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1.
Azido-3'-deoxy-thymidine (AZT) is a drug extensively used in the treatment of AIDS. AZT was incubated in vitro either with the pituitary-hypothalamus complex (PHc) or the intact pituitary (PI) of male rats. The PHc is comprised of the hypothalamus and the attached pituitary gland. After a preincubation period, the PHc or PI was incubated for 1 or 2 h with Krebs-Ringer bicarbonate buffer or either of two different concentrations of AZT (1 and 10 microM). In the control incubations, the PHc released less prolactin (PRL) and more follicle-stimulating hormone (FSH) and luteinizing hormone (LH) than the PI, indicating that hypothalamic control of the pituitary was exerted in vitro, presumably by diffusion of releasing and inhibiting hormones from the neurohypophysis to the anterior lobe of the hypophysis. Both concentrations of AZT evoked a significant increase in release of PRL and a decreased release of LH and FSH from the PHc. In the case of LH, the higher concentration of AZT partially suppressed LH release within 1 h. The other effects were not dose-related and were observed after incubating the tissue with AZT for 2 h. However, incubation of the PI with AZT failed to alter anterior pituitary hormone release, illustrating that the site of action of AZT is in the hypothalamus. We hypothesize that AZT blocks DNA synthesis resulting in suppression of synthesis and consequent release of hypothalamic hormones that control release of pituitary hormones in vitro. The results raise the possibility that AZT may alter hypothalamic-pituitary function in vivo.  相似文献   

2.
We studied 1771 patients treated for a thyroid cancer in two institutions. None of these patients had been treated with external radiotherapy and 1497 had received (131)I. The average (131)I cumulative activity administered was 7.2 GBq, and the estimated average dose was 0.34 Sv to the bone marrow and 0.80 Sv to the whole body. After a mean follow-up of 10 years, no case of leukaemia was observed, compared with 2.5 expected according to the coefficients derived from Japanese atomic bomb survivors (P = 0.1). A total of 80 patients developed a solid second malignant neoplasm (SMN), among whom 13 developed a colorectal cancer. The risk of colorectal cancer was found to be related to the total activity of (131)I administered 5 years or more before its diagnosis (excess relative risk = 0.5 per GBq, P = 0.02). These findings were probably caused by the accumulation of (131)I in the colon lumen. Hence, in the absence of laxative treatment, the dose to the colon as a result of (131)I administered for the treatment of thyroid cancer could be higher than expected from calculation of the International Commission on Radiological Protection (ICRP). When digestive tract cancers were excluded, the overall excess relative risk of second cancer per estimated effective sievert received to the whole body was -0.2 (P = 0.6).  相似文献   

3.
A 37-year-old woman was seen for recurrent papillary carcinoma of the thyroid after thyroidectomy. After repeated surgery and I-131 therapy, follow-up I-131 scanning and thyroglobulin levels were negative. Subsequent I-131 surveillance, however, demonstrated bilateral breast uptake. A biopsy taken of this area in the right breast proved that the increased uptake was secondary to benign disease.  相似文献   

4.
Correlation of serum thyroglobulin (Tg) levels with recurrent cancer was performed in 200 patients who had undergone a subtotal thyroidectomy for well-differentiated thyroid carcinoma. Patients were divided into three groups: (1) those not treated postoperatively with radioactive iodine, (2) those treated with low dose (30 mCi) radioactive iodine, and (3) those treated with high dose (50-250 mCi) radioactive iodine. Tg levels proved to be reliable in detecting recurrent thyroid cancer regardless of the dose of radioactive iodine given postoperatively. These results reinforce the recommendation of using the Tg assay as the primary method of following these patients postoperatively, even when there was less than a total thyroidectomy and ablation with radioactive iodine.  相似文献   

5.
This study evaluates the pharmacokinetics, dosimetry, toxicity and therapeutic potential of radiolabeled NP-4 and MN-14 anti-CEA antibodies in medullary thyroid cancer (MTC). METHODS: Eighteen patients with advanced MTC entered exploratory clinical studies with therapeutic doses of 131I-labeled NP-4 and MN-14 murine monoclonal antibodies (MAbs) reactive with carcinoembryonic antigen (CEA). Doses administered ranged from 46 mCi for 131I-MN-14 lgG to 195 mCi for 131I-MN-14 F(ab)2 in patients negative for human anti-mouse antibodies (HAMA). RESULTS: The radioconjugate blood half-life (T1/2) for the whole lgG was 42.5+/-5.0 hr compared to 18.8+/- 4.1 hr for the bivalent fragments. Tumor doses of 17.5+/-11.0 and 11.4+/-6.3 cGy/mCi were estimated for 131I-MN-14 lgG and F(ab)2, respectively. Tumor/red marrow dose ratios exceeded 3:1 for most lesions. Red marrow doses of up to 350 cGy generally could be delivered with < grade 4 toxicity. Seven of 14 evaluable patients showed evidence of anti-tumor effects lasting up to 26 months, based on physical exam, tumor markers or computed tomography. CONCLUSION: This study demonstrates that anti-CEA MAbs may be suitable for radioimmunotherapy of metastatic or recurrent MTC.  相似文献   

