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2.
J BUON ; 18(2): 535-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23818374

RESUMO

We performed prospective sequential cytogenetic studies in 76 patients with myelodysplastic syndromes (MDS) followed up to 82 months. Their karyotypes were followed routinely, regardless of clinical status. The incidence of evolutive karyotypes was similar in patients with a normal karyotype at referral and in patients with clonal abnormalities at diagnosis (24.5 and 26.1%, respectively). We did not find association between karyotype evolution and leukemic transformation or reduced survival, since the majority of secondary cytogenetic changes in evolutive karyotypes of our patients were aberrations with good or intermediate prognosis. Therefore, we concluded that only particular cytogenetic events are related to disease progression, while others represent secondary changes of little biologic and prognostic significance.


Assuntos
Cariotipagem , Leucemia/genética , Síndromes Mielodisplásicas/genética , Evolução Clonal , Progressão da Doença , Predisposição Genética para Doença , Humanos , Leucemia/mortalidade , Leucemia/patologia , Síndromes Mielodisplásicas/mortalidade , Síndromes Mielodisplásicas/patologia , Fenótipo , Prognóstico , Estudos Prospectivos , Fatores de Risco
3.
IEEE Trans Syst Man Cybern B Cybern ; 42(4): 966-79, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22736651

RESUMO

Automatic facial expression recognition has been an active topic in computer science for over two decades, in particular facial action coding system action unit (AU) detection and classification of a number of discrete emotion states from facial expressive imagery. Standardization and comparability have received some attention; for instance, there exist a number of commonly used facial expression databases. However, lack of a commonly accepted evaluation protocol and, typically, lack of sufficient details needed to reproduce the reported individual results make it difficult to compare systems. This, in turn, hinders the progress of the field. A periodical challenge in facial expression recognition would allow such a comparison on a level playing field. It would provide an insight on how far the field has come and would allow researchers to identify new goals, challenges, and targets. This paper presents a meta-analysis of the first such challenge in automatic recognition of facial expressions, held during the IEEE conference on Face and Gesture Recognition 2011. It details the challenge data, evaluation protocol, and the results attained in two subchallenges: AU detection and classification of facial expression imagery in terms of a number of discrete emotion categories. We also summarize the lessons learned and reflect on the future of the field of facial expression recognition in general and on possible future challenges in particular.

6.
Oncogene ; 25(32): 4413-20, 2006 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-16547498

RESUMO

Aneuploidy is a fundamental principle of many cancer cells and is mostly related to defects in mitotic segregation of chromosomes. Many solid tumors as well as some preneoplastic lesions have been shown to contain polyploid chromosome numbers. The exact mechanisms behind whole-genome duplications are not known but have been linked to compromised mitotic checkpoint genes. We now report that the telomere checkpoint plays a key role for polyploidy in colon cancer cells. Telomerase suppression by a dominant-negative mutant of hTERT and consecutive telomere dysfunction in wild-type HCT116 colon cancer cells resulted in only minor stable chromosomal alterations. However, higher ploidy levels with up to 350 chromosomes were found when the cell-cycle checkpoint proteins p53 or p21 were absent. These findings indicate that telomere dysfunction in the absence of cell-cycle control may explain the high frequency of alterations in chromosome numbers found in many solid tumors.


Assuntos
Segregação de Cromossomos/genética , Mitose/genética , Neoplasias/genética , Neoplasias/patologia , Telômero/patologia , Proteína Supressora de Tumor p53/deficiência , Proteína Supressora de Tumor p53/genética , Células HCT116 , Humanos , Proteína Supressora de Tumor p53/fisiologia
7.
Leuk Lymphoma ; 45(9): 1873-9, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15223649

