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1.
Foods ; 13(13)2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38998565

ABSTRACT

Shiga toxin-producing Escherichia coli (STEC) is one of the most important foodborne pathogens, and the rise of antibiotic resistance to it is a significant threat to global public health. The purpose of this study is to investigate the prevalence, molecular characterization, and antibiotic resistance of STEC isolated from raw meat in Vietnam. The findings in this study showed that the prevalence of STEC in raw beef, pork, and chicken meat was 9.72% (7/72), 5.56% (4/72), and 1.39% (1/72), respectively. The STEC isolates were highly resistant to ampicillin (91.67%) and tetracycline (91.67%), followed by trimethoprim/sulfamethoxazole (83.33%), streptomycin (75%), and florfenicol (66.67%). The incidence of STEC virulence-associated genes, including stx1, stx2, eae, and ehxA, was 8.33% (1/12), 91.67% (11/12), 33.33% (4/12), and 58.33% (7/12), respectively. STEC serogroups O157, O26, and O111 were detected in 3 out of 12 STEC isolates. Two isolates were found to be ESBL producers carrying the blaCTX-M-55 gene, and three isolates were colistin-resistant strains harboring the mcr-1 gene. Notably, a STEC O111 isolate from chicken meat harbored both the blaCTX-M-55 and mcr-1 genes.

2.
Microb Ecol ; 87(1): 85, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38935220

ABSTRACT

Antimicrobial resistance (AMR) is a major public health threat, exacerbated by the ability of bacteria to rapidly disseminate antimicrobial resistance genes (ARG). Since conjugative plasmids of the incompatibility group P (IncP) are ubiquitous mobile genetic elements that often carry ARG and are broad-host-range, they are important targets to prevent the dissemination of AMR. Plasmid-dependent phages infect plasmid-carrying bacteria by recognizing components of the conjugative secretion system as receptors. We sought to isolate plasmid-dependent phages from wastewater using an avirulent strain of Salmonella enterica carrying the conjugative IncP plasmid pKJK5. Irrespective of the site, we only obtained bacteriophages belonging to the genus Alphatectivirus. Eleven isolates were sequenced, their genomes analyzed, and their host range established using S. enterica, Escherichia coli, and Pseudomonas putida carrying diverse conjugative plasmids. We confirmed that Alphatectivirus are abundant in domestic and hospital wastewater using culture-dependent and culture-independent approaches. However, these results are not consistent with their low or undetectable occurrence in metagenomes. Therefore, overall, our results emphasize the importance of performing phage isolation to uncover diversity, especially considering the potential of plasmid-dependent phages to reduce the spread of ARG carried by conjugative plasmids, and to help combat the AMR crisis.


Subject(s)
Bacteriophages , Plasmids , Wastewater , Plasmids/genetics , Wastewater/virology , Wastewater/microbiology , Bacteriophages/genetics , Bacteriophages/isolation & purification , Bacteriophages/physiology , Bacteriophages/classification , Genome, Viral , Escherichia coli/virology , Escherichia coli/genetics , Host Specificity , Pseudomonas putida/virology , Pseudomonas putida/genetics , Salmonella enterica/virology , Salmonella enterica/genetics , Phylogeny
3.
Pathogens ; 13(6)2024 Jun 09.
Article in English | MEDLINE | ID: mdl-38921792

ABSTRACT

E. coli is an important zoonotic pathogen capable of causing foodborne illness and bovine mastitis. Bacteriophages have been increasingly considered a promising tool to control unwanted bacteria. The aim of this study is to determine the antibiotic resistance profile of E. coli isolated from raw milk and the efficacy of phage in controlling multidrug-resistant E. coli in raw milk. Antibiotic susceptibility testing showed the highest resistance rates of E. coli isolates to co-trime (27.34%) and ampicillin (27.34%), followed by streptomycin (25.18%), tetracycline (23.02%), and the lowest resistance rates to ciprofloxacin, gentamycin, and ceftazidime, all at a rate of 2.16%. All isolates were susceptible to meropenem. Of the 139 E. coli isolates, 57 (41.01%) were resistant to at least one antibiotic, and 35 (25.18%) were classified as MDR strains. Molecular characterization indicated that 5 (3.6%) out of the 139 isolates were STEC strains carrying stx1 gene. Seven (5.04%) isolates were phenotypically identified as ESBLEC, and four isolates (2.88%) were resistant to colistin. The results of the genotypic test revealed that four out of seven ESBLEC strains carried both blaTEM and blaCTX-M-1, two harbored blaTEM, and one possessed blaCTX-M-1, while mcr-1 was detected in all four colistin-resistant E. coli isolates. In particular, one isolated E. coli strain (EM148) was determined to be a multidrug-resistant strain simultaneously carrying blaTEM, blaCTX-M-1, and mcr-1. A total of eight phages were successfully recovered from raw milk. The application of phage PEM3 significantly reduced viable counts of multidrug-resistant host EM148 in raw milk by at least 2.31 log CFU/mL at both 24 °C and 4 °C.

