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Biomedical subjects

Satoru Shimizu

Publications and source records attributed to Satoru Shimizu.

At least 37 records · Page 2Linked to original sources

[Advances in breast cancer chemotherapy].

Progress in chemotherapy for breast cancer was reviewed in the management of primary and metastatic diseases. In the metastatic setting, a survival advantage from combinations of drugs has not been proved over single agents given in sequence. Currently, active agents include anthracyclines, taxanes, vinorelbine, and fluoropyrimidines. Prospective randomized trials demonstrated that adjuvant systemic chemotherapy reduced annual odds of recurrence and death with combination therapy, regardless of age, stage, nodel status and hormone receptor status. One of the recent important questions in the adjuvant setting is the role of taxanes. Although many adjuvant taxane studies are still on going, 4 cycles of anthracycline-containing regimen sequenced with 4 cycles of a taxane appear to be the most beneficial treatment for advanced disease. Controversies and future directions are the high cost of treatment and the prediction of response to each drug for individual patients.

Anthracyclines↗

MacCarty keyhole and inferior orbital fissure in orbitozygomatic craniotomy.

OBJECTIVE: This study had two objectives. The first was to define the ideal position of the MacCarty keyhole, a commonly used craniotomy entry site into which three of the bone cuts in orbitozygomatic craniotomy extend. The second objective was to examine the relationships in the inferior orbital fissure, a site into which two of the bone cuts in orbitozygomatic craniotomy extend. METHODS: Twenty frontotemporal regions from adult skulls were examined to delineate the relationships between the surface anatomy of the fronto-orbitozygomatic region and the underlying frontal fossa and orbit. Drill holes placed along, above, and below the frontosphenoid suture were made beginning anteriorly at an area referred to as the three-suture junction, located at the junction of the frontozygomatic, sphenozygomatic, and frontosphenoid sutures. The site of the deep end of each hole was recorded to clarify the ideal position of the keyhole. The relationships in the inferior orbital fissure, the site of the lower end of the bone cut that begins in the orbital portion of the keyhole and extends along the lateral orbital wall, were also examined. CONCLUSION: Placing the MacCarty keyhole on the frontosphenoid suture 5 to 6 mm behind the three-suture junction results in greater preservation of the lateral wall and roof of the orbit than when the hole is placed at a more anterior site, as previously recommended. The anterolateral part of the inferior orbital fissure, which faces the temporal fossa and into which the bone cuts in the orbitozygomatic craniotomy extend, has a lower density of vascular and neural structures than the middle and posteromedial parts, which are related to the infratemporal and pterygopalatine fossa.

Cadaver↗

Rapid differential diagnosis of Graves' disease and painless thyroiditis using total T3/T4 ratio, TSH, and total alkaline phosphatase activity.

When thyrotoxic patients are first seen in an outpatient clinic, it is important to make a differential diagnosis of Graves' disease (GD) and painless thyroiditis (PT). Using the three parameters of total T3/T4 ratio, TSH and T-ALP activity, all of which can be obtained within one hour in our hospital, 173 untreated patients with thyrotoxicosis were evaluated for the ratio of each parameter. For GD vs. PT, total T3/T4 (ng/microg) ratio (>20), TSH (<0.005 microU/ml) and elevated T-ALP had a likelihood ratio of 2.14, 2.12 and 4.07, respectively. When a patient had all three positive parameters, the likelihood ratio increased to 5.81, which showed effective synergy. These data suggest that, in addition to total T3/T4 ratio and TSH value, T-ALP activity is a useful parameter for the rapid differentiation of GD. The lower T-ALP activity seen in PT is probably due to the fact that patients develop less severe thyrotoxicosis or visit hospital earlier than patients with GD. Therefore, the diagnostic accuracy for Graves' disease might be increased by using the three parameters in combination.

Adult↗

Hemifacial spasm following a blow to the mandible causing blunt injury to the peripheral facial nerve.

A 40-year-old male presented with hemifacial spasm manifesting as paroxysmal spontaneous twitches in the left peribuccal region persisting for 3 months. The symptoms began 7 days after an accident, when a signboard hit his left mandibular angle. Physical examination showed no trauma-related change in his face, and no neurological abnormality except for the twitches. Magnetic resonance imaging also showed no abnormalities of the facial nerve and adjacent regions. Electrophysiological studies showed synkinesis, so hemifacial spasm caused by peripheral facial nerve injury was suspect- ed. The symptoms subsided 4 months after the injury. Blunt injury to the facial nerve branches might cause hemifacial spasm.

