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Biomedical subjects

M Osame

Publications and source records attributed to M Osame.

At least 343 records · Page 19Linked to original sources
PubMed1992

Cell surface phenotype of in vitro proliferating lymphocytes in HTLV-I-associated myelopathy (HAM/TSP).

The in vitro proliferation of peripheral blood lymphocytes (PBLs) without any mitogenic stimulation is one of the hallmarks of human T lymphotropic virus type I (HTLV-I) infection. Recent evidence suggests a difference in the degree of the phenomenon between HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and asymptomatic HTLV-I carriers (AC). In this article, we demonstrated several alterations in the features of the in vitro transformed lymphocytes between patients with HAM/TSP (n = 16) and AC (n = 8). The percentages of total CD8+ and CD8+CD28+ cells were significantly increased in the in vitro proliferating T lymphocytes derived from the patients with HAM/TSP when compared to those from AC. HAM/TSP was segregated from AC by the high degree of the proliferation of CD8+CD28+ cells. The expression of HTLV-I-specific antigens on the cultured PBLs was detected only in the subjects which showed low CD8+CD28+/CD4+ ratio of the in vitro proliferating lymphocytes. These findings suggest that this phenomenon distinguishes HAM/TSP from AC, not only in quantity but also in quality.

Adult↗
PubMed1992

Mimicry between HTLV-I and myelin basic protein: no response in HTLV-I-associated myelopathy patients.

The reactivity to a peptide from the HTLV-I polyprotein (FKLPGLNSR) and a similar sequence from myelin basic protein (MBP) (FKLGGRDSR) was examined in relation to the proposal that mimicry of MBP by HTLV-I could be involved in autoimmune responses in HTLV-I-associated myelopathy (HAM). It was found that rabbit antibodies raised against the HTLV-I peptide recognised both peptides, with a titre of 1/10240 to the HTLV-I peptide and 1/5220 to the MBP peptide. Human sera from HAM patients and a HTLV-I carrier without HAM showed slightly higher responses to the HTLV-I peptide compared to the responses from uninfected human sera. HAM patients had greater responses to the HTLV-I peptide than to the similar MBP peptide and an unrelated bovine MBP peptide. There was no recognition of the peptides by peripheral blood lymphocytes from HAM patients or a HTLV-I carrier without HAM. It was concluded that although cross-reactivity was demonstrated in rabbits and the HTLV-I peptide was recognised by sera from HAM patients, the epitope does not appear to evoke a mimicking response to the similar region in MBP. Hence it is not likely to be involved in the pathogenesis of HAM through molecular mimicry.

Amino Acid Sequence↗
PubMed1992

Geographical subtypes demonstrated by RFLP following PCR in the LTR region of HTLV-I.

It has been demonstrated that specific mutations, localized in the long terminal repeat (LTR) region of HTLV-I, allowed to propose the existence of three HTLV-I subtypes. Because some of these mutations created or suppressed the restriction sites for ApaI, NdeI, DraI, SacI, MaeIII, and MaeII enzymes, these endonucleases were used for characterization of further 30 HTLV-I isolates. Seventeen proviral DNA from Japan, five from the Caribbean, one each from French Guyana, the United States, and China, two from Ivory Coast, and three from Zaire were tested. The DNA used were extracted from 26 in vivo peripheral blood mononuclear cell samples and from four cell lines obtained from two Japanese, one Chinese, and one North American patients. Digestions were performed on amplified DNA of the LTR region (nucleotides 31-768). The results confirm the existence of three subtypes of HTLV-I according to LTR sequences. Subtype I was observed only in patients from the Ivory Coast and Zaire. Subtype II was found in the patient from the French West Indies, and in 33% of the samples from Japan. Subtype III was most often observed in the Japanese but also in the Zairian patients.

Adult↗
PubMed1992

Patients with homocystinuria: high metal concentrations in hair, blood and urine.

Patients with homocystinuria excrete a large amount of metal in their urine. Homocysteine similar to penicillamine, administration to methylmercury treated rats resulted in a large amount of urinary methylmercury excretion. These results suggested that the total metal amounts in the whole body of patients with homocystinuria might be decreased. However, actually metal concentrations in hair and plasma of these patients were higher than those of normal controls. High plasma and hair metal levels are not accounted for in patients with homocystinuria. The physiological metal excretory mechanism in which small amounts of metals bind to the small, plasma molecular substances filter through the kidney and emerge in the urine is necessary for reconfirmation. Strongly perturbed metal metabolism exists in the patients with homocystinuria.

Adult↗
PubMed1992

Target epitope in the Tax protein of human T-cell leukemia virus type I recognized by class I major histocompatibility complex-restricted cytotoxic T cells.

