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Prostate cancer (PC) is the most common cancer diagnosed in men worldwide. Currently, castration-resistant prostate cancer (CRPC), which is resistant to androgen deprivation therapy, has a poor prognosis and is a therapeutic problem. We investigated the antitumor effects on PC of an antibody neutralizing secreted disintegrin and metalloproteinase domain-containing protein 9 (sADAM9), which is a blood-soluble form. We performed proliferation assays, wound healing assays, invasion assays, Western blot (WB), and an in vivo study in which a sADAM9 neutralizing antibody was administered intratumorally to PC-bearing mice. In invasion assays, the sADAM9 neutralizing antibody significantly inhibited invasion in all cell lines (TRAMP-C2: p = 0.00776, LNCaP: p = 0.000914, PC-3: p = 0.0327, and DU145: p = 0.0254). We examined epithelial–mesenchymal transition (EMT) markers, one of the metastatic mechanisms, in WB and showed downregulation of Slug in TRAMP-C2, LNCaP, and DU145 and upregulation of E-cadherin in TRAMP-C2 and PC-3 by sADAM9 neutralization. In mouse experiments, the sADAM9 neutralizing antibody significantly suppressed tumor growth compared to controls (1.68-fold in TRAMP-C2, 1.89-fold in LNCaP, and 2.67-fold in PC-3). These results suggested that the sADAM9 neutralizing antibody inhibits invasion, migration, and tumor growth in PC. Previous studies examined the anti-tumor effect of knockdown of total ADAM9 or sADAM9, but this study used the new technology of neutralizing antibodies for sADAM9. This may be novel because there was no animal study using a neutralizing antibody for sADAM9 to see the relationship between ADAM9 expression and prostate cancer. [ABSTRACT FROM AUTHOR]

Protein oligomerization occurs frequently both in vitro and in vivo, with specific functionalities associated with different oligomeric states. The YqiC protein from Salmonella Typhimurium forms a homotrimer through its C‐terminal coiled‐coil domain, and the protein is closely linked to the colonization and invasion of the bacteria to the host cells. To elucidate the importance of the oligomeric state of YqiC in vivo and its relation with bacterial infection, we mutated crucial residues in YqiC's coiled‐coil region and confirmed the loss of trimer formation using chemical crosslinking and size exclusion chromatography coupled with multiple angle light scattering (SEC‐MALS) techniques. The yqiC‐knockout strain complemented with mutant YqiC showed significantly reduced colonization and invasion of Salmonella to host cells, demonstrating the critical role of YqiC oligomerization in bacterial pathogenesis. Furthermore, we conducted a protein–protein interaction study of YqiC using a pulled‐down assay coupled with mass spectrometry analysis to investigate the protein's role in bacterial virulence. The results reveal that YqiC interacts with subunits of Complex II of the electron transport chain (SdhA and SdhB) and the β‐subunit of F0F1‐ATP synthase. These interactions suggest that YqiC may modulate the energy production of Salmonella and subsequently affect the assembly of crucial virulence factors, such as flagella. Overall, our findings provide new insights into the molecular mechanisms of YqiC's role in S. Typhimurium pathogenesis and suggest potential therapeutic targets for bacterial infections. [ABSTRACT FROM AUTHOR]

Carbapenem-resistant Klebsiella pneumoniae (CRKP) is a life-threatening pathogen that has not been fully investigated on a molecular basis. Therefore, the molecular mechanisms of carbapenem resistance in CRKP collected from medical institutions in Hyogo Prefecture has been analyzed. Antimicrobial susceptibilities and the presence of carbapenemase along with epidemiological analyzes using multilocus sequence typing (MLST) have been investigated. The relative expression of efflux pump genes and mutations of ompK35 and ompK36 , encoding the outer membrane porin, were also assessed for their relationship with carbapenem resistance. Most of the collected 22 CRKP isolates were non-susceptible to imipenem (68.2%), meropenem (90.9%), and ertapenem (81.8%), but all 22 strains were susceptible to colistin. Twelve strains (54.5%) were detected for carbapenemase genes such as bla IMP-6. Sequence type 37 was detected by MLST in 10 strains (45.5%). Non-carbapenemase-producing strains had high resistance rates for three carbapenems, and the main cause of resistance was ompK35 mutation. In conclusion, the main cause of resistance was imipenemase metallo-β-lactamase (IMP-6) production in carbapenemase-producing strains, and ompK35 mutation in non-carbapenemase-producing strains. Susceptibility to carbapenem did not differ in CRKP regardless of carbapenemase production, except for imipenem susceptibility. This result contributes to a more insightful understanding of the mechanisms of CRKP in Japan. [ABSTRACT FROM AUTHOR]

