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1.
Braz J Biol ; 82: e262248, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35703634

RESUMO

Satellites associated begomoviruses are the most diverse group of plant viruses in tropical and subtropical regions. In Pakistan, during field surveys in 2019-2020, Sonchus palustris (a weed plant) was observed showing begomovirus symptoms i.e., vein yellowing and mosaic patterns on leaves. Rolling circle amplification from total isolated DNA of symptomatic leaves was performed to amplify circular viral genomes. Subsequent cloning and sequencing showed that a new strain of Alternanthera yellow vein virus (AlYVV) is associated with vein yellowing disease of S. palustris. The identity percentage analysis through BLAST search and SDT analysis showed that the new strain is 94-98% identical to AlYVV isolates reported from Pakistan, India and China. In phylogenetic tree, it clustered with AlYVV-[PK:E prostrata:15-KX710155], AlYVV-[PK:E prostrata:13]-KX906697] and AlYVV-[PK:E prostrata:11]-KX906694] previously reported from Pakistan. There was no detectable level of betasatellite or any other satellite molecule in the samples studied here. Phylogenetic analysis of Rep and CP genes of AlYVV with corresponding genes of closely related viruses circulating in Southeast Asia showed intra-specific recombination involving both complementary and virion sense region of virus. Relaxed clock and Bayesian Skyline Plot analysis based on CP gene sequences indicated slight higher substitution rates (4.75 x 10-3 substitutions/nucleotide/year). In the Indian subcontinent satellite-associated monopartite begomoviruses predominately infect crops and non-crop plants. But AlYVV is found infecting mostly non-crop plants independent of satellite molecules. We hypothesize here that AlYVV evolved as a true monopartite begomovirus in the Indian sub-continent and could be a great threat to introduced crops under suitable conditions. Such studies are crucial to understand probable future epidemics of begomoviruses in the region.


Assuntos
Begomovirus , Sonchus , Teorema de Bayes , Begomovirus/genética , DNA Viral/genética , Paquistão , Filogenia , Doenças das Plantas , Análise de Sequência de DNA , Sonchus/genética
2.
Braz. j. biol ; 82: e262248, 2022. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1384040

RESUMO

Satellites associated begomoviruses are the most diverse group of plant viruses in tropical and subtropical regions. In Pakistan, during field surveys in 2019-2020, Sonchus palustris (a weed plant) was observed showing begomovirus symptoms i.e., vein yellowing and mosaic patterns on leaves. Rolling circle amplification from total isolated DNA of symptomatic leaves was performed to amplify circular viral genomes. Subsequent cloning and sequencing showed that a new strain of Alternanthera yellow vein virus (AlYVV) is associated with vein yellowing disease of S. palustris. The identity percentage analysis through BLAST search and SDT analysis showed that the new strain is 94-98% identical to AlYVV isolates reported from Pakistan, India and China. In phylogenetic tree, it clustered with AlYVV-[PK:E prostrata:15-KX710155], AlYVV-[PK:E prostrata:13]-KX906697] and AlYVV-[PK:E prostrata:11]-KX906694] previously reported from Pakistan. There was no detectable level of betasatellite or any other satellite molecule in the samples studied here. Phylogenetic analysis of Rep and CP genes of AlYVV with corresponding genes of closely related viruses circulating in Southeast Asia showed intra-specific recombination involving both complementary and virion sense region of virus. Relaxed clock and Bayesian Skyline Plot analysis based on CP gene sequences indicated slight higher substitution rates (4.75 x 10-3 substitutions/nucleotide/year). In the Indian subcontinent satellite-associated monopartite begomoviruses predominately infect crops and non-crop plants. But AlYVV is found infecting mostly non-crop plants independent of satellite molecules. We hypothesize here that AlYVV evolved as a true monopartite begomovirus in the Indian sub-continent and could be a great threat to introduced crops under suitable conditions. Such studies are crucial to understand probable future epidemics of begomoviruses in the region.


