Search PubMed⌕ Search

Biomedical subjects

H Maeda

Publications and source records attributed to H Maeda.

At least 505 records · Page 28Linked to original sources
PubMed1996

[Thoracoscopic enucleation for sclerosing hemangioma of the lung--a case report].

A 30-year-old female with sclerosing hemangioma of the lung (SHL) was managed by thoracoscopic enucleation. Under the left lateral decubitus position, four small skin incisions were made. The tumor, approximately 2.5 cm in diameter, was just under the pleura at the right S5, and was clearly demarcated without adhesions to mediastinal pleura. Because the tumor located near the hilum, a partial resection by intrathoracic Endo-GIA could not be performed. So the tumor was enucleated bluntly with an electrode knife being tugged by a tractive thread. After it was diagnosed as SHL by intraoperative imprint cytology, the stump was closed with running suture of 3-0 nylon. The patient was discharged on the 10th postoperative day without complication. No recurrence was found during a follow-up period of six months after the operation. Immunohistochemical findings suggested that the tumor cells were derived from type II pneumocytes. Thoracoscopic surgery appears to be a good indication for SHL which commonly occurs in young or middle-aged women and which is difficult to be diagnosed preoperatively. Thoracoscopic enucleation is considered to be a one of the safe methods especially for SHL which can not be resected by Endo-GIA.

Adult↗
PubMed1996

Differential display of messenger RNA expressed in bronchoalveolar lavage cells in pulmonary sarcoidosis patients.

Sarcoidosis is a systemic granulomatous disease of unknown origin. To clarify its pathogenesis, we searched for known or unknown genes which are specifically expressed in sarcoidosis. Bronchoalveolar lavage (BAL) cells from 18 patients with sarcoidosis and 8 patients with various lung diseases were analyzed by differential display method. mRNA was extracted from BAL cells and reverse transcribed with 12 kinds of anchored primer, which theoretically cover all mRNAs, followed by polymerase chain reaction (PCR) with the anchored primer and a 10-mer arbitrary primer. PCR products were displayed on a polyacrylamide gel and fragments showing characteristic alterations in intensity between sarcoidosis and other patients were extracted, sequenced, and compared against Genbank and EMBL DNA data bases. One fragment was detected with specifically increased intensity and another disappeared in patients with sarcoidosis. These fragments were likely derived from unknown genes. CD44 and tumor necrosis factor (TNF-alpha) cDNA sequences were also detected as fragments commonly expressed in sarcoidosis. The cloned fragments with specifically increased or decreased intensity in sarcoidosis may provide important information on the pathogenesis of sarcoidosis, and the display pattern implies the potential usefulness of this method as a tool for diagnosis of the disease.

Adolescent↗
PubMed1996

Gene expressions of basic fibroblast growth factor and its receptor in healing of rat retina after laser photocoagulation.

Basic fibroblast growth factor (bFGF) stimulates the mitogenesis of various cells and plays a key role in wound repair. Using in situ hybridization, we studied mRNA expressions of bFGF and one of its receptors, FGF receptor 1 (FGFR1), during wound repair of the rat retina after laser photocoagulation. Gene expressions of bFGF and FGFR1 were detected in the ganglion cell and inner nuclear layers of the normal adult rat retina. On day 3 following laser photocoagulation, proliferating retinal pigment epithelial (RPE) cells of the lesion showed intense gene expressions of bFGF and FGFR1. Macrophage-like cells that migrated into the lesion also showed gene expression of bFGF. These gene expressions decreased over time. The finding of elevated gene expressions of bFGF and FGFR1 after laser photocoagulation suggests the bFGF may be a factor in retinal wound repair.

Animals↗
PubMed1996

Augmentation of parasympathetic nerve function in patients with extrinsic bronchial asthma--evaluation by coefficiency of variance of R-R interval with modified long-term ECG monitoring system.

