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Biomedical subjects

A Yoshida

Publications and source records attributed to A Yoshida.

At least 433 records · Page 24Linked to original sources

Decreased heart rate variability in patients with diabetes mellitus and ischemic heart disease.

We investigated the characteristics of decreased heart rate variability (HRV) in diabetic patients with ischemic heart disease (IHD). Twenty-one healthy control subjects, 17 diabetic patients without IHD, and 33 diabetic patients with IHD were studied. The diabetic patients with IHD were subdivided into 2 groups according to the severity of their IHD: severe or mild. HRV was evaluated in all subjects using the spectral variables of the all-frequency, low-frequency, high-frequency (AF, LF, HF) components and the LF/HF ratio were determined from Holter recordings. The AF and LF components in patients with diabetes only or diabetes and severe IHD were significantly lower than in control group, but the HF component was significantly lower only in the group of patients with diabetes and severe IHD. The LF/HF ratio did not differ significantly among the 4 groups, but was the lowest in diabetic patients without IHD. Patients with diabetes and mild IHD showed a slight decrease in HRV, but this was not significant. With regard to the circadian rhythm of HRV, the AF and LF components in patients with diabetes-only or diabetes and severe IHD were significantly decreased and showed the same pattern throughout the day. However, the HF component was decreased during more time zones in patients with diabetes and severe IHD, whereas the LF/HF ratio was lower during more time zones in the diabetes-only group. All spectral variables showed a tendency to be inversely related to the duration of diabetes in all diabetic patients. In particular, the LF/HF ratio showed a significant negative correlation. The HRV of diabetic patients was characterized by a decreased LF/HF ratio. It was concluded that, although HRV in diabetic patients with severe IHD was reduced mainly as a result of diabetic neuropathy, this was also partly due to a decline in parasympathetic tone as a result of myocardial injury.

Aged↗

Enzyme immunoassay for phycocyanin as the main component of spirulina color in foods.

An enzyme immunoassay (EIA) for phycocyanin in foods was developed. Anti-phycocyanin monoclonal antibodies were obtained from A/J mice immunized with phycocyanin. The phycocyanin in a food was extracted by dissolving the sample in a borate buffer solution, pH 8.0 (BBS) and adjusting the pH value of this solution to 8.0 with NaOH. The extract was then diluted more than 10 fold with 1% gelatin in BBS. Phycocyanin was determined by avidin-biotin sandwich EIA, using the P26-8 monoclonal antibody as the solid-phase antibody and the P277-4 monoclonal antibody as the enzyme-labeled antibody. The working range for a quantitative analysis was 100-1000 ng/ml, and the detection limit was 10 micrograms/g of the original sample. Recoveries of phycocyanin from foods by this assay were > 71% for candy, and > 66% for ice cream and sherbet. Phycocyanin was assayed in 22 blue-, green-, purple-, and brown-colored commercial foods, and detected in one green colored-jelly at 49 micrograms/g.

Antibodies, Monoclonal↗

Renal handling of urate in a patient with familial juvenile gouty nephropathy.

We encountered a case of familial juvenile gouty nephropathy (FJGN) with an autosomal dominant transmission pattern. Hyperuricemia in the propositus was caused by renal underexcretion of urate although his erythrocyte purine enzyme was normal. A renal biopsy specimen from the propositus showed interstitial fibrosis with tubular atrophy. On pyrazinamide and probenecid tests, the tubular secretion of urate selectively decreased without changes in either presecretory or postsecretory reabsorption of urate when his renal function was normal. Probenecid increased the urinary urate excretion and Cur/Ccr. The serum urate concentration was poorly controlled by allopurinol. When his renal function deteriorated, the uricosuric effects of both probenecid and benzbromarone were attenuated. However, the combined administration of probenecid with allopurinol decreased the serum urate concentration. These data suggest that the tubular secretion of urate is selectively impaired in FJGN and at the stage of renal failure, the combination of an uricosuric agent with allopurinol might be effective in treating hyperuricemia in FJGN.

