Chromosomal integration of large DNA fragments in microorganisms: a review / 生物工程学报

The modern bio-fermentation industry requires design and creation of efficient microbial cell factories for directed conversion of raw materials to target products. The main criteria for assessing the performance of microbial cell factories are their product synthesis capacity and stability. Due to the deficiencies of plasmids in gene expression such as instability and being easy to lose, integration of genes into chromosome is often a better choice for stable expression in microbial hosts. To this end, chromosomal gene integration technology has received much attention and has developed rapidly. In this review, we summarize the recent research progresses of chromosomal integration of large DNA fragments in microorganisms, illustrate the principles and features of various technologies, highlight the opportunity brought by the CRISPR-associated transposon systems, and prospect future research direction of this technology.

A young patient with recurrent myocardial infarction within a half month / 中南大学学报(医学版)

In this study, we reported a young male patient with acute chest pain who was diagnosed as myocardial infarction. The regular medication was performed following coronary intervention. Under such condition, this patient had 3 times myocardial infarction within a half month. The laboratory results showed that there might be a state of hypercoagulability. Aspirin combined with clopidogrel and other treatment were administrated. Meanwhile, the examination demonstrated that there was aspirin-resistant in the patient. The antiplatelet drug and extended anticoagulation therapy were carried out. There was no further myocardial infarction, and no coronary arteries stenosis was found in the re-examination angiography. Aspirin resistance and hypercoagulability should be considered when patients occurred the repeated myocardial infarction after regular medication and coronary intervention. Replacement of the antiplatelet treatment or combination with anticoagulant therapy is necessary in similar patient to avoid the sever consequence.

A new ECG sign for sudden death: Transient prolonged QT interval following premature contraction / 中南大学学报(医学版)

Early recognition and treatment for early warning electrocardiogram (ECG) of sudden death are very important to prevent and treat malignant arrhythmia and sudden death. Previous studies have found that R-on-T and T wave alternation, and QT interval prolongation are closely related to malignant arrhythmia or sudden death, which are included in the critical value of ECG.By analyzing the ECG characteristics of 4 patients with sudden death, we found that although the causes of the patients were different, there were transient prolongation of QT interval after premature contraction in 12 lead ECG, followed by malignant arrhythmia or sudden death. Thus, we thought that the transient prolongation of QT interval after premature contraction had a high value for warning malignant arrhythmia or sudden death. This phenomenon should be paid enough attention to reduce the risk of sudden death.

Progress in biological utilization of formic acid / 生物工程学报

The use of microbial cell factories to achieve efficient conversion of raw materials and synthesis of target substances is one of the important research directions of synthetic biology. Traditional industrial microorganisms have mainly used sugar-based raw materials as fermentation substrates. How to adopt cheaper carbon resources and realize their efficient use has been widely concerned. Formic acid is an important organic one-carbon source and widely used in industrial manufacturing of pesticides, leather, dyes, medicine and rubber. In recent years, due to the demand fluctuation in downstream industries, formic acid production is facing the dilemma of overcapacity, and therefore, requiring new conversion paths for expansion and extension of the related industrial chain. Biological route is one of the important options. However, natural formate-utilizing microorganisms generally grow slowly when metabolizing formic acid, and moreover, are difficult to be artificially modified by the absence of effective genetic tools. Construction of non-natural formate-utilizing microorganisms is another alternative strategy, but still in its infancy and has a huge space for further improvements. Here, we briefly summarize the recent research progress of biological utilization of formic acid, and also propose the future research focus and direction.

Clinical practice of transnasal endoscopic operation for retrobulbar lesions / 中华耳鼻咽喉头颈外科杂志

Objective@#To summarize the skill and experience of transnasal endoscopic operation for retrobulbar lesions.@*Methods@#Seven patients aged from 25 to 67 years old diagnosed as retrobulbar lesions who underwent transnasal endoscopic operation in Department of Otorhinolaryngology Head and Neck Surgery, Xiangya Hospital between January 2013 and October 2016 were retrospectively analyzed. Two males and five females were included in this study. Five patients underwent transnasal endoscopic operation via media rectus-inferior rectus space, with the other 2 cases via media rectus-superior rectus space.@*Results@#Total lesion removal was achieved in 6 of 7 patients, while 1 patient underwent subtotal removal of the lesion. The visual acuity and visual field improved in 3 cases. The pathological examination showed hemangioma(5 cases), bone cyst(1 case) and fibroma(1 case). All patients were followed up for 9 months to 4 years without complications such as eye movement disorder or blindness, except for 1 case with preoperatively proptosis occurred postoperatively transient diplopia. There was no recurrence in 6 patients with total lesion removal, and the patient underwent subtotal removal of fibroma did not undertake operation again.@*Conclusion@#Transnasal endoscopic operation for retrobulbar lesions is a minimally invasive, safe and effective operatiiv method, which could be taken via different surgical approaches according to the size and location of the lesion.

