Biomedical subjects

M Doi

Publications and source records attributed to M Doi.

At least 55 records · Page 3Linked to original sources

PubMed2001

Dynamic and static 99mTc-ECD SPECT imaging of subacute cerebral infarction: comparison with 133Xe SPECT.

UNLABELLED: 99mTc-ethylcysteinate dimer (99mTc-ECD) SPECT imaging reportedly fails to show reflow hyperemia in patients with subacute stroke. This study attempts to determine the clinical usefulness of dynamic 99mTc-ECD SPECT in evaluating regional blood flow in subacute cerebral infarction and the kinetic behavior of 99mTc-ECD in infarct areas. METHODS: 133Xe and consecutive dynamic and static 99mTc-ECD SPECT studies were performed on 24 patients with cortical infarction in the middle cerebral artery territory 13-15 d after the onset of a stroke. Image contrast between infarct and contralateral control areas on 99mTc-ECD tomograms (ECD uptake ratio) was compared with that on cerebral blood flow (CBF) images obtained using 133Xe inhalation (CBF ratio). RESULTS: In all cases, ECD uptake ratios from static images were lower than CBF ratios. This tendency was obvious when CBF in the infarct area increased above the normal control value, and no significant correlation was found between ECD uptake ratios from static images and CBF ratios. Only in the infarct areas with CBF below the normal control value, however, was a significant correlation between the two maintained (r = 0.795; P = 0.0011). A very strong correlation was found between CBF ratios and ECD uptake ratios on both the first dynamic scan (36 s after injection) (r = 0.991; P < 0.0001) and the second dynamic scan (72 s after injection) (r = 0.945; P < 0.0001). The correlation coefficient decreased in a time-dependent manner, with no significant correlation observed after the fourth dynamic scan (144 s after injection). On the other hand, significant correlations were observed on all dynamic scans only in the infarct areas with CBF below the control value. CONCLUSION: Super-early images of dynamic 99mTc-ECD SPECT provide a close imaging contrast with CBF and reveal reflow hyperemia in areas with irreversible changes produced by subacute stroke, which static 99mTc-ECD SPECT images fail to show. Decreased retention of the tracer in the infarct areas with hyperperfusion causes an underestimation of CBF on static 99mTc-ECD SPECT images. Given these results, we believe that dynamic 99mTc-ECD SPECT is an effective clinical tool to evaluate regional blood flow in subacute cerebral infarction.

Adult↗

PubMed2000

Quantitative analysis of pulmonary neuroendocrine cell distribution of the fetal small airways using double-labeled immunohistochemistry.

Pulmonary neuroendocrine cells (PNECs) are supposed to play an essential role in development of fetal lung and neonatal respiratory adaptation. Some previous studies have suggested the close relation between PNECs and sudden infant death syndrome (SIDS). To investigate how PNECs distribute to the thermal bronchioli of fetal lung may be a clue to clarify this relation. Since it is difficult to distinguish bronchiole from alveolus in fetal lung, we performed double immunostaining with antibody against chromogranin A (CGA) and alpha-smooth muscle actin (SMA) which can make clear distinction between them. In this study, formalin-fixed, paraffin-embedded lung tissues from 18 autopsy cases from 16 to 28 weeks of gestation were assessed. CGA immunopositive cells were counted and the length of basement membranes of terminal bronchioli was measured with computed image analyzer. Density of PNECs was expressed as the number of immunopositive cells per millimeter of basement membrane. Terminal bronchiole stained with SMA was clearly distinguished from alveolus at 16 weeks. With gestational age, CGA immunopositive PNECs were gradually increased in 2 folds by the 25th week. After that, their density wasn't changed significantly until termination. It is suggested that PNECs in terminal bronchiole was playing an important role in morphogenesis of alveolar ducts and alveolar sacks.

Actins↗

PubMed2000

Novel Mn(II)Mn(III)Mn(II) trinuclear complexes with carbohydrate bridges derived from seven-coordinate manganese(II) complexes with N-glycoside.

