Prevalent Health Problems among Nepalese Underground Construction Workers.

Background: Workplace is associated with exposure to various products, which can be associated with adverse health outcomes. It is true with underground construction work. This study calculated the prevalence of common health problems among Nepalese underground construction workers in comparison to heavy construction workers. This type of study is rare in the context of Nepal and other developing countries, and we hope that the findings will help to take precautions for the prevention of these conditions. Method: It was a retrospective study based on the clinical record of outpatient cases and general health checkups of all Nepalese workers available at the Project clinic, Upper Tamakoshi Hydroelectric Project, Gongar, Bigu, Dolakha. We studied three hundred and ninety-eight workers. We used multipurpose analysis and conducted the Chi-square test and calculated correlations and odds ratios. Results: Two hundred and sixteen (54.3%) participants worked inside the tunnel, and 182 (43.2%) participants worked outside the tunnel. Respiratory disease, mainly upper respiratory tract infection (URTI) (23.4%), is the most common presentation among construction workers followed by injuries (16.7%). Injuries and hypertension were significantly higher in inside the tunnel workers, and acute gastroenteritis was significantly (p value <0.05) higher in outside the tunnel workers. Increasing age increased the chance of hypertension and cutaneous fungal infection among construction workers. Further studies are required for the analysis of risk factors associated with these health conditions. Conclusion: Respiratory problems are the most common health problem in underground construction workers; however, injuries and hypertension were significantly higher in tunnel workers. Acute gastroenteritis was significantly higher among outside the tunnel workers. Workplace safety should be the priority of every construction site, especially focusing to prevent respiratory problems, injuries, and accidents.

Protective effects of Pogostemon cablin Bentham water extract on inflammatory cytokine expression in TNBS-induced colitis in rats.

In inflammatory bowel disease (IBD), colon epithelial cells express a variety of inflammatory mediators, including chemokines, which perpetuate inflammatory response. In the current study, we report that water extract of Pogostemon cablin Bentham aerial parts (PCW), which has traditionally been used for treatment of the common cold and infectious disease, suppressed colon inflammation. Treatment with PCW resulted in effective inhibition of tumor necrosis factor (TNF)-α-induced adhesion of monocytes to HT-29 human colonic epithelial cells. In a trinitrobenzene sulfonic acid (TNBS)-induced rat model of IBD, PCW suppressed clinical signs of colitis, including weight loss, colon tissue myeloperoxidase activity, a marker for inflammatory cell infiltration, and cyclooxygenase-2 expression in a dose-dependent manner. In addition, PCW suppressed TNBS-induced mRNA expression of IL-8, MCP-1, and IL-6 in rat colon. The nuclear level of NF-κB in TNBS-treated rat colon and NF-κB luciferase reporter gene activity in TNF-α-treated HT-29 cells were significantly inhibited by PCW. Taken together, the results of this study suggest that PCW suppressed colon inflammation via suppression of NF-κB-dependent expression of pro-inflammatory cytokines.

Low concentrations of honey reduce biofilm formation, quorum sensing, and virulence in Escherichia coli O157:H7.

Bacterial biofilms are associated with persistent infections due to their high resistance to antimicrobial agents. Hence, controlling pathogenic biofilm formation is important in bacteria-related diseases. Honey, at a low concentration of 0.5% (v/v), significantly reduced biofilm formation in enterohemorrhagic Escherichia coli O157:H7 without inhibiting the growth of planktonic cells. Conversely, this concentration did not inhibit commensal E. coli K-12 biofilm formation. Transcriptome analyses showed that honey significantly repressed curli genes (csgBAC), quorum sensing genes (AI-2 importer and indole biosynthesis), and virulence genes (LEE genes). Glucose and fructose in the honeys were found to be key components in reducing biofilm formation by E. coli O157:H7 through the suppression of curli production and AI-2 import. Furthermore, honey, glucose and fructose decreased the colonization of E. coli O157:H7 cells on human HT-29 epithelial cells. These results suggest that low concentrations of honey, such as in honeyed water, can be a practical means for reducing the colonization and virulence of pathogenic E. coli O157:H7.

Differences in clinical features according to Boryoung and Karp genotypes of Orientia tsutsugamushi.