6.
Renal disease in patients infected with human immunodeficiency virus (HIV) often presents with significant proteinuria and progressive renal failure; focal glomerulosclerosis is the most common renal pathology identified. To our knowledge, we report the first case of nephrotic-range proteinuria and preserved renal function in an HIV-infected patient in association with disseminated histoplasmosis. The initial level of proteinuria was 12.5 g/24 h. The patient developed a concomitant lesion on his neck, which was biopsied and identified as Histoplasma capsulatum by fungal stains and culture. The serum CF titer of antibody against yeast antigens of H. capsulatum was 1:8. The level of serum albumin decreased to 2.0 g/dL, and the level of serum cholesterol increased to 284 mg/dL. Immunohistochemical staining of renal biopsy tissue demonstrated immune complexes within the mesangium; H. capsulatum antigen was also demonstrated in the mesangium. Therapy with oral itraconazole resulted in marked clinical improvement. The findings in this case emphasize the need to rule out treatable causes of the nephrotic syndrome in AIDS, especially in cases of immune-complex glomerulonephritis.  相似文献   

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Based on sequence analyses of 17 complete centromeric DNA monomers from ten different deer species, a model is proposed for the genesis, evolution, and genomic organization of cervid satellite I DNA. All cervid satellite I DNA arose from the initial amplification of a 31-bp DNA sequence. These 31-bp subrepeats were organized in a hierarchical fashion as 0.8-kb monomers in plesiometacarpalia deer and 1-kb monomers in telemetacarpalia deer. The higher-order repeat nature of cervid centromeric satellite DNA monomers accounts for their high intragenomic and intraspecific sequence conservation. Such high intraspecific sequence conservation validates the use of a single cervid satellite I DNA monomer from each deer species for interspecific sequence comparisons to elucidate phylogenetic relationships. Also, a specific 0.18-kb tandem duplication was observed in all 1-kb monomers, implying that 1-kb cervid satellite I DNA monomers arose from an unequal crossover event between two similar 0.8-kb ancestral DNA sequences.  相似文献   

10.
The clinical behavior and outcome was evaluated in 21 nonoccult differentiated thyroid carcinomas occurring in Graves' patients during the period 1982-94 and compared with that of matched tumors occurring in euthyroid controls (n = 70). At surgery, patients with Graves' disease showed distant metastases more frequently than euthyroid patients (3/21 = 14.3% vs. 1/70 = 1.4%, P = 0.0556). Graves' patients also showed a significantly higher cumulative risk of recurrent/progressive distant metastases or total adverse events (odd ratios = 3.14 and 2.07, respectively) as compared with euthyroid patients. At the last follow-up visit, persistence of distant metastases was also more frequent in the Graves' group (P = 0.007), although the cumulative individual dose of radioiodine administered was higher than in the control group (median dose = 805 mCi vs. 350 mCi). Two patients died in the Graves' group vs. none in the control group. Circulating thyroid stimulating antibodies were present in all patients but one and persisted as long as signs of disease were evident. These findings indicate that differentiated thyroid carcinomas in patients with Graves' disease are more aggressive than those occurring in matched euthyroid controls and should, therefore, be managed accordingly.  相似文献   

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A consensus meeting held by the Chilean Endocrinological Society reached to 22 consensus proposals on the use of iodine-131 in hyperthyroidism and thyroid cancer, that are reported in this paper. Some of these propositions are: 1) Hyperthyroidism: A previous 131I uptake test must be performed. A calculated or an ablative dose should be administered. Hypothyroidism must be considered an objective rather than a complication. In patients with cardiovascular risk, normal thyroid function must be attained with prophythioturacil. In cases of treatment failure, the dose should not be repeated before six months. It must be used with used with caution in children and teenagers. 2) Thyroid cancer: A iodine free diet is recommended prior to the therapeutic dose. A 100 mCi complementary ablative dose should be given after surgery, with a posterior exploration. This examination must not be done routinely, and if required, a 5 mCi dose should be used. For the treatment of metastases, a dose of 150 to 200 mCi is recommended. There is no radiation risk in hyperthyroidism or thyroid cancer. The only absolute contraindication is pregnancy. Recommendations for radiological protection are formulated. Hospitalization is suggested to protect other people from radiation exposure.  相似文献   

