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Biomedical subjects

K Uematsu

Publications and source records attributed to K Uematsu.

At least 55 records · Page 3Linked to original sources
PubMed1998

Pathological changes in glandular stomach of Helicobacter pylori-infected Mongolian gerbil model.

We have established a Helicobacter pylori-infected Mongolian gerbil model, following Hirayama's method, to clarify gastric diseases associated with H. pylori infection. We administered the culture broth of H. pylori ATCC 43504 orally to 8-week-old male Mongolian gerbils. After H. pylori inoculation, the gerbils were fed in a vinyl isolator. Subsequently, over the course of 48 weeks, they were killed for histopathological examination, H. pylori culture, and serum antibody measurement. H. pylori colonization in the glandular stomach was seen in all the infected gerbils, but only a few H. pylori were detected histologically. The serum antibody titer in the H. pylori-inoculated group increased gradually in comparison with controls. Acute inflammation, immature epithelium, and erosion were observed 2 weeks after H. pylori infection. Chronic inflammation was noted from 4 weeks after H. pylori infection. We also found intestinal metaplasia and gastric ulcers from 12 and 24 weeks after inoculation, respectively. Some histological findings were similar to those in humans, but the chronic inflammation in the gerbils was present mainly in the deep mucosa and submucosa. This appears to be a good animal model for H. pylori-associated gastric diseases and it may be useful for investigating the pathogenesis of H. pylori infection.

Animals↗
PubMed1997

Identification of the midbrain locomotor nuclei and their descending pathways in the teleost carp, Cyprinus carpio.

In order to identify the mesencephalic spinal pathways for initiation of swimming in the carp, we employed electrical and chemical microstimulation of the mesencephalic tegmentum. Electrical stimulation of the midbrain in decerebrate carp produced bilateral or unilateral rhythmic movements of the tail. Bilateral alternating movements were induced by stimulation with the lowest threshold currents to the brain region just beneath the third ventricle at the level of the mid mesencephalon. The region included the nucleus of medial longitudinal fasciculus (Nflm), the medial longitudinal fasciculus (flm), the red nucleus (Nrb). To specify the nuclei of the origin of the descending pathway, we microinjected 0.1 M L-glutamic acid to the region. Both bilateral and unilateral tail movements were induced, the majority being the latter. The unilateral movements were accompanied with tail flips toward the ipsilateral side of stimulation sites. The smallest injection volume required for initiation of the movement was recorded at the Nflm. Bilateral tail movements were produced only by injections into the medial region between the nucleus of the both sides. The present results imply a crucial role of Nflm neurons in the initiation of swimming Nflm neurons on one side project through flm to the ipsilateral spinal cord along its entire length and regulate activities of the individual central pattern generators.

Animals↗
PubMed1997

Contribution of cell proliferative activity to malignancy potential in testicular seminoma.

Testicular anaplastic seminoma, which has a high mitotic activity, is regarded as more malignant than typical seminoma, although its prognosis is still unclear. To determine whether seminoma with relatively greater malignancy potential can be identified based on the cell proliferative activity, the mitotic rate (MR; mitotic count per high-power field), mitotic index (MI; mitotic count per 1000 cells), Ki-67 labeling index (Ki-67 LI; the percentage of positive cells) and proliferating cell nuclear antigen LI (PCNA LI; the percentage of positive cells) were histologically examined in 44 patients. The MI, Ki-67 LI and PCNA LI in patients with metastatic disease were significantly higher than those in patients without metastatic disease, and the MI in patients with fatal disease was significantly higher than those in patients cured of the disease. However, these distributions of the MI, Ki-67 LI and PCNA LI values overlapped for both pairs of groups. There were no significant differences in the MR. These results suggest that the cell proliferative activity makes a small contribution to the malignancy potential in testicular seminoma, with the activity being not necessarily indicative of metastasis and prognosis.

Adolescent↗
PubMed1997

Immunohistochemical analysis of the nm23 gene products in testicular seminoma.

The nm23 gene has been identified as a metastasis suppressor gene. To clarify the role of nm23 as a metastasis suppressor gene in testicular seminoma, the expression of the nm23-H1 and -H2 proteins (human nucleoside-diphosphate kinase-A and -B) was immunohistochemically examined in 43 patients. Thirty-six (84%) and 21 (49%) of the 43 primary tumors were positive for the nm23-H1 and -H2 proteins, respectively. There was no significant difference in either nm23-H1 or -H2 expression between the 24 primary non-invasive tumors and the 19 primary invasive tumors, or between the 31 primary tumors without metastasis and the 12 primary tumors with metastasis. In all, and 5 of 6 metastatic tumors, the expression of nm23-H1 and -H2 proteins was observed, respectively, and the expression was not decreased in the metastatic tumors, compared to the primary tumors. In conclusion, the immunohistochemical expression of both the nm23-H1 and -H2 gene products is not associated with the metastatic status or the invasive status of testicular seminoma, and it is unlikely to be a useful non-metastatic indicator for testicular seminoma. Further studies are needed to elucidate the biological role of nm23.

