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Biomedical subjects

N Goto

Publications and source records attributed to N Goto.

At least 109 records · Page 6Linked to original sources
PubMed1998

Histopathological studies of senile plaques and cerebral amyloidosis in cynomolgus monkeys.

Senile plaques (SPs) and cerebral amyloid angiopathy (CAA), pathological hallmarks of Alzheimer's disease, have not been thoroughly investigated histopathologically in nonhuman primates. To determine the onset age and histopathological characteristics of SPs and CAA, we examined the brains of 64 cynomolgus monkeys (Macaca fascicularis) from 2 to 35 years old. Mature (classical and primitive) plaques appeared in 16 out of 25 monkeys that were >20 years old. Moreover, mature plaques were observed more frequently than diffuse plaques and were located in the temporal cortex of the superior or inferior gyri and amygdala. Diffuse plaques in contrast to mature plaques did not show definite tendencies in onset age and distribution. CAA appeared in more than 22-year-old monkeys in 10 out of 16 animals and was frequently observed in capillaries and often found adjoining mature plaques. During immunohistochemical examination, an antiserum for amyloid beta protein (A beta) 1-40 could detect all SPs, whereas a monoclonal antibody for A beta 8-17 could not detect any diffuse plaques and only one third of the primitive plaques. As for CAA, the polyclonal antiserum was more sensitive than the monoclonal antibody. The present study describes the histopathological features of SPs and CAA in old cynomolgus monkeys.

Aging↗
PubMed1998

[Antibody response of inactivated influenza vaccine in the elderly].

The antibody responses of 31 elderly persons (11 males and 20 females, mean 82.2 years) and 23 adults (mean 40.7 years) to inactivated influenza vaccine were studied. Participants were given twice the influenza vaccine containing A/Yamagata/32/89, A/Kitakyusyu/159/93, and B/ Mie/1/93. Serum specimens were obtained before vaccination, and 2 weeks and 3 months after the second vaccination. Antibody to influenza was determined by hemagglutination inhibition test (HI). The rates of fourfold or greater increases of HI antibody against the A/Yamagata, A/ Kitakyusyu, and B/Mie were 96.8%, 100%, and 74.2%, and there was no significant difference of the rates of fourfold or greater increases between elderly persons and adults. The rates of possession of HI antibody more than 128 in titer after vaccination were significantly higher than those of HI antibody before vaccination, and were maintained at high levels up to three months after the second vaccination. These results suggest that antibody response to the inactivated influenza vaccine is satisfactory in the elderly.

Adult↗
PubMed1998

Respiratory viral infections in the elderly in a nursing home.

The purpose of this study was to investigate what viruses infiltrate into our nursing home, assess the related clinical symptoms in elderly subjects, and compare the incidence of infections with those in the general community. Between July 1994 and June 1995, 40 elderly persons dwelling in the nursing home were evaluated by clinical observation, serologic analysis, and viral culture of samples to determine the presence of viruses. Enteroviruses and herpes simplex I virus could be isolated from asymptomatic elderly subjects. Individuals with influenza B virus and RSV infections diagnosed by serology did have clinical symptoms. The prevalence of both influenza B virus and enteroviruses was related to that of such viruses in the general community. Our data suggest that respiratory viruses are readily transmitted from the community to nursing home residents.

Aged↗
PubMed1998

Unmyelinated nerve fiber analysis of the human abducent nerve.

Unmyelinated nerve fibers of the abducent nerve have occasionally been observed with electron microscopes, but, to our knowledge, they have never been evaluated from the morphometric point of view. We analyzed the aging process of the unmyelinated nerve fibers in the human abducent nerve with the help of a new staining method suitable for morphometric research on the nervous system. We studied numbers and transverse areas of unmyelinated fibers of the abducent nerve in 10 cadavers. Our findings were that (1) these fibers were distributed diffusely, (2) their number decreased with age, and (3) the mean transverse area did not change with age. Most of the unmyelinated axons were thinner than the myelinated axons. These results may be important for analysis of clinical signs in relation to aging and ophthalmologic functions.

Abducens Nerve↗
PubMed1998

Morphometric nerve fiber analysis and aging process of the human abducent nerve.

Myelinated nerve fibers of the human abducent nerve were analyzed with a new staining method that permits simultaneous observation of the axon and surrounding myelin sheath. The following equipment was employed for the measurements: an image-analyzing digitizer, a microscope equipped with a drawing tube (or camera lucida), and a computer for data storage and statistical analysis. The numbers, transverse areas, and circularity ratios of axons were measured in 10 human abducent nerves. The average number was 1,997 with a definite decrease with age, and the average area was 3.90 micron 2.

