Associations between digital literacy, health literacy, and digital health behaviors among rural residents: evidence from Zhejiang, China.

OBJECTIVE: Within the digital society, the limited proficiency in digital health behaviors among rural residents has emerged as a significant factor intensifying health disparities between urban and rural areas. Addressing this issue, enhancing the digital literacy and health literacy of rural residents stands out as a crucial strategy. This study aims to investigate the relationship between digital literacy, health literacy, and the digital health behaviors of rural residents. METHODS: Initially, we developed measurement instruments aimed at assessing the levels of digital literacy and health literacy among rural residents. Subsequently, leveraging micro survey data, we conducted assessments on the digital literacy and health literacy of 968 residents in five administrative villages in Zhejiang Province, China. Building upon this foundation, we employed Probit and Poisson models to empirically scrutinize the influence of digital literacy, health literacy, and their interaction on the manifestation of digital health behaviors within the rural population. This analysis was conducted from a dual perspective, evaluating the participation of digital health behaviors among rural residents and the diversity to which they participate in such behaviors. RESULTS: Digital literacy exhibited a notably positive influence on both the participation and diversity of digital health behaviors among rural residents. While health literacy did not emerge as a predictor for the occurrence of digital health behavior, it exerted a substantial positive impact on the diversity of digital health behaviors in the rural population. There were significant interaction effects between digital literacy and health literacy concerning the participation and diversity of digital health behaviors among rural residents. These findings remained robust even after implementing the instrumental variable method to address endogeneity issues. Furthermore, the outcomes of robust analysis and heterogeneity analysis further fortify the steadfastness of the aforementioned conclusions. CONCLUSION: The findings suggest that policymakers should implement targeted measures aimed at enhancing digital literacy and health literacy among rural residents. This approach is crucial for improving rural residents' access to digital health services, thereby mitigating urban-rural health inequality.

Research on the sensitivity of Streptococcus agalactiae to omadacycline / 中国热带医学

@#Abstract: Objective　To investigate the antimicrobial activity of omadacycline (OMC) against clinical Streptococcus agalactiae (GBS) isolates, as well as its relationship with biofilm formation, resistance genes and virulence genes. Methods　A total of 136 strains of Streptococcus agalactiae isolated from Shenzhen Nanshan People's Hospital between 2015 to 2020. The minimum inhibitory concentration (MIC) of OMC against Streptococcus agalactiae was determined by broth microdilution. Crystal violet staining was used to detect the biofilm formation ability of GBS. Resistance genes (tetM, tetO, tetK, ermB, OptrA) and virulence genes (cpsⅢ, bca, fbsA, cpsA, scpB) were investigated by polymerase chain reaction (PCR). Results　Among the 136 clinical isolates of GBS, 20 strains (14.7%) were resistant to OMC, 64 (47.1%) were intermediate, and 52 (38.2%) were sensitive. Fifty-seven strains (41.9%) were biofilm-positive, 20 of which (35.1%) were sensitive to OMC. Seventy-nine strains (58.1%) were biofilm-negative, 32 of which (40.5%) were susceptible to OMC. There was a statistically significant difference in the sensitivity rates between the two groups of strains (χ2=63.062, P<0.001), but there was no significant difference in the sensitivity of OMC among the biofilm-positive strains (Fisher's exact test, P=0.824). The resistance rates of tetM, tetO, ermB and OptrA positive strains were higher than those of negative strains, while tetK was opposite. The presence of tetM (Z=0.815, P=0.415), tetO (Z=0.151, P=0.88), tetK (Z=0.567, P=0.571), ermB (Z=1.198, P=0.231) resistance genes in Streptococcus agalactiae had no significant impact on the sensitivity of OMC. However, the presence of the OptrA resistance gene showed a statistically significant effect on the sensitivity of OMC (Z=2.913, P=0.004). The virulence factors cpsⅢ, bca, fbsA, cpsA and scpB were all detected at a rate higher than 50%. The presence of the virulence genes cpsⅢ (Z=0.222, P=0.824), bca (Z=0.141, P=0.888), fbsA (Z=0.813, P=0.416), and cpsA (Z=1.615, P=0.106) in Streptococcus agalactiae had no significant impact on the sensitivity of OMC. However, there was a significant inter-group difference in the scpB virulence gene (Z=2.844, P=0.004), but the rank mean values and resistance rates of scpB-positive strains were lower than those of the negative strains. Conclusions　The formation of biofilm in Streptococcus agalactiae reduces its sensitivity to OMC, but there was no significant difference in the sensitivity to OMC among the biofilm-positive strains. The presence of resistance genes tetM, tetO, tetK, ermB, and virulence genes cpsⅢ, bca, fbsA, cpsA, scpB in Streptococcus agalactiae is not associated with OMC resistance, but the presence of the resistance gene OptrA is correlated with OMC resistance..

