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1.
BMC Cancer ; 17(1): 664, 2017 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-28969611

RESUMO

BACKGROUND: Over half of men who receive treatment for prostate suffer from a range of sexual problems that affect negatively their sexual health, sexual intimacy with their partners and their quality of life. In clinical practice, however, care for the sexual side effects of treatment is often suboptimal or unavailable. The goal of the current study is to test a web-based intervention to support the recovery of sexual intimacy of prostate cancer survivors and their partners after treatment. METHODS: The study team developed an interactive, web-based intervention, tailored to type of treatment received, relationship status (partnered/non-partnered) and sexual orientation. It consists of 10 modules, six follow the trajectory of the illness and four are theme based. They address sexual side effects, rehabilitation, psychological impacts and coaching for self-efficacy. Each includes a video to engage participants, psychoeducation and activities completed by participants on the web. Tailored strategies for identified concerns are sent by email after each module. Six of these modules will be tested in a randomized controlled trial and compared to usual care. Men with localized prostate cancer with partners will be recruited from five academic medical centers. These couples (N = 140) will be assessed prior to treatment, then 3 months and 6 months after treatment. The primary outcome will be the survivors' and partners' Global Satisfaction with Sex Life, assessed by a Patient Reported Outcome Measure Information Systems (PROMIS) measure. Secondary outcomes will include interest in sex, sexual activity, use of sexual aids, dyadic coping, knowledge about sexual recovery, grief about the loss of sexual function, and quality of life. The impact of the intervention on the couple will be assessed using the Actor-Partner Interaction Model, a mixed-effects linear regression model able to estimate both the association of partner characteristics with partner and patient outcomes and the association of patient characteristics with both outcomes. DISCUSSION: The web-based tool represents a novel approach to addressing the sexual health needs of prostate cancer survivors and their partners that-if found efficacious-will improve access to much needed specialty care in prostate cancer survivorship. TRIAL REGISTRATION: Clinicaltrials.gov registration # NCT02702453 , registered on March 3, 2016.


Assuntos
Neoplasias da Próstata/epidemiologia , Disfunções Sexuais Fisiológicas/epidemiologia , Disfunções Sexuais Psicogênicas/epidemiologia , Estresse Psicológico , Adolescente , Adulto , Feminino , Humanos , Internet , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/complicações , Neoplasias da Próstata/fisiopatologia , Neoplasias da Próstata/psicologia , Qualidade de Vida , Comportamento Sexual/fisiologia , Comportamento Sexual/psicologia , Disfunções Sexuais Fisiológicas/etiologia , Disfunções Sexuais Fisiológicas/fisiopatologia , Disfunções Sexuais Psicogênicas/etiologia , Disfunções Sexuais Psicogênicas/fisiopatologia , Parceiros Sexuais , Cônjuges/psicologia , Adulto Jovem
2.
Am J Clin Oncol ; 24(1): 99-100, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11232961

RESUMO

Clear cell carcinoma of the ovary is uncommon, and there are few reports of successful long-term therapy. In this case report, a previously healthy preadolescent presented with clear cell carcinoma of the ovary. After progressing through two regimens of chemotherapy, she was given topotecan, which arrested the disease. Nearly 3 years later, she continues to lead a near-normal life as a high school student. Our treatment plan is to continue to administer this therapy at monthly intervals until relapse. Although the achievement of stable disease with topotecan is frequently observed in patients relapsing with epithelial ovarian cancer, durable stable disease in clear cell carcinoma of the ovary is unusual. Treatment--and long-term maintenance therapy--with topotecan may be an option in such patients. In this case, the lack of cumulative toxicities allows the patient to maintain her usual daily activities.


