Left atrial appendage function in patients with single-chamber ventricular pacing.
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Aged↗
Biomedical subjects
K Sano
Publications and source records attributed to K Sano.
A novel type of cell death of lymphocytes induced by a monoclonal antibody without participation of complement.
A monoclonal antibody, RE2, raised by immunizing a rat with cell lysate of a mouse T cell clone, was found to directly kill interleukin 2-dependent T cell clones without participation of serum complement. Fab fragments of RE2 had no cytolytic activity, while the cross-linking of Fab fragments with anti-rat immunoglobulin reconstituted the cytotoxicity. The cytotoxicity was temperature dependent: the antibody could kill target cells at 37 degrees C but not at 0 degrees C. Sodium azide, ethylenediaminetetraacetic acid, and forskolin did not affect the cytolytic activity of RE2, while the treatment of target cells with cytochalasin B and D completely blocked the activity. This suggested that the cell death involves a cytoskeleton-dependent active process. Giant holes on the cell membrane were formed within 5 minutes after the treatment with RE2, as observed by scanning electron microscopy. There was no indication of DNA fragmentation nor swelling of mitochondria during the cytolysis, suggesting that the cell death is neither apoptosis nor typical necrosis. The antibody also killed T cell lymphomas and T and B cell hybridomas only when these cells were preactivated with concanavalin A, lipopolysaccharide, or phorbol myristate acetate. Preactivated peripheral T and B cells were sensitive to the cytotoxicity of RE2, while resting T and B cells were insensitive. These results provide evidence for a novel pathway of cell death of activated lymphocytes by membrane excitation.
Animals↗
Phase diagrams of the electronic state of the one-dimensional d-p model.
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Journal Article↗
Biodegradable sponges for hepatocyte transplantation.
Liver cell transplantation may provide a means to replace lost or deficient liver tissue, but devices capable of delivering hepatocytes to a desirable anatomic location and guiding the development of a new tissue from these cells and the host tissue are needed. We have investigated whether sponges fabricated from poly-L-lactic acid (PLA) infiltrated with polyvinyl alcohol (PVA) would meet these requirements. Highly porous sponges (porosity = 90-95%) were fabricated from PLA using a particulate leaching technique. To enable even and efficient cell seeding, the devices were infiltrated with the hydrophilic polymer polyvinyl alcohol (PVA). This reduced their contact angle with water from 79 to 23 degrees, but did not inhibit the ability of hepatocytes to adhere to the polymer. Porous sponges of PLA infiltrated with PVA readily absorbed aqueous solutions into 98% of their pore volume, and could be evenly seeded with high densities (5 x 10(7) cells/mL) of hepatocytes. Hepatocyte-seeded devices were implanted into the mesentery of laboratory rats, and 6 +/- 2 x 10(5) of the hepatocytes engrafted per sponge. Fibrovascular tissue invaded through the devices' pores, leading to a composite tissue consisting of hepatocytes, blood vessels and fibrous tissue, and the polymer sponge.
Animals↗
The post-transcriptional regulator Rex of the human T-cell leukemia virus type I is present as nucleolar speckles in infected cells.
The rex-encoded protein (Rex) of human T-cell leukemia virus type I (HTLV-I) is responsible for the cytoplasmic accumulation of incompletely spliced mRNAs that encode the virion structural proteins. Rex is known to be located predominantly in the cell nucleoli in transient transfections or in the isolated nuclei of HTLV-I-infected cells. However, precise location of Rex under physiological conditions has not been determined unequivocally. Here we report that Rex is primarily located as intranucleolar speckles in HTLV-I-infected cells, except for a few nucleoplasmic speckles. This is in contrast to the more diffuse nucleolar distribution of the rev-encoded protein (Rev) of human immunodeficiency virus type 1 (HIV-1), the functional homologue to Rex, in HIV-1-infected cells. Accumulation of Rev is associated with disruption of nucleolar structure and cell death, whereas Rex does not have these effects. The difference in distribution of Rex and Rev within the nucleoli may reflect the difference of toxicity toward the host cells. Involvement of the nucleolus in processing of certain mRNAs is also discussed.
