Biomedical subjects

H Kurihara

Publications and source records attributed to H Kurihara.

422 records · Page 24Linked to original sources

PubMedDate not supplied

[Surgical treatment of ulcerative rectocolitis: technical aspects of total restorative proctocolitis with S pouch].

Restorative proctocolectomy with an ileal-pouch-anal anastomosis seems to be the treatment of choice for ulcerative colitis. The aim of this study was to discuss a number of technical and functional aspects of the procedure that still appear to be controversial such as the shape of the pouch, the mucosectomy and the type of anastomosis. The authors report on their experience with the surgical treatment of ulcerative colitis with an "S" pouch. The technique reported, however, differs from the original method proposed by Parks and Nicholls in 1978 and the reasons for this surgical choice are discussed. A six-year experience (1993-1999) regarding 35 patients undergoing this approach is reported. No perioperative deaths were observed. The early and long-term complication rates were 8.5% and 11.4%, respectively. The average number of daily evacuations was 4. Mucosectomy affords complete resolution of the disease, while the particular shape of the pouch guarantees good functional results.

Adolescent↗

PubMedDate not supplied

Dysplastic glioneuronal lesion arising in the cerebellum: a clinicopathological, immunohistochemical and ultrastructural study.

We describe a case of dysplastic glioneuronal lesion in the right cerebellar hemisphere. A 13-year-old boy presented with headache since 1998. He had no neurological deficits. The computerized tomograph (CT) scan showed prominent calcification, and magnetic resonance imaging (MRI) revealed a non-enhancing mass of 15 x 15 x 5 cm in the right cerebellar hemisphere. The mass had low intensity in T1- and high intensity in T2-weighted images. Histologically, the lesion was composed of poorly defined small to intermediate sized cells arranged in fibrillar background. Although few neuronal cells having large nuclei with small nucleoli were present, no ganglion cells could be seen. Immunohistochemically, these poorly defined cells were non-reactive to various glial and neuronal markers. However, GFAP, synaptophysin, neurofilament and vimentin-reactive intercellular matrix and few nonneoplastic GFAP-positive glial cells and neurofilament-positive neuronal cells were seen. A very low MIB-1-labelling index of less than 0.1% was noted. Ultrastructurally, two different populations of the cells were seen. A few neuronal cells were larger and had an oval nucleus with small nucleolus and cytoplasm containing various cytoplasmic organelles, Golgi apparatus, mitochondria, ribosomes, lipofuscin, rough endoplasmic reticulum, microtubules and neurofilaments. Many other cells had a scant cytoplasm and thus poorly defined. Cytoplasmic processes with axono-dendritic synapses and foci of bundles of intermediate filaments were present in the intercellular areas of the lesion. Based on these radiological, histological and ultrastructural findings of the lesion of low proliferative potential, we considered it dysplastic in nature.

Adolescent↗

PubMedDate not supplied

Glioblastoma with large numbers of eosinophilic hyaline droplets in neoplastic astrocytes.

We report a case of glioblastoma with unusual histological features arising in the left frontal lobe of a 79-year-old woman. On routine histological examinations of specimens obtained at the surgical resection, the tumor was consistent with glioblastoma, and intracytoplasmic inclusions of bright eosinophilic, round objects were found in a large number of neoplastic astrocytes. Pathological studies using histochemical/ immunohistochemical stainings and electron microscopy demonstrated that the inclusions were compatible with eosinophilic hyaline droplets (EHD), which are predominantly seen in pleomorphic xanthoastrocytoma and pilocytic astrocytoma. EHD-bearing cells were distributed throughout the tumor tissue and focally abundant (182/mm2). Most of those cells were negative for MIB- I immunostaining, although mitotic figures were rarely observed. Neither round granular body nor Rosenthal fibers were seen. Based on these neuropathological findings and a review of the literature, we concluded that this case was a very rare case of glioblastoma with numerous EHDs. The presence of numerous EHDs is considered a diagnostically helpful feature suggesting low-grade astrocytomas. The present case suggested that diagnostic application of numerous EHDs should be careful, particularly in small biopsy samples such as stereotactic biopsy.

Aged↗

PubMedDate not supplied

Preneoplastic transformation in mouse mammary tissue: identification and validation of intermediate biomarkers for chemoprevention.

Specific and sensitive markers capable of determining the extent of tumorigenesis are important end points not only for evaluating the carcinogenic potency, but also for assessment of chemopreventive efficacy of modulators. Prototypic mammary carcinogens induce a high frequency of mammary adenocarcinomas. The appearance of tumors, however, is a culmination of initiational and promotional events whose modulation may constitute an effective means for chemopreventive interventions. The purpose of this study was i) to identify intermediate biomarkers for mammary cell transformation and ii) to apply these biomarkers and validate the ability of selected fatty acids to modulate chemical carcinogen-induced tumorigenic transformation. An in vitro model derived from mouse mammary explant cultures was utilized to examine the effects of 7,12 dimethylbenz (a) anthracene (DMBA), a prototype chemical carcinogen for rodent mammary gland. The effects of DMBA exposure were quantified at the molecular level by determining induction of oncogene expression, at metabolic level by determining the extent of estradiol metabolism, and at cellular level by determining the emergence of hormone-independent mammary alveolar lesions (MAL) and their tumorigenic potential. DMBA treatment induced binding of ras oncogene product ras p21 to [alpha 32P] GTP, altered estradiol metabolism by increasing the ratio of C16 alpha/C2 hydroxylation in favor of 16 alpha-OHE1 formation, and exhibited high frequency of MAL. Transplantation of cells from these MAL produced rapidly growing tumors. Treatment of DMBA-exposed cultures with polyunsaturated n-6 fatty acids enhanced, and treatment with polyunsaturated n-3 fatty acid suppressed the molecular, metabolic and cellular intermediate biomarkers for tumorigenic transformation. Thus, oncogene expression, estradiol metabolism and formation of MAL may constitute useful molecular, metabolic and cellular intermediate biomarkers. Alteration of these biomarkers by selected fatty acids is suggestive of their utility as end points for the chemopreventive efficacy of dietary agents.