Os begomovírus associados aos satélites são o grupo mais diversificado de vírus de plantas encontrado em regiões tropicais e subtropicais. No Paquistão, durante pesquisas de campo entre 2019 e 2020, a espécie Sonchus palustris L. (uma planta daninha) foi observada apresentando sintomas de begomovírus, ou seja, amarelecimento das veias e padrões de mosaico nas folhas. A Amplificação em Círculo Rolante (ACR) a partir de DNA isolado total de folhas sintomáticas foi realizada para amplificar genomas virais circulares. A clonagem e sequenciamento subsequentes mostraram que uma nova cepa de Alternanthera yellow vein virus (AlYVV) está associada à doença do amarelecimento das veias de S. palustris. A análise da porcentagem de identidade por meio de pesquisa BLAST e análise SDT mostrou que a nova cepa é 94-98% idêntica aos isolados de AlYVV relatados no Paquistão, Índia e China. Na árvore filogenética, essa cepa se agrupou com AlYVV-[PK:E prostrata:15-KX710155], AlYVV-[PK:E prostrata:13]-KX906697] e AlYVV-[PK:E prostrata:11]-KX906694] relatada anteriormente de Paquistão. Não houve nível detectável de betassatélite ou qualquer outra molécula satélite nas amostras estudadas aqui. A análise filogenética de genes Rep e CP de AlYVV com genes correspondentes de vírus intimamente relacionados que estão circulando no Sudeste Asiático mostrou recombinação intraespecífica envolvendo a região complementar e de sentido viral do vírus. Relógio molecular relaxado e análise de Bayesian Skyline Plot (BSP) com base nas sequências do gene CP indicaram taxas de substituição ligeiramente mais altas (4,75 x 10-3 substituições/nucleotídeo/ano). No subcontinente indiano, os begomovírus monopartidos associados aos satélites infectam predominantemente culturas e plantas não cultivadas. Mas o AlYVV é encontrado infectando principalmente plantas não cultivadas, independentemente de moléculas satélites. Desenvolveu-se a hipótese de que o AlYVV evoluiu como um verdadeiro begomovírus monopartido no subcontinente indiano e pode ser uma grande ameaça às culturas introduzidas em condições adequadas. Tais estudos são cruciais para entender prováveis e ​​futuras epidemias de begomovírus na região.


Assuntos
Animais , Paquistão , Filogenia , Sonchus/parasitologia , Begomovirus
3.
Phys Rev Lett ; 127(1): 013401, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34270294

RESUMO

Dipole-dipole interactions lead to frequency shifts that are expected to limit the performance of next-generation atomic clocks. In this work, we compute dipolar frequency shifts accounting for the intrinsic atomic multilevel structure in standard Ramsey spectroscopy. When interrogating the transitions featuring the smallest Clebsch-Gordan coefficients, we find that a simplified two-level treatment becomes inappropriate, even in the presence of large Zeeman shifts. For these cases, we show a net suppression of dipolar frequency shifts and the emergence of dominant nonclassical effects for experimentally relevant parameters. Our findings are pertinent to current generations of optical lattice and optical tweezer clocks, opening a way to further increase their current accuracy, and thus their potential to probe fundamental and many-body physics.

4.
Braz J Med Biol Res ; 51(3): e6853, 2018 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-29340523

RESUMO

Glutathione synthetase deficiency (GSSD) is a rare inborn error of glutathione metabolism with autosomal recessive inheritance. The severe form of the disease is characterized by acute metabolic acidosis, usually present in the neonatal period with hemolytic anemia and progressive encephalopathy. A case of a male newborn infant who had severe metabolic acidosis with high anion gap, hemolytic anemia, and hyperbilirubinemia is reported. A high level of 5-oxoproline was detected in his urine and a diagnosis of generalized GSSD was made. DNA sequence analysis revealed the infant to be compound heterozygous with two mutations, c.738dupG in exon 8 of GSS gene resulting in p.S247fs and a repetitive sequence in exon 3 of GSS gene. Treatment after diagnosis of GSSD included supplementation with antioxidants and oral sodium hydrogen bicarbonate. However, he maintained a variable degree of metabolic acidosis and succumbed shortly after his parents requested discontinuation of therapy because of dismal prognosis and medical futility when he was 18 days old.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/genética , Glutationa Sintase/deficiência , Mutação , Acidose/etiologia , Erros Inatos do Metabolismo dos Aminoácidos/metabolismo , Ácido Glutâmico/análise , Glutationa Sintase/genética , Glutationa Sintase/metabolismo , Humanos , Recém-Nascido , Masculino , Piroglutamato Hidrolase/deficiência , Piroglutamato Hidrolase/genética , Análise de Sequência de DNA/métodos
5.
Braz. j. med. biol. res ; 51(3): e6853, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889048

RESUMO

Glutathione synthetase deficiency (GSSD) is a rare inborn error of glutathione metabolism with autosomal recessive inheritance. The severe form of the disease is characterized by acute metabolic acidosis, usually present in the neonatal period with hemolytic anemia and progressive encephalopathy. A case of a male newborn infant who had severe metabolic acidosis with high anion gap, hemolytic anemia, and hyperbilirubinemia is reported. A high level of 5-oxoproline was detected in his urine and a diagnosis of generalized GSSD was made. DNA sequence analysis revealed the infant to be compound heterozygous with two mutations, c.738dupG in exon 8 of GSS gene resulting in p.S247fs and a repetitive sequence in exon 3 of GSS gene. Treatment after diagnosis of GSSD included supplementation with antioxidants and oral sodium hydrogen bicarbonate. However, he maintained a variable degree of metabolic acidosis and succumbed shortly after his parents requested discontinuation of therapy because of dismal prognosis and medical futility when he was 18 days old.