Adolescent↗

Transient alpha coma following minor head trauma in a patient with primitive trigeminal artery.

A 26-year-old male presented with transient alpha coma following minor head trauma after a traffic accident. His consciousness disturbance suddenly recovered 3.5 hours later. He had not suffered cardiac arrest before admission, nor was taking any drugs. Magnetic resonance (MR) angiography 6.5 hours after consciousness recovery disclosed persistent primitive trigeminal artery (PTA) with minor segmental narrowings. Three months later, MR angiography revealed that both the PTA and the distal basilar artery were slightly diated without evidence of narrowing. Conventional angiography and single photon emission computed tomography revealed that the distal basilar artery was supplied mainly by the PTA. Transient circulatory disturbance due to traumatic angiospasm of the PTA may have caused hypoperfusion of the upper brainstem in this patient.

Adult↗

Differential endothelial migration and proliferation to basic fibroblast growth factor and vascular endothelial growth factor.

Neovascularization is a feature of a variety of pathological processes. We compared the characteristics of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) on migration and proliferation of human umbilical vein endothelium (HUVEC). Both VEGF and bFGF induced endothelial cell migration at similar concentrations (1/2 max. VEGF = approximately 1.0 ng/ml, bFGF = approximately 5.0 ng/ml). However, VEGF-stimulated migration was two-fold greater than bFGF at 1 and 10 ng/ml (p < 0.05). In contrast, bFGF induced proliferation four-fold more effectively than VEGF (1/2 max. 1 ng/ml and 1.4 ng/ml respectively). Checkerboard migration assays for bFGF showed a predominantly chemokinetic pattern, whereas VEGF was predominantly chemotactic. VEGF and bFGF were not synergistic in monolayer proliferation and migration assays. Three angiogenesis inhibitors, alpha-interferon, TNP-470, and platelet factor-4, inhibited VEGF and bFGF induced cell migration. These results indicate that VEGF and bFGF are chemoattractants that stimulate endothelial migration by different mechanisms and that both can be inhibited by known angiogenesis inhibitors.

Cell Count↗

[Infection in elderly leukemic patients].

Febrile episodes occurring in 29 elderly patients (mean age 75 years) with leukemia, from 1988 to 1993, were reviewed. A febrile episode was defined as a temperature of 38 degrees C or greater for at least 6 hours. The number of febrile episodes was 64. The average was 2.2 febrile episodes per patient. Seventy-two percent of febrile episodes occurred when the patients had neutropenia below 100/microliters, while 16% occurred with neutropenia of 101/microliters to 500/microliters. Causative microorganisms were identified in 48% of total febrile episodes. The most common infectious site was the urinary tract which accounted for 25% of total episodes. Pneumonia and septicemia accounted for 22% of total episodes, respectively. Gram-positive cocci were responsible for 66% of microbiologically documented febrile episodes, while 21% were caused by gram-negative bacilli. Gram-positive cocci, particularly staphylococcus aureus, coagulae-negative staphylococcus and enterococci increased compared with a decade ago in our department. Granulocyte colony-stimulating factor (G-CSF) was used 12 times for infection. No significant difference in fever amelioration was seen between G-CSF and non-G-CFS cases.

Aged↗

Retinal blood flow changes in type I diabetes. A long-term follow-up study.

