PubMed Health⌕ Search

Biomedical subjects

Y Fujimura

Publications and source records attributed to Y Fujimura.

At least 235 records · Page 13Linked to original sources

[Ehlers-Danlos syndrome with impending ruptured thoracic descending aortic aneurysm in a young adult--a case report].

We here report on a rare case of Ehlers-Danlos syndrome type IV with impending ruptured thoracic aortic aneurysm in a young adult. A 38-year-old man complained of severe back pain and transient paralysis in both legs. He was diagnosed as having an impending ruptured thoracic descending aortic aneurysm. Emergency operation which was aneurysmectomy and reconstruction of the descending aorta was performed. The fact that the aneurysm (11 cm) in a patient was so large for his age and the abnormal subcutaneous fatty tissue suggested the existence of systemic metabolic disease. An analysis of collagen extracted from the patient revealed the absence of type III collagen. Furthermore, an electron microscopic analysis finding that the collagen fibrils was of non-uniform size lead to the diagnosis of Ehlers-Danlos syndrome, Type IV (arterial type). Postoperatively the patient suffered paralysis in both legs due to ischemia of the spinal cord. However, his general condition was stable. He was transferred to another hospital for rehabilitation of both legs 60 days after the operation. Although the physical signs usually associated with Ehlers-Danlos syndrome were absent in this case, diagnosis followed electrophoresis of collagen extracted from the patient. As a result of the above observation, we recommended analysis of collagen in cases where the size of the aneurysm or the age of the patient appear unusual even though physical signs of Ehlers-Danlos syndrome are absent.

Adult↗

Predictability of operative results of cervical compression myelopathy based on preoperative computed tomographic myelography.

The transverse area and flattening ratio of the spinal cord were determined with preoperative computed tomographic myelography in 103 patients with cervical compression myelopathy: cervical spondylotic myelopathy (n = 44); ossification of the posterior longitudinal ligament (n = 39); and cervical disc herniation (n = 20). With these values and other clinical items (eg, age, duration of symptoms, preoperative severity), a linear model to predict postoperative recovery was attempted by multiple regression analysis. In cervical spondylotic myelopathy and ossification of the posterior longitudinal ligament, the transverse area of the spinal cord and the duration of symptoms were accepted as effective explanatory variables to predict recovery. In cervical disc herniation, regardless of the transverse area or duration, the recovery was good, and pathologic state was considered essentially different.

Cervical Vertebrae↗

Human plasma alpha 2-macroglobulin and von Willebrand factor possess covalently linked ABO(H) blood group antigens in subjects with corresponding ABO phenotype.

We recently identified ABO(H) blood group structures in Asn-linked sugar chains of human von Willebrand factor (vWF) purified from factor VIII concentrates (J Biol Chem 267:8723, 1992). We surveyed plasma glycoproteins carrying ABO(H) blood group antigens by Western blotting analysis and sandwich enzyme-linked immunosorbent assay using blood group-specific monoclonal antibodies (MoAbs) and a lectin. Two major plasma proteins showing apparent molecular weight of about 180 Kd and 270 Kd by sodium dodecyl sulfate polyacrylamide gel electrophoresis reacted with blood group-specific MoAbs and Ulex europaeus lectin I in accordance with donor blood group. Direct sequence analysis of the protein bands showed their identity with the N-terminal sequences of alpha 2-macroglobulin (alpha 2M) and vWF, respectively. The two bands also reacted with anti-alpha 2M and anti-vWF antibodies. The alpha 2M and vWF prepared from plasma by immunoprecipitation showed the appropriate blood group antigenicity. After incubation with endoglycosidase F, both alpha 2M and vWF lost almost all reactivity with anti-blood group reagents. About 90% of plasma vWF, but only approximately 10% of alpha 2M, was immunoprecipitated with anti-blood group antibody. These results indicate that at least two plasma glycoproteins, vWF and alpha 2M, possess Asn-linked ABO(H) blood group antigens in normal individuals with corresponding ABO phenotype. Therefore, ABO(H) blood group antigens in plasma glycoproteins should be considered during preparation of plasma materials for therapeutic use.

ABO Blood-Group System↗

Sequence specific binding of Ets-1 to the mouse cytokeratin EndoA gene enhancer.

