One of the technical bottlenecks limiting the high yield of 1,4-butanediamine is the insufficient tolerance of strains to 1,4-butanediamine. Enhancing the tolerance of strains to 1,4-butanediamine is therefore a primary challenge that needs to be addressed for the construction of strains with high yields of 1,4-butanediamine. Staphylococcus pasteuri 326180 exhibits exceptional tolerance to high-concentration 1,4-butanediamine, serving as both an ideal model for studying the mechanism underlying the 1,4-butanediamine tolerance and a novel host for constructing strains capable of efficiently producing 1,4-butanediamine. However, for both the research on the tolerance mechanism and the modification of chassis strains, gene editing of S. pasteuri needs to be carried out at the molecular level. The research objective of this paper is to establish a genetic manipulation system for S. pasteuri, laying foundation for subsequent studies on tolerance mechanism and the modification of chassis strains. This study systematically optimized the electroporation conditions, including key parameters such as the growth phase of cells, electric field strength, electroporation buffer, and recovery medium, successfully establishing an electroporation method for S. pasteuri. Additionally, we constructed the gene editing plasmid pCpfOA by replacing the resistance expression cassette, optimized the selection markers for gene editing, and finally established a CRISPR/Cpf1-based gene editing technology for S. pasteuri, achieving an editing efficiency of 90%. The genetic manipulation system of S. pasteuri established in this study provides technical support for research into the tolerance mechanism of this bacterium and the genetic modification of chassis strains.
Staphylococcus/drug effects* ; Gene Editing/methods* ; Electroporation/methods* ; Plasmids/genetics* ; CRISPR-Cas Systems ; Genetic Engineering/methods*

Objective: To understand lunch satisfaction and leftovers of Changsha compulsory education schools under different supply modes served by school canteens and specialized enterprises,and to provide scientific basis for the government to formulate school lunch improvement policies. Methods: Multistage stratified cluster sampling method was used to random select 2 203 students from 8 primary and secondary schools in Changsha who were administered with questionnair survey in April to May of 2018. Results: For school lunch, the overall rate of satisfaction was 78.8%.The overall lunch satisfaction of female and primany school students were higher than that of male and junior high school students respectively,and the difference was statistically significant(P<0.05). Totally 76.0% of students had the highest satisfaction in food hygiene and the lowest satisfaction rate was 60.0% in food taste. By comparing different supply modes, the overall satisfaction rate of meal quantity was higher (47.8%) under school canteens, and that of dining environment was relatively high (43.7%) under specialized enterprises. "Don-t like some food" (63.8%) was the main reason for students leftovers under the two supply modes. The lunch leftover rate of specialized enterprises (37.8%) was significantly higher than that of school cafeteria (30.6%)(χ 2=12.81，P<0.05). Conclusion The satisfaction of food taste and the rate of lunch leftovers need to be further improved. School canteens environment and management should be strengthened, as well as the flexibility and communication under specialized enterprises and family-school communication. The joint efforts by school and family are needed for healthy eating education.

