Research progress of neoadjuvant therapy for locally advanced rectal cancer / 中华胃肠外科杂志

The clinical application of novel chemotherapeutic drugs including oral 5-FU and targeted drugs and preoperatively accurate imaging grading has brought challenges to the indication criteria developed by NCCN and ESMO for neoadjuvant chemoradiotherapy in locally advanced rectal cancer (LARC). Extended hotspots have focused on the effectiveness of using capecitabine instead of fluorouracil infusion, the combination of multiple drugs and the feasibility of using neoadjuvant chemotherapy instead of neoadjuvant chemoradiotherapy for selective patients. Traditionally, the evaluation of the effect of neoadjuvant therapy has been based on the effect on the pathological complete remission (pCR) rate. However, current studies recommend the disease-free survival (DFS) as a more important outcome. Besides, seeking for effective biomarkers as predictive markers for neoadjuvant therapies or as prognostic markers remains a hotspot in the field of neoadjuvant chemoradiotherapy. The "watch and wait" approach refers to taking a close follow-up strategy instead of direct operation for patients achieving clinically complete remission (cCR) after neoadjuvant therapy. However, there is no unified evaluation criteria and time point for the evaluation of cCR following neoadjuvant therapy. Therefore, there remain a lot of controversies regarding the clinical application of neoadjuvant chemoradiotherapy in LARC. In this manuscript, research progress in the indication for neoadjuvant therapy, improvement in the neoadjuvant therapeutic schedule, advancement of the efficacy evaluation criteria of neoadjuvant therapy, the "watch and wait" approach and other hot topics is summarized to provide references for clinical practice.

Primary investigation of immediate oral feedback in objective structure clinical examination / 中华医学教育探索杂志

Objective To investigate the immediate oral feedback after objective structure clinical examination (OSCE) for postgraduate year 1 & 2 surgery residents (PGY1 & 2).Methods 37 PGY1 and 38 PGY2 wereevaluated.The examination was composed of 6 stationsand limited to15 minutes per station.Each station was evaluated by centesimal system score.Immediate oral feedback was given in the last2 minutes.A questionnaire was given to each resident and examiner at the end of OSCE.All data analyses were conducted using SPSS version 22.0,repeated measures ANOVA and LSD test were used,and correlations were tested by the Pearson correlation test.Results The average scores for PGY1 & 2 were (68.97 ± 5.40) and (68.35 ± 5.00),the between-and inter-round differences in average score were not statistically significant.There was no significant correlation about theevaluation of the residents' performance during OSCE between the examiners and the residents.The necessity and effectiveness of immediate oral feedback were confirmed by both the examiners and the residents.Conclusions Immediate oral feedback isfeasible with limited impact on OSCE score,but the plan should be furtherrefined.Follow-up study isnecessary to identify the long-term effect on the clinical competency.

Research progress on relationship between bile acids and intestinal mucosal mechanical barrier function / 中华消化外科杂志

Intestinal mucosal mechanical barrier is one of the most important structure to maintain the body homeostasis.The occurrences of inflammatory bowel disease,necrotizing enterocolitis and poor prognosis of patients with obstructive jaundice are closely related to the damage of the mucosal barrier function.Long-term high fat diet and obstructive jaundice can cause the abnormality of bile acids metabolism.These pathological conditions are often associated with the destruction of intestinal mucosal barrier function.So the correlations between abnormal bile metabolism and intestinal mucosal mechanical barrier function have aroused interests of many researchers.They found that bile acids the important component of bile are closely related to the intestinal barrier function.The paper reviewed the recent articles and summarized the mechanisms of the deficiency of bile acids,excessive bile acids and abnormal bile acids composition damaging the intestinal mucosal barrier function.It will provide reference for the new fields of study,prevention of the toxic effects of bile acids and the improvement of the prognosis of patients.

Progress of molecular subtypes of colorectal cancer / 中华肿瘤杂志

Colorectal cancer is one of the leading causes of morbidity and mortality around the world. Although the staging and classification systems, such as tumor/node/metastasis (TNM) staging, are widely used in clinic, there are some limitations. For example, the patients with the same pathological type, TNM stage and treatment regimen show a completely different prognosis and outcome. In the present, molecular subtyping was concerned for a more precise and accurate staging of colorectal cancer. Herein, we reviewed the literature of the molecular subtypes of colorectal cancer in the past decades. The clinical significance of various molecular subtyping systems was evaluated and compared. It will provide reference for the precision medicine of colorectal cancer in the future.

