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Biomedical subjects

M Yagi

Publications and source records attributed to M Yagi.

At least 109 records · Page 6Linked to original sources
PubMed1996

Intestinal motility after massive small bowel resection in conscious canines: comparison of acute and chronic phases.

To evaluate intestinal function after 80% massive distal small bowel resection (MSBR), we continuously monitored interdigestive and postprandial bowel motility using bipolar electrodes and/or contractile strain gauge force transducers in conscious beagle dogs before and at 2-4 weeks (acute postoperative phase; acute phase) and 8-13 months (chronic postoperative phase; chronic phase) after the surgery. Fasting duodenal migrating myoelectric (or motor) complexes (MMC) occurred at longer intervals in the acute phase after 80% MSBR than in control beagles. Intervals between duodenal MMC in the chronic phase were similar to those found in control beagles. MMC arising from the duodenum were often interrupted before the jejunum above the anastomosis in the acute phase, and a slight recovery of propagation frequency to the jejunum above the anastomosis was observed in the chronic phase. However, duodenal MMC did not migrate smoothly to the terminal ileum in both groups. In the acute phase, the velocity of duodenal MMC propagation was slowed in every intestinal segment, including the duodenum and the jejunum above the anastomosis, and had not recovered even long after the operation. The duration of the postprandial period without duodenal MMC was prolonged significantly in the acute phase postoperatively. Although it shortened in the chronic phase, it still remained significantly longer than in controls. These findings suggest that changes in gut motility after MSBR tend to compensate for the shorter intestine and maintain small bowel absorption early postoperatively. However, these compensatory changes decrease over the long term, and their adaptive contributions to increased intestinal absorption may decrease as well.

Anastomosis, Surgical↗
PubMed1996

Isolation of methicillin-resistant coagulase-negative staphylococci from chickens.

Methicillin-resistant coagulase-negative staphylococci were isolated from the nares and skin of 1- to 8-week-old healthy chickens in three flocks from a farm. Isolation of methicillin-resistant coagulase-negative staphylococci was positive for 72 (25.7%) of the 280 chickens tested, with the frequency varying from 2.2 to 100% according to flock. A total of 45 appropriate isolates were selected and subjected to identification. Of the 45 methicillin-resistant coagulase-negative staphylococcal isolates selected, 37 were identified as Staphylococcus sciuri, 5 were identified as Staphylococcus epidermidis, and 3 were identified as Staphylococcus saprophyticus. The distribution of the species was different among the flocks. Comparative analysis of the SmaI-digested chromosomal DNA by pulsed-field gel electrophoresis revealed that the isolates could have originated from a single clone of each of S. sciuri and S. saprophyticus and three clones of S. epidermidis. By two methods based on the PCR technique, the mecA gene was detected in all five representative isolates of each methicillin-resistant coagulase-negative staphylococcal clone. The nucleotide sequence of a PCR fragment obtained from an isolate of S. sciuri was completely identical to the corresponding region of mecA genes reported in human methicillin-resistant Staphylococcus aureus isolates and Staphylococcus epidermidis isolates. The representative methicillin-resistant coagulase-negative staphylococcal isolates were resistant to many beta-lactam antibiotics, and some isolates were also resistant to macrolide and aminoglycoside antibiotics. This is the first evidence of the existence of methicillin-resistant coagulase-negative staphylococci from animals possessing the mecA gene.

Animals↗
PubMed1996

[Changes in intestinal motility after massive small bowel resection with a reversed jejunal segment].

