Improved specificity of RT-PCR amplifications using nested cDNA primers.
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Biomedical subjects
Publications and source records attributed to T Kawakami.
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Double immunohistochemical staining with fluorescein isothiocyanate (FITC)- and rhodamine-conjugated antisera revealed the coexistence of substance P (SP) and calcitonin gene-related peptide (CGRP) in most nerve fibers in the intervascular stroma of the carotid labyrinth of the bullfrog, Rana catesbeiana. A few fibers contained SP without CGRP. The results suggest that the vascular regulatory function, which is one of the possible functions of the carotid labyrinth, may be controlled in part by the interaction of SP and CGRP.
The inhibitory effect of capsaicin on axoplasmic transport in cultured dorsal root ganglion cells was analyzed by video-enhanced contrast microscopy. Capsaicin inhibited particle transports in a dose-dependent manner, irrespective of the diameter of axons. The effect of capsaicin was reversible at low concentrations. Capsaicin affected both the anterograde and retrograde transport. Large organelles were more sensitive to capsaicin than small ones in the retrograde transport. An experiment using calcium-sensitive dye, Fura 2, indicated that capsaicin raised the intraneuronal free calcium concentration preceding the inhibition of the transport. Electron microscopy revealed that microtubules and neurofilaments are disorganized and disoriented by capsaicin. We reached a conclusion that capsaicin inhibits fast axoplasmic transport of both anterograde and retrograde directions in all types of somatosensory neurons in culture by disorganizing intraaxonal cytoskeletal structures, through the elevated intracellular Ca2+ concentration.
We studied the unitary distance of ATP-induced actin-myosin sliding using an in vitro force-movement assay system consisting of a myosin-coated glass microneedle and well organized actin filament arrays (actin cables) in the internodal cell of an alga Nitellopsis obtusa. The number of myosin heads interacting with actin cables was reduced to about 100, as judged from the isometric force of about 100 pN attained in the presence of 2 mM ATP. When the amount of iontophoretically applied ATP was reduced by decreasing the amount of charge passed through the ATP electrode from 80 to 2 nC, the distance of the ATP-induced actin-myosin sliding decreased almost linearly from about 100 to about 10 nm, no detectable sliding being observed with further reduction of charge through the electrode. The sliding distances with small amounts of ATP (7-16 nC) distributed around integral multiples of 10 nm, suggesting the unitary distance of actin-myosin sliding of about 10 nm.
Resistive indices (RI) in the anterior cerebral artery (ACA), basilar artery (BA), middle cerebral artery (MCA) and descending aorta (DA) were obtained in 15 small-for-dates (SFD) infants who were, growth retarded because of maternal pregnancy-induced hypertension and in 20 appropriate-for-dates (AFD) infants matched for gestational age between 24 h and 48 h after birth. The RIs in the MCA, ACA and BA were significantly lower, while the RI in the DA was significantly higher, in the SFD infants than in the AFD infants. These changes in RIs in the SFD infants might be similar to the "brain sparing" effect as reported in growth-retarded fetuses.
Gelatin capsules containing squalane partially purified bone morphogenetic protein (BMP) complex were placed on the perimuscular membrane of rats. Two kinds of control, gelatin capsules containing only BMP and those bearing squalane only, were used. The embedded areas were histopathologically examined at 3 and 6 wk after the operation. The observations revealed that the squalane/BMP complex elicited wide heterotopic bone formation with bone marrow tissue, suggesting that squalane is a possible carrier of BMP for clinical applications.
Lipoma is an uncommon tumour in the oral cavity. Infiltrating lipoma is extremely rare. An infiltrating lipoma of the mental region in a 48-year old woman is reported. Wide myectomy was performed, and follow-up showed excellent healing without recurrence.
It is widely accepted that radicular cysts (apical periodontal cysts) are commonly lined with stratified squamous epithelium without keratin formation. However, we identified a case of maxillary radicular cyst with remarkable keratinization and atypical proliferation of the lining epithelium among the 207 radicular cyst cases seen at our department. Histopathological and clinical findings of these cysts were reviewed.