Abducens Nerve↗
PubMed1998

[Case report of the right-sided aortic arch (N-type): new classification based on macroscopic observations].

We report on a case with unusual origin of the left subclavian artery, so-called N-type found in a 62-year-old Japanese male in 1995. We took the opportunity in proposing for a new classification based on macroscopic observations. In the present observation, the following arteries branched off from the aortic arch in the order of the left common carotid, the right common carotid, the right subclavian and the left subclavian arteries. There was an aortic diverticum between the left subclavian artery and the dissending aorta. The left subclavian artery passed between the esophagus and the thoracic vertebrae. The arterial ligament connected the left pulmonary artery with the aortic diverticulum of the left subclavian artery. According to our observations, the arch of the aorta, descending aorta, aortic diverticulum of the left subclavian artery, arterial ligament and pulmonary artery joined to foam an incomplete vascular ring around the trachea and esophagus. This case can be classified into the N-type according to classifications by Adachi (1928), Williams (1932, 1935) and Nakagawa (1939). This may be the 22nd report in Japan regarding this kind of combined variations. Our classification also includes those by Takemura (1990) and Edwards (1964). An explanation of the new classification is described below and is also shown in Fig. 3. Abbreviations for classification types have been arranged in the order of the relation to the esophagus, the mirror-image subtyping of the Takemura's classification and the location of the arterial ligament. For example, type Na1 (present case) represents the left subclavian artery passing behind the esophagus, mirror-image to the Takemura's G-type, and left arterial ligament.

Aorta, Thoracic↗
PubMed1997

Development of the human principal sensory trigeminal nucleus: a morphometric analysis.

The anatomical development of the principal sensory trigeminal nucleus was assessed with morphometric features using serial celloidin sections of 15 human brains, including 12 brains obtained from fetuses and neonates. A microscope and an optical electronic planimeter combined with a computer were employed for morphometric measurements of columnar areas, neuronal numbers, neuronal areas and neuronal perimeters to statistically analyze and evaluate the development of neuronal densities, neuropil indexes and circularity ratios. We could not detect the principal sensory trigeminal nucleus in the specimen of 12 gestational weeks (GW). Microscopic observation disclosed that the fetal principal sensory trigeminal neurons approached those of the adult around 33 GW in terms of cell arrangements, amounts of Nissl bodies and morphology of neurons. Our morphometric analysis showed that the columnar volume, the neuronal area and the neuropil index increased with gestational age. The neuronal density decreased with gestational age, especially from 16 to 32 GW. Comparing the neuronal area with the columnar volume, it developed before the columnar volume during the fetal period. The neurons of the principal sensory trigeminal nucleus matured around 33 GW under microscopic observation and in terms of the distribution of neuronal areas. The development of the neuropil may accelerate after individual neurons of principal sensory trigeminal nucleus mature.

Adolescent↗
PubMed1997

Development of the human lateral vestibular nucleus: a morphometric evaluation.

The development of the human lateral vestibular nucleus was studied on serial sections of the brain of 8 fetuses and neonates at 12-40 weeks of gestation, an infant at 2 months of age and an adult of 63 years using a microscope with a drawing tube and an image-analysing computer system. A morphometric analysis revealed that the lateral vestibular nucleus, whose neurons were distinguished from glia after 16 weeks of gestation, divided cytoarchitectonically into the medial and the lateral subnuclei at 21 weeks of gestation onwards, and showed the moderate development in terms of the columnar length and volume, neuronal size and neuropil.

Female↗
PubMed1997

Phylogenetic position of the mitochondrion-lacking protozoan Trichomonas tenax, based on amino acid sequences of elongation factors 1alpha and 2.