Expression of the mouse cytokeratin EndoA gene is regulated by an enhancer that is located 1 kilobases (kb) 3' downstream from the gene. The EndoA enhancer consists of six direct repeats with homology to the PEA3 motif in the polyoma virus enhancer core. The PEA3 motif binds to the proto-oncogene Ets product. In this report we show that GST-c-Ets-1 fusion protein binds specifically to the EndoA enhancer unit sequence by gel shift analysis. Footprinting showed that the Ets-1 binding site consisted of 20 bases in each repeat. Ets-1 also moderately activated the EndoA enhancer. These results demonstrate that Ets-1 binds in a sequence specific fashion to the mouse EndoA enhancer and suggest that c-Ets-1 or other related Ets family genes function in regulating EndoA gene expression.

Animals↗

Alboaggregin-B and botrocetin, two snake venom proteins with highly homologous amino acid sequences but totally distinct functions on von Willebrand factor binding to platelets.

Alboaggregin-B (AL-B) (Peng et al., Biochemistry (1991) 30, 11529-11536) was highly purified from the snake venom of Trimeresurus albolabris and characterized structurally and functionally, comparing with botrocetin, another snake venom protein recently characterized (Usami et al., Proc. Natl. Acad. Sci. USA (1993) 90, 928-932). Both the venom proteins are a heterodimer and show a high degree of sequence homology to each other and also to C-type lectins. Botrocetin specifically binds to von Willebrand factor (vWF), whereas AL-B binds to platelet glycoprotein (GP) Ib without affecting the binding of botrocetin to vWF. The binding of AL-B to GPIb does not potentiate the platelet aggregation even by exogenous fibrinogen, suggesting that AL-B binding to GPIb does not activate GPIIb/IIIa complex.

Amino Acid Sequence↗

Primary structure of two-chain botrocetin, a von Willebrand factor modulator purified from the venom of Bothrops jararaca.

The complete amino acid sequence and location of the disulfide bonds of two-chain botrocetin, which promotes platelet agglutination in the presence of von Willebrand factor, from venom of the snake Bothrops jararaca are presented. Sequences of the alpha and beta subunits were determined by analysis of peptides generated by digestion of the S-pyridylethylated protein with Achromobacter protease I or alpha-chymotrypsin and by chemical cleavage with cyanogen bromide or 2-(2'-nitrophenylsulfenyl)-3-methyl-3-bromoindolenine. Two-chain botrocetin is a heterodimer composed of the alpha subunit (consisting of 133 amino acid residues) and the beta subunit (consisting of 125 amino acid residues) held together by a disulfide bond. Seven disulfide bonds link half-cystine residues 2 to 13, 30 to 128, and 103 to 120 of the alpha subunit; 2 to 13, 30 to 121, and 98 to 113 of the beta subunit; and 80 of the alpha subunit to 75 of the beta subunit. In terms of amino acid sequence and disulfide bond location, two-chain botrocetin is homologous to echinoidin (a sea urchin lectin) and other C-type (Ca(2+)-dependent) lectins.

Amino Acid Sequence↗

Assessment of the distribution of nerve conduction velocities in alcoholics.

To assess the effects of chronic alcohol ingestion on the faster and slower nerve fibers (alpha fiber group) in the peripheral nervous system, the distribution of nerve conduction velocities (DCV) and conventional maximal motor and sensory nerve conduction velocities (MCV and SCV) in the median nerve were measured in 23 male patients with severe alcoholic dependency (DSM-III-R), aged 30-64 (mean, 50) years, and in 23 age-matched healthy men. The DCV was expressed by the conduction velocities below which 10, 20,..., 80, and 90% of active fibers lie (V10, V20,..., V80, and V90 velocities). The V40 to V90 velocities of the DCV were significantly slower in the alcoholics than in the control subjects; the SCV and MCV in the alcoholics were also significantly slowed. These findings suggest that the faster large myelinated nerve fibers are more sensitive to chronic alcohol ingestion than the slower large myelinated nerve fibers.

Adult↗

Assessment of central, peripheral, and autonomic nervous system functions in lead workers: neuroelectrophysiological studies.

To assess the effects of lead on central, peripheral, and autonomic nervous systems, the visual-, short-latency somatosensory-, and brainstem auditory-evoked potentials (VEP, SSEP, and BAEP), event-related potential (P300), distribution of nerve conduction velocities (DCV), and electrocardiographic R-R interval variability (CVRR), together with conventional median and radial nerve conduction velocities (NCV), were measured in the lead workers. The lead workers consisted of 22 gun metal foundry workers occupationally exposed to lead, zinc, and copper. In the lead workers with blood lead concentrations below 65 micrograms/dl, the latencies of the VEP (from the retina to the visual cortex), SSEP (from the brachial plexus to the brainstem), and P300 (which reflects cognitive function) were significantly prolonged when compared with the sex- and age-matched controls. All these latencies and the BAEP latencies (from the cochlear nerve to the brainstem) were significantly correlated with the indicators of lead absorption among these workers. The CVRR (especially, a component of parasympathetic activity) was significantly depressed in the lead workers. The slower (V10) velocity of the DCV, the motor, and sensory NCVs were also significantly slowed. These findings suggest that lead affects not only peripheral nerve but also the central and autonomic nervous functions at a subclinical level; zinc may antagonize the neurotoxic effects of lead.

