Effects of trichostatin A on FHIT and WWOX genes expression, cell growth inhibition and apoptosis induction in hepatocellular carcinoma WCH 17 cell line

Previously, we evaluated the effect of trichostatin A (TSA) on the expression of DNA methyltransferase 1 (DNMT1) in Hepatocellular Carcinoma (HCC). Fragile histidine triad (FHIT) and WW domain-containing oxidoreductase (WWOX) are two of the most common down-regulated genes in many cancers located on chromosome 3p14.2 and 16q23.3-24.1 respectively. The aim of the current study was to assess the effect of TSA on these genes expression, cell growth, and apoptosis in HCC WCH 17 cell. The cells were seeded and treated with TSA at different times. Then, MTT assay, flow cytometry, and qRT-PCR were achieved to determine viability, apoptosis and gene expression respectively. Cell growth was significantly inhibited, 92 to 36% after 24 h, 86 to 28% after 48 h, and 78 to 24% after 72 h. The results of flow cytometry confirmed that TSA increased apoptosis compared to the control group, the apoptosis percentage increased to 12%, 16%, and 18% in comparison to control groups (2%). Significant up-regulation of the genes was observed in all treated groups. We concluded that re-expression of silenced WWOX and FHIT genes could be achieved by TSA resulting in cell growth inhibition and apoptosis induction in WCH 17 cell.

Geographic separation of domestic and wild strains of Toxoplasma gondii in French Guiana correlates with a monomorphic version of chromosome1a.

BACKGROUND: Previous studies have stressed the genetic divergence and high pathogenicity of strains of T. gondii from French Guiana. Although strains from coastal, human adapted environments (so called anthropized) resemble those found in other regions of the Caribbean, strains collected from inland jungle environment are genetically quite diverse. To better understand the composition of these distinct strain types, we undertook a more in depth analysis of T. gondii strains from French Guiana including profiling of chromosome 1a (Chr1a), which is often shared as a single monomorphic haplotype among lineages that are otherwise genetically distinct. METHODOLOGY/PRINCIPAL FINDINGS: Comparison of intron sequences from selectively neutral genes indicated that anthropized strains were most closely related to clonal type III strains from North America, although wider RFLP analysis revealed that they are natural hybrids. In contrast, strains isolated from the jungle were genetically very diverse. Remarkably, nearly all anthropized strains contained the monomorphic version of Chr1a while wild stains were extremely divergent. The presence of the monomorphic Chr1a strongly correlated with greater transmission in domestic cats, although there were several exceptions, indicating that other factors also contribute. Anthropized strains also varied in their virulence in laboratory mice, and this pattern could not be explained by the simple combination of previously identified virulence factors, indicating that other genetic determinants influence pathogenicity. CONCLUSIONS/SIGNIFICANCE: Our studies underscore the marked genetic separation of anthropized and wild strains of T. gondii in French Guiana and provide additional evidence that the presence of Chr1a is associated with successful expansion of widely different lineages within diverse geographic areas. The predominance of Chr1a among strains in the anthropized environment suggests that it may confer an advantage for transmission in this environment, and thus potentially contribute to the spread of pathogenecity determinants.

Detecção de locos de características quantitativas nos cromossomos 1, 2, 3, 12, 14, 15 e X de suínos: características de desempenho / Detection of quantitative trait loci on chromosomes 1, 2, 3, 12, 14, 15, X in pigs: performance characteristics

Mapeou-se quantitative trait loci (QTL) associados a características de desempenho nos cromossomos 1, 2, 3, 12, 14, 15 e X de suínos pertencentes a uma população F2, formada a partir do cruzamento entre dois machos da raça naturalizada brasileira Piau e 18 fêmeas comerciais (Landrace x Large White x Pietrain). O mapa genético de ligação da população foi construído após a genotipagem dos animais para 35 marcadores microssatélites. As estimativas do conteúdo de informação polimórfica indicaram que os marcadores microssatélites foram adequados para as análises de QTL. Os dados foram analisados pelo mapeamento por intervalo usando-se o programa GridQTL. Encontraram-se seis QTL, sendo que o QTL genômico para idade ao abate atingiu a significância de 5% de probabilidade. As informações dos QTL detectados neste estudo são úteis para identificar genes que podem ser usados em conjunto com os métodos convencionais de seleção, aumentar a acurácia deles e prover uma compreensão dos fenótipos produtivos de suínos.

