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1.
Public Health ; 178: 72-77, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31627054

RESUMEN

OBJECTIVES: The growing body of evidence documenting the effectiveness of brace treatment for scoliosis has renewed interest in potential benefits of early detection through school screening. We aimed to assess the prevalence and identify barriers of screening. We hypothesized that school screening is more frequent in schools that have a nurse on staff compared to schools without nurse on staff. STUDY DESIGN: A questionnaire survey. METHODS: All schools located in four counties in Louisiana, United States of America comprising the New Orleans metropolitan area between September 2015 and January 2016 were contacted by phone to assess rates of scoliosis screening, report the availability of a school nurse, and specify barriers if screening was not performed. RESULTS: Two hundred and ninety-one schools responded to the survey including 152 public, 30 charter, and 109 private schools (101 had religious affiliation). A staff nurse was available in 180 schools (61.8%). Only 21 schools (7.2%) performed scoliosis screening. The majority were charter schools (11 schools), while six were private and four were public (P < 0.0001). Of these 21 schools, 16 (76.2%) had a nurse on staff while five schools did not (P = 0.16). Lack of a referral pathway in the event of a positive screen was the most common barrier to performing scoliosis screening. CONCLUSION: Scoliosis screening is infrequent in the examined school districts. Efforts to support school screening can facilitate clear referral pathways for schools in the event of a positive screen. These findings suggest a potential need for different pathway of scoliosis screening. Pediatricians and family physicians can assist with scoliosis screening during the annual visit. While universal screening is overburdensome and likely unnecessary, targeted screening of underserved populations may prove to be beneficial. Further investigation should include assessment of the economic viability of targeted screening programs. LEVEL OF EVIDENCE: IV.


Asunto(s)
Tamizaje Masivo/estadística & datos numéricos , Servicios de Salud Escolar/estadística & datos numéricos , Escoliosis/diagnóstico , Adolescente , Niño , Femenino , Encuestas de Atención de la Salud , Humanos , Masculino , Tamizaje Masivo/métodos , Nueva Orleans/epidemiología , Prevalencia , Derivación y Consulta/organización & administración , Escoliosis/epidemiología , Poblaciones Vulnerables/estadística & datos numéricos
2.
Semin Cutan Med Surg ; 20(1): 2-13, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11308133

RESUMEN

Antinuclear antibodies are used in the diagnosis and evaluation of patients with connective tissue diseases. The study of antinuclear antibodies has also fundamentally expanded our understanding of nuclear anatomy and function. This article reviews the clinically relevant antinuclear antibodies and their disease associations. Developing an understanding of the utilities and limitations of antinuclear antibodies is essential to providing the expert diagnoses prognoses, and care expected of a dermatologist.


Asunto(s)
Anticuerpos Antinucleares/análisis , Enfermedades del Tejido Conjuntivo/diagnóstico , Técnica del Anticuerpo Fluorescente/métodos , Enfermedades de la Piel/diagnóstico , Autoanticuerpos/análisis , Enfermedades del Tejido Conjuntivo/inmunología , Humanos , Lupus Eritematoso Cutáneo/diagnóstico , Lupus Eritematoso Sistémico/diagnóstico , Esclerodermia Sistémica/diagnóstico , Enfermedades de la Piel/inmunología
3.
Cancer ; 88(5): 1082-90, 2000 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-10699899

