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1.
J Hazard Mater ; 421: 126684, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34339989

RESUMO

Selenium is an essential trace element for humans, animals and microorganisms. Microbial transformations, in particular, selenium dissimilatory reduction and bioremediation applications have received increasing attention in recent years. This review focuses on multiple Se-reducing pathways under anaerobic and aerobic conditions, and the phylogenetic clustering of selenium reducing enzymes that are involved in these processes. It is emphasized that a selenium reductase may have more than one metabolic function, meanwhile, there are several Se(VI) and/or Se(IV) reduction pathways in a bacterial strain. It is noted that Se(IV)-reducing efficiency is inconsistent with Se(IV) resistance in bacteria. Moreover, we discussed the links of selenium transformations to biogeochemical cycling of other elements, roles of Se-reducing bacteria in soil, plant and digestion system, and the possibility of using functional genes involved in Se transformation as biomarker in different environments. In addition, we point out the gaps and perspectives both on Se transformation mechanisms and applications in terms of bioremediation, Se fortification or dietary supplementation.


Assuntos
Selênio , Animais , Bactérias/genética , Biodegradação Ambiental , Humanos , Filogenia , Solo
2.
Gene ; 807: 145930, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34461151

RESUMO

Mitogen-activated protein kinase (MAPK) cascades have a universal cell signaling mechanism in eukaryotes. A typical MAPK signal transduction module comprises three kinds of sequentially phosphorylated protein kinases: MAPK, Mitogen-activated protein kinase kinase (MAPKK), and Mitogen-activated protein kinase kinase kinase (MAPKKK). However, little is known regarding the genes involved in MAPK cascades in Ophiocordyceps sinensis. Nine genes (three MAPK, three MAPKK, and three MAPKKK) were identified in this study. The MAPK, MAPKK, and MAPKKK genes were divided into three subfamilies, according to the phylogenetic analysis. TEY and TGY represented the activation domains of the MAPKs; the corresponding domains in MAPKKs were SDIWS and SDVWS, and those in the MAPKKs were GSVFYWMAPEV and GTPMYMSPEV. Transcription data analysis and quantitative real-time polymerase chain reaction showed that the MAPK cascade was related to the growth of the fruiting body. This is the first study to report a genome-wide identification of the MAPK, MAPKK, and MAPKK gene families in O. sinensis.


Assuntos
Cordyceps/genética , Cordyceps/metabolismo , Proteínas Serina-Treonina Quinases/genética , Análise de Dados , Expressão Gênica/genética , Perfilação da Expressão Gênica/métodos , Técnicas Genéticas , Estudo de Associação Genômica Ampla/métodos , MAP Quinase Quinase Quinases/genética , Sistema de Sinalização das MAP Quinases/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/genética , Filogenia , Proteínas Serina-Treonina Quinases/metabolismo , Reação em Cadeia da Polimerase em Tempo Real/métodos , Saccharomyces cerevisiae/genética , Transdução de Sinais/genética , Transcriptoma/genética
3.
J Environ Manage ; 301: 113851, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34597952

RESUMO

In present work, biodegradation of 4-Chlorophenol (4-CP) has been successfully achieved using bacteria i.e. Bacillus subtilis (MF447841.1), which was isolated from the wastewater of a nearby drain of Hyundai Motor Company service centre, Agartala, Tripura (India). Geonomic identification was carried out by 16 S rDNA technique and phylogenetic processes. Both, batch and column mode of experiments were performed to optimize various parameters (initial concentration, contact time, dosages etc.) involved in the significant biodegradation of 4-CP. Based on R2 value (0.9789), the Levenspiel's model was found to be best fit than others. The kinetic parameters; specific growth rate (µ), yield of cell mass (YX/S), and saturation constant (KS), were obtained as 0.6383 (h-1), 0.35 (g/g), and 0.006884 (g/L), respectively. The isolated strain has shown the ability of degrading 4-CP up to 1000 mg/L initial concentration within 40 h. Bacterial strain was immobilized via developing calcium alginate beads along by optimizing weight proportion of calcium chloride and sodium alginate and size of the bead for further experiments. Various process parameters i.e. initial feed concentration, bed height, rate of flow of were optimized during packed bed reactor (PBR) study. Maximum biodegradation efficiency of 4-CP was observed as 45.39% at initial concentration of 500 mg/L within 105 min, using 2 mm size of immobilized beads which were formed using 3.5% w/v of both calcium chloride and sodium alginate within. Thus, Bacillus subtilis (MF447841.1) could be used for biological remediation of 4-CP pollutant present in wastewater. Moreover, because of affordable and eco-friendly nature of water treatment, relatively it has the better scope of commercialization.


