A method of streptomycin resistance screening was applied to improve t he productivity of Natamycin by Streptomyces gilvosporeus(ATCC13326) The sp ores treated with UV light were regenerated on agar plates containing 0 6?g/mL stre p tomycin 122 streptomycin resistant(str) mutants were obtained The Natamycin y iel ds of 13 mutants were higher than the original strain The mutants with high Na t amycin productivity were screened at a high frequency(10 6%) The highest one that demonstrated 1 46 times that of the original strain in Natamy cin productivity was obtained

ObjectiveTo investigate the effect of milk and milk products on morphological structure and epidermal growth factor (EGF) of non-steroidal anti-inflammatory drugs (NSAIDs) induced small intestinal damage in animals.Methods Eighty male SD rats were randomly divided into 5 groups:control group,diclofenac group,diclofenac with 10% low fat milk group,diclofenac with 10% colostrum group and diclofenac with yoghurt group.The animals with milk or colostrum or yoghurt were fed for 5 days before the administration of diclofenac with 15 mg/kg by gavage,once.Then they were observed the scores of anatomical lesion and the scores of tissue damage of mucous membrane and the height of villous at the 24th and 48th hour after making the models.Observation of the change of ultrastructural organization of mucous membrane was carried out with transmission and scanning electron microscope and immunohistocbemistry of EGF.Results The scores of anatomical lesion and tissue damage of mucous membrane of the colostrum group were lower than those of the diclofenac group ( P ＜ 0.05 ).The heights of the pile on small intestine of the24th and 48th hour of the colostrum group were (145.7 ± 16.5) μm and (139.2 ± 19.0) μm,respectively.They were higher than those of the diclofenac group[( 119.2 ± 19.2 ) μm and ( 105.4 ± 18.4 )μm,P ＜ 0.05].However there was no difference of the scores and the height among diclofenac group,milk group and yoghurt group.TEM and SEM of tissues showed that the cytoplasmic membrane and other cellular components of villous epithelial cells were well preserved in colostrum group,and the microvilli in the milk group and yoghurt group were ablated more obviously.The positive area of EGF of small intestine [(6170.5 ± 1483.9) μm2]were higher 48 h after administration of diclofenac compared with the diclofenac group ( P ＜ 0.05 ).The expression of EGF in milk and yoghurt group were no significant statistical difference with the diclofenac group.ConclusionBovine colostrum may have a beneficial effect in prevention of NSAIDs induced small intestinal injuries and preserve mechanical barrier of small intestinal mucosa which is probably relative to EGF.

Objective To explore the clinical features and perioperative treatment effects of colorectal cancer in elderly patients.Methods Retrospective analysis of clinical data especially focusing on perioperative treatment from 104 elderly patients with coloreetal cancer were performed.Results A total of 99 patients (95.2%) were cured or improved at discharge.Perioperative pulmonary infection occurred in 13 cases (12.5%), of whom 6 cases (5.8%) suffered from respiratory failure.Lower extremity deep venous thrombosis occurred in 3 cases (2.9%), incision infection in 6 cases (5.8%), wound dehiscence in 2 cases (1.9%), intestinal fistula in 1 case (1.0%) and gastroparesis in 1 case (1.0%).About 5 cases (4.8%) died from multiple organ failure.Conclusions Old age is not a contraindication in surgical treatment for colorectal cancer.Paying attention to accurate and timely treatment in perioperative peroid can reduce postoperative complications and improve patients' quality of life.

