Biomedical subjects

Y Furuta

Publications and source records attributed to Y Furuta.

At least 127 records · Page 7Linked to original sources

PubMed1991

[Early diagnosis of acute mesenteric artery occlusion--clinical and experimental study].

This study was undertaken for the purpose of making early diagnosis of acute superior mesenteric artery occlusion (SMAO). (Clinical Study) This study included 16 patients with SMAO. The early diagnoses by clinical, laboratory, echographic and radiologic findings which were commonly obtained in the cases of abdominal emergency, were difficult. Angiography was useful method for its diagnosis. But in its early stage, we could hardly determine which patient was subject to angiography, therefore non-invasive and simple screening modelity is needed for its early diagnosis. (Experimental Study) Portal blood flow (PVF) is considered to decrease when superior mesenteric artery (SMA) is occluded, because SMA is a main feeder of portal vein. If SMAO has specific portal hemodynamics, its early diagnosis will be possible by non-invasive PVF measurement using an ultrasonic duplex system (PD). We investigated the portal hemodynamic changes in experimental SMAO, peritonitis and ileus using 24 mongrel dogs. Our results showed that PVF to cardiac output ratios (PCR) of SMAO models were under 10% and in contrast, those of others were over 10%. So SMAO models were distinguishable from others. These suggested that PCR measured by PD and echocardiography was an useful indicator of early diagnosis of SMAO.

Acute Disease↗

PubMed1990

Dependence of indomethacin-induced potentiation of murine tumor radioresponse on tumor host immunocompetence.

In a previous study (Furuta, Y., Hunter, N., Barkley, H. T., Jr., Hall, E., and Milas, L., Cancer Res., 48:3008-3013, 1988), we demonstrated that inhibition of prostaglandins in murine tumors by indomethacin results in the augmentation of tumor response to single doses of ionizing radiation. The results of the present study show that indomethacin augmented tumor response to fractionated irradiation as well, the enhancement factor being more than 2. The effect of indomethacin on tumor growth and on tumor radioresponse was assayed in normal mice, mice deficient in T-cells (nude mice), and mice whose general immunocompetence was suppressed by whole-body irradiation. The antitumor activity of indomethacin was not significantly influenced by the immunocompetence of the tumor host. Since indomethacin inhibited tumor neoangiogenesis, we postulated that this inhibition is a major mechanism responsible for the antitumor activity of indomethacin. In contrast, potentiation of tumor radioresponse by indomethacin was greatly dependent on immunocompetence of tumor host: it was significantly reduced, or even abolished, when tumor grew in nude and whole-body irradiation mice. Thus, while immunocompetence of the tumor host has no significant effect on antitumor action by indomethacin, it plays a decisive role in the potentiation of tumor radioresponse by indomethacin.

Animals↗

PubMed1990

Postoperative angiographic evaluation of gastroepiploic artery grafts: technical considerations and short-term patency.

Follow-up angiography was performed in 37 patients with right gastroepiploic artery (GEA) grafts at 27 +/- 32 days postoperatively. By the femoral approach, a 5F cobra or twist catheter was advanced selectively into the gastroduodenal artery (GDA) over a plastic-coated guidewire. In 29 patients, the GDA was successfully catheterized, and the GEA grafts were clearly visualized by the injection of 3-7 ml of contrast medium. GDA catheterization was unsuccessful in 8 patients, but in 4 of them the grafts were well visualized when 15-20 ml of contrast was injected. In the other 4 patients, visualization of the GEA grafts was poor, but the distal portions were outlined by retrograde perfusion from the native right coronary arteries. A total of 34 GEA grafts were patent (92%), and the diameters of these grafts were adequate when compared with respective recipient coronary arteries (2.8 +/- 0.9 and 2.3 +/- 0.6 mm, respectively; P less than .05). No complications were noted except for transient vasospasm (3 patients) in the GEA, hepatic artery, or both, which was relieved by the intra-arterial injection of isosorbide dinitrate (2.5 mg). Thus, the over-the-wire technique allows simple and safe GDA catheterization, which is essential for obtaining good visualization of GEA grafts.

Adult↗

PubMed1990

Env-derived gp55 gene of Friend spleen focus-forming virus specifically induces neoplastic proliferation of erythroid progenitor cells.