Linezolid Consumption Facilitates the Development of Linezolid Resistance in Enterococcus faecalis in a Tertiary-Care Hospital: A 5-Year Surveillance Study.

Although case reports and clinical studies of linezolid (LZD)-resistant Enterococcus faecalis (LREF) have gradually increased in recent years, the relationship between LZD resistance and antibiotic consumption in hospital settings still remains unclear. In this study, we aimed to investigate the dynamic relationship between the yearly detection frequency of LREF clinical isolates and yearly consumption of LZD and vancomycin (VCM) over a 5-year period in a Chinese hospital setting. Antibiotic consumption data (LZD and VCM) from 2011 to 2015 were obtained from a computerized database and recalculated as the defined daily doses (DDDs) per 100 bed-days (DBD). All 268 E. faecalis clinical isolates were retrospectively collected from 2011 to 2015 in this hospital. LZD resistance mechanism and multilocus sequence typing of E. faecalis were determined by PCR. The annual detection frequency of LREF clinical isolates tested in this hospital was shown with 1.89% (1/53), 2% (1/50), 2.04% (1/49), 0% (0/45), and 7.04% (5/71), respectively, and the detection frequency of LZD-nonsusceptible E. faecalis (LNSEF; n = 59, including LZD-resistant and intermediate isolates) was determined with 26.42% (14/53), 34% (17/50), 16.33% (8/49), 22.22% (10/45), and 14.08% (10/71), respectively. Spearman correlation analysis revealed that LZD DBD significantly correlated positively with the detection frequency of LREF (r = 0.886, p = 0.019). Moreover, VCM DBD significantly correlated positively with the frequency of LNSEF (r = 0.943, p = 0.005). Furthermore, the detection frequency of optrA-positive E. faecalis also correlated positively with high LZD consumption load in this hospital setting. Conclusively, high LZD consumption load facilitates the development of LZD resistance and promotes the selection of optrA-positive E. faecalis clinical isolates under antibiotic pressure in a hospital setting.

Biofilm formation in erythromycin-resistant Staphylococcus aureus and the relationship with antimicrobial susceptibility and molecular characteristics.

