Biomedical subjects
Publications and source records attributed to T Masuzawa.
We present the second reported patient with cerebral endometriosis. She had repetitive partial seizures on the first day of her menstrual cycle. The seizures were controlled by danazol after the causative lesions were surgically removed.
Induction of single strand breaks in DNA was assessed by the conversion of supercoiled closed circular plasmid DNA into the open circular form. Euflavine produced single-strand breaks following irradiation but not in the control maintained in the dark. The single strand breaking activity of photoactivated euflavine was found to be dose-dependent. The effective dose conversion 50% (ED50) of the closed circular DNA to the open circular form was 0.53 microM. A comparison of 8 acridine compounds revealed that the ED50 of diaminoacridines such as euflavine, proflavine and acridine yellow or the 3,6-dimethylamino-derivative (acridine orange) was less than 1 microM while the ED50 values of the other acridines were greater than 80 microM. Euflavine was markedly inhibited by singlet oxygen scavengers such as NaN3, histidine, alpha-tocopherol or beta-carotene and partly inhibited by superoxide dismutase, mannitol or catalase. These results suggest that enflavine induces single strand breaks in DNA mainly by a type II photodynamic mechanism. Photodynamic single strand breaking activities appeared related to their mutagenic activities on yeast. This experimental system described here is useful for the quantitative assessment of the single strand breaking activities of various photosensitizers in vitro and for the determination of active oxygen species involved in those processes.
The mitogenicity of chemically synthesized lipid A analogs, 2,3-acyloxyacylglucosamine-4-phosphate (A-103) and 2,3-acyloxyacylgalactosamine-4-phosphate (A-113), was compared. Synthetic lipid A analogs of the disaccharide-type (506), the monosaccharide-type (A-103) suspended in RPMI-1640 medium supplemented with triethylamine, and Salmonella typhimurium LT-2 lipopolysaccharide (LPS) were capable of increasing the incorporation of [3H]thymidine into splenocytes of C57BL/6 mice at various doses ranging from 1.0 to 100 micrograms/ml. However, the mitogenic activity of A-113 at these doses was markedly weaker than the activity of the above materials. When the A-103 and A-113 were suspended in RPMI-1640 medium supplemented with ethanol, the mitogenic activity of A-113 also showed lower activity than that of A-103 in the splenocytes of C57BL/6 mice. These findings indicate that the mitogenic activity of synthetic lipid A of the monosaccharide-type is affected by a kind of composed sugar.
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A case of arteriovenous malformation (AVM) with cyst formation is reported. A 14-year-old girl was admitted to our hospital, complaining of headache. On admission, CT scan showed a cystic mass with mural nodule in the right parietal lobe. Contrast enhanced CT scan demonstrated homogeneous enhancement of the nodule. MRI demonstrated the nodule as an area of signal void. Right carotid angiogram showed a typical nidus with feeding artery and draining vein. The nidus was totally removed by the trans-cystic approach. Histological diagnosis was typical AVM with hemosiderin deposits. AVM with cyst formation is very rare, with only six cases having been reported. The mechanism of cyst formation is controversial. Past reports have hypothesized the participation of a massive hemorrhage, or exudative process. Our case showed hemosiderin deposits, but no symptom indicative of hemorrhage. In this case, the etiology of cyst formation was considered to be exudation and thrombosis of the nidus.
We reported a 6-month-old boy, patient of hypothalamic hamartoma with a rare association of poly- and syndactyly, which developed gelastic seizures and precocious puberty. His birth was complicated by poly- and syndactyly in both hands and polydactyly in both feet, but other physical signs were normal. At 5 month of age, he visited our hospital because of a suspected seizure. On admission, physical and neurological examinations revealed increased size in penis and testes, and delayed psychomotor development. Gelastic seizures occurred up to 100 times a day, and were resistant to many anticonvulsants. Ictal EEG showed bursts of generalized high voltage slow waves. His serum LH and testosterone levels were elevated for his age. Brain CT and MRI demonstrated a hypothalamic mass lesion, which proved to be hamartoma by biopsy.