Patients with bronchial asthma (BA) have evidence of increased vagal cholinergic tone. Although the cardiovascular-respiratory tests used in the past might have been biased by concomitant chest disease, coefficiencies of variance of the R wave to R wave (RR) interval (CVR-R) on electrocardiogram (ECG) have been applied to many diseases as a method of functional evaluation of the parasympathetic nerve system. In 24 hour recordings of ECG (Holter ECG), continuous values of CVR-R have been determined for each one-minute period with a recently developed long-term ECG monitoring system. To examine functional augmentation of parasympathetic nerve in patients with BA, we applied this system in the present study to determine the alteration of parasympathetic nerve function during an inhaled methacholine provocation test in 14 patients and 7 healthy subjects. CVR-R values were calculated from the collection of a 24-hour electrocardiogram. Bronchial response, which was measured by methacholine inhalation, was evaluated with the baseline value of respiratory resistance (Rrs-cont), the cumulative dose producing a 35% decrease in respiratory conductance (PD35Grs) and the minimum cumulative dose required to start to decrease respiratory conductance from baseline (Dmin). The serum concentrations of epinephrine and norepinephrine were measured at the basal and double-increased levels of respiratory resistance during the inhalation test. The increased values of CV(R-R) in asthmatic patients were intimately associated with augmented respiratory resistance. The disparity of CV(R-R) values (delta CV) during the resistance levels from basal to double in the asthmatic group was significantly greater than that in the control group. The absolute change of CV(R-R) values in the asthmatic group was significantly larger than that in the control group. There was a significant correlation between delta CV and Dmin (r = 0.536, p < 0.05), and between delta CV and PD35Grs (r = 0.552, p < 0.05). The serum concentrations of epinephrine and norepinephrine were not significantly different during the methacholine inhalation provocation test. We conclude that alteration of the values of CV(R-R), which were calculated with a modified long-term ECG recording system, may reflect the change of parasympathetic nerve function and the severity of bronchial hyperreactivity, and this system can be a useful non-invasive method for evaluation of increased vagal tone in patients with bronchial asthma.

Adult↗
PubMed1995

Experimental studies on postmortem diffusion of ethanol-d6 using rats.

In an investigation of postmortem ethanol diffusion deuterium-labeled ethanol-d6 was instilled by peroral gavage immediately after death by CO into the stomach of rat carcasses which were subsequently kept for 12-72 h at 5 or 30 degrees C. The heart blood, abdominal fluid and several tissues were collected and analyzed by head space gas chromatography-mass spectrometry. Rat carcasses showed no macroscopic changes until at least 72 h at 5 degrees C, and 12 h at 30 degrees C. At 30 degrees C, slight macroscopic change was observed after 24 h, moderate change after 48 h and marked change after 72 h. In the abdomen ethanol-d6 diffused gradually into neighboring organs (hepatic left lobe, left kidney and spleen) at 5 degrees C, with ethanol-d6 reaching a peak concentration of 0.75-2.38 mg/g at 24 h. At 30 degrees C, ethanol-d6 was also detected in neighboring organs and reached a peak concentration of 1.06-2.61 mg/g at 12 h. Thereafter, the ethanol-d6 concentration in the liver, kidney and spleen decreased, with concentrations ranging from 0.30 to 0.61 mg/g at 30 degrees C and 0.05 to 1.47 mg/g at 5 degrees C at 48 h. In the femoral skeletal muscle, ethanol-d6 was not detected until 24 h or more storage at 30 degrees C and never detected at 5 degrees C. In the brain and the organs in the thoracic cavity ethanol-d6 was detected after 12 h or more at 5 or 30 degrees C. Comparison of these results of direct peroral gastric instillation with those when ethanol-d6 was injected into the stomach through a laparotomy incision suggest that the brain and thoracic cavity changes were a result of diffusion from the mouth and esophagus. After 24 h at 30 degrees C, the postmortem ethanol production (0.33-0.85 mg/g) was comparable to those in previous reports. These results indicate that the assessment of ethanol concentration in the heart blood and organs in autopsy cases must be carefully conducted in comparison with the alcohol content of the stomach.

Animals↗
PubMed1995

Postmortem degradation of administered ethanol-d6 and production of endogenous ethanol: experimental studies using rats and rabbits.

Deuterium-labeled ethanol-d6 was employed to study the metabolism and postmortem change of ethanol in putrefied organ tissues. First, 4 ml/kg body weight of 25% (w/v) solution of ethanol-d6 was administered orally to each of 15 rats. The heart blood and organs were collected 15-90 min after the administration and the ethanol-d6 was analyzed by head space gas chromatography/mass spectrometry. The ethanol-d6 concentration in the organ tissues reached its maximum at 15 min after the administration and then gradually declined, showing the same pattern as human ethanol metabolism. Ethanol-d6 (3 ml of the same solution/kg body weight) was injected into the vein of a rabbit's ear (total of 12 rabbits). The rabbit was killed with carbon monoxide 30 min after the administration and the carcass was allowed to stand for 1-4 days at 30 degrees C in a moist chamber. The concentration of ethanol-d6 decreased moderately. Postmortem ethanol and 1-propanol concentrations, in contrast, showed marked increases 2.5 days and more after sacrifice in line with the degree of putrefaction of each organ tissue including skeletal muscle. This suggests the postmortem activation of micro-organism activity. These results indicate that ethanol concentrations in cadaver tissues must be carefully assessed with due consideration of postmortem degradation and production.

