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Biomedical subjects

K Yuda

Publications and source records attributed to K Yuda.

At least 19 recordsLinked to original sources
PubMed1999

Design of potent phosphorothioate antisense oligonucleotides directed to human interleukin 10 gene product and their evaluation of antisense activity in U937 cells.

PURPOSE: The two objectives of this study were to design potent phosphorothioate antisense oligonucleotides (AS-S-oligos) directed against the human interleukin-10 (IL-10) gene product and to reveal the DNA sequence which best activates antisense effects. METHODS: The design of potent AS-S-oligo was performed by using melting temperature (Tm) value of a DNA/RNA hybrid calculated by the nearest neighbor method and a secondary structure of human IL-10 mRNA suggested by RNA folding algorithms. U937 cells were used to estimate the antisense effect of the AS-S-oligos. RESULTS: Of the eight candidates selected as potent AS-S-oligos on the basis of having higher Tm values and favorable secondary structures of the IL-10 mRNA, AS-S-oligos directed against the translated (AS367-S-oligo) and 3'-untranslated (AS637-S-oligo) region of IL-10 mRNA showed the strongest inhibitory effects on IL-10 production and this inhibition was dose- and time-dependent. Reverse transcription-polymerase chain reaction (RT-PCR) revealed that the antisense effects of AS-S-oligos originated from a specific reduction of target IL-10 mRNA by hybridization with AS367- and AS637-S-oligos. In addition, these AS-S-oligos did not affect human tumor necrosis factor-alpha (TNF-alpha) production in the cells stimulated by lipopolysaccharide (LPS). Strong positive correlations between the inhibitory effect of AS-S-oligos on the IL-10 production and not only Tm values calculated by nearest neighbor method but also Tm values determined by absorbance versus temperature profiles were demonstrated except for AS25-S-oligo and AS1249-S-oligo. CONCLUSIONS: These findings suggest AS367- and AS637-S-oligos powerfully inhibit IL-10 production in U937 cells via an antisense mechanism. In addition, it is suggested efficiency of AS-S-oligo directed against the sequence of the target gene product can be explained by these Tm values and the proposed secondary structures of the target gene product.

Drug Design↗
PubMed1996

Constructing an efficient trans-acting genomic HDV ribozyme.

We have engineered a genomic HDV ribozyme to construct several trans-acting ribozymes for use in trans to cleave target RNAs. Among the 10 different combinations attempted, only HDV88-Trans had cleavage activity on the 13-nucleotide substrate, R13, in vitro. To improve the cleavage efficiency, at least in vitro, of the HDV88-Trans ribozyme (kclv = 0.022 min(-1)), we have constructed several variants that differ in forming stem II (length) in the pseudoknot secondary structure model. When cleavage rate constants were analyzed and compared among variants of HDV88-Trans, HDV88-Trans-4 yielded kclv = 1.7 min(-1). HDV88-Trans-4 thus represents the highest active genomic HDV ribozyme that functions in trans thus far constructed, and has activity under physiological conditions (pH 7.1 at 37 degrees C with 1 mM of MgCl2).

Base Sequence↗
PubMed1995

[Haemophilus aphrophilus isolated from the blood of a patient with infective endocarditis].

On July 1994, a 62-year-old female, having a history of mitral regurgitation, was admitted because of high fever, hematuria and conjunctival petechiae. She was diagnosed as having infective endocarditis with mitral valve vegetation proved by ultrasonic cardiography. The gram negative rods were isolated from blood cultures performed five times, performed prior to the administration of antibiotics. The isolates were identified as strains of H. aphrophilus. After two days of treatment with PCG (12 million units/day), the organism became undetectable from the blood. Since the minimal inhibitory concentrations (MICs) of PCG and ABPC were ranged between 0.06-2.0 micrograms/ml and 0.06-0.5 microgram/ml, respectively, ABPC was selected as a first choice antibiotic instead of PCG. ABPC was given 12 g/day for the first 3 days, then 6 g/day for 28 days, followed by 3 g/day for 7 days. The patient recovered and was discharged after the 55 hospital days. H. aphrophilus grew on BTB lactose agar, chocolate agar and sheep blood agar, but failed to grow on MacConkey agar. H. aphrophilus produced smooth transparent nonhaemolytic micro colonies after 48 hours on sheep blood agar and chocolate agar plates. Atmosphere with 5% CO2 failed to enhance their growth. All the five strains of H. aphrophilus isolated, required neither factors V nor X. Positive synthesis of porphyrin from delta-aminolevlinic acid confirmed their ability to grow without X factor. For the correct identification of H. aphrophilus strains, fermentation test of glucose, lactose, maltose and sucrose in either phenol red broth or CTA medium are necessary.(ABSTRACT TRUNCATED AT 250 WORDS)

