Biomedical subjects

J Hata

Publications and source records attributed to J Hata.

At least 73 records · Page 4Linked to original sources

PubMed2000

Collaborative work to evaluate toxicity on male reproductive organs by repeated dose studies in rats 1). Effects of 2-weeks daily administration of estradiol benzoate.

As part of a collaborative project to assess whether a 2-weeks administration period is sufficient to detect testicular toxicity of various compounds, male rats were subcutaneously administered 0, 5, 20, 50 or 100 micrograms/kg of estradiol benzoate (E2B), a known testicular toxicant, daily for 2 or 4 weeks. After 4-weeks, suppression of body weight gain, increase in the weight of the adrenal gland, and gross changes such as decrease in size of the prostate and seminal vesicles, and increase in size of the adrenal gland were observed in the 5, 20, 50 and 100 micrograms/kg groups. On histopathological examination, degeneration/necrosis of Pachytene spermatocytes, atrophy of Leydig cells, mature spermatid retention (Lee, et al., 1993) at stages IX, X and XI, and atrophy of ducts of the epididymides were also observed in the 5, 20, 50 and 100 micrograms/kg groups. After 2-weeks, the same changes were also observed with 20, 50 and 100 micrograms/kg, but not 5 micrograms/kg. These results indicate that the toxic effects of E2B are detectable by administration for 2 weeks at an appropriate dose level.

Adrenal Glands↗

PubMed2000

[A case of metanephric adenoma treated with partial nephrectomy].

A 32-year-old female presented with a right renal mass detected by abdominal ultrasound examination at a routine medical check up. Computed tomography scans and magnetic resonance images revealed a solid tumor in the upper pole of the right kidney measuring 1.5 cm in diameter. Partial nephrectomy was performed on suspicion of the renal cell carcinoma. Histologically, the tumor is composed of small, uniform, epithelial cells with scant cytoplasm and hyperchromatic round nuclei that formed a tubular or glomerular-like structure. The histological diagnosis was metanephric adenoma.

Adenoma↗

PubMed2000

Evaluation of flash echo imaging of the canine gastrointestinal tract.

Although it is important to assess gastrointestinal blood flow, no generally useful, noninvasive assessment method has been established. Harmonic flash echo imaging, which is an intermittent second harmonic imaging technique, has recently become available to evaluate blood flow. We investigated the usefulness of harmonic flash echo imaging in the assessment of the gastrointestinal tract, and we used this technique to study the effect of nicotine on small bowel blood flow. Harmonic flash echo imaging was performed at the beginning of intravenous injection of a contrast agent. It was also performed on the small bowel immediately before and 10 min after nicotine administration to evaluate blood flow. Gastric and small bowel walls were clearly enhanced on the primary images. Small bowel enhancement, which is regarded as transmural blood flow, significantly decreased after nicotine administration. Harmonic flash echo imaging appears to be useful in the assessment of the transmural blood flow in the gastrointestinal wall.

Animals↗

PubMed2000

Ultrasonography improves diagnostic accuracy of acute appendicitis and provides cost savings to hospitals in Japan.

A cost analysis based on changes in patient care was used to evaluate the utility of abdominal ultrasonography in both the clinical management of patients clinically suspected of having acute appendicitis and in reducing expenditure of hospital resources. Among the 200 patients suspected of having acute appendicitis, 57 actually had acute appendicitis. Interpretation of appendiceal ultrasonographic results was 98.5% accurate. The ultrasonographic result led to changes in the treatment of 103 patients. Moreover, ultrasonography led to the prevention of unnecessary appendectomy in 25 patients, providing a savings to the hospital of about Yen 8,013,450 ($65,150), and prevented unnecessary hospital admission for 78 patient-days, thus saving the hospital approximately Yen 1,199,250 ($9750). The cost of performing the 200 ultrasonographic examinations was about Yen 1,096,176 ($8912), and thus the overall savings to the hospital was approximately Yen 40,590 ($330) per patient. Ultrasonography performed in patients with suspected acute appendicitis improves patient diagnostic accuracy, thus leading to more appropriate selection of patient treatment and reduced hospital expenditure.

Acute Disease↗

PubMed2000

A case of aortoduodenal fistula occurring after surgery and radiation for pancreatic cancer.

