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1.
Haemophilia ; 13(5): 451-61, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17880429

RESUMO

Acquired haemophilia is a rare bleeding disorder usually caused by the spontaneous formation of inhibitory antibodies to coagulation FVIII. The disease occurs most commonly in the elderly, and although acquired haemophilia may be associated with a variety of underlying conditions, up to 50% of reported cases are idiopathic. Treatment options have traditionally involved human FVIII or FIX replacement therapy (if the inhibitor titre allows), porcine FVIII or the use of activated pro-thrombin complex concentrates. Recombinant activated coagulation FVII (rFVIIa) was available on an emergency and compassionate use basis from 1988 to 1999 at sites in Europe and North America. It has been registered in Europe for use in treating acquired haemophilia since 1996 and has recently been licensed for this indication in the United States. By directly activating FX on the surface of activated platelets at the site of injury (thereby bypassing FVIII and FIX), rFVIIa can circumvent the actions of inhibitory antibodies present in acquired haemophilia patients. This paper provides an overview of experiences with rFVIIa for the treatment of acquired haemophilia from the NovoSeven compassionate and emergency use programmes (1989-1999), the Hemophilia and Thrombosis Research Society Registry, and independent published reports from January 1999 to September 2005. rFVIIa has been reported to provide safe and effective haemostasis as a first line therapy in patients of all ages for a variety of surgical and non-surgical bleeding situations.


Assuntos
Fator VII/uso terapêutico , Hemofilia A/tratamento farmacológico , Hemorragia/prevenção & controle , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Relação Dose-Resposta a Droga , Fator VIIa , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico , Resultado do Tratamento
2.
J Invest Surg ; 13(5): 259-63, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11071561

RESUMO

The ability of multiple oblique illumination (MOI) and high-definition microscopy (Edge R-400 3-D microscope) to improve resolution of cellular detail in the evaluation of cytopathological specimens of Pap smears and thyroid fine-needle aspirates (FNAs) has been demonstrated. However, previous experiments showed that the advantages of MOI and high-definition stereo microscopy were less certain for the breast FNAs. We hypothesized that these findings were due to the lack of sample thickness for the breast FNA specimens. To test this hypothesis, we analyzed breast FNA specimens that were significantly thicker (10.5 microm). The number of lights (1, 2, 3, 4) and the angle of light (+1.5, 0, -3) were varied independently, creating 12 groups. Three images at each combination of settings were digitally captured and analyzed to obtain a histogram. The coefficient of resolution (Cr) was calculated to mathematically evaluate the grayscale histograms for intensities (0-255), where Cr = [¿IM - IN¿ x (N)] (IM, median pixel intensity; IN, measured pixel intensity; and N, number of pixels at given intensity). Mean Cr values demonstrated that the angle of light obliquity was not a factor in altering the resolution and contrast (p = .9). However, there was a significant increase in resolution, as measured by mean Cr values, as the number of lights was successively reduced from four lights to one light. Thus, the thicker specimen did show that increases in resolution were a significant function of the number of lights utilized.


Assuntos
Neoplasias da Mama/patologia , Microscopia/instrumentação , Microscopia/métodos , Biópsia por Agulha , Feminino , Humanos , Iluminação
3.
J Surg Res ; 90(2): 113-8, 2000 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-10792950

RESUMO

BACKGROUND: Neuroblastoma is a childhood tumor that often displays unusual biological behavior. The tumor may present with widespread metastases that are unresponsive to aggressive treatment. At other times, both the metastases and the primary tumor may spontaneously regress without treatment. Apoptosis, or programmed cell death, is thought to play a role in the dichotomous behavior of neuroblastoma. We hypothesize that neuroblastoma cells will interact with host tissues to release mediators that affect apoptosis. MATERIALS AND METHODS: Human neuroblastoma cells and human Chang hepatocytes are grown in a noncontact, coculture system. After incubation for 4 days, the medium from the coculture system is collected. Neuroblastoma cells and Chang hepatocytes are then plated separately with the conditioned medium and their own standard growth medium as controls. After 4 days, these cells are harvested and cytospins made for immunostaining. Tumor necrosis factor alpha (TNF-alpha), Fas ligand, and Bcl-2, are measured with immunohistochemistry. Apoptosis is detected with the TUNEL method. Immunostaining data are interpreted with computer image analysis and reported as stain index. TUNEL data are reported as percentage apoptotic cells. All data are reported as means +/- SEM. Statistical analysis is performed and P < 0.05 considered significant. RESULTS: Chang hepatocytes grown in the coculture conditioned media have an increase in TNF-alpha and Fas ligand. The neuroblastoma cells have a significant decrease in Fas ligand. There is a significant increase in the number of apoptotic hepatocytes when they are cultured in the conditioned media. In contrast, the neuroblastoma cells grown in the coculture conditioned media show no increase in apoptosis. Finally, Bcl-2 is significantly increased in the neuroblastoma cells cultured in the conditioned media. CONCLUSIONS: Neuroblastoma cells grown in coculture conditioned media show increased expression of Bcl-2 and decreased Fas ligand levels. These changes should diminish apoptosis activity in the tumor cells. In contrast, the conditioned media induce elevated levels of proapoptotic mediators in the Chang hepatocytes. A tumor's ability to successfully metastasize may be dependent on mediators generated in the tumor-host interaction, and may not be just an independent characteristic of the tumor itself.


