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1.
Public Health Action ; 14(1): 7-13, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38798783

ABSTRACT

It is essential that communities at risk from TB are involved in TB research. Community advisory groups (CAGs) are one mechanism for involving communities in research and creating platforms for discussions between researchers and community members. We organised a CAG meeting with community members and people with lived experience in Ho Chi Minh City, Vietnam, to explore the community's knowledge about TB and their perspectives on different diagnostic tests in Vietnam, a low-middle-income country with a high TB burden. Researchers shared basic information and addressed questions about TB. CAG members commented on preference of TB screening tests, and suggested that chest X-rays and blood tests were more acceptable than sputum tests because of the difficulty in sputum expectoration. In addition, clinical studies that required fewer visits to the hospitals would be preferred, even if this meant a greater reliance on blood sampling.


Il est essentiel que les communautés exposées au risque de TB soient impliquées dans la recherche sur la TB. Les groupes consultatifs communautaires (CAG, pour l'anglais « community advisory groups ¼) constituent un mécanisme permettant d'impliquer les communautés dans la recherche et de créer des plateformes de discussion entre les chercheurs et les membres de la communauté. Nous avons organisé une réunion du CAG avec des membres de la communauté et des personnes ayant une expérience vécue à Ho Chi Minh Ville, au Viêt Nam, afin d'explorer les connaissances de la communauté sur la TB et leurs perspectives sur les différents tests de diagnostic au Viêt Nam, un pays à revenu faible et moyen où la charge de la TB est élevée. Les chercheurs ont partagé des informations de base et répondu à des questions sur la TB. Les membres du CAG ont fait part de leur préférence pour les tests de dépistage de la TB et ont suggéré que les radiographies pulmonaires et les analyses de sang étaient plus acceptables que les tests d'expectoration en raison de la difficulté d'expectoration des crachats. En outre, les études cliniques qui nécessitent moins de visites dans les hôpitaux seraient préférées, même si cela implique une plus grande dépendance à l'égard des prélèvements sanguins.

2.
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.

3.
Indian J Microbiol ; 63(3): 386-394, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37781021

ABSTRACT

Tomato (Solanum lycopersicum L.) is an important grown vegetable in Vietnam. Bacterial wilt caused by Pseudomonas solanacearum has been considered to be an important disease resulting in a harvest loss up to 90% and significant economic loss to farmers. In this study, two bacteriophages DLDT_So2 and BHDT_So9 specific to P. solanacearum were isolated. Morphological analysis indicated that DLDT_So2 and BHDT_So9 had podovirus morphology and were classified into Autographiviridae family. The latent period and burst size of DLDT_So2 was found to be approximately 120 min and 20.0 ± 2.4 virions per infected cell. Meanwhile, the latent period of BHDT_So9 was 140 min with a burst size of 11.5 ± 2.8 virions per infected cell. Of the 23 bacterial strains tested, the phages infected 7/11 strains of P. solanacearum and none of the other bacteria tested were susceptible to the phages. Stability of the phages at different temperatures, pHs, solvents was also investigated. The genomes of DLDT_So2 and BHDT_So9 are 41,341 bp and 41,296 bp and long with a total GC content of 63%, contains 48 and 46 predicted protein-encoding CDSs. No virulence or antibiotic resistance genes were found in the genomes, suggesting they would be useful biocontrol agents against P. solanacearum. Classification of the phage using average nucleotide identity, phylogenetic analysis was also carried out. The two phages represented new species when they had overall average nucleotide identity of < 95%. This is first report of the isolation and characterization of P. solanacearum-specific phages from tomato farms in Vietnam. Supplementary Information: The online version contains supplementary material available at 10.1007/s12088-023-01090-9.