Retrospective Study on the Protocol Deviation in Drug Clinical Trial Implementation of Our Hospital / 中国药房

OBJECTIVE:To study the influencing factors of protocol deviation in drug clinical trial implementation,and pro-vide reference for improving the quality of drug clinical trial. METHODS:Quality verification was conducted for the drug clinical trial projects in the First Affiliated Hospital of Chongqing Medical University during 2010-2016,and protocol deviations in each year were retrospectively studied,classified and analyzed. Category,frequency,international and domestic pilot projects and the differences of protocol deviation after full-time research nurse participating in trail management were explored,and the measures were put forward. RESULTS:27 drug clinical trials were implemented in our hospital during 2010-2016,including 949 cases,176 cases with protocol deviation,accounting for 18.55％. Deviation protocol in drug clinical trial was decreased year by year for 7 years. The categories were mainly incompleteness of observation/records (30.11％),checking omission/broaden the window(28.41％),adverse drug events and improper combined medication (14.20％) and omission in drug management (11.93％). The proportion of protocol deviation with full-time research nurse participated was lower than the projects without full-time research nurse(11.11％ vs. 28.67％,P<0.01),and proportion of deviation protocol in international multi-center project was lower than the domestic projects(6.60％ vs. 28.84％,P<0.01). CONCLUSIONS:It is suggested to pointedly strengthen the weak links of drug clinical trial. For example,clinical trial institutions should establish the clinical trial data retention system,electronic data should be timely backed up in a different places,etc. Besides,clinical trial institutions should equip professional full-time research nurses as much as possible,learn the rigorous scientific experimental design,standard operational procedures and the authenticity of data pro-cessing from the international multi-center clinical trial projects to effectively reduce the incidence of deviation protocol and im-prove the quality of drug clinical trials.

Research progress of the association of hydrogen sulfide with colorectal cancer and its associated anti-tumor drugs / 中华胃肠外科杂志

As the third confirmed gaseous transmitters, hydrogen sulfide was found to play a vital role in the eternal milieu both physiologically and pathologically. What's intriguing is that, there exists a debate about the role of hydrogen sulfide in the pathogenesis of cancer, especially colorectal cancer. In this manuscript, progress of the effect of low and high dose hydrogen sulfide on the tumorigenesis of colorectal cancer and research on the antitumor new drugs stemmed from the function of hydrogen sulfide is summarized. Recently, the "bell-shape" model of the action of hydrogen sulfide illustrated that hydrogen sulfide was able to promote the progression of tumor in low dose and inhibit the progression of tumor in high dose. Based on these results, both hydrogen sulfide synthesis inhibitors and hydrogen sulfide donors(chimeras with NSAIDs) have been widely studied as potential anti-tumor novel drugs. According to the actual results of present studies, hydrogen sulfide synthesis inhibitors featured by aminooxyacetic acid (AOA) is more promising as a novel kind of drug. The future research based on the relationship between hydrogen sulfide and rectal cancer may bring insights into the development of novel anti-tumor drugs, thus producing tremendous potential clinical value.

Research progress on risk factors associated with postoperative recurrence in patients with Crohn's disease after bowel resection / 中华胃肠外科杂志

Emergency and complications make bowel resection necessary for patients who suffer from Crohn's diseaes (CD) which is traditionally treated mainly by medical therapy. CD patients can obtain temporary relief after bowel resection. However, the high recurrence rate after surgery tends to result in repeated operations. Preoperative factors, the details of the surgery and postoperative medical treatment are considered to be related to postoperative recurrence. In this manuscript, progress on risk factors associated with postoperative recurrence in patients with Crohn's disease after bowel resection is summarized.

