Objective Streptococcus sanguis is a possible candidate bacterium for the caries replacement therapy, which has no advantages in the acidic environment.The aim of the study was to construct acid-resistant strains of Streptococcus sanguis, determine its acid tolerance, and explore the mechanism of its antagonism against Sterptococcus mutans.Methods By gradually reducing the pH value of the medium, we constructed acid-resistant strains of Streptococcus sanguis, observed their growth and measured their acid tolerance according to their survival rate against lethal pH.We evaluated the competitive relationship between Streptococcus sanguis and Streptococcus mutans by plate experiment and detected the changes of related acid resistance genes by real-time quantitative PCR.Results The growth of Streptococcus sanguis and its acid-resistant strains were limited by the pH value, and that of Streptococcus sanguis was better in either acidic or normal environment.The lethal pH value of Streptococcus sanguis was 3.6, that of its acid-resistant strains was 2.3, and the survival rate of the acid-resistant strains was 66.59% in the pH 3.6 environment.In comparison, the lethal pH value of Streptococcus mutans was 2.5, that of its acid-resistant strains was 2.1, and the survival rate of the acid-resistant strains was 2.55% in the pH 2.5 environment.In the presence of chloramphenicol, the acid-resistant strains could not survive in the original lethal pH.In the sub-lethal pH environment, the expressions of the acid resistance-related genes Groel and Dnak in the acid-resistant strains were significantly up-regulated as compared with those in the original Streptococcus sanguis (P<0.05).Conclusion Streptococcus sanguis has an acid adaptability and can enhance acid resistance in the sub-lethal pH environment.Acid-resistant Streptococcus sanguis in the replacement therapy may provide some new ideas for the treatment of dental caries.

Objective: To investigate the antitumor actions of polysaccharide extracts from the fruiting body of coriolus versicolor (CVE). Methods:Hepatoma HepA cells were injected into mice subcutaneously. Different doses of CVE were given by gavage. On the 7 th and 14 th day, tumor inhibitive rates were calculated. ELISA was performed to measure the serum IgG level; MTT was used to examine CVE′s effects on the proliferation of T lymphocytes of thymus. Immunohistochemistry was used to determine CVE′s influence on the expression of tumor related genes P53 and VEGF in liver. Results: CVE may evidently inhibit the growth of the transplanted HepA tumors. Its effects on the serum IgG level and on the proliferation of T lymphocytes of thymus were also significantly. Also, CVE markedly decreased the expression of P53, VEGF genes in liver. Conclustion: CVE had significant antitumor effects in vivo . The mechanisms may involve immune modulation effects and antimetastasis actions.

Objective To summarize the clinical and pathological features of exaggerated placental site (EPS),explore its pathogenesis regularity,diagnosis and treatment strategies.Methods The clinical data related to 34 patients with EPS were analyzed retrospectively.Results In 34 patients,11 patients performed full-term cesarean section,2 patients performed normal vaginal delivery,the other 21 patients had abortion.Thirty-one patients had pregnancy history.Fifteen patients performed hysterectomy,13 patients performed dilatation and curettage,6 patients performed exploratory hysteroscopy and lesions resection.All the patients survived after treatment.Conclusions The patients can not be diagnosed in the antepartum and intrapartum,but can be diagnosed relying on the pathological diagnosis.When it is ineffective to stop bleeding after delivery or abortion by conventional treatment,we should consider the possibility of EPS.Timely perform hysterectomy is theeffective method to stop bleeding,can save the life of patients.If bleeding is not much,curettage or exploratory hysteroscopy can get a significant effective treatment and avoid hysterectomy.

Objective Toinvestigatethevalueofimagingdiagnosisofthe lymphangioleiomyomatosis( LAM ).MethodsFifteen patients with LAM confirmed by pathological assessment were analyzed retrospectively for radiologic findings.They had chest radiograph, chest highresolution CT (HRCT),abdominal CT, direct lymphangiography(DLG), chest CT and abdominal CT after DLG.Results Chest radiograph findings included normal (1),increasing of lung markings (3),disseminated honeycomb or reticular pattern ( 11 ), pneumothorax ( 2 ), and pleural effusion ( 14 ). Chest conventional CT and HRCT showed typical imaging manifestation of PLAM in all cases, including sporadic or disseminated cysts in bilateral lungs. According to the grading standard of pulmonary disease made by Avila et at, there were 3 cases in grade Ⅰ , 5 cases in grade Ⅱ and 7 cases in grade Ⅲ . Fourteen of 15 patients with LAM had positive abdominal CT findings in retroperitoneum and pelvic cavity. Common abdominal CT findings included cystic lymphangioma in 9 of 14 patients, lymphangiomyoma in 13 and both coexisting in 7.One of the14patients alsohadhepaticlipomaandangiomyolipomas.Onepatienthadrenal angiomyolipomas; and one patient had hysteromyoma. All 15 cases underwent DLG, 1 cases had lymphatic obstruction in the lumbar 3 level, the remaining 14 cases had varying degrees of thoracic duct stenosis, or obstruction. Neck trunk, subclavian trunk and bronchial trunk showed lymphatic reflux. On post-DLG CT,thoracic duet outlet obstruction was not demonstrated in 3 cases, the remaining 12 cases showed thoracic outlet obstruction, consistent with the DLG findings.Conclusion HRCT is a useful diagnostic method showing characteristic findings of PLAM. MSCT can help to detect abdominal LAM. DLG and MSCT after DLG have value in displaying obstruction site of thoracic duct or lymphatic trunks and provide guidance for operative treatment.