Assuntos
Humanos , Masculino , Recém-Nascido , Erros Inatos do Metabolismo dos Aminoácidos/genética , Glutationa Sintase/deficiência , Mutação , Acidose/etiologia , Erros Inatos do Metabolismo dos Aminoácidos/metabolismo , Ácido Glutâmico/análise , Glutationa Sintase/genética , Glutationa Sintase/metabolismo , Piroglutamato Hidrolase/deficiência , Piroglutamato Hidrolase/genética , Análise de Sequência de DNA/métodos
6.
Braz J Med Biol Res ; 50(7): e6071, 2017 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-28678921

RESUMO

Cystic echinococcosis (CE) is an anthropozoonotic disease with worldwide distribution and is caused by the cestode Echinococcus granulosus. Anaphylactic shock induced by CE rupture is a serious complication especially in patients with hydatid infections, as the resulting leakage of fluid contains highly toxic endogenous antigen. We aimed to isolate and identify the antigens of specific IgE and IgG1 (sIgE and sIgG1) in E. granulosus cyst fluid (EgCF). Crude antigen for EgCF was prepared from E. granulosus-infected sheep liver. Antigens were separated and identified by one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (1D SDS-PAGE), two-dimensional gel electrophoresis (2-DE), and immunoblotting. Results of 1D SDS-PAGE and immunoblotting showed that 40.5 kDa protein was the major antigen of sIgE, and 35.5 kDa protein was the major antigen of sIgG1 in EgCF. Results of 2-DE and immunoblotting showed that main antigens of sIgE in EgCF were four proteins with pI values ranging from 6.5 to 9.0 and a molecular weight of 40.5 kDa. Main antigens of sIgG1 in EgCF were five proteins with pI values ranging from 6.5 to 9.0 and a molecular weight of 35.5 kDa. The antigens identified for sIgE and sIgG1 can provide critical insights into cellular and molecular mechanisms underlying anaphylactic shock induced by CE.


Assuntos
Anafilaxia/parasitologia , Antígenos de Helmintos/imunologia , Equinococose/complicações , Echinococcus granulosus/imunologia , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Adolescente , Adulto , Anafilaxia/imunologia , Animais , Antígenos de Helmintos/sangue , Estudos de Casos e Controles , Criança , Equinococose/imunologia , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Immunoblotting , Masculino , Adulto Jovem
7.
Braz. j. med. biol. res ; 50(7): e6071, 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-951705

RESUMO

Cystic echinococcosis (CE) is an anthropozoonotic disease with worldwide distribution and is caused by the cestode Echinococcus granulosus. Anaphylactic shock induced by CE rupture is a serious complication especially in patients with hydatid infections, as the resulting leakage of fluid contains highly toxic endogenous antigen. We aimed to isolate and identify the antigens of specific IgE and IgG1 (sIgE and sIgG1) in E. granulosus cyst fluid (EgCF). Crude antigen for EgCF was prepared from E. granulosus-infected sheep liver. Antigens were separated and identified by one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (1D SDS-PAGE), two-dimensional gel electrophoresis (2-DE), and immunoblotting. Results of 1D SDS-PAGE and immunoblotting showed that 40.5 kDa protein was the major antigen of sIgE, and 35.5 kDa protein was the major antigen of sIgG1 in EgCF. Results of 2-DE and immunoblotting showed that main antigens of sIgE in EgCF were four proteins with pI values ranging from 6.5 to 9.0 and a molecular weight of 40.5 kDa. Main antigens of sIgG1 in EgCF were five proteins with pI values ranging from 6.5 to 9.0 and a molecular weight of 35.5 kDa. The antigens identified for sIgE and sIgG1 can provide critical insights into cellular and molecular mechanisms underlying anaphylactic shock induced by CE.