Assuntos
Adenocarcinoma de Células Claras/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Adolescente , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bleomicina/administração & dosagem , Criança , Cisplatino/administração & dosagem , Etoposídeo/administração & dosagem , Feminino , Humanos , Qualidade de Vida , Topotecan/uso terapêutico
3.
Proc Natl Acad Sci U S A ; 98(2): 729-34, 2001 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-11136227

RESUMO

ATP-sensitive potassium channels are an octomeric complex of four pore-forming subunits of the Kir 6.0 family and four sulfonylurea receptors. The Kir 6.0 family consists of two known members, Kir 6.1 and Kir 6.2, with distinct functional properties. The tetrameric structure of the pore-forming domain leads to the possibility that mixed heteromultimers may form. In this study, we examine this by using biochemical and electrophysiological techniques after heterologous expression of these subunits in HEK293 cells. After the coexpression of Kir 6.1 and Kir 6.2, Kir 6.1 can be coimmunoprecipitated with isoform-specific Kir 6.2 antisera and vice versa. Coexpression of SUR2B and Kir 6.2 with Kir 6.1 dominant negatives at a 1:1 expression ratio and vice versa led to a potent suppression of current. Kir 6.1, and Kir 6.2 dominant negative mutants were without effect on an inwardly rectifying potassium channel from a different family, Kir 2.1. Single-channel analysis, after coexpression of SUR2B, Kir 6.1, and Kir 6.2, revealed the existence of five distinct populations with differing single-channel current amplitudes. All channel populations were inhibited by glibenclamide. A dimeric Kir 6.1-Kir 6.2 construct expressed with SUR2B had a single-channel conductance intermediate between that of either Kir 6.2 or Kir 6.1 expressed with SUR2B. In conclusion, Kir 6.1 and Kir 6.2 readily coassemble to produce functional channels, and such phenomena may contribute to the diversity of nucleotide-regulated potassium currents seen in native tissues.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Canais de Potássio Corretores do Fluxo de Internalização , Canais de Potássio/química , Isoformas de Proteínas/química , Receptores de Droga/química , Potenciais de Ação , Sequência de Aminoácidos , Animais , Biopolímeros , Linhagem Celular , Glibureto/farmacologia , Humanos , Ativação do Canal Iônico/efeitos dos fármacos , Transporte de Íons/efeitos dos fármacos , Rim/citologia , Substâncias Macromoleculares , Microscopia de Fluorescência , Dados de Sequência Molecular , Técnicas de Patch-Clamp , Fragmentos de Peptídeos/imunologia , Potássio/metabolismo , Bloqueadores dos Canais de Potássio , Canais de Potássio/genética , Canais de Potássio/imunologia , Isoformas de Proteínas/genética , Isoformas de Proteínas/imunologia , Multimerização Proteica , Subunidades Proteicas , Coelhos , Receptores de Droga/antagonistas & inibidores , Receptores de Droga/genética , Receptores de Droga/imunologia , Proteínas Recombinantes de Fusão/química , Relação Estrutura-Atividade , Receptores de Sulfonilureias , Transfecção
4.
Gen Dent ; 48(4): 406-10, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11199614

RESUMO

Research has shown bonding of restorations to tooth structure to enhance retention of the restoration to increase the fracture resistance of the tooth, and to reduce microleakage. Resin cements have superior physical properties to traditional cements such as zinc phosphate. The purpose of this study was to compare the retention of gold inlays luted with two resin cements to that of those luted with zinc phosphate cement.


Assuntos
Resinas Compostas/química , Colagem Dentária , Ligas de Ouro/química , Restaurações Intracoronárias , Cimentos de Resina/química , Estanho/química , Condicionamento Ácido do Dente , Compostos de Boro/química , Preparo da Cavidade Dentária , Esmalte Dentário/ultraestrutura , Infiltração Dentária/prevenção & controle , Adesivos Dentinários/química , Galvanoplastia , Humanos , Teste de Materiais , Metacrilatos/química , Metilmetacrilatos/química , Fosfatos/química , Estresse Mecânico , Propriedades de Superfície , Fraturas dos Dentes/prevenção & controle , Cimento de Fosfato de Zinco/química
5.
J Biol Chem ; 274(32): 22652-9, 1999 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-10428846