The patient was a 58-year-old woman given curative treatment (pancreatectomy (body and tail) + intraoperative irradiation (25 Gy)) on the basis of a diagnosis of pancreatic carcinoma. Having a favorable postoperative course, she was discharged 24 days after surgery. A week after discharge, she was readmitted for a hemorrhagic gastric ulcer. She was later discharged again on conservative treatment, and followed up at the outpatient clinic, but nine months postoperatively, was readmitted complaining of loss of appetite and abdominal pain. Subsequent tests revealed stricture of the horizontal portion of the duodenum with distension oral to the stricture. Around the celiac artery, the paraaortic lymph nodes were swollen, and a diagnosis of stricture due to recurrent pancreatic carcinoma was made. On the day before bypass surgery was scheduled, the patient vomited blood, so the operation was postponed, conservative treatment such as blood transfusion was administered, and emergency angiography was performed simultaneously. The findings were an aortic pseudoaneurym 1 cm in diameter immediately below the origin of the superior mesenteric artery and between the left and right renal arteries, and a hemorrhage, caused by an aortoduodenal fistula, issuing from the horizontal portion of the duodenum. Hemostasis via a laparotomy was judged difficult, and so an indwelling stent-graft in the aorta was tried to stanch the blood, but without success. Another stent then had to be inserted within the first, thus stopping the flow, but the blood supply to the celiac artery, the superior mesenteric arteries and the renal arteries was impaired, and the patient died about six hours later. Postmortem examination revealed aortoduodenal fistula without recurrence of the carcinoma. The duodenal wall around the fistulous tract showed delayed radiation changes with deep ulceration. The intraoperative radiation may have played an important part in the formation of the fistula.

Aortic Diseases↗

PubMed2000

[Choriocarcinoma of the renal pelvis: a case report].

A 68-year-old male presented to our hospital complaining of gross hematuria. Intravenous pyelography subsequently demonstrated a left non-visualized kidney, and he was admitted for further evaluation. Cystoscopy revealed a bladder tumor around the left ureteral orifice and retrograde pyelography showed a filling defect in the left renal pelvis. The urinary cytology from the left renal pelvis indicated class IV, and the microscopic findings of a bladder biopsy demonstrated grade 1 transitional cell carcinoma. We performed transurethral resection of bladder tumor (TUR-BT) followed by left nephroureterectomy with bladder cuff. The pathological diagnosis was high grade transitional cell carcinoma with choriocarcinomatous component. After the operation, the serum human chorionic gonadotropin-beta (hCG-beta) level was slightly elevated, and the combination chemotherapy with methotrexate, vinblastine and cisplatin (MVC) was administered. Although the serum hCG-beta level fell to 0.1 ng/ml, after two courses of MVC chemotherapy, bilateral pulmonary metastases appeared in the chest X-ray with increasing hCG-beta levels. Salvage chemotherapy with cisplatin, etoposide and bleomycin (PEB) was performed. After two courses of PEB chemotherapy, the serum hCG-beta level fell to within the normal range and all pulmonary metastases disappeared.

Aged↗

PubMed2000

[Wilms' tumors and malformation complexes].

Wilms' tumor is an embryonal tumor which is derived from metanephric metanephric blastema. The occurrence of both sporadic and hereditary forms, along with various congenital abnormalities of Wilms' tumor suggest that the tumors develop when a predisposing germ line mutation is accompanied by a second mutation. The existence of both gross chromosomal abnormalities has led to the genetic characterization of a number of loci involved in the development of Wilms' tumor. A tumor suppressor gene for Wilms' tumor, WT1, has been isolated from the 11p13 region. The product of this gene is a transcription factor with four zinc fingers. Because of expression of WT1 is limited to the developing glomeruli of the kidneys and the genital ridge, it is thought to have a functional role in renal and gonadal organogesis. Thus dysfunction of WT1 causes loss of normal regulation of proliferation and leads to tumor formation and occurrence of Wilms' tumor anomaly complexes. The role of the imprinting genes, H19 and IGF2 in oncogenesis of Wilms' tumors are also discussed.

Chromosome Aberrations↗

PubMed2000

A 35-year-old man with cerebral hemorrhage and pheochromocytoma: the second brain-dead organ donor in Japan.