Objective To synthesize 99Tcm-TP5-3 and evaluate its biodistribution and kinetics as a molecular probe for the detection of apoptosis,and evaluate tumor apoptosis after a single dose of paclitaxel chemotherapy in MDA-MB-231 breast tumor model.Methods TP5-3 was labeled with 99Tcm directly,and analyzed with HPLC.The radioactivity in tissues was measured and expressed as ％ID/g and T/NT (tumor/muscle).The mice bearing MDA-MB-231 breast tumor were divided into two groups:the treatment group which was given a single dose of paclitaxel (40 mg· kg-1,via tail vein),and the control group which was injected with the same volume of normal saline.After therapy,99Tcm-TP5-3 was injected via tail vein in both groups (100 μ1 for each mouse).MicroSPECT/CT was performed at 3 h postinjection.Radioactivity in different tissues was determined after imaging.Apoptotic cells were measured with flow cytometry.The morphological changes of the apoptotic cells were observed by light microscopies.One-way analysis of variance,two-sample t test and linear correlation analysis were used to analyze the data.Results The radiolabeling efficiency was ＞ 95％ and the radiochemical purity of 99Tcm-TP5-3 was (96.0± 1.5)％ at room temperature for 4 h.The predominant uptake was found in the kidneys at 30 min postinjection ((8.48± 1.07) ％ID/g),with rapid tracer clearance from the circulation.By comparison with activity at 5 min postinjection ((13.74± 4.21) ％ID/g),85％ of the initial activity reduced in blood at 4 h ((2.07±0.35) ％ID/g; F=11.310,P＜ 0.05).99Tcm-TP5-3 was mainly accumulated in the kidneys,liver and stomach,and excreted via the kidneys.T/NT in the treated group was 4.21±0.06,which was significantly higher than that of the control group (1.57±0.67; t =12.820,P＜0.05).The radioactivity of tumor tissue in the treatment group was much higher than that in the control group (4.82±0.54) ％ID/g vs (1.44±0.38) ％ID/g,t=0.679,P＜0.05).The tumor uptake of 99Tcm-TP5-3 in the treatment group positively correlated well with the apoptotic cells (r =0.985,P＜0.05).Histopathology further confirmed that a large number of apoptosis had occurred in the tumor after paclitaxel treatment.Conclusion 99Tcm-TP5-3 appears to have potential to be a useful molecular probe for imaging tumor cell apoptosis.

Most main oilfields in China have already entered a "double high" development stage (high water cut, high recovery degree). To further enhance oil recovery in reservoirs after polymer flooding (RAPFs), an efficient activator formulation for promoting metabolism of endogenous microorganism was studied by aerogenic experiments, physical simulation experiments, electron microscopy scanning and pyrophosphate sequencing. Results show that the activator could activate the endogenous microorganisms in the injected water and make the pressurized gas reach 2 MPa after 60 d static culture of the activator in a high pressure vessel. The oil recovery efficiency of natural core physical simulation flooding can be improved by more than 3.0% (OOIP) in RAPFs when injected 0.35 PV activator with 1.8% mass concentration, and a lot of growth and reproduction of activated endogenous microorganism in the core was observed by electron microscopy scanning. Field trial with 1 injector and 4 producers was carried out in the east of south II block of Sa Nan in December 2011. By monitoring four effective production wells, changes of carbon isotope δ13C (PDB) content of methane and carbon dioxide were -45 per thousand to -54 per thousand and 7 per thousand to 12 per thousand. Compared with east II of Sa Nan block, the oil amount increased by 35.9%, water cut stabled at 94%. The incremental oil was 5 957 t during the three and a half years, which provides an alternative approach for further improving oil recovery in similar reservoirs.
Carbon Dioxide ; chemistry ; Carbon Isotopes ; analysis ; China ; Diphosphates ; chemistry ; Methane ; chemistry ; Oil and Gas Fields ; microbiology ; Polymers ; Water ; Water Microbiology

Animals ; Aorta ; drug effects ; physiology ; Blood Pressure ; drug effects ; Cadmium ; toxicity ; Female ; In Vitro Techniques ; Male ; Muscle, Smooth, Vascular ; drug effects ; physiology ; Rabbits ; Vasoconstriction ; drug effects