The present cross-sectional study was carried out to determine the influence of oophorectomy (OPX) on serum levels of sex steroids and bone metabolism, as well as bone mineral density (BMD), in OPX subjects in comparison with age- and body size-matched controls. Quantitative computed tomography (QCT) and dual-photon absorptiometry (DPA) demonstrated a remarkable reduction in BMD in OPX subjects. In particular, the QCT of the centrum of vertebral bone (QCT-C) in these subjects was no more than 69.33 +/- 3.40% (X +/- SEM) of the control value, and this parameter was much lower than the QCT integral (QCT-I) value of total lumbar vertebrae. This means that BMD decreases specifically in spongy portions after OPX. The serum level of estrone (E1) was significantly lower in OPX subjects than in controls. The hormonal action of E1 on target organs has been thought to be only one-third of that of estradiol (E2), but the marked reduction in serum E1 level seemed to be a significant cause of the reduction in BMD. The serum level of androstenedione (delta 4) significantly decreased in OPX subjects and appeared to affect bone metabolism negatively. Both bone formation and bone resorption were found to be stimulated following OPX, but the rate of bone resorption was found to be higher than that of bone formation: there was an imbalance between bone formation and bone resorption in OPX subjects. However, it was not possible to prove a relationship between Ca regulating hormone and this phenomenon. In conclusion, the QCT-C value reflects the changes in spongy vertebral BMD more sensitively than the QCT-I value or DPA.(ABSTRACT TRUNCATED AT 250 WORDS)
The distribution of neurofilament (NF) proteins was studied immunohistochemically in the gerbil hippocampus with antibodies against NF68 (68 Kd molecular weight) and NF200 proteins, and changes in the distribution of NF proteins after transient ischemia were observed in order to investigate the temporal correlation between NF and delayed neuronal death. In the normal hippocampus, NF68-like immunoreactivity (NF68-LI) was densely distributed in nerve processes in CA2, CA3 and the hilus of the dentate gyrus but was less intense in CA1. In contrast, processes with NF200-LI appeared to be evenly distributed in CA1, CA2, CA3 and the dentate gyrus. Mongolian gerbils were subjected to transient ischemia for 5 min by bilateral carotid occlusion and subjected to immunohistochemistry 1, 2, 3 and 4 days after ischemia. Following transient ischemia, prior to neuronal cell death, the intensity of both NF68-LI and NF200-LI decreased in the whole hippocampal formation. This decrease was more obvious in the case of NF68-LI than NF200-LI. Four days after ischemia, when neuronal death of CA1 pyramidal cells had occurred, processes in CA1, particularly 68 Kd components, showed marked decreases in number and staining intensity, although processes in most layers of CA2, CA3 and the dentate gyrus appeared to be stained similarly to normal brain. Since NF68 protein is considered to be the major component of NF proteins and NF200 is an associated accessory protein, the current observations suggest that the poor distribution of NF68 in CA1 and the early loss of NF proteins may be closely related to selective vulnerability of CA1 pyramidal cells and delayed neuronal death.
A cardiovascular system model that simulates interactive responses to drugs has been developed on a small digital computer. The overall model basically consists of three models. The first is a momentum transport model that represents relations between blood pressure and flow in the cardiovascular system. In this model, the cardiovascular system is divided into 14 components and modeled by using equivalent electrical circuits. The second is a mass transport model comprising 14 compartments corresponding to the respective components of the cardiovascular system. This model represents the distribution of the administered drug in the various cardiovascular components. The third is an interaction model that represents the relationships between the momentum and mass transport models. This model causes variations in the resistance and capacitance parameters of the momentum transport model as a function of the current drug concentrations in the appropriate compartments of the mass transport model. The capacitances representing the ventricles are varied in a time-dependent fashion to simulate the beat of the heart. Simulation is performed by using the Euler method to solve a system of 28 ordinary differential equations governing the momentum and mass transport models on a 32-bit microcomputer, a Macintosh II. The model was assessed by performing two demonstrations of the cardiovascular response to the vasopressor angiotensin II (AT II). They first examined the interaction between the cardiovascular system and AT II. The effect of AT II on the cardiovascular system was incorporated into the interaction model. Administration of AT II as a constant infusion (200 micrograms/hr) resulted in an elevation of mean arterial pressure from approximately 100 to 150 mm Hg.(ABSTRACT TRUNCATED AT 250 WORDS)
An immunohistochemical method was used to study the distribution and changes with time of the astrocytic reaction in the gerbil hippocampus following transient ischemia. Three markers were investigated with specific antibodies to glial fibrillary acidic protein (GFAP), glutamine synthetase (GS), and S-100 protein. On Day 2 after ischemia, and more prominently on Day 3, reactive astrocytes were intensely stained for GFAP in the hippocampal formation, especially in the CA1 region and dentate gyrus. This response by astrocytes preceded CA1 pyramidal cell degeneration, which became apparent on Day 5. On Day 5, immunoreactive cells were not stained as intensely as on Day 3, but cells in the CA1 region and dentate gyrus were still more intensely stained than those in normal animals. GS and S-100 showed similar changes in distribution after ischemia, although the change in GS was less prominent: the hilus of the dentate gyrus was most intensely stained. Both immunoreactivities seemed to increase rather transiently on Day 2 or 3 and to decrease to the initial level on Day 5. The fact that reactive astrocytes appeared in CA1 before the onset of visible neural degeneration indicates that signals from indisposed neurons may be transmitted to astrocytes for their quick functioning. It is also suggested that degenerative changes occur in the dentate gyrus and may be involved in the delayed neural death of CA1 pyramidal cells. These observations indicate that astrocytes play a role in the neural degeneration induced by ischemia and that several types of astrocytes seem to react differently.