Molecular typing and resistance mechanisms of carbapenem resistant Pseudomonas aeruginosa isolated from a Chinese surgical intensive care unit / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Carbapenems are an important class of drugs for the treatment of Pseudomonas aeruginosa (P. aeruginosa) infections. However, carbapenem resistance has been commonly observed in nonfermenter species of bacteria. The purpose of this study was to investigate the molecular epidemiology and carbapenem resistant mechanisms of P. aeruginosa isolated from a surgical intensive care unit (SICU) in China.</p><p><b>METHODS</b>The molecular typing was analyzed by REP-PCR. Enzyme activity was measured with a 260 nm wavelength spectrophotometer. The levels of outer membrane proteins OprD and OprN were measured by Western blotting. The levels of mexA gene transcriptional expression were measured by quantitative real-time PCR. The metallo-beta-lactamase genes IMP, VIM, SPM, GES, and GIM were amplified by PCR. DNA fragments were sequenced by an automated ABI PRISM 3700.</p><p><b>RESULTS</b>Forty-two strains resistant to carbapenems isolated from a SICU were analyzed. REP-PCR revealed 34 belonging to type A, a predominant strain in this SICU. But we did not find metallo-beta-lactamases IMP, VIM, SPM, GES, or GIM genes by PCR. With a three-dimensional extract test, we found 34 strains producing high levels of AmpC enzymes. We also observed the activity of beta-lactamases enzymes in the imipenem resistant group, which was statistically different from the sensitive group. Western blotting revealed that 23 strains showed loss of OprD, 18 strains had decreased OprD expression, and 14 strains expressed OprN. We discovered 27 strains that overexpressed mexA by quantitative real-time PCR, and the resistance rate to meropenem was statistically different between the overexpressing group and the low-expressing group. Nucleotide sequences and deduced amino acid sequence analysis revealed that eight strains carried mutations in the mexR gene operon down regulating MexAB-OprM. The nucleotide sequences of mexR genes from PA36, PA41 and PA48 were submitted to the Genebank with accession numbers of AY899299, AY899300, and AY899301.</p><p><b>CONCLUSIONS</b>There was a predominant strain in the SICU of our hospital. Imipenem resistance is mainly mediated by OprD deficiency or loss, and high activity AmpC enzymes. Overexpression of MexAB-OprM is one of the mechanisms of meropenem resistance, which are partly upregulated by mutations in the mexR gene. The expression of MexEF-OprN also plays an important role in the carbapenem resistance.</p>

Research on influence of intravenous infusion by double-lumen PICC on continuous dynamic CVP monitoring / 重庆医学

Objective To investigate the influence of intravenous infusion by double-lumen peripherally inserted central catheter (PICC)on continuous dynamic central venous pressure(CVP)monitoring.Methods In the patient undergoing the double-lemon PICC,continuous dynamic CVP monitoring was performed by a lumen and the intravenous infusion was conducted by another lu-men.Whether the simultaneous venous infusion affecting the values of continuous dynamic CVP monitoring was observed.Results Intravenous infusion through double-lumen PICC had no influence on simultaneously continuous dynamic CVP monitoring (P>0.05),which could influence the values of CVP monitoring when simultaneously using the intravenous infusion pump(P0.05).The CVP values could recovered to the status before infusion when continuously infusing after stopping using the infusion pump.Compared with before in-fusion,the CVP values after stopping intravenous infusion had no obvious change(P>0.05).Conclusion Intravenous infusion by double-lumen PICC has no influence on continuous dynamic CVP monitoring.But simultaneously adding infusion pump has certain influence on the CVP monitoring values.