Assuntos
Bacillus subtilis , Reatores Biológicos , Biodegradação Ambiental , Clorofenóis , Filogenia
4.
J Environ Manage ; 301: 113887, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34610559

RESUMO

Biodegradation of pyridine starts with two mono-oxygenation reactions, and 2-hydroxyl pyridine (2-HP) accumulates as pyridine is mono-oxygenated in the first reaction. The accumulation of 2-HP inhibits both initial reactions. Therefore, selective acceleration of the second mono-oxygenation reaction should significantly enhance pyridine transformation and mineralization. Activated-sludge biomass was separately acclimated with pyridine or 2-HP to produce pyridine- and 2-HP-acclimated biomasses. The pyridine-acclimated biomass was superior for pyridine biodegradation, but the 2-HP-acclimated biomass was superior for 2-HP biodegradation. As a consequence, the pyridine-acclimated biomass by itself achieved faster mono-oxygenation of pyridine to 2-HP, but 2-HP accumulated, which limited mineralization to 60%. In contrast, mineralization reached 90% when one-third of the pyridine-acclimated was replaced with 2-HP-acclimated biomass, because 2-HP did not accumulate during pyridine biodegradation. The lack of 2-HP accumulation relieved its inhibition: e.g., the pyridine removal rates, normalized to the mass of pyridine-acclimated biomass, increased from 0.52 to 0.57 mM0.5⋅h-1 when one-third of the pyridine-acclimated biomass was replaced by 2-HP-acclimated biomass. Phylogenetic analysis showed that microbiological communities of pyridine-acclimated biomass and 2-HP-acclimated biomass differed in important ways. On the one hand, the 2-HP-acclimated biomass was richer and dominated by a rare biosphere, or genera having <0.1% of total reads. On the other hand, the most-enriched genus in the pyridine-acclimated community (Methylibium) is associated with the first mono-oxygenation of pyridine, while enriched genera in the 2-HP-acclimated community (Sediminibacterium and Dokdonella) are associated with the second mono-oxygenation of pyridine.


Assuntos
Piridinas , Esgotos , Aceleração , Biomassa , Filogenia
5.
J Hazard Mater ; 421: 126799, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34396958

RESUMO

Stack aerosols are generated within vertical building drainage stacks during the discharge of wastewater containing feces and exhaled mucus from toilets and washbasins. Fifteen stack aerosol-related outbreaks of coronavirus disease 2019 (COVID-19) in high-rise buildings have been observed in Hong Kong and Guangzhou. Currently, we investigated two such outbreaks of COVID-19 in Hong Kong, identified the probable role of chimney effect-induced airflow in a building drainage system in the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We injected tracer gas (SF6) into the drainage stacks via the water closet of the index case and monitored tracer gas concentrations in the bathrooms and along the facades of infected and non-infected flats and in roof vents. The air temperature, humidity, and pressure in vertical stacks were also monitored. The measured tracer gas distribution agreed with the observed distribution of the infected cases. Phylogenetic analysis of the SARS-CoV-2 genome sequences demonstrated clonal spread from a point source in cases along the same vertical column. The stack air pressure and temperature distributions suggested that stack aerosols can spread to indoors through pipe leaks which provide direct evidence for the long-range aerosol transmission of SARS-CoV-2 through drainage pipes via the chimney effect.