1-Propanol↗
PubMed1995

TGF-beta enhances macrophage ability to produce IL-10 in normal and tumor-bearing mice.

In the present study, we demonstrate that TGF-beta is capable of enhancing macrophage ability to produce IL-10 in normal and EL4 tumor-bearing mice. We found the increase in IL-10 in ascitic fluid and IL-10 mRNA expression in macrophages in parallel with the TGF-beta level and tumor progression. The macrophage production of IL-10 in the tumor-bearing mice was significantly enhanced without LPS stimulation in vitro, compared with normal controls. To clarify the mechanism wherein increased IL-10 production was induced, anti-TGF-beta or anti-IL-10 Abs were administered to EL4-bearing mice. Administration of anti-TGF-beta Ab led to a reduction in the IL-10 contents in ascitic fluid of tumor-bearing mice; however, anti-IL-10 Ab administration did not prevent the increase in TGF-beta contents. Enhanced IL-10 production and mRNA expression of macrophages from the tumor-bearing mice were also reduced by anti-TGF-beta Ab administration. Both anti-TGF-beta and anti-IL-10 Ab administration restored the TNF-alpha production by macrophages in EL4-bearing mice. In normal macrophages, in vitro pretreatment with TGF-beta 1 potentiated IL-10 production, and when natural TGF-beta 1 was administered to normal mice, the recovered peritoneal macrophages showed enhanced IL-10 production. Based on the above findings it can be concluded that TGF-beta enhances macrophage ability to produce IL-10, which sheds a new light on the role of TGF-beta in the immune system.

Animals↗
PubMed1995

Participation of a proton-cotransporter, MCT1, in the intestinal transport of monocarboxylic acids.

A molecular mechanism for the intestinal monocarboxylic acid transport was characterized by using a proton/monocarboxylate transporter, MCT1, in Chinese hamster ovary (CHO) cells, first found by Garcia et al. (Cell, 76, 865-873, 1994). Northern blotting analysis showed that MCT1-isomers exist in the rat and rabbit intestinal enterocytes and Caco-2 cells. The expression of [14C]lactic acid uptake by Xenopus laevis oocytes injected with rabbit intestinal mRNA was reduced by hybridizing the mRNA with a MCT1 cDNA of CHO cells before microinjection used as the antisense DNA. [14C]Lactic acid uptake by CHO cells was pH dependent, saturable, stereospecific, and reduced in the presence of acetic acid, benzoic acid, S- and R-ibuprofen, S- and R-mandelic acid, nicotinic acid, pravastatin, propionic acid and valproic acid. In addition, several monocarboxylic acids were transported in pH-dependent and saturable manners. These results suggest that the intestinal MCT1-related protein contributes to a carrier-mediated absorption for organic weak acid compounds.

Animals↗
PubMed1995

Molecular miscibility of phosphatidylcholine and phosphatidylethanolamine in binary mixed bilayers with acidic phospholipids studied by 2H- and 31P-NMR.

The intermolecular interactions and microscopic miscibility of the lipid bilayers of single component and binary mixtures with high content of saturated fatty acids were investigated by 2H- and 31P-NMR for phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylglycerol (PG) and cardiolipin (CL). Their glycerol backbones were selectively deuterated by biosynthesis and chemical synthesis. Deuterium quadrupole splittings and phosphorus chemical shift anisotropies provided the consistent information for the molecular miscibility of each phospholipids. PE was found to be completely miscible with PG and CL. Since deuterium quadrupole splittings and phosphorus chemical shift anisotropy are identical for two components in the mixed bilayer, the dynamic structure from the glycerol backbone to phosphate group should be uniform in the binary mixture of these phospholipids. In contrast to PE, PC was not fully miscible with PG and CL at molecular resolution. The dynamic structure from the glycerol backbone to phosphate group is different for two components in the binary mixed bilayers. In the case of the mixed bilayers of PC and PE, both phospholipids are microscopically immiscible with each other. Thus, while PE, PG and CL can adapt to a new situation to form a uniform dynamic structure in mixed bilayers, PC has no ability for adaptation. The molecular miscibility in lipid bilayers was shown to depend on the molecular species and the nature of the molecular interactions. The biological significance of this result was discussed.

