Search PubMed⌕ Search

Biomedical subjects

T Handa

Publications and source records attributed to T Handa.

At least 73 records · Page 4Linked to original sources

Isolated intramedullary spinal artery aneurysm presenting with quadriplegia. Case report.

The case is presented of an isolated intramedullary posterior spinal artery aneurysm at the C-2 level in a 3-year-old girl. Quadriplegia related to probable intramedullary hemorrhage was the presenting symptom. Magnetic resonance imaging revealed findings consistent with an intramedullary vascular lesion, and vertebral angiography confirmed this to be an aneurysm of the posterior spinal artery. No associated vascular abnormalities were noted, and the aneurysm was successfully resected. Previous reports of isolated spinal aneurysms are reviewed.

Aneurysm↗

[A case report of adenoid cystic carcinoma of the nasal septum].

A 50-year-old woman with adenoid cystic carcinoma of the nasal septum is presented. Her chief complaint was recurrent epistaxis. Surgery was originally performed to remove a nasal polyp, but during resection, the surgeon discovered that the mass had arisen from the nasal septum, so only a biopsy was done. The pathological report was adenoid cystic carcinoma, so she was referred and admitted to our hospital. A flat 1.5 x 1.5 cm tumor was recognized on the left side of the nasal septum. Nasal septectomy was performed. The tumor was dissected with nasal septal cartilage, and the defect was covered with a free skin flap from the thigh. The incidence of malignant tumors from the nasal septum is very low, composing from 2.7% to 8.4% of nasal and paranasal malignant tumors. Therefore the incidence of adenoid cystic carcinoma in particular is very low.

Carcinoma, Adenoid Cystic↗

[Diagnosis on Mycoplasma pneumoniae infections by DNA-probe assay in comparison with serological tests].

To evaluate the usefulness of DNA diagnosis as a diagnostic approach to Mycoplasma pneumoniae infections, we compared the DNA-probe assay with serological tests in 32 patients who were clinically suspected of having Mycoplasma pneumonia. The DNA-probe assay was carried out using the Gen-probe kit. Serological tests included complement fixation and passive hemagglutination tests. At first visit 10 patients were positive for the DNA-probe assay, while only 2 of them were positive for serological tests. The other 3 patients became positive for serological tests during the clinical course. In accordance with clinical improvement, these patients became negative for the DNA-probe assay. Three patients were negative for DNA-probe assay while they were positive for the serological tests. However, these patients had already received antibiotics; therefore, their conditions were considered to have been improved at the time of the study. The other 19 patients were negative for both the DNA-probe assay and serological tests. These patients might have suffered from respiratory tract infections of pathogenic organisms other than M. pneumoniae or the number of M. pneumoniae might have been too small to be detected by the DNA-probe assay. The results of the present work demonstrate that the DNA-probe assay was valuable in the diagnosis of mycoplasmal infections at the early stage, which indicates that DNA diagnosis provides useful information to determine the most appropriate therapeutic regimen.

Child↗

Effect of recombinant human granulocyte colony-stimulating factor (rh G-CSF) on murine resistance against Listeria monocytogenes.

Recombinant human granulocyte colony-stimulating factor (rh G-CSF) enhanced resistance of mice against Listeria monocytogenes (LM) as determined by survival and bacterial growth. Mice pretreated with rh G-CSF twice daily for 5 days survived better than untreated animals to the challenge with LM. Number of bacteria in peritoneal cavity (PC) and spleen was lower in treated mice than that in the control group. Rh G-CSF increased mainly polymorphonuclear cells (PMN) in blood and spleen. After LM inoculation, a larger number of PMN and monocyte-macrophages accumulated in PC and spleen of tested mice. In addition, PMN primed in vivo with rh G-CSF released more superoxide anions when stimulated with phorbol myristate acetate. The inhibition of bacterial growth in PC and spleen could be ascribed to the accumulation of phagocytic cells at the infection sites and the increased oxidative metabolism. The results provided further evidence of the important contribution of G-CSF and neutrophils, as target cells, to the host defence against the intracellular bacteria.

Animals↗

Functional electrical stimulation (FES) systems for restoration of motor function of paralyzed muscles--versatile systems and a portable system.