4.
Pathogens ; 13(5)2024 May 10.
Article in English | MEDLINE | ID: mdl-38787252

ABSTRACT

Clostridium perfringens is one of the most important zoonotic pathogens as it can cause food poisoning in humans and necrotic enteritis in both animals and humans. Meat, especially pork and chicken meat, is considered the main vehicle for the transmission of C. perfringens from animals to humans. The purpose of this study was to determine the prevalence, toxinotype, and antimicrobial resistance profile of C. perfringens isolated from pork and chicken meat sold in Vietnam. The isolation results showed that 15/50 (30%) of pork samples and 8/50 (16%) of chicken meat samples were contaminated with C. perfringens. The isolates exhibited their highest resistance rate to tetracycline (21/23; 91.30%) and clindamycin (10/23; 43.48%). On the contrary, their lowest resistance rates were observed in response to imipenem (2/23; 8.70%) and cefoxitin (1/23; 4.35%). In particular, 34.78% (8/23) of C. perfringens isolates were identified to be multidrug-resistant strains. The results of toxin genotyping indicated that all isolates were positive for the cpa gene and belonged to type A.

5.
J Public Health Res ; 13(2): 22799036241243269, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38606394

ABSTRACT

Background: The COVID-19 pandemic has emphasized the critical role of public knowledge, attitudes, and practices (KAP) in disease containment. Understanding these aspects can guide health promotion initiatives and policy decisions. Design and methods: This cross-sectional study examined the KAP concerning COVID-19 prevention in Vietnam. Participants' sociodemographic data, along with KAP toward COVID-19, were collected in a survey utilizing a standardized questionnaire. Uni- and multivariable logistic regression were used to identify factors associated with poor level of KAP. Results: Of 335 participants, 97 (28.9%) had poor knowledge, 52 (15.5%) poor attitude, and 48 (14.3%) poor practices. Older age (OR = 2.23; p = 0.024), minority non-Kinh ethnicity (OR = 3.05; p = 0.03), education below high school (OR = 8.80; p < 0.001), limited social media access (OR = 2.86; p = 0.002), and limited mobile phone usage (OR = 3.08; p = 0.001) increased poor knowledge risks. Non-Kinh ethnicity (OR = 5.00; p = 0.005) and lower education (OR = 14.79; p < 0.001) were linked to poor attitude. Older age (OR = 2.26; p = 0.035), lower education (OR = 5.74; p = 0.003), and poor knowledge (OR = 3.33; p = 0.005) were associated with poor practices. Conclusions: Elderly individuals, those with low education, and limited media access had elevated risks of poor KAP. Emphasizing public health media and targeted education, especially for underserved groups, is vital for effective epidemic management and future strategy planning.

6.
Phys Chem Chem Phys ; 26(15): 11825-11832, 2024 Apr 17.
Article in English | MEDLINE | ID: mdl-38566602

ABSTRACT

This study investigates the optical absorption of monolayer phosphorene, focusing on its response to the electron-phonon coupling (EPC) and an electric field. Using a tight-binding Hamiltonian model based on the Barisic-Labbe-Friedel-Su-Schrieffer-Heeger model and the Kubo formula, we calculate the electronic band structure and optical absorption characteristics. The anisotropic dispersion of carriers along armchair and zigzag directions leads to distinct optical responses. Positive and negative EPC effects increase and decrease hopping parameters, respectively, enlarging and reducing/closing the band gap. Moreover, both EPCs cause an admixture of blue and red shift spectrum along the armchair direction, while a red (blue) shift spectrum is observed for positive (negative) EPC along the zigzag direction. Incorporating electric field effects in the EPC increases band gaps for both positive and negative EPC activities, resulting in shifted optical peaks along both directions.