PURPOSE: The authors previously reported that blood speeds in the retinal arteries were significantly lower in patients with type I diabetes than in controls without diabetes. The purpose of this long-term, follow-up study was to characterize the natural course of changes in blood speed and blood flow in these patients. METHODS: Twenty-four patients were followed up with serial annual measurements of the blood flow in a temporal retinal artery using the bidirectional laser Doppler technique and monochromatic photography. The follow-up period ranged from 2 to 6 years (mean, 3.8 years). Using standardized color fundus photography and fluorescein angiography, a retinopathy score was generated for each eye studied. Linear regression analysis was used to compute the slope of the change in retinal blood flow for each patient during the follow-up period. RESULTS: Retinal blood flow slopes were negative in 15 patients and positive in 9 patients. Multiple linear regression analysis showed that the retinal blood flow slopes were significantly related to the retinal blood flow measured at entry to the study and to the median duration of diabetes during the follow-up period (R2 = 0.56; P = 0.0002). There was a positive correlation between the retinal blood flow slopes and the median retinopathy score during the follow-up period (P = 0.47; P = 0.02). CONCLUSIONS: As duration of diabetes becomes longer and retinopathy becomes more severe, there is a transition from negative to positive retinal blood flow slopes. This bimodal relationship between the change in retinal blood flow and the duration of diabetes reflects the complex pathologic alterations that occur in the diabetic retina.

Adult↗

[Role of the vitreous in central retinal vein occlusion].

To investigate the role of the vitreous in eyes with central retinal vein occlusion, especially in relation to neovascularization and macular edema, we conducted a retrospective chart review of the vitreous condition of 150 patients (150 eyes) with central retinal vein occlusion. Based on fluorescein angiography findings and color photographs, eyes with central retinal vein occlusion were classified as ischemic or nonischemic. In ischemic cases, retinal or optic disc neovascularization, or both, developed in eight (57%) of 14 eyes without complete posterior vitreous detachment at the final examination. The prevalence of neovascularization was significantly higher than in eyes with complete posterior vitreous detachment (0%, 0/43) at the final examination (p < 0.01). In nonischemic cases, the prevalence of no posterior vitreous detachment or partial posterior vitreous detachment with vitreomacular adhesion was significantly higher in eyes with macular edema (76%, 28/37) than in eyes without it (23%, 13/56) at the final examination (p < 0.01). Complete posterior vitreous detachment may protect against retinal or optic disc neovascularization in eyes with severe central retinal vein occlusion. Vitreomacular adhesion may cause persistent macular edema in eyes with mild central retinal vein occlusion.

Adult↗

[Fluorophotometry of the animal eye].

We assessed the usefulness of the Fluorotron Master fitted with a small animal adapter. We also discuss the measurement conditions for the tupai, which is a promising experimental mammal. A good concentration for measurements with this instrument ranged from 0.5 x 10(-6) to 1.0 x 10(-6) g/ml. A suitable time for fluorophotometry of the tupai was 30 min. after injection of fluorescein-Na, and a suitable dose of the fluorescein-Na was 2 mg/kg. We could do ultrafiltration for measurement of the protein unbound fluorescein concentration from a minimal sample of the blood using a hematocrit tube, and thus could reduce the deleterious effects of blood sampling on the animal. This instrument is useful for the estimation of the blood-ocular barrier permeability of animal models.

Animals↗

Role of serine and ICE-like proteases in induction of apoptosis by etoposide in human leukemia HL-60 cells.

This study was undertaken to examine the role of proteases in etoposide-induced apoptosis of human leukemia HL-60 cells. We found the potent activity to produce internucleosomal DNA fragmentation in a 150 000 g supernatant of cell lysate which was prepared from etoposide-treated HL-60 cells undergoing apoptosis. This nuclear-DNA fragmenting activity could be detected when the supernatant was incubated with isolated nuclei under Mg2+-dependent conditions. On the other hand, we could not detect such activity in the supernatant of cell lysate from non-treated HL-60 cells. Treatment of the supernatant with a serine protease inhibitor, N-tosyl-L-phenylala-nylchloromethyl ketone (TPCK), abolished the DNA fragmenting activity. An inhibitor of interleukin 1-beta-converting enzyme (ICE), Z-Val-Ala-Asp-fluoromethyl ketone (VAD-FMK), had no effect on this DNA fragmenting activity in vitro. However, when the cells were incubated with etoposide in the presence of VAD-FMK, the formation of TPCK-sensitive DNA fragmenting activity was blocked. Our data indicate that serine and ICE-like proteases may be involved in etoposide-induced apoptosis at the different stages, and especially a serine protease may be closely associated with the final step for induction of internucleosomal DNA fragmentation during apoptosis in HL-60 cells.

