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Biomedical subjects

A Hirano

Publications and source records attributed to A Hirano.

At least 181 records · Page 10Linked to original sources
PubMed1995

[Two cases of isolated ambient cistern hematoma after head injury].

This is a report of two cases of isolated ambient cistern hematoma after head injury. Isolated small hematomas in the ambient cistern after head injury are considered indirect evidence of brain stem injury. In such cases the initial neurological signs are often severe, but the ultimate prognosis is almost always good or excellent. Our patients showed hardly any neurological signs, and their head trauma was not very severe. Isolated ambient hematomas are the result of injury to small vessels or of mild contusions of the brain stem produced by the edge of the tentorium. In case 2, MRI revealed small, high signal intensity near the hematoma, and this sign was interpreted as evidence of mild brain stem injury. We think our patients had very mild brain injuries which were unaccompanied by diffuse axonal injury.

Brain Stem↗
PubMed1995

[Clinical study on antimicrobial prophylaxis following extracorporeal shock wave lithotripsy].

One hundred and sixty one patients with upper urinary stones were examined for antimicrobial prophylaxis following extracorporeal shock wave lithotripsy (ESWL). They were divided into two groups, the low-risk group (n = 133) and high-risk group (n = 28), according to the risk factors of urinary tract infection. The patients in the low-risk group were further randomized into two groups which were orally given ofloxacin for 7 days after ESWL (Group A, n = 66), no antimicrobial (Group B, n = 67). The patients in the high-risk group were randomly subdivided into three groups which were given flomoxef intravenously for 2 or 3 days and ofloxacin for 4 or 5 days thereafter (Group C, n = 10), flomoxef only for 2 or 3 days and no drugs later (Group D, n = 10), ofloxacin for 7 days (Group E, n = 8). In all of the patients in the low-risk group, during the 7 days after ESWL, fever elevation was observed in only 1.5% of patients, and bacteriuria in 10.0% on the 7th day. There was no difference in frequency of fever elevation and bacteriuria following ESWL between Group A and Group B. These findings indicate that prophylactic antimicrobial after ESWL treatment is not necessary for low risk patients with urinary tract infections. In the high-risk group, the over-all rates of fever elevation and bacteriuria were 21.4% and 24.0% respectively. The difference of effectiveness among the prophylactic regimens of the three groups (Group C, D, E) was not shown.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

[Problems of postoperative care in urinary diversion: ureterocutaneostomy].

One hundred and nine patients underwent tubeless ureterocutaneostomy as a method of urinary diversion at the Department of Urology, Wakayama Medical College during the 22 years from 1972 to 1994. The follow-up period ranged from 4 days to 15 years, with a mean of 27.3 months. The primary disease was bladder cancer in 68 patients, uterine cancer in 23 patients, other pelvic malignancies in 11 patients and benign disease in 7 patients. We used 4 types of ureterocutaneostomy; transureteroureterocutaneostomy was done in 13 patients, bilateral ureterocutaneostomy through a single stoma in 30 patients, bilateral ureterocutaneostomy with two stomas in 4 and unilateral ureterocutaneostomy for one available kidney in 62 patients. The construction of stoma was done according to inverted U of Z-shaped skin flap method (30 cases), everted nipple stoma (37 cases) and Toyoda's method (42 cases). We evaluated the stomal condition in 72 patients who were followed more than 6 months postoperatively. Stomal stricture developed and necessitated periodic dilatation or intubation in 25 cases (34%). A better outcome was obtained in patients with dilatated ureter and everted nipple type stoma but no correlation could be found between the history of irradiation and stomal stricture. Long-term outcome of ureterocutaneostomy in 70 patients (129 renal units) was, compared to that of ileal conduit urinary diversion in 124 patients (248 renal units). Postoperative urographic findings showed progressive hydronephrosis in 14 renal units (23%) in the ureterostomy group, while 22 renal units (9%) in the ileal conduit group. However, there was no case of deterioration of renal function which was evaluated by BUN and creatinine in spite of progression of hydronephrosis. The incidence of urinary complications such as pyelonephritis and renal calculus in the successful ureterocutaneostomy group was less than that in the ileal conduit group.