To obtain information about the mechanism of ATP-dependent actin-myosin sliding responsible for muscle contraction, we studied the "unitary" distance of sliding between a myosin-coated glass microneedle and actin filament arrays (actin cables) in a giant algal cell induced by iontophoretic application of ATP, attention being focused on the minimum distance of ATP-induced sliding when the amount of applied ATP was gradually decreased in the presence of hexokinase and D-glucose. The number of myosin heads interacting with actin cables was reduced to less than 100, as judged from the maximal force Po (approximately 100 pN) generated by myosin heads on the needle in the presence of 2 mM ATP. When the amount of iontophoretically applied ATP was decreased by reducing the amount of charge passed through the ATP electrode from 80 to 2 nC, the distance of ATP-induced actin-myosin sliding decreased almost linearly from approximately 100 to approximately 10 nm, no detectable actin-myosin sliding being observed with further reduction of the charge passed through the electrode. The amount of external load exerted by the bent microneedle was less than 1% of Po for the sliding distance < 50 nm. The actin-myosin sliding distances with a small amount of ATP slightly above the amount required to induce the minimum sliding distance were distributed around integral multiples of 10 nm, suggesting that the unitary distance of actin-myosin sliding coupled with ATP hydrolysis is of the order of 10 nm.
Interferon (IFN) regulatory factor 1 (IRF-1) and IRF-2 were originally identified as transcription factors involved in the regulation of the IFN system. IRF-1 functions as a transcriptional activator, while IRF-2 represses IRF-1 function. More recently, evidence has been provided that IRF-1 and IRF-2 manifest antioncogenic and oncogenic properties, respectively, and that loss of one or both of the IRF-1 alleles may be critical for the development of human hematopoietic neoplasms. Both factors show a high degree of structural similarity in their N-terminal DNA-binding domains, and previous studies suggested that IRF-1 and IRF-2 bind to similar or identical cis elements within type I IFN (IFN-alpha and -beta) and IFN-inducible genes. However, the exact recognition sequences of these two factors have not yet been determined; hence, the spectrum of the IRF-responsive genes remains unclear. In this study, we determined the DNA sequences recognized by IRF-1 and IRF-2, using a polymerase chain reaction-assisted DNA-binding site selection method. We report that sequences selected by this method and the affinities for each sequence were virtually indistinguishable between IRF-1 and IRF-2. We confirm the presence of two contiguous IRF recognition sequences within the promoter region of the IFN-beta gene and of at least one such sequence in all of the IFN-inducible genes examined. Furthermore, we report the presence of potential IRF sequences in the upstream region of several genes involved in cell growth control.
Previous studies have shown that protein-serine/threonine kinases and protein-tyrosine kinase(s) are activated by cross-linking of the high-affinity receptor for IgE, Fc epsilon RI, on mast cells and basophils. In vitro kinase assays (ISDR kinase assays) on cellular proteins immobilized on polyvinylidene difluoride membrane after denaturation and renaturation were employed to estimate the complexity of protein kinases expressed in mouse mast cells. The results demonstrated that a large number (more than 60) of both serine/threonine- and tyrosine-specific kinases are present in a mouse mast cell line, PT-18. Cross-linking of Fc epsilon RI-induced activation of a subset of both serine/threonine kinases and tyrosine kinases in PT-18 as well as bone marrow-derived mouse mast cells, as revealed by the ISDR kinase assay. Among them, MAP kinase (or ERK2) was shown to be tyrosine phosphorylated and activated transiently upon Fc epsilon RI cross-linking, suggesting its potential role in mast cell signal transduction.
Immunoreactivities for FMRFamide and substance P (SP) in the carotid labyrinth of the bullfrog were detected using the peroxidase-antiperoxidase method, and the results compared with corresponding differential interference-contrast (Nomarski) images. Colocalization of both peptides was determined by the indirect double immunofluorescence method. Immunoreactivities for FMRFamide and SP were found in nerve fibers distributed in the intervascular stroma of the labyrinth. The FMRFamide-immunoreactive fibers were less numerous than the SP-immunoreactive fibers. In the Nomarski image, FMRFamide-fibers were recognized in relief, with most of them located near the walls of blood vessels. All FMRFamide-fibers coexisted with SP. The results suggest that FMRFamide-immunoreactive fibers are also involved in local vascular regulation of the carotid labyrinth.
We evaluated 63 patients with superficial bladder cancer (pTa, pTl) who were treated with instillation of bleomycin +/- bacillus Calmette-Guerin (BCG) and administration of uraciltfutraful (UFT) for prophylaxis of tumor recurrence after transurethral resection (TUR). The patients were randomly assigned to groups A and B after transurethral resection by the closed envelope method. Group A (34 cases) was designed as continuous diluted intravesical instillation of bleomycin (120 mg/2,000 ml saline solution/day repeated for 3 days), instillation BCG (40 mg/40 ml saline solution/weekly 6 times) and UFT (400 mg orally/day for 2 years maximum). Group B (29 cases) was designed as the aforementioned minus BCG instillation. Cumulative non-recurrence rates in group A and group B were 80.1% and 72.1% at the time of three years, which revealed no significant difference between the two groups (p = 0.265, generalized Wilcoxon test). The high recurrent incidence of superficial bladder cancer is primarily due to the multifocal nature of the cancer or implantation of tumor cells at the time of the subsequent transurethral resection. The procedure was performed safely with no severe side effects. Our method might be useful to reduce the recurrences of superficial bladder cancer after transurethral resection of bladder (TUR).
