Search PubMed⌕ Search

Biomedical subjects

T Kawashima

Publications and source records attributed to T Kawashima.

At least 127 records · Page 7Linked to original sources
PubMed1995

Differential vocalization in budgerigars: towards an experimental analysis of naming.

In Experiment 1, 3 budgerigars (Melopsittacus undulatus) were trained with food reinforcement to make low- or high-frequency calls in response to different color stimuli, C1 and C2 (a color-naming task), using a gradual response-differentiation procedure and an automatic call-recognition system. Thus, a call within a certain frequency band was reinforced in the presence of C1 ("C1 call"), and a call within a different band was reinforced in the presence of C2 ("C2 call"). In Experiment 2, all 3 budgerigars were trained in a form-to-color matching-to-sample task, alternating trial by trial with either the color-naming task (2 birds) or an identity color matching-to-sample task (1 bird). Sample stimuli for the new matching-to-sample task were forms (F1 or F2) and comparisons were the same two colors (C1 and C2). Given Sample F1 or F2, birds had to make a call to produce Comparison Pair C1 and C2. With F1 as the sample, a peck on C1 was reinforced; with F2 as the sample, a peck on C2 was reinforced. Although no particular call was specified in the presence of F1 and F2, 2 birds made the C1 call in the presence of F1 and the C2 call in the presence of F2. In Experiment 3, the bird that failed to match form and color calls in Experiment 2 and another bird were first trained in a color-to-form matching-to-sample task: C1 to F3 and C2 to F4. In this task, to produce the comparison pair of forms, a high call (or low for the other bird) was required in the presence of C1, and a low call (or high) was required in the presence of C2. Both birds were then trained with an identity matching-to-sample task in which sample and comparison stimuli were the same two forms, F3 and F4. Trials on the identity task alternated with the color-to-form trials. Although no particular call was required in the presence of Samples F3 and F4, both birds came to make the C1 call in the presence of F3 and the C2 call in the presence of F4. Our technique promises to be useful for the study of emergent vocal relations in budgerigars and other animals.

Animals↗
PubMed1995

[Rupture of dissecting aortic aneurysm associated with the right-sided aortic arch and anomalous course of the left brachiocephalic vein--a case report].

A case of ruptured dissecting aortic aneurysm (DeBakey IIIb) associated with the right sided aortic arch and anomalous course of the left branchiocephalic vein was reported. A sixty-nine-year-old female suddenly had the severe back pain and soon fell into shock. The diagnosis of a ruptured dissecting aortic aneurysm associated with the right sided aortic was obtained on CT scanning. CT films also showed the left brachiocephalic vein behind the ascending aorta. Emergency operation was performed through median sternotomy and left thoracotomy. The descending aorta, forming an aneurysm with the aberrant subclavian artery, prominently protruded far to the left, and was located behind the trachea and the esophagus. Extra-anatomical bypass grafting was performed between the ascending aorta and the distal descending aorta. The patient eventually died of multiple organ failure on the 11th day after operation. These findings were confirmed by autopsy. A rare vascular anomaly with aortic dissection was reported, and a surgical approach to that lesion was discussed.

Aged↗
PubMed1995

[HPV infection of the uterine cervix by cytodiagnosis, histodiagnosis and dot blot hybridization method].

Human papilloma virus (HPV) infection is diagnosed by morphological methods (including cytodiagnosis, histodiagnosis and electron microscopy) and DNA diagnostic methods. One of the DNA diagnostic methods, Dot blot hybridization (DBH), is generally regarded to be superior to the morphological methods in terms of specificity and sensitivity. There have recently been reports showing that such morphological methods as cytodiagnosis [for koilocytotic atypia (KC) or koilocytosis] and histodiagnosis are best for HPV detection in laboratories because they have better sensitivity, and are cheaper, and procedurally simpler than the DBH method. We compared detection rates by morphological methods (cytodiagnosis and histodiagnosis) and the DBH method. (Materials and Methods) The subjects were 377 patients who came to the Department of Obstetrics and Gynecology of Juntendo University Urayasu Hospital and had abnormal findings in the uterine cervix by cytodiagnosis of colposcopy. Uterine cervix swabs were scraped during colposcopic examination, and specimens for Papanicolaou and Giemsa staining were prepared on 2 slides. Scraping was again performed for the DBH (Vira pap. and type, Toray Industries, Inc.) method using swabs specified for the kit, and cells were obtained in a collection kit. At the same time, at least 3 sites including, possible atypical conversion zones, were biopsied, followed by paraffin embedding and hematoxylin-eosin staining of the specimens. (Results) 1) Comparison of detection rates by cytodiagnosis and the DBH method The positive rates by the DBH method were determined according to cytodiagnostic category in 377 patients. HPV-DNA was detected in every category and in 86 (22.8%) of all of the patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

[Hiatal hernia incarceration during cardiopulmonary bypass in patient with acute aortic dissection--a case report].