Objective: We report the impact of the COVID‐19 pandemic on urological surgeries and hospital policies at two hospitals in Japan and Taiwan. Methods: We retrospectively surveyed the number of surgeries every 3 months in the Urology Department of Kobe University Hospital (KUH), Kobe, Japan before (January 2019–March 2020) and after (April 2020–September 2021) the COVID‐19 outbreak, and in the Urology Department of Shuang Ho Hospital, Taipei Medical University (SHH‐TMU), Taiwan before (January 2021–March 2021) and after (April 2021–September 2021) the outbreak, and compared the averages and types of surgery. Results: In Kobe, COVID‐19 patients were stratified such that other regional hospitals gave priority to treating COVID‐19 while KUH gave priority to treating non‐COVID‐19 patients. In KUH, the number of surgeries did not change significantly, 237.2 ± 29.6 versus 246.3 ± 20.8 (p = 0.453). In Taiwan COVID‐19 patients increased sharply in May 2021, and teaching hospitals in Taiwan were obliged to provide 20% of their total beds for COVID‐19 patients. At SHH‐TMU, there was a 33.3% drop in the number of surgeries during April–June 2021 compared to the pre‐pandemic average. However, no significant changes were observed, 423.4 ± 68.4 versus 373 ± 91.0 (p = 0.298), because of the subsequent success in controlling the COVID‐19 infection. Conclusions: The comparison of infection control measures between the two countries revealed that while both KUH and SHH‐TMU successfully maintained the number of surgeries, the reasons for this were different for each. [ABSTRACT FROM AUTHOR]

Klebsiella pneumoniae is a typical pathogen in urinary tract infections (UTI), and the emergence of extended spectrum beta-lactamase (ESBL)-producing strains has been frequently reported, accompanied by higher quinolone resistance rates. There are two major mechanisms of quinolone resistance, mutations in quinolone resistance-determining regions (QRDR) and the presence of the plasmid-mediated quinolone resistance (PMQR) genes. This study aimed to investigate quinolone resistance among 105 ESBL-producing K. pneumoniae specimens isolated from UTI patients in Indonesia. These were characterized for antimicrobial resistance to nalidixic acid, ciprofloxacin, and levofloxacin, QRDR mutations in gyrA and parC and the presence of PMQR genes. We found that 84.8% of the collected isolates were resistant to at least one of the quinolones. QRDR mutation in gyrA was observed in 49.5% of these strains and parC mutations in 61.0%. PMQR genes were identified in 84.8% of strains. The QRDR mutations clearly had a greater effect on resistance than the PMQR genes. In conclusion, we found high quinolone resistance rates in Indonesian ESBL-producing K. pneumoniae , in which QRDR mutation played a major role. [ABSTRACT FROM AUTHOR]

Microfold or membranous (M) cells are specialized intestinal epithelial cells responsible for host immunity. The speG mutant of Salmonella Typhimurium (S. Typhimurium) is a nonreplicating strain within human cells to be a candidate vaccine vector for interacting with M cells. We conducted this study to identify the genes are differently expressed between in vitro M cells and Caco-2 cells, and to determine whether S. Typhimurium and speG affect the transcriptomes of both cell types. In vitro M cells and Caco-2 cells were infected with wild-type (WT) S. Typhimurium, its ΔspeG mutant, or none for 1 h for RNA microarrays; the transcriptomes among the 6 pools were pairwisely compared. Genetic loci encoding scaffold (e.g., HSCHR7_CTG4_4, HSCHR9_CTG9_35), long noncoding RNA, membrane-associated protein (PITPNB), neuron-related proteins (OR8D1, OR10G9, and NTNG2), and transporter proteins (MICU2 and SLC28A1) were significantly upregulated in uninfected M cells compared with uninfected Caco-2 cells; and their encoding proteins are promising M-cell markers. Significantly upregulated HSCHR7_CTG4_4 of uninfected in vitro M cells were speG-independently downregulated by S. Typhimurium infection that is a remarkable change representing an important but unreported characteristic of M cells. The immune responses of in vitro M cells and Caco-2 cells can differ and reply on speG or not, with speG-dependent regulation of KYL4, SCTR, IL6, TNF, and CELF4 in Caco-2 cells, JUN, KLF6, and KCTD11 in M cells, or speG-independent modulation of ZFP36 in both cells. This study facilitates understanding of the immune responses of in vitro M cells after administering the S. Typhimurium ΔspeG mutant as a future vaccine vector. [ABSTRACT FROM AUTHOR]