To evaluate the functioning and effectiveness of a 20-cm reversed jejunal segment after 75-80% massive small bowel resection (MSBR), and whether migrating polarity changes or not, we continuously measured the postoperative bowel motility (using bipolar electrodes and/or contractile strain gage force transducers) in interdigestive and postprandial conscious dogs in short- (2-5 weeks) and long-term (6-10 months) after surgery. The fasting migrating myoelectric (or motor) complex (MMC) arising from the duodenum was often interrupted at the jejunum above the proximal anastomosis and did not migrate smoothly to the reversed segment or terminal ileum. In addition, brief small discordant contractions were frequent in the jejunum above the proximal anastomosis and the proximal part of the reversed segment. The duodenal MMCs predominantly propagated to the ileum through the inherent anatomic continuity of the bowel. These findings of the MMC propagation pattern are very similar in short- and in long-term after surgery. The duration of the postprandial period without duodenal MMC activity was markedly longer in short-term, but shorter in long-term (both were significantly longer than in controls). Marked dilatation of the jejunum and reversed jejunal segment was noted across the proximal anastomosis. These results suggest that the transit time and passage of intestinal contents can be delayed and stagnated for at least 10 months after MSBR with a 20-cm reversed jejunal segment. Although, reports on the polarity of peristalsis in the reversed segment in long-term followup have been contradictory in both experimental and clinical studies, this results support the conclusion that the reversed jejunal segment maintains its inherent propagative polarity and pattern over a long postoperative period.

Anastomosis, Surgical↗
PubMed1996

Kinetic analysis of cell proliferation using bromodeoxyuridine labeling and in situ detection of dying cells in the tympanic membrane and middle ear cholesteatoma.

Using specimens from the posterior-superior quadrant of the human tympanic membrane, meatal skin, retroauricular skin and middle ear cholesteatoma, epidermal cell proliferation was studied by cultures in FC43 emulsion containing bromodeoxyuridine (BrdU), and cell death was detected by in situ labeling of nuclear DNA fragmentation (TUNEL staining). The culture of specimens with BrdU revealed labeling in the basal cell layer and/or the layer immediately above it. The counts of BrdU-labeled cells both at and beside the malleus handle and at the annulus were significantly higher than those in the tympanic membrane, meatal skin, retroauricular skin and cholesteatoma, indicating the existence of epidermal proliferation centers in the annulus and malleus handle. TUNEL-positive cells were observed in the uppermost layer of the epidermis, and counts of dying cells did not show any significant differences among specimens from the different areas. From these observations, we conclude that addition of newly proliferated cells at the proliferation center and uniform cell death cause epidermal cell migration over the tympanic membrane and ear canal. In addition, no proliferation center was seen in the epidermis of cholesteatoma, suggesting a disturbance of epidermal cell migration. Furthermore, BrdU-labeling at the margin of persistently perforated tympanic membranes from patients with chronic otitis media revealed that, at the perforation margin, the counts of BrdU-labeled cells were not higher than those of the normal tympanic membrane. In addition, a few BrdU-labeled cells were observed in the lamina propria and mucosal cell layer, indicating that persistent perforation of the tympanic membrane results from the failure of proliferating cells to increase at the margin of the perforation.

Adolescent↗
PubMed1996

[Hearing acuity in the elderly in Japan].

In Japan, the elderly population has progressively increased. It is therefore expected that various social services for the elderly will be demanded. As most of the elderly have hearing impairment due to presbycusis, it is difficult to communicate smoothly with them. To provide the various social services, it is necessary to investigate hearing acuity in the elderly. Accordingly, the Hearing Research Group, which belongs to the Research Project on Aging and Health in the Ministry of Health and Welfare of Japan, investigated the hearing acuity of people 65 years old, or more. One thousand one hundred ninety two subjects were divided into five groups, Group A consisted of 170 males and 216 females between 65 and 69 years old, Group B, 186 males and 158 females between 70 and 74; Group C, 147 males and 140 females between 75 and 79; Group D, 63 males and 61 females between 80 and 84; and Group E, 29 males and 22 females 85 years old or more. We examined the 175 subjects 80 years old or more. Therefore, it is considered that this study could indicate the present condition of hearing acuity of the elderly of Japan. The average hearing levels measured at seven frequencies (125, 250 and 500Hz, and 1, 2, 4, and 8KHz) were 35.0dB in group A, 42.1 in group B, 46.1 in group C, 52.1 in group D, and 55.6 in group E. There were no differences in the average hearing level between males and females in any group. The audiogram pattern indicated a gradually descending curve in most subjects in all groups. The average speech discrimination rate was 75.4% in group A, 70% in group B, 63.8% in group C, 59.7% in group D, and 52.1% in group E. The percentage of subjects showing a short increment sensitivity index of more than 70% was 45.2% in group A, 49.3% in group B, 47.9% in group C, 51.6% in group D, and 59.7% in group D. In conclusion, hearing loss due to aging tended to be more progressive at higher frequencies while hearing acuity of frequencies covering normal speech was preserved. However, the speech discrimination rate decreased relative to changes in the pure tone hearing level. It was considered that the pathology of hearing loss due to aging begins with retrocochlear changes and cochlear factors are added to retrocochlear changes with aging.