Assuntos
Aerossóis , Microbiologia do Ar , COVID-19 , Habitação , COVID-19/transmissão , Hong Kong , Humanos , Filogenia , SARS-CoV-2
6.
Gene ; 806: 145928, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34455027

RESUMO

Cytochrome P450 Family 19 (CYP19) is a crucial enzyme to catalyze the conversion of androgens to estrogens. However, the regulatory mechanism of goose CYP19 gene remains poorly understood. The present study attempted to obtain the full-length coding sequence (CDS) and 5'-flanking sequence of CYP19 gene, to investigate its expression and distribution profiles in different sized follicles, and to analyze the transcriptional regulatory mechanism of CYP19 gene in goose. Results showed that its CDS consisted of 1512 nucleotides and the encoded amino acid sequence contained a classical P450 structural domain. Homology analysis showed that there were high homologies of nucleotide and amino acid sequences between goose and other avian species. Its promoter sequence spanned from -1925 bp to the transcription start site (ATG) and several transcriptional factors were predicted in this region. Further analysis from luciferase assay showed that the luciferase activity was the highest spanning from -118 to -1 bp by constructing deletion promoter reporter vector. In addition, result from quantitative real-time polymerase chain reaction indicated that the mRNA level of CYP19 gene were highly expressed in theca layer of the fifth largest follicle, and the cellular location was in the theca externa cells by immunohistochemistry. Taken together, it could be concluded that the transcription activity of CYP19 gene was activated by transcriptional factors in its proximal region of promoter to promote the synthesis of estrogens, regulating the selection of pre-hierarchical into hierarchical follicle in goose.


Assuntos
Proteínas Aviárias/genética , Família 19 do Citocromo P450/genética , Gansos/genética , Regulação Enzimológica da Expressão Gênica , RNA Mensageiro/genética , Transcrição Genética , Sequência de Aminoácidos , Animais , Proteínas Aviárias/metabolismo , Família 19 do Citocromo P450/metabolismo , Feminino , Gansos/classificação , Regulação da Expressão Gênica no Desenvolvimento , Folículo Ovariano/citologia , Folículo Ovariano/crescimento & desenvolvimento , Folículo Ovariano/metabolismo , Filogenia , Regiões Promotoras Genéticas , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Sítio de Iniciação de Transcrição
7.
Sci Total Environ ; 803: 150027, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34482139

RESUMO

This study aims to evaluate the ecotoxicity effects of single tetracycline (TC) exposure and mixture exposure in presence of polystyrene nanoplastics (PS-NPs, 80 nm) on juvenile Ctenopharyngodon idella. We carried out single and combined exposure of TC (5000 µg/L) and PS-NPs (20, 200, 2000 µg/L) for 7 days. Compared to TC single exposure, co-exposure to PS-NPs and TC significantly changed the levels of antioxidant entities, including T-AOC, SOD, and CAT in the liver and intestine of C. idella, indicating that PS-NPs might enhance the oxidative damage caused by TC. Further, the co-exposure significantly upregulated the mRNA expression levels of MMP2, MMP9, and IL-8 in a concentration-dependent manner in the liver and intestine tissues of C. idella, compared to the control and TC single exposure groups. Moreover, the phylogenetic tree showed that MMP2 and MMP9 in C. idella are relatively conservative, and the mRNA expressions of MMP2 are significantly positively correlated with TGFß1, IL8, and MMP9 in Liver hepatocellular carcinoma (LIHC) and Colon adenocarcinoma (COAD). The above genes in LIHC and COAD were significantly correlated with various immune cells. Further, histopathological analysis revealed tissue lesions in the intestine and gill of fish in all the exposed groups, compared to the control group. In short, the present study illustrated that the toxicological effects of organic pollutants such as TC could be influenced by the presence of NPs in the C. idella.


Assuntos
Carpas , Doenças dos Peixes , Ração Animal/análise , Animais , Dieta , Proteínas de Peixes/genética , Microplásticos , Filogenia , Poliestirenos/toxicidade , Tetraciclina
8.
J Med Virol ; 94(1): 413-416, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34515998

RESUMO

In December 2020, Italy experienced the first case of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) B.1.1.7 lineage. In January 2021, we identified 21 cases of this variant in Corzano, defining the first outbreak of SARS-CoV-2 B.1.1.7 lineage in Italy. The high transmissibility of the B.1.1.7 variant represented an important benefit for the virus, which became rapidly dominant on the territory. Containment measures induced the epidemic curve onto a decreasing trajectory underlining the importance of appropriate control and surveillance for restraint of virus spread. Highlights The first Italian outbreak of SARS-CoV-2 B.1.1.7 lineage occurred in Lombardy in January 2021. The outbreak originated by a single introduction of the B.1.1.7 lineage. The genomic sequencing revealed, for the first time, the presence of the V551F mutation in the B.1.1.7 lineage in Italy. Surveillance, prompt sequencing and tracing efforts were fundamental to identify and to quickly contain the outbreak.


