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Biomedical subjects

Y Hashimoto

Publications and source records attributed to Y Hashimoto.

At least 469 records · Page 26Linked to original sources
PubMed1998

[New application of ultrasound imaging using contrast agent].

Recently, various ultrasound contrast agent have been developed all over the world. This paper reviewed recent development of some contrast agent and clinical application of new imaging using contrast agent (Enhanced color Doppler Imaging, Harmonic Imaging, Flash Echo Imaging and Loss of Correlation Imaging). These new methods are easily feasible with a clinical ultrasound diagnosis machine for evaluating further information, for example, slow or deeply located lesion's blood flow, furthermore tissue perfusion. Contrast enhanced ultrasound imaging such as Harmonic imaging is enable to evaluate tissue function.

Animals↗
PubMed1998

[Contrast echo imaging on the breast and thyroid cancers].

The utility of ultrasound color Doppler flow mapping imaging for the differential diagnosis on the breast and thyroid tumors had already reported in 1991. Ultrasound contrast agent, SH/TA 508 (Levovist; Schering AG, Germany), had already finished clinical trials in Japan and reported the result phase II, III. On the breast and thyroid lesions, the utility of this contrast agent are safety and usefulness for the accurate diagnosis by the ultrasound color Doppler examination. Throughout of these clinical trials, a quit new ultrasound Doppler imaging methods had been developed, Harmonic Imaging and acoustic emission mode. As the result, ultrasound contrast agent is useful not only for the conventional color Doppler diagnosis but also for the developing of new diagnostic imaging methods.

Breast Neoplasms↗
PubMed1998

Efflux of intracellular alpha-ketoglutarate via p-aminohippurate/dicarboxylate exchange in OK kidney epithelial cells.

The involvement of intracellular alpha-ketoglutarate (alpha-KG) in p-aminohippurate (PAH) transport was investigated in OK kidney epithelial cells. Efflux of intracellular alpha-KG from the OK cells to the basolateral side was increased by applying PAH to the basolateral side of the cells. In contrast, the intracellular alpha-KG concentration was not influenced by the addition of PAH. The alpha-KG efflux across the basolateral membrane induced by PAH was higher than that across the apical membrane. Probenecid inhibited the PAH-dependent alpha-KG efflux. The alpha-KG efflux to the basolateral side was saturable with increasing concentration of PAH in the basolateral medium. Antimycin A, a metabolic inhibitor, inhibited [14C]PAH uptake across the basolateral membrane of OK cells in a dose-dependent manner. In addition, both the alpha-KG efflux induced by PAH and the intracellular alpha-KG concentration were decreased by antimycin A dose-dependently. These results directly show that alpha-KG generated by intracellular metabolism is effluxed via PAH/dicarboxylate exchange in the basolateral membrane of OK cells.

Antimycin A↗
PubMed1998

[A case of intracranial tuberculoma followed by MRI].

A 62-year-old woman with pulmonary tuberculosis was admitted to our hospital. She was completely neurologically free at admission and her CSF was normal. Brain MRI with Gd-DTPA enhancement demonstrated two mass lesions with ring-enhancement in the left temporal lobe and the right frontal lobe. The left temporal lesion had a bright central core with hypointense periphery on T2 weighted image. Extended hyperintense area was observed around this lesions, which represented brain edema. On T1 weighted image, the central core was demonstrated hypointense and its periphery was isointense. After starting antituberculous therapy, MRI revealed paradoxical expansion of left temporal lesion and neurological symptoms worsened temporarily, but, eventually the intracranial lesions diminished in size and disappeared, and the symptoms improved. So we diagnosed her as having intracranial tuberculoma. By long-term following up with MRI, we observed that the central core of the left temporal tuberculoma had changed gradually to hypointense on T2 weighted image and hyperintense on T1 weighted image respectively. We thought that the change of the central core on MRI represented organization of caseated necrosis.

Antitubercular Agents↗
PubMed1998

[Asymptomatic cerebral infarction associated with a patent foramen ovale and atrial septal aneurysm].

We reported two young adults (a 42-year-old female and a 45-year-old male) with tension type headache who had a patent foramen ovale and atrial septal aneurysm demonstrated by transesophageal echocardiography, associated with asymptomatic cerebral infarctions. There were multiple subcortical infarctions in the frontal and parietal lobes in case 1, and cerebral infarctions in the right corona radiata, head and body of the caudate nucleus, and putamen in case 2. The two cases did not have hypertension, diabetes mellitus, hyperlipidemia, cardiac diseases detected by electrocardiography and transthoracic echocardiography, and abnormality of intracranial and extracranial arteries by ultrasound sonography and cerebral angiography. Transeosophageal echocardiography revealed atrial septal aneurysm, and showed right-to-left shunt (patent foramen ovale) by Valsalva maneuver. Two cases were diagnosed as paradoxical cerebral embolism associated with a patent foramen ovale. If asymptomatic cerebral infarctions are cryptogenic stroke, a patent foramen ovale and atrial septal aneurysm should be examined by transesophageal echocardiography with Valsalva maneuver.