Aged↗
PubMed1996

Liver transplantation for hepatocellular carcinoma: consideration from the findings on autopsy.

Extrahepatic spread of hepatocellular carcinoma was investigated in twenty autopsy cases with unresected hepatocellular carcinoma to define the appropriate patient selection criteria for liver transplantation. Diagnosis of extrahepatic spread of cancer by diagnostic imaging was not easy, and unsatisfactory prognosis after liver transplantation in patients with hepatocellular carcinoma might have been attributed to the high incidence of extrahepatic occult foci of cancer. All patients with multiple nodular, massive and diffuse tumor had extrahepatic spread of cancer. Only patients with a single nodular type tumor, no larger than 30 mm in diameter, had no extrahepatic metastasis, and these patients are the preferred candidates for liver transplantation.

Aged↗
PubMed1996

[Analysis of the p16INK4, p15INK4B genes abnormality and the amplification of cyclin D1 gene in esophageal cancer].

To evaluate the prognostic significance of gene amplification and overexpression of cyclin D1 in the patients of esophageal squamous cancer, slot blot hybridization and immunohistochemical staining were performed. The patients with gene amplification or overexpression of cyclin D1 were significantly poorly prognosis than patients these were negative. And to investigate abnormality of p16 and p15 genes in 12 squamous cell carcinoma of esophagus, PCR and SSCP analysis were performed. In only one of 12 tumors, complete deletion of p16 and p15 genes was detected. But in other 11 tumors, no abnormality could be detected. Besides to evaluate the prognostic significance of expression of p16 in patients of esophageal squamous cancer, immunohistochemical staining for p16 was performed. The patients with overexpression of p16 were significantly better prognosis than patients that was negative, and this result was opposite contrast with the result of cyclin D1.

Carcinoma, Squamous Cell↗
PubMed1995

Human platelet glycoproteins V and IX: mapping of two leucine-rich glycoprotein genes to chromosome 3 and analysis of structures.

Human platelet glycoproteins Ib alpha, Ib beta, V, and IX comprise an interrelated set of molecules (the Ib-V-IX system) that together form a surface adhesion receptor for the ligand, von Willebrand factor. To complete the primary structural characterization of the genes involved in this system, we have analyzed cosmid clones for both the glycoprotein V and IX genes and used these clones to localize the two genes by fluorescence in situ hybridization. Both genes were found on the long arm of chromosome 3, but at distinct sites, the GPV gene on 3 band q29 and the GP IX gene on 3 band q21. The transcriptional start site of the GPV gene was defined by "anchored" PCR and primer extension. The GPV gene contains two exons, the first consisting of approximately 37 bases and the second of approximately 3500 bases, interrupted by a single 958 base intron. The GPV transcript has multiple start sites spread over a twenty base region. The 5' flanking region of the GPV gene has a series of potential consensus regulatory elements including GATA, ets, and Sp-1 sites, similar to those found in other described megakaryocyte/platelet genes, including those of the Ib-V-IX system. In assessing the four Ib-V-IX genes as a group, all four have a simple, "intron-depleted" structure with the entire open reading frame of the mature polypeptide located within a single exon.(ABSTRACT TRUNCATED AT 250 WORDS)

Base Sequence↗
PubMed1995

Human platelet glycoprotein V: its role in enhancing expression of the glycoprotein Ib receptor.