RESUMEN

BACKGROUND: Pamidronate therapy previously has been shown to reduce skeletal complications effectively for up to 12 months in breast carcinoma patients with bone metastases. The current study data provide further follow-up results regarding the effects of long term (up to 24 months) pamidronate treatment in women with breast carcinoma and osteolytic metastases. METHODS: Follow-up results from two prospective, multicenter, randomized, double-blind, placebo-controlled intervention trials conducted at academic and community oncology centers were combined to provide a large data set with which to evaluate the long term efficacy and safety of pamidronate therapy. Seven hundred fifty-four women with Stage IV breast carcinoma and osteolytic metastases were randomized to the 2 treatment arms of the trial. Three patients were excluded from the intent-to-treat population for the analysis. A total of 751 evaluable patients were randomized to receive either a 90-mg intravenous pamidronate infusion (367 patients) or a placebo infusion (384 patients) every 3-4 weeks. The primary outcome measures were skeletal morbidity rate (events/year), proportion of patients developing a skeletal complication, and time to first skeletal complication. RESULTS: Of the 367 women receiving pamidronate, 115 (31.3%) completed the trial and 81 (22.1%) discontinued the study due to adverse events. Of the 384 women who received placebo, 100 (26.0%) completed the study and 76 (19.8%) discontinued the study due to adverse events. The skeletal morbidity rate was 2.4 in the pamidronate group and 3.7 in the placebo group (P < 0.001). In the pamidronate group, 186 of the 367 patients (51%) had skeletal complications compared with 246 of the 384 patients in the placebo group (64%) (P < 0.001). The median time to first skeletal complication was 12.7 months in the pamidronate group and 7 months in the placebo group (P < 0.001). Six patients treated with pamidronate discontinued treatment due to drug-related adverse events. Pain and analgesic scores were significantly worse in the placebo group compared with those patients in the pamidronate group. CONCLUSIONS: In the current study, monthly infusions of 90 mg of pamidronate as a supplement to antineoplastic therapy were found to be well tolerated and superior to antineoplastic therapy alone in preventing skeletal complications and palliating symptoms for at least 24 months in breast carcinoma patients with osteolytic bone metastases.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/secundario , Neoplasias de la Mama/patología , Difosfonatos/uso terapéutico , Osteólisis/prevención & control , Cuidados Paliativos , Anciano , Antineoplásicos/efectos adversos , Neoplasias Óseas/patología , Neoplasias de la Mama/complicaciones , Difosfonatos/efectos adversos , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Osteólisis/complicaciones , Osteólisis/patología , Dolor/etiología , Pamidronato , Estudios Prospectivos , Calidad de Vida
4.
J Pept Res ; 56(6): 388-97, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11152298

RESUMEN

The three-dimensional solution structure of antiobesity drug (AOD), a 15-residue, disulfide-bonded, cyclic peptide, cyclo(6,13)-H2N-Leu-Arg-Ile-Val-Gln-Cys-Arg-Ser-Val-Glu-Gly-Ser-Cys-Gly-Phe-OH, derived from the C-terminal domain of the human growth hormone (hGH) (residues 177-191) was determined using two-dimensional 1H NMR spectroscopy. AOD stimulates lipolysis and inhibits lipogenesis, in vitro, in rodent, porcine and human adipose tissues. These biological effects suggest that AOD is a potential therapeutic candidate for the treatment of obesity. Conformational studies of AOD were conducted in aqueous solution and in water/dimethylsulfoxide mixtures. In general, spectral quality was superior in the water/ dimethylsulfoxide mixtures. The cyclic region of AOD in water/dimethylsulfoxide adopts type I beta-turns at residues Ser8-Val9-Glu10-Gly11 and Ser12-Cys13-Gly14-Phe15, each preceded by loop-like structures. Comparison of the conformation of this peptide with residues 177-191 in the native hGH protein X-ray crystal structure indicates that the synthetic peptide retains some structural similarity to the intact protein. This study provides evidence that the C-terminal region of hGH is a specific functional domain of the multifunctional hGH protein.


Asunto(s)
Hormona de Crecimiento Humana/química , Hormona de Crecimiento Humana/fisiología , Péptidos/química , Tejido Adiposo/química , Alanina/química , Secuencia de Aminoácidos , Animales , Cristalografía por Rayos X , Humanos , Lipólisis , Espectroscopía de Resonancia Magnética , Ratones , Ratones Endogámicos C57BL , Modelos Moleculares , Datos de Secuencia Molecular , Biosíntesis de Péptidos , Conformación Proteica , Estructura Secundaria de Proteína , Porcinos
5.
J Clin Oncol ; 17(3): 846-54, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10071275

RESUMEN

PURPOSE: To assess whether pamidronate can reduce the frequency of skeletal morbidity in women with lytic bone metastases from breast cancer treated with hormone therapy. PATIENTS AND METHODS: Three hundred seventy-two women with breast cancer who had at least one lytic bone lesion and who were receiving hormonal therapy were randomized to receive 90 mg of pamidronate or placebo as a 2-hour intravenous infusion given in double-blind fashion every 4 weeks for 24 cycles. Patients were evaluated for skeletal complications: pathologic fractures, spinal cord compression, irradiation of or surgery on bone, or hypercalcemia. The skeletal morbidity rate (the ratio of the number of skeletal complications to the time on trial) was the primary efficacy variable. Bone pain, use of analgesics, quality of life, performance status, bone tumor response, and biochemical parameters were also evaluated. RESULTS: One hundred eighty-two patients who received pamidronate and 189 who received placebo were assessable. The skeletal morbidity rate was significantly reduced at 12, 18, and 24 cycles in patients treated with 90 mg of pamidronate (P = .028, .023, and .008, respectively). At 24 cycles, the proportion of patients having had any skeletal complication was 56% in the pamidronate group and 67% in the placebo group (P = .027). The time to the first skeletal complication was longer for patients receiving pamidronate than for those given placebo (P = .049). There was no statistical difference in survival or in objective bone response rate. Pamidronate was well tolerated. CONCLUSION: Treatment with 90 mg of pamidronate as a 2-hour intravenous infusion every 4 weeks in addition to hormonal therapy significantly reduces skeletal morbidity from osteolytic metastases.