Role of paxillin in colorectal carcinoma and its relationship to clinicopathological features / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Colorectal carcinoma is one of the most common malignant tumors. Despite advances in therapy, mortality is still very high. The aim of this study was to evaluate the expression of paxillin in the human colon adenocarcinoma cell line SW480 and its role in cell cycle and apoptosis. We also investigated the expression of paxillin in colorectal carcinoma tissues and its relationship to clinicopathological features and survival.</p><p><b>METHODS</b>Paxillin short hairpin RNA (shRNA) was constructed and transfected into the colon adenocarcinoma cell line SW480. The influence of paxillin shRNA on the cell cycle and cell apoptosis was analyzed by flow cytometry. Immunohistochemistry staining was used to assess the expression of paxillin and its association with the expression of carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 19-9, p53 and Bcl-2 in 102 patients with primary colorectal carcinoma. Western blotting was also used to investigate the expression of paxillin. Medical records were reviewed and a clinicopathological analysis was performed.</p><p><b>RESULTS</b>In vitro, the percentage of cells in S phase was (45.23±1.05)%, (43.53±1.23)%, and (36.13±0.57)% in the blank control group, negative control group, and paxillin shRNA group respectively. It was significantly decreased in the paxillin shRNA group (P = 0.000). The early apoptosis index of the paxillin shRNA group (17.2±1.18%) was significantly increased compared to the control shRNA group ((13.17±1.15)%, P = 0.013). Paxillin was positive in 71 (69.6%) patients, and it was found to be overexpressed in tumor tissues compared with normal adjacent tissues. Paxillin positive rate was higher in patients who are less than 50-years old (100.0% vs. 65.6%, P = 0.016). Paxillin expression was associated with a high histologic grade of carcinoma (81.4% vs. 61.0%, P = 0.031), a high rate of regional lymph node metastasis (22.5% vs. 13.0%, P = 0.031), mesenteric artery lymph node metastasis (100.0% vs. 64.8%, P = 0.008), distant metastasis (94.1% vs. 64.7%, P = 0.016) and a high Tumor Node Metastasis (TNM) stage (94.1%, 73.2%, 60.0%, and 50%, P = 0.030). Multivariate analyses revealed that recurrence was associated with the rate of regional lymph node metastasis (P = 0.001) and paxillin expression (P = 0.024). Multivariate analysis indicated that the overall survival is related to the TNM stage (P = 0.000).</p><p><b>CONCLUSIONS</b>In vitro, paxillin may promote cell proliferation and inhibit apoptosis in SW480 cells. Paxillin may be a potential metastasis predictor, and an independent prognosis factor of recurrence. It may also be related to poor patient outcomes, but was not an independent predictor of survival.</p>

Surgical treatment and prognosis analysis of cT4bM0 primary rectal cancer / 中华消化外科杂志

Objective To investigate the surgical treatment strategies and prognostic factors of cT4bM0 primary rectal cancer.Methods The clinical data of 53 patients with cT4bM0 primary rectal cancer who were admitted to the First Hospital of Peking University from January 2000 to December 2010 were retrospectively analyzed.All the patients received en-bloc multivisceral resection and postoperative chemotherapy.The survival and prognostic factors were analyzed.The patients were followed up via out-patient examination,phone call or mail,and the follow-up was ended till December 2012.The survival curve was drawn using the Kaplan-Meier method,and the survival was analyzed using the Log-rank test.Uni-and multivariate analysis were done using chisquare test and COX's proportional hazard model.Results Of all the 53 patients,20 received posterior pelvic exenteration (PPE),20 received total pelvic exenteration (TPE),3 received low anterior resection (LAR) +local resection of ballder,2 received LAR + ovariectomy,2 received LAR + local resection of ureter,1 received LAR + local resection of posterior vaginal wall,1 received LAR + vesiculectomy and vesectomy,3 received abdominoperineal resection (APR) + local resection of posterior vaginal wall,1 received APR + sacrectomy.R0 resection was achieved in all the patients.No intraoperative death was observed,and the incidence of postoperative complication was 9.4％ (5/53).The results of postoperative pathological examination showed that 2 patients were with well-differentiated adenocarcinoma,41 with moderate-differentiated adenocarcinoma,and 10 with poorly differentiated adenocarcinoma.Twenty-four patients were with lymph node metastasis.Four patients were in TNM stage Ⅰ,25 in TNM stage Ⅱ and 24 in TNM stage Ⅲ.Fifty-three patients were followed up postoperatively,and the median time for follow-up was 33 months (range,4-116 months).The overall 5-year survival rates was 57.3％.The 5-year survival rate for patients with or without lymph node metastasis were 77.1％ and 30.4％,respectively,with significant difference between the 2 groups (x2 =7.374,P ＜ 0.05).The 5-year survival rates of patients with malignant infiltration and inflammatory adhesion mere 51.0％ and 68.5％,with no significant difference (x2=1.148,P ＞0.05).The 5-year survival rates of patients with malignant infiltration and inflammatory adhesion in stage Ⅱ were 74.6％ and 85.7％,with no significant difference between the 2 groups (x2=0.118,P ＞ 0.05).The 5-year survival rates of patients with malignant infiltration and inflammatory adhesion in stage Ⅲ were 28.8％ and 37.5％,with no significant difference between the 2 groups (x2 =0.959,P ＞ 0.05).The results of univariate analysis showed that lymph node metastasis and TNM stage were the risk factors influencing the prognosis of patients with cT4bM0 primary rectal cancer (x2=6.468,6.596,P ＜ 0.05).The results of multivariate analysis showed that lymph node metastasis was the independent risk factor (RR =3.797,P ＜ 0.05).Conclusions En-bloc multivisceral resection should be the first surgical treatment choice for patients with cT4bM0 primary rectal cancer,and lymph node metastasis is the independent risk factor.Under the same N stage,the prognosis of patients with malignant infiltration or inflammatory adhesion is similar if R0 resection is achieved.

