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M T Poblete

Publications and source records attributed to M T Poblete.

13 recordsLinked to original sources
PubMed1998

[Merkel cell carcinoma. Report of 4 cases].

We report four cases of Merkel cell carcinoma, a rare cutaneous neuroendocrine neoplasm with a high malignant potential. The first patient is a 90 years old male presenting with a tumor in the left superior eyelid. Surgical excision was the only treatment and seven months later, a local and regional tumoral relapse caused the death of this patient. The second patient is a 83 years old female with a tumor in her left ear. She was treated surgically and with radiotherapy, being free of disease after five years of follow up. The third patient is a 45 years old male with a tumor in the left forearm. Treatment was surgical excision of the primary tumor and axillary lymph nodes. He received post operative radiotherapy and is free of disease after three years of follow up. The last case is a 76 years old male, who was subjected only to an excisional biopsy of a lesion located in the left knee. He had a tumor relapse with inguinal and crural lymph node involvement that caused his death 12 months later.

Age Factors↗
PubMed1996

Alpha 1-antitrypsin expression in human thyroid papillary carcinoma.

Alpha 1-antitrypsin is a plasma serine protease inhibitor originally used as a marker for tumors of histiocytic origin. Our casual finding of immunoreactive alpha 1-antitrypsin in one case of thyroid papillary carcinoma led us to investigate its presence in 10 thyroid papillary carcinomas by applying immunocytochemical and immunochemical techniques to tissue sections and Western blots of tissue homogenates prepared from neoplastic tissue and from uninvolved normal areas in the vicinity of each tumor. The immunocytochemical study was performed in both thyroid tissue and metastatic regional lymph nodes. This analysis revealed immunoreactivity for alpha 1-antitrypsin in nine of the 10 cases studied. Immunoreactivity was intense in some of the cells forming the papillar and follicular structures. These cells were intermingled with completely unstained tumoral cells. In contrast to neoplastic tissue, the normal thyroid tissue present in the vicinity of each tumor showed no staining for alpha 1-antitrypsin. The electrophoretic analysis performed on homogenates prepared from both tumoral and normal thyroid tissue revealed a drastic reduction in the band corresponding to thyroglobulin in the tumoral tissue compared with normal thyroid extracts, where it represented the major protein. Western blotting and immunoprinting with a polyclonal alpha 1-antitrypsin antibody confirmed the results obtained with immunocytochemistry about the presence of this protease inhibitor in neoplastic thyroid tissue. Immunoprinting with the anti-alpha 1-antitrypsin antibody revealed an intense immunoreactive band of 53 kDa in the extracts prepared from tumoral tissue. This band had exactly the same apparent molecular mass previously described by others for alpha 1-antitrypsin purified from plasma and was identical to the molecular mass of the purified commercial standard employed.

Adolescent↗
PubMed1996

[Medullary cancer of the thyroid. Experience at the Hospital de Valdivia].

BACKGROUND: Medullary carcinoma of the thyroid is an infrequent type of thyroid tumor. AIM: To retrospectively study all cases of medullary carcinoma of the thyroid diagnosed at a regional hospital. PATIENTS AND METHODS: The charts and pathological studies of eight patients with medullary carcinoma of the thyroid, among 75 with thyroidal cancer, were reviewed. RESULTS: Solitary nodules were the presenting sign in seven patients and cachexia in one. Five patients were subjected to total thyroidectomy, five to cervical lymph node dissection and four to complementary radiotherapy. Pathological diagnosis was made with the surgical piece in seven patients and by aspiration cytology in one. Five of the eight patients are alive after 50 months of follow up as a mean, one patient with bone metastasis. CONCLUSIONS: The small sample size precludes conclusions on the prognosis and treatment of the disease.

Adolescent↗
PubMed1995

[Contemporary biopsy for diagnosis of abortion residues: preliminary experience].

The differential diagnosis between abortion and ectopic pregnancy has important clinical implications. In this report we have tested the accuracy of frozen sections in uterine curettings to identify intrauterine pregnancy. Uterine curettings with a diagnosis of products of gestation, from 104 patients were studied. In all of them plasmatic levels of B Gonadotrophin were measured. The curetting material was fixed and studied on frozen sections and on paraffin embedded tissue. A high positive relationship between frozen and embedded material was observed. The sensibility, specificity, positive and negative predictive value of the frozen section to detect chorionic villi were 90.6; 100; 100 and 74% for each of them.

