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1.
J Chem Phys ; 158(22)2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37290079

RESUMO

In this study, we investigate the energetics of small aluminum clusters doped with a carbon atom using several computational methods, including diffusion quantum Monte Carlo, Hartree-Fock (HF), and density functional theory. We calculate the lowest energy structure, total ground-state energy, electron population distribution, binding energy, and dissociation energy as a function of the cluster size of the carbon-doped aluminum clusters compared with the undoped ones. The obtained results show that carbon doping enhances the stability of the clusters mainly due to the electrostatic and exchange interactions from the HF contribution gain. The calculations also indicate that the dissociation energy required to remove the doped carbon atom is much larger than that required to remove an aluminum atom from the doped clusters. In general, our results are consistent with available theoretical and experimental data.


Assuntos
Alumínio , Teoria Quântica , Alumínio/química , Método de Monte Carlo , Difusão , Elétrons
2.
Phys Chem Chem Phys ; 24(5): 3119-3128, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35040859

RESUMO

We present all-electron quantum Monte Carlo simulations on the anionic, neutral, and cationic boron clusters BQn with up to 13 atoms (Q = -1, 0, +1 and n ≤ 13). Accurate total energies of these clusters are obtained and an excellent agreement is reached with available experimental results for adiabatic and vertical detachment energies. We also perform very accurate Hartree-Fock calculations in the complete-basis-set limit where electron correlation is absent. In combination with the FN-DMC and HF-CBS results, we quantify the correlation effects and present the first attempt for a systematic investigation on the electron correlation effects in boron clusters. The obtained results show that, in general, electron correlation may contribute significantly to both the atomic and electronic structures of the boron clusters, manifested in the quantities such as the average binding energies of the clusters, atomic dissociation energies, detachment energies, and ionization potentials. For instance, the calculations indicate that the electron correlation maintains the bound state of cationic cluster B2+ and it also contributes 99% of the detachment energy of the anionic cluster B5-.

3.
Cryo Letters ; 43(2): 110-119, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36626152

RESUMO

BACKGROUND: Using sulfated polysaccharides (SP) in fish sperm freezing medium promotes cell maintenance. OBJECTIVE: To evaluate the effect of different SP concentrations, extracted from two seaweeds (Gracilaria domingensis and Ulva fasciata), as a supplement to the sperm freezing medium of Prochilodus brevis. MATERIALS AND METHODS: Five semen pools were diluted in a solution composed of 5% glucose, 10 % dimethyl sulfoxide (DMSO) and different SP concentrations (0, 0.5, 1.0, 1.5, 2.0, 2.5 or 3.0 mg/mL). The samples were cryopreserved and, after 7 days, rewarmed and analyzed for morphology, plasma membrane integrity, DNA integrity, mitochondrial activity and sperm kinetics [total motility, progressive motility, curvilinear velocity (VCL), straight line velocity (VSL), average path velocity (VAP), linearity (LIN), and wobble (WOB)]. RESULTS: There was no interaction between seaweed and SP concentrations. Similar effects were observed with SP extracted from the two seaweeds, regardless of concentration. When comparing the SP concentrations, regardless of the seaweed, 1.0 mg/mL SP showed better results for VCL and VSL. For VAP and WOB, 1.0 mg/mL SP showed better results, but differed from 3.0 mg/mL. LIN followed the same pattern, but differed from SP at 2.5 and 3.0 mg/mL. For progressive motility, 1.0 mg/mL G. domingensis showed superior results compared to the control. For mitochondrial activity, G. domingensis was superior to U. fasciata, regardless of concentration. The lowest concentrations (0.5 and 1.0 mg/mL) showed the best results, regardless of the seaweed. However, the control was superior to all treatments tested. CONCLUSION: G. domingensis SP at the lowest concentrations might be a potential supplement to the P. brevis freezing medium. doi.org/10.54680/fr22210110412.


