Self-organization of triblock copolymer patterns obtained by drying and dewetting.

Self-organized block copolymer structures derived from dewetting of thin films are becoming important in nanotechnology because of the various spontaneous and regular sub-micrometric surface patterns that may be obtained. Here, we report on the self-organization of a poly(styrene)-b-poly(ethene-co-butene-1)-b-poly(styrene) triblock copolymer during drying of its solution over a mica substrate. Regular submicrometric arrangements with long-range order were formed at critical polymer concentrations, consisting of parallel ribbons and hexagonal arrays of dots (droplets). This variety of highly ordered structures is explained by the interplay between forming mechanisms, mainly due to "fingering instabilities" at the three-phase line of the copolymer solution during drying. The thickness of the structures was "quantized" due to the microphase separation of the block copolymer. The formation of hexagonal patterns may be attributed to Marangoni instability at the liquid film surface prior to dewetting.

Fludarabine induces apoptosis in chronic lymphocytic leukemia - the role of P53, Bcl-2, Bax, Mcl-1, and Bag-1 proteins

The expression of P53, Bcl-2, Bax, Bag-1, and Mcl-1 proteins in CD5/CD20-positive B-chronic lymphocytic leukemia (B-CLL) cells from 30 typical CLL patients was evaluated before and after 48 h of incubation with 10-6 M fludarabine using multiparametric flow cytometric analysis. Protein expression was correlated with annexin V expression, Rai modified clinical staging, lymphocyte doubling time, and previous treatment. Our main goal was to determine the predictive value of these proteins in CLL cells in terms of disease evolution. Bcl-2 expression decreased from a median fluorescence index (MFI) of 331.71 ± 42.2 to 245.81 ± 52.2 (P < 0.001) after fludarabine treatment, but there was no difference between viable cells (331.57 ± 44.6 MFI) and apoptotic cells (331.71 ± 42.2 MFI) before incubation (P = 0.859). Bax expression was higher in viable cells (156.24 ± 32.2 MFI) than in apoptotic cells (133.56 ± 35.7 MFI) before incubation, probably reflecting defective apoptosis in CLL (P = 0.001). Mcl-1 expression was increased in fludarabine-resistant cells and seemed to be a remarkable protein for the inhibition of the apoptotic process in CLL (from 233.59 ± 29.8 to 252.04 ± 35.5; P = 0.033). After fludarabine treatment, Bag-1 expression was increased in fludarabine-resistant cells (from 425.55 ± 39.3 to 447.49 ± 34.5 MFI, P = 0.012), and interestingly, this higher expression occurred in patients who had a short lymphocyte doubling time (P = 0.022). Therefore, we could assume that Bag-1 expression in such situation might identify CLL patients who will need treatment earlier.

Fludarabine induces apoptosis in chronic lymphocytic leukemia--the role of P53, Bcl-2, Bax, Mcl-1, and Bag-1 proteins.

The expression of P53, Bcl-2, Bax, Bag-1, and Mcl-1 proteins in CD5/CD20-positive B-chronic lymphocytic leukemia (B-CLL) cells from 30 typical CLL patients was evaluated before and after 48 h of incubation with 10(-6) M fludarabine using multiparametric flow cytometric analysis. Protein expression was correlated with annexin V expression, Rai modified clinical staging, lymphocyte doubling time, and previous treatment. Our main goal was to determine the predictive value of these proteins in CLL cells in terms of disease evolution. Bcl-2 expression decreased from a median fluorescence index (MFI) of 331.71 +/- 42.2 to 245.81 +/- 52.2 (P < 0.001) after fludarabine treatment, but there was no difference between viable cells (331.57 +/- 44.6 MFI) and apoptotic cells (331.71 +/- 42.2 MFI) before incubation (P = 0.859). Bax expression was higher in viable cells (156.24 +/- 32.2 MFI) than in apoptotic cells (133.56 +/- 35.7 MFI) before incubation, probably reflecting defective apoptosis in CLL (P = 0.001). Mcl-1 expression was increased in fludarabine-resistant cells and seemed to be a remarkable protein for the inhibition of the apoptotic process in CLL (from 233.59 +/- 29.8 to 252.04 +/- 35.5; P = 0.033). After fludarabine treatment, Bag-1 expression was increased in fludarabine-resistant cells (from 425.55 +/- 39.3 to 447.49 +/- 34.5 MFI, P = 0.012), and interestingly, this higher expression occurred in patients who had a short lymphocyte doubling time (P = 0.022). Therefore, we could assume that Bag-1 expression in such situation might identify CLL patients who will need treatment earlier.

Prognosis related to staging systems for chronic lymphocytic leukemia.

CONTEXT: Chronic lymphocytic leukemia (CLL) is a clonal lymphoproliferative disorder, characterized by B lymphocytic proliferation. CLL is the most frequent adult leukemia in Western countries, accounting for 25 to 30% of all white leukemic patients. OBJECTIVE: To evaluate clinical and staging characteristics in prognosis of chronic lymphocytic leukemia. DESIGN: Evaluation of clinical-staging data. SETTING: Universidade Federal de São Paulo - Escola Paulista de Medicina / Universidade de Alfenas. SAMPLE: 73 patients diagnosed from 1977 to 1994. MAIN MEASUREMENTS: Sex, ethnic origin, age, lymphadenopathy, splenomegaly, hepatomegaly, three or more areas of lymphoid enlargement, hemoglobin (g/dl), lymphocytes/mm3, Platelets/mm3 RESULTS: Mean survival of patients was 76 months, median age was 65 years, ranging from 33 to 87. Forty-four patients (60.3%) were male and 29 (39.7%) female. CONCLUSION: The Binet system determined a better prognosis than Rai.