Reactions of MnX2.nH2O with tris(N-(D-mannosyl)-2-aminoethyl)amine ((D-Man)3-tren), which was formed from D-mannose and tris(2-aminoethyl)amine (tren) in situ, afforded colorless crystals of [Mn((D-Man)3-tren)]X2 (3a, X = Cl; 3b, X = Br; 3c, X = NO3; 3d, X = 1/2SO4). The similar reaction of MnSO4.5H2O with tris(N-(L-rhamnosyl)-2-aminoethyl)amine ((L-Rha)3-tren) gave [Mn((L-Rha)3-tren)]SO4 (4d), where L-rhamnose is 6-deoxy-L-mannose. The structures of 3b and 4d were determined by X-ray crystallography to have a seven-coordinate Mn(II) center ligated by the N-glycoside ligand, (aldose)3-tren, with a C3 helical structure. Three D-mannosyl residues of 3b are arranged in a delta(ob3) configuration around the metal, leading to formation of a cage-type sugar domain in which a water molecule is trapped. In 4d, three L-rhamnosyl moieties are in a delta(lel3) configuration to form a facially opened sugar domain on which a sulfate anion is capping through hydrogen bonding. These structures demonstrated that a configurational switch around the seven-coordinate manganese(II) center occurs depending on its counteranion. Reactions of 3a, 3b, and 4d with 0.5 equiv of Mn(II) salt in the presence of triethylamine yielded reddish orange crystals formulated as [[Mn((aldose)3-tren)]2Mn(H2O)X3.nH2O (5a, aldose = D-Man, X = Cl; 5b, aldose = D-Man, X = Br; 6d, aldose = L-Rha, X = 1/2SO4). The analogous trinuclear complexes 6a (aldose = L-Rha, X = Cl), 6b (aldose = L-Rha, X = Br), and 6c (aldose = L-Rha, X = NO3) were prepared by the one-pot reaction of Mn(II) salts with (L-Rha)3-tren without isolation of the intermediate Mn(II) complexes. X-ray crystallographic studies revealed that 5a, 5b, 6c, and 6d have a linearly ordered trimanganese core, Mn(II)Mn(III)Mn(II), bridged by two carbohydrate residues with Mn-Mn separations of 3.845(2)-3.919(4) A and Mn-Mn-Mn angles of 170.7(1)-173.81(7) degrees. The terminal Mn(II) atoms are seven-coordinate with a distorted mono-face-capped octahedral geometry ligated by the (aldose)3-tren ligand through three oxygen atoms of C-2 hydroxyl groups, three N-glycosidic nitrogen atoms, and a tertiary amino group. The central Mn(III) atoms are five-coordinate ligated by four oxygen atoms of carbohydrate residues in the (aldose)3-tren ligands and one water molecule, resulting in a square-pyramidal geometry. In the bridging part, a beta-aldopyranosyl unit with a chair conformation bridges the two Mn(II)Mn(III) ions with the C-2 mu-alkoxo group and with the C-1 N-glycosidic amino and the C-3 alkoxo groups coordinating to each metal center. These structures could be very useful information in relation to xylose isomerases which promote aldose-ketose isomerization by using divalent dimetal centers such as Mn2+, Mg2+, and Co2+.

Carbohydrates↗

PubMed2000

ELISA for a complexed antigen with a monoclonal antibody blocking reaction with the free antigen-assay-specific for complexed prostate-specific antigen.

We have developed an enzyme-linked immunoassay (ELISA) for serum complexed-antigen (prostate-specific antigen; PSA)(c-PSA) with simultaneous blocking of free-antigen (PSA)(f-PSA). The assay utilizes three different monoclonal antibodies (MAbs) recognising three distinct PSA epitopes. The detection limit was established as 0.19 microg/l (n=20, mean of zero standard+2S.D.) and the average recovery of f-PSA was 98-100%. The within-run and between-day coefficients of variation (CV) ranged from 2.1% to 3.2% and 2.8% to 6.3%, respectively. There was a good correlation between serum c-PSA measured by the present ELISA and PSA-alpha(1)-antichymotrypsin complex (PSA-ACT) concentrations (r=0.991). This method should provide a better tool for discriminating between benign and malignant prostatic disease.

Antibodies, Blocking↗

PubMed2000

Amphipathic structure of theonellapeptolide-Id, a hydrophobic tridecapeptide lactone from the Okinawa marine sponge Theonella swinhoei.

