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Biomedical subjects

N Wada

Publications and source records attributed to N Wada.

At least 181 records · Page 10Linked to original sources
PubMed1994

Anatomical structure and action of the tail muscles in the cat.

Anatomical structure and movements of tail muscles were studied in 12 adult cats. Tail muscles mainly consisted of the following 6 muscles on both sides, M. sacrocaudalis dorsalis medialis (SDM), M. sacrocaudalis dorsalis lateralis (SDL), M. coccygeus lateralis (CL), M. coccygeus medialis (CM), M. sacrocaudalis ventralis lateralis (SVL) and M. sacrocaudalis ventralis medialis (SVM). Experiments by electrical stimulation of muscles demonstrated that the tail is bent to the dorsal direction by actions of SDM and SDL, curved laterally by those of SDL, CL, CM and SVL, bent to the ventral direction by those of SVL and SVM, and rolled by those of CL and CM on both sides. Contraction of SDL and SVL produced rapid and strong tail movements by actions of their long tendons.

Animals↗
PubMed1994

[Maternal drinking and smoking and the risk of birth defects].

Maternal drinking or smoking and the risk of birth defects was studied in a case-control study, performed on 1,789 babies, born between 1990 and 1992 in the Tokai University hospital, and their mothers. The findings were as follows: The proportion of maternal drinking before or during pregnancy was higher in the mothers of children with birth defects (odds ratio 2.2; 95% confidence intervals 0.5-8.9). However, this difference was not statistically significant. Maternal smoking, defined as 11 or more cigarettes per day before pregnancy, was 13.5% in the mothers of children with birth defects, compared to 6.7% in the mothers of controls (odds ratio 2.2; 95% CI 0.6-7.4). This difference was not statistically significant. A total of 78 classified deformities were reported in the 52 children with birth defects, of which 24.4% were associated with maternal drinking and 16.7% were associated with maternal smoking, respectively. A significant association was found between premature birth and mothers who reported drinking during pregnancy (odds ratio 3.3 95% CI 1.1-10.9). The frequency of spontaneous abortion was higher among mothers who reported both drinking and smoking during pregnancy. In addition the frequency of complications during pregnancy was higher. Analysis of factors related to birth defects showed that the risk for birth defective infants was higher for mothers above 35 years of age than for those under 35 (p < 0.05). This study supports an association between maternal drinking during pregnancy and infant birth defects, but does not implicate maternal smoking because the number of mothers who smoked during pregnancy was too small to be of significance.

Adult↗
PubMed1994

Sorting out of limb bud cells in monolayer culture.

To examine differences in the surface properties of limb bud cells, we mixed cells from the progress zone at different stages or from different positions along proximodistal axis of chick and quail wing limb buds. To identify the origin of cells, a chick-specific antibody was used in a mixed culture of chick and quail cells, or cells from one of the stages were labeled with a fluorescent dye, PKH-26. Within 18 hours in mixed culture, cells segregated from each other and formed patches of various sizes. The process zone cells at early developmental stages mixed homogeneously with the cells from proximal region of old limb buds and the progress zone cells at late stages mixed homogeneously with the cells from distal region of the old limb buds. These results suggest that surface properties of cells in progress zone change during limb bud development and vary along the proximodistal and anteroposterior axes of the limb bud and that these differences in surface property may correspond to the positional values for limb pattern formation.

Animals↗
PubMed1994

Histochemical fiber composition of cat's tail muscles.

A histochemical analysis was performed on the activity of myofibrillar ATPase following preincubation at pH 10.3 with NADH-diaphorase in the cat tail muscles (ECM; extensor caudae medialis, ECL; extensor caudae lateralis, ACE; abductor caudae externus, ACI; abductor caudae internus, FCL; flexor caudae longus, and FCB; flexor caudae brevis). Muscles contained three types of muscle fibers: FG (fast-twitch glycolytic) showed high reaction of myofibrillar ATPase staining and low reaction in NADH-diaphorase staining; FOG (fast-twitch oxidative glycolytic) showed high reaction in myofibrillar ATPase staining and high reaction in NADH-diaphorase staining; and SO (slow-twitch oxidative) showed low reaction in myofibrillar ATPase staining and high reaction in NADH-diaphorase staining. All 6 tail muscles were composed of these three types of fibers, but proportions differed in each tail muscle. Proportions of SO and FG fibers were highest in ECL (SO: 38.6 +/- 2.3, S.D. %) and ACI (FG: 59.2 +/- 5.0%), respectively. The diameters of the fibers were also measured (SO; 50.47 +/- 3.12, FOG; 58.18 +/- 2.78, FG; 70.91 +/- 3.40, S.D. microns).