Lipid Bilayers↗
PubMed1995

HLA-DR8 and acute anterior uveitis in ankylosing spondylitis.

OBJECTIVE: To identify possible factors in the development of acute anterior uveitis (AUU) in patients with ankylosing spondylitis (AS). METHODS: We investigated HLA antigens serologically, and HLA-DRB1*08 alleles by polymerase chain reaction-restriction fragment length polymorphism, in 42 Japanese AS patients with and without AAU. RESULTS: Thirty-six of the AS patients (85.7%) had HLA-B27. Thirteen (65%) of the 20 patients with AAU had HLA-DR8, whereas only 1 (4.5%) of the 22 patients without AAU had DR8. The difference was statistically significant (Pcorr < 0.001). CONCLUSION: Our data suggest that HLA-B27 is strongly associated with AS in Japanese patients and that HLA-DR8 is important for the development of AAU in Japanese patients with AS.

Acute Disease↗
PubMed1995

Rhythmic Cl- current and physiological roles of the intestinal c-kit-positive cells.

Chronic injection of an anti-c-KIT receptor tyrosine kinase monoclonal antibody (ACK2) results in the disruption of the normal motility patterns of young BALB/c mice intestine. This effect is accompanied by a drastic decrease in the number of intestinal c-kit-expressing (c-kit+) cells when studied immunohistochemically with the fluorescence-labelled antibody. In order to clarify the mechanism underlying the ACK2 action and the physiological roles of intestinal c-kit+ cells, we studied the excitability of intestinal c-kit+ cells in primary culture by use of the nystatin perforated-patch-clamp technique. Under voltage-clamp at -40 mV, the majority of c-kit+ cells tested (59/70) elicited rhythmic current waves with an amplitude and frequency of 263 +/- 24 pA and 2.30 +/- 0.25 cycles/min (mean +/- SEM), respectively. Intracellular perfusion of the c-kit+ cells with ethylenebis (okonitrilo) tetraacetate (EGTA) as well as a nominally Ca(2+)-free external solution or low holding voltage (< -60 mV) prevented the rhythmic current. The reversal potential of the rhythmic current was close to the equilibrium potential for Cl-(ECl). Moreover the rhythmic current was depressed by a Cl- channel blocker, 4-acetoamido-4-isothiocyanat-ostilbene-2,2'-disulphoni c acid (SITS). The smooth muscle cells freshly dissociated from the same intestinal specimen revealed a Ca(2+)-activated K+ current, as has been described in a variety of smooth muscle cells. Cultured smooth muscle cells from the ileum preparation lacked neither the Ca(2+)-activated K+ nor rhythmic Cl- currents. Smooth muscle cells freshly dissociated from the same ileum preparation and those in culture showed no immunoreactivity with the labelled ACK2, which was consistent with our previous in situ study. Results provided direct evidence that the intestinal c-kit+ cells, but not the smooth muscle cells, possess a rhythmic Cl- current oscillation, suggesting their participation in pacemaker activity for the peristaltic gut movement.

4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfo↗
PubMed1995

Bone metabolic markers in bone metastases.

The efficacy and cost/performance benefit of radionuclide bone scintigraphy in monitoring metastatic bone activity remain controversial. Recently developed bone metabolic markers are expected to play an additional role in the diagnosis of bone metastasis. We measured osteoclastic and osteoblastic markers in 267 patients with breast cancer (100 with bone metastasis), 38 patients with prostatic cancer (25 with bone metastasis), 50 patients with lung cancer (12 with bone metastasis) and 33 patients with miscellaneous cancers (13 with bone metastasis) and compared the values in the presence and absence of bone metastasis. Bone metabolic markers, both osteoclastic and osteoblastic, increased significantly in patients with bone metastasis. In breast cancer (bone metastasis is mostly of the mixed type), osteoclastic markers were good in detecting bone metastasis. In prostatic cancer (bone metastasis is mostly osteoblastic), osteoclastic and osteoblastic markers were equally effective in detecting bone metastasis. In lung cancer (bone metastasis is mostly osteolytic), osteoclastic markers were elevated preferentially in bone metastasis. Over all, osteoclastic markers were more sensitive in the diagnosis of bone metastasis, and among osteoclastic markers, serum pyridionoline-cross-linked carboxyterminal telopeptide was the most efficient in both specificity (91.0%) and sensitivity (48.6%) for detecting bone metastasis.