"Nitrate stimulating effect" in Amycolatopsis mediterranei--from discovery to mechanistic studies / 生物工程学报

Nitrate not only remarkably stimulates the rifamycinbiosynthesis in Amycolatopsis mediterranei, but also influences the primary metabolisms, including the inhibition of fatty acids biosynthesis in the bacterial. This phenomenon has been designated as "Nitrate Stimulating Effect" by the late Prof. J.S. Chiaosince its discovery in the 1970's, and has been found in many other antibiotics-producing actinomycetes subsequently. Based on the research in his laboratory, we have revealed that the nitrate stimulation effect mainly manifests in two aspects over the last two decades. First, nitrate promotes the supply of rifamycin precursors, e.g., UDP-glucose, AHBA, malonyl-CoA and methylmalonyl-CoA. Specifically, the biosynthesis of fatty acids is inhibited by nitrate consequently the acetyl-CoA is shunted into malonyl-CoA. Second, nitrate facilitates the expression of genes in the rifclulsterthat encodes rifamycin biosynthetic enzymes. Following our current understanding, the future research will focus on the signals, the signal transduction pathway and the molecular mechanisms that dictate nitrate-mediated transcriptional and post-translational regulations.

Combined middle meatus and expand prelacrimal recess-maxillary ainus approach for orbital fracture treatment / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To study surgical techniques and clinical applications of the intranasal endoscopic combined middle meatus and expand prelacrimal recess-maxillary ainus approach for orbital fracture treatment.@*METHOD@#A retrospective clinical analysis of 3 patients whose admitted for orbital floor fractures or medial wall fractures operated by the intranasal endoscopic middle meatus with expand prelacrimal recess-maxillary ainus approach surgical treatment was studied, and the treatment effects and the postoperative complications were analyzed.@*RESULT@#All patients had been followed up for 6 to 12 months. All cases of diplopia symptom were disappeared, enophthalmos were totally corrected, no cases of complication were found.@*CONCLUSION@#Endonasal endoscopic combined middle meatus and expand prelacrimal recess-maxillary ainus approach for orbital fracture treatment have great and clear view. This approach with less tissue damage and high therapeutic effect makes the cost lower than other methods and complications will be decreased as well, it has a great advantage in the orbital fracture treatment.

A case of repeated unconsciousness caused by excrescence locking bicuspid aortic valve / 中南大学学报(医学版)

We received a patient who repeated unconsciousness due to excrescence locking bicuspid aortic valve. He experienced unconsciousness and treatments with anti infection, surgical operation, valve replacement and recovery. It was a rare case, which made us realize that the heart color Doppler ultrasound should be regularly performed in patients with aortic valve abnormalities. Once patients were found to have infective endocarditis combined with the valve vegetations, they should be formally treated as soon as possible.

Imaging classification for horizontal segment of uncinate process and its guiding significance in functional endoscopic sinus surgery / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To explore a new method for horizontal segment of uncinate process classification from image of nasal sinus.</p><p><b>METHODS</b>On the level of horizontal segment of uncinate process of nasal sinus high resolution CT (HRCT) coronal scan. A vertical line and a parallel line were drawn started from the fornix top of the inferior meatus and orbital floor. The uncinate process which suited in the 'Cross' regional was divided into four types by these lines. These were: intra-superior, intra-inferior and extra-superior, extra-inferior. According to this method, 119 patients with chronic sinusitis which were divided into these four types by the imaging classification for horizontal segment of uncinate process operated by functional endoscopic sinus surgery, and the treatment effects and the postoperative complications were analyzed.</p><p><b>RESULTS</b>These 119 chronic sinusitis patients (238 sides uncinated process) were divided into four types by the imaging classification for uncinated process. The amount of intra-superior types was 66.0% (157/238), the amount of intra-inferior types was 16.8% (40/238), the amount of extra-superior types was 13.9% (33/238), and the amount of extra-inferior types was 3.4% (8/238). Functional endoscopic sinus surgery was performed according to this classification. All maxillary sinus natural ostium were found. Two cases occured orbital board damage (one was intra-superior, the other was extra-inferior).</p><p><b>CONCLUSION</b>The imaging classification for horizontal segment of uncinate process demonstrates a guiding significance for us to predict the difficulty of the operation and prevent the complications.</p>