Adolescent↗
PubMed1995

Long-term results after conservative aortic valve repair for aortic regurgitation with ventricular septal defect.

Aortic valve repair was performed in 61 patients having aortic regurgitation (AR) associated with ventricular septal defect (VSD). Preoperative regurgitation was classified according to the Sellers' classification and grade I was in 3 patients, grade II in 19, grade III in 34, and grade IV in 5 patients. Forty-six patients underwent only plication of aortic valve, and in 15 patients the commissuroplasty was added to reinforce the free edge of the cusp. Furthermore, aortoplasty (aortic annuloplasty) was performed in 11. Actuarial survival rate and freedom from reoperation rate were 91.6% and 87.2%, respectively at 10 years after the initial repair. The rate of freedom from deterioration for 22 patients showing grade I or II of AR before the initial operation was 86.4% at 1 year, 76.7% at 5 and 10 years, while the rate for 36 patients with grade III or more severe AR was 91.7% at 1 year, 77.4% at 5 years and 63.9% at 10 years. The rate at 10 years after operation between the two groups was different significantly (p < 0.05). Twenty among 22 patients having grade I or II of AR before operation were in NYHA class I, while 23 of 30 survivors with grade III or IV of AR were in class I, 6 in class II, and 1 in class III. Eight patients received reoperation and four of them underwent repeated conservative aortic valve repair, and one received aortic valve replacement at reoperation. Five of 7 survivors with reoperation improved in NYHA class I and 2 in class II. These results suggested that careful follow-up was required especially for the first 10 years after the initial operation in patients showing preoperative severe AR and receiving aortic repair.

Adolescent↗
PubMed1995

Detachment of desmosomes in a microcystic meningioma.

This report demonstrates the detachment of desmosomes in the microcystic area of a frontal convexity meningioma removed from a 69-year-old woman. Well-developed interdigitations of the tumor cell processes with numerous desmosomes and with narrow extracellular spaces were characteristic features of the solid area of the meningioma. By contrast, the microcystic area of the tumor had markedly distended extracellular spaces. Various stages in the separation of desmosomal attachments were seen in this area. The observed configurations ranged from the widening of opposing junctions to the formation of large cavities where hemidesmosome-like structures were evident. The latter lacked basal lamina, and are considered to represent a transition leading to the loss of desmosome, and thus involved in the enlargement of the extracellular space in microcystic meningiomas.

Aged↗
PubMed1995

Brain tumor: immunohistochemical studies on the stress-response proteins, p53 protein and proliferating cell nuclear antigen.

This retrospective immunohistochemical study compares the expression of five stress-response (heat-shock) proteins (srp's) [srp 90, srp 72, srp 27, alpha B-crystallin and ubiquitin], p53 protein and proliferating cell nuclear antigen (PCNA) in 118 primary brain tumors and 21 carcinoma metastases to the central nervous system. Serial sections of formalin-fixed, paraffin-embedded tissues were used. Most astrocytomas (9/13), ependymomas (5/5), glioblastoma multiforme (GBM) (11/12), schwannomas (19/21), meningiomas (22/23) and breast carcinoma metastases (Br-Mt) (9/10), and some medulloblastomas (5/15), primitive neuroectodermal tumors (PNETs) (5/11), pituitary adenomas (4/7) and lung carcinoma metastases (6/11), but none of 10 oligodendrogliomas had tumor cells that expressed one or more (up to five) srp's. The percentage of tumors with p53-positive cells was variable; the proportion was highest among srp-expressing GBMs (mean: 16.1%) and Br-Mts (mean: 15.3%). The mean PCNA-labeling index (LI) also varied, ranging from 1.2% in the group of pituitary adenomas to 24.5% in Br-Mts, with GBMs (20.4%) and medulloblastomas (18.4%) approaching the latter value. PCNA-LI was higher in the astrocytomas, GBMs, medulloblastomas and PNETs that expressed srp's than in those did not. A high proportion of p53-positive cells (31.3 to 59.0%) and the highest PCNA-LIs (41.0 to 49.0%) were seen in two GBMs and one Br-Mt that expressed all five srp's. We conclude that primary and metastatic tumors of the brain produce one or more stress-related proteins, and that a variable proportion of the tumor cells have immunohistochemically-detectable p53, the expression of which may depend, at least in part, on the growth potential of a given tumor.