A 35-year-old man was brought into the emergency room of Keio University Hospital by ambulance because of a sudden onset of coma. His Glasgow Coma Scale was 3 and his blood pressure 150/100 mmHg. CT scanning revealed a subcortical hemorrhage 8 cm in diameter. His respiration deteriorated rapidly, and an emergency craniotomy was performed for hematoma removal and cerebral decompression. Postoperatively the patient remained in a deep coma (GCS = 3) requiring respiratory support. The family presented an organ donor card previously signed by the patient, and brain death was confirmed in accordance with Japan's transplant law. As a result of two tests conducted six hours apart brain death was confirmed on the 5th postoperative day. With the family's consent, the donor's heart, kidneys and skin were removed for organ transplantation to be performed in other institutions. An autopsy was performed after the removal of the organs and skin. An extensive subgaleal hemorrhage was found in the left cerebral hemisphere, and microscopic examination revealed extensive necrosis with karyolysis of neuronal cells, but no viable neuronal cells were found in the cerebrum. The brain stem was marked by edema, hemorrhage, infarction necrosis and neuronal cell loss. The cerebellum was swollen and congested and showed autolysis of the granular layer. These findings suggested brain death syndrome with respirator brain. Other autopsy findings included a huge pheochromocytoma in the right adrenal gland, bilateral bronchopneumonia, liver congestion and fatty metamorphosis with four cavernous hemangiomas, and mild chronic lymphocytic thyroiditis. This patient was the second brain-dead organ donor and the first brain-dead patient to undergo postmortem examination in Japan.

Adrenal Gland Neoplasms↗

PubMed2000

A case of poorly differentiated hilar lung adenocarcinoma of an unidentified histological type.

The patient was a 74-year-old man, a physician, whose chief complaint was an unproductive cough. The shadow of a mass was seen at the hilum of the left lung, and the mediastinal lymph nodes on both sides were swollen. No histological diagnosis was obtained even after bronchoscopy, including transbronchial needle aspiration biopsy, but large-cell carcinoma of the lung was diagnosed on the basis of ultrasound-guided biopsy of a shadow in the liver suspected of being a metastatic tumor (T2N3M1, Stage IV). Two courses of chemotherapy (CBCDA + VDS) failed to gain any improvement, and the pain resulting from recurrent bone metastases was managed mainly by the administration of the best supportive care. The patient was readmitted to the hospital after development of numbness in the right upper extremity followed by complication of pneumonia and heart failure, and he passed away. Autopsy revealed a primary hilar lung tumor with a histological diagnosis of poorly differentiated adenocarcinoma.

Adenocarcinoma↗

PubMed1999

The EAT/mcl-1 gene, an inhibitor of apoptosis, is up-regulated in the early stage of acute myocardial infarction.

EAT/mcl-1 (EAT), a bcl-2-related immediate early gene, is up-regulated at an early stage of differentiation of human embryonal carcinoma cells. Recent studies have revealed that EAT inhibits apoptosis both in vitro and in vivo. In the present study, we demonstrated that the EAT gene was up-regulated in the early stage of rat myocardial infarction. This pattern of up-regulation was apparently different from that of another immediate early gene, c-fos. EAT, an anti-apoptotic molecule, was strongly up-regulated in the non-ischemic region. In contrast, the expression of c-fos was induced in both ischemic and non-ischemic regions, and was higher in the ischemic region. Apoptosis of cardiomyocytes is currently thought to significantly contribute to acute myocardial infarction. We detected cardiomyocyte apoptosis by gel electrophoresis of genomic DNA and in situ nick end labeling in the ischemic region, but not in the non-ischemic region. As an inhibitor of apoptosis, EAT may play a role in the protection of cardiomyocytes in the early stage of acute myocardial infarction.

Animals↗

PubMed1999

High frequency of inactivation of the imprinted H19 gene in "sporadic" hepatoblastoma.