Construction of nasopharyngeal carcinoma CNE-2 cell lines expressing stable fusion suicide gene CD/UPRT. UL49 / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To construct nasopharyngeal carcinoma CNE-2 cell lines expressing stable fusion suicide gene CD/UPRT. UL49.@*METHOD@#The plasmids of pcDNA3.1 (-)E6. BARF1p. CD/UPRT. UL49 was transfected into CNE-2 cells through lipofectamine, and the transfected CNE-2 cells were selected by G418 and prodrugs for getting the cells expressing fusion CD/UPRT. UL49 gene. The protein produced by the suicide gene was tested by Western-blotting in CNE-2 cells.@*RESULT@#Suicide genes were expressed stably in CNE-2 cells.@*CONCLUSION@#We constructed nasopharyngeal carcinoma cell lines CNE-2 expressing stable suicide gene through lipofectamine.

The clinical significance of detecting peripheral blood natural killer cell in the unexplained recurrent spontaneous abortion / 中国综合临床

Objective To investigate the change of peripheral blooe natural killer(NK)cell subsets of patients with recurrent spontaneous abortion( RSA),in oreer to proviee the relevant scientific evieence for unexplainee recurrent spontaneous abortion( URSA) eiagnosis ane treatment. Methods Sixty-three RSA patients were raneomly eivieee into CRSA(n = 33)ane URSA(n = 30). Meanwhile 30 cases normal pregnancy women were selectee as control. Flow cytometry was appliee to eetect NK cell levels in patients with RSA ane its subsets percentage,ane then comparee to the control group. Results NK cells subset in RSA,URAS ane normal pregnancy women were(13. 77 ± 1. 53)% ,(13. 97 ± 1. 60)% ,ane(13. 65 ± 1. 74)%. There was no significant eifference among three groups( F = 0. 287,P > 0. 05). The percent of CD56 + CD16 - ,CD56 +CD16 + ,CD56 - CD16 + NK cell subsets in RAS group were:(70. 00 ± 2. 49)% ,(13. 76 ± 2. 13)% ,(7. 04 ± 1. 44)% respectively,ane(56. 50 ± 3. 94)% ,(22. 88 ± 3. 22)% ,(11. 24 ± 2. 21)% in URAS group, meanwhile(70. 48 ± 3. 21)% ,(14. 16 ± 2. 14)% ,(6. 53 ± 1. 98)% in normal pregnancy group. There was no significant eifference between RSA ane normal pregnancy group( P > 0. 05). However,There was markeely eifference between URSA with RSA or normal group(F = 182. 587,18. 118,58. 879,P < 0. 05). Conclusion NK cell activity function plays a key role in the eevelopment of URSA. The eetection of the percentage of NK cell subsets of women euring pregnancy will help RSA monitoring ane NK cell subsets can preeict the percentage change in the pregnancy outcome .

The predictive value of coronary heart disease (CHD) risk factors in coronary atherosclerosis heart disease / 中国医师杂志

Objective To investigate the predictive value of cardiovascular risk factors in coronary atherosclerotic heart disease.Methods A total of 400 patients who underwent coronary angiography (CAG) in our hospital was divided into multiple vascular lesion group,single vascular lesions group,and non-CAD group according to the result of CAG and their clinical data were analyzed retrospectively.The correlation between cardiovascular risk factors and coronary artery lesions was analyzed,and the independent risk factor of CAD was screened by multi-factorial logistic regression analysis.Results There was significant difference in total cholesterol (TC),triglycerides (TG),high density lipoprotein cholesterol (HDLC),fasting blood glucose (FBG),inflammatory cells,carotid artery plaque,brachial-ankle pulse wave velocity (baPWV),high-sensitivity C-reactive protein (Hs-CRP) between the CAD group and the non-CAD group (P ＜ 0.05 or P ＜ 0.01).The number of coronary artery lesion branch was increased significantly when risk factors,such as age,body mass index(BMI),hypertension,diabetes mellitas,smoking,carotid artery plaque,TG,TC,low density lipoprotein cholesterol (LDL-C),FBG,WBC,monocytes (M),neutrophils (N),neutrophils/lymphocytes (N/L),baPWV,and Hs-CRP.Other risk factors including TC,HDL-C,L were decreased with a statistically significant difference (P ＜ 0.05).There was no significant relation among,and left ventricular ejection fraction (LVEF)％.The most significant risk factor was carotid artery plaque that was independently associated with coronary heart disease (b =1.264,P ＜ 0.01),followed by smoking (b =1.204,P ＜0.01),HDL-C (b =1.104,P ＜0.01),TC (b =1.082,P ＜0.01) diabetes mellitus (b =0.956,P ＜0.01),baPWV increased (b =0.741,P ＜0.01),WBC (b=0.721,P ＜0.01),hypertension (b =0.602,P ＜0.01),the age (b =0.538,P ＜0.01),and HsCRP(b =0.421,P ＜ 0.01).Conclusions The results suggest that the hypertension,hyperlipidemia,smoking,age,baPWV,inflammatory cells,Hs-CRP,and carotid artery plaque was a significant independent CHD risk factors.

