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Biomedical subjects

M Fukuda

Publications and source records attributed to M Fukuda.

At least 487 records · Page 27Linked to original sources
PubMed1997

Growth inhibition of Helicobacter pylori by monoclonal antibody to heat-shock protein 60.

The H20mAb recognizing the 60-kilodalton protein, which existed in the outer membrane and was induced by heat shock at 42 C, was established. The molecule recognized with the mAb was a heat-shock protein 60 (HSP60) of Helicobacter pylori. To understand the role of HSP60 on the cell surface of H. pylori, whether or not H20mAb affects the growth of H. pylori was investigated. When bacteria were cultured with H20mAb, growth was markedly inhibited after 24 hr, although an initial 5 hr-incubation with the mAb induced no significant inhibition of H. pylori growth. The 24- and 48 hr growth of the bacteria after washing to remove the mAb at 5 hr was also inhibited though the inhibitory effect was not strong. In electron microscopical analysis, the spots with high electron density in the cytoplasm of the bacteria treated with H20mAb were increased, depending on the length of incubation time from 5 to 24 hr. After 24 hr treatment with H20mAb, bacterial destruction was also observed, indicating bactericidal activity by H20mAb. These results suggest that the HSP60 on the cell surface of H. pylori might have an essential role in the growth of the bacteria.

Amino Acid Sequence↗
PubMed1997

Gene mutation analysis and quantitation of DNA topoisomerase I in previously untreated non-small cell lung carcinomas.

To elucidate whether gene alterations of topoisomerase I (topo I) exist in untreated non-small cell lung carcinomas (NSCLC), polymerase chain reaction-single strand conformation polymorphism analysis was performed in forty-four NSCLC tissue samples. Gene alterations of topo I were sought in three regions, near codons 361 and 363, 533, and 722 and 729, where point mutations have been found in resistant tumor cell lines selected by chronic camptothecin exposure. In addition, nuclear topo I contents were determined by immunoblotting. No mobility shifts were observed compared to the pattern observed in a normal control at any of the three regions in any sample, whereas topo I levels showed an approximately 12-fold variation. The variation is remarkably large compared to those seen in previous in vitro and in vivo studies. The results suggest that mutations of topo I may not contribute to intrinsic resistance of NSCLC to camptothecins, but low topo I levels may account, at least in part, for the resistance.

Adenocarcinoma↗
PubMed1997

P-glycoprotein is positively correlated with p53 protein accumulation in human colorectal cancers.

To explore the relationship between mutant p53 and Pgp expression, we have examined the levels of both proteins in human colorectal adenocarcinomas. Serial frozen sections of 40 surgical samples were stained with an anti-Pgp (MRK16) and two different anti-p53 protein antibodies (Abs), PAb421 and PAb1801. Nineteen (47.5%) of 40 samples examined were positive for Pgp, and 18 (45%) of 40 were positive for p53. The samples that stained positively with PAb421 also stained positively with PAb1801. Pgp expression was detected in 13 (76.5%) of 17 samples that were positive for p53 using PAb421 and in 15 (83.3%) of 18 samples that were positive for p53 using PAb1801. Thus, we found that p53 and Pgp were co-expressed in a significant number of samples (P < 0.002). There was no relationship between Pgp or p53 protein accumulation and histologic grade or stage. The present results demonstrate that Pgp expression is closely associated with p53 protein accumulation in human colorectal cancers. These data provide evidence to support the idea that mutant p53 activates the MDR1 gene in vivo.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1997

Task-dependent representations in rat hippocampal place neurons.

