Biomedical subjects

I Péter

Publications and source records attributed to I Péter.

At least 19 recordsLinked to original sources

PubMed2006

Hypercalcitoninemia in a patient with a recurrent goitre and insulinoma: a case report.

Serum calcitonin has become a very sensitive and specific marker for medullary thyroid carcinoma that should be determined in patients with nodular thyroid disease. However, a few earlier reports indicated that tumors other than medullary thyroid carcinoma including insulinomas arising from pancreatic islet cells may also produce calcitonin. Of the few cases of calcitonin-producing insulinomas previously reported, most had incomplete data or lack of documentation of the association between raised serum calcitonin concentration and immunohistochemical detection of calcitonin in pancreatic islet cell tumors. In this paper we are reporting a 54-year-old woman with a history of partial thyroidectomy for multinodular goitre at the age of 50 yrs, she was evaluated for a 2-months history of fasting hypoglycemia (plasma glucose 1.9 mmol/L during a supervised fast), raised serum insulin (at the time of hypoglycemia 88.8 microU/ml; normal, 5 - 35 microU/ml) and C-peptide levels (at the time of hypoglycemia 6.1 ng/ml; normal, 1.37 - 3.51 ng/ml), markedly increased serum calcitonin concentration (481 pg/ml; normal, < 9.9 pg/ml), and an enlarged residual thyroid gland. Aspiration biopsy of the thyroid was negative for parafollicular C-cell hyperplasia or medullary thyroid carcinoma. Abdominal ultrasound and CT scan revealed a tumor in the head of the pancreas, which was surgically removed. Histopathological evaluation of the pancreatic tumor showed typical features of a neuroendocrine neoplasm with strong immunostaining for both insulin and calcitonin. After removal of the pancreatic tumor, clinical symptoms resolved and biochemical markers normalized (serum insulin, 14.9 microU/ml; C-peptide, 3.0 ng/ml; calcitonin, 2.9 pg/ml) confirming the causal relationship between insulinoma and markedly increased serum calcitonin levels.

Calcitonin↗

PubMed2003

FDG PET imaging in hereditary thyroid cancer.

AIM: To report the role of different imaging methods in staging individuals with multiple endocrine neoplasia 2A (MEN2A) or familial medullary thyroid carcinoma (FMTC). MATERIAL AND METHODS: Fourteen newly diagnosed gene carriers underwent cervical ultrasound scanning (US), cervical and mediastinal CT, MRI and whole-body meta-[131I]iodobenzylguanidine (MIBG) scintigraphy and [18F]fluorodeoxyglucose (FDG) PET scanning. RESULTS: US identified seven true primary cancer. CT and MRI located only tumors > or =5 mm in diameter. MIBG scintigraphy and FDG PET could not identify MTC foci within the thyroid. Whole-body FDG PET identified two true-positive and one false-positive lymph node metastases. MIBG scintigraphy did not identify lymph node metastases. Total thyroidectomy was performed in 12 cases, and subtotal thyroidectomy in two subjects. CONCLUSIONS: Whole-body FDG PET and cervical US help stage individuals carrying mutant genes verifying MEN2A or FMTC.

Adolescent↗

PubMed2001

bcl2, p53 and bax in thyroid tumors and their relation to apoptosis.

Twenty five thyroid tumors were investigated by immunohistochemistry for the presence of apoptosis, expression of p53, bax and bcl2. In nine adenomas (average age 40) the rate of p53 positive cells was 5.7%, while it was 13.3% for bax and 41.7% for bcl2 in the tumor cells. In six follicular carcinomas (average age 56) p53 positivity was obtained for 71.1%, while bax and bcl2 positivity constituted 3.4% and 2.5%, respectively. In ten papillary adenocarcinomas (average age 42) p53 was positive in 39.6%, but bax and bcl2 were positive in 3.4% and 3% of the tumor cells, respectively. Almost no signs of spontaneous apoptosis were found in any of the cases. Determination of p53, bax and bcl2 ratio in thyroid tumors may contribute to the differentiation between follicular adenomas and carcinomas.

Adenocarcinoma, Follicular↗

PubMed1999

[The role of intraoperative gamma-probe-guided sentinel lymph node biopsy in the treatment of malignant melanoma and breast cancer].

