Heme, which exists widely in living organisms, is a porphyrin compound with a variety of physiological functions. Bacillus amyloliquefaciens is an important industrial strain with the characteristics of easy cultivation and strong ability for expression and secretion of proteins. In order to screen the optimal starting strain for heme synthesis, the laboratory preserved strains were screened with and without addition of 5-aminolevulinic acid (ALA). There was no significant difference in the heme production of strains BA, BAΔ6 and BAΔ6ΔsigF. However, upon addition of ALA, the heme titer and specific heme production of strain BAΔ6ΔsigF were the highest, reaching 200.77 μmol/L and 615.70 μmol/(L·g DCW), respectively. Subsequently, the hemX gene (encoding the cytochrome assembly protein HemX) of strain BAΔ6ΔsigF was knocked out to explore its role in heme synthesis. It was found that the fermentation broth of the knockout strain turned red, while the growth was not significantly affected. The highest ALA concentration in flask fermentation reached 82.13 mg/L at 12 h, which was slightly higher than that of the control 75.11 mg/L. When ALA was not added, the heme titer and specific heme production were 1.99 times and 1.45 times that of the control, respectively. After adding ALA, the heme titer and specific heme production were 2.08 times and 1.72 times higher than that of the control, respectively. Real-time quantitative fluorescent PCR showed that the expressions of hemA, hemL, hemB, hemC, hemD, and hemQ genes at transcription level were up-regulated. We demonstrated that deletion of hemX gene can improve the production of heme, which may facilitate future development of heme-producing strain.
Gene Deletion ; Bacillus amyloliquefaciens/metabolism* ; Aminolevulinic Acid/metabolism* ; Heme/metabolism* ; Fermentation

To analyze the clinical characteristics of patients with antisynthetase syndrome (ASS) and positive anti-Ro52 antibody. The clinical data of 203 ASS patients admitted to the First Affiliated Hospital of Zhengzhou University from 2017 to 2020 were analyzed retrospectively. Demographics, clinical manifestations, laboratory results, treatment and outcome were collected including data of 18 patients with rapidly progressive interstitial lung disease (RP-ILD). In total, the majority were women (148,72.9%). The average onset age was (51.9±13.3) years. There were 163 (80.3%) patients with positive anti-Ro52 antibody. The positivity in women (77.3% vs. 55.0%, P=0.004) was higher, and the median time from disease onset to diagnosis [4.5 (2.0, 24.0) months vs. 2.0 (1.0, 12.0) months, P=0.024] was longer in patients with positive anti-Ro52 antibody than those negative. Compared with negative patients, patients with positive anti-Ro52 antibody had a higher incidence of interstitial lung disease (ILD) (96.9% vs. 65.0%, P<0.001), arthritis (33.7% vs. 17.5%, P=0.046), and arthralgia (39.3% vs. 20.0%, P=0.022). Higher rate of positve antinuclear antibody (ANA) (85.3% vs. 55.0%, P<0.001), lower rate of positive anti-Jo-1 antibody (32.5% vs. 50.0%, P=0.039), lower albumin level [(34.6±5.2) g/L vs. (37.3±4.7) g/L, P=0.004] and lower lymphocyte counts [(1.4±0.8) ×10 9/L vs. (1.8±0.8) ×10 9/L, P=0.014] were more common in patients with positive anti-Ro52 antibody. The presence of anti-Ro52 antibody is associated with a particular phenotype of ASS, leading to common ILD, involvement of joints, high ANA positivity, low albumin and low lymphocyte counts.