Objective:To investigate the role and mechanism of Nod-like receptor protein 3 (NLRP3) in chronic kidney disease (CKD)-related neointimal hyperplasia (NH) of vessels.Methods:Wild type C57BL/6J male mice were randomly divided into normal control group ( n=6) and experimental group ( n=18), by removal of 5/6 kidney and ligation of left common carotid artery to establish a NH model. After established successfully, the mice in NH experimental group were randomly divided into NH model group, NLRP3 inhibitor group, and drug control group ( n=6/group). C57BL/6J male mice with NLRP3 gene knockout group did not do any treatment after the establishment of NH model. After 3 weeks of feeding, the blood and vascular tissue samples of mice were collected. The pathological changes of vascular tissue samples in mice were observed by hematoxylin-eosin staining. The expressions and localization of NLRP3-related protein were observed by immunofluorescence staining. The expression of NLRP3 mRNA in vascular tissue was detected by quantitative real-time PCR. The activity of caspase-1 in vascular tissue was measured by colorimetric method. Human aortic smooth muscle cells (HASMCs) were treated with 10% uremic serum to simulate the body's internal environment during the uremic phase. NLRP3 small interfering RNA (siRNA) was transfected or NLRP3 inhibitor glibenclamide was added to the cell cultures. The expression of NLRP3 mRNA in HASMCs was detected by quantitative real-time PCR. The activity of caspase-1 in HASMCs was detected by colorimetric method. Results:Compared with the control group, the levels of serum creatinine and blood urea nitrogen were significantly increased in the NH model group (both P<0.01). The vascular histopathology showed that vascular intima thickened, vascular smooth muscle cells proliferated and hypertrophied, nuclei were deeply stained, and cells arranged disorderly and migrated to vascular intima in the experimental group. Quantitative analysis showed that the ratio of neointima to lumen increased significantly in the NH model group than that in control group ( P<0.01). Compared with the control group, the immunofluorescence staining of vascular tissue showed that the expressions of NLRP3, caspase-1, IL-18, IL-1β and proliferating cell nuclear antigen (PCNA) protein in the NH model group increased (all P<0.01), while the expression of α-SMA decreased ( P<0.01). NLRP3 was mainly located in vascular smooth muscle cells (VSMCs). VSMCs showed a synthetic phenotype. Compared with the NH model group, the expression of NLRP3, caspase-1, IL-18, IL-1β and PCNA protein in the NLRP3 inhibitor group and NLRP3 gene knockout group decreased (all P<0.01), the expression of α-SMA increased ( P<0.01), and the pathological changes of blood vessels alleviated. Compared with healthy serum group, the expression of NLRP3, IL-18, and IL-1β and bromodeoxyuridine (BrdU) uptake in uremic serum-stimulated group were increased (all P<0.01). After transfection of NLRP3 siRNA and addition of glibenclamide, the expression of NLRP3, IL-18, and IL-1β in VSMCs in uremic serum-stimulated group decreased, and BrdU intake decreased (all P<0.01). Conclusions:NLRP3 inflammatory bodies play an important role in promoting CKD-related neointimal hyperplasia of vessels, and glibenclamide can effectively reduce neointimal hyperplasia.

Talaromyces Marneffei infection is rarely reported in patients with chronic active Epstein-Barr virus (EBV) infection. We reported an old man with chronic fever, pleomorphic rash, cough, EBV viraemia, and secondary hemophagocytic syndrome. Repeated histological biopsy and culture of skin lesions revealed Talaromyces Marneffei. This patient was diagnosed as chronic active EBV infection, and Talaromyces Marneffei infection. After treated with glucocorticoid steroids and anti-fungal therapy, the patient finally recovered. EBV infection is usually seen in immune compromised patients, who are susceptible to opportunistic pathogens rarely as Talaromyces Marneffei in this case.

Hydroxy amino acids, constituents of chiral pharmaceutical intermediates or precursors, have a variety of unique functions in the research fields of biotechnology and molecular biology, i.e. antifungal, antibacterial, antiviral and anticancer properties. Biosynthesis of hydroxy amino acids is preferred because of its high specificity and selectivity. The hydroxylation of hydrophobic amino acids is catalyzed by hydroxylase, which belongs to the mononuclear non-heme Fe(Ⅱ)/α-ketoglutarate-dependent dioxygenases (Fe/αKGDs). Fe/αKGDs utilize an (Fe(Ⅳ)=O) intermediate to activate diverse oxidative transformations with key biological roles in the process of catalytic reaction. Here, we review the physiological properties and synthesis of hydroxy amino acids, especially for the 4-HIL and hydroxyproline. The catalytic mechanism of Fe/αKGDs is elucidated, and the applications of hydroxy amino acids in industrial engineering are also discussed.

