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Biomedical subjects

Y Shirahata

Publications and source records attributed to Y Shirahata.

18 recordsLinked to original sources
PubMed2001

New technique for gene transfection using laser irradiation.

BACKGROUND: We have developed a gene transfection system using laser beams. The principle of this procedure is that a small hole is made in a cell membrane by pulse laser irradiation, and a gene contained in a medium is transferred into the cytoplasm through the hole. This hole disappears immediately with the application of laser irradiation of the appropriate power. METHODS: A pulse-wave Nd:YAG laser with a wavelength of 355 nm was used to make a hole in a cell membrane. To trap a cell, a continuous-wave Nd:YAG laser with a wavelength of 1015 nm was used. Plasmids that encode the enhanced green fluorescent protein (EGFP) gene were contained in a medium and transferred to HuH-7 and NIH/3T3 cells with pulse laser irradiation. We evaluated transfection efficiency on the basis of the number of cells that expressed EGFP. Stimulatory protein 2 cells in suspension were fixed using a trapping laser and the neomycin-resistance gene was transfected by pulse laser irradiation. We examined cell proliferation in the selection medium. RESULTS: Cells that expressed EGFP were recognized in the group that was irradiated by pulse laser. No cells expressed EGFP without irradiation. Transfection efficiency was approximately 10% at a plasmid concentration of 10.0 microg/mL. At concentrations greater than 20 microg/mL, the transfection rate reached a plateau. We also successfully transfected neomycin-resistance genes to cells floating in suspension after fixation that was achieved with trapping laser irradiation. CONCLUSIONS: This method enables us to transfect targeted cells, ie, cells in suspension as well as attached cells, with a simple technique that does not involve harmful vectors. The present method is very useful for gene transfection in cellular biotechnology.

3T3 Cells↗
PubMed1996

["Vertigo" the fact analysis of clinical practice by ENT physicians of Chiba Prefecture by "send-out" questionnaires].

Despite the fact that vertigo has been one of the most frequent complaints encountered in daily practice in an ENT outpatient clinic, it is believed to be the most unwelcome subject for ENT physicians. The reasons are diverse; e.g., the understanding of vertigo is still a difficult task for most physicians and requires time-consuming multiple studies. However, answers to those questions, although speculated a posteriori, are yet to be substantiated. Therefore, we have analyzed the data obtained from multiple questionnaires that were addressed to ENT physicians practicing in Chiba Prefecture in November of 1993. However, those who work in publicly run hospitals were excluded from the study. The study included otorhinolaryngologists who were members of the Society of Otorhinolaryngology of Japan. We received filled questionnaire forms from 76 of 155 members (49%). The age ranged from 33 to 82 years (mean 55.8 years, 68 men and 8 women). From these questionnaires, it became apparent that physicians are not necessarily reluctant to see patients with vertigo. Instead, most ENT physicians appeared to be actively paying attention to this symptom and to be making efforts to approach its diagnosis and treatment. Although we are not certain if the data obtained here represent the majority of ENT physicians, the positive attitudes toward the patients with vertigo/dizziness would certainly encourage those of us who are interested in this particular symptom category.

Adult↗
PubMed1995

Cystic adventitial disease of the popliteal artery--a case of young boy.

Cystic adventitial disease (CAD) of the popliteal artery (PA) is rare but one of the well-recognized causes of intermittent claudication. Now more than 200 case reports are available in the world, but there are only 6 cases younger than 15 years old. In this paper, we report a case of 14-year-old boy with CAD of the PA found by intermittent claudication. On examination, the pulses were not palpable below the right popliteal artery, and the angiography demonstrated about 1.5 cm-long obstruction of the right PA. We operated a resection of a cyst with artery, and replaced the autovein graft (V. saphena magna). Cyst contained mucoid degeneration-like ganglion. Two weeks after operation, the angiography showed no stenotic lesion, and follow-up at 4 years showed no symptoms.

Adolescent↗
PubMed1992

Pharmacotherapeutic effects of kuei-chih-fu-ling-wan (keishi-bukuryo-gan) on human uterine myomas.

Kuei-chih-fu-ling-wan (Keishi-bukuryo-gan; KBG), a traditional Chinese herbal remedy contains five components: bark of Cinnamomum cassia Bl. (Lauraceae), root of Paeonia lactiflora Pall. (Paeoniaceae), seed of Prunus persica Batsch. or P. persiba Batsch.var.davidiana Maxim. (Rosaceae), carpophores of Poria cocos Wolf. (Polyporaceae), and root bark of Paeonia suffruticosa Andr. (Paeoniaceae). This prescription has been frequently used in the treatment of gynecological disorders such as hypermenorrhea, dysmenorrhea and sterility. We previously reported that KBG might act as a LH-RH antagonist and a weak anti-estrogen on the uterine DNA synthesis in immature rats. In the present study, we investigated the effects of KBG on 110 premenopausal patients with uterine myomas. Clinical symptoms of hypermenorrhea and dysmenorrhea were improved in more than 90% of the cases with shrinking of uterine myomas in roughly 60% of the cases.