The effects of acetylcholine (ACh) and adrenaline on fast axoplasmic transport of cultured superior cervical ganglion cells were analyzed with a computer-assisted video-enhanced differential interference contrast microscopic system. ACh suppressed the transport reversibly in both anterograde and retrograde directions, and adrenaline increased the transport reversibly. These effects are related to the amount of c-AMP. This amount of c-AMP in connection with neurotransmitters controls the axoplasmic transport, which in turn is related to the activity of the neuron.
We examined the myosin-coated surface of polystyrene beads, which slide on actin filaments in the presence of ATP with characteristics essentially similar to those of contracting muscle, using a high-resolution scanning electron microscope (JSM-890, JEOL). The bead surface was mostly covered with myosin filaments (diameter, 15-45 nm) with helically arranged myosin heads. Considering the amount of force generated by the myosin heads on the bead (approximately 10 pN), this result indicates that the bead movement may be caused by about 10 myosin heads within a short myosin filament segment, but not by randomly oriented myosin heads.
Organelle transport in cultured smooth muscle cell from the rabbit basilar artery was observed. The organelles transported in the cells were moving in both centrifugal and centripetal directions. The instantaneous velocities of organelles were 0.84 +/- 0.36 micron/s in the centrifugal direction and 0.86 +/- 0.48 micron/s in the centripetal direction. The transported organelles consisted mainly of lysosomes (67.5%) and mitochondria (29.0%).
We surveyed the attitudes of general surgical patients to the management of their postoperative pain relief. Elective surgical patients (n = 232) were asked postoperatively about their experienced pain which was expressed according to verbal pain scale, the duration of experienced pain, satisfaction with pain relief and medication, and expectations of pain on the 5th to 7th postoperative day. Thirteen percent of the patients had no pain, 47% of whom had no rest pain but pain on moving or coughing, 32% of whom had rest and moving pain, and 0.4% of whom experienced horrible and excruciating pain. Duration of postoperative pain was 2.5 +/- 1.9 days, and 76% of the patients experienced pain only for 3 postoperative days. Results of the interviews indicated that 80% of these patients were satisfied with their postoperative pain relief. Although 80% expressed satisfaction, 39% of whom did have rest pain. In the patients with continuous epidural infusion of buprenorphine and 0.25% bupivacaine, incidence of complained rest pain was significantly low compared with those with intermittent i.v. and/or im injection of analgesics on demands of patients. Lag between patient's demand and nurse's response concerning medication correlated significantly to the satisfaction. There was no relation between satisfaction and age, the nature of operation or sex. Fifty-two percent of the patients reported that degree of experienced pain had been less than expected preoperatively. In conclusion, 80% of the patients were satisfied, but our postoperative pain therapy was still insufficient because 39% of them had rest pain.(ABSTRACT TRUNCATED AT 250 WORDS)
Protein tyrosine phosphorylation was examined after T cells were exposed to oxidative stress in vitro to investigate the possible involvement of redox regulation in T-cell signaling. Oxidative reagents such as hydrogen peroxide (H2O2) and diamide, which oxidize the free sulfhydryl groups in the cells, markedly induced tyrosine phosphorylation of multiple cellular proteins, especially a 55-kDa protein, of cultured peripheral blood T lymphocytes (PBL blasts). The 55-kDa molecule phosphorylated by diamide turned out to be a src family protein tyrosine kinase, p56lck. The immune complex kinase assay showed that the kinase activity of p56lck of diamide-treated PBL blasts was enhanced. The tryptic peptide mapping of p56lck demonstrated that diamide induced the phosphorylation both at Tyr-394 (autophosphorylation site) and at Tyr-505 (negative regulatory site). Taken together, the tyrosine phosphorylation and presumably kinase activity of p56lck were swiftly enhanced by oxidative stress, indicating that T cells have a redox-sensitive signaling mechanism, which is partly mediated by the lymphocyte-specific protein tyrosine kinase p56lck.