Multichannel functional electrical stimulation (FES) systems were developed to restore the motor functions of the paralyzed muscles, i.e. two kinds of versatile systems for laboratory use and a practical portable system were developed. The first microcomputer-based FES system was composed of an 8 bit microcomputer (PC-8801mkII) with a voice recognition board and 30 stimulation outputs, in which the voice commands were used for selecting a motion pattern, and for executing (start), (hold), (restart) and (stop) commands. In combination with the voice commands, a proportional control command detected from a head angle sensor was used for volitional control of motion. The second microcomputer-based FES system was composed of a 16 bit microcomputer (PC-9801 UV or compatible) with flexible control capabilities (e.g. respiratory sensors) for volitional control and with 64 stimulation outputs. An originally designed practical portable FES system was 89 x 145 x 31 mm in dimension and 380 g in weight. This paper describes the system configurations, the control methods of these FES systems and three examples of the clinical applications of the FES systems.

Electric Stimulation Therapy↗

Difference in the functional maturation of T cells against Listeria monocytogenes in lymph nodes and spleen.

After subcutaneous immunization of mice with viable Listeria monocytogenes (LM), we evaluated the function of T cells induced in draining lymph nodes (LN) and spleen as determined by the local transfer of delayed-type hypersensitivity (DTH), acquired cellular resistance (ACR) and in vitro lymphokine production. LN cells could transfer specifically DTH but not ACR. In contrast, spleen cells from the same donor mice evoked the DTH response as well as bacterial clearance at the reaction site. Comparison of bacterial counts in spleen and in LN upon subcutaneous inoculation of mice with LM suggested that the lack of bacterial proliferation in LN underlay the failure to induce protective T cells in this lymphoid tissue. Spleen and LN T cells expressed CD4 and CD8 surface antigens equally and DTH response was solely dependent on CD4+ cells. Another major difference between LN and spleen cells was the profile of lymphokines produced in vitro. Upon the in vitro restimulation with killed Listeria, immune spleen cells produced macrophage chemotactic factor (MCF), interleukin-2 (IL-2) and interferon-gamma (IFN-gamma). In contrast, LN cells could produce all of the measured lymphokines but not IFN-gamma. The results provided strong evidence for the dissociation of DTH and ACR. Listerial growth appeared to be the requirement for full maturation of anti-listerial immunity that may coincide with the generation of IFN-gamma-producing T cells.

Animals↗

[Evaluation of DNA-probe assay for the clinical diagnosis of Mycoplasma pneumoniae infections].

DNA probe-assay using the Gen-Probe kit was carried out to detect Mycoplasma pneumoniae infections. Fifteen children visited Ota General Hospital complaining of dry cough and high grade fever. Throat swabs of the patients were examined to detect M. pneumoniae ribosomal RNA by Gen-Prove kit. Five out of 15 patients were positive for DNA probe assay of M. pneumoniae. Clinical and laboratory data including serological examinations were compatible with M. pneumoniae infection in these cases. Following the improvement of clinical symptoms and signs by receiving erythromycin or minocycline, the positivity for DNA probe assay turned to negative. Among the ten patients, who were negative for DNA probe assay, 2 cases were suspected of M. pneumoniae infection on the basis of clinical and laboratory findings. One patient had already taken antibiotics. Therefore, in these two patients, there was a possibility that the bacterial numbers were too small to be detected by DNA-probe assay. The data described above support that DNA-probe assay is useful for the diagnosis of M. pneumoniae infections in the early stage. DNA-probe assay is also valuable to follow up the clinical course of the patients.

Child↗

[Effects of heavy metal ions in endocochlear DC potential and cochlear microphonics in the guinea pig--the influence of calcium on the cochlea].

Endocochlear DC potential (EP) and cochlear microphonics (CM) in the guinea pig under the influence of the divalent heavy metal cations of manganese, nickel, cobalt and cadmium, and the trivalent cation of lanthanum were investigated. The area from the scala tympani to the scala vestibuli was perfused with control and test solutions. CM decreased gradually to 50-80%, but EP showed no change after perfusion with a solution containing 1 mM of metal ions. At a concentration of 10 mM, EP decreased from 80 mV to 10-20 mV and CM decreased to 15-55%. At 100 mM, EP increased by about 10 mV at the beginning of perfusion, remained steady for 1 min, and then rapidly decreased to 0-10 mV. Meanwhile, CM continued to decrease, finally sustaining a 10-56% reduction. The decrease in EP and CM were irreversible, and perfusion of the area with the standard solution for 20 min had no effect. The osmolarity of the artificial perilymph containing 100 mM of metal ions was twice as high as that of the normal physiological solution. The effects of osmolarity, however, were excluded because perfusion with an artificial perilymphatic solution made hypertonic by either NaCl or sucrose changed neither EP nor CM. The application of 100 mM of metal ions topically to the round window membrane caused no change in EP. The alkali metal ions are known to inhibit inward Ca2+ current. Therefore, the present results suggest that Ca2+ ions play a role in maintaining EP generation in the stria vascularis and CM generation in the organ of Corti.