In the treatment of malignant tumors regional lymphadenectomy is used for two purposes. It is used partly for staging the regional lymph nodes which is a significant and independent prognostic factor and determines the need for adjuvant oncologic treatment and partly for achieving locoregional disease control. Removal of tumor-free lymph nodes by regional lymph node clearance is unnecessary according to our current knowledge. Since the sensitivity and specificity of non-invasive clinical examinations are insufficient in predicting the nodal status the histological study of the regional lymph nodes cannot be abandoned. A new and minimally invasive surgical procedure, the mapping and removal of the first tumor draining lymph node, the sentinel node provides the possibility of pathological nodal staging without performing formal lymphadenectomy. Mapping of the sentinel node can be performed by the use of a radioisotope and intraoperative hand-held gamma-probe or a vital blue dye or a combination of these two. This latter method was used by the authors in 73 patients (25 with malignant melanoma and 48 with breast cancer). Sentinel lymph node biopsy was performed successfully in 92% of patients with melanoma and 90% of patients with breast cancer. In three breast cancer patients the sentinel node inaccurately predicted the axillary status as negative, but is was in 93% accurate in predicting the histologic nodal state. According to our preliminary experiences intraoperative gamma-probe guided sentinel lymph node biopsy is considered a feasible procedure in both malignant melanoma and breast cancer. More experiences are needed before introducing this method in the routine clinical practice.

Biopsy↗

PubMed1999

[Amyloid goiter].

Amyloid goitre is at an extremely rare occurrence. Authors review the origin of disease and its symptoms, diagnostic and therapeutic tools. The disease may be due to either primary or secondary systemic or local amyloidosis. Diagnosis may be made even before surgery on anamnestic data, on very rapid growth of thyroid glands, on diffuse appearance, on other symptoms of systemic amyloidosis, on findings of iconographic procedures and on detection of amyloid in aspirates. Final diagnosis is based on histology. Surgical therapy is aiming at avoidance of the existing and the threatening consequences of expanding mass. The outcome is independent from thyroid surgery, it is related to other manifestations of amyloidosis. Concerning with the present case the chronic superior vena cava syndrome and chylous pleural effusion as first described symptoms and asymptomatic hyperthyroxinaemia is emphasised. Neither other organ involvement, nor primary amyloidogenous molecula was found during the 18 months follow up, so patient has secondary and localised amyloidosis.

Amyloidosis↗

PubMed1999

Gonadotropin-releasing hormone analogue conjugates with strong selective antitumor activity.

Conjugation of gonadotropin-releasing hormone (GnRH) analogues GnRH-III, MI-1544, and MI-1892 through lysyl side chains and a tetrapeptide spacer, Gly-Phe-Leu-Gly (X) to a copolymer, poly(N-vinylpyrrolidone-co-maleic acid) (P) caused increased antiproliferative activity toward MCF-7 and MDA-MB-231 breast, PC3 and LNCaP prostate, and Ishikawa endometrial cancer cell lines in culture and against tumor development by xenografts of the breast cancer cells in immunodeficient mice. MCF-7 cells treated with P-X-1544 and P-X-1892 displayed characteristic signs of apoptosis, including vacuoles in the cytoplasm, rounding up, apoptotic bodies, bleb formation, and DNA fragmentation. Conjugates, but not free peptides, inhibited cdc25 phosphatase and caused accumulation of Ishikawa and PC3 cells in the G2/M phase of the cell cycle after 24 h at lower doses and in the G1 and G2 phases after 48 h. Since P-X-peptides appear to be internalized, the increased cytotoxicity of the conjugates is attributed to protection of peptides from proteolysis, enhanced interaction of the peptides with the GnRH receptors, and/or internalization of P-X-peptide receptor complexes so that P can exert toxic effects inside, possibly by inhibiting enzymes involved in the cell cycle. The additional specificity of P-X-peptides compared with free peptides for direct antiproliferative effects on the cancer cells but not for interactions in the pituitary indicates the therapeutic potential of the conjugates.

Animals↗

PubMed1998

[Malignant schwannoma of the breast].

Authors describe a malignant solitary schwannoma observed in the left breast of a 67-year old woman. Eight months after tumour removal the patient is symptom and complaint-free. The present case of breast schwannoma is the first clinical observation in the national and the 14th one in the world literature.

