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H Ichikawa

Publications and source records attributed to H Ichikawa.

At least 289 records · Page 16Linked to original sources
PubMed1994

[A case of bilateral cerebellar peduncle infarction with bilateral hearing impairment of a sudden onset].

We reported a patient with bilateral cerebellar peduncle infarcts who had an abrupt onset of bilateral hearing loss. A hypertensive 56-year-old man suddenly experienced bilateral hearing loss without other accompanying neurological deficits. He was hospitalized and treated for "idiopathic deafness". In addition, dysarthria and ataxic gait appeared two days later and he was transferred to our hospital. On neurological examination, the patient presented with diplopia, neurosensory hearing loss (approximately 70 dB) ataxic dysarthria, bilateral cerebellar ataxia and bilateral Babinski's signs. Auditory brain stem evoked response demonstrated prolonged delay of interpeak latency between waves III-IV. CT and MRI revealed fresh ischemic lesions symmetrically located at the middle cerebellar peduncles and cerebellar medullary body. Cerebral angiography showed total occlusion of the left vertebral artery and a stenotic right vertebral artery at the ostium of the posterior inferior cerebellar artery. We postulated that hearing impairment in this patient resulted from transient ischemia of the bilateral auditory tract in the brain stem or the peripheral cochlear system, but the definitive cause of the transient hearing loss remains undetermined. Concomitant appearance of a symmetrical infarction at the cerebellar peduncles is rare. We suggest that a circulation defect involving a multivascular system, which resulted in "border zone infarction" occurred at these regions.

Arterial Occlusive Diseases↗
PubMed1994

[Lung cancer with pleural dissemination diagnosed by thoracofiberscopy: a case report].

Pleural dissemination was suspected in a 39-year-old woman with pulmonary adenocarcinoma. Thoracofiberscopy provided the preoperative exact diagnosis of pleural dissemination and the following prepare operative procedure. Thoracofiberscopy is effective for the diagnosis of pleural dissemination and the selection of operative methods in patients with pulmonary cancer.

Adenocarcinoma↗
PubMed1994

[The transverse submammary skin incision for median sternotomy].

Median sternotomy is the incision of choice to allow access to the anterior mediastinum, heart or both lungs. The vertical skin incision is cosmetically unsatisfactory for many female patients. The transverse submammary skin incision with dissection of a flap including the subcutaneous tissue and breasts allow exposure of the sternum for a median sternotomy. Seventy patients with the transverse submammary skin incision was compared with 56 patients with the vertical skin incision in the point of the cosmetic aspect and satisfaction of patients. The transverse submammary skin incision needed a longer wound size and took a longer time for cardiopulmonary bypass, but there were no difficulties in cannulating the ascending aorta for cardiopulmonary bypass. The exposure of the mediastinum and the cosmetic result were excellent. The complications associated with this incision are insignificant if close attention is paid to details.

Adolescent↗
PubMed1994

[Myocardial protection and the sarcoplasmic reticulum--the effect of ryanodine treatment prior to cardioplegic arrest on post-ischemic functional recovery].

Sarcoplasmic reticular (SR) calcium depletion may contribute to the myocardial protection against ischemia and reperfusion-induced injury. We have, therefore, investigated the effect of ryanodine-induced SR calcium depletion on the myocardial protection when given during Langendorff perfusion before ischemia in the isolated working rat heart. Hearts (n = 6/group) from male Wistar rats were aerobically (37 degrees C) perfused (20 min) with bicarbonate buffer (the first working perfusion), and then aerobically (37 degrees C) perfused with bicarbonate buffer containing 0, 1.75 or 7.00 nmol/L of ryanodine (a Langendorff perfusion). Hearts were then aerobically (37 degrees C) perfused (20 min) with ryanodine-free bicarbonate buffer (the second working perfusion). This was followed by a 3 min infusion of St. Thomas' Hospital cardioplegic solution, and then subjected to 38 min of normothermic (37 degrees C) global ischemia and 35 min of reperfusion (15 min Langendorff, 20 min working). After the ryanodine treatment, the percent reduction in aortic flow was significantly greater in the 7.00 nmol/L ryanodine group than in the control group. The post-ischemic recoveries of aortic flow were 39.1 +/- 3.3, 32.8 +/- 5.3 and 37.3 +/- 4.4% in the 0, 1.75 and 7.00 nmol/L ryanodine groups, respectively. There was no difference in the creatine kinase leakage during Langendorff reperfusion between the ryanodine-treated groups and the control group. Thus, ryanodine decreased the cardiac function after the ryanodine treatment, indicating a reduction in SR calcium content. Ryanodine, however, failed to improve the post-ischemic functional recoveries.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Changes in tissue antioxidant enzyme activities and lipid peroxides in endotoxin-induced multiple organ failure.