To investigate the clinical manifestations and imaging characteristics of patients with different types of infectious sacroiliitis. Clinical data of 40 patients diagnosed with infectious sacroiliitis were retrospectively analyzed. Among the 40 patients, 16 patients were diagnosed as non-brucellar and non-tuberculous infectious sacroiliitis (ISI), 13 with tuberculous infectious sacroiliitis (TSI), and 11 with brucellar sacroiliitis (BSI). In the ISI and TSI group, female patients accounted for 11/16, 12/13, while the proportion of unilateral involvement was 15/16 and 12/13, respectively. Compared with ISI and TSI group, BSI patients were mainly male (8/11) and presented more bilateral involvement (6/11) ( P<0.05). Bone erosion was more common in ISI and TSI groups than in BSI group (6/15, 7/11 and 2/10), as well as abscess formation (3/15, 4/11 and 1/10, respectively). Symptoms in all patients relieved 1-2 weeks after administration of antibiotics or anti-tuberculosis treatment, but the resolution of the magnetic resonance imaging findings delayed about 6 (3-9) months. ISI and TSI patients with infectious sacroiliitis should be differentiated from spondyloarthritis, with a characteristic of more female patients, unilateral sacroiliitis, bone erosion, soft tissue involvement and abscess formation. However, BSI patients are mainly male, more bilateral involvement and less bone destruction and abscess formation. Antibiotic therapy demonstrates significant therapeutic effects, but resolution of the magnetic resonance imaging findings responses late.

Objective To investigate the clinical and epidemiological characteristics of 135 confirmed cases of COVID-19 in Tianjin. Methods The clinical and epidemiological data of 135 cases of COVID-19 in Tianjin were collected, and the data were analyzed with descriptive method. The factors influencing the severity of the illness were analyzed. Results Among the 135 COVID-19 cases, 72 were males and 63 were females, the age of the cases was (48.62±16.83) years, and the case fatality rate was 2.22%. Local transmission caused 74.81% of the cases. A total of 33 clusters occurred, involving 85.92% of all COVID-19 cases. The median of the incubation period of COVID-19 was 6.50 days, the average generation interval was 5 days, and the household secondary transmission rate was 20.46%. Fever was the main symptom (78.63%), followed by cough (56.48%). Multivariate regression analysis indicated that age ( OR =1.038, 95% CI : 1.010-1.167) and the number of chronic underlying diseases ( OR =1.709, 95% CI : 1.052-2.777) were the risk factors of severe illness. Conclusions Fever was the main symptom at the early phase of COVID-19 in Tianjin, and the local cluster cases accounted for high proportion in confirmed COVID-19 cases reported in Tianjin. Severe illness was prone to occur in people with old age and multi underlying diseases. Strict isolation of close contacts and intensive care of high-risk groups are the main measures to reduce the morbidity and case fatality of COVID-19.

Objective To investigate the pathogenic spectrum and epidemiological characteristics of acute diarrhea patients in Tianjin.Methods A total of 1 536 stool samples of diarrhea patients were collected from hospitals between 2015 and 2017.Viral nucleic acids were detected by real-time polymerase chain reaction.Selective medium was used to culture bacteria.Drug susceptibility tests were performed by Kirby-Bauer disk diffusion method recommended by the Association for Standardization of Clinical Laboratories.x2 test was used for statistical analysis.Results In the stool samples of 1 536 cases of diarrhea,one enteric bacterium was detected in 109 samples with the positive rate of 7.10％,one enterovirus was detected in 171 samples with the positive rate of 11.13％,mixed infection was detected in 20 samples with positive rate of 1.30％,including 8 samples with enteric bacterium and enterovirus and 12 samples with double enterovirus.The total detection rate of diarrhea cases was 19.53％.Norovirus,vibrio parahaemolyticus,rotavirus,Salmonella,stellate virus and sapovirus ranked the top six in the detection rate.The total detection rate curve of bacteria showed a single peak,mainly in August,while the total detection rate curve of the virus showed a double peak,which was from May to June and from November to December.The positive rate of bacteria in patients aged over 30 years old was 9.82％ (75/764),while that in those aged less than 30 years old was 5.44％ (42/772).The difference was statistically significant (x2 =10.451,P ＜ 0.01).The positive rate of viral pathogen in patients aged no less than 25 years old was 10.02％ (91/908),while that in those aged less than 25 years old was 17.83％ (112/628).The difference was statistically significant (x2 =19.755,P ＜ 0.01).Salmonella,Shigella and vibrio parahaemolyticus were resistant to ampicillin in varying degrees.Conclusions The positive rate curves of bacteria and virus are obviously different,showing a trend of "bacterial single peak and viral double peak".Bacteria mainly infect people aged over 30 years old,while the virus mainly infects people under 25 years old.The main pathogens of diarrhea are norovirus,vibrio parahaemolyticus and rotavirus.

