Biomedical subjects

H Baba

Publications and source records attributed to H Baba.

At least 109 records · Page 6Linked to original sources

PubMed1999

Quantitative EEG analyses and surgical outcome after corpus callosotomy.

PURPOSE: To clarify the relation between quantitative electroencephalogram (EEG) findings and outcome following corpus callosotomy (CC). METHODS: The degree of bilateral synchrony and morphologic similarity of spike-wave discharges was analyzed by using a cross-correlation analysis and the measurements of amplitude differences between bilateral homologous regions in 22 patients who underwent anterior CCs for intractable symptomatic generalized epilepsies (SGE; 17 patients) and frontal lobe epilepsy (five patients). RESULTS: Interictal generalized synchronous spike-wave (GSSW) bursts in the SGE patients were disrupted and changed to unilateral spike-waves (USWs) in 11 patients and to bilaterally independent spike-waves (BISWs) in six. The USW group had better surgical outcome than the BISW group. Preoperatively, the USW group had significantly lower interhemispheric synchrony (IS) and fewer regional changes in the side leading in time and the side dominant for amplitude, suggesting unilaterally predominant epileptogenesis that triggered the secondary bilateral synchrony. Postoperatively, the BISW group had a more marked reduction in IS because of independent discharges from bilateral epileptogenic areas, and the USW group had a greater amplitude difference because of unilateralized spike-waves. In addition, an excellent surgical outcome was related to (a) the preoperative degree of the morphologic similarity of the bilateral spike-waves (only a small variation during a burst of spike-waves) and the few instances of regional changes in the side leading in time and in the side dominant for amplitude; and (b) to large postoperative amplitude differences. CONCLUSION: Preoperative quantitative EEG analyses enabled us to predict the underlying conditions of epileptogenesis and the surgical outcomes in patients undergoing CC.

Adolescent↗

PubMed1999

Recurrences and relation to tumor growth potential and local immune response in node-negative advanced gastric cancer.

Biological characteristics and the prognosis for subjects with node-negative advanced gastric cancer have been given little attention in related literature. We analyzed data on 112 patients with serosally invasive gastric cancer who were lymph node metastasis-negative; all had been surgically treated in the Department of Surgery II, Kyushu University Hospital, between 1970 and 1992. Recurrences and relation to the growth potential of the tumor and local immune response were examined. Thirty patients died with a recurrence of the gastric cancer, and in these patients, the tumor was larger, the whole stomach was more frequently involved and infiltrative growth was more common, compared to findings in patients who were recurrence-free. Peritoneal recurrence was evident in half the number of patients and the 5-year survival rate was 74. 5%. Tumor growth potential was evaluated, based on the level of proliferating cell nuclear antigen (PCNA) of the primary tumor and on dendritic cell infiltration into the tumor, determined as a level of local immune function of the host. Higher growth potential and lower immune levels were more frequent in patients with recurrences. Multivariate analysis revealed that tumor size and PCNA labeling index were significant prognostic factors for node-negative gastric cancers. In a subset of advanced gastric cancers, there was no apparent distinct lymph node metastasis and the prognosis was better. However, cancer cells with a higher growth potential and a lower immune response in the host can biologically amplify and mainly infiltrate the gastric wall, extend to the serosa and disseminate transserosally into the peritoneum.

Aged↗

PubMed1999

Role of transforming growth factor-beta 1 in invasion and metastasis in gastric carcinoma.

PURPOSE: Transforming growth factor-beta1 (TGF-beta1) is a major modulator of cellular proliferation and extracellular matrix formation. We determined the role of TGF-beta1 in invasion and metastasis in gastric cancer. MATERIALS AND METHODS: We detected TGF-beta1 expression in primary and lymph node metastatic lesions of gastric cancer, using an antibody and in situ hybridization. The plasma TGF-beta1 levels in the peripheral vein and in the tumor drainage vein were assayed. RESULTS: In the cytoplasm of cancer cells, TGF- beta1 was immunostained in 35.9% (78 of 217) of primary gastric carcinomas, and this expression was confirmed by in situ hybridization. Of 59 gastric carcinomas with a TGF-beta1-negative primary tumor, metastatic lymph nodes were positive for TGF-beta1 staining in 32 cases (54.2%). Positive staining of TGF-beta1 in gastric cancer tissues was closely related to serosal invasion, infiltrative growth, and lymph node metastasis. Multivariate analysis showed that the expression of TGF-beta1 was an independent risk factor for serosal invasion and infiltrative growth of the tumor. The plasma level of TGF-beta1 did not differ between TGF-beta1-negative and -positive groups. There were also no differences in plasma TGF-beta1 levels among each tumor stage, between the peripheral and the tumor drainage veins, and between preoperative and postoperative testings. CONCLUSION: Transforming growth factor-beta1 is closely related to the invasion and metastasis of gastric cancer, and production of TGF-beta1 in the tumor does not contribute to the total amount of TGF-beta1 in the blood circulation. We interpret our observations to mean that in a tumor microenvironment, TGF-beta1 alters the biologic behavior of the tumor.

