeneration. The bFGF loading agarose-grafting hyaluronan scaffold had homogenous porosities, and the loaded bFGF was bioactive in 2 weeks. The Ag-g-HA sponge was applied into skin of mice, and it was found that the dressing promoted skin regeneration and no infection and leakage in lesion site took place. H&E staining results showed that the repaired skin was similar to autologous skin. These demonstrate that Ag-g-HA sponge has a promise in skin regeneration.

Bioinformatics analysis and prediction for structure and function of nitric oxide synthase and similar proteins from Plasmodium berghei

OBJECTIVE@#To search and analyze nitric oxide synthase (NOS) and similar proteins from Plasmodium berghei(Pb).@*METHODS@#The structure and function of nitric oxide synthase and similar proteins from Plasmodium berghei were analyzed and predicted by bioinformatics.@*RESULTS@#PbNOS were not available, but nicotinamide adenine dinucleotide 2'-phosphate reduced tetrasodium (NADPH)-cytochrome p450 reductase(CPR) were gained. PbCPR was in the nucleus of Plasmodium berghei, while 134aa-229aa domain was localize in nucleolar organizer. The amino acids sequence of PbCPR had the closest genetic relationship with Plasmodium vivax showing a 73% homology. The tertiary structure of PbCPR displayed the forcep-shape with wings, but no wings existed in the tertiary structure of its' host, Mus musculus(Mm). 137aa-200aa, 201aa-218aa, 220aa-230aa, 232aa-248, 269aa-323aa, 478aa-501aa and 592aa-606aa domains of PbCPR showed no homology with MmCPRs', and all domains were exposed on the surface of the protein.@*CONCLUSIONS@#NOS can't be found in Plasmodium berghei and other Plasmodium species. PbCPR may be a possible resistance site of antimalarial drug, and the targets of antimalarial drug and vaccine. It may be also one of the mechanisms of immune evasion. This study on Plasmodium berghei may be more suitable to Plasmodium vivax. And 137aa-200aa, 201aa-218aa, 220aa-230aa, 232aa-248, 269aa-323aa, 478aa-501aa and 592aa-606aa domains of PbCPR are more ideal targets of antimalarial drug and vaccine.

Bioinformatics analysis for structure and function of CPR of Plasmodium falciparum

OBJECTIVE@#To analyse the structure and function of NADPH-cytochrome p450 reductase (CYPOR or CPR) from Plasmodium falciparum (Pf), and to predict its' drug target and vaccine target.@*METHODS@#The structure, function, drug target and vaccine target of CPR from Plasmodium falciparum were analyzed and predicted by bioinformatics methods.@*RESULTS@#PfCPR, which was older CPR, had close relationship with the CPR from other Plasmodium species, but it was distant from its hosts, such as Homo sapiens and Anopheles. PfCPR was located in the cellular nucleus of Plasmodium falciparum. 335aa-352aa and 591aa - 608aa were inserted the interior side of the nuclear membrane, while 151aa-265aa was located in the nucleolus organizer regions. PfCPR had 40 function sites and 44 protein-protein binding sites in amino acid sequence. The teriary structure of 1aa-700aa was forcep-shaped with wings. 15 segments of PfCPR had no homology with Homo sapien CPR and most were exposed on the surface of the protein. These segments had 25 protein-protein binding sites. While 13 other segments all possessed function sites.@*CONCLUSIONS@#The evolution or genesis of Plasmodium falciparum is earlier than those of Homo sapiens. PfCPR is a possible resistance site of antimalarial drug and may involve immune evasion, which is associated with parasite of sporozoite in hepatocytes. PfCPR is unsuitable as vaccine target, but it has at least 13 ideal drug targets.

Application of seaweed polysaccharide-agarose dressing to animal skin regeneration / 中国组织工程研究

BACKGROUND: It has vedfied that seaweed polysacchande-agarose modifiers have their medical application value. OBJECTIVE: To perform skin regeneration trials using sprayable activated agarose/gelatin solution, and to explore the possibility of egarose modifier as skin dressing for skin regeneration. METHODS: To prepare 3% sprayable mixture with the dissolved activated agarose and gelatin at a certain ratio, and then filtrated with millopore for sterilization to prepare activated agarose (egarose degradation for 8 hours) and gelatin degradation, and made into different ratios (1: 0, 1: 1, 1: 2, 1: 3). A total of four rabbits were obtained, and four sites were selected on the back of each rabbit, totally 16 experimental sites. The sprayable activated agarose/gelatin mixture (1: 1, 1: 2, 1: 3) was directly sprayed on the four lesion sites. Sprayable activated agarose for two sites and simple gelatin for two sites served as controls. The effects of the wounds sprayed with,dressing were observed at 4 weeks following surgery. RESULTS AND CONCLUSION: At 7 days following surgery, the cover film had broken in mixture of activated agarose and gelatin at 1: 3, and remaining three were intact. No infection or inflammation occurred in wound of four ratios. Following comparison, the wound was rapidly healed in 1: 2 ratio dressing. The additional gelatin showed promoting effects on wound healing significantly. Hematoxylin-eosin staining demonstrated that skin with the dressing was similar to autologous skin, which verified that sprayable activated agarose/gelatin have a premise in skin regeneration.