Animals↗
Improved detection of medically important fungi by immunoperoxidase staining with polyclonal antibodies.
This study was performed to identify pathological fungi of eight species [Aspergillus fumigatus, Candida albicans, Torulopsis (Candida) glabrata, Cryptococcus neoformans, Fusarium anthophilum, Rhizopus oryzae, Sporothrix schenckii and Trichosporon beigelii] in formalin-fixed, paraffin-embedded tissue sections by indirect immunoperoxidase staining. Mature albino rabbits were immunized with formalin-killed organisms. Antibodies were prepared by precipitation. Immunoperoxidase staining was applied to the paraffin-embedded tissue sections of experimentally infected mice and human autopsy and surgical specimens. Although the cell walls of each fungus stained clearly, many cross-reactivities appeared. However, it was possible to obtain specificity for the eight species by absorption and dilution of the antisera.
Animals↗
Japanese mentality and behaviour--based on the indigenous Japanese culture.
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Buddhism↗
Parasellar Aspergillus granuloma extending from the sphenoid sinus: report of two cases.
BACKGROUND: Sphenoid sinus aspergillosis is a rare disease known to show an aggressive course with high mortality. Early diagnosis, though difficult, is required to prevent lethal fungal meningoencephalitis. CASE REPORT: We describe two cases of parasellar Aspergillus granuloma extending from the sphenoid sinus clinically indistinguishable from intracranial neoplasms. In the first patient, the fungus colony was visualized by computed tomography (CT) and magnetic resonance imaging (MRI) as a calcified concretion and total removal was curative. In the second patient, partial removal and subsequent antifungal therapy had minimal effect. CONCLUSIONS: The prognosis of the patients with this disease depends on prompt surgical treatment before intradural invasion occurs, and CT and MRI are useful diagnostic maneuvers for detecting calcified Aspergillus colonies.
Aged↗
Comparable sensitivities for detection of HIV-1 reverse transcriptase (RT) and other polymerases by RT assays requiring no radioisotopic materials.
An improved non-radioisotopic (Non-RI) reverse transcriptase (RT) assay with a template-primer-immobilized microtiter plate is described, which has greater sensitivity than the former Non-RI RT assay previously described. Non-RI and commercially available non-radioactive (Non-RA) RT assays were compared for their ability to detect various polymerases. Two RTs from Rous-associated virus 2 (RAV-2) and avian myeloblastosis virus (AMV), one polymerase from Escherichia coli (Pol-I) and one recombinant RT of human immunodeficiency virus type 1 (HIV-1) were assessed. Two HIV-1 samples in a culture supernatant and pelleted virion suspended in Triton X-100 solution were measured. The Non-RI RT assay was one hundred times more sensitive by RAV-2 and Pol-I polymerases, and one thousand times more sensitive by the Non-RA assay than by the AMV RT. The Non-RI RT assay was 10, 16 and 64 times more sensitive than the Non-RA assay for measuring recombinant HIV-1 RT, pelleted virus and virus suspended in culture medium, respectively. To explain the discrepancy, it is shown that free biotin, such as in culture medium, disturbs the assay system of the Non-RA RT assay, but not the Non-RI assay. The present assay can be used to clarify the inhibitory mechanism of an anti-HIV-1 substance.
Animals↗
Effects of intracoronary infusion of an inotropic agent, E-1020 (loprinone hydrochloride), on cardiac function: evaluation of left ventricular contractile performance using the end-systolic pressure-volume relationship.