Lymph node metastasis around the root of inferior mesenteric artery in rectal cancer / 中华普通外科杂志

Objective To investigate factors affecting the metastasis of lymph nodes around the root of inferior mesenteric artery(IMA) in rectal cancer,and the significance of root lymph nodes dissection of IMA in radical surgery for rectal cancer.Methods Clinicopathological data of 105 rectal cancer patients undergoing root lymph node dissection of IMA during radical resection in Peking University First Hospital from January 2005 to December 2008 were analyzed retrospectively.Rectal cancer patients without root lymph node dissection of IMA during the same period served as control.Results were compared between these two groups for survival and local recurrence rates.Results The rate of lymph node metastasis around the origin of IMA was 9.5％ (10/105).The five-year survival rate in patients with IMA root nodal dissection was 71.3％,and that without was 70.6％ (P =0.995),while the local recurrence was respectively 1.9％ and 7.4％ (P ＜ 0.05).In multivariate analyses,IMA root nodal metastasis occurred more frequently in patients with pT3 and pT4 tumor(Wald =5.764,P ＜ 0.05) and poorly differentiated tumor(Wald =7.818,P ＜ 0.05).Conclusions Root lymph nodes dissection of IMA could not increase five-year survival rate,but it could reduce local recurrence rate in patients with rectal cancer.In radical surgery of rectal cancer,lymphadenectomy of IMA root should be performed in patients with T3 and T4 tumor with poorly differentiated tumor,so as to reduce local recurrence rate.

Surgical resection of primary retroperitoneal schwannoma / 中华普通外科杂志

ObjectiveTo explore the clinical diagnosis and surgical treatment of primary retroperitonealneurilemoma(schwannoma). MethodsClinicaldataof 47patientsof primary retroperitoneal schwannoma admitted and surgically treated from January 1995 to December 2009 were retrospectivelly reviewed.ResultsAs diagnosed by pathology there were 36 cases of Benign schwannoma,with a median age at onset of 41years, among those 11 patients were symptomatic, and 25 were asymptomatic. There were 11 malignant 11 cases, the median age was 38 years, among those 6 patients were symptomatic, and 5 were asymptomatic. The positive diagnostic rate of preoperative CT and MRI were 36. 2％ ( 17/47 ) and 58. 3％ ( 7/12 ) respectively. Immunohistochemically positive rates of S-100 were 100％ and 81.8％(9/11) in benign and malignant group respectively.All cases underwent surgical treatment. Surgical resection rates for benign and malignant groups were 100％ and 90. 9％(10/11)respectively. There was no perioperative death, Overall 5-year survival rates were 100％ and 45.5％ for benign and malignant tumors groups respectively. In benign group 2 cases recurred, in malignant group 4 cases recurred, and 3 had distant metastasis.ConclusionsPrimary retroperitoneal schwannomas are less common. It is difficult to make an accurate preoperative diagnosis. Surgery is the most effective therapy.Prognosis is good for benign and poor for malignant retroperitoneal neurilemomas.

