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1.
Data Brief ; 51: 109781, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38053603

RESUMO

Coffee husks are an abundant and underutilized biomass waste released from coffee production. Experimental analysis showed that coffee husks consisted of 39.2 ± 0.2 wt% cellulose, 12.6 ± 0.1 wt% hemicellulose, 23.3 ± 0.1 wt% Klason lignin, 2.9 ± 0.4 wt% acid-soluble lignin, 8.7 ± 0.2 wt% extractives, and 9.5 ± 0.2 wt% ash. Moreover, different minor elements, including K, Ca, Mg, Al, Fe, Ti, S, and Si, were found. Subsequently, coffee husks were used for the extraction of lignin using an alkaline treatment. As a result, lignin microparticles were formed with a relatively uniform size of 0.55 ± 0.11 mm. Altogether, the current article provided useful data for the valorization of coffee husks and the primary properties of lignin microparticles for further use.

2.
Ann Med Surg (Lond) ; 85(11): 5765-5769, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37915658

RESUMO

Introduction: A thrombus straddling the patent foramen ovale (PFO) is a very rare clinical entity. Optimal management remains unclear due to the availability of various therapeutic options; thus, an individualized approach is recommended. Case presentation: The authors describe a case presenting with recurrent cerebral embolism and a large and mobile thrombus straddled in the PFO. Historically, cardiac surgery, thrombolysis or anticoagulation were possible management options for this patient. However, there are no guidelines on what the optimal treatment is. Our patient was a poor surgical candidate because of advanced age and multiple comorbidities. Furthermore, she had a recent ischaemic stroke which was a relative contraindication to thrombolysis. After consulting the Heart Team, medical treatment alone with systemic anticoagulation was administered. Subsequent transthoracic echocardiography (TTE) after 1 week showed complete thrombus resolution. After 4 months, the PFO was successfully occluded with an Amplatzer device. The patient received rehabilitation therapy and had good functional recovery. Clinical discussion: Anticoagulant therapy alone was chosen because of high risk for surgery. Complete thrombus resolution was achieved after 1 week although the initial thrombus size was quite large. Nevertheless, this approach may not be applicable to every patient. In addition to TTE, multimodality imaging using transesophageal echocardiography and cardiac magnetic resonance is helpful to identify the mechanism of stroke, which in our case is a thrombus-straddled PFO, and to make early treatment decisions. Serial TTEs help assess the response to anticoagulation. An individualized approach should be made with a multidisciplinary Heart Team. Conclusion: Echocardiography plays an important role in the diagnosis and treatment evaluation for patients with a thrombus straddling a PFO. An individualized approach to manage the patient should be made with a multidisciplinary Heart Team.

3.
Bioinorg Chem Appl ; 2023: 3848456, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324575

RESUMO

Lotus seedpods (LSPs) are an abundant and underutilized agricultural residue discarded from lotus seed production. In this study, ZnCl2 and FeCl3 coactivation of LSP for one-pot preparation of magnetic activated carbon (MAC) was explored for the first time. X-ray diffraction (XRD) results showed that Fe3O4, Fe0, and ZnO crystals were formed in the LSP-derived carbon matrix. Notably, transmission electron microscopy (TEM) images showed that the shapes of these components consisted of not only nanoparticles but also nanowires. Fe and Zn contents in MAC determined by atomic absorption spectroscopy (AAS) were 6.89 and 3.94 wt%, respectively. Moreover, SBET and Vtotal of MAC prepared by coactivation with ZnCl2 and FeCl3 were 1080 m2/g and 0.51 cm3/g, which were much higher than those prepared by single activation with FeCl3 (274 m2/g and 0.14 cm3/g) or ZnCl2 (369 m2/g and 0.21 cm3/g). MAC was subsequently applied as an oxidation catalyst for Fenton-like degradation of acid orange 10 (AO10). As a result, 0.20 g/L MAC could partially remove AO10 (100 ppm) with an adsorption capacity of 78.4 mg/g at pH 3.0. When 350 ppm H2O2 was further added, AO10 was decolorized rapidly, nearly complete within 30 min, and 66% of the COD was removed in 120 min. The potent catalytic performance of MAC might come from the synergistic effect of Fe0 and Fe3O4 nanocrystals in the porous carbon support. MAC also demonstrated effective stability and reusability after five consecutive cycles, when total AO10 removal at 20 min of H2O2 addition slightly decreased from 93.9 ± 0.9% to 86.3 ± 0.8% and minimal iron leaching of 1.14 to 1.19 mg/L was detected. Interestingly, the MAC catalyst with a saturation magnetization of 3.6 emu/g was easily separated from the treated mixture for the next cycle. Overall, these findings demonstrate that magnetic activated carbon prepared from ZnCl2 and FeCl3 coactivation of lotus seedpod waste can be a low-cost catalyst for rapid degradation of acid orange 10.