Asunto(s)
Antineoplásicos/uso terapéutico , Enfermedades Óseas/tratamiento farmacológico , Neoplasias de la Mama/tratamiento farmacológico , Difosfonatos/uso terapéutico , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Enfermedades Óseas/complicaciones , Enfermedades Óseas/patología , Neoplasias de la Mama/complicaciones , Quimioterapia Adyuvante , Difosfonatos/administración & dosificación , Método Doble Ciego , Femenino , Humanos , Hipercalcemia/complicaciones , Megestrol/administración & dosificación , Persona de Mediana Edad , Metástasis de la Neoplasia , Pamidronato , Tamoxifeno/administración & dosificación
6.
J Clin Oncol ; 16(6): 2038-44, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9626201

RESUMEN

PURPOSE: Pamidronate, an aminobisphosphonate, has been shown to lower the risk of skeletal complications associated with lytic bone lesions for up to 1 year in women with stage IV breast cancer who received chemotherapy. We studied the long-term effectiveness and safety of continued treatment with intravenous pamidronate infusions for up to 2 years. PATIENTS AND METHODS: Three hundred eighty-two women with metastatic breast cancer and lytic bone lesions who received chemotherapy were randomly assigned to receive either 90 mg of pamidronate or placebo intravenously every 3 to 4 weeks in this double-blind, multicenter, parallel-group trial. Patients were evaluated monthly for 2 years for skeletal complications, which included pathologic fractures, need for radiation or surgery to treat bone complications, spinal cord compression, and hypercalcemia. Bone pain, analgesic use, bone biochemical markers, performance status, quality of life, radiologic response in bone, and survival were also evaluated. RESULTS: As in the first year of treatment, the proportion of patients with any skeletal complication was significantly less for the pamidronate than the placebo group at 15, 18, 21, and 24 months (P < .001). The proportions of patients with any pathologic fracture (i.e., vertebral and nonvertebral fractures), need for radiation or surgery to treat bone complications, and hypercalcemia were also statistically less for the pamidronate than the placebo group. The median time to the first skeletal complication was 13.9 months in the pamidronate-treated women and 7.0 months in the placebo group (P < .001). Long-term treatment did not result in any unexpected adverse events. Survival did not differ between the two groups. CONCLUSION: The risk for osteolytic bone lesion complications in metastatic breast cancer was significantly decreased with monthly infusions of 90 mg of pamidronate, and this effect was maintained for at least 2 years. Pamidronate is a useful adjunct to standard chemotherapy in the palliative treatment of metastatic breast cancer.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/complicaciones , Difosfonatos/administración & dosificación , Osteólisis/prevención & control , Fosfatasa Alcalina/sangre , Analgésicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/mortalidad , Calcio/orina , Creatinina/orina , Difosfonatos/efectos adversos , Método Doble Ciego , Femenino , Humanos , Hidroxiprolina/orina , Osteólisis/sangre , Osteólisis/complicaciones , Osteólisis/orina , Dolor/tratamiento farmacológico , Dolor/epidemiología , Pamidronato , Tasa de Supervivencia , Resultado del Tratamiento
7.
Am J Dermatopathol ; 20(2): 213-7, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9557795

RESUMEN

We describe an unusual dermal neoplasm with epithelioid morphology. A 44-year-old man presented with a solitary, tender, 4-mm nodule on the leg. Excisional biopsy showed several well-circumscribed dermal epithelioid tumor nodules, prominent vascularity, and smooth muscle differentiation. We suggest the term cutaneous epithelioid angioleiomyoma for this neoplasm. In a review of the literature, we found reports of two similar cases and a recent report describing five cutaneous epithelioid leiomyosarcomas. Cutaneous epithelioid angioleiomyoma represents a rare variant of dermal smooth muscle tumor and could represent the benign counterpart to the recently described epithelioid leiomyosarcoma of the skin.


