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Biomedical subjects

H Asakawa

Publications and source records attributed to H Asakawa.

At least 37 records · Page 2Linked to original sources

Identification of pathologic parathyroid glands in patients with primary hyperparathyroidism.

Localization of the parathyroid glands is not necessarily easy before surgery and can also be troublesome during surgery. This study focuses on the identification of pathologic parathyroid glands. The records of 32 patients who underwent parathyroidectomy at our institution in the past 14 years for primary hyperparathyroidism were reviewed. Twenty-three patients had a single lesion while 9 had multiple-gland involvement. Localization studies identified 17 of 23 patients with a single lesion. All patients with multiple lesions were diagnosed with an enlargement of the parathyroids, but not all glands were identified in each patient preoperatively. At surgery, 8 of 32 patients were explored unilaterally. Solitary enlarged glands were resected, and a subtotal parathyroidectomy was performed for multiple-gland involvement. The intraoperative serum intact parathyroid hormone (PTH) level dropped after resection of the largest gland. The serum PTH level correlated with the gland size (r = 0.861, intact PTH assay). Eight of 9 patients with multiple-gland involvement had an elevated serum PTH (>2000 pg/ml in midportion and >200 pg/ml in intact PTH assays, respectively). No patient developed persistent or recurrent hyperparathyroidism. The serum PTH level was normalized by a resection of relatively enlarged glands in our cases. It is usual to explore all glands during surgery, and in cases with a high serum PTH level, multiple-gland involvement should also be considered.

Adult↗

Two M-components in a single cell lineage in a patient with a dual isotype secretory B-cell tumour.

We describe a case of Waldenström's macroglobulinaemia with two M-components (IgM and IgG) with the same lambda light chain. Southern blot analysis of bone marrow cells showed rearrangements of immunoglobulin heavy and lambda light chain genes. Sequencing of the complementarity determining region 3 of the two lambda and mu transcripts showed 100% homology. Immunofluorescence study showed that most cells stained for both IgG and IgM. These findings indicated that a single population of cells was expressing two isotypic variants of IgG and IgM, as the genes responsible for production of both components had the same origin.

Base Sequence↗

Prognostic factors in patients with recurrent differentiated thyroid carcinoma.

BACKGROUND: Approximately 20% of patients with thyroid carcinoma have relapse. To evaluate the factors affecting their disease-free survival and prognosis, we studied 68 patients with recurrent differentiated thyroid carcinoma, ranging in age from 5 to 73 years (mean: 47.6 years). Three-fourths of patients were followed for >10 years. Thirty-nine patients were treated with total or subtotal thyroidectomy at first operation; the remainder underwent lesser operations. Fifty-six patients had local recurrence, mostly lymph node infiltration. Twenty-six patients died. METHODS: Survival curves were constructed using the Kaplan-Meier method. Factors affecting relapse and survival were tested by univariate or multivariate analysis. RESULTS: Univariate analysis identified age at diagnosis, local tumor extension, and surgical method as significant factors for disease-free survival. These three factors and histology were significant prognostic factors. Multivariate analysis showed age, histology, and disease-free interval as significant and independent variables. CONCLUSIONS: In high-risk patients, complete resection of thyroid tissue and cervical lymph nodes is critical.

Adolescent↗

A patient with Graves' disease, myasthenia gravis, and polymyositis.

Graves' disease (GD), myasthenia gravis (MG), and polymyositis (PM) are organ-specific autoimmune diseases. The association between GD and MG is well known, and an association between MG and PM has been reported. However, only one patient with all three diseases has been reported. We describe a patient with GD and PM developing 6 and 29 years, respectively after the onset of MG. This case suggests that the expression of autoimmunity occurred over a prolonged period of time and these organ-specific autoimmune diseases may be induced by a similar mechanism.

Adolescent↗

Laparoscopic prediction of hepatocellular carcinoma in cirrhosis patients.