Abortion, Incomplete↗
PubMed1995

[Mammary phyllodes tumor. A clinico-pathological review of 14 cases].

We report a retrospective analysis of 14 female patients, aged 20 to 62 years old, with phyllodes tumors of the breast. The tumors were located in the right breast in nine patients and their diameter ranged from 2.5 to 28 cm. Six mammographies and six needle cytological examinations were performed and aided very little to the diagnosis. The preoperative diagnosis was correct in five patients and the principal differential diagnosis was fibroadenoma. Eight patients were subjected to tumorectomy, three to simple mastectomy, one to a cleaning mastectomy, one to a modified radical mastectomy and one to a subcutaneous mastectomy. The anatomopathologic study disclosed an increased stromal growth in two patients and increased stromal cellularity in six cases. Only one case had more than five mitoses per microscopic field. Phyllodes tumors are infrequent, their diagnosis requires a high degree of clinical suspicion and they have a benign biologic behaviour.

Adult↗
PubMed1995

[Breast cancer in males. Report of 4 cases].

Breast cancer is infrequent in men. We report four men with breast cancer seen at a surgical service in Valdivia. Their presentation form, histological diagnosis and evolution are described. An updated revision of the literature is also presented.

Aged↗
PubMed1993

Localization of immunoreactive tissue kallikrein in the seromucous glands of the human and guinea-pig respiratory tree.

An immunocytochemical study focused on the cellular localization of tissue kallikrein along the human and guinea-pig respiratory tracts is reported. A strong immunoreactivity for tissue kallikrein was observed in the seromucous glands of the nasal mucosa, trachea, and bronchi. In these glands, the immunostaining was restricted to the serous component of the acinus whereas mucous cells showed no staining. Since no immunoreactivity to kininogen was observed in any of the tissue constituents of the human and guinea-pig respiratory tree, transudation of the substrate from plasma was considered to be the preferred mode of delivery of the kininogen into the bronchopulmonary interstitium and lumen. Our results provide morphological evidence for the well documented presence of tissue kallikrein in bronchial lavage fluids and support the hypothesis that kinins may be one of the more important mediators involved during acute episodes of asthma and rhinitis.

Animals↗
PubMed1991

Tissue kallikrein and kininogen in human sweat glands and psoriatic skin.

The cellular localization of immunoreactive tissue kallikrein and kininogen was studied in normal and psoriatic human skin. Immunoreactivity to both enzyme and substrate was observed in secretory granules of the dark cells in the secretory fundus (acinus) of the sweat glands. Double immunostaining revealed a segmental distribution of the two antigens. Each acinar section contained either tissue kallikrein or kininogen. However, there appeared to be a junctional zone in which both were present, but in separate dark cells. Immunoreactivity for both antigens was also observed in close apposition to the luminal microvilli of the duct cells. No specific immunostaining was seen in sebaceous glands, hair follicles, keratinocytes and other cells of the secretory unit such as myoepithelial or clear cells. In psoriatic skin there were in addition many neutrophils immunoreactive for tissue kallikrein in the epidermis and psoriatic scales. Mitogenic action of kinins may account to some extent for the characteristic accelerated turnover of epidermal cells in psoriasis and locally applied kinin antagonists may prove of value in the treatment of this disease.

Humans↗
PubMed1987

Ultrastructural characteristics of the interdigitating dendritic cell in dermatopathic lymphadenopathy of mycosis fungoides patients.

The ultrastructure of interdigitating dendritic cells in dermatopathic lymphadenopathy from patients with mycosis fungoides was investigated. The most remarkable findings were: a marked hypertrophy of the smooth endoplasmic reticulum with a peculiar concentric arrangements of the cisternae around lipid droplets, an abundance of cytoplasmic lipid droplets and the presence of paranuclear chromatoid-like bodies. It is suggested that these ultrastructural features may correspond to some unknown functional capability of the interdigitating dendritic cell.

Aged↗