Background: yqiC is required for colonizing the Salmonella enterica serovar Typhimurium (S. Typhimurium) in human cells; however, how yqiC regulates nontyphoidal Salmonella (NTS) genes to influence bacteria–host interactions remains unclear. Methods: The global transcriptomes of S. Typhimurium yqiC-deleted mutant (ΔyqiC) and its wild-type strain SL1344 after 2 h of in vitro infection with Caco-2 cells were obtained through RNA sequencing to conduct comparisons and identify major yqiC-regulated genes, particularly those involved in Salmonella pathogenicity islands (SPIs), ubiquinone and menaquinone biosynthesis, electron transportation chains (ETCs), and carbohydrate/energy metabolism. A Seahorse XFp Analyzer and assays of NADH/NAD+ and H2O2 were used to compare oxygen consumption and extracellular acidification, glycolysis parameters, adenosine triphosphate (ATP) generation, NADH/NAD+ ratios, and H2O2 production between ΔyqiC and SL1344. Results: After S. Typhimurium interacts with Caco-2 cells, yqiC represses gene upregulation in aspartate carbamoyl transferase, type 1 fimbriae, and iron–sulfur assembly, and it is required for expressing ilvB operon, flagellin, tdcABCD, and dmsAB. Furthermore, yqiC is required for expressing mainly SPI-1 genes and specific SPI-4, SPI-5, and SPI-6 genes; however, it diversely regulates SPI-2 and SPI-3 gene expression. yqiC significantly contributes to menD expression in menaquinone biosynthesis. A Kyoto Encyclopedia of Genes and Genomes analysis revealed the extensive association of yqiC with carbohydrate and energy metabolism. yqiC contributes to ATP generation, and the analyzer results demonstrate that yqiC is required for maintaining cellular respiration and metabolic potential under energy stress and for achieving glycolysis, glycolytic capacity, and glycolytic reserve. yqiC is also required for expressing ndh, cydA, nuoE, and sdhB but suppresses cyoC upregulation in the ETC of aerobically and anaerobically grown S. Typhimurium; priming with Caco-2 cells caused a reversed regulation of yiqC toward upregulation in these ETC complex genes. Furthermore, yqiC is required for maintaining NADH/NAD+ redox status and H2O2 production. Conclusions: Specific unreported genes that were considerably regulated by the colonization-associated gene yqiC in NTS were identified, and the key role and tentative mechanisms of yqiC in the extensive modulation of virulence factors, SPIs, ubiquinone and menaquinone biosynthesis, ETCs, glycolysis, and oxidative stress were discovered. [ABSTRACT FROM AUTHOR]