Asunto(s)
Angiomioma/patología , Leiomioma Epitelioide/patología , Neoplasias Cutáneas/patología , Actinas/análisis , Adulto , Angiomioma/química , Antígenos CD34/análisis , Biomarcadores de Tumor/análisis , Humanos , Inmunohistoquímica , Leiomioma Epitelioide/química , Masculino , Neoplasias Cutáneas/química
9.
J Clin Oncol ; 16(2): 593-602, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9469347

RESUMEN

PURPOSE: To determine the efficacy and safety of 21 monthly cycles of pamidronate therapy in patients with advanced multiple myeloma. PATIENTS AND METHODS: Patients with stage III myeloma and at least one lytic lesion received either placebo or pamidronate 90 mg intravenously administered as a 4-hour infusion monthly for 21 cycles. At study entry, the patients were stratified according to whether they were to receive first-line (stratum 1) or second-line (stratum 2) antimyeloma chemotherapy. Skeletal events (pathologic fracture, radiation or surgery to bone, and spinal cord compression) and hypercalcemia were assessed monthly. RESULTS: The results of the first nine previously reported cycles are extended to 21 cycles. Of the 392 randomized patients, efficacy could be evaluated in 198 who received pamidronate and 179 who received placebo. After 21 cycles, the proportion of patients who developed any skeletal event was lower in the pamidronate-group (P = .015). The mean number of skeletal events per year was less in the pamidronate-group (1.3) than in placebo-treated patients (2.2; P = .008). Although survival was not different between the pamidronate-treated group and placebo patients overall, stratum 2 patients who received pamidronate lived longer than those who received placebo (14 v 21 months, P = .041). Pamidronate was safe and well tolerated during the 21 cycles of therapy. CONCLUSION: Long-term monthly infusions of pamidronate as an adjunct to chemotherapy are superior to chemotherapy alone in reducing skeletal events in stage III multiple myeloma patients, and may improve the survival of patients on salvage therapy.


Asunto(s)
Difosfonatos/administración & dosificación , Mieloma Múltiple/complicaciones , Osteólisis/prevención & control , Difosfonatos/efectos adversos , Método Doble Ciego , Esquema de Medicación , Femenino , Fracturas Espontáneas/etiología , Fracturas Espontáneas/prevención & control , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/mortalidad , Osteólisis/etiología , Pamidronato , Fracturas de la Columna Vertebral/etiología , Fracturas de la Columna Vertebral/prevención & control , Análisis de Supervivencia , Tasa de Supervivencia
10.
J Surg Oncol ; 61(4): 300-5, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8628003

RESUMEN

Palladium-103 (Pd-103) is introduced in brachytherapy procedures because of its favorable physical properties, including its low energy, rapid dose fall-off, short half-life, and total cumulative dose delivery at a higher dose rate than iodine-125 (I-125) isotope. Intraoperative brachytherapy using I-125 pellets was reported to provide significant palliation and meaningful prolongation of life in highly selected patients with unresectable carcinoma of the pancreas. After considering some of the advantages of Pd-103 over I-125, we designed a phase I-II clinical trial to assess the feasibility of intraoperative Pd-103 in unresectable carcinoma of the pancreas to study the related morbidity when combined with chemotherapy and external beam radiation, and to evaluate the impact on palliation and local control rates. Between December 1989 and December 1993, 15 patients with biopsy-proven unresectable adenocarcinoma of the pancreas were treated with interstitial Pd-103 implants during laparotomy. In 13 patients the lesion was located in the head of the pancreas, in one patient in the uncinate process, and in one patient in the body of the pancreas. The stage distribution was as follows: T1 = 2; T2 = 6, and T3 = 7. In addition, all patients underwent biliary and gastric bypass. The mean number of Pd-103 pellets was 45; the mean total activity to obtain a matched peripheral dose (MPD) of 11,000 cGy was 68.9 mCi. The mean tumor volume encompassing the MPD was 16.5 cc. All patients received postoperative external beam radiation (4,500 cGy over 4 1/2 weeks) and chemotherapy (5-fluorouracil and mitomycin C). This combined treatment, consisting of intraoperative brachytherapy using Pd-103 and postoperative external beam radiation with chemotherapy, was well tolerated in all patients. These were no treatment-related mortalities, and no serious complications, such as bleeding or fistula formation. Pain relief was obtained within 3-6 weeks in 10 out of 12 patients presenting with pain. Survival ranged from 6 to 24 months (median 10 months). The study suggests that Pd-103 can be considered an alternative to I-125 for interstitial brachytherapy for unresectable carcinoma of the pancreas. Symptom relief appeared to occur faster and complications are significantly less. However, this study did not show any improvement in the median survival rate over I-125 due to the advanced stage cancer in the majority of patients in the study.