Objective To summarize the clinical characteristics of SLE patients complicated with Listeria monocytogenes meningitis (LMM).Methods The clinical manifestations,systemic involvements,laboratory tests,cerebrospinal fluid (CSF) examinations,treatment and prognosis of SLE inpatients combined with LMM in Peking Union Medical College Hospital during Janurary 2000 to December 2015 were retrospectively analyzed.Results Eight SLE patients with LMM accounted for 0.14％ of the 5 675 hospitalized SLE patients.Seven were female and 1 was male,with the mean age of (35±16) year.Headache (7/8) was the most common neurological symptom followed by positive meningeal irritation sign (5/8),unconsciousness (3/8) and nausea or vomiting (2/8).Increased intracranial pressure was found in 7 cases and 4 of them were even higher than 330 mmH2O.CSF protein elevated in 6 cases and CSF glucose decreased in 6 cases.LMM often occurred in inactive or mild active SLE with the average SLE disease activity index (SLEDAI) score of 4.7±1.5.Systemic manifestations included hematologic changes (6/8),rashes (4/8),renal involvement (4/8) and arthritis (3/8),etc.Treated by autibiotics such as penicillin and medications for SLE,7 patients achieved clinical improvements,1 patient died.Conclusion LMM is one of the opportunistic infections in SLE patients and tends to occur in inactive lupus cases.There are unspecific clinical and laboratory features and CSF changes which maybe overlap and mix up with systemic manifestations of SLE.That's why it is necessary to take continuous cultures of CSF.Early identification and appropriate treatment lead to prognostic improvement of these patients.

Objective To compare the short-term therapeutic effect, adverse reaction and influence on immune function between chrono-chemotherapy and routine-chemotherapy with docetaxel +cisplatin(DP)combined with concurrent chemoradiotherapy with cisplatin(DDP)in locally advanced(Ⅲ,Ⅳa stage)nasopharyngeal carcinoma(NPC).Methods 70 cases of newly diagnosed locally advanced NPC were randomly divided into group A and group B,35 cases in each group.Two groups of patients were treated with two cycles of neoadjuvant chemotherapy with DP combined with concurrent chemoradiotherapy with DDP.Both nereoadjuvant chemotherapy and concurrent chemotherapy of patients in group A were administrated with chrono-chemotherapy.Both nereoadjuvant chemotherapy and concurrent chemotherapy of patients in group B were administrated with routine-chemotherapy.Therapeutic effect,adverse reactions and other indicators were observed in both groups.Results After 3 months,there was no sifnificant difference of short term total efficacy between two groups in nasopharyngeal primary tumor(35 cases vs.34 cases),cervical lymph node(32 cases vs.31 cases).The incidence of adverse reactions of marrow toxicity(WBC,Hb,PLT)in group A was lower than group B(P<0.05),the incidence of digestive tract(nausea and vomiting,diarrhea)in group A was lower than group B(P<0.05),while there was no significant difference in oral mucositis between two groups(P<0.05).The high creatinine incidence in group A was lower than group B(P<0.05).There was no significant difference in high blood urea nitrogen and high transaminase incidences between two groups.After treatment, the T lymphocytes ( CD3 +, CD4 +, CD8 +, CD4 +/CD8 +) had no change in group A,the T lymphocytes(CD3 +,CD4 +)in group B decreased significantly compared with pre-treatment(P<0.05),and were lower than group A(P<0.05).Conclusion Adverse reactions and the degree of decline in cellular immune function of chrono-chemotherapy are lower than routine-chemotherapy in locally advanced NPC.

Brown-Sequard Syndrome ; diagnosis ; Diagnosis, Differential ; HIV Infections ; complications ; Humans ; Male ; Middle Aged ; Mycobacterium avium-intracellulare Infection ; diagnosis

The clinical features and lung CT findings of 174 heart failure patients,including 85 cases with normal left ventricular ejection fraction (LVEF) and 89 cases with reduced LVEF were reviewed.Patients with normal LVEF had a higher proportion of hypertension,diabetes and obesity than patients with normal LVEF; and cough and dyspnea were more common.The lung CT findings in patients with normal LVEF were frequently presented as interstitial lung edema,increased pulmonary texture,subpleural line,Kerley lines and diffuse ground-glass opacity.Patients with reduced LVEF had a higher proportion of coronary heart disease and clinical manifestations of acute left heart failure,and central alveolar edema presented in lung CT images.Results suggest that heart failure patients with normal LVEF usually have longer clinical history and occult symptoms,and have a different lung CT imaging features from those in heart failure patients with reduced LVEF.