Theonellapeptolide-Id (TNLP), a cyclic tridecapeptide lactone, was crystallized from dimethylformamide-water solution. In the asymmetric unit, two peptide molecules were combined with solvent molecules, and the total molecular weight was over 3000 Dalton. The crystal structure including solvent molecules was finally determined at 0.80 A resolution using synchrotron radiation. The conformations of two independent molecules were similar to each other and were also similar to the previously reported structure (Doi, Ishida, Kobayashi, Deschamps and Flippen-Anderson, 1999, Acta Crystallogr Sect C, 55, 796-798). About 13 hydrated water molecules were found at disordered 19 sites; they were located at a certain region to avoid contact with aliphatic side-chains of peptolide in the crystal. The spatial disposition of the solvent molecules and peptides subsequently caused the formation of the amphipathic layer.

Animals↗

PubMed2000

Irreducible acute anterior dislocation of the shoulder caused by interposed fragment of the anterior glenoid rim.

Failure of manipulative reduction of acute anterior dislocation of the shoulder is extremely rare. A 55-year-old man dislocated his right shoulder when he fell heavily. Initial radiographs and computed tomographs demonstrated an anterior dislocation with fracture of the glenoid rim. Several attempts at closed reduction were unsuccessful. At the time of open reduction, the cause of failure was found to be interposition of a fragment of the anterior inferior glenoid rim in the joint. To prevent redislocation, the fragment was held in place by two Herbert mini bone screws after anatomic reduction, and the ruptured subscapularis was reattached to the lesser tuberosity. Two and a half months after surgery, the shoulder was stable with full range of motion. To the best of our knowledge, this is the first reported case of interposition of a fracture-fragment of the anterior inferior glenoid rim causing failure of reduction.

Bone Screws↗

PubMed2000

Retinal pigment epithelial tear and extensive exudative retinal detachment following blunt trauma.

BACKGROUND: A peripheral retinal pigment epithelial tear and an extensive exudative retinal detachment caused by choroidal leakage from the denuded Bruch's membrane are extremely rare. A peripheral retinal pigment epithelial tear has not been reported in an eye with retinochoroidal folds after blunt ocular trauma. METHODS: Case report. RESULTS: The course of a large nasal peripheral retinal pigment epithelial tear that occurred after blunt ocular trauma in a patient with retinochoroidal folds was followed. The inferior retinal detachment caused by leakage from the denuded Bruch's membrane following the development of the tear gradually worsened. Initial treatment with cryotherapy was ineffective, but the retinal detachment eventually resolved after the patient underwent sclerectomy and sclerostomy. CONCLUSION: A large peripheral retinal pigment epithelial tear can occur in patients with retinochoroidal folds following blunt ocular trauma, and extensive retinal detachment can be induced. Sclerectomy and sclerostomy can be beneficial in patients with an extensive exudative retinal detachment caused by choroidal leakage from the denuded Bruch's membrane.

Adult↗

PubMed2000

Time-dependent changes of decorin in the infarct zone after experimentally induced myocardial infarction in rats: comparison with biglycan.

Decorin, a small dermatan sulphate proteoglycan, has been postulated to interact with other components of the extracellular matrix. We examined time-dependent changes of decorin in the infarct zone after experimentally induced myocardial infarction in rats by Northern blotting, in situ hybridization, and immunohistochemistry. The expression of decorin mRNA was compared to that of biglycan mRNA. Northern blotting demonstrated that the decorin mRNA expression was not increased in the infarct zone on day 2, while increased biglycan mRNA was observed at that time (average 3.1-fold increase). Decorin mRNA expression was increased on day 7, and reached a peak (average 2.2-fold increase) around day 14. Biglycan mRNA expression also reached a peak level around day 14 (average 13.3-fold increase). In situ hybridization revealed that mRNA signals for decorin did not appear in the infarct zone on day 2, while biglycan mRNA signals were observed. Decorin mRNA signals were observed in spindle-shaped mesenchymal cells in the infarct peripheral zone on day 7. The decorin mRNA signals appeared later than those of biglycan. Immunopositive staining for decorin was observed in the infarct zone on day 7. The present results demonstrated a time-dependent increase in decorin mRNA expression in mesenchymal cells in the infarct zone in rats. Decorin mRNA appeared later and was increased to a lower extent in the infarct zone than biglycan mRNA.

Animals↗

PubMed2000

Changes in the liver parenchyma after proton beam radiotherapy: evaluation with MR imaging.