Animals↗

A dissociated induction of MCF-producing and MAF-producing T cells specific for Listeria monocytogenes in the in vitro primary culture system.

Using an in vitro primary culture system which we had previously established, the induction phase of Listeria monocytogenes-specific effector cells was analysed with respect to their abilities to produce effector lymphokines, macrophage chemotactic factor (MCF) and macrophage-activating factor (MAF). Listeria-specific effector cells generated after in vitro culture of normal spleen cells with viable L. monocytogenes for 5 days conveyed L3T4+, Lyt-2-, Thy-1+ surface antigens and produced MCF and MAF in response to the secondary stimulation with heat-killed L. monocytogenes. The cells required for the induction of Listeria-specific effector cells, which produce effector lymphokines, MCF and MAF, were L3T4+, Lyt-2-, Thy-1+ cells. The kinetic analysis revealed that the ability of these effector cells to produce MCF was generated earlier than that to produce MAF. Furthermore, using passive transfer of cells, the effector cells producing only MCF, which were generated early in culture, conferred delayed-type hypersensitivity (DTH) alone, but MCF- and MAF-producing effector cells generated late in culture conferred sufficient levels of DTH and acquired cellular resistance (ACR). These results indicate a dissociated production of MCF and MAF by L. monocytogenes-specific T cells generated in the primary in vitro culture system.

Animals↗

Phospholipid monolayers at the triolein-saline interface: production of microemulsion particles and conversion of monolayers to bilayers.

Interfacial tensions of phospholipid monolayer at the triolein (TO)-saline interface were measured. The adsorption isotherms and the interfacial pressure-molecular area curves were evaluated on the basis of the measurements. Phosphatidylcholine (PC) forms a highly condensed monolayer, with a large lateral attractive interaction; phosphatidylethanolamine (PE) and phosphatidylserine (PS) form expanded monolayers with smaller lateral interaction energies. At the lowest interfacial tension (the highest interfacial pressure), the mole fractions of PC, PE, and PS in the monolayers are estimated as 0.95, 0.73, and 0.88, respectively. Therefore, PC forms the most stable monolayer at the interface. These results are consistent with the finding that the stable TO particles in aqueous solution were produced by using PC as an emulsifier, and PE and PS did not stabilize the particles. The phase diagram of TO and PC mixtures in saline obtained from theoretical considerations predicts the equilibrium conversion of the monolayers on TO particles to bilayers. This process may be closely related to the transformations of very low density lipoproteins and chylomicrons to high-density lipoproteins in plasma. The particle sizes of the emulsion are calculated theoretically as a function of PC mole fraction in the TO-PC mixture and compared with the experimental values obtained from quasi-elastic light scattering (QLS) measurements.

Adsorption↗

Interactions of lecithin and pig apolipoproteins of high density lipoproteins at the surface monolayer of reconstituted very small particles.

Cosonication of egg yolk lecithin and triolein with apolipoproteins isolated from pig high density lipoprotein (apoHDL) gave us reconstituted high density lipoprotein particles (r-HDLs) of 9 nm in average diameter. They were smaller than microemulsion particles (MEs) composed of the lipids (35 nm). The protein/egg yolk lecithin ratio in the fractionated r-HDLs was higher in the smaller particles. Binding of a hydrophobic probe, 2-p-toluidinylnaphthalene-6-sulfonate (TNS), to MEs, r-HDLs and apoHDL were evaluated on the basis of Halfman and Nishida's method. The reconstitution of apoHDL into MEs led to a 68% reduction in the binding of TNS and a small increase in the alpha-helix content as compared with free apoHDL. The binding experiments also showed the condensation of lecithin molecules at the r-HDL surface. The amphipathic helixes of apoHDL are located in the surface monolayer of egg yolk lecithin surrounding the triolein core. The intercalation of the hydrophobic residues of apoHDL between egg yolk lecithin molecules brings about a pronounced curvature of the surface and a decrease in the particle diameter.

