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Biomedical subjects

Y Kida

Publications and source records attributed to Y Kida.

At least 37 records · Page 2Linked to original sources

Radiosurgery for bilateral neurinomas associated with neurofibromatosis type 2.

OBJECTIVE: The clinical course of bilateral acoustic tumors associated with neurofibromatosis (NF2) is generally troublesome, and no definite treatment strategy has been established. Follow-up results of bilateral acoustic tumors after radiosurgery are reported herein. METHODS: The current indications for radiosurgery are 1) a growing tumor less than 30 mm in mean diameter, 2) the ipsilateral ear has no serviceable hearing, and 3) there is risk of brain stem compression or brain stem dysfunction. Twenty cases of bilateral acoustic tumors were treated with the gamma knife, including 7 males and 13 females. The mean age was 38.2 years and the mean tumor size 24.4 mm. The tumors were treated with mean maximum and marginal doses of 26.8 Gy and 13.0 Gy, respectively. Among them, 12 patients had profound hearing loss in the ipsilateral (treated) ear, but the other 8 had serviceable hearing. RESULTS: Tumors treated with radiosurgery showed central necrosis in 60% of the cases at 6 months and in 70% at 9 months after radiosurgery. Thereafter, the tumors often demonstrated slow regression. The rate of tumor shrinkage was 20% at 12 months, 35% at 24 months, and almost 60% at 36 months. At the last follow-up (mean 33.6 months), the tumors demonstrated shrinkage in 50% and tumor control in 100%. The contralateral tumors were stable in 12 (60%) and enlarged in 8 (40%). Preservation of serviceable hearing ipsilaterally was obtained in 33.3%. Deterioration of ipsilateral facial nerve function, either in the natural course or as a complication, occurred in 10%. CONCLUSIONS: Because of good tumor control and tumor shrinkage as well as an acceptable complication rate, radiosurgery should be incorporated in the treatment strategy for bilateral acoustic tumors associated with NF2.

Adolescent↗

Seizure control after radiosurgery on cerebral arteriovenous malformations.

Among 462 cases of cerebral arteriovenous malformation (AVM) treated with gamma-radiosurgery, the initial presentations were haemorrhage in 68%, epilepsy in 12.8%, neurological deficits in 3.2%, minor symptoms in 7.6% and asymptomatic in 4.5% respectively. There were 79 cases (17.1%) who had had a convulsive seizure before radiosurgery and they were classified into two groups: 58 cases presented with seizure as an initial symptoms (group A) and the other 21 cases mostly had seizures following intracranial haemorrhage (group B). Before radiosurgery, generalised seizure was the predominant seizure pattern in both groups, followed by pure partial and complex partial seizures. There was no major difference in seizure patterns or seizure frequency in group A and B. At radiosurgery AVMs were treated with a mean maximum dose of 37.2 Gy and a marginal dose of 19.8 Gy. Seizures had apparently decreased in most of the cases at the last follow-up (mean 24 months) according to the obliteration of the nidus. Seizures were either decreased or had disappeared in 91.6% of group A and 62.5% of group B patients. The overall results indicate that seizures improved in 85.5%, were changed in 11.6% and deteriorated in 2.9% of patients. Radiosurgery is effective not only for the obliteration of nidus of cerebral AVM, but also for seizure control, even before complete occlusion of the nidus.

Adult↗

Embolisation of cerebral arteriovenous malformations to assure successful subsequent radiosurgery.

This study investigated the angiographic changes in embolised arteriovenous malformations (AVMs) pre- and post-embolisation and preradiosurgery to clarify the usefulness of embolisation as a pretreatment for radiosurgery and the strategy of embolisation for the radiosurgical success. A total of 37 patients with cerebral AVMs treated over a period of 4 years was investigated. All the AVMs were embolised with N-butyl cyanoacrylate and 2 months later they were treated by radiosurgery. The size of AVM nidus reduced just following the embolisation (mean 21.9 ml to 3.9 ml). The angiogram taken in preparation for radiosurgery showed a further size reduction in the nidus of 16 AVMs, no change in 10 and regrowth in 11. In all the cases where size was reduced, the nidus was densely packed, while all the regrown AVMs were of the diffuse type. Five AVMs disappeared following radiosurgery, all of which were size-reduction or no-change cases. In conclusion, to achieve success in subsequent radiosurgery, nidus embolisation and the occlusion of fistulous and meningeal feeders are mandatory. Imprudent proximal feeder occlusion and the use of embolic materials with a risk of recanalisation should be avoided to prevent regrowth of the nidus, which may lead to errors in planning the radiosurgery to follow.

Adolescent↗

Radiosurgery for epilepsy associated with cavernous malformation: retrospective study in 49 patients.

