Biomedical subjects

H Abe

Publications and source records attributed to H Abe.

At least 145 records · Page 8Linked to original sources

PubMed2000

(1S)-1-[(4R)-2,2-dimethyl-1,3-dioxolan+-4-yl][-2-hydroxyethylamm onium benzoate, a versatile building block for chiral 2-aminoalkanols: concise synthesis and application to nelfinavir, a potent HIV-protease inhibitor.

A concise synthesis of a versatile chiral C4 building block for 2-aminoalkanols, (1S)-1-[(4R)-2,2-dimethyl-1,3-dioxolan-4-yl]-2-hydroxyethylammo nium benzoate (1a), was described. 1 (1a and its enantiomer 1b) acted as four stereoisomers of optically active 2-amino-1,3,4-butanetriol. The versatility of 1 was demonstrated by its application to the practical synthesis of nelfinavir (2), a potent HIV-protease inhibitor, as well as by the stereospecific synthesis of three diastereomers of 2.

Amino Alcohols↗

PubMed2000

Fast separation of oligonucleotide and triplet repeat DNA on a microfabricated capillary electrophoresis device and capillary electrophoresis.

A laser-induced fluorescence detection system coupled with a highly sensitive silicon-intensified target (SIT) camera is successfully applied to the imaging of a band for DNA fragment labeling by fluorescence dye in a microchannel, and to the visualizing of the separation process on a microfabricated chip. We demonstrated that an only 6 mm separation channel is sufficient for the separation of triplet repeat DNA fragment and DNA molecular marker within only 12 s. The separation using the microfabricated capillary electrophoresis device is confirmed to be at least 18 times faster than the same separation carried out by conventional capillary electrophoresis with 24.5 cm effective length. The use of a short capillary with 8.5 cm effective length is also efficient for fast separation of DNA; however, the microchip technology is even faster than capillary electrophoresis using a short capillary.

DNA↗

PubMed2000

Intracellular pH modulation of ADF/cofilin proteins.

The ADF/cofilin (AC) proteins are necessary for the high rates of actin filament turnover seen in vivo. Their regulation is complex enough to underlie the precision in filament dynamics needed by stimulated cells. Disassembly of actin by AC proteins is inhibited in vitro by phosphorylation of ser3 and pH<7.1. This study of Swiss 3T3 cells demonstrates that pH also affects AC behavior in vivo: (1) Wounded cells show pH-dependent AC translocation to alkaline-induced ruffling membrane; (2) The Triton extractable (soluble) ADF from Swiss 3T3 cells decreases from 42+/-4% to 23+/-4% when the intracellular pH (pH(i)) is reduced from 7.4 to 6.6; (3) Covariance and colocalization analyses of immunostained endogenous proteins show that ADF partitions more with monomeric actin and less with polymeric actin when pH(i) increases. However, the distribution of cofilin, a less pH-sensitive AC in vitro, does not change with pH; (4) Only the unphosphorylatable AC mutant (A3), when overexpressed as a GFP chimera, uniquely produces aberrant cellular phenotypes and only if the pH is shifted from 7.1 to 6.6 or 7.4. A mechanism is proposed that explains why AC(A3)-GFP and AC(wt)-GFP chimeras generate different phenotypes in response to pH changes. Phospho-AC levels increase with cell density, and in motile cells, phospho-AC increases with alkalization, suggesting a homeostatic mechanism that compensates for increased AC activity and filament turnover. These results show that the behavior of AC proteins with pH-sensitivity in vitro is affected by pH in vivo.

3T3 Cells↗

PubMed2000

Non-contrast-enhanced MR angiography using 3D ECG-synchronized half-Fourier fast spin echo.

A non-contrast-enhanced three-dimensional (3D) magnetic resonance angiography (MRA) technique, which acquires images in a reasonably short scanning time and requires no contrast agent, is developed. An electrocardiographically (ECG) synchronized 3D half-Fourier fast spin-echo (FSE) technique with an appropriate ECG delay time for every slice encoding in 3D terms was used to examine the thoracic and iliac regions in 16 healthy volunteers at both 0.5 and 1.5 T. Prior to each 3D fresh blood imaging (FBI) experiment, an ECG preparation (ECG-prep) scan was acquired, and an appropriate ECG triggering time was selected for 3D FBI acquisition to optimize visualization of the vessel of interest. In the thoracic and abdominal regions, good-quality 3D MRA images were obtained. Furthermore, the weighted subtraction of two images in different phases provides contrast enhancement between arteries and veins.

