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1.
Ann Surg Oncol ; 16(9): 2579-86, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19557478

RESUMEN

BACKGROUND: Decreased performance status, comorbidities, and disease natural history may erode enthusiasm for soft tissue sarcoma (STS) resection in elderly patients. Consequently, we evaluated the outcome of elderly patients amenable to complete surgical resection treated at a single institution. METHODS: Prospectively accrued data were used to identify patients with primary STS age >or=65 years (n = 325) who underwent complete macroscopic resection at our institution (1996-2007). Univariable and multivariable analyses were performed to identify prognostic factors. RESULTS: Median age at presentation was 72 years; 179 patients (55.1%) had associated comorbidities with an ASA score of >or=3. Extremity was the most common site (57.1%; n = 186), undifferentiated pleomorphic sarcoma the most common histology (60.4%; n = 197); 232 (71.2%) were high grade, 222 (68.3%) were >5 cm. Thirty-day postoperative mortality was 0.9% (n = 3); overall complication rate was 30.7% (n = 100), and mean postoperative hospital stay was 9 days (range, 1-84). Estimated median survival was 96 months, 5-year disease-specific survival (DSS) was 63%. Multivariable analysis identified age >or=75 year (HR = 2.03), tumor size: 5-15 vs <5 cm (HR = 3.54), or >15 vs <5 cm (HR = 10.33), and high-grade (HR = 5.53) as significant independent adverse prognostic factors. Compared with patients aged 65-74 years, older patients had more high grade tumors (P = .04), received chemotherapy less often (P < .0001), developed different patterns of recurrence (P < .05), and exhibited a shorter median survival (70 months; P = .05). CONCLUSIONS: Properly selected elderly patients can safely undergo extensive STS resections. Until more effective therapies become available, surgery in the elderly is indicated and remains the best means for STS control.


Asunto(s)
Sarcoma/cirugía , Factores de Edad , Anciano , Anciano de 80 o más Años , Comorbilidad , Femenino , Humanos , Masculino , Estadificación de Neoplasias , Pronóstico , Estudios Prospectivos , Sarcoma/patología , Tasa de Supervivencia , Resultado del Tratamiento
2.
Anticancer Res ; 21(4A): 2287-91, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11724284

RESUMEN

BACKGROUND: Various fragments of the fibrinolytic protein plasminogen can act as antiangiogenic factors and inhibit the growth of primary and metastatic tumors in mice. Plasminogen-related gene-B encodes a putative 9 kDa protein virtually identical to the plasminogen N-terminal activation peptide, a 77-amino acid motif that is liberated from the parent plasminogen molecule during conversion to the serine proteinase plasmin. Previous data have documented enhanced transcription of plasminogen-related gene-B in neoplastic tissues. MATERIALS AND METHODS: We have tested the effects of recombinant versions of plasminogen-related protein-B and the plasminogen N-terminal activation peptide on the growth of tumors in mice, employing murine tumor cell lines implanted subcutaneously. RESULTS: The recombinant plasminogen-related protein-B significantly inhibited the growth of primary tumors in mice, while recombinant plasminogen N-terminal activation peptide elicited only a slight inhibition of tumor growth. CONCLUSION: These data suggest that plasminogen-related protein-B may have utility as a novel cancer therapeutic.


Asunto(s)
Antineoplásicos/farmacología , Plasminógeno/farmacología , Inhibidores de la Angiogénesis/farmacología , Animales , Carcinoma Pulmonar de Lewis/tratamiento farmacológico , Carcinoma Pulmonar de Lewis/patología , División Celular/efectos de los fármacos , Fibrosarcoma/tratamiento farmacológico , Fibrosarcoma/patología , Inhibidores de Crecimiento/farmacología , Masculino , Ratones , Ratones Endogámicos C57BL , Fragmentos de Péptidos/farmacología , Proteínas Recombinantes/farmacología
3.
J Bone Joint Surg Am ; 82(8): 1083-8, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10954096

RESUMEN

BACKGROUND: Parosteal osteosarcoma is a low-grade malignant bone tumor that arises from the surface of the metaphysis of long bones. Parosteal osteosarcoma is usually well differentiated and displays a low propensity to metastasize. Wide resection of a parosteal osteosarcoma has been shown to provide a relatively risk-free method of preventing local recurrence. We propose a new method of resection of parosteal osteosarcomas located in the popliteal paraosseous space of the distal part of the femur. This method involves resection of the mass through separate medial and lateral incisions, which allows for wide margins yet limits the amount of dissection of the soft tissues and the neurovascular bundle. METHODS: Six patients with parosteal osteosarcoma located on the posterior aspect of the distal part of the femur underwent resection of the lesion and reconstruction with a posterior hemicortical allograft through dual medial and lateral incisions. The patients were evaluated with regard to pain, postoperative function, union of the allograft (osteosynthesis), and the prevalence of local recurrence. RESULTS: The average time until the last follow-up assessment was 4.3 years. No metastases developed, and there were no local recurrences. All patients were free of disease at the last follow-up evaluation. Postoperatively, the average range of motion of the knee was 0 to 122 degrees. Five of the six patients were free of pain at the time of the latest follow-up. Five of the six patients returned to their preoperative active functional status. CONCLUSIONS: We recommend resection of a parosteal osteosarcoma located on the posterior surface of the femur through separate medial and lateral incisions. This approach provides minimal dissection of the neurovascular bundle but ample exposure for reconstruction with a hemicortical allograft.