The course of estahlishing coronary collateral circulation has been studied after ligating the anterior descending branch of the left coronary artery (L. A. D.) of the heart in 20 rabbits. Another 5 rabbits were studied as control group. The experimental results were as follows: (1) The rabbit electrocardiograms EGG were made before and after the ligation of the L. A. D. The EGG of control group was made only before killing. In these experiments, the pathological changes of No. 28 were observed immediately after ligating the L. A.D. It was found that the T wave was inverted in standard lead I, and that the volts of the QRS complex in lead Vc fell apparently. This phenomenon may be interpreted as myocardial ischemia in the anterior wall of the heart. After ligating the L. A. D. the S-T segment of No. 27 in AVL lead elevated and exceeded I mm, and the depressive Q wave in Vc lead was greater than the one-fourth of the R wave before killing. All of the phenomenen observed in the rabbit entirely confirmed the myocardial infarction and myocardial ischemia. In No. 25, the T wave was inverted in standard lead I, and the QRS complex in lead Vc was not only shallow in depth but also very little. The conditions accounted probably for myocardial ishcmia. During 4 to 21 days after ligating the L. A. D.,the pathological changes in the EGG occurred frequently.The rabbit ECG gradually became normal from 21 st day on. (2) The coronary arteries of the rabbit hearts were injected with X-ray contrast medium and were examined. The X-ray film thus obtained were compared with the specimen after they were cleared. At the same time, sections of the heart walls (the infarcted area and its surrounding areas) of fifteen rabbits were studied carefully under microscope. Our primary impression was that only a few newly formed vessels in the central part of the infarct till the fourth day after ligating the L. A. D. The vessels surrounding of the infarct show a slight winding and distension. During 10 to 28 days, the number of the newly formed vessels in the infarct increased gradually day by day. The vessels surroundings the infarct were also highly crooked and distended, especially in the anterior wall of the right ventricle. This is possibly the most active period in the establishment of coronary collateral circulation. During 28 to 49 days, the morphology of the vessels in the infarct area became similar to that of the corresponding area of the control group. (3) The significance of the coronary collateral circulation on the heart wall was discussed.

A Study of one hundred hearts (adults 56, children 44) has been made. The S-A mode arteries and A-V node arteries are measured and analysed. The chief results are as fo11ows: (1) 67% of S-A node arteries originated from the right coronary artery; 33% arose from the left coronary artery. A number of the S-A node arteries arising from the right coronary artery were the continuation from the anterior right atrial branch. Occasionally, they may be come from the intermediate right atrial branch or intermediate left atrial branch. (2) The distance between the right S-A node artery origin and the aortic root was about 1.28?0.12 cm in adults, and 0.85?0.09 cm in children, while between the left S-A node artery origin and the bifurcation of the left coronary artery, it was about 0.84?0.19 cm in adults and 0.41?0.03 cm in children. The external diameters of the S-A node arteries were measured. The mean value was as follows: 0.17?0.01 cm (adults); 0.12?0.01 cm (children). (3) The relation between the origins of S-A node artery and A-V node artery may be divided into six types. ①The S-A node artery and A-V node artery which originated from the right coronary artery were about 58.06%. ②The S-A node artery arising from the left coronary artery and the A-V node artery originating from the right coronary artery occurred in 30.11% ③The S-A node artery originated from the right coronary attery, while the A-V node artery arose from the left. This condition was about 6.45%.④The type that the S-A node artery arose from both coronary arteries, and the A-V node artery originated from the right was about 3.22%.⑤Both the S-A node artery and A-V node artery arising from left coronary artery occurred in 1.08%.⑥The A-V node artery originating from the left and right coronary arteries, and the S-A node artery arising from the right coronary artery were about 1.08%.

Observations on the coronary arteries of 100 embalmed hearts from 56 adults and 44 children, have been made. The results are as follows: (1) The point of origin of coronary arteries was found vertically on the margin of the aortic sinus in 69.4% of the left and 52.8% of the right respectively and horizontally at the middle third of the aortic sinus in 79.7% of the left and 67.5% of the right respectively. (2) The external diameter at the opening of the left coronary artery is greater than the right in both adults and children. The mean value of the external diameter at the opening of the left coronary arteries was 0.41?0.14 cm and of the right 0.31?0.02 cm, in children, while in adult, the figures were 0.53?0.02 cm and 0.45?0.02 cm respectively. (3) The accessory coronary artery occurred in 10%.The percentage is lower than other reports in China. (4) The branch and distribution of the left coronary artery were studied thoroughly; its diagonal branch occurred in 38.4%.The mean value of the angle between the left anterior descending branch and the left circumflex artery was about 80?. In one the left circumflex artery was absent. (5) The branch and distribution of the right coronary artery were also investigated carefully. Fifty six percent of the right coronary arteries terminate in the heart, diaphragmatic surface between the crux of the heart and the obtuse margin. The posterior descending branch of right coronary artery ended in the middle-lower third of the posterior longitudinal sulcus of the heart. The occurrence of desending septum artery is 6.1%. (6) An investigation on the posterior superior septum artery and Kugel’s artery has been made: the former, 45.5% of which originated from the right coronary artery, possessed only one branch while the latter, which has been seen in three cases, occurred in 30%. (7) The common type of distribution, in which the posterior wall of the left ventricle was supplied by the right circumflex branch, occurred in 80.2%.