Aged↗

PubMed1997

New aspects in the pathology of the preneoplastic lesions of the larynx.

In our 5-year biopsy study (1991 95) 51% of keratoses and 16% of adult-onset papillomas contained certain degrees of dysplasia. Koilocytosis associated with HPV infection was prominent in papillomas and the majority of keratosis but negligible in cancer. Using mouse monoclonal antibody against human p53 we detected by immunohistochemistry mutated p53 overexpression not only in cancer but in some cases of keratoses and papillomas. CD44 is a multifunctional integral cell membrane glycoprotein and is found in many mesenchymal, epithelial and tumor cells. CD44 has a great number of splice variants, isoforms supposedly implicated in development, progression and metastasis formation of tumors. Using monoclonal antibody to CD44 our study suggests that the expression of pan CD44 at successive stages of human laryngeal carcinogenesis gives preliminary information about the selection advantage to the tumor cells.

Adult↗

PubMed1994

[Pharmacology of colchicine and its use in dermatology].

This study provides a summary about an old drug, colchicine, which has been used in medicine for two thousand years. It emphasizes the importance of this agent in the treatment of dermatologic diseases, especially in vasculitis. One of the aims of the study to spread the application of colchicine in the therapeutic management.

Colchicine↗

PubMed1993

Establishment, characterization and drug sensitivity of a new anaplastic thyroid carcinoma cell line (BHT-101).

A thyroid carcinoma cell line, BHT-101, has been established in vitro from a metastatic lymph node deposit in a female patient with a non-hormone producing anaplastic, partly thyroglobulin- and thyroxine (T4)-positive papillary thyroid cancer. The cell population is heterogeneous, containing epithelial-like and fibroblast-like cells, and has a doubling time of 24 h. The cell line is polyploid with hypertetraploid predominance and the karyotype showed trisomies, tetrasomies, pentasomies as well as many marker chromosomes. The majority of the cells are negative or weakly positive for thyroglobulin and thyroxine and estrogen and progesterone receptors are present in the cells. BHT-101 cells produce tumours when injected into immunosuppressed CBA/Ca mice. The cells are sensitive to adriamycin, methotrexate and tamoxifen but not to methimazole (Favistan). The epithelial-like clone 1 and the fibroblast-like clone 3, isolated from the parental line, differed in drug sensitivity. This new cell line is suitable for studying the biology of thyroid carcinoma and for parallel in vivo and in vitro studies of drug activity against thyroid cancer.

Animals↗

PubMed1991

Follicular cancer of the thyroid gland.

Between 1965 and 1987 the authors studied the survival of 169 patients (130 females, 39 males) suffering from follicular thyroid cancer. It is established that the factors favorably influencing the course of the disease are as follows: age below 40 years, female sex, tumor location inside the thyroid capsule. Radical surgery does not affect the survival, though it prolongs the time to the onset of metastases. In women below 40 years of age, iodine treatment performed within 1.5 months following surgery does not increase the effectiveness; therefore, its routine application is not recommended. In case of local metastases associated with hindered swallowing or respiration, external beam radiotherapy is indicated. Hormone substitution ensuring TSH restriction results in improved prognosis.

Adenocarcinoma↗

PubMed1991

Genotypic and phenotypic changes of a mouse lymphoma during long-term cultivation.

NK/Ly mouse lymphoma ascites cells were explanted and established in culture. The cells grew in monolayer and showed fibroblast-like morphology. The original NK/Ly cells contained one large metacentric marker chromosome, while the in vitro growing cells had two metacentrics in the early passages. These so-called bi-armed chromosomes were growing in number, up to seven, along with the number of subcultures. No tumour "take" was observed when the cells were given into mice intraperitoneally. However, a solid tumour developed following injection of cells into the leg muscle. The histological picture of this solid tumour was anaplastic sarcoma. It is concluded that the accumulation of bi-armed chromosomes, which were formed either by anaphase bridges, or by centric fusion of telocentric chromosomes, led to a profound alteration of lymphoma resulting a phenotype of anaplastic sarcoma.

Animals↗

PubMed1990

Lipid-rich cell thyroid adenoma: histopathology with comparative lipid analysis.

