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Biomedical subjects

H Kawakami

Publications and source records attributed to H Kawakami.

At least 19 recordsLinked to original sources
PubMed1992

Changes in lectin binding patterns of Leydig cells during fetal and postnatal development in mice.

Changes in the lectin binding of mouse Leydig cells during fetal and postnatal development were examined by light- and electron-microscopy using eight different biotinylated lectins (ConA, WGA, RCA-I, UEA-I, GS-I, PNA, SBA and GS-II). At the light-microscopic level, ConA, WGA, RCA-I, UEA-I and GS-I showed the same binding pattern in which all five lectins bound to the plasma membrane and cytoplasm of Leydig cells from the 13th day post coitum (p.c.) to the 8th postnatal week. PNA, SBA and GS-II reactions were positive in the plasma membrane and cytoplasm of Leydig cells from the 13th day p.c. to 15th day post partum (p.p.) but disappeared completely by day 20. At the electron-microscopic level, gold particles representing the GS-I or GS-II binding sites were distributed primarily along the cell surface membrane, including that of microvilli, as well as in the cytoplasm. These results indicate that certain glycoconjugates bearing D-galactose, N-acetyl-D-galactosamine, and N-acetyl-D-glucosamine residues are expressed on the cell surface and in the cytoplasm of Leydig cells during the period from the 13th day p.c. to around the 20th day p.p. The results suggest that these glycoconjugates might play some role in modulating hormone-receptor interaction in the Leydig cells before the 20th day. Furthermore, these results may indicate that sugar residues expressed on the cell surface and in the cytoplasm of Leydig cells are different from those in the fetal-neonatal and adult phases.

Animals↗
PubMed1992

Changes in expression of the endogenous beta-galactoside-binding 14-kDa lectin of chick embryonic skin during epidermal differentiation.

Changes in the expression pattern of the gene for the endogenous beta-galactoside-binding 14-kDa lectin of chick embryo were examined immunohistochemically during epidermal differentiation in vivo and in vitro with special reference to detailed localization of the 14-kDa lectin. The gene expression was visualized by the HRP-staining method following in situ hybridization, in which sulfonated cDNA was employed as a probe. The 14-kDa lectin gene expression (mRNA) was detected mainly in the intermediate layer of the epidermis: it was faint in 13-day-old embryos, gradually increased in intensity during epidermal differentiation, and became intensely positive in 17-day-old embryo. The expression of the gene in skin explants was suppressed by vitamin A, which induces mucous metaplasia of the epidermis in vitro. The anti-14-kDa lectin reaction was positive mainly in the intermediate layer of the differentiating epidermis, coinciding chronologically with expression of the gene at the light microscopic level. Immunoelectron microscopy revealed that the positive reaction was primarily localized in desmosomes, in tonofilament bundles anchored to the desmosomes, along the outer surface of the plasma membrane, and in the intercellular space. Essentially the same staining pattern was observed in differentiating epidermis in vitro. The positive reaction was markedly reduced in the epidermis in which differentiation had been suppressed in vitro by the addition of vitamin A.

Animals↗
PubMed1992

HLAs and genes in Japanese patients with multiple sclerosis: evidence for increased frequencies of HLA-Cw3, HLA-DR2, and HLA-DQB1*0602.

The distribution of HLA-A, B, C, DR and DRB1, DQB1, DPB1 alleles was studied in 60 Japanese patients with clinically definite multiple sclerosis (MS) using serologic and genomic analysis. We found significant associations with HLA-Cw3 (p = 0.002, pc = 0.012, RR = 3.2), DR2 (p = 0.007, RR = 2.6), and DQB1*0602 (p = 0.04, RR = 4.0) in Japanese patients for the first time. The combined presence of Cw3 and DR2 gave a higher risk than each antigen alone. The reported increase in the frequency of DPw4 in Japanese MS patients [12] could not be confirmed by our genomic study. The frequencies of all of the residues in each variable region of the amino acid sequences of DQ beta and DP beta chains were not different between the MS patients and the controls. These results suggest that MS susceptibility may result from polygenic influences and from the presence of environmental factors.