Adult↗

Are faster or slower large myelinated nerve fibers more sensitive to chronic lead exposure? A study of the distribution of conduction velocities.

To determine which of the faster and slower large myelinated nerve fibers (alpha fiber group) are more sensitive to chronic lead exposure, the distribution of nerve conduction velocities (DCV) as well as conventional sensory nerve conduction velocity (SCV) were measured once a month for 20 and 11 months in two male lead workers with blood lead concentrations of 70 to 121 and of 63 to 85 micrograms/dl, respectively. Differences in the frequency beyond the "normal" ranges between conduction velocities of faster nerve fibers (V80, V90, or SCV) and those of slower fibers (V10 or V20) were analyzed by the McNemar test. In the two lead workers, the values below the lower normal limits for the V80 and V90 velocities were more frequent than those for the V10 and V20 velocities; similarly, lower values for the SCV were more frequent than those for the V10 and V20 velocities (P < 0.05). It was suggested that faster nerve fibers are more sensitive to chronic lead exposure than slower nerve fibers. These findings agree with our published data on the effects of local vibration, thallium, n-hexane, styrene, mixed organic solvents, alcohol dependency, and diabetes mellitus.

Humans↗

Mechanical properties of laser welds of titanium in dentistry by pulsed Nd:YAG laser apparatus.

The use of titanium in dentistry is increasing, and an adequate method of joining titanium units of restorations is needed. This study examined the welding of titanium with a normal pulse Nd:YAG laser. Laser welding of titanium was effective when performed in an argon atmosphere. ANOVA for the three-point bending test showed a correlation between the bending strength of a weld, the atmosphere under which the irradiation is performed, and the intensity of the irradiation.

Analysis of Variance↗

A carcinoid tumor of the rectum removed by strip biopsy.

In a 29-year-old male complaining of constipation, total colonoscopy revealed a 5 mm yellowish submucosal tumor at a distance of 6 cm from the anal ring. The histologic diagnosis of specimens obtained by biopsy was rectal carcinoid tumor and transanal ultrasonography revealed the tumor localization within the submucosal layer in the rectum. A strip biopsy was performed. Histopathological examination confirmed the diagnosis and ascertained complete excision. Rectal carcinoid tumors should be removed completely and strip biopsy may be a suitable procedure for removal of rectal submucosal tumors less than 10 mm in diameter.

Adult↗

Molecular genetic analysis of the ABO blood group system: 2. cis-AB alleles.

We have determined the nucleotide sequence of the coding region in the last two coding exons of ABO genes from two cis-AB individuals (genotype cis-AB/O) with no consanguinity. In this region, cis-AB alleles from these 2 individuals were identical to one another while different from the A1 allele by two nucleotide substitutions. Both of these nucleotide substitutions result in amino acid substitutions. The first substitution is identical to the one previously found in the A2 allele. The other substitution is found at the fourth position of the four amino acid substitutions which discriminate A1 and B transferases.

ABO Blood-Group System↗

Low shear stress can initiate von Willebrand factor-dependent platelet aggregation in patients with type IIB and platelet-type von Willebrand disease.

Platelets exposed to shear stress aggregate in the absence of exogenously added agonists, utilizing distinct platelet membrane receptors and ligands depending upon the level of shear stress applied. Using a modified cone and plate type viscometer, we previously demonstrated that, under low shear stress (18 dyn/cm2), aggregation is mediated by platelet membrane glycoprotein (GP) IIb-IIIa and fibrinogen, whereas aggregation induced by high shear stress (108 dyn/cm2) requires the binding of von Willebrand factor (vWF) to both GPIb-IX and GPIIb-IIIa (Ikeda, Y., M. Handa, K. Kawano, T. Kamata, M. Murata, Y. Araki, H. Anbo, Y. Kawai, K. Watanabe, I. Itagaki, et al. 1991. J. Clin. Invest. 87:1234-1240). Here we report that vWF-dependent aggregation occurs under low shear stress in citrated platelet-rich plasma (PRP) from two types of congenital bleeding disorders, platelet-type von Willebrand disease (vWD) and type IIB vWD, in both of which ristocetin-induced aggregation is known to be heightened. Aggregation induced by low shear stress was enhanced in both types of disorders compared to normal controls, and the enhancement was completely abolished by anti-vWF monoclonal antibody NMC-4, which blocks the GPIb-binding site on vWF. Under high shear stress, the extent of maximal aggregation was not different between controls and the patient groups although maximal aggregation was reached much more quickly in the latter. When citrated PRP was exposed to a gradient of shear stress (6 to 108 dyn/cm2 over a 5-min period), vWF-dependent aggregation, as judged from the inhibitory effect of NMC-4, first occurred at 14 dyn/cm2 in platelet-type vWD and at 10-12 dyn/cm2 in type IIB vWD, as compared with more than 81 +/- 20.1 dyn/cm2 in control platelets. These results suggest that an abnormality in either vWF or GPIb-IX triggers the aggregation-inducing interaction of the two molecules under low shear stress, which might explain the intravascular platelet clumping, that presumably underlies the thrombocytopenia observed in these bleeding disorders.

