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Biomedical subjects

K Fujihara

Publications and source records attributed to K Fujihara.

68 records · Page 4Linked to original sources
PubMed1991

Cellular immune surveillance against HTLV-I infected T lymphocytes in HTLV-I associated myelopathy/tropical spastic paraparesis (HAM/TSP).

To investigate the cellular immune surveillance against HTLV-I infected T lymphocytes in HTLV-I associated myelopathy/tropical spastic paraparesis (HAM/TSP), we studied the cytotoxic T lymphocytes (CTL) activity against an HTLV-I infected human T cell line (MT-2) and the natural killer (NK) cell activity in 15 HAM patients, 6 HTLV-I carriers, and 15 controls. The activity of CTL against MT-2 cells was found to be significantly elevated in HAM compared with that in the controls. This cytotoxicity in HAM was higher than in HTLV-I carriers, although the difference was not statistically significant. There was an HLA class I restriction in this CTL activity against MT-2 cells in HAM. On the other hand, NK cell activity was significantly lower in HAM than in controls. Cold target inhibition studies suggested that NK cells could not lyse MT-2 cells effectively. There was a positive correlation between the CTL activity against MT-2 cells and the serum antibody titers to HTLV-I in HAM.

Adult↗
PubMed1991

Leukoencephalopathy in HTLV-I-associated myelopathy/tropical spastic paraparesis: MRI analysis and a two year follow-up study after corticosteroid therapy.

Magnetic resonance imaging (MRI) of the brain was studied in 35 patients with HTLV-I-associated myelopathy (HAM)/tropical spastic paraparesis (TSP), 19 HTLV-I seropositive carriers without HAM/TSP (non-HAM/TSP carriers), 18 patients with HTLV-I seronegative spastic spinal paraparesis (SSP), and 82 HTLV-I seronegative controls with other neurological disorders. The incidence of white matter lesions was significantly higher in HAM/TSP (66%) than in the controls (23%) and SSP (11%). HAM/TSP exceeded non-HAM/TSP carriers significantly in the incidence of multiple white matter lesions (37% vs 10%). HAM/TSP affected the deep and subcortical cerebral white matter multifocally, sparing the periventricular regions. None of the lesions were enhanced by gadolinium-DTPA. HAM/TSP patients with the white matter lesions had both a longer duration of disease and a greater disability than did those without lesions. The white matter lesions gradually increased in number, as the disability status became worse, in spite of the high dose corticosteroid treatment. All these observations suggest that the MRI abnormalities of the HAM/TSP brain may reflect the chronic perivascular inflammation with progressive gliosis (chronic disseminated encephalomyelitis). We propose that brain MRI can be successfully utilized as a reliable and non-invasive measure for following the disease progression in HAM/TSP.

Age Factors↗
PubMed1991

Natural killer (NK) cells in HTLV-I-associated myelopathy/tropical spastic paraparesis-decrease in NK cell subset populations and activity in HTLV-I seropositive individuals.

We examined natural killer (NK) cell activity and NK cell subset populations in 18 patients with HTLV-I associated myelopathy (HAM)/tropical spastic paraparesis (TSP), ten HTLV-I seropositive asymptomatic carriers and 20 seronegative healthy controls. The NK cell activity was significantly decreased in HAM/TSP, compared with that in controls. The percentages of NK cell subsets, such as CD16+, CD11b+, CD56+, CD16+ CD56-, CD16-CD56+, CD16+CD8-, or CD16+CD3+ cells were significantly decreased in HAM/TSP patients. Of particular interest is that the percentage of CD16+CD3+ cells, which have a wide spectrum of cytotoxic properties commonly seen in NK, lymphokine activated killer (LAK) and antibody-dependent cellular-cytotoxic (ADCC) effector cells, was significantly decreased in HAM/TSP as compared to asymptomatic carriers as well as controls. The percentage of CD16+CD3+ cells correlated inversely with the value of spontaneous proliferation of peripheral blood lymphocytes (SPP), which is a characteristic change observed in HAM/TSP.

Adult↗
PubMed1991

[A study on the tonsil with focal infections--with special reference to the newly devised tonsillar cryptscope and the architecture of vessels in crypts].

It is well known that inflamed human palatine tonsils have many surface crypts showing characteristic lymphoepithelial symbiosis, which play an important role in immune response. The cryptepithelia are rich in blood vessels. This proliferation of blood vessels is said to be the initiation of various kinds of immune responses. We devised a tonsillar cryptscope in order to observe the tonsillar crypt. Scopy with the cryptscope confirmed seven characteristic types of capillary vessels. The cryptscopic figures showed different patterns in tonsillar diseases such as hypertrophic tonsil, recurrent tonsillitis and tonsil with focal infection (palmoplantar pustulosis and psoriasis vulgaris). In this study the significances of tonsillar cryptscopic figures were investigated through the study of three dimensional structures of blood vessels and immuno-histology. In order to understand the structure of capillary vessels in details, human palatine tonsils were studied using corrosion casting techniques with a scanning electron microscope. Horseshoe type capillary vessels corresponded to the curved capillary vessels in the epithelium. This type of capillary vessel was observed in the epithelia covering the interfollicular area. The tonsillar blood vessels, along with closely related substances in the epithelium and the parenchyma, were immuno-histologically examined. Where the lymphocytes had densely infiltrated the epithelium, the basement membrane became thickened and often disrupted; the endothelial cells were also enlarged. Adrian et al reported that lymphocytes invaded from the capillary vessels within the epithelia. Thus it was suggested that the horseshoe type was related to lymphocyte invasion of the epithelia.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

[Tetany as a sole manifestation in a patient with Bartter's syndrome and a successful treatment with indomethacin].