Regulation of pancreatic cancer cells by fibroblast growth factor receptor-1 / 中华普通外科杂志

Objective To investigate the expression and regulation of FGFR1 protein and mRNA in human pancreatic cancer cell lines.Methods The expressions of FGFR1 protein and mRNA in pancreatic cancer cells were tested by Western blot,Northern blot and RT-PCR.The effects of exogenous growth factors and tyrosine kinase inhibitors on expression of FGFR1 protein and mRNA was observed.Results FGFR1 protein and mRNA expressed in 7 pancreatic cancer cell lines in different levels.After stimulation of several exogenous growth factors,we found that IGF-1,EGF and FGF2 up-regulated the expression of FGFR1 in Mia PaCa-2 significantly;EGF and FGF2 up-regulated the expression of FGFR1 in PANC-1 significantly (P＜0.05).The effect of FGF2 on the expression of FGFR1 was in time-dependent manner.ERK1/2 special inhibitor UO126 and p38 MAPK special inhibitor SB203580 down-regulated the expression of FGFR1.Conclusion Expression of FGFR1 is up-regulated by growth factors and may be modulated through ERK1/2 and p38 MAPK signal transduction pathway.

Diagnosis and surgical therapy of substernal goiter / 中华普通外科杂志

Objective To study the presentation,sensitivity of different diagnostic methods,snrgical modalities and pathological findings for patients of substemal goiter. Methods The clinical data of fifty nine cases of substernal goiter surgically treated were retrospectively analyzed. Results The main symptoms of substernal goiter patients were asymptomatic cervical mass(39/59),airway obstruction (13/59),hyperthyroidism(4/59),hoarseness(3/59)and choke(3/59).The sensitivity of chest X-ray,ultrasonography,CT and scintigraphy was 62.8%,15.8%,85.7%,and 50.0%respectively,and the specificity Was 99.4%,99.8%,99.5%and 99.0%,respectively.Standard cervical approach was successful for thyroidectomy operations in 57 cases.One patient underwent thyroidectomy by sternotomic approach,and another one by combined cervici-sternotomic approach.No major complications or perioperative deaths occurred.Pathology revealed nodular goiter in 48 cases.Grave's disease in one,thyroid adenoma in 2,and carcinoma in 8. Conclusions CT and chest X-ray are sensitive diagnostic techniques for substerual goiter.Cervical approach is appropriate for most substernal goiter.

Hedgehog signaling pathway activation in hepatocellular carcinoma / 中华普通外科杂志

Objective To investigate the expressions of Hedgehog sisnaling pathway genes in hepatocellular carcinoma tissues(HCC),and the effect of specific Hedgehog pathway inhibitor(KAADcyclopamine)on the growth of HCC cells and the expressions of Hedgehog genes. Methods The expression of Hedgehog signaling pathway components(Ihh,Ptch,Smo and Gli)was investigated in 14 HCC tissue slices,4 HCC cell lines and a normal hepatic cell line by using immunochemistry.The expression of Ihh,Ptch,Smo and Gli proteins was investigated in 9 HCC tissue specimens and 6 normal hepatic tissue specimens by using Western blotting.The expression of Ihh、Ptch、Smo、Gli and Hip genes was investigated by RT-PCR.Results The positive ratio of Gli,Ptch,Ihh and Smo were 42.9%,71.4%,71.4% and 85.7% in 14 HCC tissue slices,respectively.The expressions of Gli protein and Gii gene were up regulated while the expression of Hip gene was down regulated in HCC specimens compared with normal hepatic tissue specimens.Hedgehog signaling pathways in HCC cell lines HepG2,Bel-7402 and QGY-7701 were activated;KAAD-cyclopamine,a specific inhibitor of the Hedgehog signaling pathway,down regulated cell growth and the expressions of Ptch and Gli genes in the 3 HCC cell lines(Ptch gene:tHepG2=3.78,tBel-7402=9.03,tQGY-7701=5.63;Gli gene:tHepG2=9.61,tBel-7402=4.15,tQGY-7701=20.30,P＜0.05 in each group).The expression of Hip gene was up regulated in QGY-7701 after treated with KAAD-cyclopamine(t=4.70,P＜0.05).Conclusion The expression of main Hedgehog signaling pathway components were detected in HCC,KAAD-cyclopamine specifically inhibited the Hedgehog signaling pathway.