4.
Microb Ecol ; 85(1): 197-208, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35034142

RESUMO

The 2,3,7,8-tetrachlorodibenzodioxin (TCDD), a contaminant in Agent Orange released during the US-Vietnam War, led to a severe environmental crisis. Approximately, 50 years have passed since the end of this war, and vegetation has gradually recovered from the pollution. Soil bacterial communities were investigated by 16S metagenomics in habitats with different vegetation physiognomies in Central Vietnam, namely, forests (S0), barren land (S1), grassland (S2), and developing woods (S3). Vegetation complexity was negatively associated with TCDD concentrations, revealing the reasoning behind the utilization of vegetation physiognomy as an indicator for ecological succession along the gradient of pollutants. Stark changes in bacterial composition were detected between S0 and S1, with an increase in Firmicutes and a decrease in Acidobacteria and Bacteroidetes. Notably, dioxin digesters Arthrobacter, Rhodococcus, Comamonadaceae, and Bacialles were detected in highly contaminated soil (S1). Along the TCDD gradients, following the dioxin decay from S1 to S2, the abundance of Firmicutes and Actinobacteria decreased, while that of Acidobacteria increased; slight changes occurred at the phylum level from S2 to S3. Although metagenomics analyses disclosed a trend toward bacterial communities before contamination with vegetation recovery, non-metric multidimensional scaling analysis unveiled a new trajectory deviating from the native state. Recovery of the bacterial community may have been hindered, as indicated by lower bacterial diversity in S3 compared to S0 due to a significant loss of bacterial taxa and recruitment of fewer colonizers. The results indicate that dioxins significantly altered the soil microbiomes into a state of disorder with a deviating trajectory in restoration.


Assuntos
Dioxinas , Microbiota , Dibenzodioxinas Policloradas , Agente Laranja , Solo , Dibenzodioxinas Policloradas/análise , Bactérias/genética , Acidobacteria/genética , Firmicutes , Microbiologia do Solo , RNA Ribossômico 16S/genética
5.
Environ Int ; 167: 107441, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35926263

RESUMO

Polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) were ubiquitous, persistent chemical compounds attached to particulate matter in the atmosphere. We aimed to study the characteristics of these pollutants in atmospheric PM2.5 of three Asian countries, including Taiwan (Taipei), Thailand (Chiang Mai), and Vietnam (Hanoi). We carried out a source apportionment analysis to determine significant PCDD/F contributors in these areas. Multiple media model was conducted to access the health impact assessment. The PM2.5 concentration in Taipei (n = 7), Chiang Mai (n = 20), and Hanoi (n = 10) were 18.4 ± 6.21 µg/m3, 133 ± 49.5 µg/m3, and 88.1 ± 12.6 µg/m3, respectively. The PCDD/Fs level in Hanoi was 92.4 ± 67.3 fg I-TEQ/m3, and in Taipei and Chiang Mai was 5.01 ± 2.39 fg I-TEQ/m3 and 14.4 ± 13.1 fg I-TEQ/m3, respectively, which showed that the higher PM2.5 concentration was not necessary to follow with higher PCDD/Fs level. In all three cities, the effect of traffic on ambient PCDD/F level was significant (23-25 %). However, we also observed the specific sources of PCDD/Fs in each city during the sampling periods, namely long-range transport (Taipei, 55 %), Biomass/open burning (Chiang Mai, 77 %), and industrial activities (Hanoi, 34 %). In the carcinogenic risk estimation, the highest median total carcinogenic risk was in Hanoi (5.87 × 10-6), followed by Chiang Mai (1.06x10-6), and Taipei (2.95 × 10-7). Although diet was the major absorption pathway, the food contributor of exposure differed among the three areas due to the difference in food consumption composition.


