Objective:To investigate the role of an inflammatory microenvironment induced by Porphyromonasgingivalis ( P. gingivalis) in the occurrence of esophageal squamous cell carcinoma (ESCC) in mice. Methods:A total of 180 C57BL/6 mice were randomly divided into 6 groups, i.e. control group, P. gingivalis group, 4NQO group, 4NQO + P. gingivalis group, 4NQO + P. gingivalis + celecoxib group, and 4NQO + P. gingivalis + antibiotic cocktail (ABC, including metronidazole, neomycin, ampicillin, and vancomycin) group, with 30 mice in each group, using the random number table. All mice were normalized by treatment with ABC in drinking water for 2 weeks. In the following 2 weeks, the mice in the control group and the P. gingivalis group were given drinking water, while the other 4 groups were treated with 30 μg/ml 4NQO in the drinking water. In weeks 11-12, the mice in the P. gingivalis group, the 4NQO + P. gingivalis group, the 4NQO + P. gingivalis + celecoxib group, and the 4NQO + P. gingivalis + ABC group were subjected to ligation of the second molar in oral cavity followed by oral P. gingivalis infection thrice weekly for 24 weeks in weeks 11-34. In weeks 13-34, the mice in 4NQO + P. gingivalis+celecoxib group and 4NQO + P. gingivalis + ABC group were administered with celecoxib and ABC for 22 weeks, respectively. At the end of 34 weeks, gross and microscopic alterations were examined followed by RT-qPCR and immunohistochemistry to examine the expression profiles of inflammatory- and tumor-molecules in esophagi of mice. Results:At 34 weeks, 4NQO treatment alone did not affect the foci of papillary hyperproliferation, diseased area, and the thickness of the esophageal wall, but significantly enhanced the foci of hyperproliferation (median 1.00, P＜0.05) and mild/moderate dysplasia (median 2.00, P＜0.01). In addition, the expression levels of IL-6 [8.35(3.45,8.99)], IL-1β [6.90(2.01,9.72)], TNF-α [12.04(3.31,14.08)], c-myc [2.21(1.80,3.04)], pSTAT3, Ki-67, and pH2AX were higher than those in the control group. The pathological changes of the esophageal mucosa were significantly more overt in the 4NQO + P. gingivalis group in terms of the foci of papillary hyperproliferation (median 2.00), diseased area (median 2.51 mm 2), the thickness of the esophageal wall (median 172.52 μm), the foci of hyperproliferation (median 1.00, P＜0.05), and mild/moderate dysplasia (median 1.00, P＜0.01). In mice of the 4NQO + P. gingivalis group, the expression levels of IL-6 [12.27(5.35,22.08)], IL-1β [13.89(10.04,15.96)], TNF-α [19.56(6.07,20.36)], IFN-γ [11.37(8.23,20.07)], c-myc [2.62(1.51,4.25)], cyclin D1 [4.52(2.68,7.83)], nuclear pSTAT3, COX-2, Ki-67, and pH2AX were significantly increased compared with the mice in the control group. In mice of the 4NQO + P. gingivalis group, the diseased area, invasive malignant foci as well as pSTAT3 and pH2AX expression were significantly blunted by celecoxib. Treatment with ABC markedly reduced the papillary hyperproliferative foci, invasive malignant foci, and pSTAT3 expression but not pH2AX. Conclusions:P. gingivalis promotes the occurrence of esophageal squamous cell carcinoma in mice by inducing an inflammatory microenvironment primed with 4NQO induced DNA damage. Clearance of P. gingivalis with ABC or anti-inflammatory intervention holds promise for prevention of esophageal squamous cell malignant pathogenesis via blockage of IL-6/STAT3 signaling and amelioration of inflammation.