A group of retroviruses carrying truncated viral genes has recently been suggested as the cause of new patterns of diseases. One such virus is the replication defective component of the Friend murine leukemia virus (F-MuLV) complex, called Friend spleen focus forming virus (F-SFFV). This virus induces erythroblastosis, and a virion envelope-related glycoprotein, gp55, encoded by F-SFFV has been suggested as the pathogenic gene. The role of the gp55 gene is, however, yet unclear in the apparently multistep erythroleukemogenesis. By separately producing transgenic mice harboring the whole F-SFFV DNA, the gp55 gene alone under the control of the retroviral long terminal repeat (LTR) and the gp55 gene under the control of cytoplasmic beta actin transcriptional regulatory unit, we show here that the gp55 gene is capable of inducing neoplastic proliferation of erythroid progenitor cells specifically in the absence of helper virus and other F-SFFV sequences. Under the control of the viral LTR the gp55 expression was detected only in leukemic tissues, but under the control of cytoplasmic beta-actin regulatory sequences, the gp55 was also expressed in a variety of normal tissues including preleukemic normal spleens. The development of erythroleukemia was suppressed under the genetic background of C57B1/6 mouse (resistant to F-MuLV; Fv-2rr), and required additional events even under the background of DDD mouse (susceptible to F-MuLV; Fv-2ss). The p53 and Spi-1 genes were frequently aberrant in transplanted tumors and cell lines derived from them, but were not in primary leukemic spleens.

Animals↗

PubMed1990

Induction of a variety of tumors by c-erbB2 and clonal nature of lymphomas even with the mutated gene (Val659----Glu659).

The c-erbB2 gene is expressed uniquely in fetal epithelium in vivo and has been suggested to contribute to the development and/or progression of adenocarcinomas in man. In order to assess the oncogenicity of the c-erbB2 gene in vivo, normal c-erbB2 and mutant c-erbB2 encoding glutamic acid instead of valine at position 659 within the transmembrane domain were introduced into mice under the transcriptional regulatory unit of mouse mammary tumor virus long terminal repeat (MMTV-LTR) or immunoglobulin enhancer--SV40 early gene promoter (Ig/Tp). In transgenic mice with normal c-erbB2 under MMTV-LTR, not only adenocarcinomas but also a variety of tumors including B lymphomas were induced at relatively late onset. Induction of pre-B cell lymphomas with normal c-erbB2 was also observed using the Ig/Tp regulatory unit within 6-10 months in some members of one transgenic family among seven lines established. In contrast, with the mutant c-erbB2 under the Ig/Tp regulatory unit, the lymphoma was induced neonatally in all members of four transgenic families among ten lines obtained. However, the immunoglobulin heavy chain gene rearrangement pattern indicated that even with the mutant c-erbB2 the induced lymphomas were clonal.

Adenocarcinoma↗

PubMed1990

Detection of activated c-H-ras oncogene in hepatocellular carcinomas developing in transgenic mice harboring albumin promoter-regulated simian virus 40 gene.

Hepatocellular carcinomas (HCCs) developing in transgenic mice harboring an albumin promoter-regulated simian virus 40 (SV40) tumor antigen gene were analyzed for activating point mutations of the c-H-ras oncogene. Oligonucleotide hybridization studies utilizing enzymatically amplified DNA sequences of paraffin-embedded tumor tissues revealed that 10 out of 25 HCCs contained either an A-to-T or an A-to-G conversion at the second position of codon 61. Northern blot studies confirmed expression of SV40 gene mRNAs in the tumor tissues of both mutation-positive and mutation-negative HCCs. These findings in association with earlier results thus strongly suggest that mutational activation of cellular oncogene may play an important role in SV40-initiated multistage hepatocarcinogenesis in vivo.

Albumins↗

PubMed1990

In situ hybridisation with digoxigenin-labelled DNA probes for detection of viral genomes.

The applicability of a recently developed non-radioactive DNA labelling and detection method, which uses the digoxigenin (DIG) enzyme linked immunosorbent assay (ELISA) system, for the detection of viral infections in pathology specimens by in situ hybridisation, was examined. Its efficacy was compared with that of biotin and radioisotope labelling methods. Three cases of progressive multifocal leucoencephalopathy, two of verruca vulgaris, and seven cases of laryngeal papilloma were studied. The sensitivity of the DIG labelled probe was almost the same as that of a 35S-labelled probe in the dot-blot hybridisation test. Using in situ hybridisation with 35S-labelled and DIG labelled probes, the levels of the hybridised signals detected were similar. The biotin labelled probe was less sensitive, particularly in the cases of laryngeal papilloma. The DIG labelling and detection method was highly sensitive and applicable to the detection of viral infection by ISH, and is preferable to a radiolabelled probe, especially when in situ hybridisation is done in the pathology laboratory.