RESUMO

ATP-sensitive potassium channels form a link between membrane excitability and cellular metabolism. These channels are important in physiological processes such as insulin release and they are an important site of drug action. They are an octomeric complex comprised of four sulfonylurea receptors, a member of the ATP-binding cassette family of proteins, and four Kir 6.0 subunits from the inward rectifier family of potassium channels. We have investigated the nature of the interaction between SUR1 and Kir 6.2 and the domains on the channel responsible for the biochemical and functional manifestations of coupling. The results point to the proximal C terminus determining biochemical interaction in a region that also largely governs homotypic and heterotypic interaction between different Kir family members. While this domain may be necessary for functional communication between the two proteins, it is not sufficient since relative modifications of either the N or C terminus are able to disrupt many aspects of functional coupling mediated by the sulfonylurea receptor.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Trifosfato de Adenosina/farmacologia , Ativação do Canal Iônico , Canais de Potássio Corretores do Fluxo de Internalização , Canais de Potássio/metabolismo , Receptores de Droga/metabolismo , Sítios de Ligação , Relação Dose-Resposta a Droga , Humanos , Modelos Biológicos , Bloqueadores dos Canais de Potássio , Canais de Potássio/genética , Ligação Proteica , Receptores de Droga/antagonistas & inibidores , Receptores de Droga/genética , Proteínas Recombinantes de Fusão , Proteínas Recombinantes/metabolismo , Receptores de Sulfonilureias , Tolbutamida/farmacologia
6.
Urology ; 48(4): 624-7, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8886071

RESUMO

OBJECTIVES: With the increasing use of endourologic procedures to diagnose and treat urologic problems, the urologist's exposure to radiation from fluoroscopy becomes an important safety consideration. Although collimation of the x-ray beam generally prevents direct radiation exposure by the urologist, the patient absorbs radiation during the procedure and becomes a secondary source of exposure through radiation scatter. METHODS: We measured radiation exposure to the urologist during endourologic procedures using standard body shields and thyroid collars. We repeated our surveys using a newly designed urologic surgery radiation shield. RESULTS: We found dose rates to the urologist of up to 1100 mrem per hour of flouroscopy time. The maximum yearly whole-body exposure as recommended by the National Council on Radiation Protection is 5000 mrem, or 5 rem. CONCLUSIONS: Urologists should be cognizant of this radiation risk, and the concepts of time, distance, and shielding are critically important to know in efforts to reduce radiation exposure. We introduce a newly designed fluoroscopic drape which reduces the radiation dosage to the urologist from scatter nearly 70-fold. We found this shield to be very practical and easy to use, and we offer it as an effective safeguard against secondary radiation exposure.


Assuntos
Endoscopia/efeitos adversos , Fluoroscopia/efeitos adversos , Exposição Ocupacional/prevenção & controle , Proteção Radiológica/instrumentação , Urologia , Coleta de Dados , Desenho de Equipamento , Humanos
8.
Urology ; 46(4): 491-3, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7571216

RESUMO

OBJECTIVES: Urolithiasis in the morbidly obese patient presents several unique challenges to the urologist, and its treatment often requires creativity and innovation. We present a new modification of standard percutaneous nephrolithotripsy (PNL) technique, which is very helpful in overcoming some of the problems that are encountered when performing PNL in this group of patients. METHODS: We present 5 patients in whom this new technique has been used. Each had either failed prior extracorporeal shock-wave lithotripsy (ESWL) therapy or their size and abdominal girth precluded use of ESWL technology. All 5 patients underwent PNL. The radiographically measured skin-to-stone distances (determined by computed tomography or ultrasonography or both) exceeded the lengths of the standard percutaneous access sheaths and the 26 F rigid nephroscope. Thus larger and longer Amplatz access sheaths and a 30 F gynecologic laparoscope were used to reach the stones. Standard ultrasonic lithotripsy was then performed, and extralong bronchoscopic grasping forceps were used to remove stone fragments. RESULTS: All 5 patients were rendered stone-free using this technique. There was no significant perioperative morbidity. CONCLUSIONS: For this very challenging group of patients, the use of larger and longer access sheaths and the gynecologic laparoscope have been very effective additions to the urologists' armamentarium in the treatment of urolithiasis.