Embryonal tumors such as Wilms' tumor (WT), embryonal rhabdomyosarcoma (eRMS) and hepatoblastoma have been thought to have a common pathogenetic mechanism. H19 was found to be inactivated in WT and eRMS either by loss of heterozygosity or by hypermethylation of the maternal allele. We show here that the expression of the H19 gene is inactivated by maternal allelic loss or hypermethylation in 7 out of 8 "sporadic" hepatoblastomas. Furthermore, we analyzed expression of the IGF2 gene. Loss of imprinting of the IGF2 gene was detected and linked to inactivation of the H19 gene in 2 hepatoblastomas. However, 2 sporadic cases demonstrated monoallelic expression of the IGF2 gene with inactivation of the H19 gene. Our results suggest that H19 may play a role as a common imprinted tumor suppressor gene in "sporadic" hepatoblastomas but may at times work independently of IGF2 expression.

Child↗

PubMed1999

Terminology and morphologic criteria of neuroblastic tumors: recommendations by the International Neuroblastoma Pathology Committee.

BACKGROUND: As part of the international cooperative effort to develop a complete set of International Neuroblastoma Risk Groups, the International Neuroblastoma Pathology Committee (INPC) initiated activities in 1994 to devise a morphologic classification of neuroblastic tumors (NTs; neuroblastoma, ganglioneuroblastoma, and ganglioneuroma). METHODS: Six member pathologists (H.S., I.M.A., L.P.D., J.H., V.V.J., and B.R.) discussed and defined morphologically based classifications (Shimada classification; risk group and modified risk group proposed by Joshi et al.) on the basis of a review of 227 cases, using various pathologic characteristics of the NTs. The classification-grading system was evaluated for prognostic significance and biologic relevance. RESULTS: The INPC has adopted a prognostic system modeled on one proposed by Shimada et al. It is an age-linked classification dependent on the differentiation grade of the neuroblasts, their cellular turnover index, and the presence or absence of Schwannian stromal development. Based on morphologic criteria defined in this article, NTs were classified into four categories and their subtypes: 1) neuroblastoma (Schwannian stroma-poor), undifferentiated, poorly differentiated, and differentiating; 2) ganglioneuroblastoma, intermixed (Schwannian stroma-rich); 3) ganglioneuroma (Schwannian stroma-dominant), maturing and mature; and 4) ganglioneuroblastoma, nodular (composite Schwannian stroma-richlstroma-dominant and stroma-poor). Specific features, such as the mitosis-karyorrhexis index, the mitotic rate, and calcification, were also included to allow the prognostic significance of the classification to be tested. Recommendations are made regarding the surgical materials to use for an optimal pathobiologic assessment and the practical handling of samples. CONCLUSIONS: The current article covers the essentials and important points regarding the histopathologic evaluation of NTs. Using the morphologic criteria described herein, the INPC is proposing the International Neuroblastoma Pathology Classification. It is reported in a companion article in this issue (Cancer 1999;86:363-71).

Biometry↗

PubMed1999

The International Neuroblastoma Pathology Classification (the Shimada system).

BACKGROUND: The International Neuroblastoma Pathology Committee, which is comprised of six member pathologists, was convened with the objective of proposing a prognostically significant and biologically relevant classification based on morphologic features of neuroblastic tumors (NTs) (i.e., neuroblastoma, ganglioneuroblastoma, and ganglioneuroma). METHODS: A total of 227 cases were reviewed. Consensus diagnoses from morphologic features (criteria described separately) based on five of six or six of six agreements by the reviewer pathologists were used for prognostic analysis. Prognostic effects of morphology, both individual and in combination, taken in conjunction with age (Shimada classification, histologic grade, and risk group), were analyzed. RESULTS: Approximately 99% of cases (224 of 227) had consensus diagnoses for categorization: neuroblastoma (Schwannian stroma-poor), 190 cases; ganglioneuroblastoma, intermixed (Schwannian stroma-rich), 5 cases; ganglioneuroma (Schwannian stroma-dominant) maturing, 1 case; ganglioneuroblastoma, nodular (composite Schwannian stroma-rich/stroma-dominant and stroma-poor), 19 cases; and NT-unclassifiable, 9 cases. For the NTs, subtype (93% consensus: undifferentiated, 6 cases; poorly differentiated, 155 cases; and differentiated, 15 cases), mitosis-karyorrhexis index (90% consensus: low, 94 cases; intermediate, 40 cases; and high, 37 cases), mitotic rate (75% consensus: low, 89 cases; high, 50 cases; and not determined, 4 cases), and calcification (100% consensus: yes, 110 cases and no, 80 cases) were recorded. Statistical analysis demonstrated that the Shimada classification system (90% consensus; 3-year event free survival: 85% for the group with favorable histology and 41% for the group with unfavorable histology; P = 0.31 x 10(-9)) had a significantly stronger prognostic effect than individual features and other combinations. CONCLUSIONS: The International Neuroblastoma Pathology Classification, a system based on a framework of the Shimada classification with minor modifications, is proposed for international use in assessing NTs.