It is suggested that the hippocampal formation is essential to spatial representations by flexible encoding of diverse information during navigation, which includes not only externally generated sensory information such as visual and auditory sensation but also ideothetic information concerning locomotion (i.e., internally generated information such as proprioceptive and vestibular sensation) as well as information concerning reward. In the present study, we investigated how various types of information are represented in the hippocampal formation, by recording hippocampal complex-spike cells from rats that performed three types of place learning tasks in a circular open field with the use of intracranial self-stimulation as reward. The intracranial self-stimulation reward was delivered in the following three contexts: if the rat 1) entered an experimenter-determined reward place within the open field, and this place was randomly varied in sequential trials; 2) entered two specific places, one within and one outside the place field (an area identified by change in activity of a place neuron); or 3) entered an experimenter-specified place outside the place field. Because the behavioral trails during navigation were more constant in the second task than in the first task, ideothetic information concerning locomotion was more relevant to acquiring reward in the second task than in the first task. Of 43 complex-spike cells recorded, 37 displayed place fields under the first task. Of these 37 place neurons, 34 also had significant reward correlates only inside the place field. Although reward and place correlates of the place neuron activity did not change between the first and second tasks, neuronal correlates to behavioral variables for locomotion such as movement speed, direction, and turning angle significantly increased in the second task. Furthermore, 6 of 31 place neurons tested with the third task, in which the reward place was located outside the original place field, shifted place fields. The results indicated that neuronal correlates of most place neurons flexibly increased their sensitivity to relevant information in a given context and environment, and some place neurons changed the place field per se with place reward association. These results suggest two strategies for how hippocampal neurons incorporate an incredible variety of perceptions into a unified representation of the environment: through flexible use of information and the creation of new representations.

Analysis of Variance↗
PubMed1997

Analysis of urinary red blood cells of healthy individuals by an automated urinary flow cytometer.

A newly developed automated urinary flow cytometer allows clear discrimination of erythrocytes from other solid components of urine. In this study, the normal range of the urinary erythrocyte count and the source of urinary erythrocytes in healthy individuals were investigated using this analyzer. For the diagnosis of the source of the urinary erythrocytes, Kitasato University Kidney Center criteria for this analyzer were applied. The subjects were 133 regularly employed volunteers (age range 20-48 years, mean 30.5) who noted no urinary tract symptoms and showed normal blood pressure, consisting of 41 females not in their menstrual period (age range 20-39 years, mean 24.8) and 92 males (age range 20-48 years, mean 33.1). Mid-stream voided urine was collected from these subjects using urine sampling cups, immediately transferred to 50-ml sterilized Spitz tubes, and analyzed within 30 min using the automated urinary flow cytometer. Urinary erythrocytes were derived from glomeruli in all samples of healthy subjects. The urinary erythrocyte count showed a logarithmic normal distribution. Values 2 SD of the urinary erythrocyte count in healthy individuals or higher were regarded as abnormal, and hematuria was considered to be positive when 11.0/microliter or more erythrocytes were observed by this analyzer. The finding by this analyzer corresponded to the report of Birch et al.

Adult↗
PubMed1997

Spatiotemporal expression of C-CAM in the rat placenta.

We investigated the expression of the immunoglobulin superfamily cell adhesion molecule, C-CAM, in developing and mature rat placenta. By immunohistochemical staining at the light microscopic level, no C-CAM-expression was seen before Day 9 of gestation, when it appeared in the trophoblasts of ectoplacental cones. On Day 10.5, spongiotrophoblasts and invasive trophoblasts around the maternal vessels of the decidua basalis were stained positively. On Day 12.5, C-CAM was detected in the spongiotrophoblasts of the junctional layer, but labyrinth trophoblasts and secondary giant trophoblasts were not stained. On Day 17.5, C-CAM was found only in the labyrinth and lacunae of the junctional layer. At this stage, both the labyrinth cytotrophoblasts of the maternal blood vessels and the endothelial cells of the embryonic capillaries were strongly stained. Placental tissues from gestational Days 12.5 and 17.5 were analyzed by immunoelectron microscopy to determine the location of C-CAM at the subcellular level. On Day 12.5, positive staining of the spongiotrophoblasts was observed, mainly on surface membranes and microvilli between loosely associated cells. On Day 17.5, staining was found primarily on the microvilli of the maternal luminal surfaces of the labyrinth cytotrophoblasts, and both on the luminal surface and in the cytoplasm of endothelial cells of the embryonic vessels. RT-PCR analysis and Southern blotting of the PCR products revealed expression of mRNA species for both of the major isoforms, C-CAM1 and C-CAM2. Immunoblotting analysis of C-CAM isolated from 12.5-day and 14.5-day placentae showed that it appeared as a broad band with an apparent molecular mass of 110-170 kD. In summary, C-CAM was strongly expressed in a specific spatiotemporal pattern in trophoblasts actively involved in formation of the placental tissue, suggesting an important role in placental development. In the mature placenta, C-CAM expression was confined to the trophoblastic and endothelial cells lining the maternal and embryonic vessels, respectively, suggesting important functions in placental physiology.