Animals↗

Determinants of maximum walking speed in hemiparetic stroke patients.

The time necessary to walk 10 m with the fastest speed, the sway path of the center of feet pressure in station, and the isokinetic strength for knee extension of each side were examined in 29 hemiparetic stroke patients. The maximum walking speed of the patients was related to the sway path and the isokinetic muscle strength of affected side. The patients could be divided into two groups based on their sway path. The determinants of the maximum walking speed in the unstable group were the sway path and the isokinetic muscle strength of the both sides, whereas that in the stable group was only the isokinetic muscle strength of affected side.

Adult↗

[An adult case of malignant choroid plexus papilloma in the lateral ventricle and the cerebellopontine angle revealed simultaneously].

An adult case of malignant choroid plexus papilloma is very rare. This report is an adult case of malignant choroid plexus papilloma revealed in the lateral ventricle and in the cerebellopontine (CP) angle simultaneously. A 37-year-old man was admitted to the hospital complaining of headache, nausea, and a floating sensation on August 29, 1984. Neurological examination on admission revealed bilateral papilledema, left dysmetria and horizontal nystagmus. CT scan revealed a slightly high density round mass in the right lateral ventricle and a cystic mass with mural nodule in the left CP angle. The intraventricular mass and mural nodule were enhanced moderately and homogeneously. The initial surgery was for removal of the CP angle tumor, and 8 days later removal of the lateral ventricle tumor was carried out. The histology of these tumors was the same and revealed malignant choroid plexus papilloma. Postoperative radiation therapy was carried out 70Gy to the brain (whole brain; 50Gy, focal; 20Gy) and 30Gy to the whole spine. About 2 years later paraparesis, lower cranial nerve palsy, and disturbance of consciousness had progressed gradually. He died of the severe recurrence of the tumor in the brain stem, and multiple dissemination in the spinal cord on September 6, 1987. There was no recurrence of tumor in the right lateral ventricle. This is a very rare case of malignant choroid plexus papilloma which was revealed in both the supra- and infratentorial regions simultaneously. They may have developed independently or they may have arisen through subarachnoid seeding. Radical removal of the tumor is important to prevent recurrence of malignant choroid plexus papilloma.

Adult↗

Hypelcin A, an alpha-aminoisobutyric acid containing antibiotic peptide, induced permeability change of phosphatidylcholine bilayers.

Interactions of hypelcin A, an alpha-aminoisobutyric acid containing antibiotic peptide, with phosphatidylcholine vesicles were investigated to obtain information on its bioactive mechanism. The peptide induced the leakage of a fluorescent dye, calcein, entrapped in sonicated vesicles. The leakage rate depended on both the peptide and the lipid concentrations. Analysis of this dependency indicated that the leakage was due to the monomeric peptide and that the membrane-perturbing activity of the monomer was higher for solid distearoylphosphatidylcholine vesicles than for fluid egg yolk phosphatidylcholine vesicles. Hypelcin A also affected the gel to liquid-crystalline phase transition of dipalmitoylphosphatidylcholine multilamellar vesicles. The transition was broadened with a reduced transition enthalpy, suggesting the peptide strongly binds the surrounding lipids to perturb the bilayer lipid packing. A circular dichroism study revealed that the helical content of hypelcin A increases upon membrane binding. We concluded that the monomeric peptide with an increased helical content, complexed with the lipids, perturbs the lipid organization and induces the increased permeability.

Alamethicin↗

Magainin 1-induced leakage of entrapped calcein out of negatively-charged lipid vesicles.

Effects of magainin 1, a novel antimicrobial peptide, on the permeability of lipid vesicles were investigated by using calcein as a trapped fluorescent marker. Magainin 1 induces the leakage of calcein specifically out of negatively-charged vesicles. The peptide binds to bovine brain phosphatidylserine sonicated vesicles according to the Langmuir isotherm with a binding constant of 3.8.10(5) M-1 and a binding-site number of 0.10 per lipid molecule. The leakage seems to occur at a critical binding number of approx. 0.03 per lipid molecule. A circular dichroism study revealed that magainin 1 conforms mainly to an unordered structure both in an aqueous solution and in the presence of egg yolk phosphatidylcholine vesicles, whereas to an amphiphilic helix with the phosphatidylserine vesicles. In conclusion, magainin 1 interacts with acidic lipids through electrostatic interactions followed by hydrophobic interactions to form an amphiphilic helix, inducing the leakage.

