Recombinant PCR applies to fulfill gene recombination by PCR thermal reaction.Over the twenty years,it has branched into three characteristic strategies:splicing by overlapping extension(SOE),jumping polymerase chain reaction(JPCR)and DNA shuffling.Recently,the technique aimed with exploiting natural source of different allele genes is developing up on simplification of experimental procedure,on trap for mutation and variation,and on highthroughput screening with technology of surface display and fluorescent probe.The recombinant PCR is increasesing value in broad range from biological basic research to bioengineering study.

Adult ; Aged ; China ; epidemiology ; Female ; Humans ; Logistic Models ; Male ; Middle Aged ; Multivariate Analysis ; Nasopharyngeal Neoplasms ; epidemiology ; etiology ; Risk Factors

BACKGROUND:Chronic obstructive pulmonary disease is progressive respiratory disease characterized by airflow limitation.
OBJECTIVE:To investigate the therapeutic effect of adipose-derived mesenchymal stem cel transplantation in rats with chronic obstructive pulmonary disease.
METHODS:Sixty healthy male Sprague-Dawley rats were randomly divided into control, model and treatment groups (n=20 per group). Rat models of chronic obstructive pulmonary disease were made in the model and treatment group, while no treatment was done in the control group. After modeling, rats in the treatment group were given tail vein injection of CM-Dil-labeled adipose-derived mesenchymal stem cel s, and rats in the model and control groups given the same amount of normal saline. Rat pulmonary ventilation function, inflammatory factor level and pathological changes of the lung were detected at 14 days after cel transplantation.
RESULTS AND CONCLUSION:After modeling, reduced lung function was found in rats with chronic obstructive pulmonary disease, but the cel transplantation significantly improved this reduction (P<0.05). Compared with the model group, significantly reduced indexes were visible in the treatment group (P<0.05), including the total number of white blood cel s, the number of macrophages and neutrophils, levels of interleukin-8, tumor necrosis factorαand C-reactive protein in the bronchoalveolar lavage fluid as wel as serum level of malondialdehyde, while serum superoxide dismutase activity was increased significantly in the treatment group (P<0.05). In the treatment group, emphysema-like changes were mitigated and CM-Dil-labeled adipose-derived mesenchymal stem cel s were capable of homing to the lung tissue of rats with chronic obstructive pulmonary disease and survived. Al these findings show that adipose-derived mesenchymal stem cel transplantation can improve lung function of rats with chronic obstructive pulmonary disease, and reduce inflammatory response, which has for certain some therapeutic effects.

As highly active anti-retroviral therapy continues, large numbers of drug-resistant strains appeared in human immunodeficiency virus ( HIV) infectors, which always leads to a decline of treatment results or even a treatment failure.The genotypic resistance analysis technique of the bioinformatics is a powerful tool to forecast the HIV resistance and also determines the success or failure of antiviral therapy.This review will be focus on the advantages and disadvantages, influence factor of the genotype resistance prediction and improve measure of the primary HIV drug resistance genotype interpretation system, depending on the principle and characteristics of the genotypic drug resistance analysis as the breakthrough point, in order to provide guidance for reasonable application of different genotypes drug resistance analysis system in China.

Objectives To study the effects of effective constituent of Cortex Moutan-Paeonol and Paeoniflorin on myocardial ischemia and myocardial infarction in experimental canines.Methods The coronary artery ligation was employed to establish the model of canines with acute myocardial ischemia and myocardial infarction.The extent of myocardial ischemia was detected by epicardial-electrocardiogram and the extent of infarction was determined by N-BT staining method.Results The adminstration of Paeonol and Paeoniflorin reduced the myocardial ischemia level(P

Objective:To mutate the codons which code the lysine at loci ? 99 ,? 82 in human hemoglobin gene to the codons which code the cystein.Methods:The objective gene to be mutated was cloned into pAlter Ex2 plasmis and then was mutated with the site directed mutagenesis mediated by oligonucleotide.Results:The sequencing of clones obtained by preliminary screening showed that the anticipated results were reached without any unexpected mutation.Conclusion:The results lay a foundation for the further development of research on expression and purification of recombinated mutant human hemoglobin gene.

Objective To make an attempt to express serialy the human ?,? globin in Escherichia Coli in order to carry out the research on blood substitute based on the genetic recombination of hemoglobin.Methods The routine molecular biology technology was used.Results The serial genetic fragment of ?,? globins containing the hemoglobin was amplified by PCR.The genetic sequencing showed that there was no unexpected mutation.And then,the serial genes were cloned into the pBV220 expression carrier.Undergoing thermal inducement,the expression product could reach about 20% of total bacterial protein.The expression product assumed the form of inclusion body,and it was vertified by Western Blotting.Conclusion This much can lay the solid foundations for further launching the research on expression and pruification of recombinant human hemoglobin genes.