Intravenous administration of bacterial endotoxin (lipopolysaccharide: LPS) induces shock and disseminated intravascular coagulation in rats. Our report here shows that LPS-administered rats (10 mg/100 g) develop tissue injuries and functional disorders in multiple vital organs. In the present study, we investigated changes in tissue antioxidant enzyme activities, neutrophil sequestration, and lipid peroxides in multiple organs (lung, stomach, small intestine for antioxidant enzyme activities and neutrophil sequestration; lung, stomach, small intestine, liver, abdominal aorta for lipid peroxides) of LPS-treated rats. LPS-treated animals morphologically revealed pulmonary interstitial edema, alveolar hemorrhage, and mucosal hemorrhage in the small intestine 45 min after LPS administration. Blood samples withdrawn from LPS-treated animals exhibited increases in serum amylase, blood urea nitrogen, creatinine, and transaminase levels up to 180 min post-LPS infusion. LPS-treated animals showed a significant increase in tissue myeloperoxidase (MPO) activities of the lung, but not of the small intestine and stomach 45 min after LPS infusion. Thiobarbituric acid reactive substances (TBARS) in the lung, small intestine, stomach, liver, and abdominal aorta significantly increased at 45 min post-LPS-infusion. Tissue superoxide dismutase (SOD) activities of the LPS-treated animals demonstrated a significant decrease in the lung, which suffered from severe insults and neutrophil sequestration; no significant change in the small intestine, which suffered from morphological insults without neutrophil sequestration, and a significant increase in the stomach, which showed no histological impairment, at 180 min post-LPS administration. Glutathione peroxidase (GSH-PX) activities of the lung and small intestine showed no significant change in LPS-treated rats, while those of the stomach revealed a marked increase.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

[Sarcoplasmic reticular calcium release and myocardial protection--effect of ryanodine on myocardial ischemia and reperfusion-induced injury].

Calcium release from sarcoplasmic reticulum (SR) may contribute to the intracellular calcium overload observed during myocardial ischemia and reperfusion. We have therefore investigated the ability of ryanodine to enhance myocardial protection when given before ischemia or during reperfusion in the isolated working rat heart. Hearts (n = 6-9/group) from male Wistar rats were aerobically (37 degrees C) perfused (20 min) with bicarbonate buffer (Ca2+ = 2.4 mM). In the first series of studies, this was followed by a 3 min infusion of St Thomas' Hospital cardioplegic solution containing various concentrations of ryanodine. Hearts were then subjected to 38 min of normothermic (37 degrees C) global ischemia and 35 min of reperfusion (15 min Langendorff, 20 min working). The recoveries of aortic flow (%AF) were 50.3 +/- 2.5% in the ryanodine free controls versus 55.2 +/- 5.8, 72.0 +/- 1.3 (p < 0.05), 61.0 +/- 4.3, 51.8 +/- 5.1 and 32.1 +/- 5.0 (p < 0.05)% in the 0.88, 1.75, 2.13, 2.50 and 10.00 nM ryanodine groups, respectively. Creatine kinase (CK) leakage during Langendorff reperfusion was reduced in the 1.75 nM group but was similar to control in all other groups. In the second series of studies, 3 min of cardioplegia without ryanodine and 38 min of ischemia (37 degrees C) were followed by 15 min of Langendorff reperfusion with 0, 0.09, 0.18, 0.88 or 1.75 nM ryanodine, %AF was 59.3 +/- 3.3%, 54.7 +/- 3.3, 53.8 +/- 3.5, 38.4 +/- 8.9 (p < 0.05) and 33.3 +/- 5.8 (p < 0.05)% in the 0, 0.09, 0.18, 0.88 and 1.75 nM ryanodine groups, respectively. CK leakage tended to increase dose-dependently.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

[Long-term results after surgical repair for aged atrial septal defect].