Assuntos
Teste de Ácido Nucleico para COVID-19 , COVID-19/epidemiologia , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Adolescente , Adulto , COVID-19/transmissão , Criança , Pré-Escolar , Surtos de Doenças/estatística & dados numéricos , Feminino , Genoma Viral/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Controle de Infecções/métodos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Filogenia , Análise de Sequência de RNA , Sequenciamento Completo do Genoma , Adulto Jovem
9.
Parasitol Int ; 86: 102470, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34560288

RESUMO

During an investigation of parasitic ciliates in northern China, two Trichodina species, T. acuta Lom, 1970 and T. nigra Lom, 1960, were isolated from the freshwater fish Cyprinus carpio Linnaeus, 1758. The morphology of each species was investigated based on dry silver nitrate-stained specimens. In addition, the molecular phylogeny of each was analyzed based on small subunit ribosomal DNA (SSU rDNA) sequence data. Trichodina acuta can be distinguished from its congeners by the undefined periphery of the central circle, the distinct gap between the rays and the central circle, and the distinctly sickle-shaped blades. Trichodina nigra is a cosmopolitan ciliate and is characterized by its densely linked denticles, broad, rounded spatula-shaped blades, robust central parts, and well developed rays. Phylogenetic analyses revealed that T. acuta and T. nigra nest within different clades, supporting the assertion that the GC content of SSU rDNA sequences could reflect evolutionary relationships among Trichodina species.


Assuntos
Carpas , Infecções por Cilióforos/veterinária , Doenças dos Peixes/epidemiologia , Oligoimenóforos/classificação , Animais , China/epidemiologia , Infecções por Cilióforos/epidemiologia , Infecções por Cilióforos/parasitologia , Doenças dos Peixes/parasitologia , Oligoimenóforos/citologia , Oligoimenóforos/genética , Oligoimenóforos/isolamento & purificação , Filogenia , Prevalência
10.
Parasitol Int ; 86: 102473, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34600157

RESUMO

Despite the large number of species described to date for the onchoprotepcephalid genus Acanthobothrium (207), only 16 named species have a genetic sequence. With this background, specimens of adult cestodes of the stingray Hypanus longus were collected off San Blas, Nayarit, and onchoproteocephalid larvae in the carangid fish Trachinotus rhodopus from Puerto Ángel, Oaxaca, both located on the Pacific coast of Mexico. The objective of this work is to investigate the phylogenetic position of these adults and larvae using nuclear ribosomal markers (18S rDNA and 28S rDNA). Morphologically, adult specimens were identified as Acanthobothrium cleofanus; larvae were identified only to family level. The phylogenetic position of both taxa was investigated based on the information of two nuclear molecular markers analyzed under Parsimony (PA) and Bayesian Inference (BI) methods. The newly generated sequences of A. cleofanus from Nayarit are identical to the sequences of several samples of Acanthobothrium sp. collected in the Mexican Pacific, which sequence are available in GenBank; DNA sequences obtained from onchoproteocephalid larva clearly place this taxon within Acanthobothrium but representing an independent lineage. In the resulting phylogenetic trees, Uncibilocularis okei was found nested within Acanthobothrium with an unstable position depending on the optimality criteria, indicating the need for more molecular analyzes with a greater number of species of both genera prior to define its phylogenetic relationships.


Assuntos
Cestoides/classificação , Infecções por Cestoides/veterinária , Doenças dos Peixes/parasitologia , Rajidae , Animais , Cestoides/genética , Cestoides/crescimento & desenvolvimento , Infecções por Cestoides/parasitologia , Marcadores Genéticos , Larva/classificação , Larva/crescimento & desenvolvimento , México , Filogenia , RNA Ribossômico 18S/análise , RNA Ribossômico 28S/análise
11.
Sci Total Environ ; 803: 150108, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34525766