Adult↗
PubMed1990

[Correlation between upper airway tract and lower airway tract in the break down of sinobronchiectasis].

A retrospective study of 44 patients who were involved in combination with chronic sinusitis and bronchiectasis provided better understanding of the etiology in the relationship between upper air ways tract and lower air way tract. The incidence of bronchictasis was found in 5%, 3 out of 60 cases with chronic sinusitis and that of chronic sinusitis in 45%, 44 out of 98 cases with idiopathic bronchiectasis. Both side involvements of the paranasal sinus and the lung were statistically high in sinobronchiectasis compared to chronic sinusitis or bronchiectasis involved alone. The past history of the patients with sinobronchiectasis showed high occurrence of bronchial asthma or allergic rhinitis, habitual angina of the throat, acute otitis media and pneumonia. A chest X. Ray evaluation of 70 patients with chronic sinusitis alone revealed relatively high incidence of abnormal fibro-nodular shadow in the lung compared to 70 patients without chronic sinusitis. It was thought that weakness of air-way tract to infection in the patients with sinobronchiectasis might play some role on break down of sino-bronchial syndrome, a combination disease of chronic sinusitis and chronic bronchitis.

Adolescent↗
PubMed1985

The atelectatic ear and its classification.

Atelectasis of the middle ear cavity occurs in advanced chronic otitis media with effusion. Atelectasis with effusion may progress to atelectasis without effusion, and further possible complications include adhesive otitis, ossicular disruption, cholesteatoma, and sensorineural hearing loss. A classification is presented of the various sequelae of otitis media with effusion under the basic concept of the atelectatic ear because most of the sequelae observed had developed through the atelectatic ear. This classification depends on localization of the main pathology, i.e. the tympanic membrane, middle ear or inner ear.

Adolescent↗
PubMed1985

Computed tomographic features in muco-pyoceles of the maxillary sinus.

Radiological images of muco-pyoceles of the maxillary sinus often simulate those of malignancy. This presents a diagnostic dilemma for rhinologists. The authors studied the computed tomographic findings of 13 cases of muco-pyoceles of the maxillary sinus by obtaining two different images, one of the soft tissues and the other of the bony structures. The bony sinus walls are distended and thinned in many cases by long-standing intramural pressure. The most reliable finding in the diagnosis of muco-pyoceles is the smooth clear-cut margins of bone erosions occurring in the sinus walls.

Adult↗
PubMed1984

Effects of keratin on bone resorption in experimental otitis media.

Keratin debris is a constant feature in middle-ear cholesteatoma. Keratin prepared from rat skin induced a foreign-body granuloma in the subcutaneous space in the rat. In vitro this granuloma produced high levels of bone-resorbing factors: prostaglandin E2, osteoclast-activating factor, and leucine aminopeptidase. In the in vivo study, keratin-induced granuloma in the rat middle ear caused partial resorption of the cochlear wall. Macrophages, fibroblasts, and osteoclastlike cells were found at bone-resorption areas. These cells appeared to be responsible for bone resorption through production of prostaglandin E2, osteoclast-activating factor, and proteases.

Animals↗
PubMed1982

Fronto-ethmoidal mucocele--observation of its mode of enlargement.

From a study of the roentgenographic findings of fronto-ethmoidal mucoceles and anatomical specimens of the paranasal sinuses the authors surmised that many of the fronto-ethmoidal mucocele probably originate either in one of the deeply seated supra-orbital frontal or ethmoidal recesses, or in an ethmoid cell whose ostium has been obstructed by postoperative, post-traumatic or post-inflammatory osteoneogenesis or cicatrization. When isolated, the cell with secreting mucosa would increase its cavity slowly but steadily, and eventually blocks the naso-frontal duct from without. The characteristic localization of the mucoceles, frequent erosion of the superomedial wall of the orbit with inferolateral displacement of the globe, our roentgenographic findings of a mucocele within the frontal sinus, pseudostratified columnar epithelium that lines the mucocele, occasional multilocularity, and the long interval, over ten years, that is required for the mucocele to show any symptoms in most instances would support this hypothesis.

Adult↗