Assuntos
Caraciformes , Preservação da Fertilidade , Preservação do Sêmen , Animais , Masculino , Congelamento , Criopreservação/métodos , Sulfatos , Motilidade dos Espermatozoides , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Espermatozoides , Glucose
4.
Phys Chem Chem Phys ; 23(16): 9832-9842, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33908436

RESUMO

We investigate many-electron correlation effects in neutral and charged coinage-metal clusters Cun, Agn, and Aun (n = 1-4) via ab initio calculations using fixed-node diffusion Monte Carlo (FN-DMC) simulations, density functional theory (DFT), and the Hartree-Fock (HF) method. From very accurate FN-DMC total energies of the clusters and the HF results in the infinity large complete-basis-set limit, we obtain correlation energies in these strongly correlated many-electron clusters involving d orbitals. The obtained bond lengths of the clusters, atomic binding and dissociation energies, ionization potentials, and electron affinities are in satisfactory agreement with the available experiments. In the analysis, the electron correlation effects on these observable physical quantities are quantified by relative correlation contributions determined by the difference between the calculated FN-DMC and HF results. We show that the correlation contribution is not only significant for the quantities related to electronic structures of the coinage-metal clusters, such as electron affinity, but it is also essential for the stability of the atomic structures of these clusters. For example, the electron correlation contribution is responsible for more than 90% of the atomic binding energies of the small neutral copper clusters. We also demonstrate the orbital-occupation dependence of the correlation energy and electron pairing of the valence electrons in these coinage-metal clusters from the electron correlation-energy gain and spin-multiplicity change in the electron addition processes, which are reflected in their ionization potentials and electron affinities.

5.
J Chem Phys ; 151(1): 014303, 2019 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-31272165

RESUMO

Using the fixed-node diffusion Monte Carlo (FN-DMC) method, we calculate the total energy of small lithium clusters Lin (n = 2-6) to obtain the many-body decomposition of the interaction energy of 2- up to 6-body interactions. The obtained many-body decomposition of the interaction energy shows an alternating series with even and odd terms of attractive and repulsive contributions, respectively. The two-body attractive interactions guarantee the stability of the Li2, Li3, and Li4 clusters. For larger clusters Li5 and Li6, the 4-body attractive interactions are required for their stabilization once the strength of the 3-body repulsive interactions overwhelms that of the 2-body attractive ones. With increasing the cluster size, the additive and nonadditive contributions to the interaction energy increase linearly in magnitude but with different slopes for the two-dimensional (2D) planar and three-dimensional (3D) cagelike clusters. The significant increment in nonadditive effects from the 4-atom to the 5-atom cluster has driven the structural transition from 2D to 3D. Combining the FN-DMC calculations with the Hartree-Fock many-body decomposition of the interaction energy, we extract the correlation effects, showing that an odd-even competition pattern in the many-body repulsive and attractive interactions is crucial for the stabilization of the clusters.

6.
J Chem Phys ; 149(21): 214303, 2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30525724

RESUMO

The valence electron binding energies and the aromaticity of neutral and charged small boron clusters with three and four atoms are investigated using a combination of the fixed-node diffusion quantum Monte Carlo (FN-DMC) method, the density functional theory, and the Hartree-Fock approximation. The obtained electron binding energies such as the adiabatic detachment energy, vertical detachment energy, adiabatic ionization potential, and the vertical ionization potential are in excellent agreement with available experimental measurements. Their decomposition into three physical components such as the electrostatic potential and exchange interaction, the relaxation energy, and the electronic correlation effects has allowed us to determine that the neutral boron clusters are stabilized by the electrostatic and exchange interactions, while the anionic ones are stabilized by the relaxation and correlation effects. The aromaticity is studied based on electronic structure principles descriptor and on the resonance energy. The FN-DMC results from the electronic structure principles of the energy, hardness, and eletrophilicity have supported the aromaticity of B 3 - , B 4 - , and B4 and partially supported the aromaticity of the clusters B3, B 3 + , and B 4 + . The obtained values for the resonance energy of the clusters B 3 - , B3, B 3 + , B4, B 4 + , and B 4 - are 55.1(7), 54.2(8), 33.9(7), 84(1), 67(1), and 58(1) kcal/mol, respectively. Therefore, the order of decreasing stability of the trimer is B 3 - > B 3 > B 3 + , while for the tetramer it is B 4 > B 4 + > B 4 - , which is in agreement with the results from the molecular orbital analysis.