The phosphodiesterase (PDE) III inhibitor, E-1020 (loprinone hydrochloride), has positive inotropic and vasodilating effects. This study evaluated the positive inotropic effect of intracoronary E-1020 in eight patients with coronary artery disease and hypertensive heart disease. A direct intracoronary infusion of the PDE III inhibitor minimizes its vasodilating effect. After baseline hemodynamic measurements and coronary arteriography, a micromanometer-tipped 8F conductance catheter was introduced into the left ventricle to determine the hemodynamic effects of E-1020. Saline and vehicle were infused into the left main coronary artery at a rate of 2 ml/min. The dose of intracoronary E-1020 increased from 2.5 to 5.0 and 7.5 micrograms/min. The inotropic effect of E-1020 was defined as the change in the slope of the end-systolic pressure-volume relationship (Emax), which was independent of afterload and preload. Emax significantly increased at infusion rates of 7.5 micrograms/min from control. Peak +dP/dt increased at an infusion rate of 5.0 micrograms/min or higher, while left-ventricular end-diastolic pressure (LVEDP) decreased significantly at a rate of 5.0 and 7.5 micrograms/min. Intracoronary infusion of E-1020 at a rate of 2.5 micrograms/min produced a plasma concentration of 20 ng/ml, which was identical to the minimum effective plasma concentration seen in previous study by intra venous infusion. However, at a plasma concentration of 20 ng/ml, E-1020 has more vasodilating effects than inotropic effects. Clinically, E-1020 appears to have a positive inotropic effect that depends on the extent of myocardial perfusion.
Aged↗
Effect of aging on the rat condylar fracture model evaluated by bromodeoxyuridine immunohistochemistry.
PURPOSE: The effect of aging on the recovery of cellular proliferative ability in the experimentally fractured rat condyle was studied by bromodeoxyuridine (BrdU) immunohistochemistry. MATERIALS AND METHODS: The experimental animals (male Sprague-Dawley rats; n = 33, unilateral condylar fracture and sham operation) were divided into three age groups: 3, 6, and 36-weeks old. The cell proliferation was evaluated by the BrdU labeling index (LI) in the intermediate cell layer of the condyle at 1, 2, 4, 6, and 8 weeks after the fracture. RESULTS: The cell kinetics of both condyles was affected by the temporomandibular joint dysfunction due to the unilateral condylar fracture. In all age groups, the fracture healed within 4 weeks. The LI of the nonfractured as well as fractured condyles decreased strikingly up to 2 weeks, and then only slightly increased at 4 weeks after the fracture. The LIs of the fractured condyles were lower than those of the control throughout the experiment regardless of age. Eight weeks after the fracture the percentage of recovery of the LI in the fractured condyle (LIs of fractured condyle in the fracture group/LIs of right condyle in the sham group) was 45.1% in 3-week-old-animals, 21.2% in 6-week-old-animals, and 16.1% in 36-week-old-animals. CONCLUSION: This study shows that the recovery of cell proliferation in the fractured condyle depends on age.
Aging↗
Appraisal of intraoperative ultrasonography during laparoscopic cholecystectomy.
BACKGROUND: The usefulness of intraoperative ultrasonography during laparoscopic cholecystectomy (LC) has yet to be evaluated fully. METHODS: In 50 patients who underwent LC, the intraoperative ultrasonography findings were compared with those of preoperative ultrasonography, intraoperative cholangiography, and histology, and then its usefulness for examining anatomic relationships in the hepatoduodenal ligament, detecting bile duct stones, diagnosing gallbladder polyps and abnormally thickened walls, and determining the propriety of LC was appraised. RESULTS: The preoperative ultrasonography diagnoses were gallstones in 38 patients, polyps in 10, and cancer and adenomyomatosis in one each. In four patients endoscopic retrograde cholangiography showed bile duct stones. In all 50 patients intraoperative ultrasonography was useful for examining the anatomic relationships between the bile duct and vessels, such as the portal vein and hepatic artery, and showing the presence or absence of bile duct stones. On the basis of the intraoperative ultrasonography findings, gallstones were diagnosed in 38 patients, in five of whom bile duct stones were shown clearly, cholesterol polyps in eight, early-stage cancer or adenoma in two, and adenomyomatosis in two, and subsequently LC was performed. Histologic diagnoses of cholesterol polyps were made in eight of ten patients with polyps, and intramucosal cancer and an inflammatory polyp in one each. In one patient with a preoperative diagnosis of cancer the apparently elevated flat lesion was found to be partial thickening of the gallbladder wall, which was diagnosed as adenomyomatosis, and LC was chosen as the operative procedure. CONCLUSIONS: Intraoperative ultrasonography during LC is useful for detecting bile duct stones, diagnosing gallbladder polyps and abnormally thickened walls, and deciding whether LC is adequate for resection of the gallbladder.