Adenosine Triphosphatases↗
PubMed1993

Characterization of upstream activation elements essential for the expression of germ cell alkaline phosphatase in human choriocarcinoma cells.

Expression of the germ cell alkaline phosphatase is a highly regulated process tied to malignant transformation of the human placenta. Human choriocarcinoma cells (malignant trophoblasts) express primarily the germ cell alkaline phosphatase gene and only low or nondetectable levels of the placental alkaline phosphatase normally found in the human placenta. Here, we show that nucleotides -156 to -1 region relative to the gene transcription start site (+1) contain cis-acting DNA elements that direct germ cell alkaline phosphatase expression in choriocarcinoma cells. Within the minimal activator region, at least three nuclear protein-binding sites, I (-63/-44), II (-87/-67), and III (-136/-103), were identified by DNase I footprinting analysis. All three sites are GC-rich. Sites I and II contain a sequence known to bind the transcription factor AP-2; the AP-2 site in site II overlaps a consensus motif for the transcription factor Sp1. Gel retardation experiments showed that similar nuclear protein factor(s) in JEG-3 choriocarcinoma cells bind to all three sites, with highest affinity to sites I and II. Site-directed mutagenesis that prevents binding of nuclear proteins to either site I or II, or both sites I and II, resulted in the loss of factor binding and reduced activator activity. The germ cell alkaline phosphatase promoter that contains an intact binding site III but altered sites I and II had little activator activity, suggesting that protein-protein interaction is important for germ cell alkaline phosphatase gene activation.

Alkaline Phosphatase↗
PubMed1993

Electromyographic and kinematic studies of tail movements in dogs during treadmill locomotion.

Electromyographic (EMG) activities of three tail muscles, the extensor caudae lateralis (ECL), abductor caudae externus (ACE), and flexor caudae longus (FCL), were recorded bilaterally in seven adult dogs during walking, trotting, and galloping on a treadmill. Each dog's movements were recorded with a 16 mm high-speed camera system, and angular movements of the tail were analyzed. During walking and trotting, reciprocal EMG bursts were observed between right and left tail muscles and corresponded with lateral movements of the tail. The tonic discharges that were observed in ECL and FCL seemed to maintain the position of the tail. During galloping, synchronized EMG activity of all tail muscles produced reactive torques to counter those generated by cyclic limb movements and kept the tail in a stable position. These results suggest that tail movements are important in maintaining body balance during locomotion in the dog.

Animals↗
PubMed1993

Differential effects of footpad stimulation on the monosynaptic reflex in the spinalized cat.

Experiments were performed in 17 adult cats spinalized at T10-11. The effects of electrical stimulation of the central pad (CP) and toe pads (TP-2, 3, 4, 5) on the monosynaptic reflex (MR) in lumbar spinal segments were studied. The conditioning stimulation had different effects on the MRs of the various motoneurons except the posterior biceps and semitendinosus, depending on the footpad stimulated. Lateral gastrocnemius and soleus, and medial gastrocnemius (MG) MR were inhibited by footpad stimulation. The effect of TP-2 (medial footpad) stimulation on MG-MR was weak. The popliteus (Pop) and tibialis anterior muscles (TA) are inward and lateral rotators of the knee joint, respectively. Pop- and TA-MR were excited by stimulation of lateral and medial TPs, respectively. Plantaris MR was enhanced and inhibited by stimulation of the CP and TPs, respectively. There were remarkable differences in the effects of TP conditioning stimulation on the flexor digitorum longus, extensor digitorum longus, peroneus brevis and tertius, and peroneus longus-MRs, depending on the toe pads stimulated. These results suggest that afferent inputs from footpads modulate the activity of motoneurons, stabilize the foot and help maintain body balance.