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A 40-year-old female patient with Werner's syndrome (WS) suffering from thyroid cancer and myelodysplastic syndrome (MDS) is reported. She had been diagnosed as having WS complicated with thyroid cancer seven years previously. Total thyroidectomy and radioactive iodine (131I, 100 mCi/year) therapy for seven years had slowed the progression of thyroid cancer. She suffered a sudden onset of MDS at the age of 40 years. After six months she died from overt leukemia. We found an additional chromosome aberration of chromosome 10 in the progression of leukemia from MDS.  相似文献   

15.
Juvenile myelomonocytic leukemia (JMML) carries a poor prognosis. The endogenous production of cytokines by the JMML cells contributes to their growth and therapeutic resistance. Interleukin (IL)-4, IL-10, and IL-13 inhibit cytokine production in monocytes. We have now studied whether these cytokines can inhibit JMML cell cytokine production, thereby potentially reducing the malignant cell load in this disorder. We found that IL-10, but not IL-4 or IL-13, dose dependently inhibited JMML cell production of the hemopoietic growth factors granulocyte-macrophage colony-stimulating factor, tumor necrosis factor alpha, and IL-1beta. Similarly, IL-10, but not IL-4 or IL-13, suppressed JMML colony formation and cell viability. This was not due to the absence of receptors because we could detect mRNAs for the IL-4 and the IL-13 receptor alpha subunits and the IL-2 common gamma subunit in JMML cells. Furthermore, the receptors were active since both IL-4 and IL-13 up-regulated surface expression of MHC class II and down-regulated CD14 antigens on JMML cells and monocytes. Unlike activated monocytes, the JMML cells did not produce IL-10. It is suggested that the loss of cytokine inhibitory effects of IL-4 and IL-13 could play a role in the pathogenesis of this disorder. On the other hand, the inhibition of cytokine production, growth, and viability of JMML cells by IL-10 suggests that this cytokine may have a therapeutic potential in JMML.  相似文献   

16.
Quality of life (QOL) is an important consideration as patients survive longer with cancer and is an area of increasing interest in patients with thyroid cancer who undergo long-term cancer surveillance. However, there are few disease-specific QOL tools available to evaluate QOL in patients with thyroid cancer. The purposes of this longitudinal, repeated-measures study were to: (1) test a new instrument, the QOL-Thyroid Scale, during thyroid hormone withdrawal; and (2) to evaluate the impact of thyroid hormone withdrawal on patients' perceived changes in quality of life. The sample included 34 subjects (mean age 40 years) undergoing thyroid hormone withdrawal in preparation for scanning procedures. Subjects completed three instruments (demographic data tool, the QOL-Thyroid, and the FACT-G) at four specific time points in relationship to scanning. The results demonstrated that the QOL-Thyroid tool is a reliable and valid measure of QOL. Cronbach's alpha coefficient of r = .78 between QOL-Thyroid and FACT-G indicated good concurrent validity. Second, the impact of thyroid hormone withdrawal on QOL showed significant changes in physical, psychological, and social well-being across the four testing points. The greatest changes occurred between peak hormone withdrawal and thyroxine (T4) therapy. While it is generally known that patients suffer troublesome physical symptoms relating to thyroid hormone withdrawal, the negative psychological, family, and work sequelae are less apparent. In conclusion, the QOL-Thyroid is a reliable and valid measure for use in evaluating patients undergoing scanning procedures and may be used to identify and target teaching and support for high-risk areas in patients lives that are negatively affected by hormone withdrawal.  相似文献   

17.
Mammography is of real assistance to the surgeon in evaluating breast problems not associated with a breast mass. Use of mammography in the detection of early breast cancer in breast demonstration projects has brought forth the time honored value judgement of benefit vs risk. This report introduces an additional aspect in the consideration of benefit vs risk, the interval cancer. From the demonstration project at KUMC, 326 biopsies were performed and 65 proved to be cancer. However, 24 additional women developed cancer before their next recommended screening date. This reduces the accuracy of mammography and physical examination by trained nurses in screening for breast cancer to 73%.  相似文献   

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The feasibility of mass population screening for breast cancer by clinical examination and x-ray mammography was studied. The results indicate that such a programme could be conducted effectively by non-medical staff and be safe from the dangers of irradiation. The response rate of women invited for screening suggests that such a service is acceptable to the general public. The additional work load produced by screening would not overburden the existing surgical services.  相似文献   

20.
As part of a continuing series on how the work of pathology laboratories contributes to patient care, this article looks at the Papanicolaou (Pap) or cervical smear test, which involves the microscopical examination of cells recovered by scraping the surface of the cervix. The incidence, causes and aetiology are described and the organisation of cervical screening is shown. Finally, the range of findings from a positive smear test is explained.  相似文献   

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