The accomplishment of the present study had the objective of mapping Quantitative Trait Loci (QTL) related to performance traits in a F2 pig population developed by mating two Brazilian Piau breed sires with 18 dams from a commercial line (Landrace × Large White × Pietrain). The linkage map for this population was constructed after genotyping the animals for 35 microsatellite markers. Estimates of polymorphic information content indicated that the microsatellite markers were appropriate for QTL analyses. The genotypes were analyzed by interval mapping using the GridQTL program. A total of six QTL were found, of which the QTL for slaughter age (days) was significant at the 5% genome-wise level. The information of the significant QTL detected in this study is useful for future fine-mapping studies for the identification of genes. Such information can be used together with traditional methods in breeding programs or even for a better understanding of the phenotypes of swine production.

Detecção de locos de características quantitativas nos cromossomos 1, 2, 3, 12, 14, 15 e X de suínos: características de desempenho / Detection of quantitative trait loci on chromosomes 1, 2, 3, 12, 14, 15, X in pigs: performance characteristics

Mapeou-se quantitative trait loci (QTL) associados a características de desempenho nos cromossomos 1, 2, 3, 12, 14, 15 e X de suínos pertencentes a uma população F2, formada a partir do cruzamento entre dois machos da raça naturalizada brasileira Piau e 18 fêmeas comerciais (Landrace x Large White x Pietrain). O mapa genético de ligação da população foi construído após a genotipagem dos animais para 35 marcadores microssatélites. As estimativas do conteúdo de informação polimórfica indicaram que os marcadores microssatélites foram adequados para as análises de QTL. Os dados foram analisados pelo mapeamento por intervalo usando-se o programa GridQTL. Encontraram-se seis QTL, sendo que o QTL genômico para idade ao abate atingiu a significância de 5% de probabilidade. As informações dos QTL detectados neste estudo são úteis para identificar genes que podem ser usados em conjunto com os métodos convencionais de seleção, aumentar a acurácia deles e prover uma compreensão dos fenótipos produtivos de suínos.(AU)

The accomplishment of the present study had the objective of mapping Quantitative Trait Loci (QTL) related to performance traits in a F2 pig population developed by mating two Brazilian Piau breed sires with 18 dams from a commercial line (Landrace × Large White × Pietrain). The linkage map for this population was constructed after genotyping the animals for 35 microsatellite markers. Estimates of polymorphic information content indicated that the microsatellite markers were appropriate for QTL analyses. The genotypes were analyzed by interval mapping using the GridQTL program. A total of six QTL were found, of which the QTL for slaughter age (days) was significant at the 5% genome-wise level. The information of the significant QTL detected in this study is useful for future fine-mapping studies for the identification of genes. Such information can be used together with traditional methods in breeding programs or even for a better understanding of the phenotypes of swine production.(AU)

Genetics of neotropical fish: from chromosomes to populations.

The Neotropical freshwater fish fauna is very rich--according to the most recent catalogue 71 families and 4,475 species have been described. However, only a small amount of general information is available on the composition of Neotropical marine fishes. In Brazil, 1,298 marine species have been recorded. General analysis of available cytogenetic and population genetic data clearly indicates research has been mainly concentrated on freshwater fishes. Thus, today, cytogenetic information is available for 475 species of Characiformes, 318 species of Siluriformes, 48 species of Gymnotiformes, 199 freshwater species that do not belong to the superorder Ostariophysi, and only 109 species of marine fishes. For the species studied, only about 6% have sex chromosomes and about 5% have supernumerary or B chromosomes. A review of the cytogenetic studies shows that these data have provided valuable information about the relationships between fish groups, the occurrence of cryptic species and species complexes, the mechanism of sex determination and sex chromosome evolution, the distribution of nucleolus organizer regions, the existence supernumerary chromosomes, and the relationship between polyploidy and evolution. In relation to populations in Neotropical marine waters, the studies have shown the presence of cryptic species, which has important implications for fishery management. Different levels of genetic structuring can be found among Neotropical freshwater migratory fish species. This raises important implications for fish population genetic diversity and consequently its sustainable utilization in inland fisheries and aquaculture, specifically for conservation of ichthyo-diversity and survival.

Alterações cromossômicas em síndrome mielodisplásica / Chromosomal abnormalities in myelodysplastic syndrome