Objective To evaluate the guidance value of VKORC1 and CYP2C9 gene polymorphism on clinical application of warfarin in patients with non-valvular atrial fibrillation (NVAF). Methods A total of 290 cases of patients with NVAF were identified and their baseline data , initial dose of warfarin and base INR measurement results were recorded, then the follow-up was conducted. The initial administration of warfarin to INR standard time for the first time, total amount of warfarin and the average daily amount were recorded. All participants′ venous blood was extracted for VKORC1 and CYP2C9 gene polymorphism test. Results VKORC1 AG/GG genotype patients had longer INR standard time and higer amount of warfarin than patients with AA (103.38 ± 65.29)g vs. (53.26 ± 24.02)g, P < 0.05. Patients with type CYP2C9 gene mutation had shortest INR standard time(9.10 ± 2.01)d vs. (13.07 ± 4.28)d, P < 0.05. and lowest administration amount of warfarin (28.80 ± 17.35)g vs. (55.45 ± 23.67)g, P < 0.05. Conclusion There exist significant differences of first adminstration amount of warfarin in patients with NVAF to INR standards. Warfarin dose for VKORC1 AA genotype patients is lower than that for GG/AG type; there is short INR standard time and less adminstration amount of warfarin for CYP2C9 genotypes AC/CC patients.

Objective To investigate the application of statins in secondary prevention of ischemic stroke and transient ischemic attacks (TIA) in different risk groups,and to identify the factors influencing the compliance of statins. Methods Data were prospectively collected on consecutively encountered ischemic stroke or TIA patients admitted to the First Affiliated Hospital of Zhengzhou University from April 2009 to January 2010.All clinical characteristics and possible factors influencing the compliance of statins were collected; the application of statins was investigated at 3-month follow-up.The multivariate Logistic regression analysis was used for the analysis of influence factors of the compliance of statins.Results All 369 patients were collected,52.8％ of cases were prescribed statins for therapy during hospitalization.The application rate of statins in accordance with guidelines in high-risk group,extremely high-risk Ⅱ group and extremely high-risk Ⅰ group was 25.0％ (16/64),44.1％ (30/68) and 71.4％ (135/189),respectively. Logistic regression analysis showed that the statins application during hospitalization was associated with diabetes history ( P =0.032,OR =1.789,95％ CI 1.052-3.043 ) and the presence of carotid vulnerable plaques(P =0.000,OR =5.308,95％ CI 3.340-8.434).The general application rate of statins was 22.3％ (81/363),which was significantly lower than that during hospitalization. The application rate of statins in accordance with guidelines in high-risk group,extremely high-risk Ⅱ group and extremely high-risk Ⅰ group was 9.7％ ( 6/62 ),25.8％ (17/66) and 29.4％ (55/187) respectively.Logistic regression analysis showed that good compliance of statins was associated with discharge instructions on statins application ( P =0.000,OR =34.852,95％ CI 14.673-175.452 ). Conclusions The compliance of statins in secondary prevention of ischemic stroke and TIA is poor,and there is still a large gap between clinical practice and guidelines; Discharge instructions on statins application increase the compliance of statins.