A trans-acting regulatory gene product p40tax (Tax) of human T-cell leukemia virus type I (HTLV-I) is one of the main target antigens recognized by cytotoxic T lymphocytes (CTL) specific for HTLV-I. A CTL epitope within the Tax protein was identified in this report. HTLV-I-specific CD8+ CTL lines established from two HTLV-I carriers with HTLV-I-associated myelopathy or Sjögren syndrome were previously demonstrated to kill predominantly the target cells expressing HTLV-I Tax. The CTL from two patients showed significant levels of cytotoxicity to autologous target cells pulsed with a synthetic peptide of 24 amino acids corresponding to the amino-terminal sequences of the Tax protein. Allogeneic target cells were also sensitized for CTL by this peptide when the target cells have HLA-A2. Tax-specific cytotoxicity, detected as cytolysis of the target cells infected with vaccinia virus-HTLV-I recombinant expressing Tax protein, was almost completely inhibited by competitor cells pulsed with the synthetic peptide. This indicates that a major CTL epitope is present in this peptide. Further analysis using shorter peptides revealed that the core sequence of the CTL epitope was LLFGYPVYV at positions 11 through 19. This sequence can be aligned with the HLA-A2-specific motifs reported recently.

Amino Acid Sequence↗
PubMed1992

Electrophysiological studies in cerebrotendinous xanthomatosis.

Seven patients with cerebrotendinous xanthomatosis (CTX) were studied by electrophysiological techniques. The percentages of abnormalities detected in nerve conduction studies and electroencephalograms were 28.6% (two patients) and 100%, respectively. All patients showed prolonged central conduction times in short latency somatosensory evoked potentials (SSEPs) by tibial nerve stimulation but normal SSEPs by median nerve stimulation. Brain stem auditory evoked potentials and visual evoked potentials were abnormal in three (42.9%) and four patients (57.1%), respectively. These electrophysiological parameters were correlated with the ratio of serum cholestanol to cholesterol concentration. The results of SSEPs suggest that the polyneuropathy in CTX is caused by distal axonopathy affecting longer axons before shorter axons (central-peripheral distal axonopathy).

Adult↗
PubMed1992

Changes in serum lipoprotein(a) and C4b-binding protein levels after acute myocardial infarction.

We investigated changes in serum lipoprotein(a) (Lp(a)) and C4b-binding protein (C4bp) levels following acute myocardial infarction (AMI). Serum lipids, apolipoproteins, C-reactive protein (CRP), sialic acid and haptoglobin (Hp) were also measured and evaluated. The study involved 16 patients (11 men, 5 women, mean age 68.2 +/- 8.4 years) with AMI admitted within 12 h after the onset of illness. CRP rose sharply and immediately after the onset of AMI, reaching its maximum level on the 3rd day of illness. This was followed by temporary increases in sialic acid and Hp, both of which peaked on the 7th day of illness. The Apo A-I level was significantly lower on the 14th day, while the Apo B level was significantly lower on the 3rd day. Serum total cholesterol (T-Ch), HDL-Ch and LDL-Ch showed temporary decreases after the onset of illness. Serial examination of the serum of patients with AMI yielded the following findings; 1) Both Lp(a) and C4bp levels rose temporarily with similar patterns of variation, and 2) they took longer time to peak (around the 14th day) and lasted longer than the increases in the other acute reactive proteins.

Aged↗
PubMed1992

Risk factors in normolipidemic male patients with coronary artery disease in Japanese.

We examined serum lipids, lipoproteins, apolipoproteins (Apo), lipoprotein(a) (Lp(a)), C4b-binding protein (C4bp) and lathosterol in 22 normolipidemic (serum total cholesterol less than 220 mg/dl and serum triglycerides less than 150 mg/dl) male patients with coronary artery disease (CAD) and 33 normal male subjects. Many of the patients in the CAD group with normal total cholesterol (T-Ch) and triglycerides (TG) had higher TG, low-density lipoprotein (LDL)-Ch, beta-lipoprotein (Lipo) and Apo B values and lower high-density lipoprotein (HDL)-Ch, Apo A-I and Apo A-II values than those of the control group. Differences were also observed in the beta-Lipo/HDL-Ch, Apo B/Apo A-I, and HDL-Ch ratios and the atherogenic index [A.I. = (T-Ch--HDL-Ch)/HDL-Ch], all of which are generally accepted as indices for atherosclerosis. Even in CAD patients with normolipidemia, the HDL-Ch/T-Ch ratio and A.I. seemed to be important risk factors. In addition, Lp(a) and lathosterol, an accepted indicator of whole-body cholesterol synthesis, were higher in the CAD group. The CAD group also appeared to have a higher C4bp value, suggesting that this parameter is correlated with other lipids.

Carrier Proteins↗
PubMed1992

Ehlers-Danlos syndrome combined with von Recklinghausen neurofibromatosis.