A 67-year-old woman was admitted to our hospital under diagnosis of Stanford type A acute aortic dissection. Chest CT showed aortic dissection from the ascending to descending aorta, and large hiatal hernia. Operation was undergone under cardiopulmonary bypass and circulatory arrest with retrograde cerebral perfusion. A graft replacement was carried out from the ascending to transverse arch aorta. After the release of the cross-clamping of aorta, the heart was gradually oppressed anteriorly by extrapericardial mass, so that the patient could not be weaned from the cardiopulmonary bypass. The mass was revealed incarcerated hiatal hernia by ultrasonography. After laparotomy, diaphragm and hiatus were incised, the incarceration was relieved and the diaphgragm was repaired with a Goretex sheet. Then the patient could be weaned from cardiopulmonary bypass. Her postoperative course was uneventful except for acute renal failure, and she was discharged 60 days after the operation. The incarceration of hiatal hernia was thought to be caused by tissue edema and small bleeding during cardiopulmonary bypass. This is the first reported case with the incarceration of hiatal hernia which occurred during cardiopulmonary bypass.

Acute Disease↗
PubMed1995

[Clonorchiasis].

Explore the source record for details and available documents.

Animals↗
PubMed1994

Alzheimer amyloid protein precursor enhances proliferation of neural stem cells from fetal rat brain.

We have investigated the effect of the Alzheimer amyloid protein precursor (APP) on the proliferation of neural stem cells. Two secretory forms of APP (sAPP770 and sAPP695, with and without the Kunitz-type serine protease inhibitor domain, respectively) were purified from conditioned media of COS-7 cells transfected with genetically modified APP cDNAs. Both secretory APPs promoted the growth of neural stem cells, and the effect of sAPP770 was greater than that of sAPP695. sAPP770 and known growth factors in combination exerted a cooperative stimulation of the stem cell proliferation. These results suggest that APP, especially APP possessing the protease inhibitor domain, regulates the growth of neuronal precursor cells during development of the nervous system.

Alzheimer Disease↗
PubMed1994

Nerve growth factor and epidermal growth factor rescue PC12 cells from programmed cell death induced by etoposide: distinct modes of protection against cell death by growth factors and a protein-synthesis inhibitor.

A rat pheochromocytoma cell line (PC12 cells) died within 24 h in the presence of etoposide (1-40 micrograms/ml), an inhibitor of topoisomerase II. This cytotoxic effect was prevented by either nerve growth (NGF) or epidermal growth factor (EGF). Cycloheximide and actinomycin D also suppressed the cell death as well. Furthermore, a difference among protective modes against etoposide-induced death by growth factors and a protein-synthesis inhibitor was observed: the protective effect of either NGF or EGF remained rather constant as a function of incubation time with etoposide whereas that of cycloheximide declined. These results indicate that etoposide induces programmed death in PC12 cells and that prevention of the programmed cell death by both NGF and EGF is mainly due to inactivation of molecules involved in the death processes rather than suppression of specific protein and/or mRNA synthesis.

Animals↗
PubMed1994

Direct interaction of proteoglycan macrophage colony-stimulating factor and basic fibroblast growth factor.

The proteoglycan form of macrophage colony-stimulating factor (PG-M-CSF), but not M-CSF with a molecular weight of 85 kD (85-kD M-CSF), bound to immobilized basic fibroblast growth factor (bFGF), and, conversely, bFGF bound to immobilized PG-M-CSF, but not to the 85-kD M-CSF. PG-M-CSF has an additional amino acid sequence at its carboxyl terminus (part of a precursor sequence that is removed in 85-kD M-CSF by proteolytic processing) and it has one or two chondroitin sulfate glycosaminoglycan chains at the carboxyl terminus. Enzymatic removal of the chondroitin sulfate chain from PG-M-CSF had no effect on the binding between PG-M-CSF and bFGF. Ligand blotting analysis with radioiodinated bFGF showed that bFGF specifically bound to the polypeptide that corresponded to the carboxyl terminus of PG-M-CSF and was produced in Escherichia coli transfected with its gene. The exogeneous addition of heparan sulfate, which has strong affinity for bFGF, efficiently inhibited the binding between PG-M-CSF and bFGF. These results show that PG-M-CSF binds bFGF through its carboxyl terminal peptide and that the binding sites for PG-M-CSF and heparan sulfate on bFGF are located close together. PG-M-CSF also significantly reduced the mitogenic action of bFGF on Balb/c 3T3 mouse fibroblastic cells. Therefore, we conclude that PG-M-CSF not only binds bFGF, but also neutralizes the activity of the growth factor.

3T3 Cells↗
PubMed1994

Etoposide induces programmed death in neurons cultured from the fetal rat central nervous system.

The effects of etoposide on the death of neurons cultured from the central nervous system (CNS) of fetal rats were examined. The cultured neurons died in the presence of 1-40 micrograms/ml of etoposide, which is known to induce programmed death in some kinds of cells, and this cytotoxic effect was prevented by inhibition of protein synthesis and/or RNA synthesis. Furthermore, DNA degradation, including a ladder-like pattern, became evident in these neurons 3 h after incubation with etoposide (10 micrograms/ml), whereas cell death commenced after about 6 h. These results indicate that etoposide-treated CNS neurons require new protein and RNA synthesis to undergo an active death programme, and that internucleosomal fragmentation of DNA mediates the etoposide-induced programmed cell death. This culture system of etoposide-treated CNS neurons is thought to be a useful model for the study of programmed neuronal cell death.