Aged↗

PubMed1998

Multifocal occurrence of gastric carcinoma in patients with a family history of gastric carcinoma.

BACKGROUND: Smoking and alcoholic beverage drinking habits as well as a family history of cancer are well known risk factors for the multifocal occurrence of squamous cell carcinoma of the esophagus and the head and neck region. However, the role of these risk factors in multiple gastric carcinoma remains to be clarified. The purpose of this study was to examine the risk factors for multiple gastric carcinoma. METHODS: The smoking and drinking habits as well as the family history of 157 patients with synchronous multiple gastric carcinoma and 157 patients with solitary gastric carcinoma who were similar with regard to gender, age, stage of the tumor, and year of admission were investigated. The risk of a multiple occurrence of gastric carcinoma also was elevated using the odds ratio (OR). RESULTS: The ORs of a multifocal occurrence of gastric carcinoma in patients who currently smoked and drank alcoholic beverages were 1.1 and 0.8, respectively, although the ORs were not related to the quantity of smoking or drinking. In patients with a close relative with gastric carcinoma the OR was 2.1 (95% confidence interval [CI], 1.3-3.7). In those patients with > or =2 close relatives with gastric carcinoma, the OR increased to 5.1 (95% CI, 1.2-21.1). Conversely, no significant elevation in the ORs was recognized regarding a family history of other cancers. CONCLUSIONS: In this study, a family history of gastric carcinoma was found to be clearly associated with the multifocal occurrence of gastric carcinoma; however, no significant correlation between the multifocal occurrence of gastric carcinoma in these patients and their smoking and drinking habits was recognized.

Alcohol Drinking↗

PubMed1998

Family aggregation of carcinoma of the hypopharynx and cervical esophagus: special reference to multiplicity of cancer in upper aerodigestive tract.

The role of family history in the multiple occurrence of cancer in the upper aerodigestive tract (UADT) remains unclear. The family histories of close relatives were examined in 167 patients with either hypopharyngeal or cervical esophageal cancer (PhCe cancer) and in 167 control subjects with benign diseases. The odds ratio for PhCe cancer was 2.6 in relation to family history of UADT cancers. Based on the family histories of close relatives, 167 cases with PhCe cancer were divided into 3 groups (Group I, 18 cases with a family history of UADT cancer; Group II, 37 cases with a family history of other cancers; Group III, 112 cases with no family history of any cancers). The mean age of the cases in group I was 59.4, which was younger than in group III (64.2). Second primary squamous-cell carcinomas in the UADT were more frequently recognized in group I (39%) than in group III (11%). However, no differences were observed in the smoking and drinking habits of male patients between each group. These results thus suggest that a family history of UADT cancers appears to be associated with the multiple occurrence of UADT cancers as well as the development of PhCe cancer.

Aged↗

PubMed1998

Metabolic labeling of a subset of glial cells by UDP-galactose: implication for astrocyte lineage diversity.