Adolescent↗
PubMed1997

Testicular seminoma with human chorionic gonadotropin production.

Testicular seminoma with elevated serum human chorionic gonadotropin level (hCG-positive seminoma) is regarded as more malignant than marker-negative seminoma, although its prognosis is still unclear. To clarify the malignant potential of seminoma with hCG production, the serum levels of the beta subunit of hCG (beta-hCG) and lactic acid dehydrogenase (LDH) were examined in 35 and 40 patients, respectively, and the immunohistochemical expression of beta-hCG examined in 45 tumors. The elevation of the LDH serum level correlated to the invasive status, metastatic status and poor outcome, while that of the serum beta-hCG level correlated only to the metastatic status. Immunohistochemical expression of beta-hCG was observed in syncytiotrophoblastic giant cells in 11 tumors and a few mononuclear seminoma cells in 36 tumors. Expression was not associated with the malignancy potential, except where the expression in mononuclear cells inversely correlated to the invasive status. These results suggest that most seminomas produce a slight amount of hCG; that an elevated hCG serum level indicates the presence of metastatic tumors and mainly reflects an increase in tumor volume but not in cellular malignancy potential; and that the LDH serum level, rather than hCG, is more useful as a prognostic indicator for patients with seminoma.

Adolescent↗
PubMed1997

The role of three-dimensional computed tomography in the management of maxillofacial bone fractures.

The findings of three-dimensional computed tomography (3DCT) and two-dimensional computed tomography (2DCT) with helical CT scanning were compared for 21 patients with maxillofacial bone fractures. The results of this study suggest that the 3DCT evaluation can be divided into 3 groups. The first group, in which 3DCT is superior to 2DCT, includes severe complicated midface fractures, for example, tripod fractures and complicated maxillary bone fractures. The second group, in which 3DCT is equal to 2DCT, includes simple fractures, for example, nasal bone fractures and isolated zygomatic fractures. In this group, patients and their families could easily understand the nature of the fracture and clinical course shown by 3DCT as compared with conventional X-ray and 2DCT. The third group, in which 3DCT is inferior to 2DCT, includes blowout fractures. Although 3DCT does not provide additional information is blowout fractures, helical scanning permits clear observation of multiplanar images without artifacts arising from metal prostheses by excluding lower slices during image reconstruction. We conclude that 3DCT provides useful information, especially in regard to the extent of complex fracture lines, as in tripod fractures.

Fractures, Bone↗
PubMed1997

Effective treatment with low-dose methotrexate pulses of a child of mixed connective tissue disease with severe myositis refractory to corticosteroid.

A 13-year-old girl with mixed connective tissue disease (MCTD) was described. She visited our hospital with recurrent parotid gland swelling, arthritis, and myositis. Sclerodactyly and Raynaud's phenomenon were also defined, and the laboratory findings of high titers of antinuclear antibody (speckled type), positive anti-RNP antibody, positive rheumatoid factor, and hypergammaglobulinemia suggested the diagnosis of MCTD associated with Sjögren syndrome. The muscle weakness and the increased levels of CK prompted us to examine the muscle biopsy and to perform the electromyography, both of which suggested severe muscle inflammation. The siarography and lip biopsy indicated definitively the association of Sjögren syndrome. Corticosteroid therapy including methyl-prednisolone pulses was started, but the effects were limited. The addition of low-dose methotrexate effectively lowered the levels of CK, and gradually improved the muscle strength. Thus, low-dose methotrexate therapy is recommended to the patients with MCTD who have severe myositis refractory to corticosteroid.

Adolescent↗
PubMed1997

A new T-lymphocyte cloning assay for detection of in vivo mutations in the human hypoxanthine-guanine phosphoribosyltransferase gene.