PURPOSE: In this study, we aimed to investigate biofilm formation characteristics in clinical Staphylococcus aureus (S. aureus) isolates with erythromycin (ERY) resistance from China and further analyze their correlations with antimicrobial susceptibility and molecular characteristics. METHODOLOGY: A total of 276 clinical isolates of ERY-resistant S. aureus, including 142 methicillin-resistant S. aureus (MRSA) strains and 134 methicillin-susceptible S. aureus (MSSA) strains, were retrospectively collected in China. Biofilms were determined by crystal violet staining and ERY resistance genes (ermA, ermB and ermC) were detected by polymerase chain reaction. Inducible clindamycin resistance was examined by D test and multilocus sequence typing, and clonal complexes (CCs) based on housekeeping genes were further determined. RESULTS: The frequency of biofilm formation among ERY-resistant S. aureus was 40.9% (113/276) in total and no significant difference was found for the frequency of biofilm formation between ERY-resistant MRSA and ERY-resistant MSSA (44.4% vs 37.3%, P > 0.05). In ERY-resistant MRSA isolates, the frequency of biofilm formation in ermA-positive, gentamicin-resistant and ciprofloxacin-resistant isolates was higher than that in ermA-negative, gentamicin-sensitive and ciprofloxacin-sensitive isolates, respectively (63.9% vs 23.6%, P < 0.01; 60.3% vs 27.5%, P < 0.01; 65.2% vs 26.3%, P < 0.01). In addition, tetracycline resistance facilitated biofilm formation in both ERY-resistant MRSA and MSSA and the frequency of biofilm formation in CC239- or CC7S. aureus isolates with ERY resistance was significantly higher compared with that in CC59S. aureus (both P < 0.01). CONCLUSION: The ermA gene, and gentamicin, ciprofloxacin and tetracycline resistance facilitate biofilm formation in ERY-resistant MRSA isolates and, moreover, ERY-resistant S. aureus isolates with positive biofilm formation exhibited clonality clustering regarding CC239 and CC7.

Comparative genome and evolution analysis of the locus of enterocyte effacement from enteropathogenic Escherichia coli Deng and its transcriptional response to ciprofloxacin.

PURPOSE: In this study, we aimed to investigate the genomic characteristics and evolution of pathogenicity islands of an enteropathogenic Escherichia coli (EPEC) strain, and to obtain a transcriptional profile of EPEC under different concentrations of ciprofloxacin using microarray analysis. METHODOLOGY: The complete EPEC Deng genome was sequenced and compared to genomes of 12 previously sequenced E. coli strains. A 180 min time course experiment was performed in which the effect of ciprofloxacin on EPEC Deng growth was evaluated. Microarray profiling was used to study the effect of varying ciprofloxacin pressure on genome-wide transcriptional expression. Differential expression of the genes identified using microarray data was confirmed using real-time quantitative reverse transcriptase PCR (RTQ). Target gene-defective recombineering strains were created to investigate the influence of the grlA gene on ciprofloxacin susceptibility. RESULTS: Genomic comparisons revealed a close phylogenic relationship between EPEC Deng and E. coli strains O111_H_11128 and O26_H11_11368, with low genetic diversity among their type III secretion system genes and typically genetic variation in the map, tir, eae and espA genes of EPEC. It is noteworthy that 21 genes were down-regulated at all time points examined in the group exposed to 2 µg ml-1 of ciprofloxacin. A grlA-mutant derivative with increased susceptibility to ciprofloxacin was discovered. CONCLUSIONS: The present findings provide an overview of the phylogenetic characteristics of EPEC Deng and its transcriptional response to ciprofloxacin, further suggesting that GrlA may play a clinically important role in EPEC responses to ciprofloxacin.

Effect of tedizolid on clinical Enterococcus isolates: in vitro activity, distribution of virulence factor, resistance genes and multilocus sequence typing.

Enterococcal infections have become one of the most challenging nosocomial problems. Tedizolid, the second oxazolidinone, is 4-fold to 8-fold more potent in vivo and in vitro than linezolid against enterococci. However, the characteristics of tedizolid related to enterococci isolates in China remain elusive. The aim of this study was to evaluate in vitro activity of tedizolid against enterococcal isolates from patients with infections at a teaching hospital in China and to investigate the correlations between in vitro tedizolid activity against enterococci and the distribution of multilocus sequence types (MLST), resistance genes and virulence factors. A total of 289 non-duplicate Enterococcus faecalis strains and 68 E. faecium strains were isolated. Tedizolid inhibited 95.24% of all enterococcal isolates with an MIC ≤ 0.5µg/ml. Seventeen E. faecalis strains had an MIC > 0.5 µg/ml, and all E. faecium were inhibited at MIC ≤ 0.5 µg/ml. The proportion of tedizolid non-susceptible E. faecalis strains with optrA genes was higher than that among tedizolid-susceptible strains. Tedizolid exhibited good in vitro activity against all E. faecium strains, including multidrug-resistant E. faecium carrying tet(M), tet(L), tet(U),erm(A), erm(B) and erm(C) genes. In summary, tedizolid has an advantage (higher sensitivity rate) compared to linezolid among enterococci, except for isolates expressing the plasmid-encoded optrA gene.