Alleles↗
PubMed1992

Structural organization and expression of the gene for bovine myosin I heavy chain.

Brush border myosin I heavy chain (MIHC), known previously as the brush border 110-kDa protein, contains an amino-terminal sequence which is highly homologous to the globular head domain of conventional myosin II heavy chain (MIIHC). The carboxyl-terminal sequence of MIHC completely diverges from that of MIIHC and functions as calmodulin-binding and membrane-interaction sites. In this investigation, we determined the structural organization of the bovine MIHC by isolating a set of genomic segments containing the whole MIHC gene. The bovine MIHC gene is 26 kilobase pairs long and consists of 28 exons. At the homologous amino-terminal portion of MIHC, many introns are located at positions equivalent to those of the rat MIIHC gene and the amoeba MIHC gene. At the carboxyl-terminal sequence of MIHC, the putative calmodulin-binding and membrane-interacting domains are specified by discrete sets of exons. These findings support the view that the amino-terminal head portions of MIHC and MIIHC evolved from a common ancestral origin and also that the MIHC protein was generated as a result of fusion of discrete genomic segments encoding different functional and structural protein domains. Analysis of tissue expression of the MIHC mRNA was also extended in this investigation, and the results indicated that this mRNA is expressed in some tissues other than the intestines.

Amino Acid Sequence↗
PubMed1992

Involvement of actin filaments in mouse testicular cord organization in vivo and in vitro.

Involvement of actin filaments in mouse fetal testicular differentiation was examined in vivo and in vitro. During testicular cord formation in vivo, actin filaments accumulated in the basal cytoplasm of Sertoli cells. Addition of cytochalasin D (CD) to organ cultures of undifferentiated gonadal primordia significantly inhibited testicular cord formation. In brief, treatment with 25 ng/ml CD induced the formation of slender testicular cords, and treatment with 50 ng/ml largely inhibited cord formation in the explants. However, development and growth of the testicular parenchyma and Leydig cell differentiation occurred in the presence of CD. By electron microscopic and immunohistochemical examinations, it became clear that CD also affected formation of the basal lamina and accumulation of vimentin filaments in Sertoli cells. On the other hand, treatment with colcemid at 12.5 or 15 ng/ml prevented growth of the testicular parenchyma and development of interstitial regions. Interestingly, testicular cords formed under this condition. These results indicate that the basal actin filaments of Sertoli cells may play an important role in testicular cord formation, especially Sertoli cell polarization. Cell mitosis and/or microtubules, on the other hand, may not be directly involved in this process.

Actins↗
PubMed1992

Vibrio cholerae non-O1 isolated from ayu fish (Plecoglossus altivelis) in Japan.

A fish pathogen, Vibrio cholerae non-O1, was isolated from diseased ayu fish (Plecoglossus altivelis) collected from rivers in eight prefectural districts of Japan. This organism was found to have biochemical characteristics similar to those of V. cholerae non-O1, except that our isolates were negative for ornithine decarboxylase. Antiserum against an ayu isolate did not agglutinate with the majority of environmental V. cholerae non-O1 isolates, but a major O antigen was common among the ayu isolates. All strains were hemolytic to sheep erythrocytes, and oral administration of culture supernatants induced fluid accumulation in suckling mice. However, the crude toxin was not lethal to adult mice, and no cholera toxin-like enterotoxins were detected.

Agglutination Tests↗
PubMed1992

Changes in intracellular and cell surface localization of Le(x) epitope during germ cell differentiation in fetal mice.