Brain Neoplasms↗
PubMed1995

[Bleeding from unruptured dissecting aneurysm in the vertebral artery after proximal clipping].

This is a case report of a patient with unruptured dissecting aneurysm in the vertebral artery that bled after being treated by proximal clipping. A 53-year-old male was admitted to our hospital due to transient right hemiparesis which occurred 20 days prior to his admission. He had been medicated for hypertension for the previous 33 years. CT scan and MRI showed lacunar infarction in the left corona radiata, and an aneurysm was accompanied with clot in the prepontine cistern. Angiography revealed a dissecting aneurysm in the right intracranial vertebral artery. His right hemiparesis was derived from infarction in the left corona radiata. It was likely that the dissecting aneurysm might rupture in the future. Proximal clip ping was performed to prevent rupture of the aneurysm. After clipping of the right vertebral artery distal to the PICA, the wall of the aneurysm appeared to be drawn toward the clip blades and to be tensed by the blades. Four hours after the operation, he complained of severe headache, and experienced a sudden loss of consciousness and the immediate development of a deep comatose state. CT scan disclosed massive SAH in the right cerebellopontine and basal cistern. Repeat angiography demonstrated that the aneurysm was not visualized and the right vertebral artery distal to the aneurysms was opacified through the left vertebral artery. Ventricular drainage was performed, but the patient died on the 20th day after bleeding. It was suspected that the aneurysmal clip might have produced shear force on the weak adventitia of the dissecting aneurysms and that the intra-aneurysmal pressure might have increased because of blood back-flow via the contralateral vertebral artery after the proximal clipping.

Aortic Dissection↗
PubMed1994

Cu/Zn superoxide dismutase-like immunoreactivity in Lewy body-like inclusions of sporadic amyotrophic lateral sclerosis.

Cu/Zn superoxide dismutase (SOD)-like immunoreactivity (LI) was found within Lewy body-like inclusions (LBIs) in the spinal cords of patients with sporadic amyotrophic lateral sclerosis (ALS) by using an antibody to human Cu/ZnSOD. LBIs were detected in the anterior horn cells in 10 of 20 patients with sporadic ALS. In each of these patients, 7 to 60% of LBIs showed Cu/ZnSOD-LI. No Cu/ZnSOD-LI was detected in intact neurons and glia in the 20 ALS patients, as well as in these cells in 10 normal control individuals. The skein-like inclusions and Bunina bodies, which were found in all of the 20 ALS cases, showed no Cu/ZnSOD-LI. Thus, Cu/ZnSOD appears to play roles in the production and/or degradation process of LBIs.

Aged↗
PubMed1994

Altered synaptophysin-immunoreactive pattern in human olivary hypertrophy.

We examined the inferior olivary nucleus from four cases of olivary hypertrophy and six control cases immunohistochemically with an anti-synaptophysin (SYP) antibody. Our study revealed the altered SYP-immunoreactive pattern in the hypertrophied olives, consisting of an increased number of SYP-immunoreactive dots on neuronal cell bodies in spite of its decreased immunoreactivity in the neuropil. Because SYP is a marker protein for presynaptic vesicles, presynaptic terminals in the inferior olivary nucleus seem to change their distribution during the course of olivary hypertrophy.

Aged↗
PubMed1994

Electron microscopy of the blood-brain barrier in disease.