We recently had the opportunity to study a 25-year-old male with both Ehlers-Danlos syndrome (EDS) and von Recklinghausen neurofibromatosis (VRNF). We describe the clinical manifestations of the case and discuss the probable pathomechanism of the combination of the two syndromes, with a review of the literature. As recent literature suggests that both syndromes are linked to chromosome 17, we conclude that their combination is not coincidental, but genetically linked.

Adult↗
PubMed1992

Lymphocyte subsets in muscle biopsies of human T-lymphotropic virus type I carriers with polymyositis.

Recent epidemiologic studies have shown that human T-lymphotropic virus type I (HTLV-I) is associated with polymyositis. To clarify the histological features of HTLV-I positive polymyositis, we studied muscle tissue from two groups of patients with polymyositis, those seropositive for HTLV-I (5 patients) and those seronegative (5 patients). We examined the lymphocyte subsets in muscle biopsies using monoclonal antibodies. In the endomysium, a variable number of T-lymphocytes and macrophages and a smaller proportion of B-lymphocytes were found in both groups. In both HTLV-I positive and negative patients a variable number of T-lymphocytes and macrophages, with a smaller number of B-lymphocytes, were found in the perimysium. As a whole, the T-lymphocytes were predominantly of the helper/inducer phenotype in both groups. We failed to find any specific phenotype distribution among T-cells infiltrating the muscle of HTLV-I carriers with polymyositis.

Adult↗
PubMed1992

[Adult-onset neuronal ceroid lipofuscinosis--a case report with biological study].

A 32-year-old male was admitted to our hospital complaining of dementia, gait disturbance and blindness. These symptoms developed at the early two decade and were progressive. On admission, his clinical features included dementia (IQ = 69), spasticity, accentuated deep tendon reflexes, ataxia and hypesthesias in his distal limbs. Brain CT scans showed diffuse cerebral atrophy. On light microscopy, many abnormal lipopigments resembling ceroid and lipofuscin were found in Schwann cells of sural nerve and histiocytes of colon. Ultrastructurally, these materials showed lamellar structure like Zebra bodies. Nine lysosomal enzymes, serum very long-chain fatty acids, serum amino acids and urinary oligosaccharides were all normal. Neuronal ceroid lipofuscinosis (NCL) of adult type was diagnosed on the basis of clinical features, radiological and pathological findings, and biochemical studies. Many previous studies suggested that NCL was a disorder with lysosomal dysfunction. We examined lysosomal protein degradation, using 125I-low density lipoprotein (LDL) in cultured fibroblasts from this patient. The degradation of LDL was normal, compared to control subjects. The activities of cathepsin and lysosomal glycosidases, were also normal. The amount of urinary dolichol has been reported to be elevated in the patients with infantile and late infantile types of NCL. However, no elevation was found in the urine of our patient.

Adult↗
PubMed1992

[Therapeutic effect of lymphocytapheresis on patients with HTLV-I-associated myelopathy (HAM)].

Lymphocytapheresis (LCP) was performed in 7 patients (1 male and 6 females) with HAM to delete lymphocytes from their peripheral blood, resulting in an improvement of motor disability in 6 of 7 patients with HAM. The therapeutic effect appeared within one day after first LCP, and reached maximum in 2 or 3 sessions of LCP. The side effects were only dysesthesia in 5 patients during LCP and mild leukopenia in a patient after LCP. Both of them were mild and transient. The effect of LCP continued for two to five months in 6 patients, the remaining one deteriorated in a month. In the study of T cell subsets of peripheral blood lymphocytes by flowcytometry, the CD4/8 ratio and the cell counts of CD4+ DR+, CD8+ DR+ and IL-2R positive cells were gradually decreased by LCP. These results suggest that LCP is one of the effective therapies for HAM and peripheral blood lymphocytes implicate in the pathogenesis of HAM.

Adult↗
PubMed1992

[Cerebrotendinous xanthomatosis--a case of brain MRI abnormality and osteoporosis].

A 37-year-old male with cerebrotendinous xanthomatosis showed brain abnormal MRI findings and osteoporosis. His parents had no similar symptoms. He had mental retardation since childhood. Swelling of Achilles tendons was noticed at age 28, and gait disturbance appeared at age 34. Physical examination revealed bilateral cataracts and swelling of Achilles tendons. Neurologically, he showed mental retardation, cerebellar ataxia and spastic tetraparesis. Cerebrotendinous xanthomatosis was diagnosed by marked elevations of serum cholestanol level (24.3 micrograms/ml) and cholestanol/cholesterol ratio (1.81%) as well as characteristic clinical manifestations. On brain MRI study, T2-weighted sequence showed bilateral focal lesions with high intensity signal in the globus pallidus and cerebellar white matter adjacent to the dentate nucleus, and T1-weighted sequence showed low to iso-intensity signal in the same regions. These findings suggested demyelination rather than xanthoma or lipid infiltration. Radiological examination showed mild osteoporosis of lumbar bone. However, serum levels of vitamin D3 and calcitonin were within normal range, and renal function was normal. Osteoporosis in this patient possibly resulted from disuse bone atrophy for several years. The combination therapy of oral administration of chenodeoxycholic acid and HMG-CoA reductase inhibitor (pravastatin), and LDL apheresis slightly improved EEG abnormality and gait disturbance, but not brain MRI abnormality.