Assuntos
Cálculos Renais/terapia , Litotripsia/métodos , Nefrostomia Percutânea/métodos , Obesidade Mórbida/complicações , Adulto , Idoso , Desenho de Equipamento , Feminino , Humanos , Cálculos Renais/complicações , Masculino , Pessoa de Meia-Idade , Nefrostomia Percutânea/instrumentação
9.
J Urol ; 150(2 Pt 2): 759-62, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8392121

RESUMO

Single photon emission computerized tomography (SPECT) scintigraphy has proved to be an extremely sensitive renal imaging modality in children with genitourinary pathology, including pyelonephritis, particularly when compared to 2-dimensional planar imaging. This study was undertaken to corroborate SPECT dimercaptosuccinic acid (DMSA) scintigraphic findings with specific histopathology in acute pyelonephritis. Unilateral vesicoureteral reflux was produced in 19 Yorkshire piglets 3 to 4 weeks old. The bladders of 12 animals were inoculated with Escherichia coli 2 weeks later, after baseline SPECT DMSA scans had been obtained. The animals were then re-imaged at 3 (4), 7 (4) or 14 (4) days after infection and sacrificed for histological evaluation. Seven purposefully uninfected piglets with unilateral reflux served as controls and were followed for up to 6 weeks before imaging and sacrifice. SPECT proved to be 97% sensitive and 93% specific in providing the diagnosis of acute pyelonephritis. The SPECT findings were manifest by a spectrum of abnormal findings (mottling, striations, inner cortical scalloping and focal cortical defects), which correlated precisely with the extent and severity of cortical involvement in the acute pyelonephritic process. We propose a new classification scheme for SPECT DMSA renal scintigraphic imaging, and believe that this modality is exquisitely sensitive in providing the diagnosis as well as in evaluating the extent of renal parenchymal involvement when acute pyelonephritis is induced in the animal model.


Assuntos
Pielonefrite/diagnóstico por imagem , Succímero , Tomografia Computadorizada de Emissão de Fóton Único , Doença Aguda , Animais , Rim/diagnóstico por imagem , Rim/patologia , Pielonefrite/patologia , Sensibilidade e Especificidade , Suínos
10.
Cancer Res ; 50(8): 2322-9, 1990 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-2156617

RESUMO

Metalloproteinases have been implicated as important factors mediating the tissue migration of a variety of normal and transformed cells. The conditioned medium (CM) of fetal human astrocytes and five glioma cell lines did not degrade azocoll in suspension, but several proteolytic activities, inhibitable by 1,10-phenanthroline, were detected on sodium dodecyl sulfate-polyacrylamide gels containing gelatin. Both cell types secreted three major proteolytic species (Mr 65,000, 57,000, and 52,000). Two of the glioma lines secreted an additional proteinase (Mr 92,000). After treatment with 12-O-tetradecanoylphorbol-13-acetate, the secretion of the Mr 92,000, 57,000, and 52,000 proteinases was induced or enhanced in all of the cells. The Mr 92,000 and 65,000 proteinases bound specifically to a gelatin affinity column. When purified by preparative gel electrophoresis, the Mr 65,000 proteinase was found to degrade type IV procollagen. The Mr 57,000 and 52,000 species were precipitated by anticollagenase IgG. Tissue inhibitor of metalloproteinases was detected in the CM of all of the cells by substrate gel analysis and immunoprecipitation of [35S]methionine-labeled proteins with anti-tissue inhibitor of metalloproteinases IgG. The glioma lines also secreted various amounts of two smaller inhibitors of metalloproteinases (IMPs), also seen in rabbit brain capillary endothelial cell CM (IMP-1 at Mr 22,000 and IMP-2 at Mr 19,000), and an inhibitor not previously identified (IMP-3 at Mr 16,500). 12-O-Tetradecanoylphorbol-13-acetate stimulated the secretion of tissue inhibitor of metalloproteinases in all of the cells and induced IMPs in some of the glioma lines. When gel filtration chromatography of concentrated CM was used to resolve inhibitors from proteinases, the isolated proteinases had activity against azocoll and the glycoprotein and collagen components of an in vitro model of the extracellular matrix. The secretion of a battery of metalloproteinases by astrocytes may be important in facilitating astrocytic migration during development and in pathological conditions such as inflammation or local invasion of astrocytic neoplasms.