BACKGROUND: Scrub typhus is an infectious disease caused by Orientia tsutsugamushi. The differences in virulence of O. tsutsugamushi prototypes in humans are still unknown. We investigated whether there are any differences in the clinical features of the Boryoung and Karp genotypes. METHODOLOGY/PRINCIPAL FINDINGS: Patients infected with O. tsutsugamushi, as Boryoung and Karp clusters, who had visited 6 different hospitals in southwestern Korea were prospectively compared for clinical features, complications, laboratory parameters, and treatment responses. Infected patients in the Boryoung cluster had significantly more generalized weakness, eschars, skin rashes, conjunctival injection, high albumin levels, and greater ESR and fibrinogen levels compared to the Karp cluster. The treatment response to current antibiotics was significantly slower in the Karp cluster as compared to the Boryoung cluster. CONCLUSION: The frequency of occurrence of eschars and rashes may depend on the genotype of O. tsutsugamushi.

NADPH oxidase inhibitors: a patent review.

INTRODUCTION: NADPH oxidases, a family of multi-subunit enzyme complexes, catalyze the production of reactive oxygen species (ROS), which may contribute to the pathogenesis of a variety of diseases. In addition to the first NADPH oxidase found in phagocytes, four non-phagocytic NADPH oxidase isoforms have been identified, which all differ in their catalytic subunit (Nox1-5) and tissue distribution. AREAS COVERED: This paper provides a comprehensive review of the patent literature on NADPH oxidase inhibitors, small molecule Nox inhibitors, peptides and siRNAs. EXPERT OPINION: Since each member of the NADPH oxidase family has great potential as a therapeutic target, several different compounds have been registered as NADPH oxidase inhibitors in the patent literature. As yet, none have gone through clinical trials, and some have not completed preclinical trials, including safety and specificity evaluation. Recently, small molecule pyrazolopyridine and triazolopyrimidine derivatives have been submitted as potent NADPH oxidase inhibitors and reported as first-in-class inhibitors for idiopathic pulmonary fibrosis and acute stroke, respectively. Further clinical efficacy and safety data are warranted to prove their actual clinical utility.

Tumor necrosis factor-α and mortality in patients infected with Vibrio vulnificus.

Serum tumor necrosis factor-α (TNF-α) was evaluated in Vibrio vulnificus-infected patients at admission. The median TNF-α concentration in the non-survivor group was determined to be 261.0 pg/mL, in contrast to 69.5 pg/mL in the survivor group (P = 0.001). Hence, serum TNF-α concentration may potentially be an early predictor of the mortality in patients with Vibrio septicemia.

Phylogenetic analysis of the 56 kDa protein genes of Orientia tsutsugamushi in Southwest Area of Korea.

This study was conducted to determine which genotypes were present in southwestern Korea. Nested polymerase chain reaction (PCR) and DNA sequence analysis targeting the Orientia tsutsugamushi-specific 56-kDa protein gene was performed with samples of blood and eschar. Of the 69 PCR-positive samples, 61 clustered with the Boryong previously isolated in Korea. CUH 4-6 had sequence homology of 100% with Kato, and CUH 4-3 had homology of 99.8% with Kato and formed the Kato cluster. CUH 4-57, CUH 4-31, CUH 4-142, and CUH 4-324 formed a Kawasaki cluster. CUH 4-271 had sequence homology of 100% with Jecheon and formed a Karp cluster. CUH 4-117 had homology of 99.8% with Neimeng-65, and Gilliam cluster. The most common genotype of O. tsutsugamushi in the southwestern part of Korea is the Boryong genotype. We also identified O. tsutsugamushi of the Kato, Neimeng-65 and Kawasaki genotypes, which had not been identified before in Korea.

Comparison of conventional, nested, and real-time quantitative PCR for diagnosis of scrub typhus.