Frozen section biopsy of ovarian neoplasms.

In a study of the frozen section biopsy of 120 ovarian neoplasms, correct results were obtained in 94.16%, incorrect in 4.16%, and inconclusive in 1.66% of the 120 cases. The "incorrect" results were all "false-negative." No inverse "false-positive" results were recorded, and the "incorrect" results occurred in cases of encapsulated neoplasms of a macroscopically benign appearance with small areas of malignant changes detected only by paraffin block technique. The authors conclude that frozen section biopsy of ovarian neoplasm is plausible so long as a pathologist is available who can be provided with the proper equipment during the surgery and that the technique is more indicated in patients up to the age of 40 because of the necessity of conservative management in this age group.

Condicoes imunoproliferativas do intestino delgado e linfoma do Mediterraneo. / Immunoproliferative conditions of the small intestine and Mediterranean lymphoma

Os autores estudam cinco pacientes portadores de malabsorcao e diarreia que melhoraram com o emprego de antibioticos. Os referidos pacientes foram estudados atraves de tecnicas imunologicas, determinacao da perda enterica de proteinas (51Cr), avaliacao da concentracao bacteriana no delgado superior e prova da pentagastrina, ao lado de exames clinicos rotineiros.Quatro dos pacientes chegaram a laparotomia, atingindo-se os seguintes diagnosticos: tres casos de doenca de cadeia alfa, um de linfoma misto do delgado situado paraproteina IgG em um deles. Os dados clinicos, laboratoriais e histopatologicos foram comparados, formulando-se a hipotese, tendo por base essa comparacao, que a doenca de cadeia alfa ocorre em individuos com deficiencia imunologica previa. Admitem tambem, em termos hipoteticos, que a doenca, o paciente apresenta melhores condicoes imunologicas. A doenca de cadeia alfa nao corresponde sempre ao linfoma plasmocitico tendo como orientacao a classificacao de Rappaport adaptada

Hemangiopericitoma da vulva. / Hemangiopericytoma of the vulva

Apresentamos um caso de hemangiopericitoma vulvar. Tal tipo de tumor nao foi ainda descrito nesta localizacao e clinicamente apresentou-se como um tumor solido de glandula de Bartholin, em mulher de 45 anos. O diagnostico so foi possivel apos o exame anatomo-patologico da neoplasia retirada cirurgicamente

Alteracoes histopatologicas nas alcas ileais e jejunais de pacientes submetidos a operacao de by-pass para tratamento da obesidade. / Histopathological changes in the ileum and jejunum of patients subjected to a bypass operation for treatment of obesity

Sete pacientes submetidos previamente a "by-pass" intestinal pela tecnica de Scott para tratamento da obesidade foram reoperados num periodo de 18 meses a 3 anos por causas diversas. Ao lado de cuidadosa observacao macroscopica foram colhidas biopsias da parede do intestino delgado em locais predeterminados. Observou-se aumento do calibre e comprimento da alca funcionante em todos eles, enquanto a parte proximal do jejuno excluso estava consideravelmente reduzida em seu diametro. No segundo funcionamento observou-se hipertrofia da camada muscular e da mucosa, os vilos eram mais largos com o dobro ou mais do tamanho normal,com acentuado alongamento das vilosidades.Na parte distal do segmento excluido, proximal a anastomose com o sigmoide, a alca tinha calibre aumentado com hiperemia da serosa e intenso infiltrado linfoplasmocitario, possivelmente em funcao de contaminacao pela flora colonica O aspecto da mucosa mostrando consideravel aumento do numero intraluminar das celulas caliciformes sugere uma certa "colonizacao" desse segmento. Em dois casos, esse segmento estava recoberto por grande numero de pneumocistos

Biopsia pela tecnica de congelacao em neoplasias do ovario. Resultados de 120 casos. / Biopsy by freezing technic in neoplasms of the ovary. Results of 120 cases

1) A biopsia pela tecnica de congelacao em casos de neoplasias do ovario e factivel desde que se disponha de anatomopatologista munido de aparelhagem adequada, durante o ato operatorio. 2) Dos 120 casos de neoplasias do ovario nos quais se aplicou o metodo propedeutico em pauta, obtiveram-se 94,16% de resultados corretos: 4,16% de resultados incorretos e 1,66% de resultados inconclusivos. 3) Os resultados incorretos foram todos "falso-negativos", nao se registrando, ao reves, qualquer caso "falso-positivo". 4) Os resultados incorretos referem-se a neoplasias encapsuladas de aspecto macroscopico benigno, com pequenas areas de transformacao maligna detectadas somente pela tecnica de inclusao em parafina. 5) A indicacao da biopsia pela tecnica de congelacao cabe melhor nas pacientes ate 40 anos de idade, pela necessidade, quase sempre presente, de se realizarem operacoes conservadoras ate aquela idade. 6) Em nossa casuistica, 63 pacientes (52,5%) situavam-se nas faixas etarias ate 40 anos, revelando os seguintes resultados: corretos = 60 (95,2%); inccorretos = 2 (3,2%) e inconclusivos = 1 (1,6%)