Adult↗

Dilation of spinal epidural veins caused by spontaneous intracranial hypotension: case report.

A 30-year-old woman presented with headache which occurred when standing up from a recumbent position. Magnetic resonance (MR) imaging of the brain revealed slightly diffuse enhancement of the dura mater and two ventral extradural spinal flow voids in the supine position. Radionuclide cisternography identified cerebrospinal fluid leakage localized below the cervical level. Vertebral angiography demonstrated two dilated ventral extradural veins. The patient was treated by conservative therapy and improved with rest. The unusual clinical presentation with dilation of two epidural veins indicates the diagnostic value of MR imaging in cases of spontaneous intracranial hypotension.

Adult↗

Intractable seizures associated with proximal migration of a ventriculoperitoneal shunt. Case report.

A 6-year-old girl, who had received a ventriculoperitoneal (VP) shunt using the Codman-Hakim programmable valve system at age 3 months, presented with intractable seizures. Neuroimaging studies showed migration of the proximal part of the system, including the prechamber, into the cranium through the right frontal burr hole. Electroencephalography showed spike-and-wave complexes in the right hemisphere including the site of the migration. The ictus was resolved following revision surgery. The clinical findings suggested the seizures were due to irritation of the brain parenchyma by the migrated system. Proximal migration of a VP shunt may cause both shunt failure and additional focal symptoms.

Female↗

Obstruction of a Codman-Hakim programmable valve by a migrating pressure control cam.

Although the Codman-Hakim programmable valve is popular, several problems arising from its design have been described. The authors report an additional cause of shunt obstruction in the system. A 6-year-old girl who had received a ventriculoperitoneal shunt with the Codman-Hakim programmable valve system presented with worsening consciousness. The valve proved hard to flush, and emergency revision of the valve was performed. Examination of the extracted valve revealed that the pressure control cam had migrated into the outlet of the valve, thus causing the obstruction. A crack in the plastic housing surrounding the cam suggesting a past impact to the system was also revealed. These factors should thus be kept in mind as potential sources of obstruction of the valve system, especially in patients susceptible to episodes of head impact.

Child↗

Origins of the segmental arteries in the aorta: an anatomic study for selective catheterization with spinal arteriography.

BACKGROUND AND PURPOSE: The segmental arteries, which include the posterior intercostal, subcostal, and lumbar arteries, are gateways for performance of selective spinal arteriography of the thoracolumbar level. We performed a cadaveric study to clarify the anatomic relationship between the origins of the segmental arteries in the aorta and the vertebral column. METHODS: Five adult cadaveric aortas with intact thoracolumbar spines were dissected under magnification. In each specimen, nine pairs of posterior intercostal arteries, one pair of subcostal arteries, and four pairs of lumbar arteries were examined in detail. RESULTS: The origin of the posterior intercostal arteries in the upper thoracic level was situated at most about two levels caudal to the feeding level, whereas the origins in the lower levels were just caudal to the corresponding levels. The position of the bilateral orifices of the segmental arteries in the axial plane of the aorta was on the medial side at the thoracic levels, whereas it was on the dorsal side at the lumbar level. The horizontal distance between the orifices in the lumen of aorta was found to be wider at the thoracic level than the lumbar level, and the longitudinal distance was higher at the lower level, corresponding to the height of the vertebra. CONCLUSION: Understanding the 3D relationship of the initial segment of the segmental arteries with reference to the aorta and vertebral column is necessary for performance of the selective spinal arteriographic examination rationally by using a two-dimensional fluorescent display.

Adult↗

[Aplasia of the right internal carotid artery presenting with callosal hemorrhage: case report and review of the literature].