The objective of this study was to describe magnetic resonance (MR) findings with a 1.5T imager for hepatic parenchymal changes after proton beam radiotherapy. Thirty-two patients who received proton radiotherapy with doses of 50-87 Gy underwent MR imaging 1-75 months (mean 22 months) after the start of irradiation. Axial T(2), T(1)-weighted imaging, and a dynamic study after a gadolinium injection were performed. The irradiated areas showed hypointense in T(1)-weighted images, hyperintense in T(2)-weighted images, and intense and prolonged enhancement on the dynamic study (maximum relative enhancement 441.8%+/-263.3 vs. surrounding liver 145.6%+/-67.7, p<0.0001). T(2) values of the irradiated areas were 50.6 to 65.8 msec greater than in the surrounding liver (p<0.005). The values increased with time, being significantly greater 13 months or longer after the beginning of the therapy than after a period of less than 3 months (p<0.05). Pathologic examinations (n = 3) indicated that the irradiated areas were composed of collapsed lobules with hepatic small vein occlusions, and rich extracellular matrices which retained extracellular fluid. MR imaging can demonstrate hepatic parenchymal changes after proton beam radiotherapy, and show the changes are irreversible.

Adult↗

PubMed2000

Pulmonary neuroendocrine cell distribution in sudden infant death syndrome.

The density of pulmonary neuroendocrine cells (PNECs) in 21 sudden infant death syndrome (SIDS) cases, 19 controls, and 25 fetuses was studied morphometrically. Formalin-fixed, paraffin-embedded lung samples were immunostained with antibody against chromogranin A (CGA). The percentage of PNEC-positive airways and the density of PNECs in each airway were calculated in all cases. The density of PNECs was expressed as the number of cells per millimeter of basement membrane. The percentage of PNEC-positive airways reached nearly 100% by term and did not change significantly until 12 months of age in both the SIDS cases and the controls. The density of PNECs also showed a rapid increase in the saccular stage fetus and had its peak of about 4 cells/mm around birth. The density of PNECs, including the standard deviation, was higher in SIDS cases than in controls. The uneven distribution of PNECs may affect respiratory control in SIDS victims.

Journal Article↗

PubMed2000

Vogt-Koyanagi-Harada syndrome in a pregnant patient treated with high-dose systemic corticosteroids.

PURPOSE: Vogt-Koyanagi-Harada (VKH) syndrome is usually treated with high-dose systemic corticosteroids. However, in a pregnant patient with VKH syndrome, the effects of high-dose corticosteroids on the fetus are controversial. We discuss treating VKH syndrome during pregnancy, systemic corticosteroids, and abnormalities in the delivered infant. METHODS: Case report and literature review. RESULTS: A 26-year-old Japanese woman in the 16th week of gestation was diagnosed with VKH syndrome and treated with high-dose systemic prednisolone after the 18th week of gestation. Although the patient's ocular findings gradually improved, a low-birth-weight infant was delivered with epibulbar dermoid, lipodermoids, and preauricular appendages. Although low birth weight might result from systemic prednisolone administration, the anomalies of the infant may have been inherited rather than caused by VKH syndrome and high-dose systemic corticosteroid administration. CONCLUSION: In this case and previously reported cases, VKH syndrome and systemic corticosteroids administered during pregnancy may not precipitate abortion and congenital malformation.

Adult↗

PubMed2000

Bifonazole (Mycospor cream) in the treatment of moccasin-type tinea pedis. Comparison between combination therapy of bifonazole cream + 10% urea ointment (Urepearl) and occlusive dressing therapy with the same agents.

Moccasin-type tinea pedis(MTTP) is a hardly curable superficial dermatomycosis primarily characterized by hyperkeratosis of the sole. In this study, we compared the usefulness of combination therapy of bifonazole (Mycospor cream) + 10% urea ointment (Urepearl) (overlapping application group = group I) with occlusive dressing therapy with the same agents (group II) in the treatment of MTTP, and obtained the following results. (1) The clinical improvement rate (percentage of "marked improvement" and "moderate improvement") was 60.4% in group I and 83.3% in group II. (2) The mycological eradication rate was 48.7% in group I and 82.1% in group II after 4 weeks of treatment and 90.9 and 96.9%, after 12 weeks of treatment, respectively. (3) The clinical utility rate (percentage of "very beneficial" and "beneficial") was 83.3% in group I and 93.8% in group II. These results indicate the superiority of both combination therapy of bifonazole + 10% urea ointment (overlapping application group) and occlusive dressing therapy with the same agents in terms of efficacy and safety for the treatment of MTTP, and suggest that they can be recommended for treatment of patients for whom it is difficult to use oral antimycotic agents or for patients who fail to respond to oral medications alone.

