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1.
Genet Mol Biol ; 42(2): 436-444, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31259358

RESUMEN

Two allopatric populations of Brazilian diploid and tetraploid Odontophrynus americanus species complex, both from São Paulo state, had their blood hemoglobin biochemically analyzed. In addition, these specimens were cytogenetically characterized. Biochemical characterization of hemoglobin expression showed a distinct banding pattern between the allopatric specimens. Besides this, two distinct phenotypes, not linked to ploidy, sex, or age, were observed in adult animals of both populations. Phenotype A exhibits dark-colored body with small papillae, ogival-shaped jaw with reduced interpupillary distance and shorter hind limbs. Phenotype B shows yellowish-colored body with larger papillae, arch-shaped jaw with broader interpupillary distance and longer hind limbs. Intermediate phenotypes were also found. Considering the geographical isolation of both populations, differences in chromosomal secondary constrictions and distinct hemoglobins banding patterns, these data indicate that 2n and 4n populations represent cryptic species in the O. americanus species complex. The observed phenotypic diversity can be interpreted as population genetic variability. Eventually future data may indicate a probable beginning of speciation in these Brazilian frogs. Such inter- and intrapopulational differentiation/speciation process indicates that O. americanus species complex taxonomy deserves further evaluation by genomics and metabarcoding communities, also considering the pattern of hemoglobin expression, in South American frogs.

2.
Genet. Mol. Biol. ; 42(2): 436-444, 2019.
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib16072

RESUMEN

Two allopatric populations of Brazilian diploid and tetraploid Odontophrynus americanus species complex, both from São Paulo state, had their blood hemoglobin biochemically analyzed. In addition, these specimens were cytogenetically characterized. Biochemical characterization of hemoglobin expression showed a distinct banding pattern between the allopatric specimens. Besides this, two distinct phenotypes, not linked to ploidy, sex, or age, were observed in adult animals of both populations. Phenotype A exhibits dark-colored body with small papillae, ogival-shaped jaw with reduced interpupillary distance and shorter hind limbs. Phenotype B shows yellowish-colored body with larger papillae, arch-shaped jaw with broader interpupillary distance and longer hind limbs. Intermediate phenotypes were also found. Considering the geographical isolation of both populations, differences in chromosomal secondary constrictions and distinct hemoglobins banding patterns, these data indicate that 2n and 4n populations represent cryptic species in the O. americanus species complex. The observed phenotypic diversity can be interpreted as population genetic variability. Eventually future data may indicate a probable beginning of speciation in these Brazilian frogs. Such inter- and intrapopulational differentiation/speciation process indicates that O. americanus species complex taxonomy deserves further evaluation by genomics and metabarcoding communities, also considering the pattern of hemoglobin expression, in South American frogs.

3.
Genet Mol Biol, v. 42, n. 2, p. 436-444, jun. 2019
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-2784

RESUMEN

Two allopatric populations of Brazilian diploid and tetraploid Odontophrynus americanus species complex, both from São Paulo state, had their blood hemoglobin biochemically analyzed. In addition, these specimens were cytogenetically characterized. Biochemical characterization of hemoglobin expression showed a distinct banding pattern between the allopatric specimens. Besides this, two distinct phenotypes, not linked to ploidy, sex, or age, were observed in adult animals of both populations. Phenotype A exhibits dark-colored body with small papillae, ogival-shaped jaw with reduced interpupillary distance and shorter hind limbs. Phenotype B shows yellowish-colored body with larger papillae, arch-shaped jaw with broader interpupillary distance and longer hind limbs. Intermediate phenotypes were also found. Considering the geographical isolation of both populations, differences in chromosomal secondary constrictions and distinct hemoglobins banding patterns, these data indicate that 2n and 4n populations represent cryptic species in the O. americanus species complex. The observed phenotypic diversity can be interpreted as population genetic variability. Eventually future data may indicate a probable beginning of speciation in these Brazilian frogs. Such inter- and intrapopulational differentiation/speciation process indicates that O. americanus species complex taxonomy deserves further evaluation by genomics and metabarcoding communities, also considering the pattern of hemoglobin expression, in South American frogs.

4.
Genet. mol. biol ; 40(1): 1-21, Jan.-Mar. 2017. tab, graf
Artículo en Inglés | LILACS | ID: biblio-892372

RESUMEN

Abstract In the last decades, a group of viruses has received great attention due to its relationship with cancer development and its wide distribution throughout the vertebrates: the papillomaviruses. In this article, we aim to review some of the most relevant reports concerning the use of bovines as an experimental model for studies related to papillomaviruses. Moreover, the obtained data contributes to the development of strategies against the clinical consequences of bovine papillomaviruses (BPV) that have led to drastic hazards to the herds. To overcome the problem, the vaccines that we have been developing involve recombinant DNA technology, aiming at prophylactic and therapeutic procedures. It is important to point out that these strategies can be used as models for innovative procedures against HPV, as this virus is the main causal agent of cervical cancer, the second most fatal cancer in women.