Objective To investigate the predictive value of the modified National Institutes of Health Stroke Scale ( mNIHSS),measured within 9 days after stroke,for the outcome in terms of modified Rankin Scale (mRS) at 6 months after stroke.Methods AII 161 patients with acute anterior circulation ischemic stroke were recruited consecutively from July 2010 until November 2010.The mNIHSS score was assessed within 3 days,4 to 6 days and 7 to 9 days after stroke,and the mRS score at 6 months after stroke was assessed by a neurology resident.Spearman rank correlation and ROC curve were used for statistic analysis.Results One hundred and sixty-one patients were assessed within 3 days,at 4 to 6 days and 7 to 9 days after stroke.Significant Spearman rank correlation coefficients were found between mRS at 6 months and mNIHSS scores within 3 days (rs =0.592,P＜0.01 ),4 to 6 days (rs =0.597,P＜0.01 ) and 7 to 9days (rs =0.595,P＜0.01).At 6 months after stroke,the AUC ranged from 0.789 (95％ CI 0.708-0.856) for measurements within 3 days to 0.792 (95％ CI 0.712-0.857 ) and 0.799 ( 95％ CI 0.721-0.864) for 4 to 6 days and 7 to 9 days,respectively. There was no significant difference for the AUCbetween them.The optimal cut-off values for the prediction of prognosis at 6 months were 8,7 and 6 points of mNIHSS score within 3 days,4 to 6 days and 7 to 9 days,respectively.The negative predictive value gradually increased from 0.847 for assessment within 3 days to 0.867 ( 95％ CI 0.578-0.765 ) for 7 to 9 days,whereas positive predictive value declined from 0.601 for assessment within 3 days to 0.533 for 7 to 9 days.The overall accuracy of predtictions decreased from 0.753 for assessment within 3 days to 0.709 for 7 to 9 days.Conclusions When measured within 9 days,the mNIHSS has a good predictive value for final outcome in terms of mRS at 6 months after stroke.However,the optimal cut-off values for the prediction of prognosis at 6 months are different when early mNIHSS scores were assessed at different periods.

Objective To assess the influence of active movement of the affected upper limb on the prognosis for patients after acute cerebral infarction.Methods From 2007 to 2008, 171 consecutive patients with acute cerebral infarction were registered prospectively in this study. Active movement of the hemiplegic upper limb was assessed on the 14th day after stroke onset. Ability in the activities of daily living was assessed using the Barthel index one year later.Results Finger flexion and extension on the 14th day after stroke onset correlated positively with Barthel index scores 1 year later. NIHSS scores at admission, the time interval from onset to admission and stroke history were significant predictors of the prognosis 1 year later.Conclusion Assessing the active movement of the hemiplegic upper limb on the 14th day after stroke has good predictive power for the prognosis of acute cerebral infarction patients.

Objective To investigate the effect of the side of cerebral lesion on the outcome in patients with ischemic stroke.Methods A total of 407 consecutive anterior circulation ischemic stroke patients within 14 days after symptom onset were recruited prospectively.The basic data ofthe e,~ISes were collected,such as the National Institutes ofHealth Stroke Scale (NU-ISS)and the side ofcerebral lesion.The modified Rankin Scale(mRS)was used to evaluate the prognosis of the patients at 6 raomhs.Results Of the 407 patients recruited,230 patients (56.5%)Were left hemisphere stroke,177(43.5%)were fight hemisphere stroke.After multivariable logistic recession analysis,the age(odds ratio[OR]1.022,95% confidence interval[CI]1.001-1.043,P=0.040),the side of lesion(OR 1.999.95%CI1.179.3.389.P=0.010),the time from onset to admission(OR1.006,95%(7/1.002-1.010,P=0.007),the outcome of the anterior circulation ischcmic stroke at 6 months aftel"onset.The outcome of the right hemisphere stroke Was significantly worse than that of the left hemisphere stroke.The onset-admission time in patients with right hemisphere stroke(median 12 h,median 39.61 h)was significantly delayed compared to the patients with left hemisphere stroke(median 12 h,median 22.72 h;Z=-2.962,P=0.003).Condusions The outcome of the left hemisphere stroke at 6 months after onset is superior to the right hemisphere stroke,and it mau be associated with the delayed admission.