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Biomedical subjects

K Ogihara

Publications and source records attributed to K Ogihara.

At least 37 records · Page 2Linked to original sources
PubMed1998

"Kissing" bilateral large carotid-ophthalmic aneurysms. A case report.

A case of unruptured bilateral large carotid-ophthalmic aneurysms, which appear to be adjoining and "kissing" each other when visualized by three-dimensional computed tomographic angiography (3-D CTA), is reported. Although bilateral carotid-ophthalmic aneurysms are not rare, bilateral large ones are quite rare, and direct imaging of "kissing aneurysms" of this portion has not been reported. Since 3-D CTA is becoming a useful tool for the diagnosis of cerebral aneurysms, we propose that these and similar bilateral large carotid-ophthalmic aneurysms are good candidates for the term "kissing aneurysms".

Aged↗
PubMed1998

Glomerular vascular changes in KK-Ay mice with early diabetes: scanning electron microscopy of vascular resin casts.

Vascular changes, the angioarchitecture of renal glomerular fine vessels in early diabetic KK-Ay mice of 4 months of age were examined by scanning electron microscopy of corrosion casts. Histologically, enlargement of glomeruli and dilation of glomerular capillaries were found. In resin cast specimens, glomeruli with diabetes were larger than normal, and an increase in diameter of the glomerular vessels was found in diabetic mice. No capillary proliferation, distortion of glomerular vessels and destruction of glomerular capillary loops were found in diabetic mice. The increased vascular diameter may explain the increase in blood flow in the glomeruli, affecting kidney function in early diabetes.

Animals↗
PubMed1998

Treatment of a Brodie bite by lower lateral expansion: a case report and fourth year follow-up.

The patient was a 4 year 4 month old boy at the first visit. The chief complaint was chewing dysfunction. The intra-oral and facial films, study casts, cephalometrics, muscle-balance monitor, temporomandibular joint radiographs were analyzed. The patient presented with a Brodie bite or unilateral posterior cross bite. The upper dental arch was wider than other children of his age. The lower dental arch was significantly smaller than the upper dental arch. The lower dental arch was expanded using a Schwarz appliance. The period of treatment was one year and two months. The period of observation was four years and ten months. First the patient underwent chewing training and secondarily then was treated by lateral expansion. After this treatment the patient achieved good occlusion and muscle function, while the morphology and function of the temporomandibular joints were improved, as well.

Cephalometry↗
PubMed1997

Three-dimensional analysis of vasospastic major cerebral arteries in rats with the corrosion cast technique.

BACKGROUND AND PURPOSE: Although mice, rats, and other small animals are commonly used for molecular biology research, their use in the evaluation of cerebral vasospasm after subarachnoid hemorrhage is somewhat problematic because of the correspondingly small size of their cerebral vessels. We have already reported that the corrosion cast technique was useful for evaluating newly formed cerebral vessels in neural grafts in these small animals. In the present study we applied the corrosion cast technique to the evaluation of hemolysate-induced cerebral vasospasm in rats and performed three-dimensional analysis for comparison. The casting was done 10 minutes after the hemolysate injection, so that only acute "vasospasm" was assessed. METHODS: After withdrawal of 0.1 mL cerebrospinal fluid, 0.2 mL hemolysate (n = 9) or saline (n = 10) was injected into the cisterna magna of male Sprague-Dawley rats weighing between 300 and 350 g. Ten minutes later, perfusion of a semipolymerized casting medium was performed at an injection pressure of 100 to 120 mm Hg. The brains were immersed and corroded in 10% NaOH solution. After these procedures, the basilar artery as well as peripheral vessels was analyzed morphologically with scanning electron microscopy. Conventional histological analysis with the use of paraffin-embedded section with hematoxylin-eosin staining was also performed, and the results were compared with those for the corrosion cast methods. RESULTS: In the saline-injected group, SEM showed that the inner surface of the basilar artery was smooth and the form of the endothelial cell was printed on the surface of the cast. In the hemolysate-injected group, the basilar artery showed an apparent vasospasm over its entire length, and corrugation was observed on the inner surface of the basilar artery in a three-dimensional fashion. Higher magnification revealed that the nuclei of the endothelial cells were distorted. Local narrowing of the basilar artery and vasospasm in the arteries of the anterior circulation and in peripheral arteries were also observed. Measurement of the inner diameter of the basilar artery showed 37.8% contraction in the hemolysate-injected group compared with the saline-injected group by the corrosion cast method. This degree of vasospasm was similar to that observed by the conventional histological method. CONCLUSIONS: In this report we show that detailed three-dimensional observation in the rat can be performed qualitatively and quantitatively with the corrosion cast technique. We conclude that this method derives an accurate measurement of the diameter of rat major cerebral arteries and is more reliable for analyzing vasospasm in rats than angiography and other conventional procedures.