Adult↗
PubMed1998

Intranasal administration of demopressin (DDAVP) for type 1 and type 2A von Willebrand disease.

Desmopressin was administered intranasally to seven patients with von Willebrand disease (type 1: 4 patients, type 2A: 3 patients) to assess the response and safety. von Willebrand factor antigen ranged from 8% to 60% before treatment and increased significantly after intranasal DDAVP administration (the median relative increase: two- to threefold). Factor VIII levels also increased substantially over baseline levels after intranasal administration. Before treatment ristocetin cofactor activity was 32 +/- 12% in patients with type 1 vWD and 9 +/- 5% in patients with type 2A vWD. After intranasal administration, the levels of ristocetin cofactor activity increased to 56 +/- 21% and 29 +/- 9%, respectively. The bleeding time was normalized in 86% of the patients. The abnormality of vWF multimers in type 1 vWD returned more or less to normal after intranasal DDAVP administration whereas that in type 2A vWD did not. The intranasal administration of DDAVP is safe and effective for minor bleeding episodes and is adaptable for home use in patients with type 1 and type 2A vWD.

Administration, Intranasal↗
PubMed1998

Absorption of intubation-related lidocaine from the trachea during prolonged cardiopulmonary resuscitation.

The purpose of this study was to determine whether lidocaine is absorbed from the trachea during the artificial circulation of cardiopulmonary resuscitation. The tissue distribution of lidocaine was investigated in eight individuals (Cases 1-8) who underwent cardiopulmonary resuscitation before being pronounced dead. In Cases 1-4, there was no restoration of heart beat during cardiopulmonary resuscitation. Heart massage had been continued for 5 min in Cases 1 and 2, and for 60 min in Cases 3 and 4. Relatively high concentrations of lidocaine (more than 0.1 mg/L) were detected in the blood left in the heart and/or in the large thoracic vessels in the four cases. In Cases 1-3, a large proportion of the lidocaine detected in these blood samples may have diffused from the trachea after cessation of cardiopulmonary resuscitation since no lidocaine was detected in the cerebrospinal fluid, cerebrum, liver, right kidney, and/or right femoral muscle. In Case 4, however, tracheal lidocaine was thought to have been absorbed during cardiopulmonary resuscitation because 0.167-0.340 mg/L or mg/kg lidocaine was detected in the cerebrospinal fluid, liver, right kidney, and right femoral muscle. This was substantiated in experiments performed in rabbit carcasses given 50 microL/kg Xylocaine jelly (a 2% lidocaine hydrochloride preparation) intratracheally, followed by rhythmical thoracic compressions (100-150 times per minute) for 60 min. A possible reason for lack of absorption of lidocaine from the trachea of Case 3 during a 60-min cardiopulmonary resuscitation procedure may have been that effective blood circulation was not obtained during cardiopulmonary resuscitation because of bleeding and pulmonary collapse. Cases 5-8 survived for 3 h to 10 days after successful cardiopulmonary resuscitation; it was obvious that lidocaine was distributed to the tissues under the influence of the natural circulation. The kidney to liver lidocaine ratio in Case 4 (0.8) was much lower than that in Cases 5-8 (1.3-4.6), although the lidocaine ratio in the blood in the left ventricle when compared to blood in the right ventricle was similar in the five cases. The kidney to liver lidocaine ratio may be helpful in judging whether the lidocaine detected was absorbed during the artificial circulation of cardiopulmonary resuscitation or naturally. Additionally, postmortem diffusion of tracheal lidocaine into the blood in the left ventricle was much greater than into the blood in the right ventricle due to their anatomical location during a supine position. The pattern of tissue distribution of lidocaine gives useful information on the state of decedents during cardiopulmonary resuscitation.

Absorption↗
PubMed1998

[Cerebral embolism with hemiballism due to putaminal lesion].

A 66-year-old man was admitted to our hospital because of hemiballism of his left extremities. The hemiballism disappeared soon after beginning therapy with haloperidol and chlorpromazine. X-ray CT brain scan on day 3 showed infarction in the right putamen and the right parietal lobe. Cerebral angiography on day 9 was normal. Transesophageal echocardiography revealed no abnormality except for an atrial septal aneurysm. Transcranial color-flow imaging demonstrated high intensity transient signal (HITS) with Valsalva maneuver. Paradoxical embolism was, therefore, thought to have caused the patient's brain infarction. It was speculated that the hemiballism was caused by disinhibition of the cortex resulting from loss of negative feedback in the motor system due to the putaminal lesion. It is necessary to treat hemiballism using an appropriate therapy to prevent exacerbation.