Amino Acid Chloromethyl Ketones↗

[In vitro chemosensitivity test for seven undifferentiated thyroid carcinoma cell lines using MTT assay].

In the current study, we ran a chemosensity test on 7 human undifferentiated carcinoma cell lines against 10 anticancer compounds using MTT assay. Efficacy was estimated by comparing fifty percent inhibitory concentration (IC50) with the peak plasma concentration. The results showed that the 7 cell lines could be divided into two groups which had different (high or low) chemosensitivity, and that in the high sensitivity group, ACD, VCR, and etoposide were indicated as useful drugs. Our results suggest that it may be impossible to rescue all undifferentiated carcinoma patients by chemotherapy alone because the tumor may consist of 2 clones which have a different chemosensitivity.

Antineoplastic Agents↗

Differential diagnosis of macular breaks by microperimetry using the scanning laser ophthalmoscope.

To improve the differential diagnosis of macular breaks by microperimetry using the scanning laser ophthalmoscope (SLO), we studied 50 consecutive breaks detected by biomicroscopy and indirect ophthalmoscopy. The full-thickness macular break was easily diagnosed using only biomicroscopy and indirect ophthalmoscopy because the macular break had a cuff in 22 of the eyes. SLO microperimetry also showed an absolute scotoma within the macular break and a relative scotoma on the cuff in these 22 eyes. However, in the other 28 eyes it was impossible to distinguish between the full-thickness macular breaks and pseudo-macular breaks or lamellar macular breaks using only biomicroscopy and indirect ophthalmoscopy because of the absence of a cuff. However, SLO microperimetry differentiated full-thickness macular breaks from pseudomacular breaks or lamellar macular breaks in these 28 eyes. SLO microperimetry is indispensable for determining the prognosis of and the surgical indication requirements for idiopathic macular breaks.

Diagnosis, Differential↗

[The mechanism of apoptosis induced by anticancer agents in human leukemia cells].

Many anticancer agents induce apoptosis in human leukemia cells. Among the various leukemia cells, especially HL-60 cells and U937 cells are very sensitive to apoptosis upon anticancer agents treatment. A serine protease inhibitor TPCK and an ICE-like protease inhibitor VAD-FMK prevented etoposide, camptothecin and ara-C-induced internucleosomal DNA cleavage in human myeloid leukemia HL-60 and U937 cells. Using a cell-free system, we have examined the inhibitory mechanism of these inhibitors on anticancer agent-induced internucleosomal DNA cleavage. Our data indicate that serine and ICE-like proteases may be involved in anticancer agent-induced apoptosis at the different stages, and especially a serine protease may be closely associated with the final step for induction of DNA fragmentation during apoptosis in human myeloid leukemia HL-60 and U937 cells.

Antineoplastic Agents↗

[A case of chronic tuberculous pyothorax associated malignant lymphoma].

The patient was 69-year-old male. He has a history of treatment for tuberculosis by artificial pneumothorax about 47 years ago. He was admitted an another hospital under the diagnosis of tuberculous pyothorax. He was transferred to our hospital because of chest pain and fever. Laboratory findings on the admission were as follows: ESR was 120 mm/hr, CRP was 20.22 mg/dl and other data were almost within normal limits. Chest X-ray showed a massive shadow in the right lower lung field, adjacent to the chest wall. Computed tomography (CT) showed tumor shadow with low density and invasions into the adjacent chest wall. Histological examination of surgically excised tumor biopsy revealed malignant lymphoma. The patient's condition improved and the size of tumor decreased temporarily by chemotherapy. Then, he began to complain of chest pain and high fever, and tumor in the chest wall invaded into the whole chest wall. He died of disseminated intravascular coagulation despite continuing chemotherapy. Postmortem examination revealed the following findings : the tumor existed mainly in the parietal pleura or the chest wall, adjacent to the lesion of pyothorax, and immunohistochemical examination showed that tumor was malignant lymphoma, diffuse, large B-cell type. Recent studies have shown a close association between EBV infection and pyothorax-associated lymphoma. We have to keep in mind the possible development of malignant lymphoma following tuberculous pyothorax, when we see patients complaining of fever or chest pain with tuberculous pyothorax.