Asunto(s)
Adenocarcinoma/radioterapia , Braquiterapia , Paladio/uso terapéutico , Neoplasias Pancreáticas/radioterapia , Radioisótopos/uso terapéutico , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/mortalidad , Anciano , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Terapia Combinada , Estudios de Factibilidad , Estudios de Seguimiento , Humanos , Paladio/administración & dosificación , Cuidados Paliativos , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/mortalidad , Estudios Prospectivos , Radioisótopos/administración & dosificación , Tasa de Supervivencia
11.
N Engl J Med ; 334(8): 488-93, 1996 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-8559201

RESUMEN

BACKGROUND: Skeletal complications are a major clinical manifestation of multiple myeloma. These complications are caused by soluble factors that stimulate osteoclasts to resorb bone. Bisphosphonates such as pamidronate inhibit osteoclastic activity and reduce bone resorption. METHODS: Patients with stage III multiple myeloma and at least one lytic lesion received either placebo or pamidronate (90 mg) as a four-hour intravenous infusion given every four weeks for nine cycles in addition to antimyeloma therapy. The patients were stratified according to whether they were receiving first-line (stratum 1) or second-line (stratum 2) antimyeloma chemotherapy at entry into the study. Skeletal events (pathologic fracture, irradiation of or surgery on bone, and spinal cord compression), hypercalcemia (symptoms or a serum calcium concentration > or = 12 mg per deciliter [3.0 mmol per liter]), bone pain, analgesic-drug use, performance status, and quality of life were assessed monthly. RESULTS: Among 392 treated patients, the efficacy of treatment could be evaluated in 196 who received pamidronate and 181 who received placebo. The proportion of patients who had any skeletal events was significantly lower in the pamidronate group (24 percent) than in the placebo group (41 percent, P < 0.001), and the reduction was evident in both stratum 1 (P = 0.04) and stratum 2 (P = 0.004). The patients who received pamidronate had significant decreases in bone pain and no deterioration in performance status and quality of life. Pamidronate was tolerated well. CONCLUSIONS: Monthly infusions of pamidronate provide significant protection against skeletal complications and improve the quality of life of patients with stage III multiple myeloma.


Asunto(s)
Difosfonatos/uso terapéutico , Mieloma Múltiple/complicaciones , Osteólisis/tratamiento farmacológico , Anciano , Supervivencia sin Enfermedad , Método Doble Ciego , Femenino , Fracturas Óseas/etiología , Fracturas Óseas/prevención & control , Humanos , Hipercalcemia/etiología , Hipercalcemia/prevención & control , Masculino , Persona de Mediana Edad , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/mortalidad , Osteólisis/etiología , Dolor/etiología , Dolor/prevención & control , Pamidronato , Compresión de la Médula Espinal/etiología , Compresión de la Médula Espinal/prevención & control , Análisis de Supervivencia , Resultado del Tratamiento
12.
Arch Intern Med ; 154(17): 1935-44, 1994 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-8074597

RESUMEN

BACKGROUND: We assessed the effects of 60-mg single doses of pamidronate disodium compared with saline alone in the treatment of cancer-associated hypercalcemia. METHODS: After pretreatment hydration, patients with corrected serum calcium concentrations of 3.0 mmol/L (12 mg/dL) or greater secondary to cancer were randomized to double-blind treatment with a single infusion of pamidronate disodium, 60 mg, over either 4 or 24 hours or continued infusions of 0.9% saline alone (n = 23 per group). Corrected serum calcium levels were measured daily for 7 days of inpatient evaluation. RESULTS: Response rates for both of the pamidronate regimens were significantly (P < .05) higher than that for saline alone. A complete response to treatment (corrected serum calcium concentration normalized) was observed for five (22%), 18 (78%), and 14 (61%) patients, respectively, who received saline alone, 4-hour infusion of pamidronate, and 24-hour infusion of pamidronate. There were no significant differences between the two pamidronate regimens. Median durations of complete response were 6, 6, and 11 days, respectively, and median times to relapse (includes complete plus partial responders and nonresponders) were 0, 7, and 7 days, respectively. Pamidronate was well tolerated as assessed by all clinical and laboratory measures, regardless of the time of infusion. CONCLUSIONS: A 4-hour infusion of pamidronate disodium, 60 mg, was as safe and effective as a 24-hour infusion, and both were superior to saline alone in lowering corrected serum calcium concentrations in patients with cancer-associated hypercalcemia.