Objective:To compare the effects of rotational night shifts on the micturition patterns of fe-male nurses.Methods:A total of 58 nurses without lower urinary tract symptoms were recruited,who worked in the Peking University People’s Hospital during January and June in 2014.The nurses aged 20 -43 years were divided into two groups,the night-shift group (n =28)and the non-shift group (n =30).The alcohol or coffee intaking were forbidden.In the night-shift group,nurses had worked on rota-tional shifts for at least 6 months.Their average age was (26.75 ±4.11)years.In the non-shift group, nurses took regular day-time work,whose average age was (27.80 ±5.60)years.A voiding diary was kept for 7 consecutive days at the end of 6 months,starting 2 days before their night duties until 4 days after completion of their night duties.For comparison,the non-shift group with regular shifts completed a 7-day voiding diary.In the 7-day recording voiding diary,the nurses were required to have the normal in-take of liquid about 1 500 -2 000 mL/d.The frequency volume charts of nocturia,the 8-hour interval urine production and frequency were compared between the two groups.Results:Nocturia frequency was increased in the night-shift group [0.5 (0 -2.4)]compared with the non-shift group [0 (0 -2),P =0.02].The volume of nocturia was increased in the night-shift group [125 mL (0 -660 mL)]compared with the non-shift group [0 mL (0 -340 mL),P <0.01].The 8-hour interval indices showed that urine production changed with shift (P <0.01).In the consecutive 7 days,the nocturnal volume of the night-shift group increased on the day after night shift.When the night-shift nurses returned to daytime duty, the volume of urine decreased but nocturnal urine production remained high,and the frequency of noctu-ria also increased significantly (P <0.05).Compared with the 8-hour interval indices,the night-shift group’s voiding volume [(542.35 ±204.66)mL]and voiding frequency (2.24 ±0.69)were more than those of the non-shift group at the afternoon time (from 2 pm to 10 pm).During the 8 h interval night time (from 10 pm to 6 am),the volume of nocturia in the night-shift group [(309.74 ±162.74) mL]was more than that in the non-shift group [(199.38 ±153.98)mL,P =0.01];the frequency of nocturia in the night-shift group (1.31 ±0.52)was increased than that in the non-shift group (0.82 ± 0.55,P <0.01).Conclusion:The rotational shifts affect the micturition patterns of nurses who go through the night shift work,which increases the volume and frequency of the nocturia.

Aim Drug repositioning is to find new indications for existing drugs,however,potential drug-disease relationships are often hidden in millions of unknown relationship.With the analyzing of medical big data,we predict the potential drug-dis-ease relationships.Methods Based on the assumption that similar drugs tend to have similar indications,we applied a rec-ommendation-based strategy to drug repositioning.First,we col-lected the information of known drug-disease therapeutic effect, side effect,drug characters and disease characters;second,we calculated the drug-drug similarity measurements and disease-disease similarity measurements;last,we used a collaborative filtering (CF)method to predict unknown drug-disease relation-ships based on the known drug-disease relationships by integra-ting the similarity measurements,and built a ranking list of pre-diction results.Results The experiments demonstrated that a-mong the TOP 500 of the list,1 2.8% were supported by clinical experiments or review,and 20% were supported by model or-ganism or cell experiments.Conclusion Compared to the clas-sification model and random sampling results,the CF model can effectively reduce the false positives.

BACKGROUND:In foreign animal experiments and clinical reports, microporous polysaccharide hemospheres are characterized as good hemostatic effect, no delayed bleeding, good biocompatibility, and no adverse reactions in the body. OBJECTIVE:To assess the efficacy and safety of microporous polysaccharide hemospheres on reducing blood loss after unilateral total hip arthroplasty. METHODS:Totaly 98 patients who received unilateral total hip arthroplasty due to femoral neck fractures, 39 males and 59 females, aged 61-77 years, were randomly divided into two groups: test group, treated with 1g microporous polysaccharide hemospheres before suture of wound; control group, treated with electric coagulation hemostasis before suturing. Drainage tubes were placed in the two groups. Hemoglobin, blood loss, alogeneic transfusion rate, drainage volume, coagulation index and incidence of deep venous thrombosis of the lower limbs were compared. RESULTS AND CONCLUSION:The total blood loss, drainage volume, and transfusion rate in the test group were significantly lower than those in the control group (P < 0.01), but there were no differences in D-dimer, platelet count, activated partial thromboplastin time and international normalized ratio between the two groups. One case of each group developed deep venous thrombosis of the lower limbs, and no significant difference was in the incidence of deep venous thrombosis between the two groups. No infection occurred. These findings indicate that microporous polysaccharide hemospheres that are safe, effective and convenient can reduce the visible and hidden blood loss after unilateral total hip arthroplasty.