Biomedical subjects

I Nakano

Publications and source records attributed to I Nakano.

At least 127 records · Page 7Linked to original sources

PubMed1998

Bulbar palsy in senile onset familial amyloid polyneuropathy (30Val-->Met): transthyretin-amyloid deposits in the hypoglossal nerve root.

Japanese familial amyloid polyneuropathy (FAP type I) is characterized clinically by autonomic and sensorimotor polyneuropathy. Bulbar palsy or lower cranial amyloid neuropathy has not been reported in this disease. We report a 72-year-old man with senile onset FAP type I, who developed bulbar palsy and sensorimotor polyneuropathy without autonomic failures. He noticed dysesthesia and muscle weakness in the feet at the age of 67 years. Neurological examination showed bulbar signs and sensorimotor polyneuropathy, but not autonomic neuropathy. Electromyography showed denervation in the tongue and extremities. Sural nerve biopsy revealed a profound reduction of myelinated fibers. Neuropathological studies indicated axonal degeneration and transthyretin-amyloid deposits in the peripheral nerves and hypoglossal nerves or roots. DNA analysis demonstrated transthyretinMet30 mutation. We provide the novel possibility that bulbar palsy, due to amyloid neuropathy, can occur in FAP type I. Copyright Rapid Science Ltd

Journal Article↗

PubMed1998

Prophylactic endoscopic ligation of high-risk oesophageal varices in a cirrhotic patient with severe haemophilia A.

One of the main complications in cirrhosis is haemorrhage from oesophageal varices. It is serious and often fatal, especially in cirrhotic patients with haemophilia. We describe the use of endoscopic variceal ligation (EVL) for prophylaxis of oesophageal variceal bleeding in a high-risk patient, a 40-year-old Japanese man, with severe haemophilia A and liver cirrhosis caused by hepatitis C virus. He had large, coil-shaped varices with a red colour sign, predicting the likelihood of haemorrhage. Administration of omeprazole and factor VIII concentrate achieved rapid healing of the post-EVL ulcers and prevented bleeding from them. Four EVL sessions eradicated oesophageal varices completely, and he has had no recurrence of varices for 2 years, indicating that the procedure was of considerable benefit.

Adult↗

PubMed1998

Serum hyaluronan as a marker of liver fibrosis in hemophiliacs with hepatitis C virus-associated chronic liver disease.

We measured serum type III procollagen peptide, type IV collagen (IV-C), and hyaluronan (HA) in 36 hemophiliacs with hepatitis C virus (HCV)-related chronic liver disease. We also measured these markers in 19 interferon (IFN)-treated patients before and after a 6-month course of IFN-alpha. The serum concentrations of IV-C and HA were correlated with the stage of fibrosis (IV-C r = 0.38; HA r = 0.78). These markers fell only in complete responders showing sustained clearance of serum HCV RNA by IFN. These results suggest that, in hemophiliacs with chronic liver disease, serum HA measurement might be an alternative to liver biopsy and reflect the response to IFN.

Adolescent↗

PubMed1998

Serum levels of soluble intercellular adhesion molecule-1 and soluble vascular cell adhesion molecule-1 in asymptomatic carriers of hepatitis C virus.

High levels of serum-soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1) have been noted in patients with chronic hepatitis C. This study aimed to measure serum levels of sICAM-1 and sVCAM-1 in asymptomatic hepatitis C virus carriers and clarify the clinical significance of measuring soluble forms. Serum levels of sICAM-1 were significantly higher than in healthy controls but serum sVCAM-1 levels did not differ statistically from those in healthy controls. Liver biopsy obtained from 12 asymptomatic hepatitis C virus carriers showed evidence of hepatitis. Estimating sICAM-1 and sVCAM-1 in asymptomatic carriers may be helpful, especially in cases in which liver biopsy is not possible.

Adult↗

PubMed1998

Diagnosis and staging of pancreatic cancer by endoscopic ultrasound.

