[Molecular epidemiology of drug resistance genes and carbapenem resistance of Pseudomonas aeruginosa in rural well water].

Objective: To analyze molecular epidemiological characteristics of drug resistance genes and carbapenem resistance of Pseudomonas aeruginosa (PA) in rural well water. Methods: According to Citation of Natural Mineral Water Inspection (GB 8538-2016), a total of 112 well water samples were tested in Juye county of Shandong province, and PFGE and drug susceptibility test were conducted for the identified PA strains. After PCR identification of carbapenem resistance genes, S1-PFGE and Southern blotting were used to determine the location of drug resistance genes, and combined experiments were used to determine gene transferability. Results: The detection rate of PA in rural well water samples in Juye county of Shandong province was 54.46% (61/112). The 61 strains could be divided into 56 PFGE types. There were 2 strains with 100.00% consistent band types, and there was no obvious predominant band type. The results of drug susceptibility experiments showed that 93.44% (57/61) were multi-drug resistant strains, and there were 2 strains carrying blaVIM-2, both of which were located on the plasmid, and both of them were transferred horizontally with the plasmid. Conclusion: PA carrying carbapenem resistance genes was detected in well water of rural communities in Juye country, and there is the possibility of horizontal transmission of such resistance genes.

[Challenges to prevent and control the outbreak of COVID-19].

An outbreak of severe pneumonia of unknown cause was reported in December 2019 in Wuhan, Hubei province, China. The infectious virus was soon identified and named as 2019 novel coronavirus (2019-nCoV). The name of the COVID-19 was given by WHO on 11 February 2020. It has so far caused about 118 000 cases in 114 countries including China ending March 10, and was characterized as a pandemic by WHO on March 11. We still face great challenges in control of the epidemic: uncertain initial source of infection, infected populations widely scattered, complex routs of transmission, populations generally susceptible, high contagiousness of the virus, and finally vaccines unlikely available in the near future.

[Multi locus sequence typing and antibiotic susceptibility of extended-spectrum beta-lactamases producing Enterobacteriaceae in rural residents in villages with pig-breeding farms in Shandong province].

Objective: To analyze the antimicrobial resistance and multilocus sequence typing (MLST) results of extended-spectrum ß-lactamase (ESBLs)-producing Escherichia coli in rural residents in villages with pig breeding farms in a county of Shandong province. Methods: Antimicrobial susceptibility testing was performed with agar dilution method by using 360 ESBLs-producing E. coli strains from fresh stool samples of rural residents in villages with pig breeding farms in a county of Shandong. PCR was conducted to amplify the CTX-M, TEM, SHV genes and capillary electrophoresis was used to screen positive strains in July, 2016. MLST was performed for molecular typing analysis, and eBURST v3.0 software was used for cluster analysis. Results: Among 360 strains of ESBLs-producing E. coli, the resistance rates to cefotaxime, tetracycline, trimethoprim-sulfamethoxazole and florfenicol were 100.0% (360/360), 82.2% (296/360), 81.1% (292/360) and 80.3% (289/360), respectively. The positive rate of CTX-M gene was 99.2% (357/360), in which the positive rate of CTX-M-9 was 35.6% (128/360) and the positive rate of CTX-M-1 was 24.4% (88/360). The positive rate of TEM gene was 26.9% (97/360). A total of 132 STs were identified through MLST. The predominant ST was ST10, accounting for 12.5% (45/360). Cluster analysis showed that CC10 was the most important clone group, including 39 ST clones, involving 148 strains (41.1%). Conclusions: The drug resistances of ESBLs-producing E. coli to cefotaxime, tetracycline, trimethoprim-sulfamethoxazole and flurfenicol are serious in this rural area. There is a small-scale clustering of CC10 and transmission mode from animals to humans might exist.

[Serotype identification and antibiotic susceptibility of Shiga toxin-producing Escherichia coli in the Weishan area in Shandong Province, China].