O estudo das alterações cromossômicas em síndrome mielodisplásica (SMD) é de extrema importância porque auxilia no diagnóstico, prognóstico, classificação, acompanhamento evolutivo, escolha terapêutica e melhor entendimento da biologia da doença. As alterações cromossômicas são observadas em 30 por cento a 50 por cento dos casos de SMD primária, ao diagnóstico, e entre 80 por cento e 90 por cento das secundárias. Os cromossomos 5, 7, 8, 11, 13, 17, 20, 21 e X são os mais freqüentemente envolvidos. As alterações cromossômicas são variáveis independentes de valor prognóstico e correlacionam-se com o curso clínico da doença e com a transformação. Destacam-se como indicativos de bom prognóstico: cariótipo normal, nulissomia Y, del(5q), del(12p), del(11q) e del(20q) isoladas; como de prognóstico intermediário: trissomia 8, rearranjos envolvendo 3q21q26, translocações 11q, del(17p), trissomia 18 e trissomia 19; e como de prognóstico desfavorável: cariótipo complexo, monossomia 7, del(7q) e i(17q). Em relação à classificação, a Organização Mundial da Saúde tornou obrigatória a análise do cariótipo para a completa avaliação da SMD recém diagnosticada e definiu a síndrome 5q- como entidade específica. No tocante ao acompanhamento, alterações podem ser detectadas evolutivamente, definindo agressividade ou transformação da doença. Atualmente alguns tratamentos já são delineados com base nas alterações cromossômicas. Não se sabe se as alterações cromossômicas detectadas em SMD são eventos iniciais que levam ao desenvolvimento da doença (causa) ou se são apenas fenômenos secundários (conseqüência). De qualquer forma, elas apontam que, em nível molecular, há uma série de aspectos ainda por serem entendidos.

The study of chromosomal abnormalities in myelodysplastic syndrome (MDS) is important for diagnosis, prognosis, classification, follow-up, therapeutic option and for a better understanding of the biology of the disease. Chromosomal aberrations are observed in 30 percent to 50 percent of MDS cases at diagnosis, and from 80 percent to 90 percent of secondary MDS. Chromosomes 5, 7, 8, 11, 13, 17, 20, 21 and X are the most frequently involved. Chromosomal aberrations have an independent prognosis value and relate with clinical course and transformation. As good prognosis abnormalities figure: normal karyotype, nulisomy Y, isolated del(5q), del(12p), del(11q) and del(20q); as intermediate prognosis are: trisomy 8, 3q21q26 rearrangements, translocations 11q, del(17p), trisomy 18 and trisomy 19; and as unfavorable prognosis: complex karyotype, monosomy 7, del(7q) and i(17q). Referring to classification, the World Health Organization established karyotype analysis as mandatory for MDS diagnosis and defined 5q- Syndrome as a specific entity. In respect to follow-up, abnormalities can be detected subsequently delineating aggressiveness or transformation of the disease. Nowadays some therapeutic options are underlined by chromosomal abnormalities. It is not known if the chromosomal aberrations detected in MDS are initial events that lead to the development of the disease (cause) or are secondary phenomena (consequences). Anyway, they point out that at molecular level there is a series of aspects not well understood yet.

Sympatric occurrence of three cytotypes and four morphological types of B chromosomes of Astyanax scabripinnis (Pisces, Characiformes) in the River Ivaí Basin, state of Paraná, Brazil.

Chromosomes of Astyanax scabripinnis from the Tatupeba stream, Ivaí Basin (state of Paraná, Brazil), were analyzed. Astyanax scabripinnis population presents 3 different diploid numbers (2n = 46, 48 and 50) and B chromosomes in each cytotype. Eighty per cent of the females among individuals of cytotype I (2n = 50) has a metacentric B macrochromosome, whereas three different types of B chromosomes were identified in individuals of cytotype II (2n = 48). Cytotype III (2n = 46) showed two B chromosomes of different morphologic types (metacentric macrochromosomes and acrocentric) in all specimens and cells analyzed. Constitutive heterochromatin pattern for the three cytotypes showed weak markings in centromeric regions and conspicuous blocks in the telomere regions of ST and A chromosomes. Whereas C-banding showed that B chromosomes were totally or partially heterochromatic, a discussion on their behavior and origin was also undertaken.

Karyotype description of Pomacea patula catemacensis (Caenogastropoda, Ampullariidae), with an assessment of the taxonomic status of Pomacea patula

Mitotic chromosomes of the freshwater snail Pomacea patula catemacensis (Baker 1922) were analyzed on gill tissue of specimens from the type locality (Lake Catemaco, Mexico). The diploid number of chromosomes is 2n = 26, including nine metacentric and four submetacentric pairs, therefore, the fundamental number is FN = 52. No sex chromosomes could be identified. The same chromosome number and morphology were already reported for P. flagellata, i.e., the other species of the genus living in Mexico. The basic haploid number for family Ampullariidae was reported to be n = 14 in the literaure; so, its reduction to n = 13 is probably an apomorphy of the Mexican Pomacea snails. Lanistes bolteni, from Egypt, also shows n = 13, but its karyotype is much more asymmetrical, and seems to have evolved independently from P. flagellata and P. patula catemacencis. The nominotypical subspecies, P. patula patula (Reeve 1856), is a poorly known taxon, whose original locality is unknown. A taxonomical account is presented here, and a Mexican origin postulated as the most parsimonious hypothesis.