Animals↗

Preparation of controlled-release microspheres of ibuprofen with acrylic polymers by a novel quasi-emulsion solvent diffusion method.

A novel quasi-emulsion solvent diffusion method to prepare the controlled-release microspheres of ibuprofen with acrylic polymers has been developed. An ethanol solution of ibuprofen and acrylic resin was poured into aqueous medium with stirring. The finely dispersed ethanolic droplet-like coacervates formed in aqueous medium were gradually solidified and transformed into microspheres during agitation. The size of microspheres was determined by the concentrations of drug and polymer and the agitation speed of the system. The flowability, the packability, and the compressibility of the resultant microspheres were much improved compared with the raw crystals of the drug. The drug release rate from the microspheres could be controlled by the type and the concentration of polymer formulated. A unique principle of the present method and the resultant microspheres, having a matrix- or sponge-like texture, can provide characteristic advantages compared with a conventional reservoir-type device drug, like a microcapsule.

Acrylates↗

A low degree of requirement for Ia-positive macrophages and IL 2 in the induction phase of Listeria monocytogenes-specific T cells in vitro.

We have analyzed the priming process of Listeria-specific T cells using an in vitro primary culture system. Listeria-specific T cells mediating delayed footpad reaction (DFR) and acquired cellular resistance (ACR) upon passive local transfer into naive recipients were generated from non-immune mouse spleen cells when stimulated with viable Listeria monocytogenes primarily in vitro. The effectors were detected on the third day of culture, and culturing for 5 days was sufficient for the generation of effectors mediating the peak level of DFR and ACR. The requirement of T cell subsets, Ia antigen and interleukin 2 (IL 2) for inducing effectors was studied. Presence of macrophages (M phi) and their contact to T cells were required for priming of Listeria-specific T cells in vitro. The presence of Ia antigens on macrophages was absolutely required for priming, but this requirement was lower than that in secondary immune response of Listeria-specific T cells. Effectors could not be generated when L3T4+ cells were depleted, but effectors capable of conferring a full level of DFR and ACR were induced even after the depletion of Lyt2+ cells. Contribution of IL 2 to the generation of effectors during early phase of priming was not observed. IL 2 was not produced in the supernatant of the in vitro primary culture. Precursor cells of the effectors did not respond to exogenously added recombinant IL 2 (rIL 2). Some mechanisms operating in the induction phase of Listeria-specific T cells were clarified in this study.

Animals↗

Role of antibodies against outer-membrane proteins in murine resistance to infection with encapsulated Klebsiella pneumoniae.

In the assessment of immunity to the encapsulated virulent strain of Klebsiella pneumoniae and its avirulent mutant defective for capsular polysaccharide (CPS), killed bacterial vaccine of both strains could protect mice equally against challenge with 100 x LD50 of encapsulated wild strain. Antisera to each strain conferred the same level of protection on naive mice upon transfer; the protective anti-mutant serum was highly capable of opsonizing the encapsulated bacteria. In addition to the common antigenic components shared by both strains, the wild strain had antigen(s) unrelated to the mutant since the protective capacity of the anti-wild serum was not affected by preabsorption with the mutant strain; the protection conferred by the anti-mutant serum was mediated by antibodies against non-capsular antigens since the antiserum did not contain antibodies against purified CPS detectable by ELISA. As possible candidates among the non-capsular antigens, outer-membrane proteins (OMPs) extracted from the mutant strain were examined for their immunogenicity. Immunoblotting of the protein-containing fraction and ELISA using LPS-free OMP suggested that a number of proteins were involved in the immune response evoked by K. pneumoniae. Furthermore, mice immunized with OMP or anti-OMP serum could overcome a lethal challenge with the wild strain. These results indicated that OMPs of K. pneumoniae are implicated as the protective antigens and may pave the way for the development of non-capsular, proteinaceous vaccines.

Animals↗