This paper analyzes the characteristics of medical equipment's preventive maintenance, and it expounds the objective and methods of introducing risk management to medical equipment's preventive maintenance,what's more,the problem of establishment object and cycle of preventive maintenance was solved scientifically.
Equipment and Supplies, Hospital ; Maintenance ; Risk Assessment

Objective To explore a new index for reflecting the topological information of brain functional networks in patients at high risk of Alzheimer disease using characteristics of resting-state functional connectivity strengths(FCS) in patients with amnestic mild cognitive impairment(aMCI). Methods Thirty-one aMCI patients and 42 age, gender and years of education matched normal controls were enrolled between September 2009 and April 2011 in this study. The resting-state functional MRI (rs-fMRI) data of all participants were acquired and preprocessed. Then the whole-brain functional connectivities were constructed for exploring the distribution characteristics of hub regions which had higher FCS values. Using two-sample t test to compare group differences in age, years of education and each neuropsychological assessment. In addition, using Chi-squared test to compare group differences in gender. Group differences in FCS values were analyzed by general linear model. Finally, correlation analyses were used to evaluate the relationships between the FCS values of the brain regions with group differences and behavioral scores in aMCI patients. Results The hub regions of the functional networks in the aMCI patients were mainly located in the association cortices such as the precuneuses, posterior cingulate cortices, medial prefrontal cortices, angular gyri, superior occipital gyri, fusiform gyri and lingual gyri. The distribution models in the aMCI patients were consistent with those in the normal controls. However, the FCS values of these brain regions were significantly lower in the aMCI patients than those in the normal controls. In comparison to the normal controls, the aMCI patients had significantly decreased FCS values in the bilateral fusiform gyri, lingual gyri, superior occipital gyri, left middle occipital gyrus and postcentral gyrus (the cluster was 389, 230, 187 and 107 voxels, respectively;P<0.05, respectively), and they had decreased trends of FCS values in the bilateral posterior cingulate cortices and right insulas. The correlation analysis with uncorrected conditions showed that the FCS values of the left postcentral gyri were correlatid with the clock drawing test (CDT) scores (r=0.436, P=0.026). Conclusions aMCI mainly attacks the hub regions of brain functional networks. The changes of functional connectivities in aMCI may reflect the early pathophysiologic alterations of AD.

Objective To identify the clinical features, the molecular diagnosis and the molecular mechanism of three unrelated factor X deficiency families. Methods Three probands were male and the diagnosis was validated by coagulant parameters. The F X coagulation activity ( F X∶ C ) and antigen (FX∶ Ag) were tested by clotting test and ELISA method. The cross-corrected test was used to rule out the inhibitor of FX in plasma. Thrombin generation test was evaluated. The antigen and the molecule weight of the FX in plasma were measured with western blotting. Gene mutations were analyzed in the probands and their family members with PCR and DNA sequencing. FX expression plasmids were constructed and transientby being transfected into 293T cells. FX: C and FX: Ag of the expression products were tested. Results APTT and PT in proband 1 were obviously prolonged, 113.4 s and 62.3 s, respectively. And there was no inhibitor in plasma. The thrombin generation was lower compared to normal reference. APTT and PT in proband 2 were 56. 5 s and 28.7 s. There was no inhibitor in the plasma. The thrombin generation was 1 101.5 nmol · min. APTT and PT in proband 3 were 117.3 s and 44. 3 s. The thrombin generation was 782.5 nmol · min. FX∶ C and FX∶ Ag in proband 1 were 1.4% and 3.6%, with a homozygous mutation in FX gene (Ser425→Pro). In vitro expression of the mutation showed a normal synthesis in the cell but secretion dysfuntion. In proband 2 F X: C and F X: Ag were 2. 2% and 5. 5%, with two heterozygous mutations in FX gene (Ala-29→Pro and Phe324→Leu). The Ala-29 → Pro mutation led to significantly reduced expressions of FX in both cell lysate and cell culture supernatants compared to wild-type plasmid,(41.32 ±5.21 )% and(6. 30 ± 1.84)% respectively. However Phe324→Leu mutation almost did not affect the FX synthesis. FX: C and FX: Ag in proband 3 were 2. 2% and 35%, with two heterozygous mutations in FX gene( Ala235→Thr and Arg347→Cys). The expressions of these two mutant FX proteins in cell lysate were similar to those of wild-type but obviously lower in the supernatant. Conclusions Five mutations of F X gene are found in this study. These mutations (Ser425Pro, Phe324Leu, Ala235Thr and Arg347Cys)can not affect F X protein synthesis. However Ala-29Pro mutation can reduce F X protein synthesis and cause secretion dysfunction.