Animals↗
PubMed1996

Role of extracellular matrix in experimental vasospasm. Inhibitory effect of antisense oligonucleotide on collagen induction.

BACKGROUND AND PURPOSE: Although it has been suggested that collagen plays a role in the pathogenesis of cerebral vasospasm after subarachnoid hemorrhage, there has been no constructive research to prove it directly. In this study we stopped the transcription of the procollagen type I gene by introducing antisense oligonucleotides for its mRNA in a rat femoral artery model of vasospasm induced by blood and assayed the changes in the vasoconstrictive activity of the vessel and expression of the procollagen mRNA. METHODS: We applied antisense, sense, or missense oligonucleotides, located at the carboxyl propeptide region for alpha 1(I) procollagen mRNA, onto the femoral artery in a rat femoral artery model of vasospasm. The diameter of the artery was measured by angiography. The transcription level of the procollagen gene in the arterial tissue was assayed by use of reverse transcription-polymerase chain reaction. Morphological change in the artery was observed with aldehyde-fuchsin-Masson-Goldner staining. RESULTS: In the model, when the artery was exposed to antisense oligonucleotides in pluronic gel for 5 days to prevent arterial contraction, the contraction was inhibited at a significant level (76.0% +/- 5.6) when compared with that in control experiments using sense oligonucleotides (64.0% +/- 2.4), missense oligonucleotides (63.5% +/- 3.5), or gel alone (62.1% +/- 5.8). The application of antisense oligonucleotide resulted in a marked decrease in alpha 1(I) procollagen mRNA expression as determined by polymerase chain reaction, indicating that the collagen reduction by antisense oligonucleotides occurred at the transcription level. Histological staining suggested that collagen accumulation at the site in the artery where antisense oligonucleotide had been administered was indeed less than that in the control artery. CONCLUSIONS: The results indicate that the induction of procollagen type 1 could cause pathogenesis of the arterial contraction induced by blood in a rat femoral vasospasm model.

Animals↗
PubMed1996

Inhibition of vascular contraction by intracisternal administration of preproendothelin-1 mRNA antisense oligoDNA in a rat experimental vasospasm model.

To clarify the role of endothelin-1 (ET-1) in the etiology of hemolysate-induced contraction of vessels, the authors introduced antisense oligoDNA for preproendothelin-1 (ppET-1) messenger RNA in a rat model of vasospasm. Phosphorothioate antisense oligoDNAs for ppET-1 were injected into the cisterna magna. Fluorescein isothiocyanate-labeled phosphorothioate antisense oligoDNAs were proven by fluorescence chasing to be incorporated into the vascular wall. Striking inhibitory effects of experimental vasospasm were observed in the basilar artery (BA) in which the oligoDNAs were injected. The vascular contraction was significantly inhibited by oligoDNAs after 20 minutes of hemolysate exposure, which suggested that ET synthesis started approximately 20 minutes after hemolysate stimulation. Expression of ppET-1 in the BA in which the spasm was inhibited was markedly suppressed at the transcription level. The results indicate that ET-1 may play an important role in hemolysate-induced vasoconstriction in rats. In addition, the antisense approach in the cerebrospinal fluid might be a useful tool for preventing cerebral vasospasm.

Animals↗
PubMed1993

Vascular architecture of 3-methyl choranthrene-induced rat fibrosarcoma demonstrated by scanning electron microscopy of resin casts.

