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Biomedical subjects

M Matsuda

Publications and source records attributed to M Matsuda.

At least 271 records · Page 15Linked to original sources
PubMed1999

Cervical cord compression caused by a pillow in a postlaminectomy patient undergoing magnetic resonance imaging. Case report.

A 66-year-old man, who had undergone osteoplastic laminectomy for posttraumatic cervical myelopathy, underwent a second operation in which the replaced laminae were removed because of postoperative deep wound infection. Follow-up dynamic magnetic resonance imaging with flexion and extension views of the neck 1 year postsurgery demonstrated that the cervical cord was markedly compressed from behind in the extended position, although a wide subarachnoid space was observed in this region when the neck was in the flexed position. The cause of cord compression was the pillow that was placed underneath the patient's neck for maintaining the extended position, not the neck extension itself. This finding indicates that care must be taken during neuroradiological examination not to place a pillow under the neck of a patient who has undergone laminectomy. Nuchal compression could lead to cervical cord injury after laminectomy. Laminoplasty benefits the patient by protecting the cervical cord from secondary injury.

Aged↗
PubMed1999

[Anterior screw fixation combined with posterior interlaminar fusion for fracture of axis: report of two cases].

Two cases of axis fracture are reported. Traffic accidents were the cause of injury in both cases. The odontoid process was dislocated anterolaterally with fracture of the lateral mass of the axis in both cases. In Case 1 good alignment of the atlas and axis could not be maintained even with a Halo-vest. The case 2 patient with spinal cord compression caused by dislocation of the axis was referred to our hospital 8 weeks after the accident. Both cases were surgically treated in a similar fashion. Because of the lateral mass fracture and lateral displacement of the atlas relative to the axis, posterior screw fixation with interlaminar fixation (Magerl) was thought to carry a risk of causing damage to the vertebral artery. Because of this, anterior screw fixation combined with posterior wiring was conducted. First, the odontoid process was fixed anteriorly by a screw because it was able to be placed back in good alignment while the patient was in the supine position. Then, the posterior C1-2 interlaminar wiring with iliac bone graft was added. Rigid fixation was obtained without any complication. Various kinds of fixation, such as posterior interlaminar wiring, odontoid screw fixation and Magerl's fixation, have been reported for the treatment of unstable axis fracture. Among them Magerl's method has been regarded as the most stable. When it is not applicable, combination of the first two methods can be an alternative way of treatment for this odontoid process fracture.

Accidents, Traffic↗
PubMed1999

[Quantification of cerebral blood flow using 123I-IMP SPECT--a new method of estimating the input function from brain dynamic data].

In order to avoid continuous arterial blood sampling, we estimated input function by the method in that the whole brain time activity curves were fitted by two-term exponential function and differentiated analytically after the injection of N-isopropyl-p-[123I]iodoamphetamine (123I-IMP). This method was applied to 4 patients with cerebral infarction and 2 patients with brain tumor. Values of regional cerebral blood flow (rCBF) were calculated from the input function calibrated by one-point arterial sampling at 5 minutes after the injection using microsphere method, and then were compared with those obtained from the table-lookup method. In this study, we used the individual input function for the table-lookup method instead of the standard input function. The overall accuracy errors between two-term exponential functions and the whole brain time-activity curves were about 1%. The values of rCBF calculated by this method were well correlated with those by the table-lookup method (r = 0.901, p < 0.001). Optimal calibration time for this method was between 3-minute and 10-minute after 123I-IMP injection and the deviation of the rCBF values obtained by this method from those obtained by the table-lookup method in which the input function was calibrated at 5 minutes remained within 10%. This method is a less invasive and convenient alternative to the conventional methods which require continuous arterial blood sampling.

Adult↗
PubMed1999

[A case report of organic solvent abuse with amotivational syndrome].

We investigated an organic solvent abuser who developed amotivational syndrome employing neuropsychological examination (Rorschach test, Bender Gestalt test and Benton visual retention test), electroencephalography, magnetic resonance imaging (MRI) and single photon emission computed tomography (SPECT). The patient manifested a disability to maintain a goal-orient mental activity, immature reality testing and poor set shifting, which suggest frontal lobe dysfunction, as we have reported before in neuropsychological examination. In this case, single photon emission computed tomography (SPECT) also revealed a decrease of regional cerebral blood flow (rCBF) in the medial frontal lobe. These results may suggest a contribution of frontal lobe (especially medial frontal lobe) dysfunction to the pathogenesis of amotivational syndrome due to organic solvent abuse.

Adult↗
PubMed1999

[Intracerebral hemorrhage associated with long-lasting deficiency of factor XIII].

A 5-year-old boy had an intracerebral hematoma evacuated from the left parieto-occipital region at a local hospital. There was a difficulty in hemostasis during the operation. Postoperatively his neurological state gradually deteriorated. CT scans showed a gradual increase in intracerebral hemorrhage at the operated site. He was transferred to our clinic for further treatment. The preoperative blood coagulation profile showed that the activity of factor XIII was only 4%. The hematoma was removed without any trouble under administration of factor XIII. Postoperative course was also uneventful although the plasma level of factor XIII did not go up higher than 26% in spite of its daily administration. Although factor XIII administration was terminated one month after cranioplasty, the patient showed good recovery and the level of factor XIII spontaneously normalized in 6 months. The cause of the extremely low level of factor XIII in this case is not known, but it could be ascribed to massive hemorrhage.