Ampicillin↗
PubMed1993

[A case of Duane's syndrome with ocular melanosis].

Duane's syndrome has various ocular and systemic abnormalities. We report a Duane's syndrome patient with ocular melanosis. Duane's syndrome has many complications, but ocular melanosis has never been reported previously. It is possible that there is a similar mechanism between the ocular melanosis and misdirection of the oculomotor nerve to the external rectus in this case, but it is more probable that it is simply coincidental.

Child↗
PubMed1991

[Abnormal vergence eye movement during eyelid closure caused by a pineal tumor].

A case with abnormal eye movement induced by eyelid closure and selective paralysis of downward gaze was reported. CT scan and MRI imaging revealed a pineal tumor with bilateral involvement of the thalamomesenchephalic junctions without obvious damage to the posterior commissure. Histopathologically, the tumor was a germinoma. The pupillary light reflex was absent and near reflex was reduced. Lightning eye movement, skew deviation and convergence-retraction nystagmus were observed. The horizontal eye movement was normal in both eyes. The eye did not move downward below the level of direct forward gaze spontaneously or on attempted downward gaze. Downward vestibulo-ocular reflex was absent. Bilateral abnormal vergence eye movement with alternating convergence and divergence was observed during eyelid closure. The cycle of the abnormal eye movement was about 3Hz and there was no fast phase. The abnormal eye movement was not observed in the darkened room with both eyes open. After subtotal removal and radiation therapy of the pineal tumor, the abnormal eye movement disappeared.

Adult↗
PubMed1990

[Alteration of prostaglandin I2 on ripening in rabbit uterine cervix].

We have attempted to clarify the relationship between PG synthesis and ripening in rabbit uterine cervix. In this paper, I examined whether PGI2 release from endogenous arachidonic acid is changed in ripening in the uterine cervix. The release of 6-keto PGF1 alpha significantly increased after the 20th day of gestation and at term reached its maximum, which was about six times that of non-pregnant rabbits. I then measured the activity of phospholipase A2 in the tissue and found that it was significantly increased during gestation. Furthermore, to determine which cells synthesize PGI2, several kinds of cells from the uterine cervix of non-pregnant and pregnant rabbits were isolated and cultured. Among these cells, smooth muscle cells were shown to have the PGI2 synthesizing activity. The rate of conversion of arachidonic acid to PGI2 in the cell was about 30%, and that to PGE2 was negligible. To examine the change in PGI2 synthesis with gestational age, cells from both non-pregnant and from the 25th day of gestation were cultured and the release of PGI2 from these cells was determined by radioimmunoassay of 6-keto PGF1 alpha. The release of 6-keto PGF1 alpha in gestation was about three times as high as in the cells from non-pregnant rabbits.

6-Ketoprostaglandin F1 alpha↗
PubMed1990

[Non-neuroectodermal epithelial cyst in the middle cranial fossa associated with unilateral exophthalmos].