RESUMO

The anaerobic membrane bioreactor (AnMBR) has considerable potential for treating wastewater, although there is very little data on the effect of antibiotics on AnMBR performance. This study examined the effect of Ciprofloxacin (CIP) - an antibiotic that can occur at high concentrations, and has a substantial impact on ecosystems, on AnMBR performance. The long-term (44 days) presence of 0.5 mg/L CIP in the feed did not have a strong effect on COD removal, volatile fatty acid (VFA) accumulation, or methane yield, but did affect the pH, soluble microbial products (SMPs) and suspended solids. However, at 4.7 mg/L CIP, a significant effect on all the parameters tested was seen. 16S rRNA gene-based community analysis demonstrated that CIP changed the phylogenetic structure and altered the species richness and diversity. The relative abundance of various genera was also changed, and this explained much of the change in AnMBR behavior.


Assuntos
Ciprofloxacina , Ecossistema , Anaerobiose , Reatores Biológicos , Membranas Artificiais , Metano , Filogenia , RNA Ribossômico 16S/genética , Esgotos , Eliminação de Resíduos Líquidos , Águas Residuárias
12.
Sci Total Environ ; 802: 149755, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34525767

RESUMO

Derived from their great capacity of adaptation, microalgae have several industrial applications, including pigment production for nutraceutical sector. However, the scarcity of studies on the diversity and life histories from several environments, highlight the need for more research on new species and habitats. Based on this, the present study assessed the microalgal diversity in water bodies of a municipal solid waste (MSW) landfill in Asturias (Spain). A total of 14 strains were successfully isolated and scaled up in liquid monocultures. They were identified through a combination of morphologic features with molecular assignation by DNA barcoding via the 18S and ITS1-5.8S-ITS2 genes. The results of the genetic procedures (BLAST assignments and the 18S and ITS1-5.8S-ITS2 genealogies) showed that 10 of the 14 assayed isolates were identified at the species level. The available genetic data were not sufficient for species classifications of the remaining isolates. It is possible that some might be new species not previously studied or described. Indeed, a new species, Coelastrella cogersae, was proposed in this study. Moreover, 3 of the 14 isolates (including the newly proposed species) exhibited caretogenic activity under specific conditions during the culture. These results are a great step forward in both the screening of lesser-known environments and the discovery of new sources of bioactive compounds. The study could be of great value to the nutraceutical industries and markets.


Assuntos
Microalgas , Carotenoides , Microalgas/genética , Filogenia , Resíduos Sólidos , Espanha , Instalações de Eliminação de Resíduos
13.
Sci Total Environ ; 802: 149862, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34461473

RESUMO

Complete ammonia oxidizing (comammox) bacteria are frequently detected in wastewater biological nutrient removal (BNR) systems. This study identified "Candidatus Nitrospira nitrosa"-like comammox bacteria as the predominant ammonia oxidizers (97.5-99.4%) in a lab-scale BNR system with acetate and sludge fermentation liquid as external carbon sources. The total nitrogen and phosphorus removals of the system were 75.9% and 86.9% with minimal N2O emission (0.27%). Low ammonia concentration, mixotrophic growth potentials and metabolic interactions with diverse heterotrophs collectively contributed to the survival of comammox bacteria in the system. The recovered draft genomes of comammox bacteria indicated their potentials in using acetate and propionate but not butyrate. Acetate and propionate indeed stimulated the transcription of comammox amoA genes (up-regulated by 4.1 folds compared with no organic addition), which was positively correlated with the ammonia oxidation rate of the community (r = 0.75, p < 0.05). Comammox bacteria could provide vitamins/cofactors (e.g., cobalamin and biotin) to heterotrophs (e.g., Burkholderiaceae), and in return receive amino acids (e.g., phenylalanine and tyrosine) from heterotrophs, which they cannot synthesize. Compared with comammox bacteria, ammonia oxidizing bacteria (AOB) exhibited lower metabolic versatility, and lacked more pathways for the synthesis of amino acids and vitamin/cofactors, leading to their washout in the studied system. BNRs with comammox bacteria as the major nitrifiers hold great potentials in achieving superior performance at low aeration cost and low N2O emission and at full-scale plants.