Karyotype description of Pomacea patula catemacensis (Caenogastropoda, Ampullariidae), with an assessment of the taxonomic status of Pomacea patula

Mitotic chromosomes of the freshwater snail Pomacea patula catemacensis (Baker 1922) were analyzed on gill tissue of specimens from the type locality (Lake Catemaco, Mexico). The diploid number of chromosomes is 2n = 26, including nine metacentric and four submetacentric pairs, therefore, the fundamental number is FN = 52. No sex chromosomes could be identified. The same chromosome number and morphology were already reported for P. flagellata, i.e., the other species of the genus living in Mexico. The basic haploid number for family Ampullariidae was reported to be n = 14 in the literaure; so, its reduction to n = 13 is probably an apomorphy of the Mexican Pomacea snails. Lanistes bolteni, from Egypt, also shows n = 13, but its karyotype is much more asymmetrical, and seems to have evolved independently from P. flagellata and P. patula catemacencis. The nominotypical subspecies, P. patula patula (Reeve 1856), is a poorly known taxon, whose original locality is unknown. A taxonomical account is presented here, and a Mexican origin postulated as the most parsimonious hypothesis. (AU)

Karyotype description of Pomacea patula catemacensis (Caenogastropoda, Ampullariidae), with an assessment of the taxonomic status of Pomacea patula.

Mitotic chromosomes of the freshwater snail Pomacea patula catemacensis (Baker 1922) were analyzed on gill tissue of specimens from the type locality (Lake Catemaco, Mexico). The diploid number of chromosomes is 2n = 26, including nine metacentric and four submetacentric pairs; therefore, the fundamental number is FN = 52, No sex chromosomes could be identified. The same chromosome number and morphology were already reported for P. flagellata, i.e., the other species of the genus living in Mexico. The basic haploid number for family Ampullariidae was reported to be n = 14 in the literature; so, its reduction to n = 13 is probably an apomorphy of the Mexican Pomacea snails. Lanistes bolteni, from Egypt, also shows n = 13, but its karyotype is much more asymmetrical, and seems to have evolved independently from P. flagellata and P. patula catemacensis. The nominotypical subspecies, P. patula patula (Reeve 1856), is a poorly known taxon, whose original locality is unknown. A taxonomical account is presented here, and a Mexican origin postulated as the most parsimonious hypothesis.

[Karyotypic comparison of five species of Lutzomyia (diptera: psychodidae) of the series townsendi and the verrucarum group in Colombia]. / Comparación cariotípica de cinco especies de Lutzomyia (diptera: psychodidae) de la serie townsendi grupo verrucarum en Colombia.

Cytogenetic characteristics were established for five native species of phlebotomine sand flies (Lutzomyia, series townsendi, verrucarum group): Lutzomyia longiflocosa, Lutzomyia townsendi, Lutzomyia spinicrassa, Lutzomyia torvida and Lutzomyia youngi. Karyotypes and chromosomal morphometry were compared. Using the squash technique, brain tissues from late 4th instar larvae provided the necessary mitotic chromosomes. Chromosomal measurements were made on the following chromosomal characteristics: short arm, long arm, arm ratio, total length, relative length, centromeric index and relative length average of chromosomes. Chromosomes were classified according to their morphometry and position of the centromere. The taxonomic distance was calculated, and the relationships among the species displayed in a phenogram. All five species possessed four pairs of chromosomes as diploid number (2N = 8). None of the karyotypes indicated presence of heteromorphic chromosomes. Statistical analysis of the morphometric data showed highly significant differences among the chromosomes pairs of the five species. However, the total length of the genome was very similar, with the exception of L. youngi. In conclusion, these closely related species were distinguishable at cytological level.

Diagnóstico prenatal II: importancia de los marcadores ecográficos en el diagnóstico prenatal de cromosomopatías / Prenatal diagnosis II: importance of the echosonographic markers in the prenatal diagnosis of chromosomophathies