A second case of the unique lipid-rich cell thyroid adenoma is described complemented by detailed lipid analysis. New observations were made. The cytoplasm of the tumour cells contained scattered, aggregated sudanophil crystals; under polarized light the frozen, unstained sections exhibited numerous birefringent lipid crystals; electron microscopy provided further evidence that the clear cell appearance was due to intracellular lipid droplets with scanty glycogen particles. Comparative lipid analysis by thin layer chromatography and high-pressure liquid chromatography (HPLC) revealed quantitative and qualitative differences in lipid composition of tumour cells when compared with goitre cells from normal thyroid gland and subcutane fat. Qualitative differences in triglyceride composition (by HPLC) between tumour cells and subcutaneous fat indicated that the fat accumulation in the follicle cells was not a result of simple storage, but an expression of altered intracellular lipid metabolism.

Adenoma↗

PubMed1990

Multiple myeloma arising from solitary plasmacytoma of bone.

Double (kappa + lambda), Bence Jones (BJ) proteinuria was detected in a male patient of 73 years. The disease started as a solitary plasmacytoma in bone and transformed into multiple myeloma. At the beginning, isolated BJ lambda proteinuria was observed which was soon accompanied by transient excretion of BJ kappa protein.

Aged↗

PubMed1990

Investigation of drug-containing multiple phase emulsions.

We studied the efficiency of the formation of w/o/w emulsions as a function of composition and mixing time. We found that the concentration of emulsifier 1, the concentration and HLB of emulsifier 2, the viscosity of the oil phase and the external water phase as well as the mixing time in second step of preparing the emulsion characteristically influence the "efficiency" of emulsification and the stability of the emulsions.

Chemistry, Pharmaceutical↗

PubMed1989

[Follow up of thyroglobulin levels in patients with surgically treated, highly differentiated thyroid cancer].

The highly differentiated thyroid tumours account for 0.80 percent of all human malignancies. The papillary and follicular tumour tissues of this tumour type are relatively benign, hormone dependent and beside their treatment specificity they secrete the tumour specific thyreoglobulin. Thus it becomes possible to follow the development of metastases, the effectiveness of therapy applied as well as the history of the disease. The authors studied the change of thyreoglobulin level in 153 patients with highly differentiated thyroid cancer. In 29 of 32 metastatic patients pathologically elevated (70 to 100 ng/ml) thyreoglobulin level was observed. This proves the 91 percent specificity of the method in verified metastatic tumours. Compared to the total body scintigraphy 3 false negative cases were found. The authors establish that, irrespective of the site of metastasis, the thyreoglobulin level is higher in the follicular than in the papillary subtype. It is concluded that the measurement of the serum thyreoglobulin level is a suitable marker of the highly differentiated thyroid cancer since it represents the local recurrence of distant metastases with a significant increase while the therapy-resultant tumour diminution with a marked decrease, respectively.

Adenocarcinoma↗

PubMed1989

Comparison of the polymorphic modifications of famotidine.

The polymorphic modifications of famotidine are described and characterized by their spectroscopic (infrared, X-ray) and some physico-chemical data. In addition to the standard physico-chemical data (melting point, solubility, bulk density) some further properties influencing its use in pharmaceutical technology are also characterized. The methods used to prepare the morphologically homogeneous modifications are also given.

Calorimetry, Differential Scanning↗

PubMed1989

Postoperative thyroglobulin level determination to follow up patients with highly differentiated thyroid cancer.

The highly differentiated thyroid tumours account for 0.80% of all human malignancies. The papillary and follicular tumour tissues of this tumour type are relatively benign, hormone-dependent and beside their treatment specificity they secrete the tumour-specific thyroglobulin. This it becomes possible to follow the development of metastases, the effectiveness of therapy applied as well as the history of the disease. The authors studied the change of thyroglobulin level in 153 patients with highly differentiated thyroid cancer. In 29 of 32 metastatic patients a pathologically elevated (70-100 ng/ml) thyroglobulin level was observed. This proves the 91% specificity of the method in verified metastatic tumours. Compared to the total body scintigraphy 3 false-negative and 6 false-positive cases were found. The authors establish that, irrespective of the site of metastasis, the thyroglobulin level is higher in the follicular than in the papillary subtype. It is concluded that the measurement of the serum thyroglobulin level is a suitable marker of the highly differentiated thyroid cancer since it indicates local recurrence or distant metastases by a significant increase while therapy-resultant tumour diminution is accompanied by a marked decrease.

Adult↗