Humans↗

[Isolation of HIV-1 and its correlation with various HIV-markers in Japan].

In Japan, the isolation rate of HIV-1 has increased in recent years, and has become as high as 36.7% in 1991. In order to evaluate the onset of AIDS, we have collected various HIV markers, which were obtained from surveillance committee of Natural History. These data include a total of 1991 specimens (actual number 556 individuals) from Japanese hemophiliacs and non-hemophiliacs since 1985. The data analysed CDC stage, leucocyte counts, lymphocyte counts, CD4+ cell counts, CD8+ cell counts, CD4/CD8 ratio and immunoglobulins (IgA, IgG, IgM). The results indicate that in HIV-isolation positive patients, leucocyte counts, lymphocyte counts, CD4+ cell counts, CD8+ cell counts and CD4/CD8 ratio were significantly lower than those of HIV-isolation negative patients in both hemophiliacs and non-hemophiliacs. IgA value of the positive patients was significantly higher than that of the negative patients, while the IgM value showed converse results to the IgA, in hemophiliacs only. In general, the difference of each HIV marker in non-hemophiliacs was more conspicuous than those in hemophiliacs.

Acquired Immunodeficiency Syndrome↗

[Successful surgical treatment of patent ductus arteriosus in adults: report of three cases].

Three elderly patients underwent surgery for patent ductus arteriosus successfully. In two patients without calcification of ductus arteriosus, its division through a left thoracotomy was performed. In another patient with massively calcified ductus arteriosus associated with pulmonary hypertension, transaortic patch-closure of the aortic end of the ductus arteriosus was performed under partial cardiopulmonary bypass. All three patients and uneventful postoperative course.

Calcinosis↗

[Pulmonary venous obstruction after repair of total anomalous pulmonary venous drainage: report of a case with reoperation].

A 8-month-old infant with Darling' type Ib of total anomalous pulmonary venous drainage underwent surgical correction. Common pulmonary vein drained into superior vena cava. Pulmonary venous channel was constructed between orifice of common pulmonary vein and atrial septal defect (ASD) with pericardial baffle drainage. Pulmonary venous obstruction occurred at the site of ASD and pericardial baffle was atrophic. ASD was enlarged and new pulmonary venous channel was reconstructed with EPTFE graft. Post-reoperative clinical course was uneventful.

Female↗

[The amnioinfusion therapy of saline solution for premature rupture of the membranes before 27 weeks' gestational age].

Saline solution amnioinfusion was performed for 12 cases of preterm PROM before 27 weeks gestational age complicated by oligohydramnios in order to suppress chorioamnionitis, prevent fetal pulmonary hypoplasia and delay delivery. The results were as follows. 1. The mean gestational ages at diagnosis of premature rupture of membranes and initiating saline solution amnioinfusion were 23.6 +/- 2.9 weeks and 24.9 +/- 1.5 weeks, respectively. The mean duration of saline solution amnioinfusion was 14.7 +/- 11.9 days. The mean gestational age at delivery was 27.2 +/- 1.7 weeks. The mean birth weight was 1,056 +/- 220g. 2. Saline solution amnioinfusion was effective in relieving oligohydramnios in all cases. No pulmonary hypoplasia was observed in the infants. 3. Clinically saline solution amnioinfusion was effective in suppressing chorioamnionitis in 9 cases out of 12. Histologically the picture of chorioamnionitis was revealed in 10 cases out of 12. no serious infection was observed in the infants. 4. Nine infants out of 12 survived. There were 2 IUFD and one neonatal death. The perinatal survival rate was 75%. 5. It is concluded from the above results that saline solution amnioinfusion is an effective treatment for preterm PROM before 27 weeks' gestational age.

Amnion↗