Assuntos
Poluentes Atmosféricos , Benzofuranos , Dibenzodioxinas Policloradas , Poluentes Atmosféricos/análise , Benzofuranos/análise , Benzofuranos/química , Dibenzofuranos/análise , Dibenzofuranos Policlorados/análise , Monitoramento Ambiental , Material Particulado/análise , Dibenzodioxinas Policloradas/análise , Tailândia
6.
Front Microbiol ; 12: 753202, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34721357

RESUMO

Eco-friendly analogs of Trichogin GA IV, a short peptaibol produced by Trichoderma longibrachiatum, were assayed against Pyricularia oryzae, the causal agent of rice blast disease. In vitro and in vivo screenings allowed us to identify six peptides able to reduce by about 70% rice blast symptoms. One of the most active peptides was selected for further studies. Microscopy analyses highlighted that the treated fungal spores could not germinate and the fluorescein-labeled peptide localized on the spore cell wall and in the agglutinated cytoplasm. Transcriptomic analysis was carried out on P. oryzae mycelium 3 h after the peptide treatment. We identified 1,410 differentially expressed genes, two-thirds of which upregulated. Among these, we found genes involved in oxidative stress response, detoxification, autophagic cell death, cell wall biogenesis, degradation and remodeling, melanin and fatty acid biosynthesis, and ion efflux transporters. Molecular data suggest that the trichogin analogs cause cell wall and membrane damages and induce autophagic cell death. Ultrastructure observations on treated conidia and hyphae confirmed the molecular data. In conclusion, these selected peptides seem to be promising alternative molecules for developing effective bio-pesticides able to control rice blast disease.

7.
RSC Adv ; 10(66): 40284-40290, 2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-35692857

RESUMO

The main protease (Mpro) of the novel coronavirus SARS-CoV-2, which has caused the COVID-19 pandemic, is responsible for the maturation of its key proteins. Thus, inhibiting SARS-CoV-2 Mpro could prevent SARS-CoV-2 from multiplying. Because new inhibitors require thorough validation, repurposing current drugs could help reduce the validation process. Many recent studies used molecular docking to screen large databases for potential inhibitors of SARS-CoV-2 Mpro. However, molecular docking does not consider molecular dynamics and thus can be prone to error. In this work, we developed a protocol using free energy perturbation (FEP) to assess the potential inhibitors of SARS-CoV-2 Mpro. First, we validated both molecular docking and FEP on a set of 11 inhibitors of SARS-CoV-2 Mpro with experimentally determined inhibitory data. The experimentally deduced binding free energy exhibits significantly stronger correlation with that predicted by FEP (R = 0.94 ± 0.04) than with that predicted by molecular docking (R = 0.82 ± 0.08). This result clearly shows that FEP is the most accurate method available to predict the binding affinity of SARS-CoV-2 Mpro + ligand complexes. We subsequently used FEP to validate the top 33 compounds screened with molecular docking from the ZINC15 database. Thirteen of these compounds were predicted to bind strongly to SARS-CoV-2 Mpro, most of which are currently used as drugs for various diseases in humans. Notably, delamanid, an anti-tuberculosis drug, was predicted to inhibit SARS-CoV-2 Mpro in the nanomolar range. Because both COVID-19 and tuberculosis are lung diseases, delamanid has higher probability to be suitable for treating COVID-19 than other predicted compounds. Analysis of the complexes of SARS-CoV-2 Mpro and the top inhibitors revealed the key residues involved in the binding, including the catalytic dyad His14 and Cys145, which is consistent with the structural studies reported recently.