Between 1980 and 1992, 84 patients over 30 years were underwent operative closure of atrial septal defect (ASD). Preoperative complaints and lower cardiac function were more frequent in the older than in the younger, but the clinical symptom of both generation improved significantly after surgery. Only a 67-year-old patient died after surgery due to low cardiac output syndrome. No long-term death occurred. The incidence of atrial fibrillation was increased postoperatively compared with preoperatively. Therefore, we recommend early surgical repair for aged ASD before thirties, if possible.

Adult↗
PubMed1994

[Surgical treatment of abdominal aortic aneurysm associated with idiopathic thrombocytopenic purpura and consumption coagulopathy: a case report].

A 68-year-old man who had abdominal aortic aneurysm (AAA) associated with idiopathic thrombocytopenic purpura (ITP) and consumption coagulopathy was successfully operated upon. The count of platelet was improved from 1.4 x 10(4)/microL to 8.0 x 10(4)/microL by the preoperative treatment with gamma-globulin (400mg/kg/day for 5 days) and heparin sodium (10000-15000 unit/day). Abdominal aortic aneurysm was replaced with a Y-shaped knitted Dacron graft, and splenectomy was performed for ITP. No severe hemorrhagic diathesis was encountered during and after the operation. This is the first report of surgical treatment of AAA associated with ITP and consumption coagulopathy.

Aged↗
PubMed1994

[Surgical repair of an extreme type of tetralogy of Fallot using valved extracardiac conduit].

Three patients with an extreme type of tetralogy of Fallot underwent corrective surgery using the valved extracardiac conduit for reconstruction of the main pulmonary arteries. The conduit consisted of bicuspid valve which was made of heterogeneous pericardium of 18 or 20 mm in diameter. The conduit was sutured to the pulmonary artery followed by an end-to-end anastomosis between the conduit and a Dacron tube which was sutured to the right ventricular outflow tract. Postoperative echocardiography showed little pulmonary regurgitation. Postoperative courses of all the patients have been uneventful.

Blood Vessel Prosthesis Implantation↗
PubMed1993

Calretinin-immunoreactivity in trigeminal neurons innervating the nasal mucosa of the rat.

Trigeminal primary neuronal cell bodies were labeled by retrograde transport of Fluoro-gold (FG) from the nasal mucosa of rats. The trigeminal ganglion containing the labeled cell bodies were processed for double stain for calretinin- and tachykinin-immunoreactivities (CR- and TK-irs). Except for a few contralateral cells, all the cells that innervated the nasal mucosa (NM cells) were confined to the ophthalmo-maxillary division of the trigeminal ganglion ipsilateral to the FG application. In the dorsal two-thirds of the ganglion, NM cells formed a cluster in the rostromedial part of ophthalmo-maxillary division (the rostromedial cluster). In the ventral third, the number of cells in the rostromedial cluster markedly decreased. Instead, numerous NM cells were found in the caudolateral part of the ophthalmo-maxillary division (the caudoventrolateral cluster). CR- and TK-irs were detected in 18% and 54% of overall population of NM cells, respectively. Virtually all of CR-immunoreactive (-ir) NM cells coexpressed TK. Although the proportion of TK-ir cells, irrespective of CR-ir, was similar for both clusters, CR-ir cells were more frequent in the caudoventrolateral cluster than in the rostromedial cluster. In the dorsal 1/3 of the ganglion where all the NM cells belonged to the rostromedial cluster, only 8.4% exhibited CR-ir. On the other hand, as much as 30.1% of NM cells expressed CR-ir in the ventral 1/3 where most NM cells were found in the caudoventrolateral cluster. Trigeminal cell bodies innervating the cornea and conjunctivum were located in the rostromedial part of the ophthalmo-maxillary division.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

An ets-related gene, ERG, is rearranged in human myeloid leukemia with t(16;21) chromosomal translocation.

The t(16;21)(p11;q22) translocation is a nonrandom chromosomal abnormality found in several types of myeloid leukemia, which show variable cytomorphological features. We constructed rodent-human somatic cell hybrids containing the der(16) chromosome from leukemic cells of a patient with t(16;21). Using these hybrids, we mapped the translocation breakpoint on the Not I restriction map of chromosome 21 which we had previously constructed. The result showed the proximity of the breakpoint to the ERG gene, a member of the ets oncogene superfamily. Polymerase chain reaction and Southern blot analyses of genomic DNA from the hybrids and from peripheral blood cells and bone marrow cells of patients with t(16;21) showed that the breakpoints were clustered within a single intron in the coding region of the ERG gene. This finding and the results obtained by Northern blot analysis suggested the formation of a chimeric product(s) by fusion of the ERG gene and an unknown counterpart gene on chromosome 16.