A 73-year-old woman without a history of cerebral ischemia suffered from sudden onset headache. Brain computed tomography (CT) showed intracerebral hemorrhage in the corpus callosum with intraventricular hemorrhage and thin subarachnoid hemorrhage in the basal cistern. Cerebral angiography showed narrowing of the right internal carotid artery just distal to its origin in the neck and abrupt occlusion just after branching of the ophthalmic artery with moyamoya-like vessels. The right A2 segment showed irregular dilatation and stenosis. The right middle cerebral artery was supplied from the basilar artery via the right posterior communicating artery. There was neither aneurysm nor arteriovenous malformation. Thin-slice bone-window CT of the skull base revealed hypoplasia of the right carotid canal. Aplasia of the right internal carotid artery was diagnosed. The origin of the hemorrhage was thought to be the irregularly opacified right A2 segment, which had been subjected to long-standing hemodynamic stress as collateral vessel.

Aged↗

[Questionnaire survey for doctors in the area of cooporation efforts when a terminal cancer is transformed to home medical care].

In order to smoothly transform a terminal cancer patient from hospital to home medical care, we surveyed based on questionnaires to examine doctor's roles of each primary and regional hospitals and its cooperation among the hospitals. We established two types of questionnaires for two groups, a primary doctor group and a regional doctor group, and distributed and collected them. A total of 123 doctors (35 primary doctors and 88 regional doctors) responded out of 185 doctors, and the collection rate was 66.5%. The survey result indicated that there were significant differences among the primary and regional doctors in evaluating patient's family members for understanding of the patients disease at the time of discharge, how to give a treatment to the patient, alleviating patient's disease conditions and a mental support given by doctor to family members from the hospital. Meanwhile, about 70% of regional doctors answered that family members had some sort of anxieties during a night and at the time of emergency to care the patient. It also revealed that about 70% of regional doctors had experienced troubles in coordinating with a primary hospital. On the other hand, 62% of primary doctors answered that they always provided necessary care to the patient at the time of emergency. In providing a safe and a high degree of QOL in home medical care settings, it is important to have specific common purposes among the two groups of doctors and patients. Furthermore, the primary and regional doctors have to be cooperative, specify duty roles when the patient is transformed to home medical care, and to have ways to accomplish mutual common goals for patients.

Caregivers↗

A multicenter phase II study of docetaxel 60 mg/m2 as first-line chemotherapy in patients with advanced or recurrent breast cancer.

PURPOSE: Docetaxel is an active agent as first-line chemotherapy in patients with advanced breast cancer at a dosage of 100 mg/m2. However, the efficacy of this agent as a first-line drug when used at a lower dosage is unclear. This study was performed to evaluate the clinical efficacy and safety of 60 mg/m2 docetaxel for the treatment of breast cancer. PATIENTS AND METHODS: This study enrolled 23 patients with advanced and/or metastatic breast cancer, who had not been treated with an anthracycline or taxane previously. Treatment with docetaxel was continued in patients showing a response until there was evidence of disease progression or unacceptable toxicity. RESULTS: Among 20 fully evaluated patients, the overall response rate was 50.0% and the median time to progression was 31 weeks. The most commonly observed adverse events were neutropenia (78.2%) and fatigue (60.9%). Fluid retention occurred in only 8.7% of the patients. Adverse events did not cause discontinuation of the treatment. CONCLUSION: Docetaxel achieved good disease control with mild adverse events in first-line treatment at a dosage of 60 mg/m2.

Adult↗

A phase II study of S-1 in patients with metastatic breast cancer--a Japanese trial by the S-1 Cooperative Study Group, Breast Cancer Working Group.

BACKGROUND: S-1 is a newly developed novel oral dihydrouracil dehydrogenase inhibiting fluoropyrimidine drug consisting of 1 M tegafur (FT), 0.4 M 5-chloro-2, 4-dihydroxypyrimidine (gimeracil), and 1 M potassium oxonate (oteracil), with efficient antitumor activity and low gastrointestinal toxicity which is widely used in Japan against advanced gastric, head and neck cancers. We investigated its clinical efficacy against metastatic breast cancer. METHODS: A non-blind phase II study was carried out to evaluate the efficacy and toxicity in metastatic breast cancer patients. Patients with measurable metastasis foci (n=111) were enrolled, and 108 patients were regarded as eligible. S-1 was administered orally at a standard dose of 80 mg/m2/day b.i.d. One course consisted of 28 consecutive days of administration followed by a 14-day rest, and courses were repeated up to six times. RESULTS: Among the eligible patients, 10 had a complete response and 35 had a partial response, with an overall response rate (CR+PR) of 41.7% (95% confidence interval: CI, 32.3-51.5%). The incidences of toxicity (> or =grade 3) were neutropenia 9.1%, anemia 0.9%, anorexia 3.6%, stomatitis 1.8%, nausea/vomiting 1.8%, diarrhea 0.9%, and fatigue 2.7%, however no treatment-related deaths were observed. The median survival time was 872 days (95% CI, 572-1,110 days). There was no difference in response rate or toxicity between the under 65-year-old group and the older group. CONCLUSION: S-1 was demonstrated to have high efficacy with low gastrointestinal toxicity even in older patients and will be a promising new chemotherapy drug for metastatic breast cancer.