Cerebral Hemorrhage↗
PubMed1999

A new type of Ser substitution for gamma Arg-275 in fibrinogen Kamogawa I characterized by impaired fibrin assembly.

A new type of substitution, Arg to Ser at gamma275, has been found in a heterozygous dysfibrinogen derived from a 23-year-old woman with no major bleeding or thrombosis. By sequence analyses of the affected gamma-chain and its gene. we found a single amino acid substitution of gamma Arg-275 to Ser in an aberrant gamma (274-302) residue peptide isolated from lysyl endopeptidase-digests of the patient's fibrinogen. In agreement with this amino acid substitution, we identified a single nucleotide exchange of A for C at position 5728 in the gamma-chain gene creating a codon (AGC) encoding Ser instead of the codon (CGC) encoding Arg at position gamma 275. Like two other known types of mutants with a His or Cys substitution at this position, the functional abnormality was characterized by delayed fibrin polymerization, most likely due to impaired abutting of two D domains of adjacent fibrin monomers in the same strand of fibrin protofibrils. The structural derangement that affects the D:D association may not be so severe as compared with those of Cys and His mutants, possessing an additional disulfide-linked Cys molecule and an imidazole ring at the mutation site, respectively.

Adult↗
PubMed1999

Atypical Rathke's cleft cyst associated with ossification.

We report a case of symptomatic Rathke's cleft cyst with ossification. CT scans showed curvilinear calcification on the wall of the cyst. MR images revealed a cystic sellar lesion with a nodular solid mass extending to the floor of the third ventricle. This case shows that calcification of the suprasellar cyst does not always suggest craniopharyngioma. Rathke's cysts should be histologically differentiated from craniopharyngiomas because their treatments are different.

Adult↗
PubMed1999

[Clinical roles of vitamins in hematopoietic disorders].

Vitamins are essential organisms which promote various metabolisms and physiological systems. Several vitamins play important roles in hematopoietic system. Vitamin B12, C and folic acid are associated with DNA synthesis of erythroid nucleus, the deficiency of which causes the megaloblastic anemia. Some megaloblatic anemia and sideroblastic anemia might response to vitamin B1 and B6, respectively. Vitamin K participates in some coagulation factors in coagulation-fibrinogenolysis system. It has been reported that vitamins A, D and K potentially differentiate leukemic cells and then induce the apoptosis, suggesting that they would be new therapeutic agents in acute leukemia.

Anemia↗
PubMed1999

[Successful endocrine chemotherapy in patients with multiple bone metastases of breast cancer--a case report].

A 54-year-old woman was admitted to our hospital with upper and lower back pain. She had previously developed multiple bone metastases of advanced breast cancer. Endocrine chemotherapy of tamoxifen citrate (TAM) 20 mg/day and carmofur (HCFU) 300 mg/day was started. Subsequently, medroxyprogesterone acetate (MPA) 600 mg/day and 5'-deoxy-5-fluorouridine (5'-DFUR) 600 mg/day were administered. In evaluating the treatment effect for symptomatic relief, partial response and performance status were judged to have improved from 4 to 2. At present, the patient is able to walk on her own to the hospital. She has lived 4 years with no newly developed lesions, and no adverse effects such as diarrhea or body weight gain have been observed. Substantial results can be achieved in patients with bone metastasis of breast cancer even with mild endocrine chemotherapy. A combination of radiotherapy, pain control, and orthopedic surgery suitable to each case is thought to be necessary.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1999

[Functional MRI of the human brain responses to olfactory stimulation].

Image artifacts such as signal loss or distortion due to intravoxel phase dispersion at the skull base are problematic in analysis by functional MRI (fMRI). Since the olfactory center of the brain is located in the medial temporal and basal frontal areas, it is a challenge to try to detect the Blood Oxygenation Level Dependent (BOLD) effect during fMRI at olfactory stimulation. We examined 20 normal volunteers with a 1.5-T MR system, employing multishot, interleaved echo-planar imaging (EPI). Olfactory stimulation was performed with 2-methyl-1, 3-cyclo-pentanedione, a caramel-like fragrance, by presenting it for 20 seconds with two cycles of rest-stimulus paradigm. Sites of functional activation were identified by correlation analysis with a threshold of p < 0.01. Most commonly activated areas were the orbitofrontal and primary olfactory cortices. Mild activation was also observed in the cingulate gyrus, lateral temporal cortex, cerebellum, parietal and occipital lobes. These results indicate that olfactory stimulation participates in the emotion and behavior processes. Interestingly, broad activation in the "silent" area of the frontal and temporal lobe was also observed in some cases. Multishot EPI was a useful method to evaluate brain activation at the basal level on fMRI.

Adult↗
PubMed1999

[Mental and physical symptoms in alcoholics after alcohol withdrawal--comparing with involutional melancholia patients].