The aim of this study was to evaluate the usefulness of and problems associated with endoscopic ultrasonography (EUS) in the diagnosis and pre-operative staging of pancreatic cancer. 96 patients suspected of having pancreatic cancer were pre-operatively examined with EUS. 37 of these 96 patients had pancreatic cancer. Results of the EUS imaging were compared with findings of histology and/or surgery, and the patient's clinical course. The sensitivity and specificity of EUS for diagnosing pancreatic cancer were 89% and 97%, respectively. EUS had excellent sensitivity regardless of tumour size or location. EUS was accurate (90%) in determining tumour size in pancreatic cancers less than 3 cm in maximum diameter, but not for tumours greater than 3 cm (30%). The accuracy of tumour (T) and nodal (N) staging were 64% and 50%, respectively. EUS is a promising method for the early diagnosis and pre-operative staging of pancreatic cancers, but requires further refinement.

Adult↗

PubMed1998

Chronic bromvalerylurea intoxication: dystonic posture and cerebellar ataxia due to nonsteroidal anti-inflammatory drug abuse.

Nalon-Ace and other nonsteroidal anti-inflammatory drugs (NSAID) containing bromvalerylurea (BVU) are sold as over-the-counter (OTC) drugs and are obtainable without prescription in Japan. A 32-year-old woman was diagnosed as having chronic BVU intoxication due to habitual use of Nalon-Ace. In addition to cerebellar ataxia and pyramidal signs well known in this condition, she showed an as yet non-described dystonic posture of the neck. Laboratory tests revealed an elevated concentration of serum organic bromide, iron deficiency anemia, and hyperchloremia. Brain magnetic resonance imaging (MRI) revealed definite cerebellar atrophy. We should consider the possibility of chronic BVU intoxication in peculiar neurological cases like ours.

Adult↗

PubMed1998

[An autopsy case of deep cerebral venous thrombosis: serial CT, MRI and pathological findings].

A 17-year-old girl developed vomiting of sudden onset, followed by a state of confusion that progressed rapidly to coma within one day. Laboratory tests indicated iron deficiency anemia and reactive thrombocytosis, but there was no evidence of coagulopathy. There was no history of medication including the contraceptive pill, either. Emergency CT scan without contrast enhancement showed increased density along the course of the vein of Galen and internal cerebral veins. A repeated CT scan without contrast enhancement carried out 24 hours after the onset of the illness confirmed extensive bilateral hypodensity of the thalami, basal ganglia and adjacent white matter. There was also a prominent spontaneous increase in the density of the deep cerebral venous system. MRI was performed 3 days after the onset of the illness, which showed absence of a flow void in the region of the internal cerebral veins and septal veins on T1-weighed images. T2-weighted images showed low intensity in these veins. At autopsy, the bilateral internal cerebral veins were occluded by fresh thrombosis and hemorrhagic infarction was seen in the bilateral thalami.

Adolescent↗

PubMed1998

Cotransduction of tyrosine hydroxylase and aromatic L-amino acid decarboxylase genes into cultured striatal cells using adeno-associated virus vectors.

OBJECTIVE: To examine whether tyrosine hydroxylase (TH) and aromatic L-amino acid decarboxylase (AADC) genes can be cotransduced into the same target striatal cells using adeno-associated virus (AAV) vectors, and to determine whether the cotransduction would result in better biochemical change than the TH gene alone. METHODS: TH and AADC genes were cotransduced into cultured striatal cells with separate AAV vectors. Expressions of TH and AADC were detected by immunocytochemistry; intracellular catecholamine levels were assayed by high-performance liquid chromatography (HPLC). RESULTS: TH and AADC genes were efficiently cotransduced into the striatal cells. Specifically, the coexpression of TH and AADC resulted in more effective dopamine production compared with the TH gene alone. CONCLUSION: Using AAV vectors, coexpression of TH and AADC in the striatal cells might be a useful approach to gene therapy for Parkinson's disease.

Animals↗

PubMed1998

Quasispecies nature of hepatitis C virus (HCV) in patients with chronic hepatitis C with mixed HCV subtypes.