Assuntos
Esgotos , Águas Residuárias , Amônia , Bactérias/genética , Carbono , Fermentação , Nitrificação , Nutrientes , Oxirredução , Filogenia
14.
J Infect Chemother ; 28(1): 82-86, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34412982

RESUMO

Hepatitis B virus (HBV) DNA is detectable in the nails and hair of patients with chronic HBV infection. However, it remains unclear whether HBV DNA can be detectable in the nails and hair of patients with acute HBV infection. We encountered two cases of children with acute HBV infection. HBV DNA in the nails and hair from the two children was evaluated by real-time PCR. To clarify the characteristics of HBV DNA, full-length HBV genome sequencing and phylogenetic tree analysis were performed. The levels of serum HBV DNA in children of cases 1 and 2 at day 0 were 7.6 Log IU/mL and 7.4 Log IU/mL, respectively. Nail HBV DNA was detected in both children (case 1: 4.6 Log IU/mL at day 0, case 2: 5.5 Log IU/mL at day 14). Moreover, hair HBV DNA was detectable in case 2 (4.0 Log IU/mL at day 14). Serum HBV DNA became undetectable within approximately 3-4 months after the first hospital visit. After the resolution of HBV viremia, nail and hair HBV DNA became undetectable. The sequence analysis of serum, nail and hair HBV DNA showed the same HBV genotype in each case (case1: genotype C, case 2: genotype A). In case 1, 3 nucleotides were different in the full-genome HBV sequence between the serum and nails. In case 2, the full-genome HBV sequences were identical among the serum, nails and hair. In conclusion, HBV DNA was detectable in nails and hair of children with acute HBV infection.


Assuntos
Hepatite B Crônica , Hepatite B , Criança , DNA Viral/genética , Genótipo , Hepatite B/diagnóstico , Antígenos de Superfície da Hepatite B , Antígenos E da Hepatite B , Vírus da Hepatite B/genética , Humanos , Unhas , Filogenia
15.
J Med Virol ; 94(1): 161-172, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34415583

RESUMO

Detailed information on intrahost viral evolution in SARS-CoV-2 with and without treatment is limited. Sequential viral loads and deep sequencing of SARS-CoV-2 from the upper respiratory tract of nine hospitalized children, three of whom were treated with remdesivir, revealed that remdesivir treatment suppressed viral load in one patient but not in a second infected with an identical strain without any evidence of drug resistance found. Reduced levels of subgenomic RNA during treatment of the second patient, suggest an additional effect of remdesivir on viral replication. Haplotype reconstruction uncovered persistent SARS-CoV-2 variant genotypes in four patients. These likely arose from within-host evolution, although superinfection cannot be excluded in one case. Although our dataset is small, observed sample-to-sample heterogeneity in variant frequencies across four of nine patients suggests the presence of discrete viral populations in the lung with incomplete population sampling in diagnostic swabs. Such compartmentalization could compromise the penetration of remdesivir into the lung, limiting the drugs in vivo efficacy, as has been observed in other lung infections.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Antivirais/uso terapêutico , COVID-19/tratamento farmacológico , COVID-19/virologia , Evolução Molecular , SARS-CoV-2/genética , Monofosfato de Adenosina/uso terapêutico , Adolescente , Alanina/uso terapêutico , Criança , Pré-Escolar , Farmacorresistência Viral , Feminino , Haplótipos , Humanos , Lactente , Pulmão/virologia , Masculino , Filogenia , RNA Viral/análise , RNA Viral/genética , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/fisiologia , Carga Viral , Replicação Viral/efeitos dos fármacos
16.
Parasitol Int ; 86: 102477, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34619383