As a factor of recurrence of drinking in patients with alcoholic dependence, emotional disorders accompanied by alcohol dependence has been noted in many reports. Particularly, it is noted to be very likely that depression after abstinence is an incentive to re-start drinking. In this study, we investigated depressive feeling in aspects of psychiatric and physical subjective symptoms after abstinence in patients with alcohol dependence, and compared the symptoms with those in patients with involutional depression. On analysis of the major component of psychiatric subjective symptoms, a sense of alienation, emotional instability, anxiety, and aggressiveness were observed. In involutional depression, depressive feeling, somnipathy, anxiety, self accusation/sense of guilt, delusion of culpability were observed. On analysis of the major component of physical subjective symptoms, autonomic nervous symptoms accompanied by feebleness, hysterical neurosis-like autonomic nervous symptoms, reduced sexual libido, anorexia, hydrodipsia/sweating were observed. Similarly, in patients with involutional depression, hysterical neurosis-like autonomic nervous symptoms, anorexia, elevation of tonus, general malaise, and hydrodipsia were noted. Differences in status were emphasized in comparison between the two groups in both analyses. Unlike involutional depression that exhibits the current features of depression, patients with alcohol dependence showed a sense of alienation, emotional instability, anxiety, and aggressiveness, reflecting self-uncertainty and loss of self-respect. Drinking may be re-started to relieve or reduce tension and frustration in such conditions.

Alcoholism↗
PubMed1999

[A case of non-Hodgkin lymphoma in the central nervous system, developing during treatment of galactorrhea amenorrhea syndrome].

We report a 27-year-old woman with a non-Hodgkin lymphoma in the central nervous system (CNS), showing monoparesis of the right upper extremity during treatment for the galactorrhea amenorrhea syndrome. The MRI demonstrated an infiltrative lesion with an obvious gadolinium-enhancement effect, extending from the pituitary stalk and hypothalamus through the 4th ventricle to the dorsal part of the medulla and upper cervical spinal cord. Because no tumors were detected in any other organ in either a physical examination or radiological investigations, including CT for the chest and abdomen, she was diagnosed as having primary CNS non-Hodgkin lymphoma (B cell origin) on the basis of an open brain biopsy. After the irradiation of the whole brain, followed by chemotherapy (methotrexate + CHOP), the infiltrative tumor disappeared on the MRI with a slight improvement for monoparesis of the right upper extremity. In this patient, primary CNS lymphoma might originate around the hypothalamus and infiltrate the medulla, inducing not only monoparesis of the right upper extremity but the galactorrhea amenorrhea syndrome.

Adult↗
PubMed1998

The adaptor protein Crk connects multiple cellular stimuli to the JNK signaling pathway.

c-Jun N-terminal kinases (JNKs) are potently activated by a number of cellular stimuli. Small GTPases, in particular Rac, are responsible for initiating the activation of the JNK pathways. So far, the signals leading from extracellular stimuli to the activation of Rac have remained elusive. Recent studies have demonstrated that the Src homology 2 (SH2)- and Src homology 3 (SH3)-containing adaptor protein Crk is capable of activating JNK when ectopically expressed. We found here that transient expression of Crk induces JNK activation, and this activation was dependent on both the SH2- and SH3-domains of Crk. Expression of p130(Cas) (Cas), a major binding protein for the Crk SH2-domain, also induced JNK activation, which was blocked by the SH2-mutant of Crk. JNK activation by Cas and Crk was effectively blocked by a dominant-negative form of Rac, suggesting for a linear pathway from the Cas-Crk-complex to the Rac-JNK activation. Many of the stimuli that activate the Rac-JNK pathway enhance engagement of the Crk SH2-domain. JNK activation by these stimuli, such as epidermal growth factor, integrin ligand binding and v-Src, was efficiently blocked by dominant-negative mutants of Crk. A dominant-negative form of Cas in turn blocked the integrin-, but not epidermal growth factor - nor v-Src-mediated JNK activation. Together, these results demonstrate an important role for Crk in connecting multiple cellular stimuli to the Rac-JNK pathway, and a role for the Cas-Crk complex in integrin-mediated JNK activation.

Adaptor Proteins, Signal Transducing↗
PubMed1998

A family of cAMP-binding proteins that directly activate Rap1.

cAMP (3',5' cyclic adenosine monophosphate) is a second messenger that in eukaryotic cells induces physiological responses ranging from growth, differentiation, and gene expression to secretion and neurotransmission. Most of these effects have been attributed to the binding of cAMP to cAMP-dependent protein kinase A (PKA). Here, a family of cAMP-binding proteins that are differentially distributed in the mammalian brain and body organs and that exhibit both cAMP-binding and guanine nucleotide exchange factor (GEF) domains is reported. These cAMP-regulated GEFs (cAMP-GEFs) bind cAMP and selectively activate the Ras superfamily guanine nucleotide binding protein Rap1A in a cAMP-dependent but PKA-independent manner. Our findings suggest the need to reformulate concepts of cAMP-mediated signaling to include direct coupling to Ras superfamily signaling.

1-Methyl-3-isobutylxanthine↗