Asunto(s)
Difosfonatos/administración & dosificación , Hipercalcemia/tratamiento farmacológico , Neoplasias/complicaciones , Adulto , Neoplasias de la Mama/complicaciones , Calcio/sangre , Calcio/orina , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Hipercalcemia/sangre , Infusiones Intravenosas , Neoplasias Pulmonares/complicaciones , Masculino , Persona de Mediana Edad , Pamidronato , Cloruro de Sodio/administración & dosificación , Resultado del Tratamiento
13.
Ir J Med Sci ; 163(8): 359-65, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8002260

RESUMEN

Changes in endothelial cell (EC) morphology occur at sites of physiological lymphocyte traffic and in areas of chronic inflammation. Previous studies have shown that EC shape changes also occur in vitro following exposure of EC monolayers to peripheral blood mononuclear cell (PBMC)-derived conditioned media (CM). In the present study, quantitative image analysis is used to define the cell of origin of the elongating factor(s), to examine changes in EC proliferation and function accompanying PBMC-induced human EC elongation and to identify the active PBMC-derived products responsible for this elongation. By separating mononuclear cells into subpopulations (macrophages, B cells and T cells) and adding conditioned media derived from these subpopulations to cultured ECs, the macrophage (M phi) is shown to be the primary cell of origin of the elongating factor(s). Furthermore, EC elongation is accompanied by both a dose-dependent decrease in cellular proliferation and an increase in prostacyclin production. These findings suggest that PBMC-induced changes in EC morphology may be associated with a shift from a proliferative state to a more secretory phase of the EC cycle. Finally, using recombinant factors it is shown that TNF alpha acting in combination with IL-1 may be the active PBMC-derived products which contribute to EC elongation.


Asunto(s)
Endotelio Vascular/citología , Sustancias de Crecimiento/fisiología , Macrófagos/metabolismo , División Celular , Células Cultivadas , Endotelio Vascular/fisiología , Humanos
14.
Int J Parasitol ; 23(8): 977-83, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8300306

RESUMEN

Adult Fasciola hepatica secrete a cysteine proteinase capable of cleaving host IgG close to the papain cleaving site. The proteinase was separated by size permeation chromatography. Gelatin-substrate polyacrylamide gel electrophoresis analysis revealed that the proteinase migrates as 6 proteolytic bands in the apparent molecular size range 60-90 kDa. Based on pH profiles of activity, inhibition studies using diethylpyrocarbonate and the diazomethylketone Z-phe-ala-CHN2, and characterising the substrate specificity of the enzymes using fluorogenic peptide substrates we have shown that the 60-90-kDa proteinases are cathepsin L-like proteinases.


Asunto(s)
Catepsinas/metabolismo , Cisteína Endopeptidasas/metabolismo , Endopeptidasas , Fasciola hepatica/enzimología , Inmunoglobulina G/metabolismo , Animales , Catepsina L , Bovinos , Inhibidores de Cisteína Proteinasa/farmacología
15.
J Biol Chem ; 268(2): 1242-51, 1993 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-8419327

