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Objective: To investigate the characteristics of hosts, antimicrobial susceptibility, and molecular epidemiology of mucoid serotype 3 Streptococcus pneumoniae (S. pneumoniae) isolated from children in China. Method: S. pneumoniae isolates collected between January 2016 and December 2019 were analyzed. S. pneumoniae isolates with mucoid phenotype were selected visually, and serotype 3 isolates were confirmed by Quellung reaction. The antimicrobial susceptibility was measured by E-test. Multilocus sequence typing was used for clonal analysis. Results: Twenty (3.04%) isolates of mucoid serotype 3 S. pneumoniae were identified from 657 clinical isolates, and all of them were noninvasive strains. The mean age of the hosts was 5.69 ± 3.28 years. The isolates included: 50.0% from the dissected tonsil or adenoid tissue in children with obstructive sleep apnea-hypopnea syndrome, 45.0% from sputum or bronchial lavages in children with pneumonia, and 5.0% from vaginal secretions of one patient with vulvovaginitis. All isolates were susceptible to penicillin, cefuroxime, ceftriaxone, meropenem, vancomycin, levofloxacin, trimethoprim/sulfamethoxazole, and rifampin but resistant to erythromycin. Sequence type (ST)505 and its clonal complex (CC) were the main genotypes (95%). Antimicrobial susceptibility of ST180 and ST505 were compared, and the minimum inhibitory concentration (MIC) of ST505 isolates was significantly higher than that of ST180 for tetracycline, trimethoprim/sulfamethoxazole, and meropenem. Conclusions: Mucoid serotype 3 Streptococcus pneumoniae can be isolated from various body parts, among which the respiratory system is the most common. It can cause noninvasive infection in children, and it has high susceptibility to a variety of antibiotics, especially β-lactams, but is resistant to macrolides. CC505 is the novel clonal complex found in China, which may be related to the worldwide mainstream clonal complex (CC180) but has its own biological characteristics. [ABSTRACT FROM AUTHOR]

[ Objective ]The present study was conducted to verify immunogenicity of Cryptosporidium andersoni oocyst wall protein (COWP) in order to lay the foundation for immunodiagnosis of cryptosporidiosis. [ Method ] According to the COWP sequence (DQ060431) was published in GenBank, a pair of primers was designed to amplify the COWP sequence by PCR method. The cloned COWP sequence was connected to pET-32a, and to construct pET-32a-COWP expression vector. Then recombinant strain was induced with IPTG, and its immunogenicity was determined by Western blotting. [Result]The cloned COWP sequence was 549 bp in length and had genomic homology of 99.9% with reference sequence (DQ060431). The recombinant strain was induced with 0.5 mmol/L IPTG for 5 h at 30 Ĕ, and expressed in the form of soluble protein mostly. The recombinant protein was purified by NTA-Ni affinity chromatog-raphy with 200 mmol/L imidazole eluent, and its molecular weight was 40 kDa. Anti-His rat monoclonal antibody or rat anti - Cryptosporidium andersoni serum treated as the first antibody detected by Western blotting could be found a clear target band respectively. [Conclusion]The recombinant protein COWP has high immunogenicity and can be used as a potential candidate antigen for immunodiagnosis of cryptosporidiosis. [ABSTRACT FROM AUTHOR]

Based on the conventional lumped parameter equivalent circuit model, the electrical characteristics of piezoelectric transformers (PTs) in series-parallel connection were analyzed using Y-parameter matrix. The voltage gain, output power and efficiency as function of parameters and the number of connected piezoelectric transformers were derived and simulated. And the electrical characteristics were simulated by using radial-mode vibrating PTs. Two piezoelectric transformers at the voltage gain of 0.081 6 with input and output parts isolated were tested. After series-parallel connection the voltage gain was reduced to 0.0406 on the same load of 20 ∩. The computed and experimental results verify the fact that the series-parallel connection of piezoelectric transformers can enhance the voltage step-down ratio. Series-parallel connected piezoelectric transformers can realize voltage step-down. [ABSTRACT FROM AUTHOR]

Objective  To evaluate the diagnostic yield of the multiplex polymerase chain reaction (PCR) method in cerebrospinal fluid (CSF) for the diagnosis of purulent meningitis (PM) in children. Methods  PM was diagnosed according to the European Society for Clinical Microbiology and Infectious Diseases guideline (2016). Patients with PM between May 2015 and October 2018 were included. The multiplex PCR method was used to detect eight common identified bacteria in PM. Its sensitivity and specificity were compared with bacteria culture. Results  A total of 106 cases were enrolled. Pathogenic bacteria were identified in 27 (25.5%) cases by culture and in 37 (34.9%) cases by multiplex PCR assay. The top three bacteria were Streptococcus pneumoniae , Escherichia coli K1, and Streptococcus agalactiae. When using culture as the gold standard, the multiplex PCR assay showed a sensitivity of 100, 88.9, and 75.0% for S. agalactiae , S. pneumoniae , and E. coli K1, respectively, and a specificity of more than 91.3% for all three bacteria. For detectable bacteria, the positive rate of the multiplex PCR assay (36.6%, 37/101) was significantly higher than that of the bacteria culture (21.8%, 22/101). When combining the two methods, etiology was identified in 42.5% (45/106) of the patients. Conclusion   Streptococcus pneumoniae , E. coli K1, and S. agalactiae were the predominant pathogens causing pediatric PM. As a rapid method with high sensitivity and specificity, the multiplex PCR assay in CSF could be used as an adjunctive approach with bacteria culture for the pathogen identification of PM. [ABSTRACT FROM AUTHOR]

In the title complex, [Co(C(15)H(12)N(3)O(4))(2)Cl(C(6)H(7)N)], the Co(III) ion is coordinated by two N atoms and two O atoms from two deprotonated Schiff base ligands, one N atom from a 4-methyl-pyridine ligand and one Cl atom, forming a distorted octa-hedral geometry. The Co(III) ion is displaced by 0.038 (2) Å from the equatorial plane towards the axial Cl atom.