Aged↗

[The mechanism of apoptosis induced by anticancer agents in human leukemia HL-60 cells].

The present study was designed to investigate the contribution of proteases in anticancer agents-induced apoptosis of human leukemia HL-60 cells. A serine protease inhibitor TPCK and an ICE-like protease inhibitor VAD-FMK prevented etoposide, camptothecin and ara-C-induced internucleosomal DNA cleavage. Using a cell-free system, we have examined the inhibitory mechanism of these inhibitors on etoposide-induced internucleosomal DNA cleavage. We found that cell lysates prepared from etoposide-treated HL-60 cells undergoing apoptosis contain the significant activity to induce internucleosomal DNA fragmentation in isolated nuclei. On the other hand, we could not detect such activity in the cell lysates from untreated HL-60 cells. Treatment of the cell lysates with a serine protease inhibitor TPCK abrogated the DNA fragmenting activity. An ICE-like protease inhibitor VAD-FMK had no effect on this DNA fragmenting activity in vitro. However, the formation of TPCK-sensitive DNA fragmenting activity in etoposide-treated cells was blocked by the VAD-FMK. These data indicate that serine and ICE-like proteases may be involved in etoposide-induced apoptosis at the different stages, and especially a serine protease may be closely associated with the final step for induction of DNA fragmentation during apoptosis in HL-60 cells.

Antineoplastic Agents↗

[MPO-ANCA positive two cases associated with interstitial pneumonitis].

We describe two cases (61-year-old female and 71-year-old male) with MPO-ANCA (myeloperoxidase-antineutrophil cytoplasmic antibody) positive who developed severe interstitial pneumonitis. They presented at our hospital with dyspnea and dry cough. The hypoxia and abnormal shadow on chest X-ray led to a diagnosis of interstitial pneumonitis. Serologic studies revealed the high titers of MPO-ANCA in two cases. They were treated with methylprednisolone, immunosuppressant agents and plasma exchange. The pneumonitis and the titers of MPO-ANCA improved on these therapies, The former was introduced continuous hemodialysis therapy and the later continued nephrotic syndrome. These renal damages did not recover, regardless of the reduction of the titers of MPO-ANCA. It is concluded that methylprednisolone pulse therapy, immunosuppressant agents and plasma exchange therapy are useful to interstitial pneumonitis in patient with positive of MPO-ANCA. The measurement of MPO-ANCA is useful to interstitial pneumonitis in patient with positive of MPO-ANCA. The measurement of MPO-ANCA is useful maker of interstitial pneumonitis for unknown causes.

Aged↗

Bucillamine induced pulmonary injury occurs with immunoglobulin decrease.

We describe pulmonary involvement in 3 patients with rheumatoid arthritis treated with bucillamine. In all 3, synovitis was in remission. The common radiological characteristic was mottled dense infiltrates, in which were air bronchograms, in the bilateral central lung, sparing the periphery. Lung biopsies in 2 cases revealed organizing exudates in the alveolar ducts and alveoli, and cellular infiltration into alveoli and septa. Serum immunoglobulin (Ig) levels decreased markedly at the time of involvement. After discontinuation of bucillamine, lung injury resolved without exacerbation of synovitis and Ig levels increased. A mechanism involving decreased Ig concentration is suggested.

Aged↗