Assuntos
Astrócitos/metabolismo , Glicoproteínas/biossíntese , Metaloendopeptidases/biossíntese , Colagenase Microbiana/biossíntese , Células Tumorais Cultivadas/metabolismo , Astrócitos/enzimologia , Encéfalo/metabolismo , Linhagem Celular , Células Cultivadas , Feto , Glioblastoma , Glioma , Glicoproteínas/isolamento & purificação , Humanos , Metaloendopeptidases/antagonistas & inibidores , Metaloendopeptidases/isolamento & purificação , Metionina/metabolismo , Colagenase Microbiana/isolamento & purificação , Peso Molecular , Radioisótopos de Enxofre , Inibidores Teciduais de Metaloproteinases , Células Tumorais Cultivadas/enzimologia
11.
Int J Prosthodont ; 3(1): 72-7, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2372368

RESUMO

The potential for disease transmission has increased the importance of infection control in the dental laboratory. Impressions must be disinfected without altering their accuracy. The purpose of this study was to determine the dimensional stability of three impression materials: irreversible hydrocolloid, reversible hydrocolloid, and poly(vinyl siloxane). Thirty-six impressions were made with each material and divided into control, 10-minute, and 30-minute immersion groups using an iodophor as the disinfectant. A microscope was used to measure dimensional changes in the stone casts made from each group of impressions, and the percent change was analyzed using a two-way ANOVA. All dimensional changes after iodophor disinfection were small and within established limits.


Assuntos
Coloides , Materiais para Moldagem Odontológica , Desinfetantes/efeitos adversos , Iodo/efeitos adversos , Iodóforos/efeitos adversos , Polivinil , Silicones , Siloxanas , Análise de Variância , Análise do Estresse Dentário
12.
J Neurosurg ; 71(6): 875-83, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2585080

RESUMO

The effect of concentrated conditioned medium from each of eight human malignant glioma cell lines on the growth of indicator cells (normal rat kidney fibroblasts (NRK), clone 14) was determined in monolayer and in soft agar assay systems. The conditioned medium from all cell lines was mitogenic in the monolayer assay, but only SF-210, U-343 MG-A, and U-251 MG produced soluble factors that caused NRK cells to grow in soft agar. The soluble growth-promoting factors from these three cell lines were acid- and heat-stable (60 degrees C for 30 minutes) but were inactivated by trypsin (100 microns/ml) and dithiothreitol (50 microM). The growth factors from SF-210 and U-343 MG-A were further purified by molecular-sieve chromatography. The partially purified growth factor from U-343 MG-A retained transforming growth factor (TGF)-like activity, had a molecular weight of 9 kD, was potentiated by TGF-beta in the soft agar assay, competed effectively with 125I-epidermal growth factor (EGF) radiolabeled for the EGF receptor on A 431 epidermoid carcinoma cells, and was completely inhibited by monoclonal antibodies to TGF-alpha. The partially purified growth factor from SF-210 had a molecular weight of 17 kD, was not inhibited by monoclonal antibodies to platelet-derived growth factor (PDGF) or TGF-alpha, and did not bind to a heparin-Sepharose column. These results imply that U-343 MG-A secretes a growth factor with TGF-alpha-like activity, and SF-210 secretes a TGF with neither TGF-alpha nor TGF-beta activity.


Assuntos
Glioma/análise , Fatores de Crescimento Transformadores/isolamento & purificação , Ágar , Animais , Fenômenos Químicos , Físico-Química , Cromatografia em Gel , Meios de Cultura , Receptores ErbB/análise , Fibroblastos/efeitos dos fármacos , Humanos , Rim/citologia , Fatores de Crescimento Transformadores/farmacologia , Células Tumorais Cultivadas
13.
Ann R Australas Coll Dent Surg ; 10: 115-9, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2489010

RESUMO

This presentation will briefly consider past uses of gold compared with currently available dental materials for the restoration of teeth. A progressive analysis of stresses involved versus the mechanical and behavioural properties of contemporary materials will provide insight into the selection of appropriate materials for specific restorative situations. The place of gold-based restorations will be discussed and the future of these more durable prostheses will become apparent.