Objective:To investigate the role of an inflammatory microenvironment induced by Porphyromonasgingivalis ( P. gingivalis) in the occurrence of esophageal squamous cell carcinoma (ESCC) in mice. Methods:A total of 180 C57BL/6 mice were randomly divided into 6 groups, i.e. control group, P. gingivalis group, 4NQO group, 4NQO + P. gingivalis group, 4NQO + P. gingivalis + celecoxib group, and 4NQO + P. gingivalis + antibiotic cocktail (ABC, including metronidazole, neomycin, ampicillin, and vancomycin) group, with 30 mice in each group, using the random number table. All mice were normalized by treatment with ABC in drinking water for 2 weeks. In the following 2 weeks, the mice in the control group and the P. gingivalis group were given drinking water, while the other 4 groups were treated with 30 μg/ml 4NQO in the drinking water. In weeks 11-12, the mice in the P. gingivalis group, the 4NQO + P. gingivalis group, the 4NQO + P. gingivalis + celecoxib group, and the 4NQO + P. gingivalis + ABC group were subjected to ligation of the second molar in oral cavity followed by oral P. gingivalis infection thrice weekly for 24 weeks in weeks 11-34. In weeks 13-34, the mice in 4NQO + P. gingivalis+celecoxib group and 4NQO + P. gingivalis + ABC group were administered with celecoxib and ABC for 22 weeks, respectively. At the end of 34 weeks, gross and microscopic alterations were examined followed by RT-qPCR and immunohistochemistry to examine the expression profiles of inflammatory- and tumor-molecules in esophagi of mice. Results:At 34 weeks, 4NQO treatment alone did not affect the foci of papillary hyperproliferation, diseased area, and the thickness of the esophageal wall, but significantly enhanced the foci of hyperproliferation (median 1.00, P＜0.05) and mild/moderate dysplasia (median 2.00, P＜0.01). In addition, the expression levels of IL-6 [8.35(3.45,8.99)], IL-1β [6.90(2.01,9.72)], TNF-α [12.04(3.31,14.08)], c-myc [2.21(1.80,3.04)], pSTAT3, Ki-67, and pH2AX were higher than those in the control group. The pathological changes of the esophageal mucosa were significantly more overt in the 4NQO + P. gingivalis group in terms of the foci of papillary hyperproliferation (median 2.00), diseased area (median 2.51 mm 2), the thickness of the esophageal wall (median 172.52 μm), the foci of hyperproliferation (median 1.00, P＜0.05), and mild/moderate dysplasia (median 1.00, P＜0.01). In mice of the 4NQO + P. gingivalis group, the expression levels of IL-6 [12.27(5.35,22.08)], IL-1β [13.89(10.04,15.96)], TNF-α [19.56(6.07,20.36)], IFN-γ [11.37(8.23,20.07)], c-myc [2.62(1.51,4.25)], cyclin D1 [4.52(2.68,7.83)], nuclear pSTAT3, COX-2, Ki-67, and pH2AX were significantly increased compared with the mice in the control group. In mice of the 4NQO + P. gingivalis group, the diseased area, invasive malignant foci as well as pSTAT3 and pH2AX expression were significantly blunted by celecoxib. Treatment with ABC markedly reduced the papillary hyperproliferative foci, invasive malignant foci, and pSTAT3 expression but not pH2AX. Conclusions:P. gingivalis promotes the occurrence of esophageal squamous cell carcinoma in mice by inducing an inflammatory microenvironment primed with 4NQO induced DNA damage. Clearance of P. gingivalis with ABC or anti-inflammatory intervention holds promise for prevention of esophageal squamous cell malignant pathogenesis via blockage of IL-6/STAT3 signaling and amelioration of inflammation.

Objective: To isolate and identify Prevotella nigrescens (P.nigrescens) in gingival crevicular fluid of patients with chronic periodontitis and to analyze its tumor-promoting role in esophageal squamous cell carcinoma (ESCC). Methods: Samples of gingival crevicular fluid were collected from patients with chronic periodontitis and cultured on GAM agar medium under anaerobic conditions. Black colonies on GAM agar plates were picked for subculture, and then the bacteria were isolated and purified. Bacterial identification was conducted using Gram staining and 16S rDNA sequencing analysis. The isolated bacterial species was used to infect ESCC NE6-T cells and the changes in biological characteristics of the infected cells were evaluated. Results: Multiple bacterial colonies were observed after anaerobic culturing of gingival crevicular fluid samples for 120 h on GAM agar plates. A single bacterial colony with pure black and smooth appearance was obtained from grey black bacterial colonies with streak method. It was a Gram-negative bacterium with bead-like shape. It showed 99.78% 16S rDNA sequence identity with P. nigrescens F0103 and was named P. nigrescens LY01. P. nigrescens LY01 infection promoted the in vitro proliferation, migration and invasion of NE6-T cells and the growth of subcutaneous xenograft in nude mice. In addition, it could also induce the upregulation of Ki67 and activation of p-STAT3. Conclusions P. nigrescens inhabiting in gingival sulcus might promote the progression of ESCC in human with chronic periodontitis.