RESUMO

The clinical, cytogenetic, and immunophenotypic features in 12 adult patients with acute panmyelosis with myelofibrosis (APMF; ICD-0-3: 9931/3; C42.1) are reported (median age: 57 years; f/m = 1.4). The white cell count (WBC) was normal in 3 patients; 9 had leucopenia. The median hemoglobin value was 64.5 g/l, and median platelet count 12 x 10(9)/l. Bone marrow biopsy showed a hypercellular marrow in 10/12 patients with a significant infiltration of pathological blasts (range: 30 - 60%). All the cases had marked reticulin fibrosis. Immunophenotyping of bone marrow blast cells showed the expression of early (CD34) and lineage-unspecified antigens (HLA-DR) in 6/7, and 7/7 patients, respectively. "Early" myeloid antigens (CD13, CD33) were seen in 6/7 and 4/6 patients respectively. Monocyte antigen (CD14) was expressed in 3/7 patients. Megakaryocyte antigen (CD61) and erythroid cell antigen (GpA) were each expressed in only 1 patient. Two patients had expression of CD34, HLA-DR and "early" myeloid antigens by their bone marrow blast cells and 1 of these also had a co-expression of the antigens from a differentiated monocytic cell proliferation (lysozyme+, CD68+). Nonspecific chromosomal aberrations were recorded in 8/10 patients. The median survival was 2 months. These findings suggest an immature myeloid phenotype of blast cells in APMF. In 6/9 patients a leukemic cell differentiation into monocytic, megakaryocytic or erythroid lineage was also demonstrated.


Assuntos
Mielofibrose Primária/genética , Mielofibrose Primária/patologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Imunofenotipagem , Cariotipagem , Masculino , Pessoa de Meia-Idade , Mielofibrose Primária/sangue , Mielofibrose Primária/imunologia , Taxa de Sobrevida , Resultado do Tratamento
8.
EMBO J ; 20(24): 6958-68, 2001 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-11742973

RESUMO

Telomerase, the ribonucleoprotein enzyme maintaining the telomeres of eukaryotic chromosomes, is active in most human cancers and in germline cells but, with few exceptions, not in normal human somatic tissues. Telomere maintenance is essential to the replicative potential of malignant cells and the inhibition of telomerase can lead to telomere shortening and cessation of unrestrained proliferation. We describe novel chemical compounds which selectively inhibit telomerase in vitro and in vivo. Treatment of cancer cells with these inhibitors leads to progressive telomere shortening, with no acute cytotoxicity, but a proliferation arrest after a characteristic lag period with hallmarks of senescence, including morphological, mitotic and chromosomal aberrations and altered patterns of gene expression. Telomerase inhibition and telomere shortening also result in a marked reduction of the tumorigenic potential of drug-treated tumour cells in a mouse xenograft model. This model was also used to demonstrate in vivo efficacy with no adverse side effects and uncomplicated oral administration of the inhibitor. These findings indicate that potent and selective, non-nucleosidic telomerase inhibitors can be designed as novel cancer treatment modalities.


Assuntos
Divisão Celular/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Telomerase/antagonistas & inibidores , Perfilação da Expressão Gênica , Humanos , Neoplasias/genética , Neoplasias/patologia , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Telômero , Células Tumorais Cultivadas
9.
Med Oncol ; 17(4): 307-13, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11114710

RESUMO

Patients with acute promyelocytic leukemia (APL) show other chromosome aberrations in addition to t(15;17) but their influence on the clinical outcome is still unclear. We have cytogeneticaly analyzed 43 APL patients with t(15;17)(q22;q21), treated with all-trans-retinoic acid (ATRA) according to the recommendations of the European APL 91 Group. Additional chromosome aberrations were observed in 14/43 patients (33%) studied at initial diagnosis. These patients were designed as 'complex' karyotype group and were compared to patients with t(15;17) asa sole cytogenetic abnormality ('simple' karyotype group). The 'complex' group had significantly lower platelet count and fibrinogen level and fewer cases without significant DIC at diagnosis than the 'simple' group. Comparison of 'simple' and 'complex' groups showed significant difference in complete remission rate (76% vs 35.7%, P = 0.0148) and early death rate (24% vs 64.3%, P = 0.0141). Survival analysis showed that the presence of additional chromosome abnormalities and significant DIC had an adverse effects on prognosis (P = 0.036 and P = 0.041, respectively), independent on other prognostic factors. These data indicate more aggressive biological nature of leukemic cells in patients with additional chromosome aberrations. Supplementary therapeutic strategies may be required for this subgroup of APL patients.