4.
Chemosphere ; 345: 140464, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37852378

ABSTRACT

The objective of the present study is to synthesize g-C3N4-Ni nanocomposites composed of graphitic carbon nitride and magnetic nickel nanoparticles for benzopyrene degradation, which is one of the most potent polycyclic aromatic hydrocarbons (PAH) molecules. The concocted g-C3N4-Ni nanocomposites contained confined nanospheres with a mean particle dimension of 22 nm. Batch adsorption studies revealed that a rise in adsorbent dosage elevates benzopyrene degradation percentage in both water and soil samples with respect to time. The increase in the benzopyrene concentration did not have much influence on the degradation efficiency, and hence, the minimal concentration of PAH molecule is essential for the effective adsorption by g-C3N4-Ni nanocomposites. The rise in pH tends to increase the degradation of Benzopyrene till 3 h of the incubation period, and beyond 3 h, the degradation percentage declines. With regard to the effect of light source, UV light has been shown to accelerate the degradation of benzopyrene by g-C3N4-Ni nanocomposites than sunlight. The adsorption kinetic and isotherm investigations have proven that the Pseudo-second order kinetic model and Freundlich isotherm model were appropriate for our study. Thus, the g-C3N4-Ni nanocomposites were found to be efficient as a photocatalyst for the adsorption of benzopyrene from environmental samples.


Subject(s)
Nanocomposites , Polycyclic Aromatic Hydrocarbons , Nickel/chemistry , Nanocomposites/chemistry , Water/chemistry , Benzopyrenes , Catalysis
5.
Ann Ig ; 35(6): 641-659, 2023.
Article in English | MEDLINE | ID: mdl-37313797

ABSTRACT

Background: In Vietnam, cervical cancer is a significant public health concern for women. Unfortunately, despite the availability of the HPV vaccine, low vaccination rates persist. Objectives: This study investigates the discrepancy between urban and rural areas in the willingness to receive HPV vaccination with or without fees. Methods: A cross-sectional study was conducted on a sample of 648 women aged between 15 and 49, living in two urban and two rural Vietnamese districts of Can Tho, between May and December 2021. Results: The overall vaccination rate was 4%, with urban women having a higher rate of 4.9% compared to rural women at 3.1%. Among unvaccinated women, those from rural areas expressed a significantly higher desire to receive the free vaccine (91.4%) than urban women (84.4%). However, the intention to vaccinate declined when rural women and urban women were advised to pay the cost (63.4% and 57.1%, respectively). A strong correlation was found between a positive attitude and intention for vaccination, irrespective of its price or free availability. Education and access to information about the HPV vaccine were also identified as the most significant factors influencing the intention to vaccination among urban and rural women. Conclusion: The low HPV vaccination rates among women aged 15-49 living in both urban and rural regions of Vietnam are a notable public health concern. These outcomes emphasize the critical need for effective programs of vaccine laterization, as an introduction to the offer of affordable and accessible HPV vaccines for women in Can Tho, Vietnam.


Subject(s)
Papillomavirus Infections , Papillomavirus Vaccines , Uterine Cervical Neoplasms , Humans , Female , Adolescent , Young Adult , Adult , Middle Aged , Papillomavirus Infections/prevention & control , Human Papillomavirus Viruses , Vietnam , Cross-Sectional Studies , Vaccination , Uterine Cervical Neoplasms/prevention & control , Health Knowledge, Attitudes, Practice , Patient Acceptance of Health Care
6.
Parasite ; 30: 23, 2023.
Article in English | MEDLINE | ID: mdl-37350678

ABSTRACT

Although interest in Acanthocephala seems to have reached only a small community of researchers worldwide, we show in this opinion article that this group of parasites is composed of excellent model organisms for studying key questions in parasite molecular biology and cytogenetics, evolutionary ecology, and ecotoxicology. Their shared ancestry with free-living rotifers makes them an ideal group to explore the origins of the parasitic lifestyle and evolutionary drivers of host shifts and environmental transitions. They also provide useful features in the quest to decipher the proximate mechanisms of parasite-induced phenotypic alterations and better understand the evolution of behavioral manipulation. From an applied perspective, acanthocephalans' ability to accumulate contaminants offers useful opportunities to monitor the impacts - and evaluate the possible mitigation - of anthropogenic pollutants on aquatic fauna and develop the environmental parasitology framework. However, exploring these exciting research avenues will require connecting fragmentary knowledge by enlarging the taxonomic coverage of molecular and phenotypic data. In this opinion paper, we highlight the needs and opportunities of research on Acanthocephala in three main directions: (i) integrative taxonomy (including non-molecular tools) and phylogeny-based comparative analysis; (ii) ecology and evolution of life cycles, transmission strategies and host ranges; and (iii) environmental issues related to global changes, including ecotoxicology. In each section, the most promising ideas and developments are presented based on selected case studies, with the goal that the present and future generations of parasitologists further explore and increase knowledge of Acanthocephala.