RESUMO

Babesia gibsoni, the causative agent of canine piroplasmosis, is a tick-borne intraerythrocytic protozoan parasite predominantly reported in Asian countries. The present study aimed at genotypic characterization of B. gibsoni isolates prevalent in dogs in Kerala, a southern state of India. Blood samples were collected from 272 dogs in Kerala and B. gibsoni infection was detected by microscopy and polymerase chain reaction (PCR). Molecular confirmation of B. gibsoni parasites was carried out by 18S rRNA nested-PCR, followed by sequencing. Nested-PCR detected a higher percentage of dogs (40.44%) positive for B. gibsoni infection than microscopy where 15.81% dogs were detected positive for infection. Genetic characterization of B. gibsoni isolates (n = 11) prevalent in dogs in the state of Kerala was carried out by PCR amplification and sequencing of the 855 bp thrombospondin-related adhesive protein (TRAP) gene fragment. Phylogenetic analysis of the B. gibsoni TRAP (BgTRAP) gene revealed that B. gibsoni isolates from Kerala formed a distinct cluster with the isolates from north India and Bangladesh, away from other East Asian isolates. Nucleotide analysis of the tandem repeats of BgTRAP gene showed considerable genetic variation among Indian isolates that was shared by B. gibsoni isolates of Bangladesh but not by the isolates of East Asian countries. The results of the present study further confirmed that B. gibsoni parasites in a distinct genetic clade are endemic in dogs in India and Bangladesh. However, elaborate studies are required for better understanding of the genetic diversity of B. gibsoni.


Assuntos
Babesia/isolamento & purificação , Babesiose/epidemiologia , Doenças do Cão/epidemiologia , Variação Genética , Filogenia , Animais , Babesia/genética , Babesiose/parasitologia , Doenças do Cão/parasitologia , Cães , Índia/epidemiologia , Prevalência , Proteínas de Protozoários/análise , Trombospondinas/análise
17.
Sci Total Environ ; 802: 149848, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34464803

RESUMO

Vegetated coastal ecosystems (VCEs; i.e., mangroves, saltmarshes, and seagrasses) represent important sources of natural methane emission. Despite recent advances in the understanding of novel taxa and pathways associated with methanogenesis in these ecosystems, the key methanogenic players and the contribution of different substrates to methane formation remain elusive. Here, we systematically investigate the community and activity of methanogens using publicly available metatranscriptomes at a global scale together with our in-house metatranscriptomic dataset. Taxonomic profiling reveals that 13 groups of methanogenic archaea were transcribed in the investigated VCEs, and they were predominated by Methanosarcinales. Among these VCEs, methanogens exhibited all the three known methanogenic pathways in some mangrove sediments, where methylotrophic methanogens Methanosarcinales/Methanomassiliicoccales grew on diverse methyl compounds and coexisted with hydrogenotrophic (mainly Methanomicrobiales) and acetoclastic (mainly Methanothrix) methanogens. Contrastingly, the predominant methanogenic pathway in saltmarshes and seagrasses was constrained to methylotrophic methanogenesis. These findings reveal different archaeal methanogens in VCEs and suggest the potentially distinct methanogenesis contributions in these VCEs to the global warming.


Assuntos
Archaea , Ecossistema , Archaea/genética , Metano , Methanosarcinaceae , Methanosarcinales , Filogenia
18.
Trop Anim Health Prod ; 53(6): 528, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34725745

RESUMO

The aim of this study was to estimate the molecular prevalence of Toxoplasma gondii, Neospora caninum and the co-infection by both Apicomplexan parasites in uterus tissues of cows. PCR was used to detect T. gondii and N. caninum DNA in uterus from 140 uteri of slaughtered cows in the regional slaughterhouse of Béja (Northwest Tunisia). Positive PCR products were sequenced and used for the phylogenetic analysis. The overall molecular prevalence of T. gondii and N. caninum in cows' uterus was 5 and 15.57%, respectively. Co-infection prevalence by the two parasites was estimated to be 2.85%. Risk factors including the age categories significantly affected the molecular prevalence of T. gondii and N. caninum in cows' uterus. The highest molecular prevalence of T. gondii (11.5 ± 3.1) and N. caninum (21.1 ± 11.1; p = 0.038) was observed in cows aged of more than 8 years. There were no differences depicted according to cow's breeds and localities. Comparison of the partial sequences of the ITS1 gene revealed 100% similarity among our N. caninum sequence (MW136256) and those deposited in GenBank. The T. gondii sequence described in this study (MW260335) was 99.4-100% homologous to T. gondii sequences published in the GenBank.To the best of our knowledge, this is the first molecular evidence of N. caninum and T. gondii co-infection in naturally infected cows in North Africa. This information is pertinent in designing control programmes that would reduce economic losses in the livestock industry.