Acute Disease↗
PubMed1993

c-Fos expression by dorsal horn neurons chronically deafferented by peripheral nerve section in response to spared, somatotopically inappropriate nociceptive primary input.

Subcutaneous formalin injection into the hindpaw of rats induces c-Fos expression in neurons in the ipsilateral spinal cord dorsal horn. In laminae I and II of the dorsal horn at the junction of 4th and 5th segments of the lumbar spinal cord, neurons exhibiting c-Fos protein-like immunoreactivity (Fos-LI) are concentrated in the medial 3/4 that correspond to the terminal field of primary neurons innervating the sciatic nerve. Subacute tibial nerve section 24 h before formalin stimulation caused almost complete elimination of neurons with the formalin-induced Fos-LI in the medial 1/2 (tibial territory) of the above sciatic territory of the dorsal horn. Following a longer survival period (chronic tibial nerve section of 21 days standing), neurons with the formalin-induced Fos-LI re-appeared in the tibial territory. In addition, the number of neurons with the formalin-induced Fos-LI increased in the medial part of the peroneal territory (the lateral 1/2 of the sciatic territory). The results indicate that the activation of c-Fos expression in that part of dorsal horn that has been chronically deafferented by the tibial nerve section is taken over by the spared, but somatotopically inappropriate primary nociceptors. Furthermore, dorsal horn neurons outside but near the deafferented tibial nerve's territory exhibit hypersensitivity to c-Fos expression evoked by intact, somatotopically appropriate primary nociceptive input.

Animals↗
PubMed1993

Expression of intercellular adhesion molecule-1 on cardiac myocytes for myocarditis before and during immunosuppressive therapy.

Right ventricular endomyocardial biopsies were performed in 15 patients with unexplained cardiac dysfunction, and the expression of intercellular adhesion molecule-1 (ICAM-1) on the myocardium was examined using the streptavidin-biotin complex method. Three of 15 patients (20%) had histologic evidence of myocarditis, and 2 of 15 patients (13%) had borderline myocarditis. The patients with biopsy-proven myocarditis received immunosuppressive therapy (prednisolone 60 mg/day). Two of the 3 patients demonstrated a substantial increase (> 10%) in percent fractional shortening and left ventricular ejection fraction during therapy. Subsequent biopsies revealed ongoing myocarditis in 1 patient, and resolved myocarditis in the other. The remaining patient had persistent cardiac dysfunction, but the subsequent biopsy revealed resolving myocarditis. ICAM-1 immunoreactivity was observed on cardiac myocytes, vascular endothelial cells, and interstitial cells of the patients with myocarditis. However, in patients without myocarditis, ICAM-1 immunoreactivity was observed only on vascular endothelial cells and interstitial cells. ICAM-1 immunoreactivity was still observed on cardiac myocytes in the patients with ongoing or resolving myocarditis during immunosuppressive therapy, but was not detected in the patient with resolved myocarditis. This study demonstrates that ICAM-1 is expressed on cardiac myocytes of patients with myocarditis and persistent cardiac dysfunction despite immunosuppressive therapy. The persistent expression of ICAM-1 may cause chronic inflammation of the myocardium.

Adult↗
PubMed1993

Response of neurons in the solitary tract nucleus, area postrema and lateral parabrachial nucleus to gastric load of hypertonic saline.

c-Fos was induced in the solitary tract nucleus (NTS), area postrema (AP) and lateral parabrachial nucleus (LPB) by the intragastric injection of hypertonic saline. The effect was bilateral and most dramatic in the NTS caudal to the facial nucleus and the AP, the areas receiving dense vagal afferent projection from the subdiaphragmatic structures. At least a part of these Fos-LI is considered to have been induced by the activation of the visceral osmoreceptors.

Animals↗
PubMed1993

Calretinin-immunoreactive neurons in the trigeminal and dorsal root ganglia of the rat.