Title: Accrocher la communauté scientifique à des vers à la tête pleine d'épines : faits intéressants et passionnants, lacunes dans les connaissances et perspectives pour des orientations de recherche sur les Acanthocéphales. Abstract: Bien que l'intérêt pour les acanthocéphales semble n'avoir atteint qu'un petit nombre de chercheurs dans le monde, nous montrons dans cet article que ce groupe de parasites est composé d'excellents organismes modèles pour étudier les questions en suspens en biologie moléculaire et cytogénétique, écologie évolutive et écotoxicologie. Leur ascendance partagée avec les rotifères en fait un groupe idéal pour explorer les origines du mode de vie parasitaire et les moteurs évolutifs des changements d'hôtes et des transitions environnementales. Ils présentent également des caractéristiques intéressantes pour l'étude des mécanismes proximaux sous-tendant les altérations phénotypiques induites par les parasites, et ainsi mieux comprendre l'évolution de la manipulation comportementale. D'un point de vue appliqué, la capacité des acanthocéphales à accumuler les contaminants offre des opportunités utiles pour surveiller les impacts - et évaluer les possibilités d'atténuation - des pollutions anthropiques sur la faune aquatique et développer le domaine de la parasitologie environnementale. Cependant, l'exploration de ces pistes de recherche passionnantes nécessitera de relier des connaissances fragmentaires en élargissant la couverture taxonomique des données moléculaires et phénotypiques. Dans cet article, nous présentons l'état actuel de la recherche sur les acanthocéphales selon trois axes principaux : (i) la taxonomie intégrative (y compris les outils non-moléculaires) et la phylogénie à des fins d'analyse comparative ; (ii) l'écologie et l'évolution des cycles de vie, des stratégies d'exploitation des hôtes et de transmission ; (iii) les questions environnementales liées aux changements globaux, y compris l'écotoxicologie. Dans chaque section, nous soulignons les besoins et les opportunités, en espérant que cela incitera une nouvelle génération de parasitologues à s'intéresser aux acanthocéphales.


Subject(s)
Acanthocephala , Parasites , Rotifera , Animals , Acanthocephala/genetics , Phylogeny
7.
Arch Virol ; 168(6): 157, 2023 May 09.
Article in English | MEDLINE | ID: mdl-37160612

ABSTRACT

Bacteriophage L522, which infects Xanthomonas oryzae pv. oryzae, was isolated from a paddy leaf sample collected in Long An province, Vietnam. The phage shows myovirus morphology based on transmission electron microscopy. It displays a latent period and burst size of approximately 3 h and 63 new virions per infected cell (PFU/infected cell), respectively. The genome of L522 is 44,497 bp in length, with 52% GC content. Of the 63 genes identified, functions were predicted for 26. No virulence or antibiotic-resistance genes were detected. The results of a BLASTn search showed similarity to a previously reported Xanthomonas phage, with 85% average nucleotide sequence identity and 87.15% query coverage. Thus, this L522 is a representative of a new species in the genus Xipdecavirus.


Subject(s)
Bacteriophages , Oryza , Siphoviridae , Xanthomonas , Bacteriophages/genetics , Xanthomonas/genetics
8.
Liver Int ; 43(6): 1195-1203, 2023 06.
Article in English | MEDLINE | ID: mdl-36825358