Administration, Oral↗

Swimming exercise in infancy has beneficial effect on the hearts in cardiomyopathic Syrian hamsters.

The phenotypic expression of cardiomyopathy is greatly influenced by extrinsic factors other than intrinsic genetic defects, such as environmental stress. Exercise is assumed to be an important extrinsic factor, since sudden death is sometimes seen during exercise in young patients with hypertrophic cardiomyopathy (HCM). However, the long-term effects of mild exercise on phenotypic expression in cardiomyopathy remain unclear. To evaluate the effects of exercise performed during infancy or adolescence in cardiomyopathic patients, cardiomyopathic Syrian hamsters (BIO14.6) were subjected to swimming. BIO14.6 and age-matched congenic normal hamsters (CN) as controls were divided into three groups: sedentary (Sed), and trained during infancy (Inf) and during adolescence (Ado). Histological and biochemical analysis of 41-week-old hamsters revealed that (1) the relative level of beta-myosin heavy chain mRNA was significantly lower in the Inf group than in the Sed and Ado groups of BIO14.6. The level in the Inf group of BIO14.6 was compatible with that in the age-matched Sed group of the CN strain; (2) in BIO14.6, degenerative mitochondrial change in the cardiomyocytes was not seen in the Inf group while it was common in the Sed and Ado groups; (3) calcineurin phosphatase activity in the swimming group in 10-week-old CN was significantly higher than that of the age-matched sedentary group, and was as much as that of the swimming and sedentary groups in 10- and 41-week-old BIO14.6.

Age Factors↗

Crystal structure of d(CGAAGC); association of two parallel-stranded duplexes through anti-parallel-stranded duplex formation.

We reported that d(CGAA) prefers to form a parallel duplex with homo base pair formations. To survey a possibility of longer parallel duplex, crystal structure of d(CGAAGC) has been determined. As expected, the CGAA part of the hexamer forms a parallel duplex with the corresponding part of another hexamer. The remaining G and C residues of one strand are stacked on the end of the parallel duplex, while those of the other strand are flip out and extended to the outside. The stacked residues form an anti-parallel duplex with the extended residues of the adjacent parallel duplex to form a dimer between the two parallel duplexes.

Base Sequence↗

A cross-sectional analysis of quality of life in Japanese acne patients using the Japanese version of Skindex-16.

We measured the quality of life of Japanese patients with acne using the Japanese version of Skindex-16, a semantically equivalent and validated translation of the original version produced by Chren et al. A total of 210 acne patients were enrolled in this study. The results showed that patients with acne experienced more severe emotional effects from their skin disease than functional or symptomatic effects. The scores for emotional aspects were related to the severity of the patients' acne following a prescribed scale, but the scores were high even when the patients only had a few comedones. Akaike's information criterion showed that the scores for symptoms were related to the severity of the patients' acne, and the patients' emotions were related to the interval between clinic visits. To improve patients' quality of life, treatment of comedones should be fully respected. In addition, dermatologists should encourage patients to visit clinics regularly to help them improve the emotional aspects of their quality of life.

Acne Vulgaris↗

Functional characterization of a catabolic plasmid from polychlorinated- biphenyl-degrading Rhodococcus sp. strain RHA1.