Previously, laparoscopic studies have not been successful in predicting the occurrence of small hepatocellular carcinoma because cirrhotic patients had not been separated into groups of those who developed small hepatocellular carcinoma under 3 cm in diameter, and those who did not. Retrospective examination with better separation of the two groups gave improved results. Of the 26 laparoscopic findings, only the presence of large complex regenerative nodules was closely associated with the occurrence of subclinical small hepatocellular carcinoma. The study of other cirrhotic patients with and without large complex regenerative nodules gave a cumulative hepatocellular carcinoma occurrence rate of 73% for patients who had these nodules by the third year after laparoscopy. In contrast, the rate for patients without such nodules was 6%, showing a significant difference (P < 0.05) between the two groups. We concluded that the laparoscopic finding of large complex regenerative nodules of liver cirrhosis can be used to predict the occurrence, or a complication, of subclinical small hepatocellular carcinoma.

Carcinoma, Hepatocellular↗

Clinical and genetic analysis of an inherited case of thyroid adenoma/cancer.

We studied a family in which thyroid neoplasms appeared to occur through genetic inheritance. Six blood relations, including the two probands, had thyroid carcinoma, and six others had benign thyroid tumors. When both parents had a thyroid neoplasm, their children frequently had thyroid neoplasms; this was confirmed through two generations of this family. To clarify the mechanism of inheritance, we performed chromosomal analysis, Southern blot analysis of three variable number of tandem repeats markers and HLA typing on two probands, and examined their RET proto-oncogenes, and p53 and RB tumor suppressor genes. We could not find any positive data on genetic analysis, although our data were limited. In conclusion, we studied a family in which thyroid neoplasms have occurred partly through genetic inheritance, although environmental factors may have influenced the occurrence of thyroid diseases. A search for a predisposing gene, using the microsatellite technique, is required to clarify the gentic factors involved.

Adenoma↗

Fatal differentiated thyroid cancer.

Thirty-five patients who died of differentiated thyroid cancer were analyzed for factors affecting survival. The neck was the most common initial site of recurrence (62.0%). The lung was the most common metastatic site (56.7%). Major sites associated with death were locoregional recurrence (neck and mediastinum: 48.6%) and bone metastases (22.9%). By univariate analysis, local tumor extension, type of initial surgery, and residual tumor and/or existence of distant metastases at the initial operation were significant factors affecting survival. Stepwise multivariate analysis revealed that invasion of the esophagus and/or carotid artery shortened survival and that multiple surgeries extended survival. Our results suggest that to improve survival in patients with differentiated thyroid cancer, better locoregional control, including multiple surgical resection, is necessary.

Adult↗

High glucose and hyperosmolarity increase heparin-binding epidermal growth factor-like growth factor (HB-EGF) production in cultured human aortic endothelial cells.

Heparin-binding epidermal growth factor-like growth factor (HB-EGF) has been shown to be a potent smooth muscle cell (SMC) mitogen and chemoattractant, and might be a candidate factor for the progression of atherosclerosis. We have investigated the effects of high glucose and hyperosmolarity on HB-EGF production in cultured human aortic endothelial cells. Following the culture of the cells for 2 days with high concentrations of glucose or in the hyperosmolar conditions, we measured the content of HB-EGF and the rate of production in the cells using a semi-quantitative immunofluorescent technique and a metabolic radiolabelling method. With high glucose (16.6 mmol) and hyperosmolar conditions (glucose 5.5 mmol + mannitol 11.1 mmol or glucose 5.5 mmol + raffinose 11.1 mmol), the content of HB-EGF was significantly increased and the metabolic rate was also significantly increased (more than a twofold increase, compared to that of 5.5 mmol glucose). In conclusion, conditions of high glucose or hyperosmolarity increase HB-EGF production in human aortic endothelial cells. These results suggest that diabetic macroangiopathy might be attributed at least in part to HB-EGF-related vascular changes which may be induced by glucose.

Aorta↗

Effects of interleukin-1 beta on scanning electron microscopic appearance and thyroid peroxidase content of human thyrocytes in monolayer culture.