The cell body size of primary neurons were measured in the trigeminal (TG) and lumbar dorsal root ganglia (DRG) monochrome-stained for calretinin (CR)-like immunoreactivity. A trichrome stain for CR, carbonic anhydrase (CA) and tachykinin (TK) was also employed to estimate possible overlap of cellular distribution of these substances. In the DRG, the cell size spectrum of CR-positive cells was clearly bimodal; a greater proportion (84.1%) of CR-positive cells was distributed in the range > or = 800 microns2 with a mode between 1,500-1,600 microns2, while a smaller proportion (14.8%) < 700 microns2 with a mode of 400-500 microns2. They were evenly distributed throughout the DRG. Although CR-positive TG neurons were smaller than similar DRG neurons, a bimodal distribution pattern remained unchanged. 94.6% of CR-positive cells measured 100-1,400 microns2 with peak ranges of 200-300 microns2 and 400-500 microns2. Most of CR-positive cells in the ophthalmic division were 400 microns2 or larger and small CR-positive cells (< 400 microns2) were concentrated in the maxillary and mandibular divisions. Most of CR-positive DRG cells showed CA activity (76.5%), while those with TK-immunoreactivity were rare (7.2%). In the TG, 38.4% of CR-positive cells were TK-positive. They were mostly smaller than 800 microns2. On the other hand, CA was detected in 43.4% of CR-positive TG cells. Most of the TG cells co-expressing CR and CA were 400 microns2 or larger. Simultaneous co-expression of TK and CA by the CR-positive cells was negligible.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Presence and coexistence of putative neurotransmitters in carotid sinus baro- and chemoreceptor afferent neurons.

The presence and coexistence of tyrosine hydroxylase (TH), vasoactive intestinal polypeptide (VIP), calcitonin gene-related peptide (CGRP), substance P (SP) and galanin (GAL) were studied in the petrosal and jugular neurons innervating the carotid body and carotid sinus of the rat. The retrograde labeling of the carotid sinus nerve with Fluoro-gold (FG) demonstrated that most (94.5%) FG-labeled ganglionic neurons were observed in the petrosal ganglion. Fewer (5.2%) FG-labeled neurons were seen in the jugular ganglion and very few (0.3%) were observed in the nodose ganglion. Immunohistochemistry revealed that subpopulations of TH-, VIP-, CGRP-, SP- and GAL-immunoreactive (-ir) neurons in the petrosal ganglion projected to the carotid sinus nerve. Approximately 4% of FG-labeled neurons contained TH-ir and were predominantly found in the caudal portion of the petrosal ganglion. Nearly 90% of total TH-ir neurons in the petrosal ganglion were labeled with FG. Less than 1% of FG-labeled neurons were immunoreactive for VIP in this ganglion. In the petrosal ganglion, 25% of FG-labeled neurons contained CGRP-ir, and 16.7% of FG-labeled neurons contained SP-ir. 30% of CGRP-ir or SP-ir neurons in the petrosal ganglion were labeled with FG. In the jugular ganglion, no TH- or VIP-ir neurons projected to the carotid sinus nerve and only small populations of CGRP- or SP-ir neurons projected to the carotid sinus nerve. Many FG-labeled and GAL-ir neurons were observed in the petrosal and jugular ganglia.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Changes of lectin staining pattern of the Golgi stack during differentiation of the ameloblast in developing rat molar tooth germs.

Changes of lectin staining patterns in the Golgi stack during cell differentiation were examined in the ameloblasts of developing rat molar tooth germs, using HRP-labeled lectins: Canavalia ensiformis (Con A), Griffonia simplicifolia I (GS-I), Glycine max (SBA), Ulex europeus I (UEA-I), Triticum vulgaris (WGA), and Arachis hypogaea (PNA). The Golgi stacks of the inner enamel epithelial cells and the presecretory ameloblasts were stained with the lectins, although the staining strength and pattern varied among the stacks with each lectin. In some cases, the reaction products for the lectins were observed in most or all saccules of the Golgi stack. In the secretory ameloblasts, however, discrete staining patterns of the Golgi stack were found for each lectin. The reaction products deposited in definite saccules of the Golgi stack of the secretory ameloblast, especially for UEA-I and PNA which stained only the trans Golgi saccules of the stack. The reaction-positive saccules distributed more extensively in the Golgi stack of the inner enamel epithelial cell and the presecretory ameloblast than in the secretory ameloblast. These findings suggest that the Golgi stack is not fully compartmentalized in the inner enamel epithelial cell and the presecretory ameloblast. It is proposed that, in the differentiating ameloblast, various glycosyltransferases may coexist in most saccules of the Golgi stack.

Ameloblasts↗