Orientia tsutsugamushi is the causative agent of scrub typhus. For the diagnosis of scrub typhus, we investigated the performances of conventional PCR (C-PCR), nested PCR (N-PCR), and real-time quantitative PCR (Q-PCR) targeting the O. tsutsugamushi-specific 47-kDa gene. To compare the detection sensitivities of the three techniques, we used two template systems that used plasmid DNA (plasmid detection sensitivity), including a partial region of the 47-kDa gene, and genomic DNA (genomic detection sensitivity) from a buffy coat sample of a single patient. The plasmid detection sensitivities of C-PCR, N-PCR, and Q-PCR were 5 × 10(4) copies/µl, 5 copies/µl, and 50 copies/µl, respectively. The results of C-PCR, N-PCR, and Q-PCR performed with undiluted genomic DNA were negative, positive, and positive, respectively. The genomic detection sensitivities of N-PCR and Q-PCR were 64-fold and 16-fold (crossing point [Cp], 37.7; 426 copies/µl), respectively. For relative quantification of O. tsutsugamushi bacteria per volume of whole blood, we performed real-time DNA PCR analysis of the human GAPDH gene, along with the O. tsutsugamushi 47-kDa gene. At a 16-fold dilution, the copy number and genomic equivalent (GE) of GAPDH were 1.1 × 10(5) copies/µl (Cp, 22.64) and 5.5 × 10(4) GEs/µl, respectively. Therefore, the relative concentration of O. tsutsugamushi at a 16-fold dilution was 0.0078 organism/one white blood cell (WBC) and 117 organisms/µl of whole blood, because the WBC count of the patient was 1.5 × 10(4) cells/µl of whole blood. The sensitivities of C-PCR, N-PCR, and Q-PCR performed with blood samples taken from patients within 4 weeks of onset of fever were 7.3% (95% confidence interval [CI], 1.6 to 19.9), 85.4% (95% CI, 70.8 to 94.4), and 82.9% (95% CI, 67.9 to 92.8), respectively. All evaluated assays were 100% specific for O. tsutsugamushi. In conclusion, given its combined sensitivity, specificity, and speed, Q-PCR is the preferred assay for the diagnosis of scrub typhus.

Vibrio vulnificus DNA load and mortality.

We determined the association between DNA load and mortality in patients with Vibrio vulnificus infection. Real-time PCR performed on sera of 27 culture-positive patients showed a significantly higher median DNA load in nonsurvivors than in survivors. Hence, real-time PCR can be used as an early prognostic factor in V. vulnificus septicemia.

Enterobacter nimipressuralis as a cause of pseudobacteremia.

BACKGROUND: The clinical significance of the Enterobacter nimipressuralis as human pathogens remains unclear. CASE PRESENTATIONS: The microbiologic culture monitoring system of sterile body fluids revealed on an episode of Enterobacter cloacae and Enterobacter amnigenus in blood culture results on the same day; the antibiotic sensitivity and MIC were nearly the same for both species. First patient was a healthy woman with postmenopausal syndrome, while second patient with herpes zoster. Both patients had febrile sensations without signs of bacteremia. E. amnigenus was also cultured from the unused package of salined cotton in the container through epidemiologic investigation. The cultured Enterobacter species were all identified as E. nimipressuralis through hsp60 gene sequencing and infrequent-restriction-site PCR (IRS-PCR). CONCLUSION: When an unusual microorganisms such as E. nimipressuralis is isolated from blood of a patient with no clinical signs of sepsis, a pseudobacteremia should be suspected. When the antibiogram and MIC test results of bacterial cultures from two or more patients are nearly the same, although the species involved may appear different, it may be necessary to prove that they are the same species through molecular methods. The microbiologic cultures monitoring system will probably help to detect pseudobacteremia and other pseudo infections through reliable and fast identification.

In vitro synergism of ciprofloxacin and cefotaxime against nalidixic acid-resistant Salmonella enterica serotypes Paratyphi A and Paratyphi B.

Paratyphoid fever is considered an emerging systemic intracellular infection caused by Salmonella enterica serotypes Paratyphi A, B, and C. We performed in vitro time-kill studies on three clinical isolates of nalidixic acid-resistant Salmonella serotype Paratyphi (NARSP) with different concentrations of ciprofloxacin and cefotaxime to identify combinations of antibiotics with synergistic activity against paratyphoid fever. Furthermore, we identify the frequency of mutations to ciprofloxacin, cefotaxime, and rifampin resistance and also sequenced the gyrA, gyrB, parC, and parE genes to identify the cause of resistance in NARSP. When the activity of ciprofloxacin at 0.75x MIC (0.012 to 0.38 microg/ml) with cefotaxime at the MIC (0.125 to 0.25 microg/ml) against all three NARSP isolates was investigated, synergy was observed at 24 h, and the bacterial counts were reduced by >3 log(10) CFU/ml. This synergy was elongated for up to 72 h in two out of three isolates. When ciprofloxacin at 0.75x MIC (0.012 to 0.38 microg/ml) was combined with cefotaxime at 2x MIC (0.25 to 0.50 microg/ml), synergy was prolonged for up to 72 h in all three isolates. Both Salmonella serotype Paratyphi A isolates carried single mutations in codon 83 of the gyrA gene and codon 84 of the parC gene that were responsible for their reduced susceptibility to ciprofloxacin, while no mutations were found in the gyrB or parE gene. The ciprofloxacin-plus-cefotaxime regimen was very effective in reducing the bacterial counts at 24 h for all three isolates, and this combination therapy may be helpful in reducing the chance of the emergence of fluoroquinolone-resistant mutants in patients with severe paratyphoid fever.