Assuntos
Restauração Dentária Permanente/tendências , Ligas de Ouro , Resinas Compostas , Amálgama Dentário , Cimentos de Ionômeros de Vidro , Humanos
14.
Int J Cancer ; 42(3): 419-27, 1988 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-3417370

RESUMO

We studied the effect of retinoids on the growth and differentiation of a cell line (U 343 MG-A) derived from a human malignant astrocytoma. Cultures treated with all-trans or 13-cis retinoic acid showed a dose-dependent inhibition of proliferation and a marked reduction in the mean cell number at the plateau phase of growth (3.5 x 10(6) vs. 1 x 10(7) cells/25 cm2) compared with untreated cultures. At confluence, cells treated with all-trans or 13-cis retinoic acid were contact-inhibited, whereas control cultures showed crowding, piling, and overgrowth. All-trans retinol or retinyl acetate did not inhibit growth. Astrocytoma cultures treated with all-trans retinoic acid (10(-6) M) for 5 days were modestly growth-inhibited but by day 16 had the same numbers of cells as controls; cultures that received all-trans retinoic acid for 9 days were markedly growth-inhibited for 7 days after the drug was removed. All-trans and 13-cis retinoic acid (10(-6) M) prevented the EDTA-induced cell detachment seen in control cultures. Strongly adherent all-trans retinoic-acid-treated astrocytoma cells grew at a slower rate than did readily detached all-trans retinoic-acid-treated or control cells. Cell spreading, an increased cytoplasmic:nuclear ratio, and greater numbers of broadly bipolar cells, some bearing thin cytoplasmic processes, were seen in cultures treated with 10(-6) M all-trans or 13-cis retinoic acid. Small tightly packed cuboidal cells and large broadly bipolar cells were seen in astrocytoma cultures from which all-trans retinoic acid was removed on days 5 and 9. Indirect immunofluorescence revealed more intense staining with antiserum to glial fibrillary acidic protein in cultures treated with 10(-6) M all-trans retinoic acid than in control cultures; electron-microscope examination of similarly treated cultures revealed more abundant 8-10 nm intermediate filaments than in control cultures. An enzyme-linked immunosorbent assay showed that all-trans or 13-cis retinoic acid caused a dose-dependent increase in the quantity of glial fibrillary acidic protein in the astrocytoma cells.


Assuntos
Astrocitoma/patologia , Proteína Glial Fibrilar Ácida/análise , Retinoides/farmacologia , Astrocitoma/análise , Astrocitoma/ultraestrutura , Adesão Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Timidina/metabolismo , Tretinoína/farmacologia , Células Tumorais Cultivadas
15.
Int J Cancer ; 41(4): 573-82, 1988 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-2833452

RESUMO

To determine whether tumor necrosis factor is of potential value for the treatment of human malignant gliomas, we studied the effects of human recombinant tumor necrosis factor (rTNF-alpha) on the morphology, incorporation of tritiated thymidine, and proliferation of 5 established cell lines derived from human malignant gliomas and 3 normal human brain cell cultures. A radioreceptor analysis for rTNF-alpha was performed on all cell lines and cultures. Two of the 5 human glioma cell lines (SF-188 and U 343 MG-A) demonstrated a marked decrease (60% or less of untreated controls) in the uptake of tritiated thymidine when treated with rTNF-alpha at a concentration of 40 U/ml; rTNF-alpha at 100 U/ml had antiproliferative and cytotoxic effects on both cell lines. The growth and proliferation of cell lines SF-126 and U 251 MG were not affected by rTNF-alpha even at high concentrations (5,000 U/ml). The growth and proliferation of SF-539 were affected to an intermediate degree. A colony-forming efficiency assay corroborated the results of the proliferation studies: SF-126 was relatively resistant (surviving fraction of 0.9 at 500 U/ml) and SF-188 was relatively sensitive (surviving fraction of 0.08 at 500 U/ml) to the cytotoxic effects of rTNF-alpha. Time-sequence electron microscopy showed that rTNF-alpha at a concentration of 500 U/ml caused ultrastructural changes in SF-188, including increased intracytoplasmic vesiculation, swelling and degeneration of mitochondria, loss of cell:cell junctional complexes, and fragmentation of the plasma membrane. Studies with 125I-rTNF-alpha showed a variable degree of binding in all cell lines and cultures. SF-188, a highly sensitive cell line, demonstrated the strongest binding of 125I-rTNF-alpha (3,400 receptors/cell with high affinity; kd = 0.27 nM), while SF-126, a highly resistant cell line, had the weakest binding (809 receptors/cell; kd = 0.25 nM). We conclude that there is a spectrum of antiproliferative and cytotoxic activity among glioma-derived tumor cell lines exposed to rTNF-alpha. An increased number of rTNF-alpha receptors appears to be a necessary but insufficient condition to explain the antiproliferative effects observed in some glioma-derived cell lines.