Assuntos
Apoptose , Técnicas de Cultura de Células/métodos , Meios de Cultivo Condicionados/farmacologia , Fígado/citologia , Neuroblastoma , Comunicação Celular/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Proteína Ligante Fas , Humanos , Citometria por Imagem , Marcação In Situ das Extremidades Cortadas , Glicoproteínas de Membrana/análise , Proteínas Proto-Oncogênicas c-bcl-2/análise , Software , Células Tumorais Cultivadas/química , Células Tumorais Cultivadas/citologia , Fator de Necrose Tumoral alfa/análise , Receptor fas/análise
4.
J Surg Res ; 88(2): 78-87, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10644471

RESUMO

PURPOSE: The goal of this study was to determine the efficacy of a single intraperitoneal administration of a chondroitin sulfate solution in preventing postoperative adhesion formation. METHODS. Twenty-five Sprague-Dawley rats had a 1-cm(2) area of cecal serosa abraded. Controls (CON, n = 5) received no treatment, the chondroitin sulfate group (CS, n = 10) received chondroitin sulfate (0.013 g/kg) in 0.9% NaCl intraperitoneally (ip), and vehicle controls (VC, n = 10) received an equal volume of 0.9% NaCl solution ip before the abdomen was closed. All animals were sacrificed on postoperative day 10. The extent of adhesion was quantified according to Mazuji's adhesion grade (0 to 4: 0 = no adhesion and 4 = very dense adhesion) and quantitated after H&E, trichome, and immunohistochemical staining for fibrin and collagen type I and type III using digital image analysis. RESULTS: The mean Mazuji's adhesion grade in the CON was 4.0 +/- 0.0, in the VC 2.60 +/- 0.37, and in the CS 1.3 +/- 0.42 (P < 0.01 for CS vs CON and P < 0.05 for CS vs VC comparisons). The mean gray-scale intensity (0-255: 0 = dense amount and 255 = none) of adhesion density in the CON was 105. 5 +/- 5.5, in the VC 125 +/- 15.0, and in the CS 178.3 +/- 21.0 (P < 0.01 for CS vs CON and P < 0.05 for CS vs VC comparisons). The mean adjusted intensity stain indices (AISI) for fibrin and collagen type I in the CON were 59 +/- 17 and 53 +/- 19, in the VC 27 +/- 3 and 25 +/- 7, and in the CS 16 +/- 5 and 6 +/- 3, respectively (P < 0.05 between CS and CON comparisons). The AISI of collagen type III was not significant among all the groups (P > 0.1). CONCLUSIONS: The extent of early postoperative intra-abdominal adhesion formation as determined by gross assessment and from quantitation of fibrin and collagen type I deposition was significantly reduced by a single intraperitoneal administration of a chondroitin sulfate solution.


Assuntos
Sulfatos de Condroitina/uso terapêutico , Doenças Peritoneais/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Aderências Teciduais/prevenção & controle , Animais , Ratos , Ratos Sprague-Dawley , Soluções
5.
Tissue Eng ; 5(6): 573-82, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10611549