Adult↗

PubMed2000

Factors relating to place of death of Japanese people from a small town in a rural area.

The objective of our retrospective study was to clarify factors relating to place of death of Japanese people from a small town in a rural area who had been bedridden for at least one week before dying. The caregivers of subjects aged 40 and above who died during a three-year period were surveyed by trained interviewers. Of 352 subjects who died, 312 caregivers responded and agreed to a face-to-face interview. A total of 213 subjects were considered as an eligible sample. The main outcome measures were odds ratios for death at home in relation to age, pain, cause of death, and home visit service. One hundred and two people died at home, while 112 people died in a hospital. Multivariate logistic regression analysis showed that the probability of home death increased with age of the bedridden, lack of pain during the bedridden period, not having cancer as a cause of death, having senility as a cause of death, and receiving regular home visits by a Public Health Nurse. In conclusion, expansion of the home visit programs by Public Health Nurses may enable people to die at home as they so desire. Further prospective research is needed to explore the association between the attitude toward terminal care and the place of death.

Adult↗

PubMed2000

MRI at 1.5 T of intramedullary ependymoma and classification of pattern of contrast enhancement.

We retrospectively reviewed the MRI findings in 28 patients with an intramedullary spinal cord ependymoma who underwent surgical treatment. There were 26 tumours in the cervical and two in the thoracic spine. T1- and T2-weighted and contrast-enhanced images at 1.5 T were obtained in all cases. T1-weighted imaging showed solid tumour as isointense in 13 patients, high-signal in ten and low signal in five. In contrast, T2-weighted imaging showed all tumours as high signal. Contrast enhancement was heterogeneous 13 patients, homogeneous 10, heterogeneous with cyst wall enhancement in three, and a nodule on a cyst wall was seen in two. Cases with these latter patterns require careful differential diagnosis from astrocytoma or haemangioblastoma.

Adolescent↗

PubMed2000

Biosynthesis of poly(3-hydroxybutyrate-co-3-hydroxyalkanoates) by recombinant bacteria expressing the PHA synthase gene phaC1 from Pseudomonas sp. 61-3.

Pseudomonas sp. 61-3 accumulated a blend of poly(3-hydroxybutyrate) [P(3HB)] homopolymer and a random copolymer consisting of 3-hydroxyalkanoate (3HA) units of 4-12 carbon atoms. The genes encoding beta-ketothiolase (PhbA(Re)) and NADPH-dependent acetoacetyl-CoA reductase (PhbB(Re)) from Ralstonia eutropha were expressed under the control of promoters for Pseudomonas sp. 61-3 pha locus or R. eutropha phb operon together with phaC1(Ps) gene (PHA synthase 1 gene) from Pseudomonas sp. 61-3 in PHA-negative mutants P. putida GPp104 and R. eutropha PHB(-4) to produce copolyesters [P(3HB-co-3HA)] consisting of 3HB and medium-chain-length 3HA units of 6-12 carbon atoms. The introduction of the three genes into GPp104 strain conferred the ability to synthesize P(3HB-co-3HA) with relatively high 3HB compositions (up to 49 mol%) from gluconate and alkanoates, although 3HB units were not incorporated at all or at a very low fraction (3 mol%) into copolyesters by the strain carrying phaC1Ps gene only. In addition, recombinant strains of R. eutropha PHB(-4) produced P(3HB-co-3HA) with higher 3HB fractions from alkanoates and plant oils than those from recombinant GPp104 strains. One of the recombinant strains, R. eutropha PHB(-4)/ pJKSc46-pha, in which all the genes introduced were expressed under the control of the native promoter for Pseudomonas sp. 61-3 pha locus, accumulated P(3HB-co-3HA) copolyester with a very high 3HB fraction (85 mol%) from palm oil. The nuclear magnetic resonance analyses showed that the copolyesters obtained here were random copolymers of 3HB and 3HA units.

Acyltransferases↗

PubMed2000

Factors in neurological deterioration and role of surgical treatment in lumbosacral spinal lipoma.