Astrocytes are implicated in many aspects of brain function; however, it remains unclear whether astrocytes arise from a single cell lineage. It is therefore important to obtain new markers for the astrocyte cell lineage. We show that exogenously added UDP-galactose (UDP-Gal) can be used to metabolically label a subset of glial fibrillary acidic protein-positive (GFAP+) cells. UDP-Gal was incorporated into the cultured embryonic mouse brain slices in a time-dependent manner. Surprisingly, the transferred sugar moiety was no longer Gal but was mainly glucose. Most of the radioactivity was transferred to a polymer of glucose, most likely to be glycogen, and also to glucosyl ceramide. In the slice culture, the reaction products were distributed densely in the ventricular zone and also on process-like structures extending to the pial surface. In dissociation culture, UDP-Gal labeled some of the GFAP+ cells and some of the vimentin+ cells. Because radial glial cells (RGCs) contain glycogen and change from vimentin+ to GFAP+, it is strongly suggested that UDP-Gal labeled RGCs and their descendants. Only 27% of the GFAP+ cells were labeled with UDP-Gal, which suggests that only a subset of astrocytes are derived from RGCs and that there is a discrete group of GFAP+ cells that is not generated from RGCs.

Animals↗

PubMed1998

Muscarinic facilitation of GABA release in substantia gelatinosa of the rat spinal dorsal horn.

1. Blind patch clamp recordings were made from substantia gelatinosa (SG) neurones in the adult rat spinal cord slice to study the mechanisms of cholinergic modulation of GABAergic inhibition. 2. In the majority of SG neurones tested, carbachol (10 microM) increased the frequency (677 % of control) of spontaneous GABAergic inhibitory postsynaptic currents (IPSCs). A portion of these events appeared to result from the generation of spikes by GABAergic interneurones, since large amplitude IPSCs were eliminated by tetrodotoxin (1 microM). 3. The effect of carbachol on spontaneous IPSCs was mimicked by neostigmine, suggesting that GABAergic interneurones are under tonic regulation by cholinergic systems. 4. The frequency of GABAergic miniature IPSCs in the presence of tetrodotoxin (1 microM) was also increased by carbachol without affecting amplitude distribution, indicating that acetylcholine facilitates quantal release of GABA through presynaptic mechanisms. 5. Neither the M1 receptor agonist McN-A-343 (10-300 microM) nor the M2 receptor agonist, arecaidine (10-100 microM), mimicked the effects of carbachol. All effects of carbachol and neostigmine were antagonized by atropine (1 muM), while pirenzepine (100 nM), methoctramine (1 microM) and hexahydrosiladifenidol hydrochloride, p-fluoro-analog (100 nM) had no effect. 6. Focal stimulation of deep dorsal horn, but not dorsolateral funiculus, evoked a similar increase in IPSC frequency to that evoked by carbachol and neostigmine. The stimulation-induced facilitation of GABAergic transmission lasted for 2-3 min post stimulation, and the effect was antagonized by atropine (100 nM). 7. Our observations suggest that GABAergic interneurones possess muscarinic receptors on both axon terminals and somatodendritic sites, that the activation of these receptors increases the excitability of inhibitory interneurones and enhances GABA release in SG and that the GABAergic inhibitory system is further controlled by cholinergic neurones located in the deep dorsal horn. Those effects may be responsible for the antinociceptive action produced by the intrathecal administration of muscarinic agonists and acetylcholinesterase inhibitors.

(4-(m-Chlorophenylcarbamoyloxy)-2-butynyl)trimethy↗

PubMed1998

Submucosal gastric cancer with lymph node metastasis.

BACKGROUND AND OBJECTIVES: The intraoperative assessment of lymph node metastasis of gastric cancer remains difficult and the characteristics of recurrence after gastrectomy are not well known regarding submucosal cancer. METHODS: We examined 452 patients with submucosal gastric cancer and compared the clinicopathologic features as well as recurrence patterns between the 71 cases with lymph node metastasis (group I) and the 381 without it (group II). RESULTS: The mean tumor sizes were 44.8 and 33.5 mm, respectively (P < 0.01). The incidences of lymphatic invasion and vascular invasion were 91.5% (65/71) and 45.1% (32/71) in group I, which were significantly higher than those in group II (36.7 and 14.2%, 140/381 and 54/381, respectively, P < 0.01). A total of 21 patients (4.6%, 21/452) experienced recurrence after undergoing a gastrectomy and hematogenic recurrence was the most frequent type of recurrence (2.0%, 9/452). However, in group I, lymphatic recurrence was most frequently observed (7.0%, 5/71), and it was more frequent than in group II (0.3%, 1/381, P < 0.01). The median intervals between gastrectomy and recurrence were 34.5 and 64.0 months in groups I and II, respectively (P < 0.05). CONCLUSIONS: The submucosal cancer with larger size, lymphatic invasion, and vascular invasion has high risks for lymph node metastasis. Furthermore, a strict follow-up for lymphatic as well as hematogenic recurrence is important for the patients with node positive submucosal cancer, especially within 5 years after operation.

