Cytogenetics Research Papers - Academia.edu (original) (raw)

Colorectal carcinoma is the third most common cancer in the United States. Proper and standardized pathologic staging is vital for prognostic assessment and impacts therapeutic decisions. The Tumor Node Metastasis (TNM) staging system was... more

Colorectal carcinoma is the third most common cancer in the United States. Proper and standardized pathologic staging is vital for prognostic assessment and impacts therapeutic decisions. The Tumor Node Metastasis (TNM) staging system was developed by the American Joint Committee on Cancer (AJCC) to be a data-driven, evidence-based staging system providing an accurate prediction of outcome. The AJCC 7th edition (2010) included several changes clarifying some issues and leading to new controversies. We aim to address selected challenging issues in tumor T staging, neoadjuvant treatment effects in rectal cancer, and definition of lymph node vs tumor deposit. Serosal involvement in colorectal cancer is staged as T4, which is associated with decreased survival and may impact additional therapy decisions. Although careful sampling and sectioning are helpful, challenges remain in interpretation of tumor within 1 mm of serosal surface with a reaction. Elastic stain as a surrogate marker fo...

We report an unusual case of encephalo-entero-myopathy associated with the A8344G mutation in the tRNA(Lys) gene of mitochondrial DNA (mtDNA). This patient had mitochondrial myopathy, multiple lipomatosis, mild hearing loss, stroke-like... more

We report an unusual case of encephalo-entero-myopathy associated with the A8344G mutation in the tRNA(Lys) gene of mitochondrial DNA (mtDNA). This patient had mitochondrial myopathy, multiple lipomatosis, mild hearing loss, stroke-like episodes, and paralytic ileus, but she lacked the canonical clinical features of MERRF, myoclonus, epilepsy, or ataxia. We conducted genetic, biochemical, histochemical, and immunohistochemical studies in skeletal muscle, brain, intestine, and lipoma tissue. The mutation was abundant in all tissues, and cytochrome c oxidase (COX) activity was selectively decreased in brain and small intestine. COX deficiency was also documented histochemically and immunohistochemically in the small intestine, suggesting that mitochondrial dysfunction played a role in the pathogenesis of paralytic ileus. This case illustrates an unusual and dramatic clinical phenotype of the A8344G mutation, characterized by stroke-like episodes and acute ileus.

Urogenital birth defects are one of the common phenotypes observed in hereditary human disorders. In particular, limb malformations are often associated with urogenital developmental abnormalities, as the case for Hand-foot-genital... more

Urogenital birth defects are one of the common phenotypes observed in hereditary human disorders. In particular, limb malformations are often associated with urogenital developmental abnormalities, as the case for Hand-foot-genital syndrome displaying similar hypoplasia/agenesis of limbs and external genitalia. Split-hand/split-foot malformation (SHFM) is a syndromic limb disorder affecting the central rays of the autopod with median clefts of the hands and feet, missing central fingers and often fusion of the remaining ones. SHFM type 1 (SHFM1) is linked to genomic deletions or rearrangements, which includes the distal-less-related homeogenes DLX5 and DLX6 as well as DSS1. SHFM type 4 (SHFM4) is associated with mutations in p63, which encodes a p53-related transcription factor. To understand that SHFM is associated with urogenital birth defects, we performed gene expression analysis and gene knockout mouse model analyses. We show here that Dlx5, Dlx6, p63 and Bmp7, one of the p63 downstream candidate genes, are all expressed in the developing urethral plate (UP) and that targeted inactivation of these genes in the mouse results in UP defects leading to abnormal urethra formation. These results suggested that different set of transcription factors and growth factor genes play similar developmental functions during embryonic urethra formation. Human SHFM syndromes display multiple phenotypes with variations in addition to split hand foot limb phenotype. These results suggest that different genes associated with human SHFM could also be involved in the aetiogenesis of hypospadias pointing toward a common molecular origin of these congenital malformations.

The karyotype of spined loach Сobitis sp. for the first time found in Armenia in Aghstev River consists from 8 meta-, 14 submeta- and 28 subtelo/acrocentric chromosomes, NF=72. The comparative analysis of chromosomal sets of spined... more

The karyotype of spined loach Сobitis sp. for the first time found in Armenia in Aghstev River consists from 8 meta-, 14 submeta- and 28 subtelo/acrocentric chromosomes, NF=72. The comparative analysis of chromosomal sets of spined loaches from basins of Black and Caspian seas was shown that the karyotype of loach from Armenia is similar with the karyotypes of spined loaches of the second evolutionary line with 2n=50. The chromosomal set of Сobitis sp. from Armenia is more similar with Cobitis taenia satunini from Azerbaijan.