The quasispecies nature of hepatitis C virus (HCV) in patients with mixed HCV subtype infection was compared with that in patients with single HCV subtype infection. The number of HCV quasispecies was compared between 35 patients with mixed HCV subtype infection and 83 patients with single subtype infection. Subtype was determined by primers deduced from the core region and by line probe assay respectively. The number of quasispecies was evaluated by polymerase chain reaction amplification of hypervariable region 1 and by fluorescence single-strand conformation polymorphism analysis. There was no difference in clinical background between patients with mixed subtype infection and patients with single subtype infection. The number of quasispecies in patients with multiple subtype HCV infection was larger than in patients with single subtype HCV infection. The immunologic environments which allow the coexistence of more HCV quasispecies in patients with multiple HCV subtype infection differs from that in patients with single HCV subtype infection.

Adult↗

PubMed1998

Immune responses against hepatitis C virus structural proteins following genetic immunisation.

We have used direct DNA inoculation to study the in vivo induction of both humoral and cellular immune responses to hepatitis C virus (HCV) encoded structural antigens. Following immunisation of mice, immune responses were compared using plasmids encoding full-length or partial HCV gene sequences for the nucleocapsid and envelope E2 proteins. Plasmids encoding secreted or non-secreted forms of the immunogens, including constructs expressing HCV sequences fused with the hepatitis B virus surface antigen (HCV-HBV chimeras), were evaluated. Results indicate that: (i) all constructs induced specific anti-HCV antibodies; (ii) antibody titres ranged from 1:100 to > 1:100,000; (iii) all HCV DNA immunogens induced a predominant Th1 response with the induction of IgG2a antibodies; (iv) the secretion level of the antigens and immune responses was not always correlated and (v) CTL could be detected against both HCV and HBV determinants.

Animals↗

PubMed1998

[Valproic acid relieved marked rigidity in three patients with end-stage parkinsonism].

We applied valproic acid (VPA) on the rigidity of three parkinsonian patients, two with Parkinson disease and one with striatonigral degeneration. They were all at Hoehn and Yahr's stage V and showed marked rigidity. In these patients, effect of L-DOPA had become limited or increasing the dosage of L-DOPA was difficult because of its side effects. Parkinsonian symptoms were assessed by using motor score of Unified Parkinson's Disease Rating Scale. The degree of rigidity in these three patients was markedly decreased with 300-600 mg/day of VPA. The blood level of VPA ranged from 24.8 to 66.5 micrograms/ml, which was relatively low compared with the effective blood level as an anti-epileptic agent. Parkinsonian symptoms other than rigidity, and the increased deep tendon reflexes which were present in the patient with striatonigral degeneration were not affected by VPA. Reduction of L-DOPA intensified rigidity again which had been under control. Trials of VPA on parkinsonism have been reported from two groups (Price PA, et al. 1978; Nutt J, et al. 1979), neither of which has observed any benefit of VPA. The difference of their results and ours seems to depend on the stage of patients; their patients had mild to moderate symptoms, whereas ours were in the end stage with marked rigidity. Since the effect of VPA upon parkinsonism is limited to rigidity, the end-stage patients whose care is difficult due to severe rigidity may obtain the best benefit of VPA. VPA is considered to take effect by activating gamma-aminobutyric acid (GABA) system. Because GABA is a common inhibitory neurotransmitter distributed in the wide areas of the central nervous system, it is difficult to locate the action site of VPA with regard to the amelioration of rigidity. The stretch reflex loop in the spinal cord does not seem to be the action site because no change was noted in deep tendon reflex. GABAergic striatal efferent neurons do not seem to be the sole action site either, because parkinsonian symptoms were not affected except for rigidity. The vestibular nucleus which receives strong GABAergic afferents from cerebellar Purkinje cells is an efficient tonus regulator. Since suppression of the function of the nucleus is known to reduce rigidity, it is at least a candidate for the action site of VPA. But there is no direct evidence for this matter. The exact action site of VPA remains to be elucidated.