7.
Infect Drug Resist ; 17: 259-273, 2024.
Article in English | MEDLINE | ID: mdl-38283112

ABSTRACT

Purpose: Staphylococcus aureus is a commensal bacteria species that can cause various illnesses, from mild skin infections to severe diseases, such as bacteremia. The distribution and antimicrobial resistance (AMR) pattern of S. aureus varies by population, time, geographic location, and hospital wards. In this study, we elucidated the epidemiology and AMR patterns of S. aureus isolated from a general hospital in Vietnam. Methods: This was a cross-sectional study. Data on all S. aureus infections from 2014 to 2021 were collected from the Microbiology department of Military Hospital 103, Vietnam. Only the first isolation from each kind of specimen from a particular patient was analyzed using the Cochran-Armitage and chi-square tests. Results: A total of 1130 individuals were diagnosed as S. aureus infection. Among them, 1087 strains were tested for AMR features. Most patients with S. aureus infection were in the age group of 41-65 years (39.82%). S. aureus isolates were predominant in the surgery wards, and pus specimens were the most common source of isolates (50.62%). S. aureus was most resistant to azithromycin (82.28%), erythromycin (82.82%), and clindamycin (82.32%) and least resistant to teicoplanin (0.0%), tigecycline (0.16%), quinupristin-dalfopristin (0.43%), linezolid (0.62%), and vancomycin (2.92%). Methicillin-resistant S. aureus (MRSA) and multidrug-resistant (MDR) S. aureus were prevalent, accounting for 73.02% and 60.90% of the total strains respectively, and the strains isolated from the intensive care unit (ICU) had the highest percentage of multidrug resistance (77.78%) among the wards. Conclusion: These findings highlight the urgent need for continuous AMR surveillance and updated treatment guidelines, particularly considering high resistance in MRSA, MDR strains, and ICU isolates. Future research focusing on specific resistant populations and potential intervention strategies is crucial to combat this rising threat.

8.
BMC Infect Dis ; 23(1): 802, 2023 Nov 16.
Article in English | MEDLINE | ID: mdl-37974105

ABSTRACT

BACKGROUND: Healthcare utilization is typically adversely affected when the treatment is expensive and requires multiple visits. We examined the determinants of healthcare-seeking for Hepatitis C virus (HCV) infection which is asymptomatic, chronic, and requires costly treatment in an urban tertiary care referral hospital in Vietnam. METHODS: We conducted a secondary analysis of hospital data for patients attending the Hospital for Tropical Diseases in Ho Chi Minh City, Vietnam between 2017 and 2020 specifically for HCV infection treatment. Poisson regression was used to determine the effect of personal factors (age, sex, comorbidities) and structural factors (health insurance, proximity to the facility, seasonality, year of visit) on the number of hospital visits. RESULTS: From 2017 to 2020 a total of 22,052 eligible patients sought treatment in the hospital. Among the patients, 50.4% were males and 58.7% were > 50 years of age. The mean number of visits per person was 2.17. In the multivariate analysis compared to 2017, the number of hospital visits increased by 4% in 2018 and then significantly decreased in 2019 and 2020. Visit numbers were significantly lower (6%) among South East region residents compared to those from Central Highlands and for those who lived further away from the hospital. The visit numbers were significantly higher among older age groups (5-11%), those with health insurance (6%), and those with comorbidities (5%) compared to others. Although the number of hospital visits by females was higher (7%) than males in 2017, it significantly decreased in subsequent years. CONCLUSIONS: Our study indicated that there are both structural and individual factors affecting the number of visits for HCV treatment. To meet the global strategy for elimination of HCV, Vietnam Government needs to address the structural and personal barriers to healthcare seeking, with a special focus on women.