RESUMEN

beta-All-trans-retinoic acid (RA)-induced endodermal differentiation of mouse F9 teratocarcinoma cells is accompanied by changes in glycoprotein glycosylation, including expression of i antigen (i.e. polylactosamine) and leukophytohemagglutinin-reactive oligosaccharides (i.e. -GlcNAc beta 1-6Man alpha 1-6-branched N-linked). We have used the F9 teratocarcinoma cells as a model to study developmental regulation of glycosyltransferase activities which are responsible for the biosynthesis of beta 1-6GlcNAc-branched N- and O-linked oligosaccharides and polylactosamine. Growth of F9 cells in the presence of 10(-6) M RA for 4 days increased core 2 GlcNAc transferase and GlcNAc transferase V activities by 13- and 6-fold, respectively, whereas the activities of GlcNAc transferase I, beta 1-3GlcNAc transferase (i), beta 1-4Gal transferase, and beta 1-3Gal transferase increased 2-4-fold. Induction of glycosyltransferase activities by RA was dose-dependent and showed a biphasic response with approximately half of the increase observed 3 days after RA treatment and the remainder occurred by day 4. PYS-2, a parietal endoderm cell line, showed levels of glycosyltransferase activities similar to those of RA-treated F9 cells. Glycosyltransferase activities in the RA-resistant F9 cell line (RA-3-10) were low and showed only a small induction by RA. These observations suggest that differentiation of F9 cells is closely associated with induction of multiple glycosyltransferase activities, with most pronounced increases in GlcNAc transferase V and 2',5'-tetradenylate (core 2) GlcNAc transferase. The increase in GlcNAc transferase V was also reflected by the 4-6-fold increase in the binding of 125I-leukophytohemagglutinin to several cellular glycoproteins, which occurred after 3 days of RA treatment. The endo-beta-galactosidase-sensitive polylactosamine content of membrane glycoproteins and, in particular, the LAMP-1 glycoprotein was markedly increased after RA treatment of F9 cells. Consistent with these observations, fucosylated polylactosamine (i.e. dimeric Lex) was also increased in RA-treated cells. Analysis of the aryl oligosaccharides produced by F9 cells cultured in the presence of aryl alpha-D-GalNAc showed that RA treatment enhanced the synthesis of disialyl core 2 O-linked oligosaccharides and increased the polylactosamine content of the aryl oligosaccharides by > 20-fold. The results suggest that differentiation of F9 cells into endoderm is closely associated with increased GlcNAc transferase V and core 2 GlcNAc transferase activities, enzymes which control the level of beta 1-6GlcNAc-branched N- and O-linked oligosaccharides, the preferred substrates for polylactosamine addition.


Asunto(s)
Amino Azúcares/biosíntesis , Diferenciación Celular/fisiología , Hexosiltransferasas/metabolismo , N-Acetilglucosaminiltransferasas/metabolismo , Polisacáridos/biosíntesis , Animales , Conformación de Carbohidratos , Secuencia de Carbohidratos , Diferenciación Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Cromatografía por Intercambio Iónico , Ensayo de Inmunoadsorción Enzimática , Cinética , Ratones , Microsomas/metabolismo , Datos de Secuencia Molecular , Oligosacáridos/biosíntesis , Oligosacáridos/aislamiento & purificación , Teratoma , Tretinoina/farmacología , Células Tumorales Cultivadas , beta-Galactosidasa/metabolismo
16.
Nucleic Acids Res ; 19(1): 85-92, 1991 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-2011514

RESUMEN

Eukaryotic expression vectors have been used successfully in viral LT-expressing cell lines (ie. COS) to clone cDNAs encoding proteins that can be detected through their bio-activity or reactivity with specific antibodies. Since Chinese hamster ovary cells (CHO) have been used extensively for the isolation and characterization of somatic cell mutants, we felt it would be an advantage to develop an expression cloning system in CHO cells. We have modified the eukaryotic expression vector CDM8 by replacing the polyoma and SV40 origins of replication with the 427bp non-coding region of the Syrian hamster papovavirus. Wild-type CHO cells and the CHO glycosylation-mutant Lec4A were transfected with plasmids bearing the early genes of either polyoma virus or hamster papovavirus in order to establish stable, LT antigen-expressing cell lines designated CHOP or CHOH, respectively. CHOP cell lines expressing polyoma LT antigen supported efficient replication of CDM8, but replicated pMH poorly. Conversely, CHOH cells expressing the hamster papovavirus LT antigen supported replication of pMH, and at a lower efficiency, CDM8. Replication of CDM8 and pMH vectors were equally efficient in selected CHOP and CHOH cell lines, respectively and comparable to that of CDM8 replication in COS-1 cells. A bacterial beta-galactosidase fusion gene inserted into the multiple cloning site of a CDM8 derivative was efficiently expressed when transiently transfected into CHOP and CHOH cells but not CHO cells since only the former supports autonomous plasmid replication. These results show that expression-cloning in CHO cells expressing either polyoma virus or hamster papovavirus LT antigens is possible using either the CDM8 or the pMH vectors, respectively.