OBJECTIVE: Microsurgical resection of a cavernous malformation (CM) with or without associated cortical resection can provide efficient treatment of drug-resistant associated epilepsy. To explore the potential alternative role of radiosurgery and to evaluate its safety and efficacy for this indication, we conducted a retrospective multicenter study. METHODS: We retrospectively reviewed the files of patients with long-lasting drug-resistant epilepsy, presumably caused by CM, who were treated by gamma knife (GK) surgery for the control of their epilepsy in five centers (Marseilles, Komaki City, Prague, Graz, and Sheffield). A satisfactory follow-up was available for 49 patients (mean follow-up period, 23.66 +/- 13 mo). The mean duration of epilepsy before the GK procedure was 7.5 (+/-9.3) years. The mean frequency of seizures was 6.9/month (+/-14). The mean marginal radiation dose was 19.17 Gy +/- 4.4 (range, 11.25-36). Among the 49 patients, 17 (35%) had a CM located in or involving a highly functional area. RESULTS: At the last follow-up examination, 26 patients (53%) were seizure-free (Engel's Class I), including 24 in Class IA (49%) and 2 patients with occasional auras (Class IB, 4%). A highly significant decrease in the number of seizures was achieved in 10 patients (Class IIB, 20%). The remaining 13 patients (26%) showed little or no improvement. The mediotemporal site was associated with a higher risk of failure. One patient bled during the observation period, and another experienced radiation-induced edema with transient aphasia. Postradiosurgery excision was performed in five patients, and a second radiosurgical treatment was carried out in one patient. CONCLUSION: This series is the first to specifically evaluate the capability of GK surgery to safely and efficiently treat epilepsy associated with CM. Seizure control can be reached when a good electroclinical correlation exists between CM location and epileptogenic zone. Although we do not recommend GK surgery for prevention of bleeding for a CM that has not bled previously, our findings suggest that GK surgery can be proposed for the treatment of epilepsy when the CM is located in a highly functional area.

Adult↗

Gamma knife radiosurgery as a primary treatment for prolactinomas.

OBJECT: The purpose of this study was to estimate the efficacy of gamma knife radiosurgery (GKS) in controlling tumor growth and endocrinopathy associated with prolactinomas. METHODS: Between 1993 and 1997, 164 of 469 patients with pituitary adenomas treated by GKS harbored prolactinomas. The dose to the tumor margin ranged from 9 to 35 Gy (mean 31.2 Gy), and the visual pathways were exposed to a dose of less than 10 Gy. The mean tumor diameter was 13.4 mm. The mean follow-up time for 128 cases was 33.2 months (range 6-72 months). Tumor control was observed in all but two patients who underwent surgery 18 and 36 months, respectively, after GKS. Clinical cure was achieved in 67 cases. Clinical improvement was noted with a decrease in the hyperprolactinemia after GKS. Nonetheless, in 31 (29%) of 108 patients who were followed for more than 2 years no improvement in serum prolactin levels was demonstrated, although this could be normalized by bromocriptine administration after treatment. Nine infertile women became pregnant 2 to 13 months after GKS and all gave birth to normal children. There was no visual deterioration related to GKS. Five women experienced premature menopause. In these patients there was subtotal disappearance of the tumor and an empty sella developed. CONCLUSIONS: Gamma knife radiosurgery as a primary treatment for prolactinomas can be safe and effective both for controlling tumor growth and for normalization of prolactin hypersecretion. A higher margin dose (> or = 30 Gy) seemed to be associated with a better clinical outcome. Gamma knife radiosurgery may make prolactinomas more sensitive to the bromocriptine.

Humans↗

Glycogen storage disease type Ib: structural and mutational analysis of the microsomal glucose-6-phosphate transporter gene.

Glycogen storage disease type Ib is caused by a mutation in the gene encoding microsomal glucose-6-phosphate (G6P) transporter. We determined the exon/intron organization of the G6P transporter gene. Four overlapping genomic fragments containing the entire coding region of the gene were amplified by polymerase chain reaction (PCR) using exonic primers, and their nucleotide sequences were determined. The gene spans 4.5 kb and has eight exons. All exon/intron boundaries adhered to the canonical AG/GT rule. We then designed eight pairs of PCR primers to amplify all coding exons for a mutational analysis and studied five Japanese patients with the disease. Two novel homozygous mutations were identified in two families: a three-base deletion (delV235) in exon 2 in a consanguineous family and a splicing mutation (IVS7+1G-->T) in intron 7 in a nonconsanguineous family. Patient 3 was a compound heterozygote of W118R and IVS1+1G-->A, both of which we previously identified [Kure et al., 1998: Biochem Biophys Res Commun 248:426-431]. Patients 4 and 5 were homozygotes of W118R. Including our previous study, we found a total of ten W118R alleles in nine Japanese patients. The results support our previous suggestion that W118R is prevalent among Japanese patients. The genomic sequence data and mutation spectrum obtained from the Japanese patients will facilitate genetic diagnosis of glycogen storage disease type Ib.