Biotin↗

PubMed1990

Surgical excision of familial cavernous angioma in the pontomedullary region--case report.

The authors report on a surgical case of cavernous angioma in the pontomedullary region. A 60-year-old male exhibited a progressive neurological deficit consisting mainly of bulbar paresis and cerebellar signs, without ictal episodes, and computed tomographic scans showed growth of the lesion over 3 years. On preoperative assessment, a glial tumor was suspected to coexist with a cavernous angioma. The vascular malformation was totally excised successfully. This case also revealed an unusual familial occurrence.

Brain Neoplasms↗

PubMed1990

[A study of developmental changes of Indian mandibles concerning development of weight, height, thickness and length of the mandible].

A total of 230 mandibles were classified into 7 groups 8 stages according to eruption phase, observing developmental changes from unerupted stage (Group A) to permanent dentition (Group G) 1. Development from Group A to deciduous dentition completion stage (Group C) was classified into 3 types. 1) Regarding height of mandibular ramus, height and weight of mandibular body, the increase from Group B where the deciduous central incisor erupts to Group C is greater that from Group A-B (type a). 2) As to coronoid process height, length of mandibular body, mandibular length and mandibular ramus width, equal increases were seen between Group A-B and B-C (type b). 3) Chin height and thickness of the mandibular body developed suddenly with the eruption of the deciduous central incisors. The increase is greater in Group A-B (type c). 2. They are classified according to size proportion in unerupted stage as compared to entire size. The classification are: 42%-33% (smaller), 50%-45% (medium), 70%-50% (bigger). 1) Type a is small at Group A and developed steadily after Group C. Development is greater, about 2.3-3 times. 3) Type b at Group A is larger than type a. It continuously developed after Group C. The developmental rate is about 2 times except the coronoid process height. 3) Type c is large at Group A. No development occurred after D1 stage when first molars erupt. Developmental rate is 1.4-1.85 times and smallest of the 3 types. 3. Developmental quantity: 1) Regarding total increase; The height of the mandibular ramus, the height of the mandibular ramus and coronoid process showed about 28-32 mm increase Group C accounted for 55%, Group C-D2 14%-17%, Group D2-G 30%-27% of the developmental increase. The mandibular ramus width showed increases of 14.43mm (74% at D1 stage) and subsequent increase was 7% between each group, showing equal increases. 2) Chin and mandibular ramus height showed increases of 14 mm. At Group C, development in chin height accounted for 67%. The mandibular body width increased 4.0mm-6.0mm at the foramen in m2/m2 and 6/6 portions. It reached 82%-100% in D1 stage. 3) An increase in mandibular body length and mandibular length was 50mm and 32mm, reaching 73% of the entire developmental amount by D1 stage.

Adolescent↗

PubMed1990

Radioprotection of hematopoietic tissues in mice by indomethacin.

We recently reported that indomethacin, an inhibitor of prostaglandin (PG) synthesis, increased the radioresponse of PG-producing murine tumors, but it protected the hematopoietic system from radiation damage [Furuta et al., Cancer Res. 48, 3008-3013 (1988)]. Here we have investigated possible mechanisms responsible for the radioprotective effect of indomethacin. In the exogenous spleen colony assay, bone marrow cells from indomethacin-treated mice showed a similar radioresponse to those from mice not treated with indomethacin, thus excluding true radioprotection as a mechanism. Also, neither the total number of bone marrow cells nor the number of stem cells in bone marrow were affected by the treatment with indomethacin. However, indomethacin induced significant splenomegaly, which was associated with an increased number of both nucleated cells and hematopoietic stem cells in the spleen. The latter was determined by the exogenous spleen colony assay. Thus indomethacin protected hematopoietic tissue indirectly through stimulation of hematopoietic cells in the spleen. When indomethacin was combined with WR-2721, which is a true radioprotector, we obtained a greater radioprotective effect than with either used alone according to the endogenous spleen colony assay.

Amifostine↗

PubMed1990

[Molecular pathologic study of human papillomavirus infection in inverted papilloma and squamous cell carcinoma of the nasal cavities and paranasal sinuses].