Objective:To investigate the surgical indications of gallbladder polyps.Methods:The retrospective case-control study was conducted. The clinicopathological data of 2 272 patients with gallbladder polyps who underwent cholecystectomy in 11 medical centers from January 2015 to December 2019 were collected, including 585 in the First Affiliated Hospital of Xi′an Jiaotong University, 352 in No. 215 Hospital of Shaanxi Nuclear Industry, 332 in the First People′s Hospital of Xianyang, 233 in Shaanxi Provincial People′s Hospital, 152 in the Second Affiliated Hospital of Xi′an Jiaotong University, 138 in Xianyang Hospital of Yan′an University, 137 in People′s Hospital of Baoji, 125 in Hanzhong Central Hospital, 95 in Baoji Central Hospital, 72 in Ankang Central Hospital, 51 in Yulin No.2 Hospital. There were 887 males and 1 385 females, aged (48±12)years, with a range from 12 to 86 years. Observation indicators: (1) surgical treatment, pathological examination and hospitalization; (2) follow-up and complications; (3) comparison of clinicopathological data between patients with non-neoplastic polyps and neoplastic polyps; (4) comparison of clinicopathological data among patients who had gallbladder polyp diameter of 7 to 9 mm, 10 to 12 mm, or ≥13 mm without cholecystolithiasis; (5) analysis of influence factors for the incidence of neoplastic polyps in patients who had gallbladder polyp diameter of 10 to 12 mm without cholecystolithiasis; (6) construction and evaluation of nomogram prediction model for neoplastic polyps of patients who had gallbladder polyp diameter of 10 to 12 mm without cholecystolithiasis. Follow-up using outpatient examination or telephone interview was conducted to detect complications and survival of patients up to April 2020. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was analyzed using the t test. Measurement data with skewed distribution were represented as M (range), and comparison between groups was analyzed using the rank-sum test. Ordinal data was analyzed using the rank-sum test of multi-samples. Analysis of influence factors for the incidence of neoplastic polyps was conducted after excluding missing data of CEA and CA19-9. Univariate analysis was conducted using the chi-square test or rank-sum test of multi-samples, and multivariate analysis was conducted using Logistic regression model. Based on Logistic regression model multivariate analysis, the nomogram prediction model was constructed using the R 3.6.0 version software. Results:(1) Surgical treatment, pathological examination and hospitalization: of the 2 272 patients, 2 199 cases underwent laparoscopic cholecystectomy, 43 cases underwent open cholecystectomy, 28 cases underwent radical resection for gallbladder carcinoma, and 2 cases underwent laparoscopic gallbladder preservation and polypectomy. There were 1 050 of the 2 272 patients undergoing intraoperative frozen section examination. Results of pathological examination showed that 1 953 of the 2 272 patients had non-neoplastic polyps including 1 681 cases with cholesterol polyps and 272 cases with inflammatory polyps; 319 cases had neoplastic polyps including 274 with benign polyps (93 cases with adenoma, 66 cases with adenomyoma, 81 cases with adenoma-like hyperplasia, 34 cases with adenoma combined with intraepithelial neoplasia); and 45 cases had malignant polyps including 43 cases with adenocarcinoma, 1 case with adenosquamous carcinoma and 1 case with sarcomatoid carcinoma. The duration of postoperative hospital stay of 2 272 patients was 3 days(range, 1 to 27 days). (2) Follow-up and complications: of the 2 272 patients, 1 932 were followed up for 3.5 to 63.5 months, with a median follow-up time of 31.0 months. During the follow-up, 180 patients had short-term complications and 170 patients had long-term complications. (3) Comparison of clinicopathological data between patients with non-neoplastic polyps and neoplastic polyps: cases with age ≤50 years or >50 years, cases with time from first discovery of polyp to operation <1 year, 1-3 years, >3 years and ≤5 years or >5 years, CEA, CA19-9, CA125, cases with single or multiple polyps in preoperative ultrasonography examination, cases with diameter of polyps in preoperative ultrasonography examination as 1-6 mm, 7-9 mm, 10-12 mm or ≥13 mm, cases with pedicled or broad based polyp wall in preoperative ultrasonography examination, cases with polyp morphology in preoperative ultrasono-graphy examination as nodular, papillary, globular or mulberry-like, cases undergoing or not undergoing intraoperative frozen section examination, cases with diameter of polyps in postoperative pathological examination as 1-6 mm, 7-9 mm, 10-12 mm or ≥13 mm, cases with gallbladder wall thickness in postoperative pathological examination as ≤4 mm or >4 mm of the 1 953 patients with non-neoplastic polyps were 1 118, 835, 1 027, 422, 230, 274, 2.0 mg/L(range, 0.2-8.6 mg/L), 14.5 U/mL(range, 2.6-116.4 U/mL), 10.5 U/mL(range, 1.2-58.7 U/mL), 658, 1 295, 674, 741, 413, 125, 1 389, 564, 407, 1 119, 292, 135, 832, 1 121, 698, 774, 385, 96, 1 719, 234, respectively. The above indicators of the 319 patients with neoplastic polyps were 160, 159, 204, 55, 26, 34, 2.9 mg/L(range, 0.2-28.8 mg/L), 19.7 U/mL(range, 3.5-437.1 U/mL), 15.0 U/mL(range, 1.0-945.0 U/mL), 203, 116, 49, 59, 100, 111, 154, 165, 92, 153, 49, 25, 218, 101, 53, 85, 90, 91, 263, 56, respectively. There were significant differences in the above indicators between the non-neoplastic polyps and neoplastic polyps patients ( χ2=5.599, Z=-3.668, -2.407, -3.023, -3.403, χ2=104.474, Z=-13.367, χ2=65.676, 12.622, 