5.
Genet Mol Biol ; 40(1): 1-21, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28212457

RESUMEN

In the last decades, a group of viruses has received great attention due to its relationship with cancer development and its wide distribution throughout the vertebrates: the papillomaviruses. In this article, we aim to review some of the most relevant reports concerning the use of bovines as an experimental model for studies related to papillomaviruses. Moreover, the obtained data contributes to the development of strategies against the clinical consequences of bovine papillomaviruses (BPV) that have led to drastic hazards to the herds. To overcome the problem, the vaccines that we have been developing involve recombinant DNA technology, aiming at prophylactic and therapeutic procedures. It is important to point out that these strategies can be used as models for innovative procedures against HPV, as this virus is the main causal agent of cervical cancer, the second most fatal cancer in women.

6.
Vaccine ; 35(12): 1590-1593, 2017 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-28222997

RESUMEN

Bovine papillomatosis is an infectious disease that is caused by bovine papillomavirus (BPV), which results in important economic losses. However, no BPV vaccines or effective treatment methods are commercially available to date. Moreover, the absence of papillomavirus replication in vitro makes the use of recombinant protein a promising candidate for vaccine formulations. Hence, we developed an integrated study on the L1 capsid protein of BPV-1, obtained from a bacterial expression system, regarding its purification, biosafety, thermostability and immunogenicity. The results indicated an absence of genotoxicity of the purified recombinant L1 protein, ß-sheet prevalence of secondary structure folding, protein stability under high temperatures as well as the presence of capsomeres and VLPs. In addition, preliminary experimental vaccination of calves showed the production of specific antibodies against BPV-1 L1.


Asunto(s)
Papillomavirus Bovino 1/inmunología , Proteínas de la Cápside/inmunología , Enfermedades de los Bovinos/prevención & control , Infecciones por Papillomavirus/veterinaria , Vacunas contra Papillomavirus/inmunología , Animales , Anticuerpos Antivirales/sangre , Papillomavirus Bovino 1/genética , Proteínas de la Cápside/química , Proteínas de la Cápside/genética , Bovinos , Infecciones por Papillomavirus/prevención & control , Vacunas contra Papillomavirus/administración & dosificación , Vacunas contra Papillomavirus/genética , Conformación Proteica , Pliegue de Proteína , Multimerización de Proteína , Estabilidad Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/genética , Vacunas Sintéticas/inmunología , Vacunas de Partículas Similares a Virus/química , Vacunas de Partículas Similares a Virus/genética , Vacunas de Partículas Similares a Virus/inmunología
7.
Genet. Mol. Biol. ; 40(1): 1-21, 2017.
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib15517

RESUMEN

In the last decades, a group of viruses has received great attention due to its relationship with cancer development and its wide distribution throughout the vertebrates: the papillomaviruses. In this article, we aim to review some of the most relevant reports concerning the use of bovines as an experimental model for studies related to papillomaviruses. Moreover, the obtained data contributes to the development of strategies against the clinical consequences of bovine papillomaviruses (BPV) that have led to drastic hazards to the herds. To overcome the problem, the vaccines that we have been developing involve recombinant DNA technology, aiming at prophylactic and therapeutic procedures. It is important to point out that these strategies can be used as models for innovative procedures against HPV, as this virus is the main causal agent of cervical cancer, the second most fatal cancer in women.

8.
Vaccine ; 35(12): 1590-1593, 2017.
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib15393

RESUMEN

Bovine papillomatosis is an infectious disease that is caused by bovine papillomavirus (BPV), which results in important economic losses. However, no BPV vaccines or effective treatment methods are commercially available to date. Moreover, the absence of papillomavirus replication in vitro makes the use of recombinant protein a promising candidate for vaccine formulations. Hence, we developed an integrated study on the L1 capsid protein of BPV-1, obtained from a bacterial expression system, regarding its purification, biosafety, thermostability and immunogenicity. The results indicated an absence of genotoxicity of the purified recombinant L1 protein, beta-sheet prevalence of secondary structure folding, protein stability under high temperatures as well as the presence of capsomeres and VLPs. In addition, preliminary experimental vaccination of calves showed the production of specific antibodies against BPV-1 L1.

9.
Biomed Pharmacother ; 82: 449-58, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27470384

RESUMEN

Cancer is a group of highly complex and heterogeneous diseases with several causes. According to the stochastic model, cancer initiates from mutation in somatic cells, leading to genomic instability and cell transformation. This canonical pathway of carcinogenesis is related to the discovery of important mechanisms that regulate cancer initiation. However, there are few studies describing genetic and metabolic alterations that deregulate transformed cells, resulting in epithelial-mesenchymal transition (EMT) and its most dramatic consequence, the metastasis. This review summarizes the main genetics and metabolic changes induced by reactive oxygen species (ROS) that lead to EMT.