Changes in the intracellular and cell surface localization of Lewis x (Le(x)) determinants in germ cells during fetal development in mice were examined by light and electron microscopy. Light microscopically, in undifferentiated gonads on day 12 post coitum (p.c.), the anti-Le(x) monoclonal antibody (MAb) was specifically bound to the plasma membranes and to the cytoplasmic granule-like structures of germ cells. In the testes on day 13 p.c., most of the germ cells were enclosed within the testicular cords and showed an MAb-positive reaction which was restricted mainly to the cytoplasmic granule-like structures. The reaction on the plasma membranes almost disappeared. On the other hand, the ectopic germ cells still showed a positive reaction on their plasma membranes. In the ovaries on day 13 p.c., the germ cells also exhibited positive reactions both on the plasma membranes and on the granule-like structures. Immunoelectron microscopic observations agreed well with these light microscopic observations in such a way that both the plasma membranes and the "small dense bodies" (SDB) were positive in undifferentiated gonads on day 12 p.c. In the germ cells organized into the testicular cords, the reaction to anti-Le(x) MAb became restricted to the SDB. These results may indicate that such intracellular changes in Le(x) determinants during germ cell differentiation are associated with the enclosure of germ cells within the testicular cords.

Animals↗
PubMed1992

[Effect of AS-4370 on gastric motility in patients with diabetic autonomic neuropathy].

Delayed gastric emptying in diabetic patients occurs with progress of automatic neuropathy as one late complication. Delayed emptying is deeply correlated with poor glycemic control, due to imbalance between nutrients absorption and effect of exogenous insulin. AS-4370 is a newly developed prokinetic agent which has been reported to selectively activate motility of the upper gastrointestinal tract through enhancing acetylcholine release from nerve terminals within the enteric mural plexus. In this study, we evaluated the effect of AS-4370 on gastric motility in diabetic patients with autonomic neuropathy. Eight diabetic patients with autonomic neuropathy (3 males and 5 females) with mean age of 56 years old (range 29-66) participated to this study after giving written informed consent. Gastric motility was evaluated by gastric emptying and electrogastrography. Gastric emptying study was done using 99mTc-Tin colloid labeled omelet meal served with 2 slices of toast and 200 ml of milk. Electrogastrography was recorded from epigastric skin surface, for 30 minutes before and after meal each. AS-4370, 7.5 mg tid, was given for four weeks after basal recording of gastric motility studies. Following the 4-week treatment with AS-4370, gastric motility studies were repeated. For the motility studies after medication, drug was given 30 minutes before test meal. Gastric retention rate at 150 minutes in all patients were over 45% of upper limit of normal range in basal study with mean value of 69 +/- 5%, which decreased significantly to 52 +/- 5%, with AS-4370 treatment (p < 0.01). Gastric emptying speed, another parameter for gastric emptying also improved with medication.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Glomerular/tubular mixed-type proteinuria in a 3-year-old boy with mental retardation and hyperkinesis.

A 3-year-old boy with mixed glomerular/tubular proteinuria, mental retardation, and hyperkinesis is described. The proteinuria was discovered at the age of 3 years on urinary mass screening. Most of the urinary protein consisted of albumin, accompanied by increases in low molecular weight proteins, including beta 2-microglobulin and alpha 1-microglobulin. Mixed glomerular/tubular proteinuria is known to be caused by the following conditions: chronic renal failure, chronic pyelonephritis, cadmium poisoning, tubulointerstitial nephritis of various etiologies, and after strenuous, short-term, exhaustive exercise. The present patient did not display any of these disorders or conditions.

Child, Preschool↗
PubMed1992

Urine concentration adjustment with a dipstick is dispensable for urinary beta 2-microglobulin screening in children.