Platelet adhesion to an injured blood vessel wall is a critical initiating step in hemostasis mediated by a four member receptor complex (glycoprotein Ib/V/IX) interacting with plasma von Willebrand factor (vWF). The function of the GPV subunit within this complex is presently undefined. To study the role of glycoprotein (GP) V within the GPIb receptor complex, we transfected the GPV subunit gene into a hematopoietic cell line that constitutively expresses the other three subunits (human erythroleukemia [HEL] cells). Using flow cytometry, we found transfected GPV was surface expressed in HEL cells; this, in turn, led to increased surface expression of the ligand-binding GPIb alpha and GPIX subunits. Radioligand binding assays showed that GPV-transfected HEL cells bound more vWF than their non- or mock-transfected counterparts. We employed confocal microscopy of GPV-transfected HEL cells to show that GPV colocalizes with GPIb alpha on the cell surface. These findings suggest that the GPV subunit plays a role within the GPIb receptor complex by enhancing Ib alpha surface expression.

Cell Membrane↗
PubMed1995

Morphological and biochemical changes in a hematopoietic cell line induced by jacalin, a lectin derived from Artocarpus integrifolia.

Treatment of the human erythroleukemia cell line K562 with the galactose-binding lectin, jacalin, results in rapid and profound alterations in the morphology and biochemistry of the cells. Within minutes of lectin addition, the cells adhere to the plastic tissue culture surface, and within hours, the cells spread on the surface, acquiring a monocyte-like appearance. Jacalin treatment results in elevated expression of CD61 (integrin beta 3) and CD14, a monocyte-associated cell surface antigen. These results suggest that jacalin treatment of K562 cells triggers intracellular events that result in differentiation along the monocyte lineage.

Amino Acid Sequence↗
PubMed1995

Familial nesidioblastosis in two sisters.

We herein present two female siblings with persistent hyperinsulinemic hypoglycemia in the neonatal period who were diagnosed as having familial nesidioblastosis. Despite both the administration of diazoxide and the intravenous infusion of glucose, one of the affected infants died of severe metabolic acidosis at about 1 month of age, before pancreatectomy could be performed. The other, in whom the disorder was diagnosed early, also failed to respond to conservative medical treatment and ultimately required a 99% pancreatectomy for control of hypoglycemia. A third female sibling was normal. The possibility of familial nesidioblastosis should thus be considered in the case of neonatal intractable hypoglycemia to ensure a prompt diagnosis and allow for early surgical intervention when indicated. The relevant literature on this life-threatening disorder is also reviewed.

Adenoma, Islet Cell↗
PubMed1995

A huge immature cervical teratoma in a newborn: report of a case.

A neonate with a large cervical mass was transferred to our hospital at 4 days of age. A computed tomography scan showed a contrast-enhanced solid mass with multiple cystic elements and fine calcification. Ultrasonography also revealed a predominantly solid mass with calcification, containing multiple cysts. These studies suggested a teratoma, but could not rule out a hemangioma. The tumor was removed on the 12th day of life. A pathological study revealed an immature teratoma that demonstrated fetal type cartilage and an immature neural tube. The operative complete removal of a cervical teratoma in neonates is recommended as soon as possible. The management of a pediatric cervical teratoma should also be similar to that of a sacrococcygeal teratoma. The incidence of cervical teratoma in all pediatric teratomas ranges from 2.3%-9.3% in the West, and from 1.6%-8.3% in Japan.

Cartilage↗
PubMed1995

Electrogastrography prior to and following total gastrectomy, subtotal gastrectomy, and gastric tube formation.