Assuntos
Cromossomos Humanos Par 15/genética , Cromossomos Humanos Par 17/genética , Leucemia Promielocítica Aguda/tratamento farmacológico , Leucemia Promielocítica Aguda/genética , Translocação Genética , Adolescente , Adulto , Idoso , Antineoplásicos/uso terapêutico , Feminino , Seguimentos , Humanos , Cariotipagem , Masculino , Pessoa de Meia-Idade , Prognóstico , Análise de Sobrevida , Tretinoína/uso terapêutico
10.
Am J Clin Pathol ; 114(1): 29-34, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10884796

RESUMO

From a cohort of 220 adults with newly diagnosed acute myeloid leukemia (AML), 8 (3.6%) exhibited a rare variant of aberrant membrane phenotype. It was characterized with typical myeloid morphologic and cytochemical patterns and absence of myeloid associated antigens (CD13, CD33, CD14, glycophorin A, CD61). According to the French-American-British criteria, disease in 5 patients was classified as M1 and in 3 patients as M2. CD34, CD38, HLA-DR, and CD45 were strongly expressed in 4 of 5, 3 of 3, 8 of 8, and 3 of 3 analyzed cases, respectively. CD7 antigen was strongly expressed in 4 of 6 patients. Except for predominance of male sex and high frequency of CD7 antigen expression, no other remarkable clinical or biologic characteristics were noted. Detected variant of AML with the unusual membrane phenotype (CD34+, HLA-DR-positive, CD38+, CD45+, CD7+) might represent an example of extreme asynchrony in sequences of morphologic and immunologic maturation or abnormal epitope expression on leukemic cell membrane molecules CD13 and CD33. Although the clinical significance of this AML variant is unclear, the existence of such cases demonstrates the continued need for simultaneous cytochemical and immunologic studies in the evaluation of acute leukemias.


Assuntos
Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Antígenos CD13/análise , Leucemia Mieloide/imunologia , Doença Aguda , Adolescente , Adulto , Idoso , Antineoplásicos/uso terapêutico , Medula Óssea/patologia , Citogenética , Feminino , Humanos , Imunofenotipagem , Leucemia Mieloide/tratamento farmacológico , Leucemia Mieloide/genética , Leucemia Mieloide/patologia , Masculino , Pessoa de Meia-Idade , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico , Análise de Sobrevida
11.
Cancer Genet Cytogenet ; 111(1): 77-80, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10326595

RESUMO

A 71-year-old woman presented with malaise, skin bruising, epistaxis, and gingival bleeding of recent and prompt onset. There was no adenopathy. The liver and spleen were not enlarged. Bone marrow aspirate showed a polymorphous infiltration with lymphocytes (22%), typical Marschalko plasma cells (16%), plasmacytoid lymphocytes (29%), lymphoblasts (8%), and immunoblasts (13%). The immunoblasts morphologically resembled lymphosarcoma cells with a frequent "clover-leaf" appearance. An IgM paraprotein concentration in serum was 38.5 g/L. The bone marrow histopathology confirmed the presence of heterogenous cell infiltration, with 30% of the population being comprised of lymphoblasts and immunoblasts. In order to differentiate a polymorphous variant of Waldenström macroglobulinemia (WM) from the more common small cell lymphocytic lymphoma (SLL) in anaplastic metamorphosis, flow cytometric studies were performed on marrow specimens. A typically bright surface IgM (lambda) was demonstrated with a less bright CD38. Further immunophenotype was HLA-DR+, CD19+, CD20+ and CD10-, CD22-, T-Ag- and kappa light chain- expression. This corroborated the diagnosis of an extremely rare, polymorphous variant of WM. The marrow cytogenetics disclosed 50% (10/20) pathologic metaphases 48,X,dup(X)(p21p22),der(2), +5,del(6)(q11q21), +12,inv(16)(p13q22), del(17) (p12), and 50% normal metaphases. The patient was treated with a LOPP protocol. She failed to respond and died 5 months after the diagnosis with myocardial and renal insufficiency complicating a pronounced pancytopenia in the peripheral blood.