73.075, Z=-11.874, χ2=7.649, P<0.05). (4) Comparison of clinicopathological data among patients who had gallbladder polyp diameter of 7 to 9 mm, 10 to 12 mm, or ≥13 mm without cholecystolithiasis: after excluding 311 of the 2 272 patients with cholecystolithiasis, there were 706 cases with gallbladder polyp diameter of 7 to 9 mm, 459 cases with gallbladder polyp diameter of 10 to 12 mm, and 205 cases with gallbladder polyp diameter ≥13 mm, respectively. Cases with time from first discovery of polyp to operation <1 year, 1-3 years, >3 years and ≤5 years or >5 years, CEA, CA19-9, cases with single or multiple polyps in preoperative ultrasonography examination, cases with pedicled or broad based polyp wall in preoperative ultrasonography examination, cases with polyp morphology in preoperative ultrasonography examination as nodular, papillary, globular or mulberry-like, cases with echo intensity of preoperative ultrasonography examination as slightly strong, medium or weak, cases undergoing or not undergoing intraoperative frozen section examination, and cases with pathological types of polyps as non-neoplastic polyps, benign polyps or malignant polyps of the 706 patients with gallbladder polyp diameter of 7 to 9 mm were 291, 170, 107, 138, 2.2 mg/L(range, 0.5-8.6 mg/L), 21.0 U/mL(range, 2.8-116.4 U/mL), 207, 499, 620, 86, 118, 463, 75, 50, 252, 410, 44, 379, 327, 657, 49, 0, respectively. The above indicators of the 459 patients with gallbladder polyp diameter of 10 to 12 mm were 267, 85, 43, 64, 1.6 mg/L(range, 0.4-9.3 mg/L), 10.4 U/mL(range, 3.3-354.0 U/mL), 205, 254, 237, 222, 158, 223, 51, 27, 222, 213, 24, 263, 196, 373, 79, 7, respectively. The above indicators of the 205 patients with gallbladder polyp diameter ≥13 mm were 128, 38, 20, 19, 2.1 mg/L(range, 0.6-28.8 mg/L), 10.2 U/mL(range, 3.6-307.0 U/mL), 120, 85, 75, 130, 68, 97, 22, 18, 98, 95, 12, 148, 57, 113, 71, 21, respectively. There were significant differences in the above indicators among patients who had gallbladder polyp diameter of 7 to 9 mm, 10 to 12 mm, or ≥ 13 mm ( χ2=46.482, 8.093, 39.504, 66.971, 277.043, 60.945, 19.672, 22.340, 197.854, P<0.05). (5) Analysis of influence factors for the incidence of neoplastic polyps in patients who had gallbladder polyp diameter of 10 to 12 mm without cholecystolithiasis: of the 459 patients who had gallbladder polyp diameter of 10 to 12 mm without cholecystolithiasis, there were 373 cases with non-neoplastic polyps, and 86 cases with neoplastic polyps, respectively. Results of univariate analysis showed that CEA, CA19-9, the number of polyps in preoperative ultrasonography examination, diameter of polyps in preoperative ultrasonography examination, polyp wall in preoperative ultrasonography examination were influence factors for the incidence of neoplastic polyps in patients who had gallbladder polyp diameter of 10 to 12 mm without cholecystolithiasis ( χ2=10.342, 5.616, 20.009, Z=-4.352, χ2=6.203, P<0.05). Results of multivariate analysis showed that CEA>5.0 mg/L, CA19-9>39.0 U/mL, single polyp in preoperative ultrasonography examination, polyp diameter of 11 mm in preoperative ultrasonography examination, polyps of broad base in preoperative ultrasonography examination were independent risk factors for the incidence of neoplastic polyps in patients who had gallbladder polyp diameter of 10 to 12 mm without cholecystolithiasis ( odds ratio=8.423, 0.082, 0.337, 3.694, 2.318, 95% confidence interval: 1.547-45.843, 0.015-0.443, 0.198-0.575, 1.987-6.866, 1.372-3.916, P<0.05). (6) Construction and evaluation of nomogram prediction model for neoplastic polyps of patients who had gallbladder polyp diameter of 10 to 12 mm without cholecystolithiasis: CEA, CA19-9, the number of polyps in preoperative ultrasonography examination, diameter of polyps in preoperative ultrasonography examination, polyp wall in preoperative ultrasonography examination were imported into R 3.6.0 version software to establish the nomogram prediction model for neoplastic polyps. The results showed the score for CEA>5.0 mg/L, CA19-9>39.0 U/mL, cases with single polyp in preoperative ultrasonography examination, cases with polyp diameter of 10 mm in preoperative ultrasonography examination, cases with polyp diameter of 11 mm in preoperative ultrasonography examination, cases with polyp diameter of 12 mm in preoperative ultrasonography examination, polyps of broad base in preoperative ultrasonography examination were 25, 27, 100, 0, 26, 72, 98 in the nomogram prediction model, respectively. The C-index of nomogram prediction model was 0.768. Result of nomogram prediction model showed that the incidence of tumor polyps was 0, 6% and 10% in patients with multiple and pedicled gallbladder polyps with diameter of 10, 11, 12 mm and with CEA ≤5.0 mg/L and CA19-9 ≤39.0 U/mL, the incidence of tumor polyps was 43%, 53% and 70% in patients with single and broad base gallbladder polyps with diameter of 10, 11, 12 mm. The calibration curve showed that the probability of the nomogram prediction model predicting neoplastic polyps was nearly consistent with the actual probability. Conclusions:CEA>5.0 mg/L, CA19-9>39.0 U/mL, single polyp in preoperative ultrasonography examination, polyp diameter of 11 mm in preoperative ultrasonography examination, polyps of broad base in preoperative ultrasonography examination are independent risk factors for the incidence of neoplastic polyps in patients who had gallbladder polyp diameter of 10 to 12 mm without cholecystolithiasis. Cholecystectomy should be performed in time for patients with single and broad based gallbladder polyps with diameter of 10, 11, 12 mm.