7.
J Chem Phys ; 146(17): 174306, 2017 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-28477597

RESUMO

Using the fixed-node diffusion quantum Monte Carlo method, we calculate the total energy of small cationic and neutral lithium clusters. We estimate the ionization potential, atomic binding energy, dissociation energy, and the second difference in energy. We present a critical analysis of the structural and electronic properties of the clusters. The bond lengths and binding and dissociation energies obtained from the calculations are in excellent agreement with the available experimental results. A comparative analysis of the dissociation energy and the second difference in energy indicates that the cationic clusters Li3+, Li5+, and Li7+ are the most stable ones. We have also studied the electron correlation effects in the lithium clusters. The cationic clusters of odd-number size are relatively more favored in terms of correlation energy than their neighbors of even-number size. In the range of cluster sizes under investigation, we find that the contribution of electron correlation to ionization potential is not larger than 28% of its total values, whereas it enhances significantly the dissociation energy of the clusters reaching up to 70% of its total values for the most stable ones.

8.
J Comput Chem ; 37(17): 1531-6, 2016 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-26992447

RESUMO

An investigation of the energetics of small lithium clusters doped either with a hydrogen or with a fluorine atom as a function of the number of lithium atoms using fixed-node diffusion quantum Monte Carlo (DMC) simulation is reported. It is found that the binding energy (BE) for the doped clusters increases in absolute values leading to a more stable system than for the pure ones in excellent agreement with available experimental measurements. The BE increases for pure, remains almost constant for hydrogenated, and decreases rapidly toward the bulk lithium for the fluoride as a function of the number of lithium atoms in the clusters. The BE, dissociation energy as well as the second difference in energy display a pronounced odd-even oscillation with the number of lithium atoms. The electron correlation inverts the odd-even oscillation pattern for the doped in comparison with the pure clusters and has an impact of 29%-83% to the BE being higher in the pure cluster followed by the hydrogenated and then by the fluoride. The dissociation energy and the second difference in energy indicate that the doped cluster Li3 H is the most stable whereas among the pure ones the more stable are Li2 , Li4 , and Li6 . The electron correlation energy is crucial for the stabilization of Li3 H. © 2016 Wiley Periodicals, Inc.

9.
Aust Vet J ; 102(1-2): 11-18, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37814548

RESUMO

BACKGROUND: Infectious viral diseases in dairy cattle have substantial implications for milk production, quality and overall animal health. Diagnostic tools providing reliable results are crucial for effective disease control at the farm and industry level. Pooled or bulk tank milk (BTM) can be used as a cost-effective aggregate sample to assess herd disease status in dairy farms. FINDINGS: Detection of pathogens or specific antibodies in milk can be used for monitoring endemic diseases within-farm, region or country-level disease surveillance and to make informed decisions on farm management. The suitability of assays applied to pooled milk samples relies on validation data of fit-for-purpose tests to design an optimal testing strategy. Diverse approaches and variable scope of studies determining test accuracy need to be critically appraised before sourcing the parameters to design sampling strategies and interpreting surveys. Determining if BTM or pooled milk is the best approach for a disease management programme should carefully consider several aspects that will impact the accuracy and interpretation, for example, the size of the lactating herd, the risk of infection in the lactating and non-lactating groups, the expected within-herd prevalence, the duration of infection, the duration and concentration of antibodies in milk and use of vaccination. CONCLUSIONS: There are examples of tests on BTM samples providing efficient assessments of the herd disease status and supporting disease control programmes for viral diseases. However, challenges arise in pooled milk testing due to the need for accurate estimates of the imperfect sensitivity and specificity of the assays. Integration of new biotechnologies could enhance multiplexing and data interpretation for comprehensive surveillance. The development of highly sensitive assays is necessary to meet the demands of larger dairy herds and improve disease detection and assessment.