Adult↗
Perceptual changes accompanying controlled blocking of cutaneous afferents are related to somatosensory evoked potentials.
We examined the effect of local anaesthesia of the skin on somatosensory evoked potentials (SEPs) and psychophysical magnitude estimates for a constant intensity air-puff stimulation (7 kg.cm-2) in 23 normal subjects. Before and after intradermal injection (0.1 ml of 1% xylocain) to the tip of the right index finger, magnitude estimations for the four modalities of skin sensation (touch, pressure, pain and vibration), and SEPs were successively examined at 4-10 min interval until complete sensory and SEP recovery. The time course of sensory recovery was similar for the first three modalities and vibration sense was little affected by local anaesthesia. Immediately after anaesthesia, SEPs either abolished or decreased in amplitude. Thereafter amplitudes increased and peak latencies decreased with the elapsed time. Comparison of the regression lines for the amplitude of P45-N60 component or the time-integrals of N20 and N35 components with that of psychophysical estimates revealed steeper slopes for psychophysical data: 0.4-0.7 for neural versus 1.4-1.7 for psychophysical data. These relations between SEPs and psychophysics following local anaesthesia bear a close parallel to those observed in our previous studies in a normal condition with increasing stimulus intensity. The SEP latencies for N20, P27 and N35 components were better correlated with recovery from anaesthesia. Direct comparisons of SEP measures with subjective magnitudes produced significant correlations for the three modalities of sensation in which again latencies are better correlated than amplitides or time-integrals.
Adolescent↗
So-called intracranial germ cell tumours: are they really of germ cell origin?
We have studied 139 cases of intracranial germ cell tumours up to the beginning of 1993, 63.3% of which showed monotypic histological patterns and 36.7% were shown to be mixed tumours. All these cases underwent surgery followed by radiation and/or chemotherapy. All cases of choriocarcinoma died within 2 years. Cases of yolk sac tumour (endodermal sinus tumour) and embryonal carcinoma also showed poor results. Mature teratoma had a 5-year survival rate (5 YSR) and 10-year survival rate (10 YSR) of 92.9% each. Immature teratoma and malignant teratoma showed a 5-YSR and 10-YSR of 75.0% each. Germinoma showed a 5-YSR of 94.7% and a 10-YSR of 91.2%. All these results may bring into question the validity of the germ cell theory, since germinoma, which should be the most undifferentiated according to the theory, was the most benign and choriocarcinoma and yolk sac tumour (endodermal sinus tumour) which should be the most differentiated, were the most malignant in the follow-up study. Therefore, germ cell tumours may not originate from one single type of cells (primordial germs cells), except for germinoma. The embryonic cells of various stages of embryogenesis may perhaps be misplaced in the bilaminar embryonic disc and become involved in the stream of lateral mesoderm at the time of the primitive streak formation and be carried to the future cranial area to be wrongly enfolded into the brain at the time of the neural tube formation. The following law may be propounded: Tumours composed of cells resembling the cells appearing in the earlier stages of embryogenesis (ontogenesis) are more malignant than those resembling the cells appearing in the later stages of embryogenesis (ontogenesis).
Brain↗
Intussusception of the appendix: a report of three cases with different clinical and pathologic features.