The X-linked hypoxanthine-guanine phosphoribosyl transferase (hprt) gene is a target of analyses of in vivo mutation frequencies in circulating T-lymphocytes. We established a novel, accessory cell-free cloning method of T-lymphocytes with a hprt mutation by a combined use of recombinant interleukin-2, conditioned medium from activating T-lymphocytes and culture plates coated with anti-CD3 monoclonal antibody. Using the method, we examined mutation frequencies of the hprt gene in T-lymphocytes from six healthy individuals, nine patients with colon cancer including two patients from different families with hereditary nonpolyposis colon cancer and six cancer-free relatives of the patients. In six healthy individuals, the mean cloning efficiency and mutation frequency (MF) of the hprt gene in T-lymphocytes were 0.51 +/- 0.28 and 9.4 +/- 7.5 x 10(-6), respectively. These data were similar to the reported values. The mean MFs in the nine colon cancer patients (10.6 +/- 7.3 x 10(-6)) were not significantly different from those of the 12 cancer-free individuals (11.6 +/- 9.4 x 10(6)). The correlation between mutation frequencies and age of the individuals was significant regardless of the presence or absence of cancers. The single-strand conformation polymorphism analyses of nested RT-PCR products of hprt mRNA were done in 33 mutant clones from five members of a family of which MF values were high. All the analyzed mutant clones show a genetic aberration in the coding region of the hprt gene. At least 28 of 33 mutants were independent. Our method provides a new versatile tool for in vivo analysis for mutations of the hprt gene.

Adult↗
PubMed1996

Prenatally detected hepatic hamartoma: another cause of non-immune hydrops.

Although various conditions associated with non-immune hydrops have been reported, primary hepatic tumours are rare. As a mesenchymal hamartoma of the liver is a rare benign tumour, it has not been listed as a cause of hydrops. In this report we describe a case in which a large cystic mass in the fetal liver associated with non-immune hydrops was prenatally detected with sonography and magnetic resonance imaging, and histopathologically confirmed as a mesenchymal hamartoma of the liver.

Adult↗
PubMed1996

Morphogenesis of the brain in larval and juvenile Japanese eels, Anguilla japonica.

We compared the morphology, including relative volumes (RV), of some brain regions in leptocephalus larvae (10-30 mm in total length), glass eels (elvers), young, and immature pre-adults of the Japanese eel Anguilla japonica. The external brain shape of the leptocephali gradually changes from a laterally compressed one to a depressed elongated one. These changes are fundamentally due to biased growth of the telencephalon and optic tectum. The dramatic brain transformation progresses until the juvenile stage and culminates in an adult-type brain arrangement, with a developed cerebellum and eminentia granularis and a much more flattened appearance. The RVs of brain regions closely related to somatic sensory functions are quite different in larvae and juveniles. The larvae possess larger optic tecta and smaller chemo- and mechanosensory regions than the juveniles. The RV of the olfactory bulb increases, and that of the optic tectum decreases, until the adult stage, unlike the condition in a pelagic fish, Pagrus major, suggesting that adult eels are inferior to pelagic fishes in visual perception. In contrast, the brain morphology of the larvae suggests that they are equipped with a well-developed visual system, while the functional significance of the system still remains a mystery. It might be important for feeding, orientation and diurnal vertical migration of the larvae.

Anguilla↗
PubMed1996

Detection of microsatellite instability in cancers by arbitrarily primed-PCR fingerprinting using a fluorescently labeled primer (FAP-PCR).

The microsatellite mutator phenotype (MMP), detected as a change in the number of repeating units in hundreds of thousands of microsatellite sequences in the tumor cell genome, underlies the carcinogenesis of a variety of tumors including sporadic and hereditary nonpolyposis colon cancers. This enhanced microsatellite instability was discovered using arbitrarily primed polymerase chain reaction (AP-PCR) fingerprinting of DNA from colon cancers. In this study, we found an arbitrary primer that can amplify multiple DNA fragments containing repeated sequences, including the poly A tracts found in the Alu repeats of the human genome. The combined use of primer labeling with fluorescence and an automated DNA sequencing analysis of AP-PCR products (FAP-PCR) detected alterations in fingerprint bands in all DNA samples previously determined to belong to the MMP. Fluorescent AP-PCR fingerprinting using this single arbitrary primer provides a convenient and efficient method for detecting tumor specific fingerprint alterations that are usually undetectable by conventional fingerprinting.

Blotting, Southern↗
PubMed1996

Carcinoid tumor of the gall bladder.

A classical carcinoid tumor, measuring 11 x 17 mm, was found in a 41-year-old woman in the neck of the gall bladder. The lesion infiltrated the muscular layer of the gall bladder wall. Histologically, the tumor was positive for only Grimelius and chromogranin A stains. In a literature search, approximately half of the tumors reported as gall bladder carcinoid tumor appear to be actually endocrine cell carcinomas, which are completely different from classical carcinoid tumors with respect to size, metastasis and prognosis. These carcinomas should not be termed as carcinoid tumors from both the clinical and histological points of view, and should be clearly distinguished from benign lesions when reported.

Adult↗
PubMed1995

Spinal and parachordal neurons in the eel leptocephali, Anguilla japonica revealed by labeling with a fluorescent dye.