Female↗

PubMed1998

DNA index as a significant predictor of recurrence in colorectal cancer.

PURPOSE: To clarify the prognostic significance of the DNA content in cases of colorectal cancer, we investigated the relationship between the DNA content, as determined by the DNA ploidy or DNA index, and disease-free survival. RESULTS: This study included 201 cases that were treated by curative surgery between 1989 and 1995 at our hospital. 68 were diploid and 133 were aneuploid. The mean DNA index of these tumors was 1.42. Recurrence occurred in 30 cases (14.9 percent). Tumor site, venous invasion, Dukes stage, DNA ploidy (diploid or aneuploid), and a DNA index (less than or greater than 1.4) correlated well with disease-free survival. A multivariable analysis suggested the DNA index to be a stronger predictor than DNA ploidy. Patients with aneuploid tumors had shorter disease-free survival than those with diploid tumors (P = 0.011), especially in Dukes Stage C cases (P = 0.0209). Patients with a DNA index greater than 1.4 also had a shorter disease-free survival than those with a DNA index less than 1.4 (P < 0.001), especially in Dukes Stage C cases (P = 0.0033). CONCLUSIONS: The DNA index value (less than or greater than 1.4) seems to be a stronger predictor than DNA ploidy (diploid or aneuploid), and the combination of Dukes stage, tumor site, and a DNA index is, therefore, considered to be clinically valuable in predicting recurrence in cases of colorectal cancer.

Aged↗

PubMed1998

MST-16, a novel derivative of bis(2,6-dioxopiperazine), synergistically enhances the antitumor effects of anthracyclines.

MST-16, a derivative of bis(2,6-dioxopiperazine), is a newly developed anticancer agent that is potentially effective in combination with anthracyclines. It has a structural similarity to ICRF-187. The effects of MST-16 and its active form, ICRF-154, on the cytotoxic activities of six anthracyclines were investigated both in vitro and in vivo. Adriamycin (ADM), therarubicin (THP) and ME2303 (ME) showed synergistic cytotoxicity against colon 26 cells, when combined with MST-16. Epirubicin (EPI) and menogaril (TUT-7) and daunomycin (DM) all had a combination index of less than 1.0 only in the lower fraction affected range and, so there were probably no synergistic interactions between these drugs and MST-16. In colon 26 tumor-bearing mice, a significant delay in tumor growth was noted in the mice treated with ADM (7.5 mg/kg) and MST-16 (750 mg/kg) compared with mice given either drug alone. Similarly, tumor growth in mice treated with THP (10 mg/kg) or ME (10 mg/kg) with MST-16 (750 mg/kg) was significantly delayed. To elucidate the mechanism of synergy between these anthracyclines and MST-16, the concentration of anthracyclines in the treated cells was measured by flow cytometry. No increased intracellular accumulation of ADM. THP or ME was evident even when combined with MST-16. Cell cycle analysis revealed that MST-16 enhanced the accumulation of cells in G2M induced by ADM, THP and ME 1.6, 1.4, and 1.5 times, respectively. We thus conclude that the administration of ADM, THP and ME combined with MST-16 is synergistic and that the mechanism may not include an increase in the intracellular drug uptake but rather an increase in G2M accumulation.

Animals↗

PubMed1998

Histological investigation of spinal cord lesions in the spinal hyperostotic mouse (twy/twy): morphological changes in anterior horn cells and immunoreactivity to neurotropic factors.