Rhodococcus sp. strain RHA1, a potent polychlorinated-biphenyl (PCB)-degrading strain, contains three linear plasmids ranging in size from 330 to 1,100 kb. As part of a genome sequencing project, we report here the complete sequence and characterization of the smallest and least-well-characterized of the RHA1 plasmids, pRHL3. The plasmid is an actinomycete invertron, containing large terminal inverted repeats with a tightly associated protein and a predicted open reading frame (ORF) that is similar to that of a mycobacterial rep gene. The pRHL3 plasmid has 300 putative genes, almost 21% of which are predicted to have a catabolic function. Most of these are organized into three clusters. One of the catabolic clusters was predicted to include limonene degradation genes. Consistent with this prediction, RHA1 grew on limonene, carveol, or carvone as the sole carbon source. The plasmid carries three cytochrome P450-encoding (CYP) genes, a finding consistent with the high number of CYP genes found in other actinomycetes. Two of the CYP genes appear to belong to novel families; the third belongs to CYP family 116 but appears to belong to a novel class based on the predicted domain structure of its reductase. Analyses indicate that pRHL3 also contains four putative "genomic islands" (likely to have been acquired by horizontal transfer), insertion sequence elements, 19 transposase genes, and a duplication that spans two ORFs. One of the genomic islands appears to encode resistance to heavy metals. The plasmid does not appear to contain any housekeeping genes. However, each of the three catabolic clusters contains related genes that appear to be involved in glucose metabolism.

Amino Acid Sequence↗

Manual occipital ventricular puncture for cerebrospinal fluid shunt surgery: can aiming be standardized?

The manual occipital ventricular puncture is a standard surgical procedure, but specific targeting has not received sufficient attention despite the experience of anatomical disorientation. This study tried to identify an exact site for the ideal trajectory with this method, especially in the sagittal plane, which avoids contact with the choroid plexus that may be the major source of complications. A total of 44 consecutive adult cases undergoing cerebrospinal fluid shunting through the occipital route for hydrocephalus were retrospectively reviewed for the following: correlations between burr hole site, direction of puncture, and location of the ventricular catheter based on postsurgical radiological studies; calculation of the ideal trajectory to place the catheter tip in the anterior horn of the lateral ventricle without contact with the choroid plexus through the standard occipital burr hole. In addition, the relationships between the location of the ventricular structure, the cranial base line connecting the nasion and inion, and the size of the ventricle were evaluated. Incorrect catheter emplacement was found in five cases, which suggested that this procedure using the standard burr hole site and aim point might result in incorrect catheter placement. The ideal external aim points were widely distributed because of the variable heights of ventricular structures from the cranial baseline. No correlation between the locations of the anatomical points and ventricular size was found. The present study could not define a standard external aim point. Tailored preoperative planning of the trajectory is recommended.

Adolescent↗

[A late phase II clinical study of S-1 in patients with progressed, refractory breast cancer].

A late phase II clinical study of S-1 against advanced or refractory breast cancer was done by 37 institutes in Japan. S-1 was administered twice daily at 80, 100 or 120 mg/body/day consecutively for 28 days followed by 14 days of rest (1 course). Eighty-three patients were enrolled and 81 were eligible for the study. The response ratio was 42.0% with 6 CR and 28 PR and its 95% confidence interval for the response was 31.1 to 53.5%. The median survival period was 910 days (95% confidence interval was 493-1, 083 days). The observed major adverse reactions (> or = grade 2) were as follows: hematological toxicities: leukopenia 21.0% (17/81), neutropenia 28.4% (23/81), erythropenia 4.9% (4/81); gastrointestinal toxicities: anorexia 9.9% (8/81), nausea and vomiting 12.3% (10/81), diarrhea 8.6% (7/81), stomatitis 1.2% (1/81), and fatigue 8.6% (7/81). The severe adverse reactions (> or = grade 3) were as follows; hematological toxicities: neutropenia 8.6% (7/81), anorexia 4.9% (4/81), fatigue 3.7% (3/81), nausea and vomiting 1.2% (1/81), diarrhea 1.2% (1/81), stomatitis 1.2% (1/81). Grade 4 adverse reactions (neutropenia and fatigue) were observed only in 1 patient. The ratio without hospitalization was 87.7%. These results strongly suggest the superior efficacy and safety of S-1 against patients suffering from advanced, refractory breast cancer. Therefore, S-1 may be a new therapeutic agent to prolong the survival period of breast cancer patients due to its high antitumor activity and low toxicity.

Adult↗