Animals↗
PubMed1997

Use of an osseointegrated implant for dental rehabilitation after cleft repair by periosteoplasty: a case report.

OBJECTIVE: We report here on a patient with unilateral cleft lip and alveolus who underwent dental rehabilitation of cleft alveolus using an osseointegrated implant after cleft repair by periosteoplasty. The patient, whose lateral incisor was congenitally missing, had periosteoplasty, followed by excellent bone formation at the cleft alveolus within 2 years. After the completion of orthodontic alignment of the maxillary dental arch, a Brånemark single-tooth implant was placed into the bone-formed alveolus. CONCLUSION: This treatment procedure offers an option of dental rehabilitation for the alveolar clefts of patients with cleft lip and/or palate.

Alveolar Process↗
PubMed1997

Bronchial artery aneurysm as a cause of atelectasis.

A 54-year-old nonsmoker female developed atelectasis of the anterior basal segment of the right lower lobe. A non-pulsating endobronchial tumor was observed bronchoscopically obstructing the right basal bronchus. The tumor was confirmed on arteriography to be a saccular aneurysm of the right bronchial artery. The aneurysm was treated with bronchial artery embolization. Bronchial artery aneurysm, without a predisposing disease, is quite rare, but should be considered as an etiological factor of atelectasis.

Aneurysm↗
PubMed1997

Short-latency somatosensory evoked potentials in patients with brain stem tumor: study of N20 and N18 potentials.

Short-latency somatosensory evoked potentials (SSEPs) elicited by median nerve stimulation were studied in 17 patients with brain stem tumor. A total of 35 SSEP records were obtained and classified into five groups: 13 in Group I, central conduction time (CCT) < 7.56 msec (within the normal limits); eight in Group II, CCT > or = 7.56 msec; nine in Group III, N20 potential was abolished; four in Group IV, N20 and N18 potentials were abolished; and one in Group V, N20, N18, and P14 potentials were abolished. These SSEP groups were correlated with the size and location of the brain stem tumor on magnetic resonance images. N20 potentials were unchanged in latency in patients with small localized gadolinium (Gd)-enhanced lesions. In contrast, the N20 potentials were abolished in patients with tumors extending to the dorsal pons and the upper medulla oblongata. The extent of nonenhanced low-intensity lesion did not correlate with the changes of the N20 potentials. The degree of the impairment of the N20 potentials reflected the severity of the clinical symptoms. The N20 potential can evaluate brain stem dysfunction caused by brain stem tumor. The N18 potentials were abolished in four patients, in whom the tumor extension (one Gd-enhanced lesion, three low-intensity lesions) involved not only the pons but also the medulla oblongata. Therefore, the N18 potentials are probably generated from the medulla oblongata.

Adolescent↗
PubMed1997

Hemifacial spasm resulting from facial nerve compression near the internal acoustic meatus--case report.

A 61-year-old female presented with a rare case of hemifacial spasm (HFS) resulting from facial nerve compression near the internal acoustic meatus. She underwent a first surgery for microvascular decompression at the root entry zone of the facial nerve, but this did not achieve resolution of the HFS. During the second surgery, the meatal loop of the anterior inferior cerebellar artery (AICA) was found to be the offending artery near the internal acoustic meatus. When the AICA was dissected and separated from the facial nerve, abnormal muscle responses of the mentalis muscle due to electrical stimulation of the zygomatic branch of the facial nerve were abolished. Following surgery the patient was completely free of the HFS.

Decompression, Surgical↗
PubMed1997

[Intraoperative monitoring for functional neurosurgery during intravenous anesthesia with propofol].