ABSTRACT

BACKGROUND: Global data on the treatment rate with direct-acting antivirals (DAAs) for chronic hepatitis C (CHC) are sparse. We aimed to evaluate the CHC treatment rate and barriers to treatment in the DAA era. METHODS: We searched PubMed, EMBASE and Cochrane from inception to 5 August 2021, for relevant articles. Patients treated with DAAs without interferon (IFN) therapy were categorized as IFN-free DAAs. Patients receiving DAA with IFN or unclear IFN status were categorized as DAA/IFN. RESULTS: We identified and analysed data from 146 studies (1 760 352 CHC patients). DAA/IFN treatment rate was 16.0% (95% CI: 9.9-23.3, 49 studies, 886 535 patients). IFN-free DAA treatment rate was 52.3% (95% CI: 46.2-58.4, 123 studies, 1 276 754 patients): 45.4% in North America, 64.2% in South America (1 study), 90.4% in Africa (most data from Egypt), 54.4% in Europe, 60.7% in Australia and 60.5% in Asia, (p < .0001); 49% with hepatitis B co-infection and 32.3% with hepatocellular carcinoma (HCC). Treatment was not a priority in 22.8% of patients in Europe and 16.7% in Australia, compared to only 4.8% in North America and 2.1% in Asia (p < .0001). Poor adherence to clinical follow-up was the cause of no treatment in 74.7% of patients in Australia, 37.0% in North America, 7.9% in Europe and 14.3% in Asia (p < .0001). CONCLUSION: Though a marked improvement from IFN/DAA, the treatment rate with IFN-free DAA remains suboptimal (52.3% overall, 32.3% in HCC patients). Non-adherence to clinical follow-up and lack of disease awareness were treatment barriers.


Subject(s)
Carcinoma, Hepatocellular , Hepatitis C, Chronic , Hepatitis C , Liver Neoplasms , Humans , Antiviral Agents/therapeutic use , Hepacivirus/genetics , Hepatitis C, Chronic/complications , Hepatitis C/drug therapy
9.
Sci Total Environ ; 872: 162196, 2023 May 10.
Article in English | MEDLINE | ID: mdl-36781140

ABSTRACT

Our capacity to predict trajectories of ecosystem degradation and recovery is limited, especially when impairments are caused by multiple stressors. Recovery may be fast or slow and either complete or partial, sometimes result in novel ecosystem states or even fail completely. Here, we introduce the Asymmetric Response Concept (ARC) that provides a basis for exploring and predicting the pace and magnitude of ecological responses to, and release from, multiple stressors. The ARC holds that three key mechanisms govern population, community and ecosystem trajectories. Stress tolerance is the main mechanism determining responses to increasing stressor intensity, whereas dispersal and biotic interactions predominantly govern responses to the release from stressors. The shifting importance of these mechanisms creates asymmetries between the ecological trajectories that follow increasing and decreasing stressor intensities. This recognition helps to understand multiple stressor impacts and to predict which measures will restore communities that are resistant to restoration.


Subject(s)
Ecosystem , Rivers
10.
Philos Trans R Soc Lond B Biol Sci ; 378(1867): 20210081, 2023 01 02.
Article in English | MEDLINE | ID: mdl-36373926

ABSTRACT

Many natural forests in Southeast Asia are degraded following decades of logging. Restoration of these forests is delayed by ongoing logging and tropical cyclones, but the implications for recovery are largely uncertain. We analysed meteorological, satellite and forest inventory plot data to assess the effect of Typhoon Doksuri, a major tropical cyclone, on the forest landscapes of central Vietnam consisting of natural forests and plantations. We estimated the return period for a cyclone of this intensity to be 40 years. Plantations were almost twice as likely to suffer cyclone damage compared to natural forests. Logged natural forests (9-12 years after cessation of government-licensed logging) were surveyed before and after the storm with 2 years between measurements and remained a small biomass carbon sink (0.1 ± 0.3 Mg C ha-1 yr-1) over this period. The cyclone reduced the carbon sink of recovering natural forests by an average of 0.85 Mg C ha-1 yr-1, less than the carbon loss due to ongoing unlicensed logging. Restoration of forest landscapes in Southeast Asia requires a reduction in unlicensed logging and prevention of further conversion of degraded natural forests to plantations, particularly in landscapes prone to tropical cyclones where natural forests provide a resilient carbon sink. This article is part of the theme issue 'Understanding forest landscape restoration: reinforcing scientific foundations for the UN Decade on Ecosystem Restoration'.


Subject(s)
Cyclonic Storms , Forestry , Ecosystem , Vietnam , Forests , Tropical Climate , Trees , Conservation of Natural Resources
11.
Sci Rep ; 12(1): 21355, 2022 12 09.
Article in English | MEDLINE | ID: mdl-36494427

ABSTRACT

We compared seven node vaccination strategies in twelve real-world complex networks. The node vaccination strategies are modeled as node removal on networks. We performed node vaccination strategies both removing nodes according to the initial network structure, i.e., non-adaptive approach, and performing partial node rank recalculation after node removal, i.e., semi-adaptive approach. To quantify the efficacy of each vaccination strategy, we used three epidemic spread indicators: the size of the largest connected component, the total number of infected at the end of the epidemic, and the maximum number of simultaneously infected individuals. We show that the best vaccination strategies in the non-adaptive and semi-adaptive approaches are different and that the best strategy also depends on the number of available vaccines. Furthermore, a partial recalculation of the node centrality increases the efficacy of the vaccination strategies by up to 80%.