Subject(s)
Hepatitis C, Chronic , Hepatitis C , Male , Humans , Female , Aged , Hepatitis C, Chronic/drug therapy , Hepatitis C, Chronic/epidemiology , Vietnam/epidemiology , Hepacivirus , Patient Acceptance of Health Care
9.
Gels ; 9(11)2023 Nov 09.
Article in English | MEDLINE | ID: mdl-37998978

ABSTRACT

This manuscript explores the interaction between methylene blue dye and gelatin within a membrane using spectroscopy and image analysis. Emphasis is placed on methylene blue's unique properties, specifically its ability to oscillate between two distinct resonance states, each with unique light absorption characteristics. Image analysis serves as a tool for examining dye diffusion and absorption. The results indicate a correlation between dye concentrations and membrane thickness. Thinner layers exhibit a consistent dye concentration, implying an even distribution of the dye during the diffusion process. However, thicker layers display varying concentrations at different edges, suggesting the establishment of a diffusion gradient. Moreover, the authors observe an increased concentration of gelatin at the peripheries rather than at the center, possibly due to the swelling of the dried sample and a potential water concentration gradient. The manuscript concludes by suggesting image analysis as a practical alternative to spectral analysis, particularly for detecting whether methylene blue has been adsorbed onto the macromolecular network. These findings significantly enhance the understanding of the complex interactions between methylene blue and gelatin in a membrane and lay a solid foundation for future research in this field.

10.
Med Mycol ; 61(10)2023 Oct 05.
Article in English | MEDLINE | ID: mdl-37771088

ABSTRACT

Host non-T cell markers to aid in the diagnosis of cryptococcal meningoencephalitis (CM) have not been identified. In this case-control study, we characterized antibody and B cell profiles in HIV-negative and HIV-positive Vietnamese individuals of the Kinh ethnicity recently diagnosed with CM and controls. The study included 60 HIV-negative with no known immunocompromising condition and 60 HIV-positive individuals, with 30 CM cases and 30 controls in each group. Participants were matched by age, sex, HIV serostatus, and CD4 count in the HIV-positive group. Plasma immunoglobulin (Ig) levels, including IgG1, IgG2, IgM, and IgA, Cryptococcus spp. glucuronoxylomannan (GXM)- and laminarin (branched ${\rm{\beta }}$-[1-3]-glucan)-binding IgG, IgM, IgA levels, and peripheral blood B cell subsets were measured. Logistic regression, principal component, and mediation analyses were conducted to assess associations between antibody, B cell levels, and CM. The results showed that GXM-IgG levels were higher and IgG1 and IgG2 were lower in CM cases than controls, regardless of HIV status. In HIV-negative individuals, IgG2 mediated an inverse association between CD19+CD27+CD43+CD5- (B-1b-like) cells and CM. In HIV-positive individuals, lower levels of IgA, laminarin-IgA, and CD19+CD27+IgM+IgD- (IgM+ memory B) cells were each associated with CM. The shared and distinct antibody and B cell profiles identified in HIV-negative and HIV-positive CM cases may inform the identification of non-T-cell markers of CM risk or unsuspected disease, particularly in HIV-negative individuals.


Unlike cryptococcal meningitis (CM) in HIV-positive individuals, there are no known biomarkers of risk in HIV-negative individuals and the diagnosis is often not suspected and delayed. This study identified non-T cells, including antibody and B cell CM-associated profiles that may guide cryptococcal antigen testing in HIV-negative individuals.


Subject(s)
Cryptococcus neoformans , HIV Infections , Meningitis, Cryptococcal , Meningoencephalitis , Humans , Case-Control Studies , HIV Infections/complications , HIV Infections/veterinary , Immunoglobulin M , Immunoglobulin G , Meningoencephalitis/veterinary , Immunoglobulin A , Meningitis, Cryptococcal/veterinary
11.
Materials (Basel) ; 16(14)2023 Jul 16.
Article in English | MEDLINE | ID: mdl-37512301

