Biomedical subjects

T Fukaya

Publications and source records attributed to T Fukaya.

At least 19 recordsLinked to original sources

PubMed1992

Triple cancers in the urogenital area of a patient with aplastic anemia.

Three epithelial neoplastic lesions, perineal Bowenoid papulosis, uterine cervical carcinoma, and bladder transitional cell carcinoma, which occurred in a mildly immunosuppressed patient who had aplastic anemia were studied for human papillomavirus (HPV) infection. In the Bowenoid papulosis, HPV type 16 DNA was identified by polymerase chain reaction (PCR) and by in situ hybridization (ISH). In contrast, in the uterine cervical carcinoma, HPV 16 was not detected, although possibly another unidentified type of HPV in the lesion was suggested by the ISH findings. In the bladder transitional cell carcinoma, neither papillomavirus genus-specific (PGS) antigen nor HPV DNA was found.

Adult↗

PubMed1992

Adenylate cyclase induces intracellular calcium increase in single human epidermal keratinocytes measured by fluorescence microscopy using Fura 2-AM.

Intracellular calcium ([Ca2+]i) is an important second messenger of extracellular signals to induce various cellular responses. Extracellular and intracellular Ca2+ are considered to be important for cellular differentiation and proliferation of epidermal keratinocytes. Several mechanisms which increase [Ca2+]i have been demonstrated in various tissues, but in epidermal keratinocytes these mechanisms are poorly understood. In epidermal keratinocytes the adenylate cyclase-cyclic AMP response is thought to regulate cell proliferation and differentiation. However, the series of reactions which follow the cyclic AMP response remain unknown. Beta-adrenergic agonists increase [Ca2+]i in cultured epidermal keratinocytes, and we have therefore studied whether stimulation of keratinocyte adenylate cyclase could induce [Ca2+]i increase, by using fluorescence microscopy with Fura 2-AM. Adenosine and histamine, which are known to be keratinocyte adenylate cyclase receptor agonists, induced transient [Ca2+]i increase, as did epinephrine. In addition, forskolin, a direct adenylate cyclase activator, and dibutyryl-cyclic AMP also induced an increase in [Ca2+]i. In a calcium-free medium epinephrine, adenosine, histamine and dibutyryl-cyclic AMP induced an increase in [Ca2+]i. These results suggest that cyclic AMP in human epidermal keratinocytes regulates [Ca2+]i, which is released from intracellular stores.

Adenosine↗

PubMed1992

Substance P induces intracellular calcium increase and translocation of protein kinase C in epidermis.

Substance P is a neuropeptide present in, and released from, peripheral C nerve endings. The presence of substance P-positive nerve fibres in the epidermis has been reported. We investigated the effect of substance P on the transmembrane signalling system of pig epidermal keratinocytes. Treatment of pig epidermis with substance P resulted in an increase in inositol 1,4,5-trisphosphate (IP3), and in intracellular free calcium. The treatment also resulted in translocation of protein kinase C from a cytosol to a membrane fraction. Substance P, however, did not affect the beta-adrenergic- or histamine (H2)- adenylate cyclase responses of the epidermis. Neither forskolin-induced, nor cholera toxin-induced cyclic AMP accumulation were affected by substance P treatment. These results consistent with the view that substance P stimulates phosphatidylinositol-4,5-bisphosphate (PIP2) hydrolysis of keratinocytes, resulting in IP3-Ca2+ and diacylglycerol-protein kinase C signal activation. Although protein kinase C is known to affect the epidermal adenylate cyclase system, no evidence for such 'cross-talk regulation' was detected in keratinocytes by substance P treatment.

Animals↗

PubMed1992

The spontaneous LH surge in ovarian hyperstimulation for assisted reproductive technology.

Thirty-seven patients who underwent assisted reproductive technology programme, in vitro fertilisation or embryo transfer and gamete intra-fallopian transfer, were randomised into two groups in order to evaluate frequency of premature spontaneous LH surge when stimulated with different type of hMG. An hMG (FSH:LH = 1:1) was administered for eighteen patients (group A) and the different highly purified hMG (FSH:LH = 19:1) was administered for nineteen patients (group B). Blood samples are drawn from day 3 of the cycle until hCG administration, and serum LH level are measured in the frozen samples. There were no statistical difference in the total amount of hMG used before hCG injection, days of hMG injection and the number of oocytes retrieved between two groups. The premature spontaneous LH surge occurred only one patient in group A (5.6%), but more frequent LH surge was observed in group B (42.1%) (p < 0.05). It is suggested that the different FSH/LH ratio may be the reason for the difference of the incidence of premature spontaneous LH surge.