Inhibition of Adhesion of Enteropathogenic Escherichia coli to HEp-2 Cells by Binding of a Novel Peptide to EspB Protein.

Enteropathogenic Escherichia coli (EPEC) is a major cause of infantile diarrhea in developing countries. The translocator EspB is a key virulence factor in the process of the attaching and effacing effect of EPEC and plays a critical role in the pathogenesis of the bacteria. In this study, we aimed to select the peptides binding to EspB protein by phage display library and further investigate whether these peptides can decrease the extent of invasion and virulence of EPEC on host cells by targeting to EspB protein. The expression and purification of EspB protein from E. coli was demonstrated by Western blotting. The Ph.D. 12-mer peptide phage display library was used to screen the candidate peptides binding specifically to EspB protein. Furthermore, the affinity of these candidate peptides bound to EspB was identified by enzyme-linked immunosorbent assay (ELISA). Moreover, we investigated whether these screened peptides could decrease the adherence ratio of EPEC to HEp-2 cells with increasing concentration. Successful purification of EspB protein from pET21b-EspB-transformed E. coli was identified by Western blotting. Then, the candidate peptides including phages 6, 7, 8, and 12 were screened by the Ph.D. 12-mer peptide phage display library and ELISA test demonstrated that their affinity binding to EspB protein was high compared with the control. Functional analysis indicated that synthetic peptide-6 (YFPYSHTSPRQP) significantly decreased the adherence ratio of EPEC to HEp-2 cells with increasing concentration (P < 0.01). Peptide-6 (100 µg/mL) could lead to a 40 % decrease in the adherence ratio of EPEC to HEp-2 cells compared with control (P < 0.01). However, the other three peptides at different concentrations showed only a slight ability to block the adherence of EPEC to host cells. Our data provided a potential strategy to inhibit the adhesion of EPEC to epithelial cells by a candidate peptide targeted toward EspB protein.

Identification of Infantile Diarrhea Caused by Breast Milk-Transmitted Staphylococcus aureus Infection.

Staphylococcus aureus is a well-known organism which is responsible for a variety of human infectious diseases including skin infections, pneumonia, bacteremia, and endocarditis. Few of the microorganisms can be transmitted from mother to the newborn or infant by milk breastfeeding. This study aims to identify transmission of S. aureus from healthy, lactating mothers to their infants by breastfeeding. Stool specimens of diarrheal infants and breast milk of their mother (totally three pairs) were collected and six Staphylococcus aureus isolates were cultured positively. Homology and molecular characters of isolated strains were tested using pulsed-field gel electrophoresis (PFGE), spa typing, and multilocus sequence typing. Furthermore, toxin genes detection was also performed. Each pair of isolates has the same PFGE type and spa type. Four Sequence types (STs) were found among all the isolates; they are ST15, ST188, and ST59, respectively. Among the strains, seb, sec, and tst genes were found, and all were negative for pvl gene. The homology of the S. aureus strains isolated from the infants' stool and the mothers' milk was genetically demonstrated, which indicated that breastfeeding may be important in the transmission of S. aureus infection, and the character of S. aureus needed to be further evaluated.

Directed shift of vaginal microbiota induced by vaginal application of sucrose gel in rhesus macaques.