Assuntos
Aberrações Cromossômicas , Macroglobulinemia de Waldenstrom/genética , Idoso , Feminino , Humanos , Imunofenotipagem , Cariotipagem , Macroglobulinemia de Waldenstrom/imunologia , Macroglobulinemia de Waldenstrom/patologia
12.
Hematol Cell Ther ; 41(1): 27-9, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10193643

RESUMO

The authors report a 58-year-old female who originally presented with acquired pure red cell aplasia (PRCA). At diagnosis, the karyotype was normal, the serum erythropoietin level was highly elevated and no T-cell mediated inhibition of erythropoiesis was demonstrated in coculture studies. Conventional immunosuppressive therapy proved ineffective. A year later a diagnosis of hyperfibrotic myelodysplastic syndrome was assessed. The sequential bone marrow examinations in the course of the three years showed a progressive increase in bone marrow fibrosis, erythroid hyperplasia and dysmegakaryocytopoiesis, terminating in the acute myeloid leukemia. This sequence of the events included the appearance of del(5)(q13q33), four years after setting a diagnosis of PRCA. The authors suggest that the absence of both cytogenetic abnormality and the signs of dyshematopoiesis at the diagnosis of PRCA does not exclude ultimately a "clonal" category of the disease. Thus, repeated hematological and cytogenetical reevaluations are recommended.


Assuntos
Leucemia Mieloide/etiologia , Síndromes Mielodisplásicas/fisiopatologia , Aplasia Pura de Série Vermelha/fisiopatologia , Doença Aguda , Feminino , Humanos , Pessoa de Meia-Idade
13.
Med Oncol ; 15(4): 275-8, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9951692

RESUMO

A 71-year-old male patient with atypical myelodysplastic syndrome showing monosomy 7 is described. He presented with severe foot pains, trophic skin and nail changes, loss of distal pulses, all compatible with peripheral arterial occlusive disease. He had completely normal blood counts and no bleeding tendency. Prolonged bleeding time was disclosed by chance, during routine haemostatic studies. An acquired platelet dysfunction was considered, with prolonged bleeding time and large platelets that failed to aggregate in response to arachidonic acid and that had impaired response to collagen and adrenaline. The bone marrow was hypercellular, with numerous dysplastic megakaryocytes and two other slightly dysplastic myeloid lines. Cytogenetic analyses of the bone marrow cells showed a mosaic karyotype: 46,XY/45,XY,-7. On angiography, bilateral thrombosis of the iliac, superficial femoral and popliteal was disclosed. The patient was prepared with platelet transfusions. Arterial thrombectomy and amputation of the left calf were performed. Ten months later, his blood counts showed mild pancytopenia. He died at home. The authors discuss some clinical and pathogenetical aspects of such presentations of myelodysplastic syndromes.


Assuntos
Plaquetas/fisiologia , Cromossomos Humanos Par 7/genética , Monossomia , Síndromes Mielodisplásicas/sangue , Idoso , Tempo de Sangramento , Contagem de Células Sanguíneas , Medula Óssea/patologia , Evolução Fatal , Humanos , Masculino , Síndromes Mielodisplásicas/complicações , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/patologia , Trombose/etiologia
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