Subject(s)
Epidemics , Humans , Epidemics/prevention & control , Vaccination
12.
Aquat Toxicol ; 247: 106178, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35489172

ABSTRACT

Physiologically based pharmacokinetic (PBPK) models have been applied to simulate the absorption, distribution, metabolism, and elimination of various toxicants in fish. This approach allows for considering metal accumulation in intestinal parasites. Unlike "semi" physiologically-based models developed for metals, metal accumulation in fish was characterised based on metal-specific parameters (the fraction in blood plasma and the tissue-blood partition coefficient) and physiological characteristics of the fish (the blood flow and the tissue weight) in our PBPK model. In the model, intestinal parasites were considered a sink of metals from the host intestine. The model was calibrated with data for the system of the chub Squalius cephalus and the acanthocephalan Pomphorhynchus tereticolliis. Metal concentrations in this fish-parasite system were monitored in Ag and Co treatments in duplicate during a 48-day exposure phase (Ag and Co were added to tap water at concentrations of 1 and 2 µg/L, respectively) and a 51-day depuration phase. Their concentrations in the gills increased during the exposure phase and decreased in the depuration phase. A similar pattern was observed for Ag concentrations in other chub organs, while a relatively stable pattern for Co indicates regulations in the accumulation of essential metals by chubs. The metals were taken up by the acanthocephalans at similar rate constants. These results indicate that metal availability to parasites, which is determined by the internal distribution and fate, is critical to metal accumulation in the acanthocephalans. The high concentration of Ag in the liver as well as the high rate of Ag excretion from the liver to the intestine might contribute to higher concentrations of metals in the bile complexes in the intestine, which are available to the parasites, but not to the reabsorption by the host intestine. The opposite pattern might explain the lower availability of Co to the acanthocephalans.


Subject(s)
Acanthocephala , Cyprinidae , Fish Diseases , Helminthiasis, Animal , Parasites , Water Pollutants, Chemical , Acanthocephala/metabolism , Animals , Cyprinidae/metabolism , Environmental Monitoring/methods , Helminthiasis, Animal/metabolism , Helminthiasis, Animal/parasitology , Metals/metabolism , Water Pollutants, Chemical/toxicity
13.
Chemosphere ; 286(Pt 3): 131930, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34426290

ABSTRACT

A toxicokinetic-toxicodynamic model was constructed to delineate the exposure-response causality. The model could be used: to predict metal accumulation considering the influence of water chemistry and biotic ligand characteristics; to simulate the dynamics of subcellular partitioning considering metabolism, detoxification, and elimination; and to predict chronic toxicity as represented by biomarker responses from the concentration of metals in the fraction of potentially toxic metal. The model was calibrated with data generated from an experiment in which the Zebra mussel Dreissena polymorpha was exposed to Cu at nominal concentrations of 25 and 50 µg/L and with varied Na+ concentrations in water up to 4.0 mmol/L for 24 days. Data used in the calibration included physicochemical conditions of the exposure environment, Cu concentrations in subcellular fractions, and oxidative stress-induced responses, i.e. glutathione-S-transferase activity and lipid peroxidation. The model explained the dynamics of subcellular Cu partitioning and the effect mechanism reasonably well. With a low affinity constant for Na + binding to Cu2+ uptake sites, Na + had limited influence on Cu2+ uptake at low Na+ concentrations in water. Copper was taken up into the metabolically available pool (MAP) at a largely higher rate than into the cellular debris. Similar Cu concentrations were found in these two fractions at low exposure levels, which could be attributed to sequestration pathways (metabolism, detoxification, and elimination) in the MAP. However, such sequestration was inefficient as shown by similar Cu concentrations in detoxified fractions with increasing exposure level accompanied by the increasing Cu concentration in the MAP.