The effect analysis of 42 cases of laparoscopic myomectomy / 中国基层医药

Objective To explore the clinical effect of laparoscopic myomectomy.Methods According to the digital table method,75 myoma patients were divided into the study group (42 cases received laparoscopic myomectomy) and the control group(33 cases received transabdonmial myomectomy).The operation time,the time of intestinal function recovery,the amount of bleeding and the postoperative hospital stay time of the two groups were recorded and compared.Results The amount of bleeding,the time of intestinal function recovery and the postoperative hospital stay time of the study group were (111.50 ± 19.38) ml,(17.76 ± 3.64),(4.95 ± 0.54) d,respectively,which were significantly less than those of the control group [(131.15 ± 27.85) ml,(31.64 ± 5.70) h,(7.12± 1.08)d] (t =3.60,12.81,11.35,all P ＜ 0.01).Conclusion Laparoscopic myomectomy has the advantages of less trauma,quicker recovery,shorter hospitalization time etc,so it is worthy of promotion and application in clinic.

Perspective on the novel methods for DNA assembly / 生物工程学报

In 2010, the artificial synthesis of Mycoplasma mycoides triggers the new era of synthetic biology. This great breakthrough is achieved mainly thanks to the powerful DNA recombinant ability of yeast. In recent years, except for the methods used for large DNA assembly on the basis of in vivo homologous recombination, various different DNA assembly methods in vitro, based on the concept of DNA ligation or polymerization, have also been developed, such as Biobrick\BglBrick, SLIC and Gibson one-step assembly. Application of these new technologies has greatly accelerated the construction of synthetic part libraries, biosynthetic pathway and even microbial chromosomes. In fact, all DNA assembly methods are derived from the combinations of DNA joining and organizational schemes. This review describes the brief introduction of the main in vivo and in vitro DNA assembly protocols developed so for, which will benefit the construction of different types of synthetic functional devices and also biosynthetic pathways in the research of synthetic biology in China.

Development in molecular genetic manipulation of solventogenic clostridia / 生物工程学报

Solventogenic clostridia are important industrial microorganisms. Optimization of the fermentation performance of solventogenic clostridia, through genetic modification, has always been considered as the main topic involved in solvents production. However, due to the incomplete genetic tools, no research breakthroughs have been achieved. In recent years, with the development of new technologies and methods (e.g. TargeTron gene knockout, large DNA fragment integration method), great progresses have been made towards genetic engineering solventogenic clostridia. In this review, we summarize the development of the genetic tools for solventogenic clostridial species, and simultaneously point out the shortages of the existing technologies in efficiency and comprehensiveness. Therefore, optimization of the existing technologies in gene inactivation in clostridia, such as establishing homologous exchange-based gene deletion and exchange, is still imperative; and in parallel, new genetic tools (e.g. multiplex genome editing, targeted or random multi-copy gene integration) should also be timely developed.