A rare case of unilateral exophthalmos caused by an epithelial cyst in the middle cranial fossa was reported. A 42-year-old man had a proptosis of sudden onset in the left eye. Ophthalmological examinations revealed a proptosis of 3mm, contraction of the lower visual field and a bow tie atrophy of the optic disc in the left. Plain skull X-P, CT scan and MRI disclosed a cystic lesion in the left middle fossa, resulting in the enlargement of the superior orbital fissure of the same side. Metrizamide CT cisternography showed the cyst had no communication with the subarachnoid spaces. The cyst, removed surgically, was located in the epidural region of the middle fossa and was about 4cm in diameter, containing yellowish turbid fluid and fat-like floating substance. Histologically, the cyst was composed of collagenous connective tissue, lined with pseudostratified columnar to cuboidal epithelia. Small cells with a high nuclear to cytoplasmic ratio, considered as basal cells or reserve cells, were often seen in the basal layer. Ciliated and secretory cells were rarely observed in the superficial layer. Neither stratified squamous epithelium nor adamantinomatous structure was seen. Immunohistochemical studies revealed that the lining epithelium was strongly positive for keratin (wide spectrum), but negative for vimentin, S-100, neuron specific enolase or glial fibrillary acidic protein. These staining characters were different from those of neuroectodermal cells including ependymal cells and choroidal cells which are usually vimentin- and S-100-positive. Morphologically, the lining epithelium resembled respiratory or alimentary tract epithelium, suggesting that the cyst might be derived from non-neuroectodermal ectoderm or endoderm.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Substance P-like immunoreactivity in the central retinal artery of the rabbit.

Substance P-like immunoreactive nerve fibers were identified in the central retinal artery of the rabbit using the peroxidase-antiperoxidase method. The fibers were seen to encircle the central retinal artery throughout its course in the main trunk of the optic nerve. No labeled fibers were seen in the central retinal vein or in the retinal blood vessels. It appears, therefore, that the central retinal artery and the retinal blood vessels are innervated by different nerve systems: the central retinal artery by one of the peripheral nerves, and the retinal vessels by the central nervous system.

Animals↗
PubMed1988

[Traumatic enucleation of the eye ball--report of a case and considerations concerning the pathogenic mechanism of intracranial complications].

A 48-year-old man had his left eye ball enucleated by fingers of an assailant. The optic nerve, measuring 4 cm in length, was attached to the enucleated eye ball, but there was neither a wound in his eyelids nor cerebrospinal fluid leakage from inside the orbit. He was confused, but responsive and was able to recognize other persons with his right eye. His right-eye vision deteriorated within 24 hours and was almost totally lost for about one month. Three months after the trauma his vision recovered to 0.1, but his visual field showed severe concentric narrowing. An emergency CT on admission showed a small subarachnoid hemorrhage in the suprasellar cistern, and follow-up CT scanning on day 7 demonstrated a small infarction in the left globus pallidus and putamen. Cerebral angiography performed on day 17 showed residual vasospasm of the horizontal portion of left anterior cerebral artery. Left ophthalmic artery was patent and there was no aneurysm formation either on the intracranial or on the intraorbital arteries. Literature review yielded only three cases of eye ball enucleation by an assailant. Intracranial complications reported in the literature, including those associated with eye ball enucleation caused by other mechanisms, are; contralateral visual field defect: seven cases, hypothalamic involvement: two cases, subarachnoid hemorrhage: two cases, cerebrospinal fluid leakage: one case, and meningitis: one case. The optic nerve, from just behind the eye ball to the chiasm, is reported to be 40-50 mm long, and eye ball enucleation with the optic nerve measuring 4 cm or more is quite likely to cause intracranial complications such as are cited above.

Brain Diseases↗
PubMed1986

[Management of full term breech presentation--criteria for safe vaginal delivery (without extraction of the breech head)].