ABSTRACT

A superior heterojunction of HC-ZnBi-LDO was synthesized in two steps, namely hydrothermal carbonization, followed by co-precipitation. The 2% HC-ZnBi-LDO heterojunction photocatalysts could degrade over 90.8% of 30 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D) using 1.0 g/L of the catalyst after 135 min of visible light exposure at pH 4. The activity of 2% HC-ZnO-LDO was remarkably stable. Approximately 86.4-90.8% of 30 mg/L 2,4-D was degraded, and more than 79-86.4% of TOC was mineralized by 2% HC-ZnBi-LDO at pH 4 after 135 min of visible light exposure during four consecutive cycles. The rapid separation and migration of charge carriers at the interfaces between HC and ZnBi-LDO were achieved within 2% HC-ZnBi-LDO. Moreover, the electron acceptor characteristic of HC in 2% HC-ZnBi-LDO caused the recombination of charge carriers to decrease significantly, thus generating more reactive radicals, such as hydroxyl radicals (OH●) and superoxide radicals (O2●-). These results demonstrate that the novel 2% HC-ZnBi-LDO is a superior photocatalyst for the remediation of hazardous organic pollutants.

12.
Clin Liver Dis (Hoboken) ; 21(5): 138-142, 2023 May.
Article in English | MEDLINE | ID: mdl-37274950

ABSTRACT

Nucleic acid testing to confirm sustained virological response (SVR) after HCV therapy is technical, often expensive, and frequently unavailable where disease prevalence is highest. Alternative surrogate biomarkers merit evaluation. In a short-treatment trial in Vietnam (SEARCH-1; n = 52) we analysed how changes in alanine transaminase (ΔALT) and aspartate transaminase (ΔAST), from end of treatment (EOT) to EOT + 12 weeks, related to SVR, defined as HCV RNA < lower limit of quantification 12 weeks after EOT. In a separate UK trial (STOPHCV1; n = 202), we then tested the hypothesis that any elevation in ALT or AST between EOT and EOT12 is a sensitive screen for treatment failure. In SEARCH-1, among 48 individuals with data, 13 failed to achieve SVR. Median ΔALT and ΔAST were negative in cured patients but elevated when treatment failed [median ΔALT (IQR): -2 IU/L (-6, +2)] versus +17 IU/L (+7.5, +38) (p< 0.001). Amongst treatment failures, 12/13 had increase in ALT and 13/13 had increase in AST after EOT, compared with 12/35 in those cured. In STOPHCV1, 196/202 patients had evaluable data, of which 57 did not achieve SVR. A rise in ALT after EOT was 100% sensitive (95% C.I. [93.7 - 100%]) and 51% specific (42.4 - 59.7%) for detecting treatment failure. ΔAST >0 IU/L was 98.1% (89.9 - 99.9%) sensitive and 35.8% (27.3 - 45.1%) specific. A rise in ALT or AST after HCV therapy is a highly sensitive screen for treatment failure in mild liver disease. This finding could reduce costs and complexity of managing HCV.

13.
Emerg Infect Dis ; 29(5): 1002-1006, 2023 05.
Article in English | MEDLINE | ID: mdl-37015283

ABSTRACT

We analyzed 1,303 SARS-CoV-2 whole-genome sequences from Vietnam, and found the Alpha and Delta variants were responsible for a large nationwide outbreak of COVID-19 in 2021. The Delta variant was confined to the AY.57 lineage and caused >1.7 million infections and >32,000 deaths. Viral transmission was strongly affected by nonpharmaceutical interventions.


Subject(s)
COVID-19 , Humans , COVID-19/epidemiology , SARS-CoV-2/genetics , Vietnam/epidemiology , Disease Outbreaks
14.
RSC Adv ; 13(14): 9732-9748, 2023 Mar 20.
Article in English | MEDLINE | ID: mdl-37008403

ABSTRACT

In this work, we study the charge transfer improvement by the combination of two semiconductors of SERS. The energy levels of the semiconductor, when combined, become intermediate energy levels that support the charge transfer from the HOMO to the LUMO level, amplifying the Raman signal of the organic molecules. The SERS substrates of Ag/a-Al2O3-Al/ZnO nanorods with high sensitivity are prepared for detecting dye rhodamine 6G (R6G) and metronidazole (MNZ) standard. The highly ordered vertically grown ZnO nanorods (NRs) are first developed on a glass substrate by a wet chemical bath deposition method. Then, ZnO NRs are covered with an amorphous oxidized aluminum thin film by a vacuum thermal evaporation method to produce a platform with a large surface area and high charge transfer performance. Finally, silver nanoparticles (NPs) are decorated onto this platform to form an active SERS substrate. The structure, surface morphology, optical properties, and elements in the sample are investigated by Raman spectroscopy, X-ray diffractometry, field-emission scanning electron microscopy (FE-SEM), ultraviolet-visible spectroscopy (UV-vis), reflectance spectroscopy, and energy dispersion X-ray spectroscopy (EDS). Rhodamine 6G is used as a reagent to evaluate the SERS substrates with an analytical enhancement factor (EF) of ∼1.85 × 1010 at the limit of detection (LOD) of 10-11 M. These SERS substrates are used to detect metronidazole standard at a LOD of 0.01 ppm and an EF of 2.2 × 106. The SERS substrate exhibits high sensitivity and stability for promising wide application in chemical, biomedical, and pharmaceutical detection.