Aged↗

PubMed1997

Topographical analysis of cortical neuronal loss associated with disseminated selective neuronal necrosis and infarction after repeated ischemia.

A study was carried out of the distribution and density of the neurons remaining in the gerbil cerebral cortex following two 10-min periods of ischemia at either 3-, 5- or 48-h intervals. As the interval between the periods of ischemia increased, the ischemic injury was reduced from severe to milder infarction, and further from more to less intense disseminated selective neuronal necrosis. This model is suitable for studying the mechanisms of transition from selective neuronal necrosis to infarction at the threshold level of infarction.

Animals↗

PubMed1997

Long tract degeneration in familial sudanophilic leukodystrophy with prominent spheroids.

We describe a family with an autosomal dominant neurodegenerative disorder, three siblings of which were verified by autopsy as having sudanophilic leukodystrophy (SLD). The clinical picture of the family is one of progressive dementia and spastic paralysis. Pathological examinations detected diffuse and patchy white matter lesions and the widespread presence of axonal spheroids in the lesions of all three autopsy patients. Because change was found selectively in the pyramidal tracts and optic radiations, this disease is considered to affect the long tracts systematically. The SLD in the family we studied is distinguished from other leukodystrophies by its clinical and pathological features, indicative that it may be a special type of SLD.

Adolescent↗

PubMed1997

Systemic lupus erythematosus with multiple perivascular spongy changes in the cerebral deep structures, midbrain and cerebellar white matter: a case report.

A 42-year-old woman with systemic lupus erythematosus developed an episode of tonic seizures and progressive disturbance of consciousness at the terminal stage. Neuropathological examination of the brain revealed a nearly symmetrical distribution of multiple spongy foci in the internal capsules, thalami, globus pallidus, mesencephalic tegmentum, cerebral peduncles and hilus of the dentate nuclei. The spongy lesions were obviously distributed along apparently intact medium-sized veins, and contained large numbers of macrophages, and axonal spheroids and a few reactive astrocytes, without inflammatory cell infiltration. In addition, the perivenous spongy lesions exhibited IgG immunoreactivity, so it is surmised that some neurotoxic factor(s) that exuded from the veins in the center of the perivenous lesions may have brought about such a unique pathology.

Adult↗

PubMed1997

Acinar-islet cell carcinoma presenting as insulinoma.

A case of acinar-islet cell carcinoma presenting as insulinoma is reported. The patient was a 28-year-old man who presented with two convulsive episodes. Fajans' index [immunoreactive insulin (IRI; microU/ml/ glucose mg/dl)] and Turner's [IRI (microU/ml) x 100/glucose (mg/dl) - 30] index were high (2.8 and 308, respectively), as were serum proinsulin levels (550 pg/ml). Abdominal computed tomography and angiography revealed a highly vascular tumor in the pancreatic tail and several similar tumors in the liver. Histologic features of a biopsy specimen from a hepatic tumor were those of a malignant pancreatic endocrine tumor. Insulin secretion by the liver metastases was confirmed by venous sampling after arterial stimulation with calcium. These findings led us to diagnose malignant insulinoma with liver metastases. Serum levels of alpha-fetoprotein and trypsin were markedly elevated, to 2234 ng/ml (normal < 10) and 22,000 ng/ml (normal < 460) respectively, and these levels continued to rise with further growth of the liver metastases. Immunohistochemically, the metastatic liver tumor specimen was positive for alpha-fetoprotein, alpha 1-antichymotrypsin, chromogranin A, and neuron-specific enolase. These findings of amphicrine features in the tumor were indicative of acinar-islet cell carcinoma that produced alpha-fetoprotein and trypsin in addition to insulin.

Adenoma, Islet Cell↗

PubMed1997

Necrotizing Bacillus cereus infection of the meninges without inflammatory reaction in a patient with acute myelogenous leukemia: a case report.