Brain Neoplasms↗

PubMed1999

Effect of storage temperature on cell viability in cryopreserved canine aortic, pulmonic, mitral, and tricuspid valve homografts.

We determined how long cryopreserved aortic, pulmonic, mitral, and tricuspid valve homografts could be stored in a deep freezer (-80 degrees C) without compromising fibroblast viability. Valves harvested from 20 anesthetized mongrel dogs were grouped into nonfrozen control, frozen and stored in liquid nitrogen (-196 degrees C), and frozen and stored in a deep freezer (-80 degrees C). Frozen groups were divided into subgroups and stored for 2, 4, 8, or 12 weeks. A leaflet of each valve was divided into three fragments, and fibroblast viability was analyzed by flow cytometry. Cell viability was defined as staining by fluorescent diacetate but not by propidium iodide. The viability of untreated control valves from all four sites was about 70%, decreasing to about 50% when treated with low doses of antibiotics. The viability of frozen valves stored in liquid nitrogen was about 45% without a significant difference among storage periods. The viability of valves frozen and stored in a deep freezer was significantly lower than for the liquid nitrogen group at 2 weeks for the mitral valve and at 4 weeks for other valves. These results suggest that homografts can be stored in a deep freezer for up to 2 weeks without deterioration.

Animals↗

PubMed1999

Appearance of cytokine-induced neutrophil chemoattractant isoforms and immunolocalization of them in lipopolysaccharide-induced acute lung inflammation in rats.

OBJECTIVE AND DESIGN: Recently, rat cytokine-induced neutrophil chemoattractant (CINC), which belongs to the interleukin-8 family, was grouped into four isoforms, CINC-1, CINC-2a, CINC-2beta, and CINC-3. To determine the major component and the source of CINC in airways, we investigated the change in appearance of CINC isoforms after exposure of rats to lipopolysaccharide. METHODS: Male Sprague-Dawley rats, 8-10 weeks old, were used in the present study. Bronchoalveolar lavage (BAL) was performed at 1, 2, 4, 6, 12, and 24 h after lipopolysaccharide inhalation (4 mg/ml for 30 min). The concentrations of each specific rat CINC in the BAL supernatant were measured by use of commercially available kits. Furthermore, lung tissue was employed for immunohistochemical staining of CINCs (CINC-1, -2alpha,-2beta, and -3) using the streptavidin-biotin technique. RESULTS: Inhalation of lipopolysaccharide caused increases in CINC-1, CINC-2aalpha, and CINC-3 in BAL fluids, whereas CINC-2beta was not detected. The increases in CINC-2a and CINC-3 were less than the increase in CINC-1. Positive immunohistochemical staining for CINC-1 was detected in bronchial noncilliated cells and in certain neutrophils that had infiltrated into the submucosa. CONCLUSIONS: These findings suggest that CINC-1 is the major isoform among the four CINCs in lipopolysaccharide-induced acute lung inflammation in rats. Its sources are likely to be bronchial noncilliated cells and certain infiltrating neutrophils.

Animals↗

PubMed1999

Apoptosis and remodelling of beta cells by paracrine interferon-gamma without insulitis in transgenic mice.