Aged↗
PubMed1998

[Spinal anesthesia in a patient with spina bifida occulta].

A 32-year-old woman with spina bifida occulta was scheduled for hemorroidectomy under spinal anesthesia. Preoperatively, computed tomography and magnetic resonance imaging (MRI) were performed. The MRI demonstrated the conus medul laris reaching the L 3 level and a lipoma connected with conus medullaris intrathecally. Spinal anesthesia was done successfully at the L 3-4 interspace using 0.3% dibucaine 1.2 ml with 5% glucose 0.8 ml. Postoperatively she showed no neurologic complications. With exact anatomical findings of MRI, spinal anesthesia can be safely performed for patients with spina bifida occulta.

Adult↗
PubMed1998

Construction of a cosmid library and physical mapping of Bombyx mori nucleopolyhedrovirus genome.

Bombyx mori nucleopolyhedrovirus (BmNPV) DNA was partially digested with BamHI and BglII, or EcoRI, and cloned into the cosmid pWE15. Eight cosmid clones possessing viral DNA fragments with a size range from 34.9 kb to 45.1 kb were obtained, and they covered the entire viral DNA sequence. Using the cosmid library and plasmid libraries obtained previously, physical maps of BmNPV DNA were constructed for EcoRI, SmaI, PstI, SacI and SacII.

Baculoviridae↗
PubMed1998

[Etiological studies on 17 cases of retinal artery occlusion and 16 cases of amaurosis fugax].

Here we present etiological studies on 17 patients (12 males, 5 females, mean age 64 +/- 13 years) with central retinal artery occlusion and branch retinal artery occlusion, and 16 patients (8 males, 8 females, mean age 62 +/- 13 years) with amaurosis fugax who were admitted to our hospital between April 1993 and May 1997. In all patients, carotid ultrasonography and cerebral angiography were performed to clarify the extent of carotid artery disease ipsilateral to the retinal artery occlusion and amaurosis fugax. All patients had clinical assessment of cardiac function and electrocardiogram, and most patients had transthoracic echocardiography, and transesophageal echocardiography as they were required. Arterial stenosis over 50% of the diameter, and occlusion of the internal carotid artery ipsilateral to symptomatic eye were more frequent in retinal artery occlusion than in amaurosis fugax. Two patients with retinal artery occlusion had transient atrial fibrillation, and one had patent foramen ovale with atrial septal aneurysm. One patient with amaurosis fugax had transient atrial fibrillation, and another patient had mechanical prosthetic heart valve. Two patients had antiphospholipid antibody, and one had dysfibrinogenemia. We recommended to investigate internal carotid artery in the patients with retinal artery occlusion, because occlusive disease ipsilateral to the symptomatic eye is more frequent and severe in retinal artery occlusion than in the cases of amaurosis fugax.

Aged↗
PubMed1998

Medicolegal implications of drugs and chemicals detected in intracranial hematomas.

The purpose of this study was to determine how drug findings in intracranial hematomas should be assessed in forensic autopsy cases. Six cases in which intracranial hematomas containing drugs and chemicals were detected were examined in this study. Of the six cases, five were positive for drugs and chemicals that had been self-administered by the victims prior to injury. Post-traumatic time interval from injury to death was in the range 10 to 65 h. In two individuals who were positive for norephedrine or toluene, the concentrations of these substances were much higher in the intracranial hematomas than in heart blood. In an individual who was positive for phenobarbital, its concentration was only a little higher in the intracranial hematoma than in heart blood. In the remaining two cases, substantial quantities of ethanol were detected in the intracranial hematomas, but little ethanol was detected in heart blood. In three cases, some drugs were administered at hospital after the injuries. The time interval from the initial drug administration to death was 19 to 60 h. In two individuals given phenytoin and/or lidocaine intravenously, substantial amounts of these drugs were detected in the intracranial hematomas. In an individual given diazepam intravenously, a substantial quantity of diazepam was detected in heart blood, but not in the intracranial hematoma. Toxicological analysis of intracranial hematomas may be useful not only for determining whether individuals were under the influence of ethanol at the time they were injured, but also for detecting pre-traumatic usage of other drugs and chemicals. However, the medical record should be reviewed thoroughly from a toxicological view point if victims underwent medical treatment prior to death because drugs administered for the purpose of medical treatment can disseminate into preexisting intracranial hematomas, depending on the size of the hematomas.