Antiporters↗

K-ras point mutations in the supernatants of pancreatic juice and bile are reliable for diagnosis of pancreas and biliary tract carcinomas complementary to cytologic examination.

In order to clarify whether DNA analysis for K-ras mutation can be used to diagnose cancers in supernatants of pancreatic juice and bile, samples from 29 cases of pancreatic, biliary tract, gastric, and neuroendocrine carcinomas, 1 malignant lymphoma case, 2 cases of pancreatic adenoma, 9 cases of chronic pancreatitis and 21 other non-cancer cases were examined. Polymerase chain reaction (PCR) products for K-ras gene codons 2 to 97 of exons 1 and 2 were generated with 33/33 (100%) pancreatic juice and 41/41 (100%) bile samples. By the single strand conformation polymorphism (SSCP) method, point mutations were detected in the pancreatic juice or bile supernatants of 13/13 (100%) pancreas cancer cases, 5/14 (35.7%) biliary tract cancer cases, 1/2 (50.0%) pancreatic adenoma cases and 3/9 (33.3%) chronic pancreatitis cases. Direct sequencing confirmed identical point mutations in the supernatants, malignant cells of cytologic smears of pancreatic juice or bile and cancer tissues. The DNA analysis demonstrated the presence of K-ras point mutations in 3 cases of pancreatic carcinomas with false-negative cytologic diagnoses. This novel method allows simultaneous testing for genetic abnormalities in supernatants of pancreatic juice and bile, after removing cells for cytologic diagnosis and screening for pancreatic and biliary tract tumors.

Bile↗

Gamma Knife radiosurgery for epilepsy associated with cavernous hemangiomas: a retrospective study of 49 cases.

A retrospective multicenter study was performed to evaluate the effectiveness of Gamma Knife radiosurgery (GKRS) in the treatment of drug resistant epilepsy associated with cavernous hemangiomas (CH). The mean duration of epilepsy before GKRS was 7.5 ¿ 9.3 years. The mean frequency of seizures was 6.9 ¿ 14/month. The mean marginal dose was 19.2 ¿ 4.4 Gy (range 11.3 to 36 Gy). The mean follow up was 23.7 ¿ 13 months. At the most recent follow-up examination, 26 (53%) patients were seizure-free (Engel s class I) including 24 in class IA (49%) and two (4%) patients with occasional auras (class IB, 4%). A highly significant decrease in the number of seizures was achieved in 10 (20%) patients, which is class lIB. The remaining 13 (2.6%) patients showed little or no improvement. A medial temporal location was associated with a higher risk of failure. In contrast, all patients with central region CH were seizure free. Two severe but transient complications were observed. There was hemorrhage in one patient and another patient suffered from radio-induced edema with transient aphasia. This series is the first demonstrating that GKRS can be used safely and efficiently to treat epilepsy associated to CH. Seizure control can be reached when a good electro-clinical correlation exists between CH location and epileptogenic zone. Our findings suggest that GKRS can be used to treat epilepsy for CH located in highly functional areas, particularly the central region.

Adult↗

[Two cases of facial neurinoma successfully treated with gamma knife radiosurgery].

Two cases of facial neurinoma successfully treated with gamma knife radiosurgery are reported. Case 1, a 33-year-old female, developed a right-sided hemifacial spasm about five years ago. Then she suffered gradual progression of right-sided facial palsy, dysgeusia and reduction of lacrimation, but she had no hearing disturbance. T1-weighted MRI with gadolinium DTPA showed a well-circumscribed tumor at the geniculate ganglion extending to the middle cranial fossa. The tumor was treated with gamma knife radiosurgery which reduced its size, but didn't reduce the patient's facial palsy. Case 2, a 36-year-old female, presented with fluctuating facial palsy and sensorineural hearing loss lasting for fourteen years. T1-weighted enhanced MRI showed a well-enhanced tumor at the CP angle extending to the middle cranial fossa. The tumor was treated with gamma knife radiosurgery, which caused central tumor necrosis, but didn't reduce the tumor size. Meanwhile the patient's facial palsy improved. Gamma knife radiosurgery is apparently effective against facial neurinomas without producing serious complications such as complete facial palsy and hearing loss. Our study indicates that gamma knife radiosurgery is a useful therapeutic alternative for facial neurinomas.

Adult↗

Radiosurgery of angiographically occult vascular malformations.