Objective: To determine the serotypes and drug resistance profiles of Shiga toxin-producing Escherichia coli (STEC) in animal stools from the Weishan area in Shandong Province, China. To provide the basis for further study. Methods: Five hundred animal stool samples (from pigs, cattle, sheep, dogs and birds) were collected from the Weishan area and STEC strains were isolated from these samples. Strains were serotyped by a serum agglutination test, and their drug resistance profiles were determined through antimicrobial sensitivity experiments. In this study, PCR was used to detect tetracycline resistance genes (tetA, tetB, tetC, tetD) and beta-lactam resistance genes (blaSHV-1, blaCTX-M, blaTEM). Results: Sixteen strains of STEC were isolated from animal stool samples. Thirteen strains were isolated from pig stool samples, two from bovine stool samples and one from a sheep stool sample. Two of the strains were identified as E. coli O157:H7, and other 14 strains were non-O157 STEC of different serotypes. Antimicrobial sensitivity experiments showed that 15 of the strains were multidrug resistant. The rates of resistance were as follows: nalidixic acid (12/16 strains), sulfisoxazole (11/16), trimethoprim and sulphame-thoxazole (11/16), doxycycline (9/16), azithromycin (9/16), tetracycline (9/16), chloramphenicol (8/16) and streptomycin (8/16). Therefore, nalidixic acid showed the highest rate of resistance among the strains, followed by trimethoprim and sulphame-thoxazole, and sulfisoxazole. Resistance to cefepime or imipenem was not detected. In total, three types of drug resistance genes (tetA, tetB and tetC) were detected among the 16 strains. Conclusion: The results showed that STEC strains isolated from animals in the Weishan area were of a range of serotypes. The 16 strains of STEC isolated from animal stools in this area were resistant to a number of antibiotics, with many strains displaying multidrug resistance.

[Meta-analysis on epidemiology of iatrogenic-borne methicillin-resistant Staphylococcus aureus].

OBJECTIVE: To study the molecular-biologic characteristics and epidemiological status of iatrogenic related Community-acquired methicillin-resistant Staphylococcus (S.) aureus (CA-MRSA) in China through Meta-analysis. METHODS: Data through systematic searching for peer-reviewed articles published before December 3(rd), 2015 from 4 main electronic databases including China National Knowledge Infrastructure (CNKI), Wanfang Data, PubMed and Web of Science Core Collection was collected, for this Meta-analysis. PRISMA guidelines were followed and the proportion of MRSA, CA-MRSA, hospital-acquired MRSA (HA-MRSA) and panton-valentine leucocidin (PVL) gene in certain populations were quantitatively analyzed by Stata 13.0 software. RESULTS: Average proportion of CA-MRSA from S. aureus was 12% (95%CI: 8%-16%). CA-MRSA in MRSA was 18% (95%CI: 12%-24%). 42.1% (95%CI: 20.4%-63.7%) of the CA-MRSA carried a PVL gene, and the number was higher than general MRSA (t=-2.99,P=0.011). CONCLUSION: CA-MRSA was in lower proportion than HA-MRSA, both seen in general MRSA and in S. aureus, but under higher proportion of carrying the PVL gene. Transmission of CA-MRSA could be prevented within the general population through conducting effective surveillances and preventive programs.

A cluster of person-to-person transmission cases caused by SFTS virus in Penglai, China.

An emerging infectious disease, severe fever with thrombocytopenia syndrome (SFTS), was identified to be associated with a novel SFTS virus (SFTSV). Transmission of the disease among humans has been described, but clinical impact factors and transmission mechanisms still need further study. An outbreak of person-to-person transmission of SFTS in a cluster of nine patients that occurred in an SFTS endemic area, Penglai County, Shandong province, China, was investigated. We found that the onset date of all eight secondary SFTS patients ranged from 7 to 13 days after exposure to the corpse of the index patient, and clinical incubation time was mostly focused on 9-10 days (n = 6). The two dead patients, including the index patient and one secondary infected patient, presented unusually high levels of viral load (6 × 10(8-9) copies/mL), low levels of platelets count (<55 × 10(9)/L), and significant increase of alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, and creatine kinase values in the second week, and died on day 10 or 11 after disease onset. Genetic sequencing revealed 100% homology among virus strains isolated from the index patient and five secondary patients. Risk factors assessment of the person-to-person transmission revealed that the major exposure factor was blood contact without personal protection equipment. Information from this study provided solid references of SFTS incubation time, clinical and laboratory parameters related to SFTS severity and outcome, and biosafety issues for preventing person-to-person transmission or nosocomial infection of SFTSV.

[The effect of low doses of recombinant human erythropoietin on renal anemia in predialysis patients with chronic renal failure].

Subcutaneous (s.c.) administration of recombinant human erythropoietin (rHuEPO) has been proven to be effective in anemia of predialysis patients with chronic renal failure (CRF). However, the optimal dosage and frequency of administration have not been established. We use low dose (< 100U.kg-1.w-1) of s.c. rHuEPO to treat renal anemia in two groups (group A: n = 18, twice a week; group B; n = 14, once a week) of nondialytic CRF patients. Hb and Hct gradually increased 1-3 months aftes rHuEPO treatment in the two groups. The incidence of hypertension, one of the main side effects, was lower (4/18 in Group A, 4/14 in Group B) than that reported in the literature. These results showed that either twice weekly or once weekly s.c. injection of low dose rHuEPO is effective and there will be less side effects treating predialysis patients with CRF.