The only record of a Carollia brevicauda (Schinz, 1821) karyotype in Colombia to date was described from a single specimen collected from Leticia (department of Amazonas, Colombia). In this study, we offer a description of the karyotype... more

The only record of a Carollia brevicauda (Schinz, 1821) karyotype in Colombia to date was described from a single specimen collected from Leticia (department of Amazonas, Colombia). In this study, we offer a description of the karyotype of a female specimen of C. brevicauda, collected at 1,647 m in the locality of Chachagüi, in the Colombian Andes. The karyotype was obtained from bone marrow and conventional staining with Giemsa. We describe the chromosomal number, fundamental number and the karyotypic pattern. We compared the karyotype with others proposed for the species and several closely related species. This study increased the number of karyotypes reported for Colombian populations of C. brevicauda. The karyotype of C. brevicauda described in this paper agrees with karyotypes of other populations with 2n = 20 and FN = 36. The karyotypic pattern includes one sexual pair, two subtelocentrics pairs, two submetacentrics pairs and five metacentrics pairs. The pattern recorded herein is different to other reported for the species and the genus. The descriptions of variations in chromosomal morphology in C. brevicauda are incomplete, but it is possible that the different karyotypic patterns are indicators of polymorphism within the genus. Other studies are necessary to describe the yet undescribed karyotypes of C. manu and C. monohernandezi and to obtain additional evidence for the phylogenetic reconstructions of Carollia.

This study provides a genetic characterisation of two skink species, Trachylepis striata (Peters 1844) and Trachylepis wahlbergii (Peters 1869), by means of karyology and analysis of the 422-bp sequences of the 16S rRNA mitochondrial... more

This study provides a genetic characterisation of two skink species, Trachylepis striata (Peters 1844) and Trachylepis wahlbergii (Peters 1869), by means of karyology and analysis of the 422-bp sequences of the 16S rRNA mitochondrial gene. The two species have an identical karyotype, 2n= 32, NF= 64; no interspecific differences were found in the relative length of the chromosomes and their centromeric index. However, the karyotype of T. striata is very different from the one previously described for the same species.

Cytogenetic abnormalities of chromosome arm 9p occur frequently in children with acute lymphoblastic leukemia (ALL). We analyzed 201 such cases (11%) in 1,839 children with newly diagnosed ALL treated between 1989 and 1995 on... more

Cytogenetic abnormalities of chromosome arm 9p occur frequently in children with acute lymphoblastic leukemia (ALL). We analyzed 201 such cases (11%) in 1,839 children with newly diagnosed ALL treated between 1989 and 1995 on risk-adjusted protocols of the Children's Cancer Group (CCG). The majority of patients (131; 65%) with a 9p abnormality were classified as higher risk. Nearly all patients had complex karyotypes; most cases had deletions of 9p, add/der(9p), a dicentric involving chromosome arm 9p, and/or balanced translocations and inversions involving 9p. Event-free survival (EFS) estimates at 6 years for patients with and without a 9p aberration were 61% (standard deviation [SD] = 5%) and 76% (SD = 2%; P <.0001). In addition, patients with a 9p abnormality had an increased cumulative incidence of both marrow (P =.04) and central nervous system (P =.0001) relapses. Overall survival also was significantly worse for patients with an abnormal 9p (P <.0001). These effect...

The Resedaceae, containing 6 genera and ca. 85 species, are widely distributed in the Old World, with a major center of species diversity in the Mediterranean basin. Phylogenetic analyses of ITS and plastid trnL-trnF sequences of 66... more

The Resedaceae, containing 6 genera and ca. 85 species, are widely distributed in the Old World, with a major center of species diversity in the Mediterranean basin. Phylogenetic analyses of ITS and plastid trnL-trnF sequences of 66 species from all genera of the Resedaceae reveal (1) monophyly of the family, in congruence with preliminary phylogenetic studies; (2) molecular support for the traditional morphological subdivision of the Resedaceae into three tribes according to ovary and placentation types, and carpel number; (3) two monophyletic genera (Caylusea, Sesamoides), and one natural group (core Reseda), which includes the remaining four genera of the family (Ochradenus, Oligomeris, Randonia, Reseda); (4) a monophyletic origin for four of the six taxonomic sections recognized within Reseda (Leucoreseda, Luteola, Glaucoreseda, Phyteuma). Our results lead us to interpret an increment of the basic chromosome number in the family from x D 5 to x D 6 in at least two independent in...

In this study, we tested the ability of ethanolic extracts of mature leaves and rhizomes of Asplenium scolopendrium L. to synthesize Ag nanoparticles in vitro, and the genotoxic effects of the extracts on the root apexes of Allium cepa... more

In this study, we tested the ability of ethanolic extracts of mature leaves and rhizomes of Asplenium scolopendrium L. to synthesize Ag nanoparticles in vitro, and the genotoxic effects of the extracts on the root apexes of Allium cepa were assessed. The roots with a length of 0.5–1 cm were exposed to the action of extracts before and after the synthesis of Ag nanoparticles, for 6, 12 and 24 h. The chemical composition of the extract was evaluated by means of spectroscopic analytical techniques. After the synthesis of the Ag nanoparticles a slight increase was noticed in the antioxidant activity of the extracts. The mito-stimulating effect of the extracts obtained from the leaves, and respectively the mito-inhibiting effect of the extracts from the rhizome, was augmented by the synthesis of Ag nanoparticles, which was associated with an increase in variability and frequency of chromosome aberrations. To our knowledge, this is the first study to have shown the ability of ethanolic extracts of mature leaves and rhizomes of A. scolopendrium L. to phytosynthesize Ag nanoparticles in vitro, and has revealed the comparative chemical composition and the cytogenotoxic potential of the extracts. The present study highlights the need for continuous evaluation of plant resources, and is intended to help in accumulate knowledge for a natural therapy that meets the health care needs.

It is a seminar submitted at biology department as the introduction lecture to the cytogenetic application workshop organized by Dr. Bushra M.A.Mohammed.