Chondrogenesis of bone marrow mesenchymal stem cells, chondrocytes and adipose-derived adult stromal cells in three-dimensional scaffolds / 中国组织工程研究

BACKGROUND: The key factor for cartilage repair is an orient differentiation of seed cells in three-dimensional scaffold; however,clear cartilage is haply observed in the three-dimensional scaffold.OBJECTIVE: To investigate the chondrogenesis of bone marrow mesenchymal stem cells (BMSCs), chondrocytes (CCs) and adipose-derived adult stromal cells (ADAS) in three-dimensional scaffolds METHODS: BMSCs, CCs, and ADAS were primary-cultured from goat bone marrow following trypsin digestion and amplified in monolayer. P1 BMSCs, P3 CCs, and P3 ADAS were implanted into collagen/hyaluronic acid scaffold at different concentrations of 10%, 20%, 50%, 80%, and 100%, and the cells were then three-dimensionally cultured in serum-free culture media. Two weeks later, SO staining and immunohistochemical staining were employed to observe the synthesis between of chondroitin sulfate and type Ⅱ collagen.RESULTS AND CONCLUSION: The seeded cells had chondrogenesis in scaffolds under certain conditions. In details, BMSCs in 20% (W/W) hyaturonan/collagen Ⅰ scaffolds could perform a hyaline-cartilaginous phenotype when they were expanded with less than 3 passages and cultured in a chondrogenic medium, and CCs did better than BMSCs in chondrogenesis with high passage number; however, ADAS just showed a minor chondrogenesis even in a pellet culture. BMSCs and CCs were better than ADAS as seeded cells for cartilage tissue engineering and regenerative medicine.

Toxicity of Alpha-terthienyl to the Larvae of Aedes albopictus / 中国寄生虫学与寄生虫病杂志

Objective To investigate the toxicity of alpha terthienyl to the larvae of Aedes albopictus , its influencing factors and effect on the larva deve lopment. Methods Under experimental ultraviolet A (UVA),the number of dead,pupal or eclosive mosquito larvae was determined on the condition of different doses of alpha terthienyl and different disposal time in the dark;the number of dead larvae was also determined under sunlight on the condition of different doses of alpha terthienyl and different disposal time to water. Results The LC 50 of alpha terthienyl to Aedes albopictus larvae was 2.37 ?g/L under UVA. The best effect was shown when the larvae were incubated with alpha terthienyl 3 h in dark. Alpha terthienyl could significantly inhibit the larva deve lopment and the emergence of the pupae. Under strong sunlight, the larvae were quickly killed by high concentration alpha terthienyl. The 24 hours effect of alpha terthienyl was better when it was applied at 5 AM than that of at 10 AM and 1PM. Conclusion Alpha terthienyl is an effective, practicable larvicide which prohibits the growth and development of the larvae of Aedes albopictus .

Ultrastructural Dynamic Observation on Murine Schistosomal Hepatic Fibrosis / 中国寄生虫学与寄生虫病杂志

Objective To explore possible mechanisms of hepatic fibrosis by investigating the ultrastructural dynamic changes of liver tissue, especially several kinds of cells related to hepatic fibrosis.. Methods. Murine schistosomal hepatic fibrosis model was established by infecting mice with Schistosoma japonicum cercariae. Routine transmission electron microscopy was used to observe the liver tissue. H.E. staining was used for examining the pathological changes. . Results . H.E. staining showed that the model was established successfully. Ultrastructural observation showed that at the 6th week after infection, the necrosis of hepatocytes around the acute granulomas occurred; the number of sinusoidal endothelial fenestrae and vitamin A droplets in fat-storing cells decreased; large phagosomes and rough endoplasmic reticulum could be seen in the cytoplasm of Kupffer′s cells. At the 8th week, steatosis was found in some hepatocytes, some microvilli emerged on a few inter-hepatocytic surfaces and the inter-hepatocytic spaces were enlarged. Large collagen fibrillar bundles filled in the perisinusoidal spaces, and capillarization of hepatic sinusoids was observed. Secretory vesicles filled with collagen fibrils appeared in the cytoplasm of fat-storing cells with large amount of collagenous fiber bundles surround the cells. Rough endoplasmic reticulum increased in Kupffer′s cells. At the 10th week, fat-storing cells were activated and transformed into myofibroblasts. At the 12th week, the number of myofibroblasts decreased but that of fibroblasts and fiber cells increased. . Conclusion . Activation of fat-storing cells and transformation from fat-storing cells into myofibroblasts are the critical link in the development of hepatic fibrogenesis following schistosome infection. Kupffer′s cells, necrotic hepatocytes and sinusoidal endothelial cells may relate to the activation of fat-storing cells. Capillarization of hepatic sinusoids possibly accelerates the development of hepatic fibrosis.

Aedes albopictus: Cloning and Identification of the Acetylcholinesterase Gene Fragment from the Mosquito / 中国寄生虫学与寄生虫病杂志

Objective To isolate, clone and identify the acetylcholinesterase (AChE) fragment from the mosquito, Aedes albopictus, in relation to exploring mechanism of insecticide resistance. \ Methods\ The genome DNA extracted from the mosquito was used for degenerate polymerase chain reaction (PCR) and the two pairs of oligonucleotides encoding the highly conserved protein sequences were used as primers. The reaction products were cloned to T\|vector and transfected into E^coli JM 109. The replicative form DNA of recombinant vector extracted from E^coli JM 109 through alkalilysis was identified by the methods of digestion with EcoRⅠand SalⅠ and PCR. \ Results\ The products of degenerate primers polymerase chain reaction were obtained and the identified clone belongs to the AChE fragment of the mosquito.\ Conclusion\ The clone was identified as the AChE fragment of Aedes albopictus.