The anatomical site of the blood-brain barrier (BBB) is at the capillary endothelium mainly, with some contribution from astrocytes. Electron microscopic observations of endothelial cells and perivascular astrocytes comprising the BBB in brain edema and other pathological conditions are reviewed in this article. The tight junctions of cerebral endothelial cells open under several conditions such as infusion of hyperosmolar solutions. Pinocytotic vesicles increase under various pathological conditions and fenestrae appear in blood vessels of certain brain tumors and several non-neoplastic lesions. Inflammatory cells penetrate between or through endothelial cells. In long standing lesions, endothelial cells containing various tubular structures such as Weibel-Palade bodies proliferate. Other alterations include surface infoldings of endothelial cells and fluid diffusion through damaged endothelium. Astrocytic alterations include abnormal junctions between astrocytic processes in certain gliomas. In vivo and in vitro studies suggest that astrocytes maintain or develop certain functions of BBB. As the BBB is disrupted, edema fluid infiltrates the brain parenchyma. Because the white matter consists of nerve fibers without demonstrable junctions, it invades between nerve fibers. In the gray matter, expansion of the fluid is limited by complicated anatomical structures. In myelinated nerve fibers, edema fluid accumulates in five separate compartments of extracellular space.

Animals↗
PubMed1994

The mutant Eisai hyperbilirubinemic rat is resistant to bile acid-induced cholestasis and cytotoxicity.

We investigated bile flow and biliary excretion of bile acids in the Eisai hyperbilirubinemic rat, a Sprague-Dawley mutant rat with conjugated hyperbilirubinemia, using both in vivo and in vitro models. In vivo bile flow was lower in Eisai hyperbilirubinemic rats than in the control rats before and after taurocholate was infused. After taurocholate was infused, bile acid output was similar in the Eisai hyperbilirubinemic rats and control rats. In the isolated perfused rat liver, biliary excretion of bile acids was higher in the Eisai hyperbilirubinemic rats than in the control rats after a high-dose infusion of taurocholate (0.33 mumol/min/gm liver). Infusion of taurochenodeoxycholate (0.22 mumol/min/gm liver) did not produce cholestasis and did not reduce the biliary excretion of bile acids in the Eisai hyperbilirubinemic rats. Taurochenodeoxycholate significantly increased the phospholipid/bile acid molar ratio and slightly reduced bile acid-induced alkaline phosphatase output into bile. The release of lactate dehydrogenase from the perfused liver 30 min after the start of the taurochenodeoxycholate infusion was 10 times lower in the Eisai hyperbilirubinemic rats than in the control rats (2.0 +/- 0.8 vs. 28.7 +/- 6.8 mU/min/gm liver). When the isolated perfused rat liver was infused with a 1-min pulse of horseradish peroxidase (25 mg), we observed an early and late peak of biliary excretion of horseradish peroxidase. The Eisai hyperbilirubinemic rats showed a significant increase in the late peak.(ABSTRACT TRUNCATED AT 250 WORDS)

Alkaline Phosphatase↗
PubMed1994

Histological changes of implanted collagen material during bone induction.

Studies were made on the fate of implanted material during bone induction. Mixtures of 1 mg of crude bone morphogenetic protein (BMP), or bovine serum albumin as a control, and 1.5 mg of bovine collagen, were pressed into discs and implanted under the fascia of the rectus abdominus muscle of rats. The tissues with implants were fixed 7, 10, and 14 days later and examined histologically. On day 7 after implantation, the implant was surrounded and invaded by alkaline phosphatase-positive cells. New bone and cartilage were seen at the periphery of the implant. In the regions of calcified cartilage and bone, these osteogenic matrices were intermixed with the implant. The mineral deposits were seen by electron microscopy not only on the osteogenic matrices but also on the implanted collagen. On day 14, the bone had spread to the center of the implant. No osteogenesis or chondrogenesis was seen in control implants. It was concluded that the calcification occurred on the implanted collagen during bone induction, and that it was related to successive bone formation and remodeling.

Alkaline Phosphatase↗
PubMed1994

Demonstration of neurofibrillary tangles and neuropil thread-like structures in spinal cord white matter in parkinsonism-dementia complex on Guam and in Guamanian amyotrophic lateral sclerosis.

This report concerns the demonstration and distribution of neurofibrillary tangles (NFTs), immunoreactive neuropil thread-like structures and dots in the spinal cord gray and white matter of six patients with parkinsonism-dementia complex on Guam and five patients with Guamanian amyotrophic lateral sclerosis (ALS). A monoclonal antibody to Alzheimer NFTs was used. NFTs were found in the spinal cord gray matter and white matter and all patients had immunoreactive neuropil thread-like structures and dots in the gray matter as well as in the white matter. They were particularly numerous in the lateral funiculus of patients with Guamanian ALS.