Interleukin (IL-1), an inflammatory cytokine that is detected in the thyroid tissues of patients with autoimmune thyroiditis, is believed to be involved in the disease process. To clarify the role of IL-1 in the development of autoimmune thyroiditis, we investigated the effects of interleukin-1 beta (IL-1 beta) on the morphology of human thyrocytes in monolayer culture as well as the effect on thyroid peroxidase (TPO) content of these cells. Human normal thyrocytes were cultured with IL-1 beta for 4 days in the presence and absence of TSH. In morphologic studies, cultured cells were fixed for examination by scanning electron microscopy and for immunofluorescent staining of acting filaments. IL-1 produced striking morphologic changes in the cultured thyrocytes, including the cytoplasmic retraction and dissociation and/or depolymerization of actin filaments. These changes were unrelated to TSH stimulation. For detection of TPO, cultured cells were stained by an immunofluorescent technique and analyzed by fluorescence photometry. IL-1 reduced the TPO content and inhibited the TSH-induced increase in TPO in a concentration-dependent manner. These morphological changes and the reduction in TPO content of cultured thyrocytes suggest that IL-1 modulates the pathophysiology of autoimmune thyroiditis.

Adult↗

Successful erythropoietin treatment for severe anemia in nephrotic syndrome without renal dysfunction.

A 62-year-old woman presented with nephrotic syndrome and severe anemia although the renal function was not impaired. Renal biopsy revealed the histology of membranoproliferative glomerulonephritis, and the proteinuria was resistant to steroid therapy. Iron deficiency, bleeding and other causes of anemia were ruled out, however, her serum erythropoietin level was inappropriately low. The anemia was rapidly corrected by administration of recombinant human erythropoietin. It is suggested that inappropriately low erythropoietin level, in part at least, accounts for the anemia in nephrotic syndrome. It is proposed that erythropoietin therapy should be taken into consideration for severe anemia in nephrotic syndrome even when the renal function is not impaired.

Anemia↗

Establishment of anaplastic thyroid carcinoma cell lines useful for analysis of chemosensitivity and carcinogenesis.

Anaplastic thyroid carcinoma (ATC) is usually associated with a poor prognosis, with most patients dying within a few months. The mechanism of its carcinogenesis is unclear, and its rapid growth and spread often prevent effective surgical therapy. Thus, chemotherapy is necessary. However, ATC is often resistant to anticancer drugs. Therefore, prediction of chemosensitivity is important in selecting appropriate treatment. In this study, after the establishment of three cell lines (K119, KOA2, and IAA) from patients with ATC, we analyzed them for abnormalities in certain oncogenes (myc, ras, ret, and c-erbB2) and the p53 tumor suppressor gene. Only one of three cell lines (KOA2) had a N-ras mutation [codon 61 CAA(Gln)-->CGA(Arg)] and a p53 gene mutation [exon 6 codon 192 Caa(Gln)-->TAG(stop)]. We also investigated their in vitro drug sensitivity and compared it with clinical chemosensitivity, retrospectively. In vitro drug sensitivity was determined using an adhesive tumor cell culture system. Only the K119 cells were sensitive to adriamycin and cisplatin in vitro. The other two were resistant to them in vitro. These results paralleled the clinical responses. We also evaluated the in vitro drug sensitivity of a poorly differentiated thyroid carcinoma cell line (SMP) and papillary thyroid carcinoma cell lines (NPA). None of the five cell lines expressed the multidrug resistance gene (mdr-1). In conclusion, we established ATC cell lines that are suitable models for characterizing the nature of multidrug resistance and carcinogenesis.

Aged↗

Spinal extradural meningeal cyst. Case report.

The case of a 30-year-old man with a spinal extradural meningeal cyst in the thoracolumbar region is reported. Operative findings revealed a dural defect that allowed communication between the extradural cyst cavity and the subarachnoid space. Application of the Valsalva maneuver made the cerebrospinal fluid flow into the cyst cavity; however, reverse flow did not occur. These findings indicate that a valvelike mechanism developed in the enlarging cyst. Surgical resection of the cyst wall and closure of the dural defect provided a favorable result.

Adult↗

[Late coronary artery aneurysm formation following directional coronary atherectomy].