Assuntos
Glioma/patologia , Fator de Necrose Tumoral alfa/farmacologia , Divisão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Glioma/ultraestrutura , Humanos , Ensaio Radioligante , Receptores de Superfície Celular/análise , Receptores do Fator de Necrose Tumoral , Proteínas Recombinantes/farmacologia , Timidina/metabolismo , Células Tumorais Cultivadas/efeitos dos fármacos
16.
J Neurosurg ; 68(2): 251-8, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3339442

RESUMO

To determine how medulloblastoma cells might influence the proliferation and phenotype of normal stromal cells, normal human leptomeningeal cells were treated in culture with medulloblastoma-conditioned medium; their ability to incorporate tritiated thymidine and synthesize collagen was measured. The treated leptomeningeal cells had a significantly greater uptake of tritiated thymidine and grew faster than control leptomeningeal cells. Immunofluorescence studies demonstrated a greater intensity of staining for procollagen type III in the cell layer of the treated cultures than in control cultures; diethylaminoethyl (DEAE)-cellulose chromatography of the medium showed that the treated cells synthesized predominantly type III collagen, whereas control cells synthesized type I collagen. Analysis of the medulloblastoma-conditioned medium revealed that the soluble factor responsible for these effects in an acid- and heat-stable protein. The increased proliferation and altered collagen synthesis induced in leptomeningeal cell cultures by a soluble factor from a medulloblastoma are examples of how tumor and stromal elements interact, and may be related to the process of desmoplasia often observed in medulloblastomas in vivo.


Assuntos
Divisão Celular , Colágeno/biossíntese , Substâncias de Crescimento/análise , Meduloblastoma/fisiopatologia , Meninges/fisiopatologia , Linhagem Celular , Células Cultivadas , Criança , Meios de Cultura , Feminino , Humanos , Masculino , Meninges/citologia , Meninges/metabolismo , Pessoa de Meia-Idade
17.
Br J Neurosurg ; 2(2): 227-34, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3267306

RESUMO

Three in vitro clonogenic assays were used to determine the sensitivity of an established human glioblastoma cell line (U251-MG) to five chemotherapeutic agents. The colony-forming efficiency of untreated culture was 0.695 +/- 0.170 in a monolayer assay with irradiated feeder cells, 0.018 +/- 0.006 in a low-O2 agar assay, and 0.049 +/- 0.021 in a two-layer agar system with nutrient-enriched medium (p less than 0.001). Comparison of the slope of the regression line for the dose-response curve and the interpolated ID90 for each drug showed that U251-MG was equally sensitive to aziridinylbenzoquinone and dianhydrogalactitol in all three assays. The sensitivity of this cell line to 1,3-bis-(2-chloroethyl)-1-nitrosourea (BCNU), cis-dichlorodiammineplatinum (II) (CDDP) and 9-hydroxy-2-N-methylellipticine (HME), however, varied depending on the assay used. In no instance did U251-MG show greater sensitivity (lower ID90 or steeper slope) in the low-O2 agar assay than in the other assays. BCNU and CDDP were least active in the monolayer assay, whereas HME showed both the lowest ID90 and steepest slope using this technique. We conclude that different in vitro tumour clonogenic assays show different colony-forming efficiencies for the same cell line and may show different responses to certain drugs. Identification of accurate predictive models of drug sensitivity will require correlative in vivo and in vitro studies.