Assuntos
Doenças dos Bovinos , Viroses , Feminino , Bovinos , Animais , Leite , Lactação , Ensaio de Imunoadsorção Enzimática/veterinária , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/prevenção & controle , Doenças dos Bovinos/epidemiologia , Viroses/veterinária , Indústria de Laticínios
10.
Eur Arch Paediatr Dent ; 25(1): 3-16, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37651073

RESUMO

PURPOSE: In recent years, minimal intervention procedures (MIPs) for treating dental caries in children have stood out as an innovative method. Nevertheless, the treatment decision should be based on scientific evidence, professional expertise, and parents' preference/acceptance. Evaluating the acceptance of MIPs by parents is an essential factor, but little information is available on what guides this preference. METHODS: This scoping review aims to synthesize the evidence on parents'/caregivers' acceptance of MIP for managing cavitated caries lesions in children. A search was performed in the PubMed, Cochrane Library, Lilacs and Google Scholar databases with no restriction on date or language. RESULTS: A total of 19 articles were selected (6 clinical trials, 1 longitudinal and 12 cross-sectional studies). The application of silver diamino fluoride (SDF) was the most commonly evaluated procedure (n = 17), followed by the atraumatic restorative technique (ART) and the Hall Technique (HT). The acceptance of MIPs ranged from 1.4% to 100%, and the application of SDF was better accepted in posterior teeth and in uncooperative children. ART had better aesthetic acceptance than HT. CONCLUSION: Application of SDF, Hall Technique and ART was well accepted by parents/caregivers. However, a gap remains in the literature regarding the acceptance of other procedures. Therefore, further studies in this area will contribute toward a better understanding of the opinion of parents/caregivers, and thus improve caries lesion management in children.


Assuntos
Cárie Dentária , Fluoretos , Compostos de Prata , Criança , Humanos , Cárie Dentária/tratamento farmacológico , Estudos Transversais , Dente Decíduo , Assistência Odontológica , Pais , Fluoretos Tópicos/uso terapêutico
11.
Appl Environ Microbiol ; 79(20): 6414-22, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23934501

RESUMO

A gene encoding a homolog to the cation diffusion facilitator protein DmeF from Cupriavidus metallidurans has been identified in the genome of Rhizobium leguminosarum UPM791. The R. leguminosarum dmeF gene is located downstream of an open reading frame (designated dmeR) encoding a protein homologous to the nickel- and cobalt-responsive transcriptional regulator RcnR from Escherichia coli. Analysis of gene expression showed that the R. leguminosarum dmeRF genes are organized as a transcriptional unit whose expression is strongly induced by nickel and cobalt ions, likely by alleviating the repressor activity of DmeR on dmeRF transcription. An R. leguminosarum dmeRF mutant strain displayed increased sensitivity to Co(II) and Ni(II), whereas no alterations of its resistance to Cd(II), Cu(II), or Zn(II) were observed. A decrease of symbiotic performance was observed when pea plants inoculated with an R. leguminosarum dmeRF deletion mutant strain were grown in the presence of high concentrations of nickel and cobalt. The same mutant induced significantly lower activity levels of NiFe hydrogenase in microaerobic cultures. These results indicate that the R. leguminosarum DmeRF system is a metal-responsive efflux mechanism acting as a key element for metal homeostasis in R. leguminosarum under free-living and symbiotic conditions. The presence of similar dmeRF gene clusters in other Rhizobiaceae suggests that the dmeRF system is a conserved mechanism for metal tolerance in legume endosymbiotic bacteria.