A detailed knowledge of the vascular system of tumors is requisite to a clear understanding of tumor physiology and pathology. Accordingly, in this study, examination was made of the vascular architecture of rat fibrosarcomas induced by 3-methyl choranthrene by scanning electron microscopy of resin casts to observe the three-dimensional vascular pattern of the sarcoma. The results were compared with those of corresponding serial sections of India ink-injected tissue. The major arteries in and around tumors appeared devoid of intra-arterial cushions which regulate blood flow. The arterial lining of resin casts was smooth just at the site where it entered the tumor. This may possibly be indication of degeneration and loss of the smooth muscle layer in the vascular wall. Casts of capillaries were very thin from 4 to 6 microns in diameter and very few sprouts could be seen. Capillaries, frequently present in superficial regions of the tumor, formed a rich irregular fine polygonal network. In fibrous tissue in deeper regions of the tumor, this network was coarse. The absence of intra-arterial cushions and degeneration of muscle cells may thus possibly be the reason for the characteristic haemodynamics of tumors.

Animals↗
PubMed1990

[Flavonoid constituents of Melicope triphylla MERR.II].

From the leaves of Melicope triphylla MERR., three new flavonoids (1-3) were isolated, together with nine known flavonoids, 4',5-dihydroxy-3,3',7- trimethoxyflavone (4), 5-hydroxy-3,3',4',7-tetramethoxyflavone (5), 3,3',4',5,7-pentamethoxyflavone (6), 7-hydroxy-3,3',4',5,8-pentamethoxyflavone (7), 3,3',4',5,7,8-hexamethoxyflavone (8), 5-hydroxy-3,7,8-trimethoxy-3',4'-methylenedioxyflavone (9), 7-hydroxy-3,5,8- trimethoxy-3',4'-methylenedioxyflavone (10), 3,5,7,8-tetramethoxy-3',4'-methylenedioxyflavone (11), and 5-hydroxy- 3,6,7,8-tetramethoxy-3',4'-methylenedioxyflavone (12). The structures of 1, 2, and 3 were established as 5-hydroxy-3,7-dimethoxy-3',4'-methylenedioxyflavone, 5-hydroxy-7-isopentenyloxy-3,8-dimethoxy-3',4'-methylenedioxyfl avone, and 4'-hydroxy-7-isopentenyloxy-3,3',5,8-tetramethoxyflavone by their respective chemical and spectral data. The 20 flavonoids isolated from this plant were examined for the piscicidal activities.

Animals↗
PubMed1989

[A case report: occlusal guidance of Angle Class II malocclusion with dysfunction of the masticatory system].

The purpose of this study was to evaluate the condylar changes induced by Bionator therapy. The pre and post treatment Cephalometric, tomographic, and dental cast record were evaluated. An 11-Year, 8 month-old boy with malocclusion class II div. 1 was referred to the Pedodontic clinic of the Nippon Dental University Hospital with a chief complaint of Brxism and Protrusion. The medical history was non-contributory. The period of the observation was 3 years 2 months. Normal permanent occlusion was obtained after treatment. The cephalometric findings showed a favorable relationship between the results of the skeletal and dental changes. Also the results showed an effect on the maxilla and mandible stimulation, class II skeletal correction. Favorable changes in the mandibular condylar position using the Bionator were observed in tomographic records before and after treatment.

Activator Appliances↗
PubMed1984

The organ distribution of tin and the effect of tin on concentrations of several essential elements in rabbit.

The organ distribution and the effects of administration of tin, 5 mumol/kg/day, for 6 days on calcium, copper, iron, magnesium, phosphate, and zinc concentrations in plasma, erythrocytes, liver, kidney, and spleen of adult rabbits were studied. Kidney contained the highest concentration of tin, 15.0 +/- 1.64 micrograms/g wet weight (mean +/- S.D., n = 4). The concentrations of copper, phosphate, and magnesium increased significantly in the kidney, while magnesium concentration decreased in erythrocytes 1 day after the administration of tin for 6 consecutive days. A high correlation coefficient between magnesium and phosphate was observed in all organs tested. The correlation coefficients between P vs. Cu, P vs. Ca, and Mg vs. Ca in the liver were lowered during the period of tin administration, whereas those between P vs. Zn, Mg vs. Zn, and Cu vs. Zn in the kidney disappeared after tin administration was completed.

Animals↗