Animals↗
PubMed1994

Bone mineral density and bone histomorphometric assessments of postpregnancy osteoporosis: a report of five patients.

Reports of five young women who developed vertebral fractures associated with pregnancy and lactation are presented (Fig. 1). Ages ranged from 24 to 37 (mean 30) years. All five patients have osteoporosis with two to nine vertebral fractures at presentation postpartum. Bone mineral density (BMD) was measured by single-photon absorptiometry, quantitative computer tomography, and dual-energy X-ray absorptiometry. BMD of the trabecular bone was less than normal values and it remained apparently low even several years after pregnancy. Histological findings of bone biopsy identified the bone loss with increasing bone resorption. Our present findings suggest that postpregnancy osteoporosis affects mainly the trabecular bone site, and the patients might have low peak bone mass and poor reversibility probably due to a low rate of remodeling.

Absorptiometry, Photon↗
PubMed1994

Topography of commissural fibers in the corpus callosum of the cat: a study using WGA-HRP method.

The topography of the commissural fibers in the corpus callosum (CC) of the cat was systematically investigated using the WGA-HRP method. WGA-HRP was injected into various parts of the cerebral cortex and locations of WGA-HRP-stained commissural fibers in the CC were examined. Commissural fibers were arranged in a topological fashion in the CC. Cortical areas rostral to the cruciate sulcus (CrS), corresponding to motor or premotor cortices, projected fibers into the genu of the CC, while fibers from the cortex caudal to the CrS passed through the CC slightly caudal to the genu. When WGA-HRP was injected into the lateral gyrus (LG), it was observed that fibers from the anterior LG passed through the anterior one-third of the CC, whereas those from the posterior LG passed through or near the splenium, and fibers from the middle LG passed between those from the anterior and posterior LG. Similarly, the suprasylvian gyrus (SSG) projected commissural fibers in the CC in a rostrocaudal topological manner. Fibers from the anterior SSG passed through the anterior one-third of the CC, and those from the middle SSG through the middle one-third of the CC and upper part of the splenium. Injection into the most posterior part of the middle SSG revealed fibers passing through the caudal end of the splenium. Callosal fibers from the anterior SSG were focused on in this study, because this area (area 2v) is considered one of the vestibular projection cortices and is an area of special interest to the authors. Callosal fibers from the anterior SSG were observed to pass through the anterior one-third of the body of the CC. When WGA-HRP was injected into auditory areas, fibers from the anterior and middle ectosylvian gyri (ESG) were observed to pass through the posterior one-third of the body of the CC or through the splenium, while fibers from the posterior ESG passed through the splenium. WGA-HRP was also injected into the cingulate gyrus (CiG). Fibers from the anterior CiG (area 24) passed through the anterior portion of the CC while those from the posterior CiG (area 23) passed through the posterior portion of the CC.

Animals↗
PubMed1994

Treatment of brachymetatarsia by callus distraction (callotasis).

Callus distraction (callotasis) has already become a popular procedure in the lengthening of limbs. With the development of a small device, it can also be applied to the hand or foot, thus providing benefits in the treatment of brachymetatarsia. Four toes of 3 patients with brachymetatarsia of the fourth toe were treated by this method, and excellent elongation of from 17.50 to 32.55 mm (average, 23.71 mm) was acquired. The treatment period ranged from 78 to 141 days (average, 112.5 days). More time was required in the earlier cases, but the most recent took only 11 weeks. The optimal distraction rate is considered to be 0.35 mm per half-day. Reshortening after treatment ranged from 3.6 to 5.5 mm (average, 4.7 mm), or from 15% to 26% (average, 20.5%) of the distracted length. About 90% of the resorption was observed within 1 month, except in a case that involved a postoperative fracture, and no resorption was seen after 2 surgical months. Regarding complications, subluxation of joints was seen in 2 patients and a postoperative fracture in 1 patient. Subluxation was caused by tendons resisting elongation. The procedure is described, representative cases are illustrated, and problems encountered are discussed.

Adolescent↗
PubMed1994

Tissue expansion in facial reconstruction.

The tissue expansion technique is advantageous in facial reconstruction because it makes it possible to resurface even wider defects with neighboring skin similar in color and texture and superior to skin obtained elsewhere, thereby surpassing conventional methods. However, there still remain some problems relating to procedural details, such as the selection of tissue expanders and sites of their insertion; the design, elevation, suturing, and fixation of the expanded flap; and the management of free margins such as the lower lip and lower eyelid. In each case, some modification is required with respect to the status of the defect. The experiences encountered in a series of 23 patients are described, with illustration of several representative cases, and advantages and problems are discussed.

Adolescent↗