Administration, Topical↗

PubMed2000

Determination of optimal conditions for the immobilization of cells in a cell capture enzyme immunoassay (CC-EIA) by a simple Geimsa assay.

To determine the optimal conditions for the immobilization of cells in a cell capture enzyme immunoassay (CC-EIA), the most suitable diluent, and the optimal pH, temperature and period of incubation were examined using WI-38, a human embryonic lung fibroblast cell line. For the evaluation, we devised a simple Giemsa assay method, in which immobilized cells on a microplate were stained with Giemsa solution, the stained dye was eluted with ethanol after washing the plate, and the optimal density (O.D.) was measured at wavelength 620 nm. The optimal conditions for the immobilization were determined to be treatment with 5% formalin in phosphate-buffered saline (PBS) (pH 7.2) for 15 minutes at room temperature, which were confirmed to be suitable for the measurement of cell associated collagen by CC-EIA. Additionally, we found that the simple Giemsa staining method was also useful for evaluating the number of immobilized cells on the microplate after CC-EIA.

Azure Stains↗

PubMed2000

The 7alpha-methoxy substituent in cephem or oxacephem antibiotics enhances in vivo anti-Helicobacter felis activity in mice after oral administration.

The in vivo antibacterial activities of 7alpha-methoxy-cephems or 7alpha-methoxy-1-oxacephems and their demethoxy congeners after oral administration were compared in a mouse model of gastric infection with Helicobacter felis. The MICs of all four pairs of compounds with and without the 7alpha-methoxy substituent were within one two-fold dilution for H. felis and Helicobacter pylori, but the 7alpha-methoxy compounds were at least four-fold more active at bacterial eradication than their demethoxy congeners. Since these compounds are not absorbed after oral administration, they are likely to have gained direct access to the bacteria from the gastric cavity. Thus the 7alpha-methoxy substituent may enhance in vivo activity by promoting the gastric mucus permeability of the compounds or by allowing the compounds to remain longer in the gastric cavity.

Animals↗

PubMed2000

Prediction of acute embolic stroke outcome after local intraarterial thrombolysis: value of pretreatment and posttreatment 99mTc-ethyl cysteinate dimer single photon emission computed tomography.

The aim of this study was to investigate the efficacy of pre- and posttreatment 99mTc-ethyl cysteinate dimer (99mTc-ECD) single photon emission computed tomography (SPECT) for predicting the ischemic outcome of embolic middle cerebral artery occlusion after treatment with local intraarterial thrombolysis. The authors examined 28 patients with a moderately ischemic area (ratio of affected regional activity to cerebellar activity (A/C ratio) of 0.4 to 0.7) determined using pretreatment SPECT, and with complete recanalization within 6 hours. Posttreatment dynamic and static SPECT studies were performed immediately after thrombolysis. The extent of the affected area outlined on pretreatment SPECT was used for the posttreatment SPECT images, and A/C ratios were calculated. The relative retention ratio of 99mTc-ECD in the affected area was also analyzed using posttreatment dynamic SPECT. Fourteen patients either without infarction or with small subcortical and basal ganglial infarction, 11 patients with medium or large cortical infarction, and 3 patients with hemorrhage were identified by follow-up computed tomography. Ischemic outcome correlated with the relative retention ratio of 99mTc-ECD more closely than either the pre- or posttreatment A/C ratios. In particular, a threshold value for the development of hemorrhage was distinct only in the relative retention ratio of 99mTc-ECD. Pretreatment 99mTc-ECD SPECT did not always predict the occurrence of hemorrhagic transformation, whereas dynamic 99mTc-ECD SPECT performed immediately after thrombolysis allowed clear identification of patients at risk for hemorrhagic transformation.

Adult↗

PubMed2000

Neurological grades of patients with poor-grade subarachnoid hemorrhage improve after short-term pretreatment.