Assuntos
Coccidiose , Coinfecção , Neospora , Toxoplasma , Toxoplasmose Animal , Animais , Anticorpos Antiprotozoários , Bovinos , Coccidiose/epidemiologia , Coccidiose/veterinária , Coinfecção/epidemiologia , Coinfecção/veterinária , Feminino , Genitália , Neospora/genética , Filogenia , Estudos Soroepidemiológicos , Toxoplasma/genética , Toxoplasmose Animal/epidemiologia , Tunísia/epidemiologia
19.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(10): 1027-1032, 2021 Oct 15.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-34719418

RESUMO

OBJECTIVES: To study the molecular epidemiological characteristics of norovirus in children with acute gastroenteritis from 2017 to 2019. METHODS: A retrospective analysis was performed on the medical data of children with acute gastroenteritis who were admitted to Children's Hospital of Chongqing Medical University from January 2017 to December 2019. A total of 1 458 stool samples were collected from the children, and viral RNA was extracted. Reverse transcription polymerase chain reaction was used for gene amplification, sequencing, and genotype identification of the VP1 region of capsid protein in norovirus. RESULTS: Among the 1 458 stool samples, 158 (10.8%) were positive for norovirus. There was no significant difference in the positive detection rate of norovirus between different years (P>0.05). Boys had a norovirus detection rate of 12.2% (105/860), which was significantly higher than that in girls (8.9%, 53/598) (P=0.043). The children aged 12 to <18 months had the highest norovirus detection rate (16.9%, 51/301). August, September, and October were the epidemic peak season. A total of 23 norovirus-positive samples were also positive for rotavirus. The norovirus detected were mainly GII type (97.5%, 154/158), and only 4 cases were GI type (2.5%, 4/158). The sequencing of the VP1 region of capsid protein in the positive samples showed that GII.4 (69.6%, 110/158) was the dominant genotype, among which 99 (62.7%, 99/158) were GII.4 Sydney 2012, followed by GII.3 (15.2%, 24/158), GII.2 (10.1%, 16/158), GII.6 (1.9%, 3/158), and GII.17 (0.6%, 1/158). GI.3 (1.3%, 2/158), GI.2 (0.6%, 1/158), and GI.5 (0.6%, 1/158) were rarely detected. CONCLUSIONS: Norovirus GII.4 Sydney 2012 was the major epidemic strain in the children with norovirus gastroenteritis from 2017 to 2019. Although norovirus infection can exist throughout the year, August to October is the peak period. During this period, norovirus surveillance and key population protection are strengthened to help prevent and control norovirus diarrhea.


Assuntos
Gastroenterite , Norovirus , Criança , Fezes , Feminino , Gastroenterite/epidemiologia , Humanos , Masculino , Norovirus/genética , Filogenia , Estudos Retrospectivos
20.
Rev Bras Parasitol Vet ; 30(4): e012721, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34755807

RESUMO

This study aimed to investigate the genetic diversity of Hepatozoon spp. in rodents from Valdivia, Chile. A total of 74 rodents (synanthropic n=38; wild n=36) were trapped in Valdivia. We performed conventional PCR assays for Apicomplexa organisms targeting two overlapping 18S rDNA gene fragments (600 bp and 900 bp) followed by sequencing of selected amplicons. Hepatozoon spp. occurrence was 82.43% (61/74). Twelve sequences obtained from the 600 bp and ten from the 900 bp 18S rDNA fragments were identified as Hepatozoon sp. Six sequences obtained from 18S rDNA-based overlapping PCR protocols were used for concatenated (1,400 bp) phylogenetic, haplotype and distance analyses. Hepatozoon spp. 18S rDNA concatenated sequences from the present study were detected in Oligoryzomys longicaudatus, Rattus norvegicus, Mus musculus, and Abrothrix longipilis grouped with Hepatozoon species earlier described in rodents and reptiles from Chile and Brazil. Nucleotide polymorphism of the six 18S rDNA sequences (1,400 bp) from this study, and other Chilean sequences from rodents and rodent's ticks, showed high diversity with a total of nine Chilean haplotypes. Three haplotypes from Valdivia were identified for the first time in this study, suggesting the circulation of novel haplotypes in rodents from southern Chile.


Assuntos
Eucoccidiida , Roedores , Animais , Chile , Eucoccidiida/genética , Variação Genética , Camundongos , Filogenia , RNA Ribossômico 18S/genética , Ratos
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