Impact of renal denervation on expression of renalase and tyrosine hydroxylase in adult rats with spontaneous hypertension / 中南大学学报(医学版)

OBJECTIVE@#To investigate the impact of renal denervation on the blood pressure, plasma renalase content and expression of renalase and tyrosine hydroxylase (TH) in the idney of spontaneous hypertensive (SH) rats and to explore the role of renal denervation in lowering the blood pressure.@*METHODS@#SH rats were randomly assigned into a baseline group, a surgery (renal denervation) group, a sham group and a control group (n=48). WKY rats matched in age (n=12) served as a baseline control group. All rats were housed until 12 weeks old. Then, the rats in the baseline group and the WKY group were sacrificed whose blood and kidney were collected for examination. In the renal denervation group, the sham group and the control group, the blood pressure was monitored continuously. One week and 6 weeks after the renal denervation, 6 rats in each group were sacrificed whose blood and kidney were collected. ELISA was employed to measure the plasma renalase and Western blot assay done to detect the expression of TH and renalase in the kidney.@*RESULTS@#Compared with WKY rats, blood pressure significantly increased and TH protein expression markedly elevated (P0.05). No pronounced differences in the above variables were found between the sham group and the control group at any time point (P>0.05).@*CONCLUSION@#Renal denervation can lower the blood pressure, which may attribute to the suppression of sympathetic nerves, increase in plasma renalase content and renalase expression in the kidney.

Research progress with renalase and cardiovascular disease / 中南大学学报(医学版)

Renalase, a novel amine oxidase, is secreted by kidney. It regulates heart function and blood pressure by degrading catecholamines. Hormones secreted by the kidney are associated with cardiovascular disease. Renalase, as a new biomarker of heart and kidney functional correlation, can lower blood pressure, protect ischemic heart muscle, improve heart function and degrade catecholamine.

Epidemiological status and risk factors for hypertensive disorder complicating pregnancy in a district in Changsha / 中南大学学报(医学版)

OBJECTIVE@#To comprehend the epidemiological status and risk factors in hypertensive disorder complicating pregnancy (HDCP) in a district in Changsha, and to provide epidemiological evidence for early intervention of HDCP.@*METHODS@#A total of 2 148 pregnant women in a district in Changsha from 2008 to 2009 were retrospectively analyzed and the related factors were evaluated by multivariate unconditional logistic analysis.@*RESULTS@#The incidence of HDCP was 5.21% from 2008 to 2009. Multivariate unconditional logistic regression analysis showed that age (>35 years old)(OR=6.440,95%CI:2.987-13.884), body mass index (BMI) before pregnancy (OR=2.180,95%CI:1.619-2.936), and history of diabetes or kidney disease (OR=14.221,95%CI: 3.990-50.684) were risk factors for HDCP.@*CONCLUSION@#Age, BMI before pregnancy, and history of diabetes or kidney disease are risk factors for HDCP, while gravidity, parity, number of abortion and multiple gestation pregnancy have no obvious correlation with HDCP.

Prevalence of allergens for Changsha patients with allergic rhinitis / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To investigate the allergens in patients with allergic rhinitis, to find common allergens of Changsha and to provide statistic basis for a reasonable prevention and treatment.@*METHOD@#The allergens in 1437 patients with allergic rhinitis in Changsha were detected by skin prick test.@*RESULT@#Eight hundred and ninety-eight (62.49%)of 1437 cases presented positive reaction. Among positive cases in inhalation group, the most common allergen was flour mite (98.33%), then were house dust mite (94.54%), mycetes II (19.27%) and weed (18.37%). Shrimp (35.41%) was the most common allergens in food group. And in childhood, adolescence and adulthood prick-positive cases, the ratio of more than 2 positive allergens were about 8.57%,18.04%, 19.15%.@*CONCLUSION@#The study shows that the flour mite and house dust mite are the most common allergens in Changsha.

Effect of pregnancy-associated plasma protein-A on the function of endothelial cells / 中南大学学报(医学版)

OBJECTIVE@#To determine the effect of pregnancy-associated plasma protein A (PAPP-A) on the function of vascular endothelial cells (VEC).@*METHODS@#Human umbilical vein endothelial cell (HUVEC) line, derived from human umbilical vein, was cultured in vitro with PAPP-A at 0, 50, 100, and 200 ng/mL for 0, 12, 24, and 48 hours, respectively. Nitric oxide (NO) levels and endothlin-1 (ET-1) levels were determined by spectrophotometer and immunehistory.@*RESULTS@#The NO levels of HUVECs in the PAPP-A groups were significantly lower than those in the control group (P<0.05). The ET-1 levels of HUVECs in the PAPP-A groups were significantly higher than those in the control group (P<0.05). The changes were all dose-dependent.@*CONCLUSION@#PAPP-A may affect the function of vascular endothelial cells by reducing the secretion of NO and increasing the level of ET-1.