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Biomedical subjects

J Costa

Publications and source records attributed to J Costa.

At least 253 records · Page 14Linked to original sources
PubMed1985

Natural history of chronic persistent hepatitis B. Relationship between hepatitis B virus replication and the course of the disease.

The status of viral replication at diagnosis and its relationship to the changes occurring during the natural history of the disease have been investigated in 26 patients with chronic persistent hepatitis (CPH) type B. Liver HBcAg and serum HBeAg were found in 73% of patients. During follow-up, serum transaminases normalized in 13/17 HBeAg-positive patients 1-6 years after diagnosis and 11 of them developed anti-HBe. HBe seroconversion was closely preceded by a transient elevation of transaminases in 5 patients in whom a repeated liver biopsy showed prominent lobular hepatitis and marked reduction of liver HBcAg. Such changes resulted in long-lasting biochemical normalization but only 1 patient became HBsAg-negative. These observations indicate that prolonged viral replication occurs in type B CPH. Termination of replication frequently implies a transient worsening caused by lysis of HBcAg-containing hepatocytes which leads to inactivation of the disease and to development of a healthy HBsAg carrier state.

Adolescent↗
PubMed1985

Results of multimodality therapy of resectable soft-tissue sarcomas of the retroperitoneum.

Thirty-seven patients with resectable retroperitoneal sarcomas were studied prospectively to determine the efficacy of aggressive multimodality treatments. No patients was lost to follow-up, which ranged from 11 to 85 months (median 29 months). All patients received radiotherapy and some received postoperative chemotherapy (doxorubicin, cyclophosphamide, and high-dose methotrexate). A subset of 15 patients were entered into a prospective, randomized study testing the efficacy of adjuvant chemotherapy (eight received chemotherapy; seven did not). Two-year actuarial survival rates were inferior in the chemotherapy arm (100% versus 47%; p = 0.06), but the small number of patients precluded drawing definitive conclusions from this randomized study alone. Among the entire 37 patients (21 received chemotherapy; 16 did not) the actuarial 3-year survival rate was 43% and appeared unaffected by chemotherapy. Two patients suffered doxorubicin infiltration, three sustained cardiac toxicity, two developed cyclophosphamide-induced cystitis, and three withstood transient, severe bone marrow suppression. Eight patients suffered severe radiation enteritis, and one patient died after bowel resection for this problem. Thus the chemotherapy regimen we administered did not appear to improve survival but was associated with major morbidity. Radiotherapy was also associated with major complications, and since all patients received radiotherapy, it remains to be established if this modality is beneficial in improving survival.

Actuarial Analysis↗
PubMed1985

Pachydermodactyly.

Pachydermodactyly is a rare distinct form of fibromatosis characterized by dense fibrosis and fibroblastic proliferation around one or more proximal interphalangeal joints. Pachydermodactyly affects the appositional and dorsal aspects of proximal digits II-V. The lateral aspects of the index fingers, the medial aspect of the fifth digits, and the thumbs are usually unaffected. A typical patient was a young adult man with a long history of idiopathic asymptomatic swelling in the fingers. Skin biopsy specimens obtained from three patients with pachydermodactyly showed marked thickening of the dermis with extension of collagenous fibers into the subcutaneous tissues. There was poor demarcation between the papillary and reticular dermis. The cytology of the fibroblasts appeared benign. Isolation of collagen from the involved sites revealed collagen Types I, III, and V in a pattern typical of fibromatoses; i.e. increased Types III and V. Compared with the collagen profile of normal reticular dermis, increased numbers of fine-diameter collagen fibers were notable in electron micrographs.

Adolescent↗
PubMed1984

The grading of soft tissue sarcomas. Results of a clinicohistopathologic correlation in a series of 163 cases.

A multidisciplinary study of 163 patients treated at the NCI for soft tissue sarcomas allowed the correlation of a number of histologic features (histologic type, mitosis, necrosis, pleomorphism, cellularity, and matrix) of the primary lesion to time to recurrence and overall survival of the patients. The results of the stratified analyses show that necrosis is the single best histopathologic parameter to predict the time to recurrence (P = 0.025) and the overall survival of the patients (P = 0.002). Necrosis in the primary lesion is also of value in predicting survival after the first recurrence has taken place (P = 0.001). The value of necrosis in the primary lesions predicting the clinical course after recurrence appears to be independent of age, sex, location, and size of the tumor. The authors propose a grading system based on histologic typing and histologic parameters to identify a group of lesions with minimal metastatic potential (Grade 1), and on the use of necrosis to distinguish between aggressive lesions with good patient survival (Grade 2) and aggressive lesions with poor patient survival (Grade 3).

Adolescent↗
PubMed1984

Hepatocellular carcinoma with carcinoid features.