Assuntos
Cobalto/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Níquel/metabolismo , Óperon , Rhizobium leguminosarum/metabolismo , Fatores de Transcrição/metabolismo , Deleção de Genes , Perfilação da Expressão Gênica , Proteínas de Membrana Transportadoras/genética , Testes de Sensibilidade Microbiana , Pisum sativum/microbiologia , Rhizobium leguminosarum/efeitos dos fármacos , Rhizobium leguminosarum/genética , Rhizobium leguminosarum/fisiologia , Simbiose , Fatores de Transcrição/genética
12.
J Chem Phys ; 137(3): 034114, 2012 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-22830690

RESUMO

We developed a methodology to assess nuclear quantum effects in phase boundaries calculations that is based on the dynamical integration of Clausius-Clapeyron equation using path integral simulations. The technique employs non-equilibrium simulations that are very efficient. The approach was applied to the calculation of the melting line of Ne in an interval of pressures ranging from 1 to 3366 bar. Our results show a very good agreement with both experimental findings and results from previous calculations. The methodology can be applied to solid and liquid phases, without limitations regarding anharmonicities. The method allows the computation of coexistence lines for wide intervals of pressure and temperature using, in principle, a single simulation.

13.
Clin Nutr ESPEN ; 52: 138-143, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36513446

RESUMO

BACKGROUND & AIMS: Phase angle (PhA) has been used as an indicator of nutritional status. However, the significance of PhA reduction after bariatric surgery is less known. This study evaluated PhA and its relation with biochemical parameters and prognostic inflammatory and nutritional indices at a one-year follow-up of patients subjected to Roux-en-Y bypass (RYGB) or sleeve gastrectomy (SG). METHODS: Our final sample consisted of 25 patients subjected to RYGB and 11 to SG. Body mass index, fat-free mass, fat mass, PhA, serum transthyretin (TTR), albumin, C-reactive protein, alpha-1-acid glycoprotein, and prognostic inflammatory and nutritional indices were evaluated at four time points: before and approximately two, six, and 12 months after RYGB or SG. One-way repeated measures ANOVA or the Friedman test with Tukey's post hoc test was used depending on data distribution. The correlation between PhA and biochemical parameters and indices were evaluated using Spearman's or Pearson's correlation coefficients. RESULTS: Except for serum albumin, all parameters significantly decreased over time (p < 0.001). Only the RYGB group showed transthyretinTR values below reference ones. Prognostic indices significantly decreased in both groups (p < 0.001). We found a significant positive correlation of PhA with TTR in both RYGB (r = 0.475; p < 0.001) and SG (r = 0.457; p < 0.001). CONCLUSIONS: Data suggest that at a one-year follow-up after bariatric surgery, lower PhA values might indicate a concomitant loss of visceral protein and a worsening of protein nutritional status.


Assuntos
Derivação Gástrica , Obesidade Mórbida , Humanos , Obesidade Mórbida/cirurgia , Obesidade Mórbida/complicações , Estado Nutricional , Redução de Peso , Gastrectomia , Proteína C-Reativa
14.
Ann Oncol ; 22(5): 1215-1220, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21030383

RESUMO

BACKGROUND: The outcome of germ-cell tumors (GCTs) is a hallmark of good-quality cancer care. In the Eurocare-4 study, the mean 5-year survival for patients diagnosed from 1995 to 1999 was 95.5%. PATIENTS AND METHODS: We carried out a population-based retrospective chart review study of male patients diagnosed with GCT in 1999 and 2000 in southern Portugal (2 119 065 males). RESULTS: There were 87 GCTs-79 testicular, 2 retroperitoneal, 3 mediastinal, 2 of the central nervous system and 1 of the stomach. For the 81 patients with testicular or retroperitoneal primaries, 35 had stage I, 13 stage II and 30 stage III at presentation (3 unknown). Classification by International Germ Cell Consensus Classification Group criteria, 17 belonged to the poor prognosis group (mediastinal primary 3, liver metastases 11 and very elevated markers 3). With median follow-up of 89 months, the 5-year absolute overall survival was 80% (100% for stage I, 92% for stage II and 53% for stage III disease). CONCLUSIONS: While GCT incidence was similar to neighboring Spain, the 5-year overall survival was lower than that of other European countries. This may result from delays in diagnosis, suggested by high proportion of high-stage and large-burden disease, and poor adherence to recommended treatment algorithms.