Apoptosis of human hepatoma cell lines induced by transforming growth factor beta 1 (TGF-β1) correlates with p53 and Smad4 activation / 北京大学学报(医学版)

Objective: To determine the relationships between apoptosis induced by transforming growth factor beta 1 (TGF-β1) and Smad in human hepatoma cell lines. Methods: Three human hepatic carcinoma cell lines, involving different status of the p53 gene respectively, were used in this study.TGF-β1-induced apoptosis in hepatic carcinoma cell lines was quantitated using the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. For identification of the mechanism of apoptosis induced by TGF-β1, these cell lines were transfected with a TGF-β1-inducible luciferase reporter plasmid containing Smad binding elements (SBE) and luciferase gene using LF2000, then were treated with TGF-β1. Relative luciferase activity was assayed respectively. Results: Among three cell lines studied with TUNEL assay, addition of TGF-β1 induced apoptosis only in HepG2 cells (wild type p53). In contrast, Huh-7 ( mutant p53) and Hep3B ( deleted p53) cell lines lacked apoptosis. The detection of luciferase activity indicated that HepG2 cells dramatically increased the response to TGF-β1 induction, Huh-7 and Hep3B cell lines significantly lowered luciferase expression. Conclusion: HepG2cells were highly susceptible to TGF-β1-induced apoptosis compared with Hep3B and Huh-7 cell lines.Smad4 may be a central mediator of the TGF-β1 signaling transdution pathway.

Colorectal cancer patients have oligoclonal proliferation of T cells in blood / 北京大学学报(医学版)

Objective: To study the clonal characteristics of peripheral T cells and anti tumor immunology in the patients with colorectal cancer by analyzing T cell receptor beta (TCR?) gene repertoire and complementarity determining regions 3 (CDR3) amino acid sequence of the peripheral blood cells (PBL). Methods:The 24 TCR?V genes from PBL in pre operation and post operation and colorectal cancer tissues, were amplified by the method of combined reverse transcriptase polymerase chain reaction (RT-PCR) with denaturation polyacrylamide sequencing gel eletrophoresis, which is called TCR? gene repertoire. In order to analyze the clonality of the over expressing bands and the CDR3 sequence, the PCR production was sequenced directly. Results: TCR? gene repertoire of PBL in the tumor bearing patients was clonally expressed, which indicated that there were monoclonal or oligoclonal expansion of T lymphocytes. Some of the clonal T cells in PBL had the same CDR3 amino acid sequence motifs with the clonal T cells in the tumor infiltrating lymphocyte(TIL). The patients with clonal expansion of T cells in PBL had lymph node metastases, but there was no recurrence within 10 months after operation. Conclusion: There is oligoclonal proliferation of T cells in the blood of tumor bearing patients. It is possible that the clonal T lymphocytes are the tumor associated antigen specific anti tumor T lymphocytes.

Outer Membrane Protein and ?-Lactamases in Imipenem Resistant Pseudomonas aeruginosa / 中华医院感染学杂志

OBJECTIVE To investigate the mechanisms for carbapenem resistance in clinical isolates of Pseudomonas aeruginosa from surgical intensive care unit(SICU).METHODS The minimal inhibitory concentrations(MICs) of various antibiotics were detected with agar dilution method;their ?-lactamases were extracted,types of their enzymes were identified and then their physical and chemical characteristics were studied by three dimentional extract test and isoelectric focusing(IEF) electropheresis;primers specific to IMP and VIM genes were utilized to amplify the metallo-?-lactamase genes.The levels of outer membrane protein OprD2 were measured by Western blot.RESULTS Forty one strains were resistant to imipenem from 49 strains of P.aeruginosa isolated from SICU during 3 years.Among them,34 isolates were found to produce high level of AmpC enzymes.Eight produced extended-spectrum ?-lactamases(ESBLs) at the same time.2 produced ESBLs only.No metallo-?-lactamases were detected.The activity of enzymes in the imipenem resistant group(74.32?53.42) was statistically different from the sensitive one(8.7?16.16,P

Study on the replace time of breathing machine humidification pot liquid in mechanical ventilation / 重庆医科大学学报

Objective:To study on the best replacement time of breathing humidification pot liquid in mechanical ventilation.Methods:33 mechanical ventilation patients were randomly divided into observation group and control group,in the observation group the humidification pot liquid were replaced 7 days,while in a control group were replaced every day,all liquid samples were cultured for bacteria.Results:119 samples collected in observation group have 3 cases with positive bacterial growth(2.5%),while 112 samples collected in control group have 15 cases with positive bacterial growth(13.4%).Conclusion:Replace humidification pot liquid of breathing machine everyday may cause bacterial pollution more easily than they were replaced in 7 days interval.