Objective? To investigate the status of cancer-induced fatigue in patients with primary liver cancer (PLC) and its influencing factors. Methods? A total of 149 postoperative PLC patients undergoing surgical treatment during October 2015 to September 2017 in the Second Affiliated Hospital of Harbin Medical University were recruited by convenience sampling method. The general data questionnaire, Cancer-Related Fatigue Scale (CFS) and Social Support Rating Scale (SSRS) were used to investigate the patients. A total of 149 questionnaires were sent out and 120 valid questionnaires were collected. Results? The CFS score of the 120 postoperative PLC patients was (48.13±5.33). The difference in CFS scores of PLC patients with different education level, monthly income, medical expenses payment, duration of the disease, cognition of disease, chemotherapy and social support was statistically significant (P＜0.05). Multivariate linear regression analysis showed that the influencing factors of cancer-related fatigue in patients with PLC were medical expenses payment, duration of disease, cognition of disease, adjuvant chemotherapy and social support (P＜ 0.05). Conclusions? Cancer-related fatigue is a common problem in PLC patients and is affected by many factors. Clinicians need to combine with the actual situation of patients to develop more targeted individualized programs to alleviate the patient fatigue, improve patient social support, and further improve the quality of life of patients.

OBJECTIVETo compared the clinical efficacy of laparoscopic repair (LR) versus open repair (OR) for perforated peptic ulcers.