8.
BMC Res Notes ; 10(1): 340, 2017 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-28750657

RESUMO

OBJECTIVE: Patients with dual hepatitis B (HBV) and hepatitis D (HDV) virus infection are at an increased risk of progression to liver cirrhosis and hepatocellular carcinoma than patients with a single viral infection. Treatment of viral hepatitis due to dual HBV/HDV infection represents a challenge. Currently there is no vaccine against HDV. Recombinant production of HDV antigen (HDAg) is the first step towards a potential vaccine candidate and the development of assays for HDV detection. RESULTS: This study demonstrates the expression of one HDAg isoform, S-HDAg, in Pichia pastoris. A recombinant vector carrying a tagged gene encoding S-HDAg under the control of the methanol-inducible promoter AOX1 was designed and integrated into P. pastoris X33. The protein, which was purified using a Ni2+ affinity column and eluted at 100-150 mM imidazole, has potential as a recombinant antigen for further study.


Assuntos
Vírus Delta da Hepatite , Antígenos da Hepatite delta , Pichia , Humanos
9.
PLoS One ; 12(4): e0175304, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28403190

RESUMO

Hepatitis D virus (HDV) infection plays an important role in liver diseases. However, the molecular epidemiology and impact of HDV infection in chronic hepatitis B (CHB) remain uncertain in Vietnam. This cross-sectional study aimed to investigate the prevalence and genotype distribution of HDV among HBsAg-positive patients in Central Vietnam. 250 CHB patients were tested for HDV using newly established HDV-specific RT-PCR techniques. HDV genotypes were determined by direct sequencing. Of the 250 patients 25 (10%) had detectable copies of HDV viral RNA. HDV-2 was predominant (20/25; 80%) followed by HDV-1 (5/25; 20%). Proven HDV genotypes share the Asian nomenclature. Chronic hepatitis B patients with concomitant HDV-1 showed higher HBV loads as compared to HDV-2 infected patients [median log10 (HBV-DNA copies/ml): 8.5 vs. 4.4, P = 0.036]. Our findings indicate that HDV infection is highly prevalent and HDV-2 is predominant in Central Vietnam. The data will add new information to the management of HBsAg-positive patients in a highly HBV endemic region to in- or exclude HDV infection in terms of diagnostic and treatment options.


Assuntos
Coinfecção/epidemiologia , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/epidemiologia , Hepatite D/epidemiologia , Vírus Delta da Hepatite/isolamento & purificação , Adolescente , Adulto , Idoso , Criança , Coinfecção/virologia , Estudos Transversais , Feminino , Genótipo , Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Hepatite D/virologia , Vírus Delta da Hepatite/genética , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Prevalência , Vietnã/epidemiologia , Adulto Jovem
10.
PLoS One ; 8(10): e78094, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24205106

RESUMO

BACKGROUND: Hepatitis D virus (HDV) infection is considered to cause more severe hepatitis than hepatitis B virus (HBV) monoinfection. With more than 9.5 million HBV-infected people, Vietnam will face an enormous health burden. The prevalence of HDV in Vietnamese HBsAg-positive patients is speculative. Therefore, we assessed the prevalence of HDV in Vietnamese patients, determined the HDV-genotype distribution and compared the findings with the clinical outcome. METHODS: 266 sera of well-characterized HBsAg-positive patients in Northern Vietnam were analysed for the presence of HDV using newly developed HDV-specific RT-PCRs. Sequencing and phylogenetic analysis were performed for HDV-genotyping. RESULTS: The HDV-genome prevalence observed in the Vietnamese HBsAg-positive patients was high with 15.4% while patients with acute hepatitis showed 43.3%. Phylogenetic analysis demonstrated a predominance of HDV-genotype 1 clustering in an Asian clade while HDV-genotype 2 could be also detected. The serum aminotransferase levels (AST, ALT) as well as total and direct bilirubin were significantly elevated in HDV-positive individuals (p<0.05). HDV loads were mainly low (<300 to 4.108 HDV-copies/ml). Of note, higher HDV loads were mainly found in HBV-genotype mix samples in contrast to single HBV-infections. In HBV/HDV-coinfections, HBV loads were significantly higher in HBV-genotype C in comparison to HBV-genotype A samples (p<0.05). CONCLUSION: HDV prevalence is high in Vietnamese individuals, especially in patients with acute hepatitis B. HDV replication activity showed a HBV-genotype dependency and could be associated with elevated liver parameters. Besides serological assays molecular tests are recommended for diagnosis of HDV. Finally, the high prevalence of HBV and HDV prompts the urgent need for HBV-vaccination coverage.