A rare case of medulla oblongata germinoma in a 19-year-old Japanese man with Klinefelter syndrome is presented. Light microscopic examination of the resected specimen showed very few lymphocytes, and an immunohistochemical study for placental alkaline phosphatase was of great diagnostic value. Up to now there have been only five cases of intracranial germ cell tumors in association with Klinefelter syndrome. These tumors were situated along in the midline structure. It is emphasized that endocrinological factors at the time of embryogenesis as well as a genetic malignant potential are important in the pathogenesis of extragonadal germ cell tumors associated with Klinefelter syndrome.
The present study was designed to investigate in a comparative manner whether menopause or oophorectomy (OPX) would be a more osteoporosis-inducing factor with regard to sex steroids, bone metabolism and bone mineral density (BMD), including postmenopausal subjects, OPX subjects and age- and body-size-matched premenopausal controls. Serum levels of estradiol (E2), testosterone (TS) and dehydroepiandrosterone (DHEA) were found to decrease in both the postmenopausal and OPX subjects without any significant difference between them, while serum levels of estrone (E1) and androstenedione (delta 4), which have been reported to be related to bone metabolism, were significantly lower in the OPX subjects than in the postmenopausal subjects. According to the indices representing bone formation and bone resorption, as well as the changes in serum levels of Ca-regulating hormones, bone metabolic balance seemed to be slightly more negative in the former than in the latter. However, there was no difference between these two groups of subjects with regard to BMD in lumbar vertebral spongy portion which sensitively reflects the changes in total lumbar BMD and bone metabolism and in which compressive fracture is apt to occur. This fact suggests that these two groups of subjects may be managed in the same way in clinical practice. In other terms, the menopause, a natural event in women, influences BMD as much as OPX, which is the greatest risk factor in osteoporosis, does.
Slices were made from the hippocampus of gerbils following transient ischemia achieved by clamping the carotid arteries for 5 min, and changes in the electrophysiology of CA1 pyramidal neurons were studied by whole cell patch-clamp recording as well as conventional intracellular recording. The great majority of CA1 neurons in slices made 2.5-3 days after ischemia showed reduced resting potentials and were easily depolarized by prolonged low-frequency stimulation or by tetanic stimulation of the Schaffer collateral/commissural input. This stimulus-induced depolarization was accelerated by intracellular injection of D-myo-inositol 1,4,5-triphosphate, which depolarized membrane potentials towards 0 mV without synaptic input stimulation. Intracellular application of BAPTA, a Ca2+ chelator, effectively blocked the stimulus-induced depolarization. When recording from ischemic neurons with patch pipettes containing both D-myo-inositol 1,4,5-triphosphate and BAPTA, excitatory postsynaptic currents were transiently potentiated by stimulation, but the membrane potential did not show stimulus-induced depolarization and remained steady for long periods. These results lend support to the view that the intracellular Ca2+ regulation system is severely disturbed following ischemia, and that input fiber stimulation leads to abnormal Ca2+ accumulation in ischemic neurons resulted in neuronal death. The reduction of free Ca2+ inside the ischemic neuron by BAPTA apparently saves neurons which are otherwise destined to delayed neuronal death.
Antibody to Borrelia burgdorferi was examined in 380 healthy and 38 clinical cases of cows from Hokkaido and Shizuoka in Japan. In healthy animals, IgG and IgM antibody to B. burgdorferi HO14 strain were found in 44 cows (14.6%) and 24 cows (8.0%) from Hokkaido. In contrast, antibody-positive case was not observed except for only 1 case which was IgM positive (1/79: 1.3%) in cows from Shizuoka. Mean antibody levels of healthy animals in Hokkaido and Shizuoka were 0.651 and 0.263 (IgG antibody to HO14 strain), 0.642 and 0.169 (IgG to HP3 strain), 0.613 and 0.367 (IgM to HO14 strain) and 0.582 and 0.286 (IgM to HP3 strain). The differences of the antibody levels between cows from Hokkaido and Shizuoka were significant. Seasonal difference was found in seropositive cows from Hokkaido. The rate of seropositive cows was high in summer (23.4% in June and 11.8% in July) but low in winter (0% in January and February). The pattern was discussed to be associated with activation of ticks. One of 4 cows with arthritis showed significantly higher IgG antibody level than that of healthy cows and cows with some disease, although the serum was collected from Shizuoka where antibody-positive animals for B. burgdorferi were rare among healthy cows. This high IgG antibody may suggest that the arthritis of such cows was caused by infection with B. burgdorferi. Two of 7 cows with unclassified abortion showed positive antibody reaction in Hokkaido. These cases, however, may not be related to the B. burgdorferi infection because the positive rate was similar to those of healthy cows in the same season.