Subject(s)
Dreissena , Water Pollutants, Chemical , Animals , Copper/toxicity , Ligands , Metals , Water Pollutants, Chemical/toxicity
14.
World J Biol Psychiatry ; 23(3): 219-227, 2022 03.
Article in English | MEDLINE | ID: mdl-34449294

ABSTRACT

OBJECTIVES: Genome-Wide Association Studies (GWAS) of Schizophrenia (SCZ) have provided new biological insights; however, most cohorts are of European ancestry. As a result, derived polygenic risk scores (PRS) show decreased predictive power when applied to populations of different ancestries. We aimed to assess the feasibility of a large-scale data collection in Hanoi, Vietnam, contribute to international efforts to diversify ancestry in SCZ genetic research and examine the transferability of SCZ-PRS to individuals of Vietnamese Kinh ancestry. METHODS: In a pilot study, 368 individuals (including 190 SCZ cases) were recruited at the Hanoi Medical University's associated psychiatric hospitals and outpatient facilities. Data collection included sociodemographic data, baseline clinical data, clinical interviews assessing symptom severity and genome-wide SNP genotyping. SCZ-PRS were generated using different training data sets: (i) European, (ii) East-Asian and (iii) trans-ancestry GWAS summary statistics from the latest SCZ GWAS meta-analysis. RESULTS: SCZ-PRS significantly predicted case status in Vietnamese individuals using mixed-ancestry (R2 liability = 4.9%, p = 6.83 × 10-8), East-Asian (R2 liability = 4.5%, p = 2.73 × 10-7) and European (R2 liability = 3.8%, p = 1.79 × 10-6) discovery samples. DISCUSSION: Our results corroborate previous findings of reduced PRS predictive power across populations, highlighting the importance of ancestral diversity in GWA studies.


Subject(s)
Schizophrenia , Humans , Schizophrenia/genetics , Genome-Wide Association Study , Pilot Projects , Genetic Predisposition to Disease , Vietnam , Multifactorial Inheritance
15.
Aquat Toxicol ; 241: 106015, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34753109

ABSTRACT

A toxicokinetic-toxicodynamic model based on subcellular metal partitioning is presented for simulating chronic toxicity of copper (Cu) from the estimated concentration in the fraction of potentially toxic metal (PTM). As such, the model allows for considering the significance of different pathways of metal sequestration in predicting metal toxicity. In the metabolically available pool (MAP), excess metals above the metabolic requirements and the detoxification and elimination capacity form the PTM fraction. The reversibly and irreversibly detoxified fractions were distinguished in the biologically detoxified compartment, while responses of organisms were related to Cu accumulation in the PTM fraction. The model was calibrated using the data on Cu concentrations in subcellular fractions and physiological responses measured by the glutathione S-transferase activity and the lipid peroxidation level during 24-day exposure of the Zebra mussel to Cu at concentrations of 25 and 50 µg/L and varying Na+ concentrations up to 4.0 mmol/L. The model was capable of explaining dynamics in the subcellular Cu partitioning, e.g. the trade-off between elimination and detoxification as well as the dependence of net accumulation, elimination, detoxification, and metabolism on the exposure level. Increases in the net accumulation rate in the MAP contributed to increased concentrations of Cu in this fraction. Moreover, these results are indicative of ineffective detoxification at high exposure levels and spill-over effects of detoxification.


Subject(s)
Dreissena , Water Pollutants, Chemical , Animals , Copper/toxicity , Metals , Toxicokinetics , Water Pollutants, Chemical/toxicity
16.
Environ Pollut ; 287: 117645, 2021 Oct 15.
Article in English | MEDLINE | ID: mdl-34426373

ABSTRACT

Chronic toxicity of copper (Cu) at sublethal levels is associated with ionoregulatory disturbance and oxidative stress. These factors were considered in a toxicokinetic-toxicodynamic model in the present study. The ionoregulatory disturbance was evaluated by the activity of the Na+/K+-ATPase enzyme (NKA), while oxidative stress was presented by lipid peroxidation (LPO) and glutathione-S-transferase (GST) activity. NKA activity was related to the binding of Cu2+ and Na + to NKA. LPO and GST activity were linked with the simulated concentration of unbound Cu. The model was calibrated using previously reported data and empirical data generated when zebra mussels were exposed to Cu. The model clearly demonstrated that Cu might inhibit NKA activity by reducing the number of functional pump sites and the limited Cu-bound NKA turnover rate. An ordinary differential equation was used to describe the relationship between the simulated concentration of unbound Cu and LPO/GST activity. Although this method could not explain the fluctuations in these biomarkers during the experiment, the measurements were within the confidence interval of estimations. Model simulation consistently shows non-significant differences in LPO and GST activity at two exposure levels, similar to the empirical observation.