Assuntos
Antígenos de Superfície da Hepatite B/metabolismo , Hepatite D/epidemiologia , Hepatite D/virologia , Vírus Delta da Hepatite/patogenicidade , Adolescente , Adulto , Idoso , Bilirrubina/metabolismo , Feminino , Genótipo , Hepatite D/imunologia , Hepatite D/metabolismo , Vírus Delta da Hepatite/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vietnã/epidemiologia , Adulto Jovem
11.
Environ Sci Technol ; 37(8): 1493-502, 2003 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-12731829

RESUMO

Open landfill dumping areas for municipal wastes in Asian developing countries have recently received particular attention with regard to environmental pollution problems. Because of the uncontrolled burning of solid wastes, elevated contamination by various toxic chemicals including dioxins and related compounds in these dumping sites has been anticipated. In this study, concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (PCBs) were determined in soils from dumping sites in the Philippines, Cambodia, India, and Vietnam. Residue concentrations of PCDD/Fs and coplanar PCBs in dumping site soils were apparently greater than those in soils collected in agricultural or urban areas far from dumping sites, suggesting that dumping sites are potential sources of PCDD/Fs and related compounds. Observed PCDD/F concentrations in soils from dumping sites in the Philippines and Cambodia were comparable or higher than those reported for dioxin-contaminated locations in the world (e.g., near the municipal waste incinerators and open landfill dumping sites). Homologue profiles of PCDD/Fs in dumping site soils from the Philippines and, to a lesser extent, from Cambodia and India reflected patterns of samples representing typical emissions, while profiles of agricultural or urban soils were similar to those of typical environmental sinks. This result suggests recent formation of PCDD/Fs in dumping site areas and that open dumping sites are a potential source of dioxins in Asian developing countries. Uncontrolled combustions of solid wastes by waste pickers, generation of methane gas, and low-temperature burning can be major factors for the formation of dioxins in dumping sites. Elevated fluxes of PCDD/Fs to soils in dumping sites were encountered in the Philippines, Cambodia, India, and Vietnam-Hanoi, and these levels were higher than those reported for other countries. Considerable loading rates of PCDD/Fs in the dumping sites of these countries were observed, ranging from 20 to 3900 mg/yr (0.12-35 mg TEQ/yr). PCDD/F concentrations in some soil samples from the Philippines, Cambodia, India, and Vietnam-Hanoi exceeded environmental guideline values, suggesting potential health effects on humans and wildlife living near these dumping sites. The estimated intakes of dioxins via soil ingestion and dermal exposure for children were higher than those for adults, suggesting greater risk of dioxin exposure for children in dumping sites. To our knowledge, this is the first comprehensive study on PCDD/Fs contamination in open dumping sites of Asian developing countries. On the basis of the result of this study, we have addressed a new environmental issue that open dumping sites are potential sources of PCDD/Fs and related compounds, and dioxin contamination in dumping sites may become a key environmental problem in developing countries.


Assuntos
Benzofuranos/análise , Países em Desenvolvimento , Poluentes Ambientais/análise , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análogos & derivados , Dibenzodioxinas Policloradas/análise , Eliminação de Resíduos , Poluentes do Solo/análise , Administração Cutânea , Administração Oral , Adulto , Ásia , Criança , Proteção da Criança , Dibenzofuranos Policlorados , Monitoramento Ambiental , Humanos , Incineração , Medição de Risco
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