METHODSFrom January 2010 to June 2014, in Shanghai Tongji Hospital, 119 patients who were diagnosed as perforated peptic ulcers and planned to receive operation were prospectively enrolled. Patients were randomly divided into LR (58 patients) and OR(61 patients) group by computer. Intra-operative and postoperative parameters were compared between two groups. This study was registered as a randomized controlled trial by the China Clinical Trials Registry (registration No.ChiCTR-TRC-11001607).

RESULTSThere was no significant difference in baseline data between two groups (all P>0.05). No significant differences of operation time, morbidity of postoperative complication, mortality, reoperation probability, decompression time, fluid diet recovery time and hospitalization cost were found between two groups (all P>0.05). As compared to OR group, LR group required less postoperative fentanyl [(0.74±0.33) mg vs. (1.04±0.39) mg, t=-4.519, P=0.000] and had shorter hospital stay [median 7(5 to 9) days vs. 8(7 to 10) days, U=-2.090, P=0.001]. In LR group, 3 patients(5.2%) had leakage in perforation site after surgery. One case received laparotomy on the second day after surgery for diffuse peritonitis. The other two received conservative treatment (total parenteral nutrition and enteral nutrition). There was no recurrence of perforation in OR group. One patient of each group died of multiple organ dysfunction syndrome (MODS) 22 days after surgery.

CONCLUSIONLR may be preferable for treating perforated peptic ulcers than OR, however preventive measures during LR should be taken to avoid postopertive leak in perforation site.

China ; Comparative Effectiveness Research ; Digestive System Surgical Procedures ; adverse effects ; methods ; Enteral Nutrition ; Female ; Fentanyl ; Humans ; Laparoscopy ; adverse effects ; rehabilitation ; Laparotomy ; Length of Stay ; statistics & numerical data ; Male ; Multiple Organ Failure ; epidemiology ; Operative Time ; Pain, Postoperative ; drug therapy ; epidemiology ; Parenteral Nutrition, Total ; Peptic Ulcer Perforation ; rehabilitation ; surgery ; Peritonitis ; therapy ; Postoperative Complications ; epidemiology ; therapy ; Postoperative Period ; Prospective Studies ; Recurrence ; Reoperation ; Treatment Outcome

OBJECTIVETo assess the association of C677T and A1298C polymorphisms of methylenetetrahydrofolate reductase (MTHFR) gene with the susceptibility to polycystic ovary syndrome (PCOS).

METHODSBlood samples of 115 PCOS patients and 58 fertile women (for whom PCOS has been excluded) were collected for DNA extraction. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used for determining the C677T and A1298C polymorphisms. A database has been set up with Epidata and a significance test was performed with a statistical analysis system.

RESULTSA significant difference has been found in the allele frequencies of MTHFR gene 677 C and T polymorphisms between the two groups (P<0.01), for which T allele has increased the risk for PCOS by 2.06 times. Heterozygous and homozygous genotypes at position 677 (CT and TT) were more common among PCOS cases than controls, with an OR of 3.91 (95%CI: 1.70-8.97) and 4.39 (95%CI: 1.77-10.89), respectively. There was no statistical difference in genotypic distribution of MTHFR gene A1298C polymorphism (P>0.05). In the PCOS group, there was a significant difference with an OR of 6.40 (95%CI: 1.71-23.95) for an increased risk of insulin resistance in homozygous C677T mutations (TT) compared with the wild genotype (CC, P<0.01). The PCOS group and the control group also differed significantly in their red blood cell folate levels (P<0.01), but not in serum vitamin B12 and homocysteine levels (P>0.05).