Assuntos
Neoplasias Embrionárias de Células Germinativas/mortalidade , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Intervalo Livre de Doença , Humanos , Lactente , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Embrionárias de Células Germinativas/terapia , Portugal/epidemiologia , Estudos Retrospectivos , Neoplasias Testiculares/mortalidade , Neoplasias Testiculares/patologia , Neoplasias Testiculares/terapia , Adulto Jovem
15.
J Mol Model ; 27(7): 207, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34169387

RESUMO

The ground-state structural transition in small lithium clusters Lin (n = 4 - 6) is analyzed based on the many-body expansion of the interaction energy using the total energy calculated by the fixed-node diffusion Monte Carlo (FN-DMC) simulations. The results show that the transition from 2D to 3D structure occurs through an intricate competition of attractive and repulsive interaction energies. As the structure dimensionality increases from 2D to 3D, the electron-correlation contribution to the interaction energy in the isomer of the ground-state structure is always the largest.

16.
Vet Microbiol ; 246: 108726, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32605754

RESUMO

Porcine respirovirus 1 (PRV1) is an emerging virus in pigs that has been previously described in the USA and China. There are no reports of its presence in the rest of the world. The objective of this study was to determine the occurrence of PRV1 in Chile and to determine its phylogeny. Thus, we collected samples (oral fluids, nasal swabs, and lungs) from a swine influenza A virus (IAV) surveillance program, most of which belonged to pigs with respiratory disease. The samples were analyzed by RT-PCR, and the viral sequencing was obtained using RNA whole-genome sequencing approach. Maximum likelihood phylogeny was constructed with the available references. Thirty-one of 164 samples (18.9 %) were RT-PCR positive for PRV1: 62.5 % oral fluids, 19.0 % nasal swabs, and 8.6 % lungs. All 6 farms in this study had at least one positive sample, with 6-40 % of positive results per farm, which suggests that PRV1 is disseminated in Chilean swine farms. Twenty-one of 31 (677%) PRV1-positive samples were also positive for IAV, so the role of PRV1 as secondary pathogen in respiratory disease needs to be further evaluated. Near to complete genome of two PRV1s were obtained from two farms. The phylogenies, in general, showed low bootstrap support, except the concatenated genome and the L gene trees which showed clustering of the Chilean PRV1 with Asian sequences, suggesting a close genetic relationship. This is the first report of PRV1 in the Southern Hemisphere. Further studies are necessary to determine the genetic diversity of this virus in Chile.


Assuntos
Doenças Transmissíveis Emergentes/veterinária , Genoma Viral , Infecções por Orthomyxoviridae/veterinária , Filogenia , Respirovirus/genética , Doenças dos Suínos/virologia , Animais , Chile , Doenças Transmissíveis Emergentes/virologia , Fazendas , Respirovirus/isolamento & purificação , Análise de Sequência de DNA , Suínos , Sequenciamento Completo do Genoma
17.
Aust Vet J ; 102(1-2): 3-4, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38302109
18.
Transbound Emerg Dis ; 65(3): 696-710, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29250910