15.
Pathogens ; 12(4)2023 Apr 21.
Article in English | MEDLINE | ID: mdl-37111514

ABSTRACT

African swine fever (ASF) is a highly contagious swine disease with high mortality. In many countries, culling pigs infected and exposed to the ASF virus is mandatory to control the disease, which poses a real challenge in the disposal of large numbers of carcasses during ASF outbreaks. Shallow burial with carbon (SBC) Thanks ew mortality disposal method developed from deep burial and composting. The present study investigates the effectiveness of SBC in disposing of ASF virus-infected pigs. The real-time PCR results showed that DNA of the ASF virus was still detected in bone marrow samples on day 56, while the virus isolation test revealed that the infectious ASF virus was destroyed in both spleen and bone marrow samples on day 5. Interestingly, decomposition was found to occur rapidly in these shallow burial pits. On day 144, only large bones were found in the burial pit. In general, the results of this study indicated that SBC is a potential method for the disposal of ASF-infected carcasses; however, further studies are needed to provide more scientific evidence for the efficacy of SBC in different environment conditions.

16.
Hosp Pract (1995) ; 51(3): 141-148, 2023 Aug.
Article in English | MEDLINE | ID: mdl-36974626

ABSTRACT

BACKGROUND: This study was designed to assess the impact of postoperative atrial fibrillation (POAF) on short- and long-term outcomes after cardiac surgery. METHODS: We prospectively assessed POAF concerning outcomes in 379 adult patients who had undergone cardiac surgery in two heart surgery centers with a follow-up period of one year for every patient. The effects of POAF on postoperative events were evaluated using Logistic regression, Cox regression (adjusted for propensity score), and Kaplan-Meier analysis. RESULTS: The incidence of POAF was 27.2%. Multivariable logistic regression analysis revealed POAF was associated with an increased risk of 6-month (OR = 5.36; CI: 1.51-18.94; p = 0.009), and 1-year mortality (OR = 4.56; CI: 1.29-16.04; p = 0.018) as well as Major Adverse Cardiocerebral Events (MACEs; acute MI, cardiac arrest, low cardiac output after surgery, third-degree atrioventricular block or stroke; OR = 3.02; CI: 1.29-7.05; p = 0.011), Intensive Care Unit (ICU) stay > 3 days (OR = 2.39; CI: 1.14-5.00; p = 0.021), and postoperative stay > 14 days (OR = 3.12; CI: 1.65-5.90; p < 0.001). Multivariable Cox regression analysis showed POAF as an independent predictor of mortality at one year (HR = 2.86; CI: 1.05-7.75; p = 0.038). Discharge plans including statin and beta-blocker had an independent association with a reduced mortality at one year (HR = 0.22; CI: 0.05-0.96; p = 0.045; HR = 0.16; CI: 0.03-0.87; p = 0.034, respectively). CONCLUSIONS: POAF is associated with an increased risk of morbidity, all-cause mortality, and hospital duration. Statins and beta-blockers that were included in discharge plans had an independent association with reduction in 1-year all-cause mortality.