[Effects of alpha-ketoacids therapy on protein metabolism and secondary hyperparathyroidism in predialysis patients].

The effects of alpha-ketoacids (alpha-KA) on azotemia, plasma amino acids concentrations, nitrogen balance, serum Ca, PO4 and iPTH levels in 22 predialysis patients were investigated. The results showed that BUN and serum phosphate levels decreased significantly, plasma essential amino acids levels, nitrogen balance and serum calcium levels were improved after 6-8 weeks of alpha-KA therapy. The serum iPTH levels were reduced markedly three months after alpha-KA treatment and maintained lower ten months later.

[Treatment of chronic renal failure with Oenothera beinnis L in rats with subtotal nephrectomy].

The effect of orally administered Oenothera Biennis L on chronic renal failure was studied in the partially nephrectomized rats. As compared with the control groups, the group treated with Oenothera showed the following features. 1) Urine protein excretion was reduced; 2) Level of serum cholesterol decreased; 3) Scr maintained the same level as before treatment; 4) Level of PGE1 and PGE2 increased both in renal cortex and medulla; 5) 6-keto PGF1 alpha increased in cortex; 6) Increased TXB2 production was only observed 4 weeks after nephrectomy; 7) Glomerular lesions were more severe in control group. It is concluded that Oenothera Biennis L has beneficial effect on the remnant kidney and may be useful as a kind of conservative treatment for chronic renal failure.

[Effect of low protein diet, plus essential amino acids on lipid metabolism in patients with chronic renal failure].

We investigated lipoprotein profile of 18 non-dialysis patients with CRF and 17 patients on hemodialysis, and studied effect of LPD plus EAA on lipid metabolism of 18 non-dialysis patients with CRF. The results revealed that total triglyceride, cholesterol, LDL, VLDL, and semi-quantity of ApoCII, ApoCIII were significantly increased, and HDL, ApoAI ApoAI/ApoB rate, semiquantify of ApoCI were significantly reduced in non-dialysis patients and patients on hemodialysis; VLDL and Ccr were closely negative related in non-dialysis patients. The lipid abnormalities were more severe in non-dialysis patients complicated with hypertension than without hypertension. After 6 to 10 weeks' LPD plus EAA treatment in 18 non-dialysis patients, total triglyceride, cholesterol, LDL, VLDL were significantly reduced, and HDL, ApoAI, ApoAI/ApoB were significantly increased. We conclude that it is characterized by type IV hyperlipidemia in lipid abnormalities of patients with CRF, and LPD plus EAA treatment may improve it effectively.

[Legionnaires disease associated with acute renal failure].

It has been suggested that tubular-interstitial damage may be the main cause of Legionnaires disease (LD) associated acute renal failure (ARF). However, this hypothesis has rarely been examined. In China we firstly describe four patients with LD-ARF, who had proteinuria, hematuria, Leukocyturia and cylindruria. Two patients had nephrotic syndrome indicating acute glomerular injure, one of them was histopathologically proven to be rapidly progressive glomerulonephritis. Scr, UNa, RFI and FENa are markedly increased. Our results suggest that both tubular-interstitial and glomerular damage may be the important causes of LD-ARF in Chinese LD patients. To confirm this hypothesis further investigation are needed.

[Primary nephrotic syndrome associated with renal tubular dysfunctions: renal morphologic alteration and response to treatment].

To evaluate the importance of renal tubular dysfunctions (RTD) in the patients with primary nephrotic syndrome (NS), renal tubular functions tests and renal biopsies were taken in 25 cases with NS. They were divided into two groups: A. with RTD (15 cases); B. without RTD (10 cases). Four glomerular pathological types were found in 22 cases: 15 cases with MePGN, 2 cases with IgAN, 4 cases with MPGN, 1 case with SGN. Degrees of pathological alteration of renal tubules were as follows: 5 cases in grade 0, all from group B. 11 cases in grade I, 7 belong to group A and 4 to group B. Each 3 cases in Grade II and grade III, all of them from group A. Treatment with steroids and cyclophosphane resulted in complete remission in 1 case and no effect in 11 cases of group A, and complete remission in 6 cases and no effect in 3 cases of group B. NS associated with RTD is common in adults, and its major clinical characteristic is resistant to steroid therapy. RTD is closely related to renal tubular morphological changes, and is not related to pathological classification of glomerular alteration.