Assuntos
Antineoplásicos/farmacologia , Benzoquinonas , Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Células Tumorais Cultivadas/efeitos dos fármacos , Ensaio Tumoral de Célula-Tronco/métodos , Antineoplásicos/uso terapêutico , Aziridinas/farmacologia , Aziridinas/uso terapêutico , Carmustina/farmacologia , Carmustina/uso terapêutico , Ensaio de Unidades Formadoras de Colônias , Cicloexenos , Humanos , Células Tumorais Cultivadas/citologia
19.
Neurosurgery ; 21(6): 872-8, 1987 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3437956

RESUMO

Well-characterized medulloblastoma cells growing in suspension were placed on top of a confluent monolayer of leptomeningeal cells. In contrast to cells placed on plastic alone, which did not grow or attach, the medulloblastoma cells attached readily to the leptomeningeal cells and grew to form enlarging spheroids. The growth of these spheroids was supported with minimal essential medium containing 10% fetal calf serum or with human cerebrospinal fluid. Medulloblastoma cells grown on plastic remained viable for 7 to 10 days, whereas those grown on a monolayer of leptomeningeal cells remained viable for 40 days. Electron microscopy demonstrated increased interdigitation of the plasma membrane at the sites of contact between leptomeningeal and medulloblastoma cells, the deposition of fine, basement membrane-like material between the two cell types, and an increased number of cytoskeletal filaments in the leptomeningeal cells. We conclude that medulloblastoma cells can be grown on a leptomeningeal monolayer. This in vitro system may be useful in studying the mechanisms by which medulloblastoma cells attach to leptomeningeal elements and grow after dissemination in cerebrospinal fluid.


Assuntos
Aracnoide-Máter/citologia , Adesão Celular , Meduloblastoma/metabolismo , Pia-Máter/citologia , Células Tumorais Cultivadas/metabolismo , Aracnoide-Máter/metabolismo , Criança , Humanos , Masculino , Meduloblastoma/patologia , Meduloblastoma/ultraestrutura , Microscopia Eletrônica , Pia-Máter/metabolismo , Células Tumorais Cultivadas/ultraestrutura
20.
Cancer Res ; 47(13): 3515-22, 1987 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-3555773

RESUMO

We devised a model system to study the effects of extracellular matrix proteins on the malignant phenotype of an anaplastic glioma cell line, U 343 MG-A. Well-characterized cultures derived from normal human leptomeninges were grown to confluence and maintained for 2 weeks. The leptomeningeal cells were then removed with base and detergent, leaving behind an extracellular matrix enriched in laminin, fibronectin, type I and IV collagen, and procollagen III. U 343 MG-A tumor cells planted on top of this normal extracellular matrix were profoundly growth inhibited compared with glioma cells grown on plastic alone. Glioma cells grown on the extracellular matrix developed multiple, slender processes and assumed a more differentiated astrocytic phenotype; immunostains for glial fibrillary acidic protein revealed a more extensive intracytoplasmic network of intensely staining filaments than in control glioma cells. When glioma cells grown on the extracellular matrix were analyzed by an enzyme-linked immunosorbent assay for glial fibrillary acidic protein, the amount of this intermediate filament per cell was increased 20-fold compared with glioma cells growing on plastic. The growth and differentiation of U 343 MG-A glioma cells in flasks coated with purified fibronectin or laminin was not significantly perturbed; however, glioma cell cultures grown in flasks coated with purified type I or IV collagen showed decreased cellular proliferation, stellate cell formation, and increased levels of glial fibrillary acidic protein per cell compared with glioma cells growing on plastic. Gelatin gel analysis showed that U 343 MG-A glioma cells growing on plastic secreted a 65,000-D metalloproteinase that was not secreted by glioma cells grown on the leptomeningeal extracellular matrix. We conclude that in this system, the extracellular matrix of a normal human leptomeningeal culture substantially inhibited the proliferation of and induced differentiation in an anaplastic glioma cell line. Our analysis of single components of the extracellular matrix suggests that these effects may be mediated in part by type I and IV collagen. The mechanism by which the leptomeningeal extracellular matrix inhibits glioma cell proliferation may be by diminishing tumor-associated protease secretion so that the degradation of extracellular matrix macromolecules in the tumor cell microenvironment is prevented and tumor cell migration becomes less likely.


Assuntos
Matriz Extracelular/fisiologia , Glioma/patologia , Diferenciação Celular , Divisão Celular , Linhagem Celular , Colágeno/fisiologia , Fibronectinas/fisiologia , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Laminina/fisiologia , Meninges/ultraestrutura , Peptídeo Hidrolases/metabolismo
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