Amyotrophic Lateral Sclerosis↗
PubMed1994

Comparative study of spinal cord ubiquitin expression in post-poliomyelitis and sporadic amyotrophic lateral sclerosis.

This study addresses the suggested possible pathogenetic relationship between the late-onset muscular atrophy in patients with the prior diagnosis of poliomyelitis and amyotrophic lateral sclerosis (ALS). For this purpose we applied immunohistochemical techniques to determine the presence of pathological structures that were stained for ubiquitin (a protein involved in degenerative processes) in the spinal cords of patients with a history of poliomyelitis and compared the results with those of ALS, a condition in which cytoplasmic ubiquitin-positive inclusions are invariably found in the anterior horn cells. Our results indicate that post-poliomyelitis patients have no ubiquitin-reactive inclusion bodies in these cells; however, some immunopositive globular and cord-shaped structures are seen in less-affected areas. Similar structures were also found in the spinal cords from patients with ALS and from normal individuals. Our findings would suggest that the pathogenesis of late muscular atrophy in post-poliomyelitis patients is dissimilar to that of ALS.

Aged↗
PubMed1994

The effects of intravesical chemoimmunotherapy with epirubicin and bacillus Calmette-Guérin for prophylaxis of recurrence of superficial bladder cancer: a preliminary report.

The effects of intravesical chemoimmunotherapy with epirubicin and bacillus Calmette-Guérin (BCG) for prophylaxis of recurrence of superficial bladder cancer (pTa, pT1) were investigated in 29 patients aged a median of 70 years between January of 1991 and May of 1993. The patients received intravesical instillation of 40 mg epirubicin immediately after transurethral resection (TUR) of the bladder cancer. At 1 week after TUR, 80 mg Tokyo-strain BCG was instilled into the bladder once a week for 6 weeks. Thereafter, the patients were followed by cystoscopy and urinary cytology at 3-month intervals until recurrence was detected. Of the 29 patients, 28 had no evidence of disease over a mean follow-up period of 20 months. The 1 case of recurrence occurred at 3 months after TUR and that patient died of cancer progression. The simple recurrence rate was 3.5% after therapy. According to the person-years method, the number of recurrent tumors per 100 patient-months was 0.17. The cumulative nonrecurrence rate determined for all cases was 96.5% at 30 months. Adverse reactions, including urinary frequency, urgency, and miction pain, among others, were observed in 27 patients (93%). Only 1 patient was withdrawn from the treatment because of severe bladder-irritation symptoms due to the BCG instillation. The intravesical chemoimmunotherapy with epirubicin and BCG seemed to be effective for prophylaxis of recurrence of superficial bladder cancer.

Administration, Intravesical↗
PubMed1994

Limited effectiveness of FK506 administration for ongoing rejection in heterotopic rat heart transplantation.

A comparison was made of the histological findings for myocardial tissue of heterotopic transplanted rat hearts administered with FK506. ACI rats were used as donors and Lewis rats as recipients. FK506 was used for 6 days except for group I (control group). Group II received 0.32 mg/kg/day of FK506 from the day of operation while group III was given the same dosage from the 4th day after transplantation. Group IV was given 1.28 mg/kg/day of the agent from the day of grafting and group V received the same dose from the 4th postoperative day. The graft survival time was longer for all groups given FK506, but was significantly longer only for groups administered with FK506 from the day of operation. Histological studies performed 10 and 20 days after transplantation showed that a moderate rejection was seen in about half of the grafts receiving FK506 from the 4th day after grafting. An ultrastructural study of these cases showed that infiltrating large lymphocytes still remained in the interstitial tissues and that the cytoplasmic organelles of the myocytes had been focally destroyed. These results suggest that, although FK506 suppressed any further rejection, the effect might be limited and the myocardial changes of the cardiac graft might persist even after administration for ongoing rejection.

Animals↗