Objective:To assess the safety and feasibility of single-port robotic radical cystectomy.Methods:During May 2019 and August 2019, nine patients (8 males, 1 female) received single-port robotic radical cystectomy by the same surgeon. The average age was 65.6(56-78)years. After a 4.5-5.5 cm trans-umbilical incision was made, Lagiport was inserted. Da Vinci Si system 1 #, 2 # arms and 30° lens were applied. Radical cystectomy and bilateral pelvic lymphadenectomy were performed without additional ports. Urinary diversion was completed outside the body. Uterus and vaginal anterior walls were also resected for female patient. Results:All 9 surgeries were successfully conducted without additional ports or conversion to laparoscopic and open surgery. The average operation time was 437.8(280-600)min. Urinary diversion methods included 2 orthotopic ileal neobladder, 5 ideal conduit and 2 cutaneous ureterostomy. Average estimated blood loss was 227.8(100-450)ml, without blood transfusion. Average intestinal recovery time was 3.1(2-4)days, drainage duration was 8.3(3-16) days, and postoperative hospital stays was 7.7(6-13) days. Pathological TNM stage: T 2aN 0M 0 6 cases, T 2bN 0M 0 1 case, T 3aN 3M 0 1 case, T isN 0M 0 1 case. All surgical margins were negative. One bowel obstruction was cured with fasting and indwelling gastric tube. During 9-12 months’ follow-up, no tumor recurrence and metastasis were observed. There was no hydronephrosis or ureterostenosis. All surgical incision healed well. Conclusions:For experienced surgeons, single-port robotic radical cystectomy is safe and feasible with small incision and fast recovery. Short-term clinical result is satisfied.

OBJECTIVE: To analyze the difference in gene expression profiles and screen silicosis development related differentially expressed genes(DEGs) and signaling pathways in peripheral blood specimens of rats exposed to silica dust using bioinformatics and gene chip. METHODS: GSE27023 gene expression profiles of peripheral blood samples of rats exposed to silica dust were downloaded from Gene Expression Omnibus database. After screening of the DEGs through paired-sample t-test and fold change method,DEGs related to rats exposed to silica dust was performed by Gene Ontology functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment analysis. The protein-protein interaction(PPI) network was constructed with the Search Tool for the Retrieval of Interacting Genes database and visualized using the software Cytoscape. RESULTS: Of the 2 767 DEGs screened,1 363 were up-regulated and1 404 were down-regulated. KEGG pathway enrichment analysis showed that 39 signaling pathways,such as the calcium signaling pathway,neuroactive ligand-receptor interaction,Ras-related protein 1 signaling pathway,were significantly enriched. DEGs enrichment and significance reached the highest level in the calcium signaling pathway. PPI network and module analysis suggested that mitogen-activated protein kinase 14(Mapk14),DNA-directed RNA PolymeraseⅡ,V-erb-a erythroblastic leukemia viral oncogene homolog 4,B-cell lymphoma-2(Bcl-2),receptor interacting serine/threonine kinase 4,PH domain leucine-rich repeat protein phosphatase 2,DNA-directed RNA polymerase Ⅲ,neurogenic locus notch homolog protein 1,histone deacetylase 1,yeast switch in mating type/Sucrose non fermentation related,matrix associated,actin dependent regulator of chromatin,subfamily a,member 4 were top 10 hub-proteins. Mapk14 had the highest node degree in up-regulated DEGs,and Bcl-2 had the highest node degree in down-regulated DEGs. CONCLUSION: We found 39 signaling pathways and 10 DEGs that are related to toxicity caused by exposure to silica dust in rats by analysis of peripheral blood gene chip data. Among them,calcium signaling pathway,Mapk14 and Bcl-2 may play important roles in the development and progress of silicosis in rats.