We studied the effects of propofol on electrophysiologic monitoring for functional neurosurgery. In six patients with intractable epilepsy, electrocorticograms (ECoGs) were monitored for epilepsy surgery, and in two of them, somatosensory evoked potentials (SEPs) were monitored because of the focus adjacent to the central sulcus. In four patients with hemifacial spasm, brain stem auditory evoked potentials (BAEPs) and abnormal muscle responses (AMRs) were monitored during microvascular decompression (MVD). In two patients with Parkinson's disease and in one patient with post-traumatic tremor, neural noise levels were recorded from microelectrodes during posteroventral pallidotomy and Vim thalamotomy. In each case of epilepsy surgery, during intravenous anesthesia with propofol, spike activity was recordable enough to identify the resective area and the residual spikes. SEP phase reversal was obtained in two patients and an exact determination of the central sulcus was possible. BAEPs and AMRs were obtained in all MVDs. To record neural noise levels, the infusion of propofol was decreased in two cases of posteroventral pallidotomy, and it was stopped in one case of Vim thalamotomy. In these patients, neural noise levels were recorded and were useful for identifying the target. Propofol is a potentially useful anesthetic agent for electrophysiologic monitoring during functional neurosurgery.

Adult↗
PubMed1997

Infection with GB virus C in patients with chronic liver disease.

Infection with putative non-A to E hepatitis virus, designated GB virus C (GBV-C), was surveyed in 286 patients with chronic liver disease in Japan. RNA of GBV-C was detected, by reverse-transcription polymerase chain reaction with nested primers from the 5'-noncoding region, in 19 patients (6.6%) at a frequency higher (P < 0.001) than in three of 275 (1.1%) normal controls. It was detected in three of 83 (4%) patients with hepatitis B virus infection, 15 of 188 (8%) patients with hepatitis C virus infection, and one of 12 (8%) patients without evidence of ongoing infection with hepatitis B or C virus. GBV-C RNA was detected in nine of 186 (5%) patients with chronic hepatitis aged 51.2 +/- 13.3 years, six of 64 (9%) with liver cirrhosis aged 62.9 +/- 11.4 years, and four of 36 (11%) with hepatocellular carcinoma aged 62.0 +/- 11.1 years. Nucleotide sequences of 100 base pairs in the helicase region of GBV-C isolates from the 19 patients varied up to 21%, while sequences of 33 deduced amino acids were conserved and differed only by up to 6%. These results indicate that infection with GBV-C in patients with non-B, non-C chronic liver disease would not be frequent, although the sensitivity of the detection method could be improved. Coinfection of GBV-C with hepatitis B or C virus, as well as the duration of infection, might accelerate the progression of chronic liver disease.

Amino Acid Sequence↗
PubMed1997

Duplex PCR of the Y-27H39 and HPRT loci with reference to Japanese population data on the HPRT locus.

Using a duplex polymerase chain reaction (PCR) system, we successfully amplified GATA microsatellite loci Y-27H39 and HPRT on the Y and X chromosomes, respectively, and detected their alleles with a digoxigenin-labeled (GATA)6 probe. Among 450 unrelated Japanese including 225 females, we found 6 HPRT alleles ranging from 155 to 175 nucleotides with a simple repeat structure comprising 11 to 16 repeats. The duplex PCR is highly informative in Japanese.

Alleles↗
PubMed1997

[Metastatic renal tumor originating from esophageal cancer: report of 2 cases].

We report 2 cases of esophageal cancer metastatic to the kidney. The first case was in a 57-year-old man who complained of severe right flank pain. He had underwent an operation for esophageal cancer 2 months previously. A computerized tomography (CT) scan revealed a wedge-shaped, low-density mass in the right kidney. Right nephrectomy revealed squamous cell carcinoma. He has remained free of recurrence 3 months postoperatively. The second case was in a 57-year-old man with esophageal cancer treated by radiation therapy. Severe right flank pain and gross hematuria appeared after 1 year. A CT scan showed a wedge-shaped, low-density tumor in the right kidney accompanied with a tumor thrombus in the inferior vena cava. Right nephrectomy as well as resection of the thrombus were performed. Pathological diagnosis was squamous cell carcinoma. He died of cancer 2 months postoperatively.

Carcinoma, Squamous Cell↗