OBJECTIVE: Short-term pretreatment of patients with subarachnoid hemorrhage, but without hematomas causing mass effect, who presented in poor neurological condition at admission was evaluated as a protocol for the selection of candidates for radical surgery. METHODS: One hundred-three patients were pretreated for 12 hours with control of blood pressure and intracranial pressure, using diuretic agents and/or ventricular drainage. RESULTS: Neurological improvement was observed for 32 of 47 patients in Grade IV at admission and 23 of 56 patients in Grade V (P < 0.01). Hydrocephalus requiring drainage was more common (P < 0.05) and the interval between onset and admission was shorter (P < 0.01) for the improved group. Clipping surgery was performed for all patients in Grade III or better and for patients in Grade IV who were less than 75 years of age and without systemic complications, i.e., 38 of 47 patients in Grade IV and 16 of 56 patients in Grade V at admission. Good outcomes (defined as moderately disabled or better on the Glasgow Outcome Scale) were achieved by 34 of 38 patients in Grade IV and 10 of 16 patients in Grade V (P < 0.01). The proportion of patients in Grade IV after pretreatment was lower for Grade IV (2 of 38 patients) than for Grade V (9 of 16 patients) (P < 0.00001). However, none of the 49 patients who underwent nonsurgical treatment achieved good outcomes. CONCLUSION: Our protocol may be beneficial for the selection of candidates for radical surgery among patients with subarachnoid hemorrhage but without hematomas who are in poor neurological condition at admission and for the improvement of postoperative outcomes.

Aged↗

PubMed2000

Histopathologic abnormalities in rabbit retina after intravitreous injection of expansive gases and air.

PURPOSE: To evaluate histopathologic retinal changes in rabbit eyes after injection of pure perfluoropropane (C3F8) gas, pure sulfur hexafluoride (SF6) gas, or air into the vitreous cavity. METHODS: Air, C3F8 gas, or SF6 gas (0.4 mL each) were injected into rabbit vitreous cavities. Two, 4, and 6 weeks later, light and electron microscopic examinations were conducted, and the immunohistochemical localization of glutamate in the retina was studied. Noninjected eyes served as controls. RESULTS: At all time points, thinning or disappearance of the outer plexiform layer in the superior retina in eyes that received C3F8 gas was found; the inferior retina was the same as in controls. In eyes that received SF6 gas or air, light and electron microscopy showed that the superior and inferior retina were the same as in controls at all time points. Immunohistochemical examination showed abnormal glutamate distribution of the superior retina in eyes injected with C3F8 gas, SF6 gas, or air. However, glutamate distribution was the same as in controls in the inferior retina in eyes injected with C3F8 gas, SF6 gas, or air. CONCLUSIONS: Retinal tamponade using intraocular gases induces histopathologic retinal changes in the superior retina of the rabbit eye, where the gases are in continuous contact with the eye.

Air↗

PubMed2000

Histopathologic retinal changes with intravitreous fluorosilicone oil in rabbit eyes.

BACKGROUND: Fluorosilicone oil (FSiO, 1,000-10,000 centistokes), which has a higher density (1.29 g/cm3) than vitreous gel, is useful as an operative tool and a tamponade for the inferior retina during difficult retinal detachment surgery. The occurrence of histopathologic retinal changes after injection of FSiO into the vitreous cavity is controversial. METHODS: Retinas obtained from 18 rabbits were evaluated histopathologically within 8 weeks of injection into the vitreous cavity of purified FSiO or balanced salt solution as control in phakic eyes. The histopathologic retinal changes caused by FSiO were compared with those of previously reported high-density hydrophobic vitreous substitutes, such as silicone-fluorosilicone copolymer oil (SiFO) and perfluorocarbon liquids. RESULTS: By light and electron microscopy, all retinas injected with FSiO were the same as control retinas within 2 weeks of the injection, but the outer plexiform layer disappeared from the inferior retina 4 weeks after injection. The receptor cell nuclei migrated to the photoreceptor layer in the inferior retina 8 weeks after injection. However, no preretinal membrane, including foam cells, was found in any eye injected with FSiO. CONCLUSION: FSiO may be useful as a temporary vitreous substitute in difficult inferior retinal detachments.

Animals↗