Single voided urine was collected from 1,699 3-year-olds. The urinary beta 2-microglobulin levels (microgram/l) were measured by ELISA. The frequency of the levels was distributed with a wide base on the right side, even after logarithmic transformation. The upper limits of the 98% confidence interval were 660 micrograms/l for boys and 690 micrograms/l for girls. The values adjusted to a specific gravity of 1,020 in a total of 1,468 urine samples, of which the specific gravity was examined with Nephrosticks L, from 746 boys and 722 girls were similarly distributed, and the upper limits of the 98% confidence interval were 550 micrograms/l for boys and 530 micrograms/l for girls. There was no significant sex-related difference. Of the 14 children who had adjusted beta 2-microglobulin values above the adjusted upper limit of the 98% confidence interval, 11 (79%) had actual levels above the actual upper limit of the 98% confidence interval, 11 (79%) had actual levels above the actual upper limit of the 98% confidence interval. Finally, 2 children (one boy and one girl) proved to have renal disease. In these 2, both the actual and adjusted values exceeded the respective upper limits of the 99% confidence interval. Concentration adjustment appears to be dispensable in the screening for renal disease. In practice, 600 micrograms/l would serve as an actual cut-off level for both sexes with safety.

Age Factors↗
PubMed1992

Neonatal Legionnaires' disease. Histopathological findings in an autopsied neonate.

A neonatal case of legionnaires' disease (LD) is reported. A male neonate was admitted to our hospital with high fever and dyspnea, which had started 5 days after birth, and died due to severe pneumonia at 10 days old. An autopsy revealed small areas of granular consolidation scattered diffusely in the bilateral lungs. Microscopic examination of the lungs showed mainly lobularly distributed pneumonia. Extensive exudation of macrophages and neutrophils was observed in the terminal respiratory tract and alveolar spaces. Warthin-Starry and Gimenez staining and electron microscopy detected many coccobacilli in the cytoplasm of exudated macrophages and neutrophils. Immunofluorescence staining using antiserum against Legionella pneumophila, serogroup 1, showed a positive reaction. Bacteriological examinations of aspirate from the respiratory tract and autopsied lung tissue confirmed the presence of Legionella pneumophila, serogroup 1. Extrapulmonary LD was not detected. LD usually affects aged or immunocompromised hosts, but there was no evidence of immune deficiency in this case. Pediatric cases of LD have rarely been reported, and a survey of the literature revealed few neonatal cases. The present case may alert neonatologists and other medical personnel to the possibility of neonatal LD infection.

Autopsy↗
PubMed1992

[Gastrointestinal motility and autonomic nerve dysfunction].

Gastrointestinal motility is greatly influenced by both the autonomic nervous system (ANS) and the enteric nervous system (ENS). Dysfunction of ANS and/or ENS produces various kinds of dysmotility from the esophagus to the colon. Generalized autonomic dysfunction, often seen in diabetics, causes abnormal peristaltic waves in the esophagus, abnormal electrical activity of the stomach, delayed gastric emptying and delayed intestinal transit. Localized disorders of the enteric nervous system is seen in patients with achalasia and Hirschsprung's diseases. Functional disorders, without evidence of organic disorders, like non-cardiac chest pain, non-ulcer dyspepsia, irritable bowel syndrome, can be partly caused by abnormal function of autonomic nervous system.

Autonomic Nervous System↗
PubMed1991

Effect of tunicamycin, an inhibitor of protein glycosylation, on testicular cord organization in fetal mouse gonadal explants in vitro.

The effect of tunicamycin (TM) on testicular cord organization in the fetal mouse was examined in vitro at light and electron microscopic levels, with special reference to the glycoprotein functions during Sertoli cell differentiation. In testicular explants treated with TM, testicular cord organization was inhibited. TM treatment affected basal lamina formation by Sertoli cells, resulting in a discontinuous basal lamina or none at all in certain areas. The disorganized Sertoli cells were amorphous in shape, exhibited poor epithelial polarity, and were irregularly arranged in the testicular parenchyma. Extracellular matrix and collagen fibers were often observed in the intercellular spaces between the disorganized Sertoli cells. Lectin histochemical observation revealed that the number of wheat germ agglutinin binding sites on the plasma membrane and basal lamina of disorganized Sertoli cells was significantly decreased by TM treatment. However, junctions were normally observed in the plasma membrane between disorganized Sertoli cells. Leydig cells showed a normal differentiation in the testicular parenchyma in the presence of TM. These observations suggest that basal lamina formation of Sertoli cells and/or the expression of their cell surface glycoconjugates may be crucial for the establishment of Sertoli cell polarity and/or the Sertoli-Sertoli cell interactions required for proper testicular cord formation. Sertoli cell organization into testicular cords and Leydig cell differentiation may be controlled by different regulatory mechanisms.