Alzheimer′s disease (AD) is an incurable disease in the field of major chronic diseases. Subjective cognitive decline (SCD) is a clinical risk factor for AD. The standardized screening and intervention in individuals with SCD are of great importance in early prevention and treatment of AD. According to the clinical criteria proposed by The characterisation of subjective cognitive decline, which was published online in Lancet Neurology, the article summarized the definition of SCD, the latest perspective of clinical standards in SCD, and the results of AD preclinical SCD research. The purpose of this work was to provide concrete guidance and recommendations for making clinical decisions in diagnosis and scientific research on SCD.

Objective: To explore the effects of ApoE epsilon4 (ApoE-ε4) alleles on cognitive function and resting-state functional MRI (rs-fMRI) in patients with amnestic mild cognitive impairment(aMCI) based on a prospective cohort study. Methods: An average of 20 months of prospective observations were conducted on 16 ApoE-ε4-carriers and 24 non-carriers of aMCI. Neuropsychological assessments and rs-fMRI data were collected at both baseline and follow-up. All participants were assessed by a battery of neuropsychological tests and underwent rs-fMRI. Two core regions of the default mode network (DMN), the left posterior cingulate cortex (PCC) and the medial prefrontal cortex (mPFC), were selected as seeds to calculate the functional connectivity. Two-way repeated measures analysis of variance was used to assess the effects of ApoE genotype(ε4-carriers, nonε4-carriers), interval and the interaction between these two factors for functional connectivity extracted from changed region found by t-test.Conversion rates of dementia were compared between ApoE-ε4-carriers and nonε4-carriers at follow-up using Chi-square test. For the comparison of functional connectivity and clinical data between ApoE-ε4-carriers and nonsε4-carriers in baseline and follow-up, the normal distribution test was carried out first. If the normal distribution was fitted, the two-sample t test was used, otherwise, the Mann-Whitney rank sum test was used. Finally, the general linear model was used to assess the relationships between alterations in functional connectivity and in neuropsychological assessments as well as the interaction effect. Results: (1)Significant decline in memory domains were found in ApoE-ε4-carriers as compared to non-carriers at both baseline and follow-up. The ApoE-ε4-carriers (14/16) presented a higher conversation rate than non-carriers(13/24, χ²=4.862, P=0.027) at follow-up. (2)Functional imaging analysis revealed that ApoE-ε4-carriers exhibited significantly higher functional connectivity between the left PCC and the left angular (ApoE-ε4-carriers: 0.23±0.11, non-carriers: -0.03±0.13, t=4.800, cluster size: 1 944 mm³, P=0.004), and between the left mPFC and the left angular (ApoE-ε4-carriers: 0.33±0.21, non-carriers: 0.08±0.18, t=5.040, cluster size:1 836 mm³, P=0.006) as compared to non-carriers at follow-up. We detected significant effect for the interaction interval by ApoE-ε4 on functional connectivity between the left angular and the left PCC (F=10.833, P=0.002)as well as the left mPFC (F=7.280, P=0.010). (3)The alteration of functional connectivity value between the left mPFC and the left angular in ApoE-ε4-carriers was positively correlated with the changes ofimmediate memory (r=0.692, P=0.018). The correlation was not statistically significant in ApoE-ε4-noncarriers (r=-0.198, P=0.417) and the integration effect was significant (F=8.632, P=0.006). Conclusions The ApoE-ε4 actually accelerates the deterioration of cognitive function in aMCI patients and carriers presented relatively reserved functional connectivity between the left angular and other core regions within DMN, which indicated the disruption of functional connectivity may be one of the underline mechanisms of ApoE-ε4 during AD process.