The most important factor to reduce late restenosis following directional coronary atherectomy is the technical provision of the largest luminal diameter as possible. However, the safety of deep arterial resection and the resulting arterial perforation or late aneurysm formation is questionable. This study examined the frequency of coronary artery aneurysm formation in patients treated by directional coronary atherectomy. Ninety-eight patients with 123 lesions were analyzed by quantitative angiographic and histologic data. Coronary aneurysms (ratio of dilated vessel segment to the adjacent reference segment > 1.2:1) occurred in seven patients (seven lesions: 5.7%). Specimens were categorized by the deepest layer retrieved. Forty lesions (32.5%) were treated by resection of the intima alone, 65 (52.8%) by resection of the medial tissues and 18 (14.6%) received resections of the adventitial tissues including fatty tissues in three lesions. Late coronary aneurysms occurred often in lesions with resection of adventitial tissue (38.9%) and occurred in all three lesions with resections of fatty tissues. Six coronary aneurysms occurred in the left anterior descending artery (six in segs. 6, 7), and one aneurysm in the left circumflex artery. Among the target lesions in which coronary artery aneurysms were formed, six lesions were primary lesions and one lesion was a restenotic lesion after percutaneous transluminal coronary angioplasty. Statistically, patients with coronary artery aneurysms frequently have associated hypertension (p = 0.02) but rarely diabetes mellitus (p = 0.05). Lesions with late aneurysms had significantly high specimen weight (p = 0.01) and a trend to lower postprocedure % diameter (p = 0.20). There was no significant preprocedural angiographic predictor of aneurysms such as minimal lumen diameter or reference vessel diameter.

Adult↗

[A basic study on gastric emptying test using barium grains and effect of drugs on gastric emptying in rats].

We reported an experimental study on a new non-invasive method for evaluation of gastric emptying by abdominal X-ray after administration of radiopaque barium grains. Adult male Wistar rats weighing around 200 g were used. After they were fasted for 24 hours, 1 ml of gruel mixed with 10 barium grains (1 mm diameter) was introduced into the rat stomach with a catheter. The rats were sacrificed at 30, 60, 90, 120 and 150 minutes after the introduction of the gruel. X-rays were taken at each time point and grains in the stomach were counted in the X-ray photographs. All barium grains were emptied from the stomach in 150 minutes. After incision of the abdomen, the residual gastric contents were weighed. A positive correlation was found between the grains in the stomach and the weight of the contents. We studied the effects of cisapride, scopolamine buthylbromide and enprostil on the gastric emptying time by this method. Cisapride accelerated gastric emptying, whereas scopolamine buthylbromide delayed it. A prostaglandin E2 analog, enprostil delayed the gastric emptying. This method was found to be a simple procedure which is outstanding for quantitative determination and useful in evaluating gastric emptying functions.

Animals↗

Leukoencephalopathy in childhood hematopoietic neoplasm caused by moderate-dose methotrexate and prophylactic cranial radiotherapy--an MR analysis.

PURPOSE: The main purpose of this study was to determine influential factors related to minor leukoencephalopathy (LEP) caused by moderate-dose methotrexate (MTX) and prophylactic cranial radiotherapy (CRT) in childhood hematopoietic malignancies. We also compared the incidence of LEP following this treatment to that reported in the literature following treatment with high-dose MTX alone. METHODS AND MATERIALS: Thirty-eight pediatric patients of hematopoietic malignancies (37 acute lymphoblastic leukemias, 1 non-Hodgkin lymphoma) who were given CRT (18-24 Gy) as well as prophylactic intrathecal and per os MTX were studied for leukoencephalopathy by magnetic resonance (MR) imaging. All the patients were free from grave neuropsychiatric disturbances. The data were examined to elucidate the influential ones of five factors (patients' age, doses of intrathecal and per os MTX, dose of CRT, interval between treatment, and MR study) to develop LEP using multiple regression analysis. To compare the effect of moderate-dose MTX and prophylactic CRT on LEP to that of high-dose MTX alone, we conducted literature review. RESULTS: Seven out of 38 patients (18%) developed LEP. From multiple regression analysis and partial correlation coefficients, the age and CRT dose seemed influential in the subsequent development of LEP. The incidence of LEP following treatment with moderate-dose MTX and prophylactic CRT appears to be less than that reported in the literature following treatment with intravenous high-dose MTX. However, even moderate-dose MTX in combination with CRT can result in a significant incidence of MR-detectable LEP, particularly in children 6 years of age or younger receiving 24 Gy. CONCLUSION: Leukoencephalopathy was caused by moderate-dose MTX and prophylactic CRT in pediatric patients, probably less frequently than by high-dose MTX treatment alone. The influential factors were patient's age and CRT dose.

Adolescent↗