Adult↗
PubMed1992

[Significance of anti-HTLV-I antibody in cerebrospinal fluid in diagnosis of HTLV-I associated myelopathy (HAM)].

Anti-HTLV-I antibody was measured in 69 cerebrospinal fluids (CSFs) of cases with typical HTLV-I associated myelopathy (HAM) and other disorders whose symptoms were similar to HAM in order to evaluate the diagnostic significance of anti-HTLV-I antibody in CSF. Both gelatin particle agglutination (PA; Serodia-ATLA) method and recombinant gag-env hybrid protein coated ELISA were employed simultaneously. Antibody titers of both methods showed linear correlation. Cases with typical HAM (24 cases) and HAM with additional neurological manifestations (7 cases) showed high positivity in both methods. Cases with other neurological disorders with possible HAM (11 cases, seropositive) and cases with other neurological disorders without HAM (12 cases, seropositive) showed low positivity with low titer in ELISA, on the other hand, 81% and 67% of those cases were positive in PA method. All cases with seronegative neuroimmunological disorders (15 cases) were negative in CSFs. These findings showed that anti-HTLV-I antibody in CSF is significant in diagnosis of HAM, and both PA and gag-env ELISA are useful to detect anti-HTLV-I antibodies in CSF.

Agglutination Tests↗
PubMed1992

Marked increase in plasma interleukin-6 in burn patients.

We measured the levels of interleukin-6 in plasma samples from 18 consecutive burn patients, including three lethal cases, during the early postburn period. In survivors burn injury caused initial increases in interleukin-6 levels that peaked at 6 hours after burn; this was significantly higher than interleukin-6 levels in normal controls (718 +/- 216 vs 70 +/- 4 pg/ml; p < 0.01). The increment in nonsurvivors was even more prominent (11,554 +/- 4,407 pg/ml; p < 0.01). The peak interleukin-6 levels at 6 hours correlated with total burn surface area (r = 0.65, p < 0.025), and tended to be higher in patients with inhalation injury. These data provide evidence that burn injury causes rapid release of interleukin-6 according to the severity of the injury. We also measured acute-phase reactants including fibrinogen, alpha 1-antitrypsin, C1 inhibitor, and alpha 2-plasmin inhibitor. After initial declines, these four proteins increased rapidly in survivors. In addition, the peak interleukin-6 levels correlated well with the increases in fibrinogen (p < 0.025), alpha 1-antitrypsin (p < 0.01), C1 inhibitor (p < 0.01), and alpha 2-plasmin inhibitor (p < 0.0001). In contrast, despite the marked increase in interleukin-6, the levels of acute phase proteins in nonsurvivors remained low. Based on these observations, we suggest that interleukin-6 is released as an alarm signal and has a role for the wound healing in burn patients, and that the levels of interleukin-6 after injury is an indicator of the severity of burn.

Acute-Phase Proteins↗
PubMed1992

[Clinical and histochemical findings in spinal muscular atrophy].

The childhood form of the spinal muscular atrophy (SMA) is classically subdivided into three groups on the basis of a combination of age of onset, milestones of development and age of survival: acute Werdning-Hoffmann (type I), intermediate Werdnig-Hoffmann (type II) and Kugelberg-Welander disease (type III). Now we examined 7 cases of type I and 9 cases of type II on clinical and histochemical ground. Of the total of 16 cases, 5 cases had a family history of the disease. (1) In type I, three were males and 4 females. The onset was within 30 days and the disease was manifest before or at delivery in 3 cases. The progression was so severe. All cases were dead by 10 months. They showed generalized hypotonia, abnormal respiration and could not sit without support. In type II, five were males and 4 females. The onset of the disease was between the age of 3 and 15 months. The progression was slow. All patients couldn't walk by themselves at all but 7 of them had abilities to sit without support. Clinically it was easy to classify type I from type II. (2) The most characteristic histochemical findings of both types were group atrophy, fiber hypertrophy, fiber type predominance and fibrosis. Though there was a slight difference between two types in histological pattern, the basis was so similar. There is controversy about the proper classification of recessive childhood SMA. Now it is suggested that the majority of both acute and chronic cases are allelic, similar to the patterns of Duchenne and Becker forms of muscular dystrophy.

Biopsy↗