Asunto(s)
Carcinogénesis/genética , Carcinogénesis/metabolismo , Animales , Metabolismo Energético , Transición Epitelial-Mesenquimal , Humanos , Metástasis de la Neoplasia , Especies Reactivas de Oxígeno/metabolismo , Sistemas de Mensajero Secundario
10.
Biomed. Pharmacother ; 82: p. 449-458, 2016.
Artículo | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib14540

RESUMEN

Cancer is a group of highly complex and heterogeneous diseases with several causes. According to the stochastic model, cancer initiates from mutation in somatic cells, leading to genomic instability and cell transformation. This canonical pathway of carcinogenesis is related to the discovery of important mechanisms that regulate cancer initiation. However, there are few studies describing genetic and metabolic alterations that deregulate transformed cells, resulting in epithelial-mesenchymal transition (EMT) and its most dramatic consequence, the metastasis. This review summarizes the main genetics and metabolic changes induced by reactive oxygen species (ROS) that lead to EMT. (C) 2016 Elsevier Masson SAS. All rights reserved.


Asunto(s)
Oncología Médica , Genética
11.
Biomed Res Int ; 2015: 806361, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26783529

RESUMEN

Bovine papillomavirus (BPV) is considered a useful model to study HPV oncogenic process. BPV interacts with the host chromatin, resulting in DNA damage, which is attributed to E5, E6, and E7 viral oncoproteins activity. However, the oncogenic mechanisms of BPV E6 oncoprotein per se remain unknown. This study aimed to evaluate the mutagenic potential of Bos taurus papillomavirus type 1 (BPV-1) E6 recombinant oncoprotein by the cytokinesis-block micronucleus assay (CBMNA) and comet assay (CA). Peripheral blood samples of five calves were collected. Samples were subjected to molecular diagnosis, which did not reveal presence of BPV sequences. Samples were treated with 1 µg/mL of BPV-1 E6 oncoprotein and 50 µg/mL of cyclophosphamide (positive control). Negative controls were not submitted to any treatment. The samples were submitted to the CBMNA and CA. The results showed that BPV E6 oncoprotein induces clastogenesis per se, which is indicative of genomic instability. These results allowed better understanding the mechanism of cancer promotion associated with the BPV E6 oncoprotein and revealed that this oncoprotein can induce carcinogenesis per se. E6 recombinant oncoprotein has been suggested as a possible vaccine candidate. Results pointed out that BPV E6 recombinant oncoprotein modifications are required to use it as vaccine.


Asunto(s)
Papillomavirus Bovino 1/genética , Proteínas Oncogénicas Virales/genética , Infecciones por Papillomavirus/genética , Proteínas Recombinantes/genética , Animales , Papillomavirus Bovino 1/patogenicidad , Carcinogénesis/genética , Bovinos , Línea Celular , Ciclofosfamida/administración & dosificación , Inestabilidad Genómica/efectos de los fármacos , Humanos , Proteínas Oncogénicas Virales/administración & dosificación , Papillomaviridae/genética , Papillomaviridae/patogenicidad , Infecciones por Papillomavirus/virología , Proteínas Recombinantes/administración & dosificación
15.
Diagn Cytopathol ; 41(9): 785-92, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23630112

RESUMEN

Herein, we evaluated cervical samples from normal tissue or HPV-infected tissue, to determine if the relative nuclear/cytoplasmic ratio (NA/CA) and the presence of nonclassical cytological criteria are a novel cytological criterion for the diagnosis of HPV. Significantly, larger NA/CA ratios were found for the HPV-ATYPIA+ and HPV+ATYPIA+ groups compared with HPV-ATYPIA- group, regardless of collection method. For the samples collected with a spatula, only three samples from the HPV-ATIPIA- group showed four or more nonclassical parameters (i.e., were positive), while a larger number of the samples in the HPV-ATYPIA+, HPV+ATYPIA-, and HPV+ATYPIA+ groups were positive (13, 4, and 13 samples, respectively). Among those collected with a brush, no sample showed four or more nonclassical criteria in the HPV-ATYPIA- group, while a number of samples were positive in the HPV-ATYPIA+, HPV+ATYPIA-, and HPV+ATYPIA+ groups (4, 3, and 4 samples, respectively). HPV infection was associated with significant morphometrical changes; no increase in the NA/CA ratio was found in the HPV+ATYPIA- samples, compared with the HPV-ATIPIA- samples collected with either a spatula or a brush. In conclusion, by including nonclassical cytological criteria into the patient diagnosis, we were able to reduce the number of false negative and false positive HPV diagnoses made using conventional cytology alone.


Asunto(s)
Cuello del Útero/patología , Cuello del Útero/virología , Citodiagnóstico/métodos , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/diagnóstico , Infecciones por Papillomavirus/virología , Frotis Vaginal , Adolescente , Adulto , Anciano , Núcleo Celular/patología , Femenino , Humanos , Persona de Mediana Edad , Adulto Joven
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