It is very important to appraise cephalo-pelvic disproportion (CPD), and to predict the necessity of extraction of the after-coming head on full-term breech presentation. Subjects were 47 cases of full-term breech presentation which delivered at our hospital during the 5-year period from 1979 to 1983. They were divided into the following groups: group A Assisted breech delivery. group B Extraction of after-coming head. group C Abdominal delivery for secondary inertia. In each case we subtracted the fetal occipitofrontal diameter from the individual pelvic diameter and compared the results for groups A and B. There were significant differences between groups A and B in the mean values (cm) for the following: True antero-posterior diameter of the wide; 1.341 +/- 1.009 and 0.380 +/- 0.379 (p less than 0.001). Antero-posterior diameter of the Fukushima's wide; 2.005 +/- 0.906 and 0.860 +/- 0.502 (p less than 0.01). Posterior-sagittal diameter of the wide; -5.300 +/- 1.026 and -6.020 +/- 0.340 (p less than 0.05). Antero-posterior diameter of the midpelvis; 1.414 +/- 1.035 and -0.110 +/- 0.718 Posterior-sagittal diameter of the midpelvis (Caldwell-Moloy); -5.759 +/- 1.041 and -6.560 +/- 0.573 (p less than 0.05). Posteriol-sagittal diameter of the midpelvis (Thoms): -6.173 +/- 1.083 and -7.430 +/- 0.750 (p less than 0.01). Furthermore, there were also significant differences between groups A and C: The margins of safety values for each pelvic diameter (cm) were as follows: Antero-posterior diameter of the midpelvis; (13.1): Posterior-sagittal diameter of the midpelvis (Thoms); (5.5): Inter-spinous diameter; (11.0): Inter-tuberous diameter; (11.3).(ABSTRACT TRUNCATED AT 250 WORDS)

Birth Weight↗
PubMed1982

[Astroblastoma in newborn baby (author's transl)].

A case of astroblastoma in a male newborn baby was reported. He has been suffered from convulsive seizures from six hours later after the birth, not controlled by the anticonvulsants, and lumbar tap revealed bloody cerebrospinal fluid. He had no response against the noxious stimuli and left clonic hemiconvulsion, and showed anisocoria, left pupil was dilated. Right BAG showed a large space occupying lesion in the right frontal lobe. Operation was performed eighteen hours after the birth. Right frontotemporal craniotomy revealed reddish-grey, soft tumor in the right frontal lobe infiltrating into the parietal and temporal lobe of the same side and frontal lobe of the left side. Right frontal lobectomy was performed. He had cardiac arrhythmia after the operation and died next day. Autopsy was not permitted. Histologically tumor tissue showed abundant vessels and perivascular pseudorosettes, and electron micrograph revealed glial filaments in the tumor cells. Histological diagnosis was astroblastoma.

Astrocytoma↗
PubMed1980

Thermosensitive determination of CSF shunt patency with a pair of small disc thermistors.

A simple method is presented for detecting the patency of ventriculoperitoneal shunts with a pair of small disc thermistors. In an experimental model, the equipment detected definite temperature changes along the shunt tube. The extent of the temperature difference was proportional to the flow velocities, ranging from 5 to 60 ml/hr (120 to 1440 ml/24 hrs). A clinical study consisted of 26 trials in 23 hydrocephalic children and 10 trials in nine adult patients with normal-pressure hydrocephalus. Three of the 26 trials in the children were unsuccessful because of patient irritability and lack of cooperation. All trials for adult patients were successful. In all 25 patients, whose clinical pictures suggested functioning shunt, accurate confirmation of shunt patency was obtained. In six patients whose clinical pictures suggested questionable shunt function, this method revealed that all shunts were patent, and computerized tomography and follow-up clinical data supported this finding. In two patients whose clinical pictures suggested shunt malfunction, there was no indicator deflection, and shunt obstruction was proved at operation. This method is effective in checking shunt function, is simple, and may be repeated at frequent intervals.

Cerebrospinal Fluid Shunts↗
PubMed1978

Cerebral neuroblastoma.

A cerebral neuroblastoma removed surgically from a female child is presented. Electron microscopy showed numerous neuronal processes with growth cones which are a feature of the developing neurone. In addition there were some rosettes with distinct lumina. The luminal surfaces were covered with a smooth plasma membrane lacking any surface differentiation and the lateral surface of these cells had many cell junctions (terminal bars), reminiscent of a primitive neural tube. These features in a nerve cell tumor help to substantiate it as a neuroblastoma arising from immature rather than differentiated cells. The nature of this rare tumor is discussed.

Brain Neoplasms↗