RESUMO

Understanding the cellular, chemical, and physical responses of cells to stimuli is critical to successfully engineering tissue. The effect of culturing a living skin equivalent (LSE) in a submerged microgravity environment was investigated. LSEs were developed by culturing normal human epidermal keratinocyte (NHEK) on a submerged fibroblast and type 1 collagen gel matrix. Once formed, LSEs were brought up to the air/liquid interface, and after 4 days, the cultures were maintained in either (a) a normal air/liquid interface (S), (b) resubmerged in media (R), (c) folded on themselves to enclose the keratinized layer (F/R), or (d) cut into 2-4-mm fragments and suspended in a state of microgravity in a NASA-designed bioreactor (B). All groups were cultured for an average of 3 additional days. LSEs were processed for histologic evaluation. Skin cells were stained for cytokeratin to evaluate function. Images were digitally captured and processed for analysis. Parameters, including epithelial thickness, cellular areas, nuclear number, nuclear area, cytoplasmic area, and stained cytokeratin areas were measured. Removing the air/media interface significantly increased the number of NHEKs present in the skin; microgravity greatly enhanced this effect (p < 0.0001). No significant difference in cellular function as measured by protein expression [stained cytokeratin area (micro(2)) per cell] was found among the groups, though the ratio of nuclear area was significantly increased in all three groups as compared to the S group (p = 0.00227). In the case of the R and F/R groups, this appears due to the loss of the NHEK layer associated with those groups. Additionally, significant nuclear hypertrophy was demonstrated in the B group (p < 0.0001), and cellular hyperplasia was measured in all submerged groups as compared to static (p < 0.0001). Elimination of the air/liquid interface enhanced proliferation of keratinocytes. This effect was further enhanced in the presence of microgravity. No significant effect on cell function was noted with the use of this microgravity environment. We hypothesize that the increased epidermal contact plays a role in this proliferation. Microgravity is also associated with nuclear and cellular hypertrophy over and above that of the submersion methods.


Assuntos
Técnicas de Cultura de Células/métodos , Queratinócitos/citologia , Ausência de Peso , Ar , Biomarcadores/análise , Reatores Biológicos , Divisão Celular , Núcleo Celular/ultraestrutura , Técnicas de Cocultura , Colágeno , Meios de Cultura , Células Epidérmicas , Fibroblastos/citologia , Géis , Humanos , Imersão , Queratinas/análise , Masculino
6.
J Surg Res ; 84(1): 82-7, 1999 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-10334894

RESUMO

BACKGROUND: We have previously demonstrated an increase in hepatocyte apoptosis when they are cocultured with neuroblastoma cells. Death receptors in the tumor necrosis factor (TNF) family such as TNFR1 and Fas have been identified as regulators of apoptosis and may be responsible for the altered regulation of apoptosis seen in our coculture model. To evaluate the effects of released factors and remove the potential alterations induced by direct contact, a noncontact coculture system was used to study the interaction between hepatocytes and neuroblastoma cells. METHODS: Human Chang hepatocytes (HC) were plated onto Falcon cell culture inserts with 0.45-micrometer pores in the permeable membrane. Human neuroblastoma cells (NB-IMR-32) were seeded into wells of the Falcon companion plate. After 24 h, inserts containing HC were placed into wells containing NB cells and incubated for 4 days. This provided a coculture environment without actual cellular contact. Immunohistochemical staining for TNFalpha, Fas, and Fas ligand (Fas-L) was performed. Apoptosis was detected via the TUNEL method. Images were analyzed with ImagePro-Plus. Statistical analyses were done with significance determined at P < 0.05. RESULTS: Chang hepatocytes demonstrated a significant increase in the levels of TNF, Fas, and Fas-L when cocultured with neuroblastoma cells (P < 0.005). In addition, the cocultured hepatocytes had a 20-fold increase in the apoptotic rate (P < 0.001). Neuroblastoma cells had no demonstrable level of Fas or TNF when grown alone and in cocultures. Neuroblastoma cells that were grown alone had an elevated level of Fas-L, but this level diminished by 44% when cocultured with hepatocytes (P < 0.001). CONCLUSION: An upregulated TNF/Fas receptor-ligand system may be responsible for increased apoptosis in hepatocytes when cocultured with neuroblastoma. This upregulation may be due to release of neuroblastoma-derived Fas ligand into the media. Tumors may alter the regulation of apoptosis in surrounding tissues via the death receptors.


Assuntos
Apoptose/fisiologia , Fígado/fisiologia , Neuroblastoma/fisiopatologia , Receptor fas/fisiologia , Técnicas de Cocultura , Proteína Ligante Fas , Humanos , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Fígado/citologia , Fígado/metabolismo , Glicoproteínas de Membrana/metabolismo , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/metabolismo , Receptor fas/metabolismo
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