9,10-Dimethyl-1,2-benzanthracene↗

PubMedDate not supplied

Modulation in the expression of murine mammary tumor virus, ras proto-oncogene, and of alveolar hyperplasia by fatty acids in mouse mammary explant cultures.

Hyperplastic alveolar nodule, present in the young adult non-lactating but mammary tumor virus harbouring mice (RIII), are biologically active precursor lesions which form mammary tumors at certain age. Using mammary explant cultures from these mice as a model for preneoplastic hyperplasia, we have examined the effects of various fatty acids on the changes in the cellular and molecular markers in vitro. We find that exposure of cultures to omega-6 fatty acids results in -13 fold increase on RT activity, -3 fold increase in expression of c-ras Hp21, and 2 fold increase in the frequency of lactogenic hormone-independent mammary alveolar lesions, MAL. In contrast, exposure of the cultures to eicosapentanoic or stearic acid results in no increase in RT activity, 3-fold decrease in expression of C-ras Hp21, and about 2-fold decrease in MAL frequency. These results suggest that tumor modulating effects of dietary fatty acids may be operative during the initiational and promotional events of viral carcinogenesis, well before the emergence of mammary tumors.

Animals↗

PubMedDate not supplied

Improvement of colo-rectal cancer surgery following introduction of endoscopical approach.

In the period 1968-1993, we treated 399 patients for colo-rectal cancer. Up to 1980, preceding large scale use of endoscopy, 217 patients, out of the group of 399, were submitted to surgery; at time of diagnosis all patients had symptoms of advanced colonic tumor (intestinal obstruction; palpable mass; significant rectal bleeding); none of the lesions detected was in Dukes A or B1 groups; 56 patients were in Dukes B2 and stages C1 + C2 + D were detected in 161 cases. In period 1981-1993 we treated 182 patients; in all cases the diagnosis consisted of endoscopical examinations. Out of this group 69 patients underwent endoscopic resection of polyps with focal neoplastic degeneration: 44 did not require surgery according to Haggitt criteria. In the group of 138 patients who underwent surgery, 89 were in Dukes A + B1 + B2 groups and 49 were in Dukes C1 + C2 + D groups. In our experience endoscopy is not essential in the clear cut colonic neoplasms, however it is an invaluable screening test in early stages, in poor symptomatic population, in elderly patients (> 50 y.o.) and in patients with non specific symptoms. We wish to emphasize how endoscopy has improved the results of colonic cancer surgery.

Colonic Polyps↗

PubMedDate not supplied

[Total gastrectomy for gastric neoplasms].

In spite of the decreasing incidence of gastric carcinoma, as it is reported in recent reports from the U.S.A., total gastrectomy and its surgical indications results and complications, focus the interest of surgeons. We analize 61 cases of total gastrectomy for carcinoma, treated in the years 1982-1992. Perioperative mortality and long term survival appear highly satisfactory, mainly if one considers that the site and extension of the neoplasms treated would have severely impaired the possibilities of cure or long term survival with surgery of lesser momentum. We believe that nowaday indications for total gastrectomy can be widened in the hope of improving results of gastric cancer surgery with no or little additional risk.

Adult↗

PubMedDate not supplied

Effect of transaortic catheter venting on left ventricular function during venoarterial bypass.

Although venoarterial bypass (VAB) or percutaneous cardiopulmonary support (PCPS) can improve hemodynamics in patients with serious cardiac decompression, some cannot be weaned from circulatory support. Insufficient unloading of the left ventricle (LV) with blood stagnation is a main cause of unsuccessful LV recovery during PCPS. This investigation was undertaken to evaluate the effectiveness of transaortic catheter venting (TACV) for LV unloading. Eight mongrel dogs (mean weight 16.3 kg, range 14-20 kg) underwent VAB with TACV. In addition to monitoring standard hemodynamic parameters, the slope of the LV end systolic pressure-volume relationship (Emax) during transient occlusion of the inferior vena cava, the slope of LV end systolic pressure-stroke-volume (Ea), external stroke work (SW), LV pressure-volume area (PVA), and slope of the SW-end diastolic volume relationship (preload recruitable stroke work: PRSW) were assessed by means of a micro-tip manometer and a conductance catheter. We measured data under the following four conditions; before circulatory support (baseline), during isolated VAB, VAB with TACV, and VAB with TACV plus intra-aortic balloon pumping (IABP). The LV contractility (Emax) and LV elastance (Ea) were equivalent for the four conditions. By comparison with baseline and VAB with TACV, LV energy (PVA) and work (SW, PRSW) were significantly reduced by TACV (1283.9 +/- 197.1 vs. 793.3 +/- 124.8 x 10(-4) J, 897.1 +/- 147.2 vs. 474.2 +/- 83.0 x 10(-4) J and 35.6 +/- 2.7 vs. 25.7 +/- 1.7 x 10(-4) J/ml, respectively), and the PE/PVA increased with TACV (30.4 +/- 2.6 vs. 40.8 +/- 1.8%). In contrast, there was no significant difference in PVA, SW, PRSW, and PE/PVA between baseline and isolated VAB. These results suggest that TACV might be an adjunctive technique to VAB or PCPS for patients with LV failure.

Animals↗