Major parts of amino-acid-coding regions of elongation factor (EF)-1alpha and EF-2 in Trichomonas tenax were amplified by PCR from total genomic DNA and the products were cloned into a plasmid vector, pGEM-T. The three clones from each of the products of the EF-1alpha and EF-2 were isolated and sequenced. The insert DNAs of the clones containing EF-1alpha coding regions were each 1,185 bp long with the same nucleotide sequence and contained 53.1% of G + C nucleotides. Those of the clones containing EF-2 coding regions had two different sequences; one was 2,283 bp long and the other was 2,286 bp long, and their G + C contents were 52.5 and 52.9%, respectively. The copy numbers of the EF-1alpha and EF-2 gene per chromosome were estimated as four and two, respectively. The deduced amino acid sequences obtained by the conceptual translation were 395 residues from EF-1alpha and 761 and 762 residues from the EF-2s. The sequences were aligned with the other eukaryotic and archaebacterial EF-1alphas and EF-2s, respectively. The phylogenetic position of T. tenax was inferred by the maximum likelihood (ML) method using the EF-1alpha and EF-2 data sets. The EF-1alpha analysis suggested that three mitochondrion-lacking protozoa, Glugea plecoglossi, Giardia lamblia, and T. tenax, respectively, diverge in this order in the very early phase of eukaryotic evolution. The EF-2 analysis also supported the divergence of T. tenax to be immediately next to G. lamblia.

Amino Acid Sequence↗
PubMed1997

Three-dimensional structure of the human cerebellar dentate nucleus: a computerized reconstruction study.

To explore the regional differences in neuronal cytoarchitecture of human dentate nucleus, we examined first the three-dimensional structure of this nucleus with a computerized reconstruction technique, after making serial sections of the brain in seven fetuses aged from 20 to 39 weeks of gestation (WG), an infant (1-month-old) and two adults (22- and 85-year-old). The surface was broadly smooth at 20-22 weeks, but primary gyri or fissures were noticed in the rostral half of the lateral surface, earliest in its dorsal region. A small cavity (the hilus nuclei dentati) was situated in the middle of the medial surface, with four distinct margins. A great progress in gyration was noted after 22 weeks: gyri were observed over the entire surface by 28-29 weeks. Gyri were thicker in the caudal half than the rostral half both in the lateral and the medial surfaces. At this stage, the rostral margin of the hilus was partially cut off and the hilus was elongated toward the rostral tip, but its relative size appeared to be grossly equal to that at 22 weeks. The hilus began to open wider and wider after 30 weeks. Subdivision of the human dentate nucleus into two different parts (the smaller microgyric rostral part and the larger macrogyric caudal part) was accomplished by 35 weeks. We have previously, using morphometric approaches, reported that a vulnerable (or critical) period may exist during 20-30 weeks in the fetal development of the dentate nucleus. It is possible that this special ten weeks of mid-gestation may be coincident with the time of extensive growth in gyration for this nucleus. It will be necessary to sample the neurons independently from at least two different parts, as described above, to design further microscopic studies on the regional differences or on other cytological investigations.

Adult↗
PubMed1997

In vitro inhibition of caries around a resin composite restoration containing antibacterial filler.

Class V cavities were prepared and restored with resin composite containing antibacterial filler powder (Apacider-AW, Ap-AW) using experimental restorations. The restored teeth were incubated in vitro with the cariogenic bacteria Streptococcus mutans IFO 13955. Ground sections were then prepared and examined using macrophotography. Lesions of the outer and inner wall were noted, and the depths of which the lesions penetrated were measured. We found that, in restorations containing 1-5 wt% Ap-AW, caries penetrated the marginal area, while in restorations containing 10 wt% Ap-AW the margin remained free of caries out to a distance of about 1.1 and 1.8 mm on the occlusal and gingival sides, respectively.

Biocompatible Materials↗
PubMed1997

Specific and sensitive detection of Trichomonas tenax by the polymerase chain reaction.

A polymerase chain reaction (PCR) protocol was developed for specific detection of Trichomonas tenax by using a pair of primers designed for its 18S rRNA gene. The detection was specific for T. tenax, since no amplification was detected with DNAs from Trichomonas vaginalis, which belongs to the same genus as T. tenax, in addition to various species of oral protists, fungi and bacteria, and human leukocytes. This method had a detection limit of 100 fg for T. tenax genomic DNA and could detect T. tenax cells in dental plaque at a concentration of as low as 5 cells per PCR mixture. Direct detection from clinical dental plaque samples was also possible; therefore, the present PCR procedure could provide a simple and rapid detection method of T. tenax in dental plaque.

Animals↗
PubMed1997

Role of glucocorticoid in the upregulation of type I interleukin-1 receptor mRNA expression in hepatocytes of endotoxin-administrated mice.