Assuntos
Humanos , Animais , Masculino , Feminino , Criança , Adolescente , Adulto , Adulto Jovem , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Echinococcus granulosus/imunologia , Equinococose/complicações , Anafilaxia/parasitologia , Antígenos de Helmintos/imunologia , Ensaio de Imunoadsorção Enzimática , Immunoblotting , Estudos de Casos e Controles , Equinococose/imunologia , Eletroforese em Gel de Poliacrilamida , Anafilaxia/imunologia , Antígenos de Helmintos/sangue
8.
Genet Mol Res ; 15(2)2016 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-27173339

RESUMO

MicroRNA-154 (miR-154) is dysregulated in some human malignancies and is correlated with tumor progression. However, its expression and function in non-small cell lung cancer (NSCLC) remain unclear. Therefore, we explored the effects of miR-154 on NSCLC tumorigenesis and development. Using quantitative reverse transcription-polymerase chain reaction, we detected miR-154 expression in NSCLC cell lines and primary tumor tissues. The association between miR-154 expression and clinicopathological factors was investigated, and the effects of miR-154 on the biological behavior of NSCLC cells were examined. Ultimately, the potential regulatory effect of miR-154 on high-mobility group A2 protein (HMGA2) expression was confirmed. miR-154 was significantly downregulated in NSCLC cell lines and clinical specimens. Reduced miR-154 expression was significantly associated with lymph node metastasis, advanced TNM stage, and shorter overall survival. Multivariate regression analysis confirmed that downregulation of miR-154 was an independent unfavorable prognostic factor for patients with NSCLC. Overexpression of miR-154 inhibited NSCLC cell proliferation, invasion, and migration, and promoted cell apoptosis in vitro. Furthermore, a luciferase reporter assay identified HMGA2 as a direct target of miR-154. Our findings indicate that miR-154 may act as a tumor suppressor in NSCLC and would serve as a novel therapeutic agent for miR-based therapy.

9.
Zhonghua Er Ke Za Zhi ; 54(5): 375-8, 2016 May.
Artigo em Chinês | MEDLINE | ID: mdl-27143081

RESUMO

OBJECTIVE: To analyze the clinical characteristics, outcome and diagnosis of two cases of imported children Zika virus infection in China. METHOD: A retrospective analysis was performed on clinical characteristics, treatment and outcome of two cases of imported children with Zika virus infection in February 2016 in Enping People's Hospital of Guangdong. RESULT: Two cases of children with imported Zika virus infection resided in an affected area of Venezuela, 8-year-old girl and her 6 year-old brother. The main findings on physical examination included the following manifestations: fever, rash, and conjunctivitis. The rash was first limited to the abdomen, but extended to the torso, neck and face, and faded after 3-4 d. The total number of white blood cells was not high and liver function was normal. The diagnosis of two cases of Zika virus infection was confirmed by the expert group of Guangdong Provincial Center for Disease Control and Prevention, according to the epidemiological history, clinical manifestations and Zika virus nucleic acid detection results.Treatment of Zika virus infection involves supportive care. Two Zika virus infection children had a relatively benign outcome. CONCLUSION: At present, Zika virus infection in children is an imported disease in China. No specific therapy is available for this disease. Information on long-term outcomes among infants and children with Zika virus disease is limited, routine pediatric care is advised for these infants and children.


Assuntos
Infecção por Zika virus/diagnóstico , Zika virus/isolamento & purificação , Criança , China , Exantema , Feminino , Febre , Humanos , Masculino , Estudos Retrospectivos , Venezuela
10.
Clin Transl Oncol ; 18(3): 322-30, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26260915

RESUMO

OBJECTIVE: Metastatic breast cancer (MBC) remains the main cause of cancer-related death, and the clinical significance and prognostic role of circulating tumor cells (CTCs) in metastatic breast cancer are still controversial. Here, we conducted a meta-analysis to clarify the correlation between CTCs and the clinicopathological features and prognosis of MBC. METHODS: We performed a comprehensive search of Pubmed and the ISI Web of Science through December 2014. Only articles that focused on MBC patients and detected CTCs using the CellSearch system were included. The associations between CTCs and survival rate and clinicopathological parameters, including molecular pattern, metastatic region and treatment response, were evaluated. RESULTS: This meta-analysis included 24 studies (3701 MBC patients), 13 prospective studies and 11 retrospective studies. We found that CTCs were more frequently detected with HER2 + primary tumors (pooled RR = 0.73, 95 % CI = 0.63-0.84). Additionally, higher CTC numbers indicated a worse treatment response (RR = 0.56, 95 % CI = 0.40-0.79), poorer PFS (RR = 0.64, 95 % CI = 0.56-0.73) and poorer OS (RR = 0.69, 95 % CI = 0.64-0.75) in MBC patients. CONCLUSION: Based on these results, we propose that HER2 positivity could be a significant risk factor for the presence of CTCs. Additionally, CTCs have a significant prognostic value for MBC patients. Therefore, CTCs should be continually monitored to guide the treatment of MBC patients, especially those with HER2 + primary tumors.


Assuntos
Neoplasias da Mama/patologia , Células Neoplásicas Circulantes/patologia , Neoplasias da Mama/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Prognóstico , Receptor ErbB-2/biossíntese
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