Animals↗
PubMed1993

Effects of afferent inputs from mechanical and nociceptive receptors in the footpads on the monosynaptic reflex in the spinalized cat.

We previously reported that the effects of footpad stimulation on the monosynaptic reflexes (MRs) in the cat's lumbar spinal cord depended on stimulated footpads. In this study, the effects of different types of stimulation (tonic pressure, phasic pressure, squeezing and radiant heating at 50 degrees C) on the MRs were studied in 12 adult cats spinalized at T11-12. The effects of tonic pressure were very weak or not detected. The pattern for the effects of phasic pressure was similar to that for squeezing, but the effects of squeezing was stronger than those of phasic pressure. These results indicate that effects of mechanical stimulation were mainly induced from phasic afferent inputs. Radiant heating was effective, and differential effects between mechanical stimulation and radiant heating were observed in some MRs. Our results suggest a difference in neuronal pathways from various types of receptors in the footpads.

Afferent Pathways↗
PubMed1993

Descending projections to coccygeal spinal segments in the cat.

The descending projections to coccygeal spinal segments influencing tail movement were studied by retrograde wheat germ agglutinin-horseradish peroxidase (WGA-HRP) tracing methods in 12 cats. WGA-HRP solution was injected into the 3rd and 4th coccygeal segments and hemisection of the right side of the spinal cord was performed at the 3rd sacral-1st coccygeal segmental level. Labelled propriospinal neurons were distributed in laminae III-VIII and X of the spinal cord between the cervical and lumbosacral spinal segments, predominantly on the left. The greatest density of labelled cells as in the lumbar enlargement. In the brainstem a high density of labelled cells was observed mainly in the lateral vestibular, gigantocellular reticular and magnocellular reticular nuclei on the left side, and the nucleus raphe magnus, pallidus and obscurus. These findings indicate significant descending projections to the coccygeal spinal cord in the cat which could be responsible for tail movements in the cat.

Animals↗
PubMed1993

[Gene expression of MMPs and TIMPs in the process of hepatic fibrosis].

The matrix metalloproteinases (MMPs) gene family includes MMP-1 (interstitial collagenase), MMP-2 (72 kD type IV collagenase/gelatinase), MMP-3 (stromelysin/transin), MMP-7 (putative MMP; pump-1), MMP-8 (granulocyte collagenase) and MMP-9 (92 kD type IV collagenase/gelatinase). This gene family has the common characteristics in the gene structure as follows: All of MMPs have the active site metal ion-binding domain. All six enzymes are activated with the concomitant removal of N-terminal segment of the latent enzyme. The removed segment contains an unpaired cystein residue within the conserved amino acid sequence PRCGVPDV, located immediately adjacent to the proenzyme cleavage site. The authors showed the gene expression of MMP-1 in the process of hepatic fibrosis. The remarkable expression was noted on fibroblasts and macrophages within the newly-formed fibrous bands with lots of infiltrated lymphocytes. Liver cirrhosis did not showed the positive dots of MMP-1 mRNA. On the other hands, the expression of TIMP reported by Takahara et al., revealed the high level of expression in the advanced fibrosis.

Amino Acid Sequence↗
PubMed1993

[The partial resection of lung with MULTIFIRE ENDO GIA 30 under the thoracoscopy].

MULTIFIRE ENDO GIA 30 was a newly auto suture developed by US surgical c.o., A 27-year-old man was admitted for right spontaneous pneumothorax in our hospital. We performed the partial resection of lung with this new auto suture under the thoracoscopy. Condition of patient after operation was very good, and he could discharge in short hospitalization. We concluded that this new auto suture was entirely reversible and safety.

Adult↗
PubMed1992

Structural and functional analysis of human germ cell alkaline phosphatase by site-specific mutagenesis.