Chorionic Gonadotropin↗

PubMed1991

Adenylate cyclase induces intracellular Ca2+ increase in single human epidermal keratinocytes of the epidermal sheet as measured by digital imaging microscopy using Fura 2-AM.

Intracellular Ca2+ ([Ca2+]i) is thought to act as a second messenger of transmembrane signalling systems. However, no measurement of [Ca2+]i has been made in intact epidermal keratinocytes. We have developed a method for measuring [Ca2+]i in human keratinocytes from pure epidermal sheet by the application of digital imaging fluorescence microscopy with the use of Fura 2-AM. Normal human pure epidermal sheets were obtained by dispase treatment. Epinephrine and salbutamol induced transient [Ca2+]i increases. Propranolol, a beta-antagonist, inhibited this response, while prazosin and yohimbine (alpha 1- and alpha 2-antagonists, respectively) did not affect the response. Histamine and adenosine, also receptor agonists of the epidermal adenylate cyclase system, induced a similar [Ca2+]i increase, as did forskolin, a direct activator of adenylate cyclase. These data coincide with those previously presented for cultured human epidermal keratinocytes, and reveal that adenylate cyclase activation induces an increase of [Ca2+]i in intact epidermal cells. This technique enables the kinetics of [Ca2+]i in various skin disorders to be investigated.

Adenosine↗

PubMed1991

HTLV-I-associated myelopathy in a patient with adult T-cell leukemia.

Disseminated erythematous papules and plaques developed in a 60-year-old man 3 years before the appearance of neurologic manifestations. A biopsy specimen of the plaque revealed Pautrier's microabscess and a dense mononuclear cell infiltration with atypical convoluted nuclei in the papillary dermis. These cells were helper/inducer T lymphocytes that expressed the interleukin 2 receptor. The patient's white blood cell count was normal, but 1% atypical lymphocytes and a high titer of anti-human T-lymphotropic virus (HTLV)-I antibody were detected in his serum. A smoldering type of adult T-cell leukemia was diagnosed. While he was being treated with PUVA, a gait disturbance developed. A high titer of anti-HTLV-I antibody, characteristic of HTLV-I-associated myelopathy, was demonstrated in his cerebrospinal fluid.

Humans↗

PubMed1991

Beta-adrenergic stimulation induces intracellular Ca++ increase in human epidermal keratinocytes.

Intracellular Ca++ ([Ca++]i) is one of the most important second messengers of extracellular signals that induce cellular responses. In epidermal keratinocytes, both extracellular and intracellular Ca++ are reported to be important to cell differentiation and proliferation. Several mechanisms that increase [Ca++]i have been elicited in various tissues; however, in epidermal keratinocytes they remain unknown. Thus, we investigated the [Ca++]i modulation in cultured human epidermal keratinocytes and the stimulation that increases the concentration. The [Ca++]i concentration of keratinocytes was increased immediately and transiently by epinephrine. Methoxamine hydrochloride and clonidine (alpha-1- and 2-adrenergic agonists) did not induce an increase in [Ca++]i. The beta-antagonist, propranolol, inhibited the [Ca++]i increase induced by epinephrine and salbutamol (a beta-2-agonist). These results reveal that the beta-adrenergic stimulation induces an immediate and transient [Ca++]i increase in human keratinocytes. Beta-adrenergic stimulation is known to induce adenylate cyclase activation, which results in cyclic AMP accumulation through stimulatory guanosine 5-triphosphate (GTP) binding proteins in the keratinocytes. Also, epinephrine is reported to inhibit cultured epidermal cell proliferation. The effect of epinephrine has been demonstrated by cyclic AMP accumulation; however, beta-adrenergic stimulation revealed a [Ca++]i increase in keratinocytes in our study. One of epinephrine's regulatory effects on epidermal cell proliferation is assumed to occur through the [Ca++]i increase as well.

Adrenergic beta-Antagonists↗

PubMed1991

Transient retrocochlear low-frequency sensorineural hearing loss: a new clinical entity.