Nasal inverted papilloma (IP) is a rare benign tumor that involves the mucous membranes of the nasal cavity and paranasal sinuses. Postoperative recurrences of this tumor have been observed frequently, and an association with squamous cell carcinoma (SCC) has been described occasionally. The etiology of IP remains unknown, but some studies have suggested a possible causative role of human papillomavirus (HPV) in IP. To determine the etiological role of HPV in IP and SCC associated with IP, to clarify the relationship between HPV and malignant transformation of IP, and to study the possibility of HPV implication in SCC of the nasal cavities and paranasal sinuses, retrospective analysis of HPV infection was performed in the surgically resected specimens of inverted papilloma (n = 26, in which 7 patients had SCC) and SCC (n = 40) of the nasal cavities and paranasal sinuses. Pathologically, koilocytosis, which is known to be closely related to HPV infection, and epithelial atypia were investigated. To detect the HPV protein antigen or nucleic acids, immunohistochemical method and molecular pathologic techniques, or in situ hybridization (ISH) and polymerase chain reaction (PCR) of DNA extracted from paraffin embedded tissues were used. By ISH we detected HPV 11 DNA in three cases (12%) of IP and HPV 16 DNA in one case (4%) of IP with SCC. By PCR HPV16 was detected in 2 of 7 cases in which IP was associated with SCC. However, no protein antigen was detected in any cases of IP by immunostaining, and viral mRNA was not detected by the study of ISH after DNase digestion. Pathologically, there was a closed relationship between HPV infection and koilocytosis, and severe epithelial atypia was frequently seen in the cases of IP coexisted with SCC. But there was no clear relationship between HPV infection and recurrence of IP. In SCC, HPV 16 and HPV 18 were detected by PCR in 4 cases (10%) and in one case (2.5%), respectively. Thus, it was suggested that HPVs were involved in the development of IP in some cases (19%, 5/26), but the state of infection is somewhat different from other papillomatous lesions, such as genital condylomas or laryngeal papillomas. HPV 16 and HPV 18 were found to be related to the malignant transformation of IP and to the pathogenesis of SCC originated in the nasal cavities and paranasal sinuses.

Adult↗

PubMed1989

Onuf's motoneuron is resistant to poliovirus.

Onuf's nucleus, located in the anterior horn of the sacral spinal cord, has been shown to innervate the striated muscles of the urethral and anal sphincters and is known to be well preserved in patients who have motoneuron disease. To answer the question whether the nucleus is also safe from motoneurotrophic virus infections, we examined the spinal cords of 3 individuals who had suffered severe poliomyelitis. In 2 of these which were acutely fatal cases, all motoneurons were damaged by neuronophagia, but Onuf's nucleus escaped the inflammatory degeneration. In a chronic case, neuronal loss in the anterior horn with replacement by gliosis was prominent below the thoracic cord down to the sacral cord, but Onuf's nucleus was well preserved. Thus, Onuf's nucleus appears to differ from other motoneurons with regard to susceptibility to poliovirus infection.

Child, Preschool↗

PubMed1989

Effect of chloride on blood pressure and sympathetic nervous system activity in deoxycorticosterone acetate-treated rats.

The effect of selective chloride loading on blood pressure and sympathetic nervous system activity was studied in deoxycorticosterone acetate (DOCA)-treated rats. The rats fed a normal sodium-high chloride and fed a high sodium chloride diet had higher blood pressure and lower cardiac norepinephrine concentrations than those fed a normal sodium chloride diet. Furthermore, cardiac norepinephrine concentrations were significantly correlated with systolic blood pressure. These data suggest that selective chloride loading can raise blood pressure in DOCA-treated rats due to augmented sympathetic nervous system activity.

Animals↗

PubMed1989

Thymic atrophy characteristic in transgenic mice that harbor pX genes of human T-cell leukemia virus type I.

The human T-cell leukemia viruses (HTLV) are associated with T-cell malignancies in humans. The malignant transformation occurs after a long latency in some carriers, and its mechanism appears to be distinct from that of other classes of retroviruses which induce transformation through viral or cellular oncogenes. A widely postulated explanation is that the products of novel pX genes transactivate endogenous cellular genes which lead to tumor development in T cells. To directly examine the pathological effects of pX genes in vivo, we produced transgenic mice harboring the HTLV type I pX genes under several regulatory units: HTLV type I long terminal repeat, immunoglobulin enhancer-simian virus 40 promoter, and mouse mammary tumor virus long terminal repeat. Atrophy of the thymus was characteristic in these mice no matter which regulatory unit directed the expression of the genes.

Animals↗

PubMed1989

Effect of oral calcium on blood pressure response in salt-loaded borderline hypertensive patients.