RESUMO

Foot-and-mouth disease (FMD) is, arguably, the animal disease with the most devastating global economic impact owing in part, to the severe trade restrictions imposed upon affected countries and regions. South Asia is one of the regions where widespread lineages of the FMDV virus (FMDV) have emerged. Here, we performed an integrative phylogenetic analysis of all FMDV serotypes (A, O and Asia-1) circulating in southern Asia, including viral sequences collected until 2013. Our results describe the occurrence of FMD caused by different serotypes and lineages, focusing in the cycles where a specific lineage predominates within a region for a protracted period and then are rapidly or progressively replaced by an emergent or re-emergent strain that is introduced from an adjacent region. Transmission between the two main regions in southern Asia (the Indian subcontinent and the region comprised by Afghanistan, Iran and Pakistan) has been limited. Results of time divergence estimation of lineages that currently circulate in this region indicate that the most recent common ancestor of endemic lineages are: 1992 [1989-1995] for lineage O/PanAsia; 1997 [1995-1999] for PanAsia2; 2001 [1998-2004] for O/Ind2001; 2001 [2000-2002] for A/Iran-05; 1990 [1988-1991] for A/G-18 (G-VII); 2003 [2000-2006] for Asia-1 Sindh08 and 2002 [1999-2004] for Asia-1 G-VIII. We estimated the mean of the overall substitution rate of the VP1 coding region (substitution/site/year) for serotype O (5.95 × 10-3 ), serotype A (1.19 × 10-2 ) and serotype Asia-1 (3.08 × 10-3 ). The potential factors driving the lineage turnover are discussed. Our results provide insights into the ecological and evolutionary factors driving the emergence of FMDV.


Assuntos
Vírus da Febre Aftosa/genética , Febre Aftosa/epidemiologia , Filogenia , Animais , Ásia/epidemiologia , Teorema de Bayes , Febre Aftosa/transmissão , Vírus da Febre Aftosa/classificação , Sorogrupo
19.
Transbound Emerg Dis ; 65(2): 534-546, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29034593

RESUMO

We report the laboratory analysis of 125 clinical samples from suspected cases of foot-and-mouth disease (FMD) in cattle and Asian buffalo collected in Pakistan between 2008 and 2012. Of these samples, 89 were found to contain viral RNA by rRT-PCR, of which 88 were also found to contain infectious FMD virus (FMDV) by virus isolation (VI), with strong correlation between these tests (κ = 0.96). Samples that were VI-positive were serotyped by antigen detection ELISA (Ag-ELISA) and VP1 sequence acquisition and analysis. Sequence data identified FMDV serotypes A (n = 13), O (n = 36) and Asia-1 (n = 41), including three samples from which both serotypes Asia-1 and O were detected. Serotype A viruses were classified within three different Iran-05 sublineages: HER-10, FAR-11 and ESF-10. All serotype Asia-1 were within Group VII (Sindh-08 lineage), in a genetic clade that differs from viruses isolated prior to 2010. All serotypes O were classified as PanAsia-2 within two different sublineages: ANT-10 and BAL-09. Using VP1 sequencing as the gold standard for serotype determination, the overall sensitivity of Ag-ELISA to correctly determine serotype was 74%, and serotype-specific sensitivity was 8% for serotype A, 88% for Asia-1 and 89% for O. Serotype-specific specificity was 100% for serotype A, 93% for Asia-1 and 94% for O. Interestingly, 12 of 13 serotype A viruses were not detected by Ag-ELISA. This study confirms earlier accounts of regional genetic diversity of FMDV in Pakistan and highlights the importance of continued validation of diagnostic tests for rapidly evolving pathogens such as FMDV.


Assuntos
Doenças dos Bovinos/virologia , Vírus da Febre Aftosa/isolamento & purificação , Febre Aftosa/virologia , Variação Genética , Animais , Antígenos Virais/imunologia , Búfalos , Bovinos , Testes Diagnósticos de Rotina , Ensaio de Imunoadsorção Enzimática/veterinária , Vírus da Febre Aftosa/genética , Paquistão , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Sensibilidade e Especificidade , Sorogrupo
20.
Transbound Emerg Dis ; 64(6): 1655-1660, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28921885

RESUMO

A novel equine arteritis virus (EAV) was isolated and sequenced from feral donkeys in Chile. Phylogenetic analysis indicates that the new virus and South African asinine strains diverged at least 100 years from equine EAV strains. The results indicate that asinine strains belonged to a different EAV genotype.


Assuntos
Infecções por Arterivirus/veterinária , Equartevirus/isolamento & purificação , Equidae , Animais , Infecções por Arterivirus/virologia , Chile , Equartevirus/classificação , Equartevirus/genética , Masculino , Filogenia , Reação em Cadeia da Polimerase/veterinária , Proteínas Virais/análise
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