Angiographically occult vascular lesions (AVOMs) are vascular lesions not visualized on standard cerebral angiography. The possibility of managing these difficult lesions with radiosurgery is discussed. The radiosurgical treatments and results of AVOMs are described and the strategies for managing AOVMs and cavernous malformations are discussed.

Adolescent↗

Membrane topology of NADPH-cytochrome P450 reductase on the endoplasmic reticulum.

Topology of the membrane-anchoring segment of mouse NADPH-cytochrome P450 reductase in the endoplasmic reticulum membrane was elucidated. An N-glycosylation site was generated in the amino-terminal hydrophilic sequence of the reductase, and the mutated protein was expressed in a cell-free system in the presence of microsomal vesicles. The in vitro synthesized reductase protein was integrated into the microsomal membrane and N-glycosylated depending on the presence of signal recognition particles. We conclude that the amino-terminal membrane-anchoring segment of the reductase is a type I signal-anchor sequence which shows amino-terminus-lumen and carboxy-terminus-cytoplasm topology.

Amino Acid Sequence↗

Three siblings of fatal infantile encephalopathy with olivopontocerebellar hypoplasia and microcephaly.

We report three male siblings born with fatal encephalopathy comprising microcephaly, myoclonus and muscle hypertonia. All three patients died during infancy. Postmortem examination on the brain revealed that all infants had neuronal loss in the cerebellar cortex, inferior olivary and pontine nuclei, which were more pronounced in the older subject than the younger ones. In addition, they were associated with polymicrogyria in the cerebral cortex of the insula, olivary and dentate nuclear dysplasia, and a hypoplastic corticospinal tract. The clinical and neuropathological findings in our cases were identical to those in fatal infantile encephalopathy with olivopontocerebellar hypoplasia and microencephaly [Albrecht et al., Acta Neuropathol 1993;85:394-399], but an association of malformations suggests a new genetic factor in pathogenesis of olivopontocerebellar hypoplasia.

Abnormalities, Multiple↗

HLA-DRB1 alleles contribute to determining the prognosis of Japanese diabetes mellitus positive for antibodies to glutamate decarboxylase.

Diabetes mellitus positive for antibodies to glutamate decarboxylase is heterogeneous as far as the degree of impairment of endogenous insulin release, though antibodies to glutamate decarboxylase are the most useful marker for future insulin deficiency. To investigate what determines the prognosis of diabetes mellitus positive for antibodies to glutamate decarboxylase, we measured HLA-DRB1 alleles in three groups: 77 cases of insulin-dependent diabetes mellitus (IDDM), 44 of non-insulin-dependent diabetes mellitus (NIDDM) with secondary failure of oral hypoglycemic therapy, and 22 of NIDDM well controlled by diet and/or sulfonylurea agents. The proportion of susceptible and resistant alleles to IDDM determined the degree of insulin deficiency, and comparison of IDDM to NIDDM well controlled by diet and/or sulfonylurea agents revealed significant differences in DRB1*0405 (P < 0.05; RR = 2.82 and RR = 0.89, respectively) and DRB1*1502 (P < 0.001; RR = 0.02 and RR = 2.19, respectively). This study revealed that HLA-DRB1 alleles contribute to determining the prognosis of Japanese diabetes mellitus positive for antibodies to glutamate decarboxylase.

Adolescent↗

A case of atypical chronic myeloid leukemia regarded as MDS with myeloproliferative features.

We report a case of atypical chronic myeloid leukemia (aCML) who showed marked neutrophilia without dysplastic features, basophilia or monocytosis. These findings diverged somewhat from the FAB criteria for aCML. The patient's erythroid cells and megakaryocytes were dysplastic. His marrow cells formed no spontaneous colonies, as shown by cell culture. The cells formed many small-sized neutrophil colonies with G-CSF stimulation. Interestingly, they formed mainly neutrophil colonies with GM-CSF stimulation. These findings were different from those of chronic myelomonocytic leukemia cells and chronic granulocytic leukemia cells. This aCML case showed the cytological features of myelodysplastic syndrome.

Humans↗

Treatment of the survivors from the Nagoya air crash.

Six patients were taken to our hospital alive just after the air crash at Nagoya Airport in 1994. On admission, all patients suffered from profound shock which rapidly progressed. Serum albumin and hemoglobin levels, and platelet count decreased on admission or soon after. The four patients who died could not recover from the shock and associated rapid deterioration of neurological signs. However, two patients were successfully treated with massive transfusion of packed red blood cells, fresh frozen plasma, fresh blood, and/or platelet concentrate and survived to discharge. We recommend addition of albumin to the transfusate in such cases.

Accidents, Aviation↗