A primary hepatic neoplasm with histologic features suggestive of both hepatocellular carcinoma and carcinoid tumor was studied by light microscopy, electron microscopy, and immunocytochemistry. These methods revealed areas of hepatocellular carcinoma, areas of carcinoid tumor, and mixed areas within the same cell. This case provides one more example of the coexistence of carcinoma and carcinoid in the same neoplasm and thereby supports the hypothesis that a malignantly transformed stem cell can differentiate in both epithelial and amine precursor uptake and decarboxylation (APUD) directions.

APUD Cells↗
PubMed1984

Evidence that renal prostaglandins are involved in renal water metabolism in cirrhosis.

Plasma antidiuretic hormone (ADH) and urinary prostaglandin E2 excretion (UPGE2V) were measured in basal conditions, after water restriction, and after water-loading in 10 normal subjects (free water clearance after the water load, CH2O, 9.6 +/- 0.8 ml/min) and in 27 patients with cirrhosis and ascites (13 with a positive CH2O: 3.6 +/- 0.5; 14 with a negative CH2O: -0.37 +/- 0.007). Plasma ADH and UPGE2V were significantly increased in patients with a positive CH2O as compared with normal subjects. Patients with a negative CH2O showed a significantly higher plasma ADH and a lower UPGE2V and GFR than did normal subjects and patients with the positive CH2O. In 18 additional subjects (6 normal and 12 with cirrhosis, ascites, and a positive CH2O) submitted to a sustained water overload, the i.v. administration of 450 mg of lysine acetylsalicylate (LAS) induced a marked reduction of UPGE2V, but it had no effect on plasma ADH. LAS did not alter GFR and CH2O in normal subjects; however, it reduced CH2O in all the 12 patients (from 5.1 +/- 0.4 to 0.6 +/- 0.3) and the GFR in only 6 of these patients. These results suggest (a) that renal PGE2 plays an important role in the maintenance of water excretion in cirrhosis with ascites, and (b) that impaired ability to dilute the urine in cirrhosis may be a consequence of the simultaneous occurrence of impaired renal hemodynamics, nonostomic hypersecretion of ADH, and reduced renal production of PGE2.

Arginine Vasopressin↗
PubMed1983

Prospective randomized evaluation of adjuvant chemotherapy in adults with soft tissue sarcomas of the extremities.

Sixty-five patients with high-grade soft tissue sarcomas of the extremities were treated in a prospective randomized trial evaluating the efficacy of adjuvant chemotherapy with doxorubicin, cyclophosphamide, and high-dose methotrexate. Local therapy was administered using either amputation or wide local resection plus radiation therapy and the chemotherapy was begun in the immediate postoperative period. Actuarial analysis with median follow-up of 653 days revealed an advantage in continuous disease-free and overall survival in the patient group receiving chemotherapy (P = 0.0008 and P = 0.04, respectively, one-sided Mantel-Haenszel test). The continuous disease-free survival at three years is 92% in the chemotherapy group compared to 60% in the no chemotherapy group. Overall survival is 95% and 74% in these two patient groups. Fifty-eight percent of patients had limb-sparing surgery plus radiation therapy and 42% underwent amputation. In both treatment subgroups analyzed separately, chemotherapy resulted in an improvement in disease-free survival compared to randomized controls not receiving chemotherapy (P = 0.006 and P = 0.04 for groups receiving amputation and limb sparing, respectively). There were no local failures in the patients receiving chemotherapy and two local failures in the no chemotherapy group. The results of this trial confirm the historically controlled pilot trial performed in 26 patients between 1975 and 1977. A current update of the patients in the pilot trial, with a minimum four-year follow-up, reveals an improvement in disease-free and overall survival due to chemotherapy (P less than 0.002). Analysis of the previous pilot trial indicates that only few recurrences are seen beyond three years. Thus, it appears that adjuvant chemotherapy should be a part of the treatment adult patients with soft tissue sarcomas of the extremities.

Adult↗
PubMed1983

Malignant lymphoma and erythrophagocytosis simulating malignant histiocytosis.

Six patients with malignant lymphoma are described, in whom a syndrome that mimicked malignant histiocytosis clinically and pathologically developed as a terminal event. The clinical course was characterized by hepatosplenomegaly, fever, and a rapid fall in all hematologic counts. Survival from onset of this syndrome was less than six weeks. Pathologically, activation of benign histiocytes with marked erythrophagocytosis was seen throughout the reticuloendothelial system. Disseminated lymphoma was also evident but was grossly and microscopically segregated from the erythrophagocytic process. Immunologic and cytochemical studies in two cases indicated the lymphomas to be of peripheral T cell origin, whereas the phagocytic cells had markers characteristic of histiocytes. A likely mechanism for this syndrome is the production of lymphokines (macrophage-activating factors) by neoplastic T lymphocytes.

Adolescent↗
PubMed1983

Immunoreactivity of paraffin-embedded normal tissues and mesenchymal tumors for smooth muscle myosin.