Aged↗
PubMed1995

Antitumor resistance induced by zinostatin stimalamer (ZSS), a polymer-conjugated neocarzinostatin (NCS) derivative. I. Meth A tumor eradication and tumor-neutralizing activity in mice pretreated with ZSS or NCS.

Zinostatin stimalamer (ZSS) is a new anticancer agent derived from neocarzinostatin (NCS), which is synthesized by conjugation of one molecule of NCS and two molecules of poly(styrene-co-maleic acid). ZSS exhibited potent in vitro and in vivo antitumor activity in preclinical experiments, and a clinical trial of the intra-arterial administration of ZSS with iodized oil on hepatocellular carcinoma showed potent antitumor activity. We investigated the effect of ZSS and NCS on antitumor resistance and found that pretreatment with either drug suppressed the growth of MethA tumors in Balb/c mice and induced tumor eradication when given separately by single administration at therapeutic doses between 1 day and 4 weeks before tumor transplantation. The findings that the cytocidal activity of these drugs was not detected in vivo at the time of tumor transplantation and that tumor regression was preceded by a period of transient growth suggested that tumor regression was due to host-mediated antitumor activity induced by these drugs. Pretreatment with ZSS or NCS also suppressed the growth of Colon 26 carcinoma and Sarcoma 180. The finding that NCS showed the same effect as ZSS suggests that poly(styrene-comaleic acid) is not essential for the induction of host-mediated antitumor activity. Furthermore, apo-ZSS, which lacks cytocidal activity, did not induce antitumor activity. From this, it is suggested that the cytocidal effect of ZSS involves the induction of host-mediated antitumor resistance. In athymic Balb/c nu/nu mice, pretreatment with ZSS or NCS did not induce tumor eradication, suggesting that mature T lymphocytes play an important role in tumor eradication. Challenging MethA was rejected without transient growth in mice that had been cured of MethA, but challenging Colon 26 was not, showing that anti-MethA resistance was augmented selectively in the MethA-eradicated mice. Splenocytes from MethA-bearing mice pretreated with the drug showed tumor-neutralizing activity beginning 14 days after tumor transplantation. Tumor-neutralizing activity was only induced after MethA transplantation. The effector cells of this tumor-neutralizing activity were Thy1.2+ T lymphocytes that had been passed through a nylon-wool column, but no significant augmentation of cell-mediated cytotoxic activity of splenocytes from MethA-eradicated mice was observed in vitro.

Animals↗
PubMed1995

Immunohistochemical distribution of surfactant apoproteins in hypoplastic lungs of nonimmunologic hydrops fetalis.

Forty-three patients with nonimmunologic hydrops fetalis (NIHF), including 32 patients (74%) with hypoplastic lung, were immunohistochemically examined for the expression of surfactant apolipoproteins (SPs), using anti-gamma G immunoglobulins against human SP-A with a molecular weight (MW) of 35 K and SP-B with a MW of 5 K compared with that in 59 patients in a control group and 45 patients with hypoplastic lung induced by causes other than NIHF. In the control group, SP-A was expressed in the lungs from 23 gestational weeks and became more numerous and intense in alveolar type II cells after 31 gestational weeks, whereas SP-B began to be expressed from 20 gestational weeks, and almost all patients showed a diffuse positivity after 26 gestational weeks. In the NIHF group, SP-A expression was generally weak, even after 31 gestation weeks. Moreover, most of the patients showing a weak expression of SP-A were also associated with hypoplastic lung and had a clinical history of persistent intrauterine pleural effusion of more than 2 weeks. Conversely, the immunoreactivity of SP-B was well preserved in NIHF cases either with or without hypoplastic lung. These results suggest that in the NIHF lung, there is a possible delay in the functional maturation or development of SP-A synthesis by alveolar type II cells, and this retardation of the functional maturation in type II cells also participates in the postnatal respiratory insufficiency in NIHF.

Antibodies, Monoclonal↗