Adult↗
PubMed1998

[A case of paradoxical brain embolism in a 17-year-old boy].

A 17-year-old healthy high school boy suddenly suffered from consciousness disturbance immediately after a karate match. His neurological findings on admission were consciousness disturbance, motor aphasia, right hemiparesis, and right Babinski reflex. Cerebral angiography showed occlusion of the precentral branch of the left middle cerebral artery, and X-ray CT scan on the second day revealed low density area in its territory. No abnormality was found on transthoracic echocardiography or Holter ECG. Contrast transesophageal echocardiography with Valsalva maneuver was performed twice (the 2nd and the 14th day), and patent foramen ovale (PFO) was found only on the second trial. It was supposed that paradoxical embolism had occurred. Transesophageal echocardiography is necessary for the embolic patients of unknown origin, especially young adults. To find PFO, it is important to repeat contrast transesophageal echocardiography carefully. if it is negative on the first trial.

Adolescent↗
PubMed1998

Analysis of defective genomes of bombyx mori nucleopolyhedrovirus generated by serial undiluted passage in cell culture.

Viral DNA was extracted from cells infected with bombyx mori nucleopolyhedrovirus (BmNPV) D1 strain after 34 serial undiluted passages (P34). P34 DNA was subjected to restriction analysis and Southern blot hybridisation using standard D1 DNA and P34 DNA of BmNPV as probes. Based on hybridisation profiles, the BmNPV DNA regions retained in the P34 DNA were localised on HindIII and PstI restriction maps. Two regions of BmNPV DNA located at 0-12.8 and 40.2-65.0 map unit (m.u.) were highly conserved in P34 DNA. These regions contained two of three interspersed homologous sequences (ihss), but only one of five homologous regions (hrs). This suggests that ihss may have an essential role in BmNPV replication.

Animals↗
PubMed1998

[Evaluation of transcranial-color flow imaging in detection of right-to-left intracardiac shunts].

We performed transesophageal echocardiography (TEE) and transcranial-color flow imaging (TC-CFI) in 38 patients (25 men, 13 women, mean age 51.5 years old) with cerebrovascular or cardiac disease in order to evaluate an accuracy in diagnosing right-to-left shunts (RLS) in the heart by TC-CFI as compared to TEE findings. We rapidly injected a mixture of 9 ml of cold saline and 1.0 ml of air into the antecubital vein during Valsalva maneuver. In TEE study, we took RLS positive when interatrial shunting of contrast microcavitations into the left atrium was visualized after complete opacification of the right atrium. In TC-CFI study, we considered RLS positive when we detected the high intensity transient signals (HITS) on the middle cerebral artery. The both studies were positive in 15 patients and negative in 19. Two patients were positive in TC-CFI and negative in TEE while the other two patients were negative in TC-CFI and positive in TEE. Therefore, the sensitivity of TC-CFI in diagnosing RLS was 88%, the specificity 90%, and the accuracy 89%. It seems that TC-CFI is a useful tool to estimate the RLS.

Aged↗
PubMed1998

Transport of quinolone antibacterial drugs in a kidney epithelial cell line, LLC-PK1.

The transport of quinolone antibacterial drugs by LLC-PK1 monolayers was examined to characterize the renal tubular secretion of these drugs. The transcellular transport of levofloxacin and grepafloxacin from the basolateral to apical side was larger than the transport in the opposite direction. The basal-to-apical transcellular transport and uptake from the basolateral side of levofloxacin showed concentration dependent saturation with an apparent Michaelis constant (Km) of 0.6 and 13 mM, respectively. Various quinolones (1 mM) inhibited the transcellular transport of levofloxacin, and this inhibition was accompanied by a marked increase of cellular accumulation. These results indicated that quinolones interacted more strongly with the transport system on the apical than the basolateral membrane. Neither tetraethylammonium nor cyclosporin A affected the basal-to-apical transcellular transport and accumulation of levofloxacin. The basal-to-apical transcellular transport of levofloxacin was not influenced by either lowering the pH of the apical side or pretreatment of apical membrane with p-chloromercuribenzene sulfonate. These findings indicate that quinolones are specifically transported from the basolateral to apical side by LLC-PK1 monolayers and have higher affinity for the transport system in the apical membrane, a system distinct from H+/organic cation antiport system.

4-Chloromercuribenzenesulfonate↗
PubMed1998

[Pain management of private hospital in home care].

Pain management is in need of several approaches. Cancer pain attracts our attention but pain management of benign disease is very important also. It is indispensable to maintain the quality of home care.

Analgesics↗