Human germ cell alkaline phosphatase (GCAP), which shares 98% amino acid sequence identity with the placental AP (PLAP), is expressed by malignant trophoblasts. Protein sequence analysis suggests that the Ser residue at position 92 is the putative active site of GCAP which contains two recognition sequences (Asn122-Thr-Thr124 and Asn249-Arg-Thr251) for asparagine-linked glycosylation. To examine the roles of the Ser residue and glycan moieties on GCAP activity and processing, we altered the GCAP cDNA by site-directed mutagenesis and expressed the GCAP mutants in COS-1 cells. Substitution of Ser-92 with either a Thr (S92T) or an Ala (S92A) residue yielded a GCAP devoid of catalytic activity, suggesting that the Ser codon 92 is the active site of GCAP. Six GCAP mutants that lack one or both glycosylation sites were constructed by substituting either Asn-122 or Asn-249 with an Asp residue or either Thr-124 or Thr-251 with an Ala residue. The mature GCAP migrated as a 65-kDa product, but GCAP mutants lacking one or both glycosylation sites migrated as 62- or 58-kDa polypeptides, respectively, indicating that both sites were glycosylated. All six glycosylated mutants were active enzymatically and, in addition, were equally sensitive to heat, L-leucine, and EDTA inhibition as the parental enzyme. GCAP as well as its two active-site and six glycosylation mutants could be released from the plasma membrane of transfected COS-1 cells by the proteinase bromelain.(ABSTRACT TRUNCATED AT 250 WORDS)

Alkaline Phosphatase↗
PubMed1992

Antibodies to native type III collagen in the serum of patients with Kawasaki disease.

Pathological studies have revealed that the vasculitis in Kawasaki disease (KD) begins in the intima and the adventitia of blood vessels resulting in panvasculitis. In the present study we investigated the possibility that auto-antibodies to types III and II collagen are involved in the vascular injury. Seven out of 38 patients (18%) with KD had elevated serum levels of IgG antibody to type III collagen. None had increased serum antibodies to type II collagen. Specificity of the antibody to type III collagen in patients with KD was 86%. Three out of seven KD patients (42.9%) with coronary complications had elevated serum levels of the antibody. It is conceivable that the more severe the inflammation of systemic blood vessels, the more frequently antibodies to type III collagen are detected and coronary complications develop. Accordingly, this antibody may be secondarily detected in the serum of KD when systemic blood vessels are severely damaged. Detection of antibodies to type III collagen might be a risk factor predicting coronary complications.

Autoantibodies↗
PubMed1992

Dose-related effects of the hepatocarcinogen, Wy-14,643, on peroxisomes and cell replication.

The dose and time dependency of peroxisome proliferation and hepatocyte replication was evaluated in the liver of rats fed the peroxisome proliferator and hepatocarcinogen, Wy-14,643. Male F344 rats were fed NIH07 diet blended with Wy-14,643 at 0, 5, 10, 50, 100, or 1000 ppm for 1, 3, 6, or 13 weeks. Hepatomegaly was induced by Wy-14,643 at all doses and at all time points. Peroxisome proliferation was present in rats fed 5 ppm Wy-14,643 as early as 1 week, as determined by the peroxisome-specific NAD+ reduction of palmitoyl CoA (PCO) and the peroxisome-associated activity of carnitine acetyltransferase (CAT) (5- and 11-fold over control, respectively). The elevations of PCO and CAT were dose-dependent from 5 to 50 ppm and then plateaued from 50 to 1000 ppm throughout the treatment period. Hepatocellular replication, evaluated by nuclear histoautoradiography ([3H]thymidine labeling, 6-day infusion), was increased in all Wy-14,643 dose groups after 1 week of treatment (5 ppm, 4-fold; 10 ppm, 5-fold; 50 ppm, 13-fold; 100 ppm, 12-fold; and 1000 ppm, 13-fold over controls). However, in 5 and 10 ppm groups this cell replication returned to control levels by 3 weeks. In contrast, 50, 100, and 1000 ppm groups had sustained increases in cell replication up to 13 weeks (13 weeks: 6-, 7-, and 9-fold over controls, respectively). We have demonstrated that Wy-14,643 can induce peroxisome proliferation at 5 ppm, a dose 200 times lower than the dose shown to be highly hepatocarcinogenic in rats (100% incidence by 60 weeks).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