Subject(s)
Bivalvia , Water Pollutants, Chemical , Animals , Copper/analysis , Copper/toxicity , Homeostasis , Lipid Peroxidation , Oxidative Stress , Toxicokinetics , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicity
17.
mBio ; 12(4): e0097521, 2021 08 31.
Article in English | MEDLINE | ID: mdl-34281401

ABSTRACT

For fecal microbiota transplantation (FMT) to be successful in immune diseases like inflammatory bowel disease, it is assumed that therapeutic microbes and their beneficial functions and immune interactions must colonize a recipient patient and persist in sufficient quantity and for a sufficient period of time to produce a clinical benefit. Few studies, however, have comprehensively profiled the colonization and persistence of transferred microbes along with the transfer of their microbial functions and interactions with the host immune system. Using 16S, metagenomic, and immunoglobulin A (IgA) sequencing, we analyzed hundreds of longitudinal microbiome samples from a randomized controlled trial of 12 patients with ulcerative colitis who received fecal transplant or placebo for 12 weeks. We uncovered diverse competitive dynamics among donor and patient strains, showing that persistence of transferred microbes is far from static. Indeed, one patient experienced a dramatic loss of donor bacteria 10 weeks into the trial, coinciding with a bloom of pathogenic bacteria and worsening symptoms. We evaluated the transfer of microbial functions, including desired ones, such as butyrate production, and unintended ones, such as antibiotic resistance. By profiling bacteria coated with IgA, we identified bacteria associated with inflammation and found that microbial interactions with the host immune system can be transferred across people, which could play a role in gut microbiome therapeutics for immune-related diseases. Our findings shed light on the colonization dynamics of gut microbes and their functions in the context of FMT to treat a complex disease-information that may provide a foundation for developing more-targeted therapeutics. IMPORTANCE Fecal microbiota transplantation (FMT)-transferring fecal microbes from a healthy donor to a sick patient-has shown promise for gut diseases such as inflammatory bowel disease. Unlike pharmaceuticals, however, fecal transplants are complex mixtures of living organisms, which must then interact with the microbes and immune system of the recipient. We sought to understand these interactions by tracking the microbes of 12 inflammatory bowel disease patients who received fecal transplants for 12 weeks. We uncovered a range of dynamics. For example, one patient experienced successful transfer of donor bacteria, only to lose them after 10 weeks. We similarly evaluated transfer of microbial functions, including how they interacted with the recipient's immune system. Our findings shed light on the colonization dynamics of gut microbes, as well as their functions in the context of FMT-information that may provide a critical foundation for the development of more-targeted therapeutics.


Subject(s)
Bacteria/metabolism , Fecal Microbiota Transplantation , Feces/microbiology , Gastrointestinal Microbiome , Inflammatory Bowel Diseases/therapy , Bacteria/classification , Bacteria/genetics , Butyrates/analysis , Butyrates/metabolism , Cohort Studies , Humans , Inflammatory Bowel Diseases/microbiology , Longitudinal Studies , Metagenomics/methods
18.
Molecules ; 26(4)2021 Feb 17.
Article in English | MEDLINE | ID: mdl-33671148

ABSTRACT

NaYF4:Er,Yb upconversion luminescent nanoparticles (UCNPs) were prepared by hydrothermal methods at 180 °C for 24 h. The X-ray diffraction (XRD) and TEM (transmission electron microscopy) images show that the resulting 60 nm UCNPs possess a hexagonal structure. In this work, maleic anhydride (MA) was grafted on the surface of UCNPs to induce hydrophilic properties. The photoluminescence spectra (PL) show upconversion emissions centered around 545 nm and 660 nm under excitation at 980 nm. The luminescent inks, including UCNPs@MA, polyvinyl alcohol (PVA), deionized water (DI), and ethylene glycol (EG), exhibit suitable properties for screen printing, such as high stability, emission intensity, and tunable dynamic viscosity. The printed patterns with a height of 5 mm and a width of 1.5 mm were clearly observed under the irradiation of a 980 nm laser. Our strategy provides a new route for the controlled synthesis of hydrophilic UCNPs, and shows that the UCNPs@MAs have great potential in applications of anti-counterfeiting packing.