Subject(s)
Atrial Fibrillation , Cardiac Surgical Procedures , Adult , Humans , Atrial Fibrillation/epidemiology , Atrial Fibrillation/etiology , Vietnam/epidemiology , Prospective Studies , Cardiac Surgical Procedures/adverse effects , Kaplan-Meier Estimate , Postoperative Complications/epidemiology , Risk Factors
17.
Chem Biodivers ; 20(3): e202200210, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36732885

ABSTRACT

There is an ongoing interest to identify alternative pesticidal agents to avoid the chronic problems associated with synthetic pesticides. Essential oils have shown promise as botanical pest control agents. In the present study, the essential oils of four members of the Lamiaceae (Callicarpa candicans, C. erioclona, C. macrophylla, and Karomia fragrans; Vietnamese names: Nàng nàng, Tu châu lông mem, Tu châu lá to and Cà dien, respectively), obtained from wild populations in Vietnam, have been obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry. The essential oils were formulated into microemulsions and the essential oils and their microemulsions were screened for mosquito larvicidal activity against Aedes aegypti, Aedes albopictus, Culex quinquefasciatus, and for molluscicidal activity against Pomacea canaliculata. Atractylone and (E)-caryophyllene dominated the volatiles of C. candicans (CCEO) and C. erioclona (CEEO), while the major component in C. macrophylla (CMEO) and K. fragrans (KFEO) was (E)-caryophyllene. The essential oils and microemulsions of both C. candicans and C. erioclona exhibited excellent larvicidal activity against all three mosquito species (Ae. aegypti, Ae. albopictus, and Cx. quinquefasciatus) with LC50 values <10 µg/mL. Additionally, the larvicidal activity of the microemulsions were significantly improved compared with their free essential oils, especially for C. candicans and C. erioclona. All four essential oils and their microemulsions showed excellent molluscicidal activity with LC50 <10 µg/mL. In most cases, the essential oils and microemulsions showed greater pesticidal activity against target organisms than the non-target freshwater fish, Oreochromis niloticus. The in silico studies on physicochemical and ADMET properties of the major components in the studied essential oils were also investigated and most of the compounds possessed a favorable ADMET profile. Computational modeling studies of the studied compounds demonstrated a favorable binding interaction with the mosquito odorant-binding protein target and support atractylone, ß-selinene, and caryophyllene oxide as potential inhibitors. Based on the observed pesticidal activities of the essential oils and their microemulsions, the Callicarpa species and K. fragrans should be considered for potential cultivation and further exploration as botanical pesticidal agents.


Subject(s)
Aedes , Callicarpa , Insecticides , Lamiaceae , Oils, Volatile , Pesticides , Animals , Oils, Volatile/pharmacology , Oils, Volatile/chemistry , Pesticides/pharmacology , Vietnam , Insecticides/pharmacology , Insecticides/chemistry , Larva
18.
Anal Chim Acta ; 1240: 340741, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36641155

ABSTRACT

Supercritical Fluid Chromatography (SFC), a high-throughput separation technique, has been widely applied as a promising routine method in pharmaceutical, pesticides, and metabolome analysis in the same way as conventional liquid chromatography and gas chromatography. Unified chromatography (UC), an advanced version of SFC, which applied gradient elution with mobile phase changing continuously from supercritical to subcritical and to liquid states, can further extend the SFC applications. UC mostly applying the popular mobile phase of 95%:5%/Methanol:Water with additives allows to analyze many hydrophilic compounds. However, many of phosphorylated metabolites or multi carboxylic acids show very poor peak shapes or even can't be eluted under UC conditions, thus hampering the UC's metabolome coverage. In this study, we proposed the first proof-of-concept of UC/HILIC, a novel strategy to extend the current UC metabolome coverage by employing an aqueous gradient right after the UC gradient on a single packed column in a single measurement. The proposed method showed significant improvement regarding the chromatographic performance and metabolome coverage, while still maintaining the precision and high throughput in comparison with conventional UC methods.


Subject(s)
Chromatography, Supercritical Fluid , Methanol , Methanol/chemistry , Chromatography, Liquid , Chromatography, Supercritical Fluid/methods , Water/chemistry , Metabolome
19.
Elife ; 122023 Jan 09.
Article in English | MEDLINE | ID: mdl-36622106