37 year-old man presented to our clinic because of tetany that occurred during driving a car in the morning. He had no anorexia, chronic diarrhea or vomiting. He was normotensive and no edema was noted. On neurological examination, he was rather apprehensive and Trousseau sign was mildly positive. No muscle weakness was noted except for the moderate atrophies of bilateral anterior tibial muscles as a sequela of Guillain-Barré syndrome that he suffered at the age of 7. The results of laboratory studies included hypokalemia, metabolic alkalosis, hyperuricemia, increased plasma renin activity, increased plasma aldosterone concentration, reduced pressor response to infusion of angiotensin II. Based on these clinical and laboratory findings, the diagnosis of Bartter's syndrome was made. As far as we know, it is extremely rare that Bartter's syndrome manifests tetany alone as in the present case. The exacerbation of preexisting alkalosis by hyperventilation during driving might be the cause of tetany. Tetany was easily provoked by hyperventilation, during which serum ionized calcium remained in normal level despite the exacerbation of alkalosis. The results suggest that alkalosis per se can cause tetany in Bartter's syndrome. Indomethacin, 75 mg daily, effectively prevented tetany from recurring for nearly 4 years without any side effect.

Adult↗
PubMed1988

An architecture of capillary vessels of the palatine tonsils studied by scanning electron microscope--with special references to comparison with the tonsillar cryptscopic images.

The three-dimensional structure of capillary vessels in the human palatine tonsil using corrosion casting techniques was investigated and compared to recently developed cryptscopic images. The postcapillary venules and arterioles were distinguishable from the nuclear impressions on their walls. The configuration of vessels around the micropores of crypts is similar to the images from the cryptscope.

Capillaries↗
PubMed1983

[A case of malignant reticulosis with pericardial effusion and central nervous system involvement].

A 64-year-old man was admitted with complaints of lethargy, malaise, weight loss and transient left-hemiplegia and aphasia. Initial physical and laboratory findings showed splenomegaly and pericardial effusion. During his hospital stay, his mental status deteriorated progressively. The characteristic pathology of malignant reticulosis was noted at autopsy. Microscopic examination of the brain demonstrated accumulations of malignant histiocytic cells confined within small vessels and subsequent multiple hemorrhages and necroses in the gray matter. Malignant reticulosis with antemortem manifestations of pericardial effusion and central nervous system involvement is rare.

Brain Neoplasms↗
PubMedDate not supplied

HTLV-associated diseases: human retroviral infection and cutaneous T-cell lymphomas.

An array of neurologic, oncologic, and autoimmune disorders are associated with infection with the human pathogenic retroviruses human T-cell leukemia virus types I and II (HTLV-I, II), as well as the human immunodeficiency viruses (HIV). The cutaneous T-cell lymphomas, mycosis fungoides (MF) and its hematogenous variant Sezary Syndrome (SS), share similar clinical and pathological features to HTLV-I-associated adult T-cell leukemia (ATL) and speculation of a retroviral link to MF and SS, especially in areas non-endemic for ATL, has lead to an intensified search for HTLV- and HIV-like agents in these diseases. To further explore a potential role for human retroviruses in MF and SS, skin biopsy-derived or peripheral blood mononuclear cell-derived DNA from 17 patients (MF, n = 7; erythrodermic MF (EMF), n = 5; SS, n = 5) from the North Eastern United States were screened using gene amplification by PCR and a liquid hybridization detection assay. Previously published primers and probes for HTLV-I (LTR, gag, pol, env, and pX), and our own primers and probes for HTLV-I (gag, pol, and env), HTLV-II (pol and env) and HIV-I (gag and pol) were employed. Serum antibodies to HTLV-I were negative in all but one EMF patient. The single HTLV-I seropositive patient carrying a diagnosis of EMF generated positive amplified signals for all of the eight HTLV-I regions tested. Ultimately, this individual evolved to exhibit clinical manifestations indistinguishable from ATL. The other 16 patients were negative for all 12 HTLV and HIV retroviral regions. Our findings suggest that none of the known prototypic human retroviruses are associated with seronegative MF and SS. The uniformly positive results for HTLV-I in the seropositive patient suggests that this patient initially presented with a smoldering form of ATL and illustrates the difficulty that sometimes may be encountered in the differential diagnosis of MF, SS, and ATL based solely on clinical and histopathological criteria.

Adult↗