Infectivity of Borrelia burgdorferi strain 297 in normal outbred ddY mice was examined. Strain 297 was inoculated intraperitoneally in 3-week-old outbred ddY mice. B. burgdorferi was routinely cultured from the heart and urinary bladder 5 to 84 days postinoculation. The combined isolation rate from both heart and urinary bladder was significantly higher than the rate from spleen, kidney, liver, urine, and blood samples. Three- and 10-week-old mice were infected with inocula of 10(4) and 10(5) or more, respectively. Passive transfer of undiluted and 10-fold-diluted anti-297 rabbit serum and active immunization of 50 to 100 micrograms of lyophilized whole cells completely protected mice from infection with B. burgdorferi. These results suggest that the outbred mouse is a convenient model for experimental infection with B. burgdorferi.
Three cell lines producing monoclonal antibodies, Az-1 (IgG1), Az-2 (IgG1) and Az-3 (IgM) against aztreonam were established. The epitopes and the cross-reactions of the antibodies with various beta-lactams, which were conjugated with human serum albumin (HSA), were examined by enzyme-linked immunosorbent assay (ELISA) and ELISA inhibition test. In ELISA, Az-1 and Az-2 reacted only with aztreonam and ceftazidime, which have the same acyl side chain. Furthermore, Az-2 showed a strong cross-reaction with carumonam. In the ELISA inhibition test, Az-1 and Az-2 were inhibited from binding to aztreonam-HSA by aztreonam, ceftazidime, aztreonam hydrolysate, aztreonam-epsilon-amino-n-caproic acid (EACA) and ceftazidime-EACA. Az-2 was also inhibited with carumonam. From the above results, it seems that Az-1 can recognize only the degraded structure of monobactam nucleus, and Az-2 can recognize the degraded nucleus moiety and the acyl side chain. On the other hand, Az-3 displayed broad cross-reaction to various beta-lactams in ELISA. Furthermore, the MAb showed no inhibitory reaction with various beta-lactams except aztreonam- and ceftazidime-EACA conjugates in the ELISA inhibition test, suggesting that Az-3 recognize a new antigenic determinant (NAD), which is formed by the conjugation of beta-lactam and carrier protein. The above results indicate that antibodies can recognize at least three epitopes of the degraded product(s) of aztreonam nucleus, acyl side chain and NAD in aztreonam-protein conjugate.
Lymphocytic adenohypophysitis is a rare inflammatory disorder of the anterior pituitary gland. In some cases, there is evidence of concurrent autoimmune disease. We present the case of a 39-year-old woman who developed visual disturbance during the early postpartum period. Magnetic resonance imaging revealed an intrasellar mass with suprasellar extension. Study of the tumor tissue showed diffuse infiltration of the entire pituitary gland by lymphocytes and plasma cells. Immunohistochemical examination revealed that the majority of the infiltrating lymphocytes were T cells that might have modulated the immunoreaction to the anterior pituitary gland. We suggest that the disorder is related to cell-mediated immunity as well as humoral immunity.
The protective antigens (PAgs), glycolipid substance, were extracted from Leptospira interrogans serovars autumnalis, hebdomadis, australis and copenhageni, which were considered as main causal serovars of human leptospirosis in Japan, with chloroform-methanol-water (1:2:0.8, [vol/vol/vol]) solution. The tetra-valent formalin-inactivated leptospiral vaccine (Weil's disease and Akiyami combined vaccine) composed of the four serovars mentioned are used as vaccine to protect human from leptospiral infection in Japan. The protective effect, agglutinating antibody-inducing activity and opsonin-inducing activity of tetra-valent PAgs were compared with those of vaccines now in use, which were supplied by two companies, Takeda Chemical Industries, Ltd., and Denka-Seiken Co., in Japan. The tetra-valent PAgs which contained 10 micrograms of each PAg protected hamsters and cyclophosphamide-treated mice from lethal infection of serovar copenhageni and induced agglutinating antibodies against the four serovars in the same degrees as vaccines. These results suggested that the tetra-valent PAgs might be useful as a component vaccine against leptospiral infection instead of formalized whole cells vaccines for human.