The interleukin-1 (IL-1) signal is transduced through type I IL-1 receptor (IL-1RI). We have recently reported that lipopolysaccharide (LPS) upregulated IL-1RI mRNA expression in mouse liver in vivo and that IL-1 and IL-6 directly upregulated IL-1RI mRNA expression in primary cultured mouse hepatocytes. Glucocorticoid (GC) has been reported to increase IL-1 binding to the cell surface and the expression level of IL-1R mRNA in a variety of cell types. As serum GC level is elevated in an inflammatory response, we evaluated the role of GC in LPS-induced upregulation of IL-1RI mRNA in the mouse liver. When LPS was administered to adrenalectomized (ADX) mice, IL-1RI mRNA was upregulated at a level comparable to those of untreated or sham-operated mice. A high dose of dexamethasone (Dex), however, caused upregulation of the mRNA. When primary cultured mouse hepatocytes were treated with Dex, only a weak upregulation of IL-1RI mRNA was observed. However, Dex in combination with IL-1 or IL-6 markedly enhanced the IL-1RI mRNA expression. A marked upregulation of the mRNA was also induced by treatment with a combination of IL-1 and IL-6 in the absence of Dex, reflecting the observation in ADX mice. These results suggest that the upregulation of IL-1RI mRNA in response to LPS is induced by the interaction of IL-1 and IL-6 and that GC augments their effect.

Adrenal Glands↗
PubMed1997

Adjuvanticity of an ornithine-containing lipid of Flavobacterium meningosepticum as a candidate vaccine adjuvant.

Ornithine-containing lipids (OrnL) extracted from Flavobacterium meningosepticum have been reported to have various biological activities such as B-cell mitogenicity and macrophage activation to generate interleukin-1 and prostaglandin E2. We, using ovalbumin (OVA) as an antigen, evaluated the adjuvant activity of OrnL as an immunological adjuvant in BALB/c mice. OrnL showed the function of forming liposome-like vesicles retaining biological activities when prepared as either small unilamellar or dehydration-rehydration vesicles. Although OrnL was not shown to have enough entrapping efficacy for use as a vaccine adjuvant, phosphatidylglycerol (PG) and cholesterol (CHOL) added to stabilize the vesicle membrane increased the entrapping efficacy to the same extent as that of conventional liposomes. Furthermore, the stabilized OrnL vesicles tolerated centrifugation to remove non-entrapped antigens. Completely antigen-entrapped OrnL vesicles including Pg and CHOL induced a significantly greater enhancement of IgG antibody production than did aluminum hydroxide gel in BALB/c mice from week 6. These results indicate that OrnL can be utilized as an immunological adjuvant for vaccines.

Adjuvants, Immunologic↗
PubMed1997

Case report: congenital absence of the portal vein associated with nodular hyperplasia in the liver.

Congenital absence of the terminal portion of the portal vein with visceral venous return to the suprahepatic inferior vena cava, a rare malformation, was demonstrated in an 18-year-old Japanese woman. She had nodular hyperplasia in the liver and a non-functioning pancreatic endocrine tumour. It is generally believed that reduction of portal venous flow causes atrophic changes and, subsequently, nodular hyperplasia occurs in a well-perfused area in the liver. However, the liver was not perfused by the portal vein in this case. It is suggested that nodular hyperplasia can occur without portal blood flow.

Adolescent↗
PubMed1997

Amyloid deposits in the gastrointestinal tract of aging dogs.

Pathologic features, immunohistochemical characteristics, and incidence of gastrointestinal amyloid deposition were investigated in 78 canine necropsies, including 43 males and 35 females ranging from 2 months to 20 years of age. In 31 of 78 dogs, amyloid protein was accumulated in or around vessel walls located in submucosal and muscular layers of the alimentary tract and mesenteric tissues. These deposits did not seem to affect the function(s) of the digestive tract histologically. The deposits showed congophilia and green birefringence under polarized microscopy. Transmission electron microscopy revealed randomly arranged amyloid fibrils 6-10 nm in diameter around a blood vessel. Congophilia was retained even after oxidation with potassium permanganate, suggesting that this protein is not the AA form of amyloid. Although immunohistochemical studies were performed using antibodies to canine amyloid apolipoprotein AI and synthetic human beta amyloid peptide, the immunochemical nature of the protein was not determined. The mean ages of both male and female dogs with gastrointestinal amyloid deposition were higher than those of their normal counterparts (P < 0.001), and the incidence of deposition in elderly dogs was higher than that in young dogs (P < 0.005). However, there was no sex predilection with respect to both the mean age of the dogs with deposition and the incidence of occurrence. The mechanism(s) and importance of this form of amyloid deposition remain unclear.

Aging↗