Asunto(s)
Antígenos Transformadores de Poliomavirus/metabolismo , Clonación Molecular/métodos , Vectores Genéticos , Animales , Antígenos Transformadores de Poliomavirus/genética , Línea Celular , Cricetinae , Replicación del ADN , Femenino , Expresión Génica , Ovario , Plásmidos , Transfección
17.
Cancer Res ; 49(21): 6077-84, 1989 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-2676155

RESUMEN

Sialylated and GlcNAc beta 1-6Man alpha 1-6Man beta 1 (beta 1-6 branched) complex-type oligosaccharides linked to asparagine residues of membrane glycoproteins in metastatic murine tumor cells have been associated with efficient tumor cell metastasis. A large proportion of these oligosaccharide structures, in several unrelated malignant cell lines, have been shown to be associated with a glycoprotein termed P2B, with a molecular weight of 130,000. This glycoprotein has recently been purified from the metastatic MDAY-D2 cell line and shown to be biochemically similar to a lysosomal associated membrane glycoprotein (LAMP-1). We report here the details of a 2147 nucleotide complementary DNA encoding the entire murine P2B polypeptide which was immunoselected from a lambda gt11 expression library and sequenced. The sequence is similar to a complementary DNA coding for mouse LAMP-1 with the exception of a 5' untranslated region, a leader signal-sequence, and various insertions, deletions, and substitutions in the 3' untranslated domain. An open reading frame of 405 amino acids encodes a mature polypeptide of 382 residues with a predicted molecular weight of 42,000. P2B/LAMP-1 possesses 20 asparagine-linked glycosylation sites separated into equal halves by a central, putative hinge region and is anchored by a carboxy, membrane-spanning, domain. Topological considerations dictate that cell surface expression of P2B/LAMP-1 exposes the bulk of the glycoprotein into the extracellular compartment. Immunofluorescent staining of fibroblast cells indicated that P2B/LAMP-1 was associated with lysosomal membranes and, to a lesser degree, select surfaces of plasma membrane. An amino acid comparison of the murine sequence with its recently cloned rat, human, and chicken counterparts shows a conservation of 17 of 20 asparagine-linked glycosylation consensus sites, eight of eight cysteine residues, and other selected protein domains. The interspecies conservation of these domains suggests that they are important for the structure and function of the P2B/LAMP-1 glycoprotein. Northern analysis revealed that P2B/LAMP-1 is widely expressed in normal murine tissues and tumor cell lines. However, in two experimental models of metastasis, where changes in branching of oligosaccharides on P2B/LAMP-1 have been shown to occur, comparable levels of P2B/LAMP-1 mRNA were found in both metastatic and nonmetastatic cell lines.


Asunto(s)
Antígenos CD , Glicoproteínas de Membrana/aislamiento & purificación , Metástasis de la Neoplasia/patología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Western Blotting , Clonación Molecular , ADN de Neoplasias/genética , Técnica del Anticuerpo Fluorescente , Humanos , Leucemia Experimental/genética , Proteína 1 de la Membrana Asociada a los Lisosomas , Proteínas de Membrana de los Lisosomas , Glicoproteínas de Membrana/genética , Ratones , Datos de Secuencia Molecular , Peso Molecular , Oligosacáridos/análisis , Homología de Secuencia de Ácido Nucleico
18.
Mol Biochem Parasitol ; 35(2): 161-6, 1989 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-2770786

RESUMEN

Immature Fasciola hepatica release 11 distinct proteases when cultured in vitro for 16 h as revealed by gelatin-substrate sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Six of these proteases are active in the pH range 4.5 to 8.0. Five are acid proteases, being most active in the pH range 3.0 to 4.5. The majority of proteases released in vitro by immature flukes are also released by mature flukes; however, a 40-kDa protease released by immature flukes is a very minor protease released by mature flukes. The activity of all proteases is inhibited by leupeptin, L-trans-epoxysuccinyl-leucylamido(4-guanidino)butane, phenylmethylsulfonyl fluoride and iodoacetamide and enhanced or stabilized by the reducing agents cysteine and dithiothreitol. Therefore, all F. hepatica in vitro-released proteases identified by gelatin-substrate SDS-PAGE are thiol proteases.


Asunto(s)
Cisteína Endopeptidasas/metabolismo , Fasciola hepatica/enzimología , Animales , Cisteína/farmacología , Ditiotreitol/farmacología , Electroforesis en Gel de Poliacrilamida , Fasciola hepatica/efectos de los fármacos , Fasciola hepatica/fisiología , Técnicas In Vitro , Inhibidores de Proteasas
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