A comparative study of genotyping and antimicrobial resistance between carbapenem-resistant Klebsiella pneumoniae and Acinetobacter baumannii isolates at a tertiary pediatric hospital in China.

Background: Carbapenem-resistant Klebsiella pneumoniae (CRKP) clinical isolations have rapidly increased in pediatric patients. To investigate a possible health care-associated infections of CRKP in a tertiary pediatric hospital, the circulating clones and carbapenem-resistant pattern between CRKP and carbapenem-resistant Acinetobacter baumannii (CRAB) isolates were compared to classify their epidemiological characteristics. The results will help to identify the epidemic pattern of the CRKP transmission in the hospital. Methods: Ninety-six CRKP and forty-eight CRAB isolates were collected in Kunming Children's Hospital from 2019 through 2022. These isolates were genotyped using repetitive extragenic palindromic-PCR (REP-PCR). Carbapenemase phenotypic and genetic characterization were investigated using a disk diffusion test and singleplex PCR, respectively. In addition, these characteristics of the two pathogens were compared. Results: The rates of CRKP and CRAB ranged from 15.8% to 37.0% at the hospital. Forty-nine and sixteen REP genotypes were identified among the 96 and 48 CRKP and CRAB isolates tested, respectively. The CRKP isolates showed more genetic diversity than the CRAB isolates. Of the 96 CRKP isolates, 69 (72%) produced Class B carbapenemases. However, all 48 CRAB isolates produced Class D carbapenemase or extended-spectrum ß-lactamases (ESBL) combined with the downregulation of membrane pore proteins. Furthermore, the carbapenemase genes bla KPC, bla IMP, and bla NDM were detected in CRKP isolates. However, CRAB isolates were all positive for the bla VIM, bla OXA-23, and bla OXA-51 genes. Conclusions: These CRKP isolates exhibited different biological and genetic characteristics with dynamic changes, suggesting widespread communities. Continuous epidemiological surveillance and multicenter research should be carried out to strengthen the prevention and control of infections.

Viral etiology of acute respiratory tract infection among children under 5 years of age in Kunming City, China: a matched case-case-control study.

AIMS: Nucleic acid-based molecular techniques in current laboratory practice allow the identification of a broad range of respiratory viruses. However, due to asymptomatic carriage, the detection of viruses in the respiratory tract does not necessarily indicate disease. The study aimed to investigate infections of different viruses that colonize the airways, the viral combinations in coinfection, and the viral association with the occurrence of either upper respiratory tract infection (AURTI) or lower respiratory tract infection (ALRTI) in children. METHODS AND RESULTS: A matched case-case-control study included ALRTI cases, AURTI cases, and healthy controls was conducted at Kunming Children's Hospital. Oropharyngeal swabs from the three groups were collected for eight viral pathogens detection by multiplex RT-PCR. The association of each pathogen with disease status was determined by comparing the results between cases and controls. From 1 March 2021 through 28 February 2022, 278 participants in each group were investigated. Viral infection was detected in 54.0%, 37.1%, and 12.2% of the ALRTI cases, AURTI cases, and healthy controls, respectively. Human respiratory syncytial virus (RSV), adenovirus (ADV), and parainfluenza virus-3 (PIV-3) were the most frequently documented viruses. RSV/ADV was the most frequent combination detected in coinfection. When compared to healthy controls, RSV and PIV-3 were independently associated with both ALRTI and AURTI. CONCLUSIONS: RSV and PIV-3 were causes of both ALRTI and AURTI cases. These results provide initial evidence of the potential of microbiota-based diagnostics for the differential diagnosis of severe acute respiratory infections using oropharyngeal swab samples.

[Bone marrow derived endothelial cells promote healing of acute intimal injury in carotid arteries of rabbits].

OBJECTIVE: To investigate the effect of bone marrow derived endothelial cells implantation on healing of acute injured intima. METHODS: Mononuclear cells derived from bone marrow were differentiated to endothelial cells. The cells were labeled with bromodeoxyuridine. Carotids injuring was induced by a balloon in 40 rabbits, endothelial cell suspension (2 x 10(6)/ml, n = 20) or PBS (2 ml, n = 20) was infused to injured arteries. The intima covered area was tested by Evan's Blue staining. The average intima thickness and media thickness were observed 7 and 14 days post procedure by histological assay. The immunofluorescent staining was performed for testing the BrdU labeled-cells, and these cells were detected under a fluorescent microscope. RESULTS: Intima covered area rate was significant higher (54.1% +/- 8.2% vs. 30.0% +/- 5.5% at day 7, and 81.8% +/- 6.0% vs. 63.6% +/- 8.4% at day 14, all P < 0.05) and the intima thickness and media thickness were significantly reduced in the endothelial cell suspension group. CONCLUSION: The bone marrow derived endothelial cell promoted healing post intima injury in this model compared to PBS group (all P < 0.05).

Effects of metoprolol on sympathetic remodeling and electrical remodeling at infarcted border zone after myocardial infarction in rabbits.

BACKGROUND: The findings of sympathetic remodeling and its electrophysiological implications force us to rerecognize the drugs presently used. The aim of this study was to investigate the effects of metoprolol on sympathetic remodeling and electrical remodeling at the infarcted border zone (IBZ) after myocardial infarction (MI). METHODS: Forty rabbits were randomly assigned into two groups: MI group (n = 20), ligation of the anterior descending coronary; Metoprolol group (n = 20), ligation of the anterior descending coronary and administration of oral metoprolol 5 mg/kg/day. Eight weeks after surgery, transmural dispersion of repolarization (TDR) at baseline, TDR and difference of TDR (deltaTDR) during sympathetic nerve stimulation were measured at the IBZ. The distribution and densities of growth associated protein 43 and tyrosine hydroxylase positive nerves at the IBZ were detected with immunohistochemical techniques. RESULTS: The study was completed in the 36 surviving animals (18 rabbits in each group). The densities of growth associated protein 43 and tyrosine hydroxylase positive nerves in the Metoprolol group (2,550 +/- 554 and 1,779 +/- 458 microm2/mm2, respectively) were lower than in the MI group (3,217 +/- 589 and 2,616 +/- 528 microm2/mm2, respectively; both p < 0.01). TDR at baseline, TDR and deltaTDR during sympathetic nerve stimulation were shorter in the Metoprolol group than in the MI group (p < 0.01 for all). CONCLUSION: Metoprolol can inhibit sympathetic remodeling and electrical remodeling at the IBZ after MI. The association of metoprolol with improved electrical remodeling may be partly related to the inhibition of sympathetic remodeling.

Quality of life and cost for patients with premature ventricular contractions by radiofrequency catheter ablation.

OBJECTIVE: To evaluate the quality of life (QoL), health-care resource utilization, and cost for the patients with premature ventricular contractions (PVCs) by radiofrequency catheter ablation (RFCA). METHODS: RFCA was performed in 58 patients with symptomatic PVCs that were refractory/easy to medication. A 24-hour ambulatory electrocardiographic monitoring, QoL, health-care resources utilization, and cost were assessed at a screening visit and 3 and 12 months after RFCA. RESULTS: RFCA was successfully performed in 56 patients (96.6%). This resulted in a significant improvement in the QoL at 3 and 12 months after the procedure. There were no major complications related to the procedure. Nine patients (15.5%) had residual arrhythmia. Seven of them underwent repeated ablation with successful results. It also improved the QoL and reduced health-care resource utilization and cost. CONCLUSIONS: RFCA is a safe and effective treatment for PVCs, and it is a viable alternative to drugs in the presence of disabling symptoms.