Three cases of intussusception of the appendix (IA) with distinctive pathologic changes were reported. All patients were women with different clinical presentations. Grossly, a complete intussusception was found in one case (case 1), while the others (cases 2 and 3) showed a partial intussusception. In case 1, almost the total segment of the appendix bearing the villous adenoma with focal malignant transformation became completely telescoped into the cecum. In case 2, no underlying appendiceal lesion was disclosed. In case 3, appendiceal endometriosis was found as the point of traction. Awareness of such a rare complication associated with various appendiceal lesions provides a clue for making an accurate diagnosis and selecting appropriate surgical management.
Abdominal Pain↗
Cloning and nucleotide sequence of the gene for acidocin 8912, a bacteriocin from Lactobacillus acidophilus TK8912.
Acidocin 8912 is a bacteriocin produced by Lactobacillus acidophilus TK8912. The acidocin 8912 structural gene, acdT, was cloned and determined. It was located on the 14-kb plasmid pL103 and encoded a 46 amino acid precursor including a 20 amino acid N-terminal extension. The precursor sequence of the acdT gene shows a conservation of the general structural characteristics of the bacteriocin precursors from some lactic acid bacteria.
Amino Acid Sequence↗
A micro-suspension-test for evaluation of disinfectants against human immunodeficiency virus.
We devised a micro-suspension-test to evaluate disinfectants against human immunodeficiency virus type-1 (HIV-1) and confirmed its reliability. Suspensions of persistently HIV-1-infected Molt-4 cells were used as targets of disinfectants and residual infectivity was measured by an infectivity assay: after cocultivation with uninfected Molt-4 cells reverse transcriptase activity (RTA) in the supernatant and giant cell formation (GCF) were monitored. Our new infectivity assay consists of a short-term assay, that is RTA and GCF monitoring on the second day of co-culture, and a long-term assay, that is RTA monitoring up to the 28th day of co-culture. The sensitivity of the short-term assay was 1 x 10(3) infected cells and that of the long-term assay 1 x 10(1) infected cells. All the chemical disinfectants examined in this study showed dose- and time-dependent inactivation of HIV-1. By 5-minute contact with ethanol, glutaraldehyde, formalin, sodium hypochlorite and povidone-iodine, HIV-1 was effectively inactivated at concentrations of 20, 0.01, 5, 0.05 and 0.1%, respectively. Since the micro-suspension-test is easy and sensitive, we recommend it as a method for evaluating disinfectants against HIV-1.
Cells, Cultured↗
Isolation and characterization of acidocin A and cloning of the bacteriocin gene from Lactobacillus acidophilus.
Acidocin A, a bacteriocin produced by Lactobacillus acidophilus TK9201, is active against closely related lactic acid bacteria and food-borne pathogens including Listeria monocytogenes. The bacteriocin was purified to homogeneity by ammonium sulfate precipitation and sequential ion-exchange and reversed-phase chromatographies. The molecular mass was determined by high-performance liquid chromatography gel filtration to be 6,500 Da. The sequence of the first 16 amino acids of the N terminus was determined, and oligonucleotide probes based on this sequence were constructed to detect the acidocin A structural gene acdA. The probes hybridized to the 4.5-kb EcoRI fragment of a 45-kb plasmid, pLA9201, present in L. acidophilus TK9201, and the hybridizing region was further localized to the 0.9-kb KpnI-XbaI fragment. Analysis of the nucleotide sequence of this fragment revealed that acidocin A was synthesized as an 81-amino-acid precursor including a 23-amino-acid N-terminal extension. An additional open reading frame (ORF2) encoding a 55-amino-acid polypeptide was found downstream of and in the same operon as acdA. Transformants containing this ORF2 became resistant to acidocin A, suggesting that ORF2 encodes an immunity function for acidocin A. The 7.2-kb SacI-XbaI fragment containing the upstream region of acdA of pLA9201 was necessary for acidocin A expression in the acidocin A-deficient mutant, L. acidophilus TK9201-1, and other Lactobacillus strains.
Amino Acid Sequence↗