Immunohistochemical study of smooth muscle myosin, a protein distinct from skeletal, cardiac, or nonmyogenous myosins in paraffin-embedded normal tissues and benign and malignant mesenchymal tumors revealed its strong expression in normal smooth muscle, capillary endothelium, and pericytes. All benign smooth muscle tumors with exception of gastric leiomyomas and few other leiomyomas of the gastrointestinal tract displayed strong or moderate immunoreactivity. On the other hand, strong or moderate immunoreactivity was detected in only eight of 28 spindle-cell leiomyosarcomas, as well as in 13 out of 27 malignant fibrous histiocytomas and three out of nine malignant hemangiopericytomas, while epithelioid leiomyosarcomas, fibrosarcomas, malignant schwannomas, and synovial sarcomas were negative or only weakly positive. Our results demonstrate that, while smooth muscle myosin is a very good marker of normal smooth muscle and benign smooth muscle tumors, it is expressed in diagnostically significant amounts in less than a third of spindle-cell leiomyosarcomas and none of the studied epithelioid leiomyosarcomas.

Female↗
PubMed1983

Extraskeletal Ewing's sarcoma: results of combined modality treatment.

Eleven patients with extraskeletal Ewing's sarcoma (EES) were treated with combined modality therapy at the National Cancer Institute. The diagnosis of EES was reserved for lesions that were identical to Ewing's sarcoma of bone by light and electron microscopy. Diagnostic work-up to rule out a skeletal primary included bone scan, localized views of adjacent bone, and bone tomography. Seven patients presented with an extremity primary and four patients had a truncal primary. No patients had evidence of metastases at presentation. Patients were treated with combined modality therapy consisting of high-dose local irradiation and vincristine, actinomycin D, and cyclophosphamide chemotherapy following a biopsy or local excision. No attempt was made to excise widely the primary tumor mass. Gross tumors generally responded rapidly to the combined modality treatment. Of 11 patients, seven (64%) remain disease free, with a follow-up of three to seven years from completion of therapy. Long-term local control was established in nine of 11 patients (82%). Autopsy findings on two patients with local failure showed no tumor involvement of adjacent bone. Attempts at gross resections by radical surgical procedures do not routinely appear to be necessary in light of the high local control rates with high-dose irradiation.

Adolescent↗
PubMed1983

[Specificity of the determination of urinary kallikrein activity using an amidolytic assay].

The specificity of a method for the determination of the urinary kallikrein activity based on the amidolytic hydrolysis of the synthetic substrate H-D-valyl-leucyl-arginine-p-nitroanilide has been studied. Results show a good specificity for kallikrein. The amidolytic activity was totally inhibited by aprotinin. The urinary amidolytic activity showed identical dependence on changes in the ionic strength and pH of the incubation medium as the highly purified kallikrein. The sensitivity of the assay was 0.6 nkat/l. The intra-assay coefficient of variation was 4% and the inter-assay coefficient of variation was 10%. The percentage of recovery was between 100 and 110% indicating that no activators or inhibitors of the kallikrein activity on this substrate were present in the urinary samples. Values obtained in presumably healthy subjects were 0.14 +/- 0.08 pkat/s in man (range: 0.05 - 0.27 pkat/s) and 0.49 +/- 0.11 pkat/s in rat (range: 0.35 - 0.58 pkat/s).

Adult↗
PubMed1983

Immunohistochemical study of alveolar and embryonal rhabdomyosarcoma.

Paraffin-embedded sections of 11 alveolar and 12 embryonal rhabdomyosarcomas, 12 lymphomas, five neuroblastomas, five extraskeletal neoplasms resembling Ewing's sarcoma, and six epithelial tumors were tested for immunoreactivity against myosin, myoglobin, and isozymes BB and MM of creatine kinase with a peroxidase-antiperoxidase method. Of the 23 cases of rhabdomyosarcomas 17 were positive for at least three of the antigenic determinants. In contrast, the other investigated tumors were consistently negative for all markers, with the exception of breast and prostatic carcinomas. Our results establish that the presence of three or four of the above markers in a tumor is strongly suggestive of a rhabdomyosarcoma and helpful in the distinction of alveolar and embryonal rhabdomyosarcomas from lymphomas, neuroblastomas, and extraskeletal neoplasms resembling Ewing's sarcoma.

Adolescent↗
PubMed1982

Intra-abdominal carcinomatosis after prophylactic oophorectomy in ovarian-cancer-prone families.

Prophylactic oophorectomy was performed in 28 female members of 16 families at high risk of ovarian carcinoma. 3 of these women subsequently developed disseminated intra-abdominal malignancy; there was uncertainty about the primary site despite extensive investigation. These tumours were indistinguishable histopathologically from ovarian carcinoma. It would seem that in cancer-prone families the susceptible tissue is not limited to the ovary, but includes other derivatives of the coelomic epithelium, from which primary peritoneal neoplasms may arise.

Abdominal Neoplasms↗