To clarify the mechanism of the antihypertensive effect of oral calcium loading, we studied the effect of low versus high calcium intake on salt-induced blood pressure elevations in patients with borderline hypertension. After a 7-day period of dietary salt restriction (50 meq/day), 27 patients were placed on a high salt (300 meq/day), low calcium (250 mg/day) diet for 7 days; 14 of these patients were given 2,160 mg/day of supplementary calcium (Ca group), and 13 patients were given placebo (non-Ca group). With a high salt intake, the percent increase in mean blood pressure was smaller in the Ca group than in the non-Ca group (+2.85 +/- 1.22% vs. +8.63 +/- 1.66%, respectively, p less than 0.01). The Ca group showed a smaller weight gain (p less than 0.05) and a greater urinary excretion of sodium (p less than 0.005) than the non-Ca group. In the Ca group, but not in the non-Ca group, high salt intake resulted in an increase in intraerythrocyte magnesium content (p less than 0.01), which was correlated inversely with the salt-induced changes in mean blood pressure (r = -0.54, p less than 0.05). While the increase in cellular magnesium was greater in the Ca group, the changes in red blood cell sodium and sodium/potassium ratio were not different between the two groups. The results suggest that oral calcium supplementation may prevent a rise in blood pressure in patients on a high salt, low calcium diet by attenuating the sodium retention.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗

PubMed1989

[The influence of the operating positions on the prepared abutment contour of full cast crowns. Unanatomical artificial teeth for fixed bridge].

With a view to research the effect of the crown form, we made the unanatomical artificial teeth and some doctors to do the abutment tooth preparation with full cast crowns for the maxillar left fixed prosthodontics three-unit bridge in random position. After that, following are the results of a study made on the influence to the prepared tooth form. The prepared teeth are the second premolar and the second molar (The "second premolar" is abbreviated to "5" and the "second molar" is abbreviated to "7"). 1. The reductions of occlusal surface was excessively larger at 5 and 7 buccal cusp regions, while it was excessively smaller at central groove area. 2. The reductions of axial surface and subgingival area were excessively smaller at 5 and 7. 3. As for the degree of axial taper, its was steeper toward the buccal and distal surfaces at 5 and 7. 4. As for the relative degree of axial taper, it get the largest in degree on both sides between 5 medial surface and 7 distal surface. The results of this experiment are similar to the results that used anatomical artificial teeth. These results are affected by the operating posture.

Crowns↗

PubMed1989

[Study on determination of the imaginary axis of the tooth crown. 1. Measuring procedure].

The state of inclination and the change under various conditions of the imaginary axis of the tooth crown of upper jaw and lower jaw right and left first molar can be determined by the measuring apparatus and method of this study. 2. The measurement error of this method was not more than 0.1 degree. This value was sufficient for the purpose of this study.

Molar↗

PubMed1989

[Detection of human papillomavirus genome in nasolaryngeal papillomas using digoxigenin labeled DNA probes].

It is being reported that human papillomavirus (HPV) has been implicated in the pathogenesis of various neoplastic lesions of the genital organs. To investigate the etiological role of HPV and its types in nasolaryngeal papillomas, we retrospectively analyzed HPV genomes by nucleic acid hybridization methods; for detecting DNA and mRNA, we employed the recently developed nonradioactive (digoxigenin labeled) DNA probes and compared the results by radioisotope methods. In total, 43 cases of papillomatous lesions were examined. They were verruca vulgaris of the nasal vestibule (Nr = 2), nasal inverted papilloma (IP, Nr = 26), and laryngeal papilloma (Nr = 15). HPV types examined were type 2, 6, 11, 16 and 18. Two cases of verruca vulgaris were shown to contain HPV-2 DNA and its mRNA by in situ hybridization. HPV-11 DNA was detected in 3 cases (12%) of nasal inverted papilloma whereas HPV-16 was detected in 1 case (4%); the latter case was associated with squamous cell carcinoma. These results suggest that HPV may be implicated in the development of IP, and HPV-16 may play an important role in the malignant transformation of IP. In the cases of multiple laryngeal papilloma (Nr = 8, one juvenile type and 7 adult type), either HPV-6 or HPV-11 was detected at the high rate (6/8, 75%). The presence of the HPV genomes provides strong evidence for the HPV etiology of these laryngeal papillomas. Whereas in the cases of adult single laryngeal papilloma (Nr = 7), HPV was not detected. Technically, the sensitivity of digoxigenin (DIG) labeled DNA probe was almost same as 35S labeled probe by dot blot hybridization, thus we applied DIG labeled probe to Southern blot hybridization with low background. By in situ hybridization using digoxigenin labeled probes, the rates of HPV detection were almost equal to those by 35S labeled probes.(ABSTRACT TRUNCATED AT 250 WORDS)

DNA Probes, HPV↗