CONCLUSIONMTHFR gene C677T polymorphism is associated with PCOS, for which CT and TT genotypes can increase the risk of PCOS. The TT genotype can also increase the risk of insulin resistance in PCOS patients. The A1298C polymorphism of the MTHFR gene is not associated with the occurrence of PCOS. The folate level in red blood cells of PCOS patients is lower, for whom folate should be supplemented.

Adolescent ; Adult ; Alleles ; Case-Control Studies ; Female ; Gene Frequency ; Genetic Predisposition to Disease ; Genotype ; Humans ; Methylenetetrahydrofolate Reductase (NADPH2) ; genetics ; Polycystic Ovary Syndrome ; enzymology ; genetics ; Polymorphism, Single Nucleotide ; Young Adult

OBJECTIVETo construct enterohemorrhagic Escherichia coli (EHEC) O157:H7 strains with delection espF gene and its nucleotide fragment and with espF gene complementation.

METHODSA pair of homologous arm primers was designed to amplify the gene fragment of kanamycin resistance, which was transformed into EHEC O157:H7 EDL933w strain via the PKD46 plasmid by electroporation. The replacement of the espF gene by kanamycin resistance gene through the PKD46-mediated red recombination system was confirmed by PCR and sequencing. The entire coding region of espF along with its nucleotide fragment was amplified by PCR and cloned into pBAD33 plasmid, which was transformed into a mutant strain to construct the strain with espF complementation. RT-PCR was used to verify the transcription of espF and its nucleotide fragment in the complemented mutant strain.

RESULTS AND CONCLUSIONWe established EHEC O157:H7 EDL933w strains with espF gene deletion and with espF gene complementation. Both espF and its nucleotide fragment were transcribed in the complemented mutant strain. The two strains provide a basis for further study of the regulatory mechanism of espF.

Carrier Proteins ; genetics ; DNA Primers ; Escherichia coli O157 ; genetics ; Escherichia coli Proteins ; genetics ; Gene Deletion ; Plasmids ; Polymerase Chain Reaction

OBJECTIVETo construct enterohemorrhagic Escherichia coli (EHEC) O157: H7 ppk gene deletion strains and study its biological characteristics.

METHODSThe gene fragment of kanamycin resistance was amplified using a pair of homologous arm primers whose 5' and 3' ends were homologous with ppk gene and kanamycin resistance gene, respectively. EHEC O157: H7 EDL933w competent strains were prepared and transformed via electroporation with the amplification products. The ppk gene was replaced by kanamycin resistance gene using pKD46-mediated Red recombination system. The recombinant strain was confirmed by PCR and sequencing, and its morphology, growth ability and adhesion were assessed using Gram staining, OD600 value and Giemsa staining.

RESULTS AND CONCLUSIONWe established a ppk-deleted EHEC O157:H7 EDL933w strain with kanamycin resistance and compared the biological characteristics of the wild-type and mutant strains, which may facilitate further study of the regulatory mechanism of ppk gene.

DNA Primers ; Escherichia coli O157 ; genetics ; Escherichia coli Proteins ; genetics ; Gene Deletion ; Phosphotransferases (Alcohol Group Acceptor) ; genetics ; Polymerase Chain Reaction

Objective To construct enterohemorrhagic Escherichia coli (EHEC) O157: H7 ppk gene deletion strains and study its biological characteristics. Methods The gene fragment of kanamycin resistance was amplified using a pair of homologous arm primers whose 5' and 3' ends were homologous with ppk gene and kanamycin resistance gene, respectively. EHEC O157:H7 EDL933w competent strains were prepared and transformed via electroporation with the amplification products. The ppk gene was replaced by kanamycin resistance gene using pKD46-mediated Red recombination system. The recombinant strain was confirmed by PCR and sequencing, and its morphology, growth ability and adhesion were assessed using Gram staining, OD60 value and Giemsa staining. Results and Conclusion We established a ppk-deleted EHEC O157:H7 EDL933w strain with kanamycin resistance and compared the biological characteristics of the wild-type and mutant strains, which may facilitate further study of the regulatory mechanism of ppk gene.