The spinal and parachordal neurons innervating the trunk muscles and skin in the Japanese eel leptocephali, Anguilla japonica, were retrogradely labeled with a fluorescent dye, DiI (1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate). The spinal motoneurons innervating the trunk muscles were located in the medioventral part of the spinal cord and were divided into two populations on the basis of their soma sizes and position. The sensory neurons were labeled in the well-developed dorsal root ganglia, that were situated just peripheral to the meeting of the dorsal and ventral roots. Presumable postganglionic sympathetic neurons were also labeled in the sympathetic ganglia which were located ventrally to the notochord. Thus, the spinal and parachordal neurons innervating the trunk muscles and skin were firstly identified in the anguilliform leptocephalus.

Anguilla↗
PubMed1995

[Giant cell interstitial pneumonia in a metal grinder with an abnormally high level of serum CA19-9].

Interstitial pneumonia and recurrent pneumothorax developed in a 48-year-old man who had worked as a metal grinder. He died of respiratory failure despite having received antibiotics and steroids, and despite having undergone pleural sclerosis therapy. Giant cell interstitial pneumonia was diagnosed; innumerable bizarre giant cells engulfing black granules were found within the alveoli. The results of high-energy dispersion X-ray microanalysis indicated that the patient had hard metal pneumoconiosis associated with tungsten in the black granules. When he was admitted to the hospital, his serum CA19-9 and SLEX concentrations were abnormally high (2600 and 200 ng/ml, respectively). Immunohistochemical analysis of lung tissue was done with anti-CA19-9 and SLEX antibodies. CA19-9 staining revealed strong bronchialization and squamous metaplasia in contrast to type II hyperplasia. SLEX staining showed strong type II hyperplasia. Further investigations will be needed to determine the mechanism of elevated tumor-associated carbohydrate antigens in serum.

Biomarkers, Tumor↗
PubMed1994

Brain morphogenesis of the red sea bream, Pagrus major (teleostei).

Post-embryonic morphogenesis and regional volumetric growth of the brain in larval and juvenile red sea bream, Pagrus major, were analyzed by employing a computer-aided three-dimensional reconstruction of serial sections of the head. The relative volume of the optic tectum rapidly increases after hatching until day 8, implying the importance of the visual sense for the first feeding, which begins on day 4. The differentiation and outgrowth of the primary gustatory center in the medulla after day 43 may reflect the increasing number of taste buds, suggesting a relationship to the onset of benthic feeding as juveniles. The rather rapid increases in the relative volumes of the corpus and valvula cerebelli after day 28 and their progressive morphogenesis may be correlated with improved motor performance. The relative volumes of the octaval-lateral line centers, including the eminentia granularis and the crista cerebellaris, and the relative volume of the torus longitudinalis, increase in parallel with those of the corpus and valvula cerebelli.

Animals↗
PubMed1994

[Adrenal hepatoid carcinoma producing alpha-fetoprotein: a case report].

A case of left adrenal hepatoid carcinoma is reported. The patient was a 57-year-old male and his chief complaint was general fatigue. Preoperative laboratory data showed markedly increased levels of alpha-fetoprotein (AFP) (30,500 ng/ml) and PIVKA-II (3.01 AU/ml). Both computed tomography (CT) and magnetic resonance computed tomography (MRCT) showed left adrenal tumor (8 x 5 cm). Angiography showed hypervascular tumor over the upper pole of the left kidney. Thoracoabdominal nephro-adrenalectomy was performed. Histological examination demonstrated hepatoid carcinoma of the left adrenal gland. AFP was positive in the tumor cells. The levels of both AFP and PIVKA-II dropped to the normal range postoperatively. Hepatoid carcinoma in the urological field is very rare. As hepatoid carcinoma in the Japanese literature in the urological field, there were only 4 cases of renal tumor, 2 cases of renal pelvic tumor, 2 cases of retroperitoneal space and 1 case of urachal tumor. This is the first report of adrenal hepatoid carcinoma in Japan.

Adenocarcinoma↗
PubMed1994

[A case of capillary hemangioma of the testis in a child].

Testicular tumors derived from connective tissue, blood vessels and musculature are uncommon and intratesticular tumors of vascular origin are extremely rare. A rare case of capillary hemangioma of the testis in a child is reported. An 11-year-old boy was admitted with the chief complaint of painless mass in the right scrotum. He was diagnosed with a right testicular tumor by physical examination and ultrasonography, preoperatively. Right high orchiectomy was done on December 10, 1990. The testis measured 2.5 x 2.3 x 1.5 cm. Pathologically, the tumor was diagnosed as a capillary hemangioma of the testis.

Child↗