Asunto(s)
Neoplasias Femorales/cirugía , Osteosarcoma Yuxtacortical/cirugía , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Procedimientos Ortopédicos
4.
Eur J Biochem ; 259(3): 618-25, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10092845

RESUMEN

The cDNA corresponding to exons 2-4 of the processed human plasminogen (Pgn) gene, encoding the N-terminal peptide domain (NTP), has been cloned, expressed in Escherichia coli as a recombinant protein (r-NTP) containing a hexahistidine tag, and refolded to the native structure that contains two internal cystine bridges. RNA expression of the two Pgn-related genes, PRG A and PRG B, that potentially encode 9-kDa polypeptides having extensive similarity to the NTP has been investigated. Using RNA-based PCR with liver RNA as template, we demonstrate that PRG A encodes a detectable mRNA species. PRG A and PRG B have been found to be transcribed in the liver and yield virtually identical mRNAs. Neither of the PRGs are expressed in a variety of other normal tissues, as determined by Northern blot analysis. Factor-Xa digestion of the tagged r-NTP yields cleavage products which indicates that the expressed r-NTP domain of Pgn is endowed with a flexible conformation. Recombinant PRG B protein (r-PRG B) fused to a hexahistidine tag was purified and analyzed for structural integrity. Preliminary 1H-NMR spectroscopic data for r-NTP and r-PRG B indicate relatively fast amide 1H-2H exchange in 2H2O and close conformational characteristics for the two homologous polypeptides. Far ultraviolet-CD spectra for r-NTP and r-PRG B at pH 7.0 indicate similar defined secondary structure content for both domains, with 13-17% alpha-helix and 24-27% antiparallel beta-sheet. The fact that two transcriptionally active genes encode almost identical polypeptides supports the hypothesis that the Pgn NTP, together with the putative polypeptides encoded by the PRGs, may serve an important function, such as controlling the conformation of Pgn and thus its susceptibility to tissue activators.


Asunto(s)
Plasminógeno/genética , Secuencia de Aminoácidos , Secuencia de Bases , Dicroismo Circular , Clonación Molecular , Escherichia coli/genética , Factor Xa/metabolismo , Humanos , Hígado/metabolismo , Espectroscopía de Resonancia Magnética , Conformación Molecular , Datos de Secuencia Molecular , Fragmentos de Péptidos/química , Fragmentos de Péptidos/genética , Plasminógeno/química , Pliegue de Proteína , Estructura Secundaria de Proteína , ARN Mensajero/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Análisis de Secuencia de ADN , Transcripción Genética/genética
5.
Psychopharmacology (Berl) ; 103(3): 407-14, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-2057541

RESUMEN

Noradrenergic neuronal hyperactivity following chronic morphine administration has been postulated to cause withdrawal signs and symptoms. Suppression of this hyperactivity, for example, by clonidine attenuates withdrawal. It might follow, therefore, that the prevention of suppression of noradrenergic systems during chronic morphine administration might diminish hyperactivity and prevent withdrawal. If the normalization of noradrenergic activity during opioid administration did not also suppress analgesia, it might be of medical and theoretical interest. To test this hypothesis, we gave the alpha-2-antagonist yohimbine to rats in order to increase noradrenergic activity during morphine treatment and then subsequently precipitated morphine withdrawal with naloxone. Six groups were examined: saline controls (N = 11), morphine (N = 11), morphine + 2.0 mg/kg/day yohimbine (N = 15), morphine + 3.0 mg/kg/day yohimbine (N = 5), 2.0 mg/kg/day yohimbine (N = 11) and 3.0 mg/kg/day yohimbine (N = 5). Subjects received 75 mg morphine pellets implanted on day 1,4 and 6 of the treatment or sham implantation. Yohimbine was delivered throughout the morphine treatment by subcutaneously implanted osmotic pumps. On day 7, all subjects were given 1.0 mg/kg naloxone and rated for behavioral signs of withdrawal. Analgesia was measured by observing tail flick latencies (TFL) before and after chronic drug treatments. Naloxone-precipitated withdrawal was characterized by irritability, ptosis, penile erection, diarrhea, rhinorrhea, abnormal posture, wet-dog shakes, jumping, and teeth chattering, none of which were observed in groups receiving only saline or yohimbine. Withdrawal behavior was attenuated in a dose-dependent manner when yohimbine was administered during morphine treatment but analgesia was not attenuated.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Analgésicos , Morfina/farmacología , Naloxona/farmacología , Síndrome de Abstinencia a Sustancias/psicología , Yohimbina/farmacología , Animales , Conducta Animal/efectos de los fármacos , Implantes de Medicamentos , Masculino , Morfina/administración & dosificación , Ratas , Ratas Endogámicas , Tiempo de Reacción/efectos de los fármacos , Yohimbina/administración & dosificación
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