In vitro efficacy of the combination of ciprofloxacin and cefotaxime against nalidixic acid-resistant Salmonella enterica serotype Typhi.

Typhoid fever is a systemic intracellular infection caused by Salmonellaenterica serotype Typhi. The emergence and spread of nalidixic acid-resistant S. Typhi (NARST) is challenging for clinicians in many countries owing to the lack of suitable treatment options. The aim of this study was to identify in vitro synergistic combinations of antibiotics against S. Typhi. In vitro time-kill studies were performed on three clinical NARST isolates and one type strain of nalidixic acid-susceptible S. Typhi (NASST) ATCC 9992 with ciprofloxacin, cefotaxime and azithromycin in various combinations. The combination of ciprofloxacin (0.012-0.375 microg/mL) and cefotaxime (0.063-0.125 microg/mL) against all three NARST strains and the NASST strain was significantly more effective in vitro in reducing bacterial counts by >or=3log(10) colony-forming units at 24h and showed synergistic effects. Combination therapy with ciprofloxacin and cefotaxime might be the treatment of choice for patients with typhoid fever. The combination of a fluoroquinolone and a beta-lactam, which are directed against different targets, may improve efficacy compared with a fluoroquinolone alone and may reduce the chance of fluoroquinolone-resistant mutants emerging in patients with severe typhoid fever.

Comparison of the effects of deferasirox, deferiprone, and deferoxamine on the growth and virulence of Vibrio vulnificus.

BACKGROUND: Since deferoxamine (DFO), a standard iron-chelating agent that is widely used in patients with iron overload such as hemochromatosis or thalassemia, is a kind of hydroxamine siderophore of Streptomyces species, it can accelerate the in vitro growth of ferophilic organisms such as Vibrio vulnificus, Yersinia enterocolitica, and Mucorales. STUDY DESIGN AND METHODS: We compared the effects of the two oral iron chelators, deferiprone (DFP) and deferasirox (DFS), on the growth and virulence of V. vulnificus with that of the parenteral iron-chelating drug DFO used to treat patients with iron overload. RESULTS: When V. vulnificus ATCC 27562 was grown in iron-poor liquid medium with α,α'-dipryridyl, addition of DFO promoted its growth, whereas DFP and DFS did not. Only DFP and DFS showed growth inhibitory effect by chelating iron and causing iron deprivation. Similarly, on iron-poor agar plates, various clinical V. vulnificus strains were only able to grow around filter paper disks impregnated with DFO. Our in vitro study data showed that DFS or DFP has more potential clinical application for preventing V. vulnificus infection in patients receiving iron chelation therapy. CONCLUSIONS: When patients with iron overload need iron chelation therapy, especially in a population at high risk for V. vulnificus in its endemic season, DFS or DFP may be safely used rather than DFO.

Comparison of conventional, nested, and real-time PCR assays for rapid and accurate detection of Vibrio vulnificus.

We conducted a prospective study to target toxR in the blood of patients with skin and soft tissue infections who were admitted to four tertiary hospitals to assess the clinical usefulness of real-time quantitative PCR (Q-PCR) as a diagnostic technique. We performed conventional PCR (C-PCR), nested PCR (N-PCR), and Q-PCR assays and compared the results to those obtained using the "gold standard" of microbiological culture. The lower detection limit for the Q-PCR assay was 5 x 10(0) copies/microl. By use of blood samples of patients with skin and soft tissue infections, the sensitivities of the C-PCR and N-PCR assays against the target toxR gene of V. vulnificus as diagnostic tools were determined to be 45% and 86%, respectively. The C-PCR and N-PCR assays had specificities of 100% and 73%, respectively. When we adopted a crossing-point (cp) cutoff value of <38 cp as a positive result, the Q-PCR assay had 100% sensitivity and specificity. Q-PCR to detect V. vulnificus-specific genes is not only the most sensitive and specific of the techniques but also the most rapid diagnostic method. Therefore, the appropriate application of the Q-PCR assay using blood is useful for the rapid diagnosis and subsequent treatment of V. vulnificus sepsis.