OBJECTIVES: Sucrose gel was used to treat bacterial vaginosis in a phase III clinical trial. However, the changes of vaginal flora after treatment were only examined by Nugent score in that clinical trial, While the vaginal microbiota of rhesus macaques is characterized by anaerobic, Gram-negative bacteria, few lactobacilli, and pH levels above 4.6, similar to the microbiota of patients with bacterial vaginosis. This study is aimed to investigate the change of the vaginal microbiota of rehsus macaques after topical use of sucrose gel to reveal more precisely the bacterial population shift after the topical application of sucrose gel. METHODS: Sixteen rhesus macaques were treated with 0.5 g sucrose gel vaginally and three with 0.5 g of placebo gel. Vaginal swabs were collected daily following treatment. Vaginal pH levels and Nugent scores were recorded. The composition of the vaginal micotbiota was tested by V3∼V4 16S rDNA metagenomic sequencing. Dynamic changes in the Lactobacillus genus were analyzed by qPCR. RESULTS: The vaginal microbiota of rhesus macaques are dominated by anaerobic Gram-negative bacteria, with few lactobacilli and high pH levels above 4.6. After five days' treatment with topical sucrose gel, the component percentage of Lactobacillus in vaginal microbiota increased from 1.31% to 81.59%, while the component percentage of Porphyromonas decreased from 18.60% to 0.43%, Sneathia decreased from 15.09% to 0.89%, Mobiluncus decreased from 8.23% to 0.12%, etc.. The average vaginal pH values of 16 rhesus macaques of the sucrose gel group decreased from 5.4 to 3.89. There were no significant changes in microbiota and vaginal pH observed in the placebo group. CONCLUSIONS: Rhesus macaques can be used as animal models of bacterial vaginosis to develop drugs and test treatment efficacy. Furthermore, the topical application of sucrose gel induced the shifting of vaginal flora of rhesus macaques from a BV kind of flora to a lactobacilli-dominating flora.

Recurrent linezolid-resistant Enterococcus faecalis infection in a patient with pneumonia.

OBJECTIVE: It has been reported that LZD-resistant Enterococcus in the gastrointestinal tract of mice colonizes persistently and shows variable minimum inhibitor concentration (MIC) values. However, the colonization characteristics of Enterococcus with LZD resistance in patients remain elusive. Here, we report the case of a patient with recurrent pneumonia due to infection with LZD-resistant Enterococcus faecalis strains. The colonization characteristics of the strains isolated from this patient were analyzed. METHODS: Ten E. faecalis strains were isolated from tracheal secretions obtained from the patient during five recurrences of pneumonia over the course of 10 months. Clonal relationships were determined by pulsed-field gel electrophoresis (PFGE) with SmaI-macrorestricted genomic DNA. The susceptibility of the isolates to LZD was determined by Etest in Mueller-Hinton agar. RESULTS: The homology of these strains was demonstrated by PFGE, suggesting that occult bacterial colonization by LZD-resistant E. faecalis is possible as late as a year after exposure to LZD. These strains showed variable MICs as determined by the Etest. LZD-resistant isolates contained single or double nucleotide mutations in domain V of 23S rRNA as confirmed by PCR and sequencing. The sensitivity of the strains to vancomycin was demonstrated by broth macrodilution, and vancomycin was an effective clinical treatment on each occasion. CONCLUSIONS: Our results indicate that LZD-resistant E. faecalis strains may colonize persistently in vivo, leading to recurrent infection.

Complete genome sequencing and comparative analysis of the linezolid-resistant Enterococcus faecalis strain DENG1.

Genome level analysis of bacterial strains provides information on genetic composition and resistance mechanisms to clinically relevant antibiotics. To date, whole genome characterization of linezolid-resistant Enterococcus faecalis isolated in the clinic is lacking. In this study, we report the entire genome sequence, genomic characteristics and virulence factors of a pathogenic E. faecalis strain, DENG1. Our results showed considerable differences in genomic characteristics and virulence factors compared with other E. faecalis strains (V583 and OG1RF). The genome of this LZD-resistant E. faecalis strain can be used as a reference to study the mechanism of LZD resistance and the phylogenetic relationship of E. faecalis strains worldwide.