Subject(s)
Fluorides/chemistry , Green Chemistry Technology , Ink , Luminescence , Maleic Anhydrides/chemistry , Nanoparticles/chemistry , Spectrum Analysis , Ytterbium/chemistry , Yttrium/chemistry , Erbium/chemistry , Optical Phenomena , Polymers/chemistry , Spectroscopy, Fourier Transform Infrared , Vibration , X-Ray Diffraction
19.
Chemosphere ; 267: 129278, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33341731

ABSTRACT

The stenohaline zebra mussel, Dreissena polymorpha, is uniquely sensitive to the ionic composition of its aquatic environment. Waterborne copper (Cu) uptake and accumulation in zebra mussels were examined at various conditions in an environmentally relevant range in freshwater, i.e. Cu exposure levels (nominal concentrations of 25 and 50 µg/L), pH (5.8-8.3), and sodium (Na+) concentrations (up to 4.0 mM). Copper accumulation was simulated by a kinetic model covering two compartments, the gills and the remaining tissues. The Cu uptake rate constant decreased with decreasing pH from 8.3 down to 6.5, indicating interactions between H+ and Cu at uptake sites. The kinetic simulation showed dose-dependent effects of Na+ on Cu uptake. At 25 µg/L Cu, addition of Na+ at 0.5 mM significantly inhibited the Cu uptake rate, while no significant differences were found in the uptake rate upon further addition of Na+ up to a concentration of 4.0 mM. At 50 µg/L Cu, the Cu uptake rate was not influenced by Na+ addition. Calibration results exhibited dose-dependent elimination rates with more profound elimination with increasing exposure levels. With kinetic parameters calibrated at environmentally relevant conditions, in terms of pH and Na+ concentrations, the model performed well in predicting Cu accumulation based on independent data sets. Estimates of the Cu concentration in mussels were within a factor of 2 of the measurements. This demonstrates potential application of kinetic models that are calibrated in environmentally relevant freshwater conditions.


Subject(s)
Dreissena , Water Pollutants, Chemical , Animals , Copper/toxicity , Hydrogen-Ion Concentration , Sodium , Toxicokinetics , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicity
20.
Tob Control ; 30(5): 553-559, 2021 09.
Article in English | MEDLINE | ID: mdl-32862142

ABSTRACT

OBJECTIVES: This study quantified the secondhand smoke (SHS) concentration in a sample of public places in Vietnam to determine changes in SHS levels 5 years after a public smoking ban was implemented. METHODS: Two monitoring campaigns, one in 2013 (before the tobacco control law was implemented) and another in 2018 (5 years after the implementation of the law) were conducted in around 30 restaurants, cafeterias and coffee shops in major cities of Vietnam. Concentrations of PM2.5, as an indicator of SHS, were measured by portable particulate matter monitors (TSI SidePak AM510 and Air Visual Pro). RESULTS: The geometric mean PM2.5 concentration of all monitored venues was 87.7 µg/m3 (83.7-91.9) in the first campaign and 55.2 µg/m3 (53.7-56.7) in the second campaign. Pairwise comparison showed the PM2.5 concentrations in the smoking observed area was triple and double those in the non-smoking area and the outdoor environment. After adjusting for sampling locations and times, the SHS concentration 5 years after the implementation of the tobacco control law reduced roughly 45%. CONCLUSION: The study results indicate an improvement in air quality in public places in Vietnam via both the reduction in PM2.5 levels and the number of people observed smoking. However, greater enforcement of the free-smoke legislation is needed to eliminate SHS in public places in Vietnam.


Subject(s)
Air Pollution, Indoor , Smoke-Free Policy , Tobacco Smoke Pollution , Air Pollution, Indoor/analysis , Humans , Restaurants , Nicotiana , Tobacco Smoke Pollution/analysis , Vietnam
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