Animals↗
PubMed1991

A unique pattern of astrocytosis in the primary motor area in amyotrophic lateral sclerosis.

We examined the primary motor area (PMA, Brodmann area 4) from 23 cases of adult-onset sporadic amyotrophic lateral sclerosis (ALS) with immunocytochemistry using anti-glial fibrillary acidic protein antibody. There was astrocytosis in the middle of the pyramidal cell layer in all cases except for one that did not present any upper motor neuron signs clinically. The astrocytosis was characterized by multiple clusters of astrocytes, some of which showed a close association with macrophages. In about a half of the cases, these multiple clusters of astrocytes became confluent and presented as a laminar astrocytosis in the middle of the pyramidal cell layer. Our studies demonstrate a unique pattern of astrocytosis in the PMA in ALS. This pattern of astrocytosis may be useful not only for diagnostic purposes, but also for a better understanding of the pathological process involving the PMA in ALS.

Amyotrophic Lateral Sclerosis↗
PubMed1991

Frequency of elevated urinary beta 2-microglobulin levels in relatives of patients with asymptomatic low-molecular-weight proteinuria.

We studied urinary beta 2-microglobulin levels in a total of 29 apparently healthy relatives (aged 0.8-70 years) of 8 male patients with asymptomatic low-molecular-weight proteinuria in six families. The frequency of levels above the age- and sex-associated 95% confidence limit was 7 of 29 (24%), 4 of 12 (33%) in first-degree relatives, 2 of 6 (33%) fathers, and 2 of 6 (33%) mothers. These frequencies were significantly above those in the general population (P less than 0.01, by a normal distribution test, a binomial distribution, and Poisson distribution test for the sample proportion). The increased frequency in fathers argues against an X-linked pattern of inheritance for this entity, suggesting that there is heterogeneity in the inheritance.

Adolescent↗
PubMed1991

Development of AChE-positive, NA-containing and VIP- and NPY-immunoreactive nerves in the major cerebral arteries of the rat.

The development of cerebrovascular nerves containing noradrenaline (NA), acetylcholinesterase (AChE), neuropeptide Y (NPY), and vasoactive intestinal polypeptide (VIP) was studied in rats from before birth to adulthood. All these nerves entered the cranial cavity along the cerebral carotid, internal ethmoidal, and vertebral arteries during the early stages of development, but the subsequent growth and distribution of NA-containing and NPY-immunoreactive (IR) nerves differed greatly from that of AChE-positive and VIP-IR nerves. NA-containing and NPY-IR nerves extended rapidly from the cerebral carotid artery and spread over all the major arteries of the internal carotid system by postnatal day 3, as well as descending the posterior ramus of the cerebral carotid to mingle with nerves from the vertebral artery around the mid-basilar artery by day 5. AChE-positive and VIP-IR nerves from the internal ethmoidal artery covered the whole internal carotid system during the first postnatal week, and projected to the upper basilar artery after the second week, while those from the cerebral carotid artery remained limited to the middle cerebral artery throughout development. By day 21, all major arteries of the internal carotid system had dense plexuses of the four nerve types that were similar to those observed in adult rats. The vertebrobasilar system also had a well-organized network of NA-containing and NPY-IR nerves, but only a poor supply of AChE-positive and VIP-IR nerves. Even on day 30, the latter two nerve types were sometimes absent from the middle to caudal basilar artery, owing to a lack of interdigitation by nerves from the internal ethmoidal and vertebral arteries.

Acetylcholinesterase↗