Sensorineural hearing loss (SNHL) of varying types and extent developed in a number of the 963 patients who underwent microvascular decompression for hemifacial spasm. Fourteen of the patients with hearing loss had transient low-frequency SNHL. Low-frequency SNHL is seldom noted in patients with retrocochlear hearing loss, but five of these patients had Horner's syndrome or bulbar palsy. The results of Békésy audiometry, auditory brainstem response, and electrocochleography in the patients were also suggestive of brainstem pathology. Surgical records revealed that all of them had excessively short perforating arteries surrounding the entry zone of nerves VII and VIII, so that they had to be stretched during surgery. Occlusion of perforating arteries is suspected to have caused lateral brainstem infarction around the entry zone of nerves VII and VIII, and resulted in low-frequency SNHL.

Adult↗

PubMed1991

[Mouse monoclonal antibody (FKH1) detecting human melanoma-associated antigens: production, partial characterization and immunohistochemical analysis].

A mouse monoclonal antibody, FKH1, was produced to detect cytoplasmic melanoma-associated antigen. FKH1 was raised using cultured human melanoma cell line KHm-6 as immunogen. Reactivity of this antibody was assessed by immunohistochemical techniques. Positive reactions were seen against 5 human melanoma cell lines and cultured human epidermal melanocyte. It stained cytoplasm of melanoma cells in a diffuse and granular pattern with indirect immunofluorescence. Immunoelectron microscopy showed diffuse distribution of immuno-reactant in the cytoplasm of KHm-1 cells excluding melanosomes and other subcellular organelles. In immunoblotting, FKH1 bound with proteins having molecular weight of 71 kd and 55 kd extracted from KHm-6 cells. Reactivity against frozen and alcohol-fixed paraffin-embedded melanocytic tumors was also tested with indirect immunofluorescence or ABC (avidin biotin peroxidase complex) techniques. All cases of frozen sections from benign and malignant melanocytic tumors including 2 cases of amelanotic melanoma showed positive staining with FKH1. In fixed tissues, reactivity was 16/19 (84.2%) in malignant melanoma and 30/44 (68.2%) in other melanocytic tumors. FKH1 did not react against normal melanocytes, C-type nevus cell, intradermal nevus pigmentosus with neuroid structure and neurofibroma. It was demonstrated that FKH1 recognized proliferative melanocytes originated from melanoblast or melanoblastic nevoblast. FKH1 failed to stain normal human peripheral nerves and nonmelanocytic tumors except APUDoma and malignant Merkel cell tumor. In halo nevus, nevus cells were clearly distinguished from intermingling inflammatory cell infiltrate. It was suggested that FKH1 is a useful monoclonal antibody in diagnosing human malignant melanoma, particularly in evaluating tumor thickness of Breslow more precisely.

Animals↗

PubMed1990

Transient paraplegia caused by acute aortic dissection--case report.

A case of acute aortic dissection (AAD) presenting as sudden, transient paraplegia and severe back pain is reported. The patient was a 66-year-old male with a 10-year-history of hypertension. The pain characteristically migrated from the back to the neck and then returned to the back. He showed complete transverse myelopathy at the level of the 9th thoracic cord. Computed tomography disclosed internal displacement of aortic intimal calcifications, without abnormalities in the spinal canal, and myelography showed no spinal canal block or stenosis. Electrocardiography and chest x-ray indicated nonspecific changes of high amplitudes and mild cardiomegaly, respectively. Together, these findings suggested acute aortic dissection with spinal cord ischemia. The initial systolic blood pressure of 220 mmHg was lowered with medication, and the pain was controlled with morphine. He recovered fully and was discharged 80 days after the onset of symptoms, with no neurological deficits. AAD carries a very poor prognosis unless treated immediately. Therefore, it is very important to promptly differentiate this disorder from spinal vascular conditions that also produce back pain and paraparesis.

Aged↗

PubMed1979

Cross-sectional echocardiographic diagnosis of coronary artery aneurysms in patients with the mucocutaneous lymph node syndrome.

Real-time cross-sectional echocardiographic studies revealed the presence of coronary artery aneurysms in five patients with mucocutaneous lymph node syndrome. These lesions appeared as circular echo-free spaces with clearly-defined borders in sites corresponding to angiographically proven aneurysms. In 15 normal subjects who were studied only by noninvasive methods, and in 17 who had normal coronary arteriograms (including eight with the mucocutaneous lymph node syndrome), we found no similar echo findings. The aneurysms were in both right and left coronary arteries in three patients, and were confined to the left side in two. The mucocutaneous lymph node syndrome is an increasingly common condition in Japan which may be fatal due to myocardial infarction occurring in a setting of coronary aneurysm with thrombosis. Therefore, the ability to demonstrate coronary aneurysms noninvasively is of prognostic and potentially therapeutic value in this inadequately understood syndrome.

Adult↗

PubMed1979