En la Unidad de Genética Médica de la Universidad del Zulia (UGM-LUZ), desde enero 1993 hasta el presente, se viene desarrollando un Programa de Diagnóstico Prenatal (P-DxPN) donde se determinan los Factores de Riesgo Genético (FRG) de las parejas que solicitan asesoramiento genético prenatal y se realizan distintos procedimientos de DxPN que permiten el diagnóstico intrauterino de diferentes defectos congénitos. Uno de los procedimientos de DxPN utilizados es la Ecografía Fetal (EF). La EF es una técnica no invasiva de DxPN que permite el diagnóstico de gran parte de los síndromes dismorfogenéticos y en la actualidad, a través de la búsqueda de características específicas anormales fetales, pueden ser sospechadas algunas cromosomopatías. A estos hallazgos se les denomina "Marcadores Ecográficos de Cromosomopatías" (MEC). En un período de 3 años (enero 93-diciembre 96) han sido atendidos en el P-DxPN 321 gestantes y realizado 312 EF, resultando anormales 22 estudios, 17 con malformaciones fetales aisladas y 5 con MED que sugirieron el diagnóstico de alguna cromosomopatía específica. Sólo 1 feto con una cromosomopatía estructural (46,XX,21q-) no pudo sospecharse por EF. Los objetivos de este trabajo son: 1) Reportar 5 pacientes con marcadores ecográficos sugestivos de anormalidades citogenéticas y 2) Demostrar la utilidad de la EF en el DxPN de cromosomopatías. Estos reportes, nos hacen concluir que, la EF y la búsqueda de MEC, deben ser ofrecidas sistemáticamente a aquellas madres sin riesgos genéticos reconocibles, ya que son ellas las que representan el grupo mayoritario en cuanto a paridad y por ende, un número relativamente mayor de productos con defectos congénitos, de etiología cromosómica o no, los cuales en su mayoría pudieran detectarse por este método y permitir la selección de aquellas gestantes en quien se justificaría la práctica de métodos de DxPN invasivos

Diagnóstico y manejo de pacientes con anormalidades de la diferenciación sexual: experiencia de la Unidad de Genética Médica de la Universidad del Zulia, Maracaibo, Venezuela / Diagnosis and management of patients with abnormalities of sexual diferentiation: experience of the Medical Genetic Unit, University of Zulia, Maracaibo, Venezuela

Las anormalidades de la Diferenciación Sexual (ADS) representan un conjunto de enfermedades, heterogéneas tanto en su etiopatogenia como en sus manifestaciones clínicas. Con la finalidad de caracterizar y analizar los aspectos epidemiológicos, clínicos, endocrinos y genéticos de los pacientes con ADS que consultaron a UGM-LUZ en el período 1971-1996, se evaluaron todas las familias que tuvieron al menos un afectado, estableciendose criterios diagnósticos estrictos para cada entidad. A cada paciente se les practicó estudio citogenético en sangre periférica, determinaciones hormonales, evaluaciones radioecodiagnósticas y estudios anatomohistopatológicos según cada caso en particular. De 391 familias 489 pacientes consultaron por presentar ADS, lo que representa el 5,4 por ciento del total de los pacientes que consultaron a UGM-LUZ en el período señalado. Se detectaron 214 (50 por ciento) pacientes con diagnóstico definitivo de ADS al cumplir los criterios de inclusión establecidos, distribuidos de la siguiente manera: 139 con Anomalías de los cromosomas sexuales; 36 con hiperplasia adrenal congénita; 21 con síndrome de insensibilidad androgénica completa; 14 con disgenesia gonadal mixta y 4 con hermafroditismo verdadero. Se diagnósticaron 183 pacientes (42,7 por ciento) con pseudohermafroditismo masculino y 17 (3,9 por ciento) con pseudohermafroditismo femenino, al no llenar los criterios diagnósticos establecidos. 15 (3,4 por ciento) pacientes presentaron ADS asociada a un cuadro polimalformativo. Las ADS representan una causa importante de morbilidad en UGM-LUZ. Estas, por ser entidades nosológicas complejas necesitan de la integración multidisciplinaria del equipo de salud

Chromosome diversity of the genus Aotus from Colombia.

Description of six Colombian karyomorphs is completed through an extensive cytogenetic characterization of 35 Aotus (owl monkeys) specimens. The description of a new karyomorph for Colombian Aotus by chromosome on Q, G, R, and C, sequential banding is included. Pairs of karyomorphs 2 and 3 and 6 and 9 with 2n of 54, and 50, respectively, as well as karyomorphs 7 and 8 with 46 and 58 chromosomes were strongly suspected to represent different species on the grounds of large karyotypic differences. A proposal for a chromosome nomenclature of Aotus karyomorphs that aims to clarify Aotus taxonomy is presented which achieves a precise correspondence of different banding patterns, based on Q, G, R, and C sequential banding and chromosome measurements. Although our contribution is not a universal nomenclature system, unique criteria for chromosome denomination within Aotus karyomorphs are established. Previous systems of chromosome nomenclature have not successfully addressed the nomenclature of chromosomes of the same karyotype.