Purpose: This study investigates whether post-chemotherapeutic use of live and heat-killed Lactobacillus rhamnosus GG can modulate the expression of three pro-inflammatory cytokines in 5-fluorouracil (5-FU)-induced intestinal mucositis in vitro. Methods: Live L. rhamnosus GG and heat-killed L. rhamnosus GG were observed using scanning electron microscopy. To establish the duration required for optimal expression of tumor necrosis factor-α (TNF-α), monocyte chemotactic protein-1 (MCP-1), and interleukin-12 (IL-12), 5 μM of 5-FU was selected to treat 10-day-old Caco-2 cells for 4, 6, 8, and 24 h. Caco-2 cells were treated with 5-FU (5 μM) for 4 h, followed by the administration of live L. rhamnosus GG (multiplicity of infection = 25), and heat-killed L. rhamnosus GG for 2 and 4 h. Finally, total cellular RNA was isolated to quantify mRNA expression of TNF-α, MCP-1, and IL-12 using real-time PCR. Results: The results demonstrated that heat-killed L. rhamnosus GG remained structurally intact with elongation. A biphasic upregulated expression of TNF-α, MCP-1, and IL-12 was observed in 5-FU-treated Caco-2 cells at 4 and 24 h. Compared to non- L. rhamnosus GG controls in 5-FU-pretreated Caco-2 cells, a 2-h treatment of heat-killed L. rhamnosus GG significantly upregulated the MCP-1 expression ( p < 0.05), and both live and heat-killed L. rhamnosus GG treatments lasting 4 h upregulated the TNF-α and MCP-1 expression ( p < 0.05). Only live L. rhamnosus GG upregulated the IL-12 expression ( p < 0.05). Conclusions: Post-chemotherapeutic use of live or heat-killed L. rhamnosus GG can upregulate the gene expression of 5-FU-induced pro-inflammatory cytokines in Caco-2 cells. Human intestinal epithelium may be vulnerable to the post-chemotherapeutic use of L. rhamnosus GG in 5-FU-induced mucositis that requires further in vivo studies for clarification. [ABSTRACT FROM AUTHOR]

Aims: The aim was to investigate conjugated and unconjugated hyperbilirubinaemia in association with urinary tract infection (UTI) in young infants. Methods: Fifty infants aged <3 mths who developed prolonged jaundice among 2128 infants with UTI from 1984 to 2004 were enrolled retrospectively. They were divided into conjugated (n=22) and unconjugated (n=28) hyperbilirubinaemia groups and the clinical variables between the two were compared. Results: Compared with the unconjugated group, the conjugated hyperbilirubinaemia group had statistically significantly lower haemoglobin (1.57 vs 1.80 m mol/L), higher aspartate aminotransferase (96 vs 32.5 U/L) and alanine aminotransferase (81.5 vs 16 U/L), were older on admission (48.0 vs 32.5 days), had a longer duration of jaundice before treatment (43.5 vs 30 days) and a higher incidence of E. coli infections (19/22 vs 15/28). The direct/total bilirubin ratio was linearly correlated with duration of jaundice before treatment (p=0.004). The most significant cut-off value for the duration of jaundice vis-à-vis the type of jaundice was 38 days (p=0.007). Patients who on presentation had had jaundice for >44 days (p=0.007) were unlikely to have unconjugated hyperbilirubinaemia. Conclusions: Infants with UTI may present with unconjugated hyperbilirubinaemia in the early stage. After 6 weeks, it is always conjugated hyperbilirubinaemia and is frequently associated with anaemia, elevated hepatic aminotransferases and E. coli infections. [ABSTRACT FROM AUTHOR]

It is difficult to distinguish clinically between bacterial and viral causes of enterocolitis. The aim of the study was to investigate if serum cytokines can distinguish bacterial from viral enterocolitis. We prospectively enrolled 147 paediatric in-patients with acute enterocolitis. Blood was taken for leucocyte count, CRP, ESR, IL-6, IL-8, IFN- a and TNF- a on the day of admission. A pathogen was identified in 115 of the 147 children, 72 of whom had a bacterial pathogen (bacterial group) and 43 rotavirus (viral group). Mean values of the serum markers IL-6, IL-8 and CRP were significantly higher in the bacterial group. Receiver-operating characteristic curves demonstrated that a cut-off of 15 pg/ml for IL-6 had a sensitivity of 0.75 and a specificity of 0.91 for bacterial diarrhoea. Comparable values for CRP at a cut-off of 13 mg/L demonstrated a sensitivity of 0.54 and a specificity of 0.72. Values for IL-8 at a cut-off of 80 pg/ml had a sensitivity of 0.46 and a specificity of 0.71. Despite the small sample size, our data suggest that serum IL-6, IL-8 and CRP are significantly elevated in children with bacterial enterocolitis. IL-6 has a higher sensitivity, specificity and positive predictive value than IL-8 and CRP. Determination of serum cytokines might be a useful way of differentiating viral from bacterial gastro-enteritis. [ABSTRACT FROM AUTHOR]