We examined the morphology of spinal accessory motoneurons and immunoreactivity to neurotrophins, brain-derived neurotropic factor (BDNF) and neurotrophin (NT)-3, as well as the presence of reactive astrocytosis in 70 tiptoe walking Yoshimura (twy) mice that develop calcification at C1-C2 vertebral level compressing the spinal cord. At the level of compression, the area of neuronal soma and total length of dendrites of wheat germ agglutinin-horseradish peroxidase (WGA-HRP)-labelled accessory motoneurons in the medial cell pool decreased significantly with decrement in motoneuron population, relative to the control. In contrast, at sites rostral to the compressive lesion, a significant enlargement of the neuron soma and dendritic elongation were noted, associated with increased motoneuron population and decreased transverse area of the cord at the level of compression. At this site, enhanced BDNF and NT-3 immunoreactivities were evident in the anterior horn cells. In mice with a more severe degree of compression, astrocyte-like cells showing BDNF immunoreactivity became abundant and axons in the anterior column demonstrated a marked NT-3 immunoreactivity. Our results suggest increased functional activity of anterior horn cells at levels rostra] to the site of compression. We speculate that the presence of BDNF and NT-3 in neurons and astrocyte-like cells is proportionate to the severity of chronic mechanical compression and may contribute to the heterotropic neuronal reserve and survival.

Animals↗

PubMed1998

Prosthetic knee Candida parapsilosis infection.

We report a 77-year-old man who developed Candida parapsilosis infection following total knee arthroplasty. Knee joint effusion was noted 2 weeks after surgery, and repeated cultures of aspirated fluid established the diagnosis of Candida parapsilosis infection 4 weeks after surgery. Treatment consisted of debridement and lavage of the involved joint together with continuous irrigation with fluconazole for 4 weeks, followed by oral fluconazole for another 6 months. At 3 years follow-up, the patient was doing well and radiological examination of the affected knee showed a firm attachment of the prosthesis. We suggest that early identification of the causative organism followed by continuous irrigation and use of appropriate antifungal medication may prevent joint instability and spares the removal of the prosthesis.

Aged↗

PubMed1998

Evaluation of disk capture with a splint repositioning appliance: clinical and critical assessment with MR imaging.

OBJECTIVE: The purpose of this study was to evaluate disk repositioning clinically and through use of magnetic resonance imaging after the insertion of a disk repositioning appliance. STUDY DESIGN: Seventy-four patients with 82 temporomandibular joints showing middle to late opening movement click and closing movement click near maximum intercuspation were treated with a mandibular full-coverage repositioning splint. These joints were assessed clinically and by means of magnetic resonance imaging for disk recapture. RESULTS: According to clinical assessment, 75.6% (62/82) of the joints were treated successfully; no click was observed from the splinted mandibular position. When compared with the results of magnetic resonance imaging assessment, clinical assessment showed an accuracy rate of 91.5%, although the incidence of the false negatives was high (40%). CONCLUSIONS: The results of this study showed that about 70% of reducing displaced disks were captured with use of the disk repositioning appliance. And it was also suggested that magnetic resonance imaging is helpful to evaluate disk repositioning therapy.

Adolescent↗

PubMed1998

Cervical myeloradiculopathy with entrapment neuropathy: a study based on the double-crush concept.

In an attempt to formulate a standardised approach to the diagnosis and management of patients with the double-crush syndrome, we reviewed 65 surgical cases (39 men and 26 women) with cervical myeloradiculopathy associated with entrapment neuropathy in the arm by examining the clinical features, results of nerve conduction velocity studies and distribution of the vertebral levels of compression. Fifty-three patients (average age, 43 years) presented with a carpal tunnel syndrome at the wrist and cervical lesions (41 with spondylosis and 12 with ossified posterior longitudinal ligament), while 12 had a cubital tunnel syndrome at the elbow with cervical lesions (eight with spondylosis and four with ossification of the posterior longitudinal ligament). In the former group, the lesions were found mostly at C5-6 and C6-7 levels, while in the latter group involvement of C6-7 was frequently observed. Two patients in each group required additional cervical decompression after carpal or cubital tunnel release. A retrospective review of our patients suggested that it is reasonable to pursue an accurate diagnosis followed by treatment based on individual neurological and electrophysiological findings, but taking into consideration the significant level of physical impairment associated with cord compromise, we believe that it may be reasonable to perform a cervical decompression rather than peripheral nerve release in such cases. Our findings suggest that one should be aware of a double-crush during examination of patients complaining of neck and hand problems.

Adult↗

PubMed1998

Dumb-bell shaped tuberculous abscess across the greater sciatic notch compressing both sciatic nerves.