ABSTRACT

Background: World Health Organization has called for research into predictive factors for selecting persons who could be successfully treated with shorter durations of direct-acting antiviral (DAA) therapy for hepatitis C. We evaluated early virological response as a means of shortening treatment and explored host, viral and pharmacokinetic contributors to treatment outcome. Methods: Duration of sofosbuvir and daclatasvir (SOF/DCV) was determined according to day 2 (D2) virologic response for HCV genotype (gt) 1- or 6-infected adults in Vietnam with mild liver disease. Participants received 4- or 8-week treatment according to whether D2 HCV RNA was above or below 500 IU/ml (standard duration is 12 weeks). Primary endpoint was sustained virological response (SVR12). Those failing therapy were retreated with 12 weeks SOF/DCV. Host IFNL4 genotype and viral sequencing was performed at baseline, with repeat viral sequencing if virological rebound was observed. Levels of SOF, its inactive metabolite GS-331007 and DCV were measured on days 0 and 28. Results: Of 52 adults enrolled, 34 received 4 weeks SOF/DCV, 17 got 8 weeks and 1 withdrew. SVR12 was achieved in 21/34 (62%) treated for 4 weeks, and 17/17 (100%) treated for 8 weeks. Overall, 38/51 (75%) were cured with first-line treatment (mean duration 37 days). Despite a high prevalence of putative NS5A-inhibitor resistance-associated substitutions (RASs), all first-line treatment failures cured after retreatment (13/13). We found no evidence treatment failure was associated with host IFNL4 genotype, viral subtype, baseline RAS, SOF or DCV levels. Conclusions: Shortened SOF/DCV therapy, with retreatment if needed, reduces DAA use in patients with mild liver disease, while maintaining high cure rates. D2 virologic response alone does not adequately predict SVR12 with 4-week treatment. Funding: Funded by the Medical Research Council (Grant MR/P025064/1) and The Global Challenges Research 70 Fund (Wellcome Trust Grant 206/296/Z/17/Z).


Hepatitis C is a blood-borne virus that causes thousands of deaths from liver cirrhosis and liver cancer each year. Antiviral therapies can cure most cases of infection in 12 weeks. Unfortunately, treatment is expensive, and sticking with the regimen for 12 weeks can be difficult. It may be especially challenging for unhoused people or those who use injection drugs and who have high rates of hepatitis C infection. Shorter durations of therapy may make it more accessible, especially for high-risk populations. But studies of shorter antiviral treatment durations have yet to produce high enough cure rates. Finding ways to identify patients who would benefit from shorter therapy is a key goal of the World Health Organization. Potential characteristics that may predict a faster treatment response include low virus levels before initiating treatment, patient genetics, drug resistance mutations in the virus, and higher drug levels in the patient's blood during treatment. For example, previous research showed that a rapid decrease in virus levels in a patient's blood two days after starting antiviral therapy with three drugs predicted patient cures after three weeks of treatment. To test if high cure rates could be achieved in just four weeks of treatment, Flower et al. enrolled 52 patients with hepatitis C in a study to receive the most widely accessible dual antiviral treatment (sofosbuvir and daclatasvir). Participants received four or eight weeks of treatment, depending on the amount of viral RNA in their blood after two days of treatment. The results indicate that a rapid decrease in virus levels in the blood does not adequately predict cure rates with four weeks of two-drug combination therapy. However, eight weeks may be highly effective, regardless of viral levels early in treatment. Thirty-four individuals with low virus levels on the second day of treatment received four weeks of therapy, which cured 21 or 62% of them. All seventeen individuals with higher viral levels on day two were cured after eight weeks of treatment. Twelve weeks of retreatment was sufficient to cure the 13 individuals who did not achieve cure with four weeks of therapy. Even patients with drug resistance genes after the first round of therapy responded to a longer second round. Flower et al. show that patient genetics, virus subtype, drug levels in the patient's blood, and viral drug resistance genes before therapy, were not associated with patient cures after four weeks of treatment. Given that retreatment is safe and effective, larger studies are now needed to determine whether eight weeks of therapy with sofosbuvir and daclatasvir may be enough to cure patients with mild liver disease. More studies are also necessary to identify patients that may benefit from shorter therapy durations. Finding ways to shorten antiviral therapy for hepatitis C could help make treatment more accessible and reduce therapy costs for both individuals and governments.


Subject(s)
Hepatitis C, Chronic , Hepatitis C , Adult , Humans , Sofosbuvir/therapeutic use , Antiviral Agents , Pilot Projects , Hepatitis C, Chronic/drug therapy , Drug Therapy, Combination , Treatment Outcome , Hepacivirus/genetics , Genotype , Ribavirin/therapeutic use , Interleukins/genetics
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