Imipenemase-6 (IMP-6) type carbapenemase-producing Enterobacteriaceae is regarded as dangerous due to its unique lack of antimicrobial susceptibility. It is resistant to meropenem (MEPM) but susceptible to imipenem (IPM). In addition to carbapenemase, outer membrane porins and efflux pumps also play roles in carbapenem resistance by reducing the antimicrobial concentration inside cells. Extended-spectrum β-lactamase (ESBL) is transmitted with IMP-6 by the plasmid and broadens the spectrum of antimicrobial resistance. We collected 42 strains of IMP-6-producing Escherichia coli and conducted a molecular analysis of carbapenemase, ESBL, porin, efflux, and epidemiological characteristics using plasmid replicon typing. Among the 42 isolates, 21 strains were susceptible to IPM (50.0%) and 1 (2.4%) to MEPM. Seventeen strains (40.5%) co-produced CTX-M-2 type ESBL. We found that the relative expression of ompC and ompF significantly correlated with the MIC of IPM (p = 0.01 and p = 0.03, respectively). Sixty-eight% of CTX-M-2-non-producing strains had IncI1, which was significantly different from CTX-M-2-producing strains (p < 0.001). In conclusion, 50.0% of our IMP-6-producing strains were non-susceptible to IPM, which is different from the typical pattern and can be attributed to decreased porin expression. Further studies investigating other types of carbapenemase are warranted. [ABSTRACT FROM AUTHOR]

This study analyzed the genetic diversity of ciprofloxacin (CIP) nonsusceptibility and the relationship between two major mechanisms and minimum inhibitory concentrations (MICs) of CIP in nontyphoidal Salmonella (NTS). Chromosomal mutations in quinolone resistance-determining regions (QRDRs) and plasmid-mediated quinolone resistance (PMQR) genes were searched from ResFinder, ARG-ANNOT, and PubMed for designing the sequencing regions in gyrA, gyrB, parC, and parE, and the 13 polymerase chain reactions for PMQR genes. We found that QRDR mutations were detected in gyrA (82.1%), parC (59.0%), and parE (20.5%) but not in gyrB among the 39 isolates. Five of the 13 PMQR genes were identified, including oqxA (28.2%), oqxB (28.2%), qnrS (18.0%), aac(6′)-Ib-cr (10.3%), and qnrB (5.1%), which correlated with the MICs of CIP within 0.25–2 μg/mL, and it was found that oxqAB contributed more than qnr genes to increase the MICs. All the isolates contained either QRDR mutations (53.8%), PMQR genes (15.4%), or both (30.8%). QRDR mutations (84.6%) were more commonly detected than PMQR genes (46.2%). QRDR mutation numbers were significantly associated with MICs (p < 0.001). Double mutations in gyrA and parC determined high CIP resistance (MICs ≥ 4 μg/mL). PMQR genes contributed to intermediate to low CIP resistance (MICs 0.25–2 μg/mL), thus providing insights into mechanisms underlying CIP resistance. [ABSTRACT FROM AUTHOR]

The prevalence of vancomycin resistant enterococcus (VRE) carrier-state has been increasing in patients of intensive care unit and it would be a public health threat. Different research groups conducted decolonizing VRE with probiotic and the results were controversial. Therefore, a systemic approach to search for the probiotic species capable of decolonizing VRE is necessary. Thus, VRE was co-cultured with ten probiotic species. The fluctuations of each bacterial population were analyzed by 16S rRNA sequencing. Microbial network analysis (MNA) was exploited to identify the most critical species in inhibiting the VRE population. The MNA-selected probiotic cocktail was then validated for its efficacy in inhibiting VRE, decolonizing VRE from Caco-2 cells via three approaches: exclusion, competition, and displacement. Finally, the expression of VRE virulence genes after co-incubation with the probiotic cocktail were analyzed with quantitative real-time PCR (qRT-PCR). The MNA-selected probiotic cocktail includes Bacillus coagulans, Lactobacillus rhamnosus GG, Lactobacillus reuteri, and Lactobacillus acidophilus. This probiotic combination significantly reduces the population of co-cultured VRE and prevents VRE from binding to Caco-2 cells by down-regulating several host-adhesion genes of VRE. Our results suggested the potential of this four-strain probiotic cocktail in clinical application for the decolonization of VRE in human gut. [ABSTRACT FROM AUTHOR]

Presents a case of two children with colonic dilatation following Campylobacter enterocolitis. Examination of the colectomy specimen; Significance of the differential diagnosis between infective and non-infective causes of toxic megacolon; Instance when antibiotic therapy can be applied.