AIMS/HYPOTHESIS: To examine whether interferon-gamma destroys islet beta cells directly or indirectly through lymphocyte activation, or whether direct action of interferon-gamma on beta cells by itself induces diabetes without insulitis. METHODS: To avoid possible nonspecific breakdown of beta cells by transgenic overexpression of interferon-gamma by the insulin promoter, we generated transgenic mice expressing interferon-gamma under the control of rat glucagon promoter (RGP-IFN-gamma-Tg mice). RESULTS: The absence of insulitis in RGP-IFN-gamma-Tg mice enabled us to investigate the direct effects of paracrine interferon-gamma. In RGP-IFN-gamma-Tg mice, serum concentrations of interferon-gamma and tumour necrosis factor-alpha (TNF-alpha) were 50 and 6 times higher than those in their littermates, respectively, and glucose-responsive insulin secretion decreased to one-half the level of that in the littermates. Transgenic interferon-gamma induced remodelling of beta cells where apoptosis of many beta cells was compensated by their vigorous regeneration and diabetes did not occur in most of the RGP-IFN-gamma-Tg mice. CONCLUSION/INTERPRETATION: Interferon-gamma alone is insufficient for the complete destruction of beta cells in vivo, and factors other than interferon-gamma including activated lymphocytes or other cytokines, are necessary in addition to interferon-gamma for the development of Type I (insulin-dependent) diabetes mellitus.

Animals↗

PubMed1999

Human acute myeloblastic leukemia-ascites model using the human GM-CSF- and IL-3-releasing transgenic SCID mice.

To generate an appropriate model for human acute myeloblastic leukemia (AML), we have successfully established a human hematopoietic growth factor-dependent AML cell line (TF-1 and UT-7/GM)-ascites model using human granulocyte-macrophage colony-stimulating factor (hGM-CSF)- and human interleukin 3 (hIL-3)-releasing transgenic (Tg)-SCID mice. When 1 x 10(7) cells of TF-1, a human erythroleukemia cell line, were transplanted into the peritoneum of irradiated Tg-SCID mice (TF-1 ip/Tg-SCID mice), TF-1 cells grew in both the single cell suspension form (asTF-1) and solid form in ascites and invaded various tissues: lungs, liver, pancreas, and genitals, 3-6 weeks following transplantation. Subsequently, 0.5-1 x 10(7) cells of UT-7/GM, a subline of the UT-7 human megakaryoblastic leukemia cell line, grown in the back of hGM-CSF Tg-SCID mice after subcutaneous inoculation, were transplanted into the peritoneum of other irradiated hGM-CSF Tg-SCID mice. After 4 weeks, UT-7/GM cells (asUT-7/GM) also grew in the same manner as TF-1 cells in hGM-CSF Tg-SCID mice. Analysis of the cells from the peritoneum and tissues by PCR amplifying ALU and human GM-CSF receptor beta sequences and by immunohistochemical staining using anti-human CD45 revealed that they possessed the original characteristics of the parental cells. To confirm the usefulness of this human AML-ascites model, experimental treatment of AML cells grown in these mice was carried out with a differentiation inducer, delta-aminolevulinic acid (deltaALA), which induces hemoglobin synthesis for TF-1 in vitro and is thus regarded as an anti-leukemia drug candidate. Unexpectedly, growth promotion of TF-1 cells was observed in the treated TF-1 ip/hIL-3 Tg-SCID mice without differentiation to erythroid cells after treatment with delta-ALA (5 mM) for 7 days. These results indicate that Tg-SCID mice can support the growth of human hematopoietic growth factor-dependent AML cell lines which are usually rejected by SCID mice, without modification of the parental cell characteristics. In addition, this Tg-SCID leukemia-ascites model may become a useful preclinical tool for estimation of drug efficacy in vivo, since the drug candidate which was promising in vitro did not act in the same manner in vivo.

Aminolevulinic Acid↗

PubMed1999

Nephrotic syndrome and end-stage renal disease with WT1 mutation detected at 3 years.

We report a boy who presented at 3 years with nephrotic syndrome and end-stage renal failure. Although histopathological findings showed end-stage kidney, isolated diffuse mesangial sclerosis (IDMS) was suspected because of his clinical course, and was confirmed by the presence of WT1 (Wilms tumor suppressor gene) mutation. He did not have ambiguous genitalia or Wilms tumor. The karyotype was 46:XY. A constitutional mutation in exon 7 (953G-->A, 312Arg-->Gin) was detected. A few cases of male IDMS, associated with WT1 mutations, have been reported. We believe that investigation for the WT1 mutation should be performed not only in Denys-Drash syndrome and IDMS, but also in end-stage renal disease with unexplained nephrotic syndrome of early onset. WT1 mutation-associated nephrotic syndrome has an increased risk of Wilms tumor. Careful ultrasound evaluations or bilateral nephrectomies are indicated.

Child, Preschool↗