On electrogastrography (EGG) spectral analysis, an activity of 3 cycles per minute (cpm) is supposed to be specific for the stomach. After total or subtotal gastrectomy, the original site of the stomach is occupied mainly by the intestine. We attempted to determine if intestinal activity could be recorded in this region with EGG. Epigastric recordings were performed in patients prior and following gastrointestinal or control surgeries. Spectral analysis, using the maximal entropy method and ensemble means was applied to data analysis from these recordings. Preoperatively, the majority of the power peaks were found around 3, 6, and 11 cpm. The postprandial-to-fasting power ratio of all of these power peaks increased significantly postprandially (P < 0.05-0.01). Following total gastrectomy, the power peak around 3 cpm disappeared or was significantly diminished in amplitude (P < 0.05). The postoperative-to-preoperative power ratio ranged from 0.03 to 0.10 (P < 0.001-0.01). However, the power peak around 11 cpm did not significantly change prior to or following total gastrectomy, and the 11 cpm peak appeared relatively dominant. Simultaneous manometric studies in the Roux limb demonstrated a correlation between the power spectral frequency of EGG and manometry at 11 cpm. Therefore, the 11 cpm peak appeared to reflect jejunal or Roux limb electrical activity. The postoperative to preoperative power ratio for the 3 cpm also was significantly reduced following subtotal gastrectomy and gastric tube formation in patients in the postprandial state (P < 0.05-0.001).

Adult↗
PubMed1995

Analgesic and hypnotic effects of subanaesthetic concentrations of xenon in human volunteers: comparison with nitrous oxide.

The purpose of this study was to examine the effects of xenon and nitrous oxide in equipotent doses of 0.3 MAC on pain threshold and auditory response time in six healthy male volunteers. Compared with 100% oxygen inhalation, xenon and nitrous oxide significantly increased the pain threshold as measured by a radiant heat algometer. There was no significant difference in analgesic effects between xenon and nitrous oxide. Xenon significantly prolonged the response time to auditory stimuli compared with 100% oxygen, but nitrous oxide did not. The inhibitory effect of xenon on the auditory response time was significantly greater than that of nitrous oxide. The same six volunteers were studied to test if naloxone antagonized analgesia induced by xenon or nitrous oxide. The analgesic effects of xenon and nitrous oxide did not differ with or without naloxone.

Adult↗
PubMed1995

Transient expression of type I collagen in glomeruli with anti-Thy-1 antibody-induced mesangial proliferative lesions.

Glomerular expression of extracellular matrices at the protein and mRNA levels was examined in rats with mesangial proliferative glomerulonephritis induced by the intravenous administration of a monoclonal anti-rat Thy-1 antibody. In close association with the mesangial proliferative lesion, type I collagen was immunostained at day 8 but not demonstrated at day 28 in the glomeruli of the kidneys. Type I collagen mRNA expression prominently increased in the nephritic glomeruli at day 4, prior to the appearance of type I collagen protein. In addition, fibronectin expression was also elevated in the diseased glomeruli at both the protein and mRNA levels. These results indicated that glomerular, probably mesangial cells, change their phenotypes during this disease, to synthesize abnormal extracellular matrices that lead to the progression of glomerular sclerosis.

Animals↗
PubMed1995

Immunohistochemical quantitation for extracellular matrix proteins in rats with glomerulonephritis induced by monoclonal anti-Thy-1.1 antibody.

Extracellular matrix proteins (type I collagen and fibronectin) in frozen histologic sections of kidney cortex from rats with glomerulonephritis induced by a single intravenous administration of anti-Thy 1.1 antibody were quantified using an immunohistochemical micromethod. Type I collagen and fibronectin contents in renal cortex of rats with experimental glomerulonephritis (4.33 +/- 0.79 and 10.41 +/- 2.01 microgram/mg of total protein, respectively) were 262% and 151%, respectively, higher than in control rats given normal mouse IgG (1.65 +/- 0.16 and 6.88 +/- 0.95 microgram/mg, respectively; p < 0.01 in each case). In the glomerulonephritic rats, the increase in the contents of extracellular matrix proteins, especially type I collagen, correlated with increasing glomeruli with expansion of mesangial areas. The increase in type I collagen content correlated well with increasing urinary protein excretion and blood urea nitrogen and serum total cholesterol levels (r = 0.851, 0.812, and 0.837, respectively; p < 0.05 in each case). The decrease in creatinine clearance correlated with increasing content of type I collagen (r = 0.781; p < 0.05). The immunohistochemical micromethod may make it possible to evaluate the histopathological diagnosis of mesangial proliferative glomerulonephritis quantitatively.

Animals↗