We report an instructive case of a 65-year-old man who presented with a dumb-bell shaped tuberculous abscess across the greater sciatic notch bilaterally compressing both sciatic nerves. Clinical symptoms progressed slowly and mimicked lumbar radiculopathy, thus delaying an accurate diagnosis. Anterolateral retroperitoneal and posterolateral gluteal approaches of the greater sciatic notch as well as the acetabulum on both sides were followed in order to provide safe viewing and resection of the abscess. The abscess wall was adherent to the sciatic nerve and surrounding blood vessels. The symptoms completely disappeared after resection of the abscess.

Abscess↗

PubMed1998

Solitary plasmacytoma of the spine associated with neurological complications.

We report eight patients with a solitary plasmacytoma of the spine associated with neurological complications. The patients included five men and three women with an average age at presentation of 59 years (range, 47 to 73 years). The tumour was confined to the thoracic spine in six cases, cervical spine in one and lumbar spine in one. Duration of symptoms ranged from 2.5 to 22 months. Treatment consisted of a combination of radiotherapy, melphalan and surgery. One patient progressed to multiple myeloma 7 years after surgery. Surgical treatment (anterior surgery in three cases and posterior surgery in five) produced neurological improvement in all patients. We stress the importance of an early diagnosis followed by appropriate treatment including surgery for this clinical entity and long-term follow-up to detect a disseminated disease.

Aged↗

PubMed1998

Relationship between gait and clinical results after high tibial osteotomy.

Thirty-two patients with primary osteoarthritis of the medial compartment of the knee were studied prospectively to assess the relationship between clinical results, limb alignment, and adduction moment of the knee. Clinical and radiographic examination and gait analyses were performed preoperatively and repeated at 6 months and at 1, 3, and 6 years after high tibial osteotomy. The preoperative peak adduction moment was high in 25 patients and low in seven. In both groups, the adduction moment of the knee decreased at 6 months after surgery but increased after that period. Alignment of the affected knee in both groups remained valgus after surgery (average femorotibial angle, 167 degrees-169 degrees). Clinical outcome in both groups improved after surgery and remained unchanged after 1 year. The peak adduction moment of the knee for the whole group significantly correlated with alignment and foot angle before and 6 years after surgery but did not correlate with stride length and walking velocity. In addition, only alignment was associated significantly with clinical results at 6 years. These results suggest that the preoperative peak adduction moment of the knee does not correlate with clinical or radiographic outcomes of high tibial osteotomy, provided sufficient valgus alignment is achieved at surgery.

Aged↗

PubMed1998

Effects of boron neutron capture therapy using borocaptate sodium in combination with a tumor-selective vasoactive agent in mice.

Boron neutron capture therapy (BNCT) destroys tumor cells by means of alpha particles and recoil protons emitted by 10B(n, alpha)7Li reaction. For BNCT to be effective, the tumor/normal tissue concentration ratio of 10B must be larger than 1.0, because neutron distribution is not selective. We examined the combination of 10B-enriched borocaptate sodium (BSH) with flavone acetic acid (FAA) as a model compound which causes vascular collapse in squamous cell carcinoma in mice (SCCVII tumors) and would increase the tumor/normal tissue concentration ratio of 10B. FAA (200 mg/kg, i.p.) was injected, and 5 min later BSH (75 mg/kg, i.v.) was administered, followed 15 to 180 min later by irradiation with thermal neutrons. The 10B concentrations were measured by prompt gamma ray spectrometry. Without FAA, tumor 10B concentrations were less than or equal to normal tissue concentrations at all time intervals, except that the concentrations were 1.7- to 2.7-fold greater in tumor than muscle at 15 and 180 min after injection of BSH. With FAA, 10B concentrations 2.1- to 6.9-fold greater in tumor than in muscle were achieved at all intervals tested. For blood and skin, significant differential accumulations were found in tumors at 120 and 180 min. Tumor/liver ratios were less than 1 at all times. Cell survival was determined by in vivo/in vitro colony assay, and increasing radiosensitization correlated with increasing tumor 10B concentrations, whether or not they were achieved with FAA. Tumor control rates, determined at 180 days after BNCT, similarly appeared to depend only on 10B levels at the time of irradiation. Because 10B levels correlate with the radiation response of tissues, a therapeutic gain would be expected whenever the tumor levels exceed normal tissue levels, such as in tumors located in muscle irradiated at 15-180 min after FAA + BSH, or in those in skin irradiated at 120 and 180 min.

Animals↗