A 64-year-old man in a severely immunocompromised state due to acute myelogenous leukemia died, respirator-unaided, about 10 h after the abrupt onset of coma. An earlier blood culture had yielded Bacillus cereus. The autopsy, performed 2 h after death, demonstrated diffuse subarachnoid hemorrhage without berry aneurysms, and the formalin-fixed brain was tinged with gray-brownish discoloration. The sections of the brain presented a whitish tint of the surface layer of all portion of the cerebral cortices, even those in the sulci. Histological examination of the brain revealed leptomeningeal B. cereus dissemination, and widespread necrosis of the leptomeninges and arachnoid vessels without inflammatory cell reaction. The grossly recognizable whitish surface layer of the cerebral cortex showed overt hyperchromatism, and contained neurons more degenerative than those located in the deeper cortical layer. The total absence of inflammatory reaction may be explained by a combination of the immunocompromised state of the patient and the character of B. cereus infection, which in itself induces little inflammatory reaction. The prominent lesions were confined to the cerebral surface layer and leptomeningeal tissue including the arachnoid vessels, which were all bathed in the cerebrospinal fluid, suggesting that some necrotizing toxins had been secreted into the fluid by the B. cereus. The necrosis of arachnoid vessels is thought to have in turn caused diffuse subarachnoid hemorrhage and marked disturbance of the cerebral blood flow, resulting in the terminal coma.

Bacillus cereus↗

PubMed1997

DNA vaccination for the induction of immune responses against hepatitis C virus proteins.

Recent analysis of clinical and experimental cases of hepatitis C virus (HCV) infection suggest the possible role of the viral nucléocapsid (C), the nonstructural protein 3 (NS3) and the envelope glycoproteins E1 and/or E2 in the mounting of immune responses capable to control infection (Botarelli et al., Gastroenterology, 1993, 104, 580-587; Choo et al., Proc. Natl Acad. Sci. USA, 1994, 91, 1294-1298). We have used DNA-based immunization to study the immune responses that can be induced by injecting DNA-derived immunogens encoding C and E2 sequences. Comparative analysis were performed in mice using expression plasmids containing full-length or partial gene sequences cloned in fusion with the hepatitis B virus surface antigen (HBV-HCV chimeras). The results obtained indicate that: (1) anti-C and anti-E2 antibodies can be induced with all constructs including the HBV-HCV chimeras; (2) titers range from 1:100 to 1:100000 depending on the antigen and nucleotide sequence context; (3) all HCV DNA immunogens are associated with a predominant Th1 response; (4) CTL can be detected against both HCV and HBV determinants.

Animals↗

PubMed1997

Autoimmune pancreatitis as a new clinical entity. Three cases of autoimmune pancreatitis with effective steroid therapy.

The most common forms of chronic pancreatitis are related to alcohol ingestion, whereas the entity of non-alcohol-associated (idiopathic) pancreatitis is poorly understood. Autoimmunity has been suggested as a possible etiologic factor of idiopathic chronic pancreatitis. A total of 362 Japanese patients underwent endoscopic retrograde pancreatography (ERP) for suspected pancreatic disease, and 161 were diagnosed with chronic pancreatitis. Among them, we found three cases (1.86% incidence) of unique chronic pancreatitis, in which ERP revealed diffuse narrowing of the main pancreatic duct with an irregular wall. We diagnosed these three patients as having pancreatitis associated with an autoimmune mechanism morphologically and biochemically and started them on steroid therapy. The characteristics of the these three patients were as follows: hypergammaglobulinemia, eosinophilia, ultrasonography showing hypoehoic diffuse swelling in the pancreas (sausage-like appearance), ERP showing diffuse narrowing of the main pancreatic duct with irregular like thumbprint-like marks, reversible exocrine insufficiency, and positive anti-carbonic anhydrase II antibody. After one month of the treatment with steroids, pancreatitis dramatically improved morphologically and enzymatically. Here we describe these cases of the suspected autoimmune chronic pancreatitis. We must recognize the concept and the features of autoimmune pancreatitis in order to avoid unnecessary surgery as pancreatic cancer.

Aged↗