The purpose of this study was to determine factors that might be involved in neurological deterioration and the role of surgical treatment in patients with lumbosacral spinal lipoma. Pre- and postoperative courses of 34 patients were retrospectively analyzed. The age at surgery ranged from 1 month to 47 years. The records of preoperative neurological status indicated that older patients had more severe deficits, while all 8 asymptomatic patients were under 5 years of age. Motor deficits were noted in 9 patients, in 7 of whom the lipoma extended cranially beyond the L5 level. Transitional-type lipomas were accompanied by more severe deficits (asymptomatic 1, symptomatic 17) than other types (asymptomatic 7, symptomatic 9). Postoperative follow-up periods ranged from 5 months to 13 years. During these periods, 7 of the 8 asymptomatic patients remained neurologically intact. Nine of the 26 symptomatic patients improved. Age, extension of the lipoma in the spinal canal and type of lipoma will influence the preoperative neurological status of the patients. Early untethering surgery is recommended in patients with large lipomas extending beyond the L5 level.

Adolescent↗

PubMed2000

Molecular structure of a novel gypsy-Ty3-like retrotransposon (Kabuki) and nested retrotransposable elements on the W chromosome of the silkworm Bombyx mori.

We previously characterized a female-specific randomly amplified polymorphic DNA (RAPD), designated W-Kabuki, derived from the W chromosome of the silkworm, Bombyx mori. To further analyze the W chromosome of B. mori, we obtained a lambda phage clone which contains the W-Kabuki RAPD sequence and sequenced the 18.1-kb DNA insert. We found that this DNA comprises a nested structure of at least seven elements; three retrotransposons, two retroposons, one functionally unknown insertion, and one Bombyx repetitive sequence. The non-LTR retrotransposon BMC1, the retroposon Bm1, a functionally unknown inserted DNA (FUI), and a copia-like LTR retrotransposon (Yokozuma) are themselves inserted into a novel gypsy-Ty3-like LTR retrotransposon, named Kabuki. Furthermore, this Kabuki element is itself inserted into another copy of Bm1. The BMCI and Yokozuna elements inserted in the Kabuki sequence are intact. Moreover, the Kabuki element is largely intact. These results suggest that many retrotransposable elements have accumulated on the W chromosome, and these elements are expected to evolve more slowly than those on other chromosomes.

Amino Acid Sequence↗

PubMed2000

Neovascularization (angiogenesis) after revascularization in moyamoya disease. Which technique is most useful for moyamoya disease?

The effects of direct and indirect revascularization for moyamoya disease were analyzed for each donor artery to determine which surgical procedure is most useful for the induction of neovascularization. In the past 12 years, 85 patients with moyamoya disease were surgically treated by combined surgery consisting of indirect revascularization via encephalo-duro-arterio-myo-synangiosis (EDAMS) and direct revascularization via the superficial temporal artery and the middle cerebral artery (STA-MCA) bypass. Among those patients, the post-operative changes in digital subtraction angiography were examined in 56 sides, including 34 sides in paediatric cases and 22 sides in adult cases. The neovascularization after indirect revascularization using the 1) superficial temporal artery (skin), 2) middle meningeal artery (dura mater), 3) deep temporal artery (temporal muscle) was analyzed. As results, in paediatric cases, the deep temporal artery and middle meningeal artery induced good neovascularization. However, the induction of neovascularization from the superficial temporal artery was not always good in most pediatric and adult cases. On the other hand, the direct bypass was useful in 90% of adult cases. In indirect revascularization surgery for moyamoya disease, the temporal muscle (the deep temporal artery) and the dura mater (the middle meningeal artery) are useful donors to the ischemic brain. The simple encephalo-arterio-synangiosis is not always effective. The direct bypass is a useful technique for adult moyamoya disease.

Adult↗

PubMed2000

Operative record using intraoperative digital data in neurosurgery.

BACKGROUND: The purpose of this study was to develop a new method for more efficient and accurate operative records using intra-operative digital data in neurosurgery, including macroscopic procedures and microscopic procedures under an operating microscope. METHODS: Macroscopic procedures were recorded using a digital camera and microscopic procedures were also recorded using a microdigital camera attached to an operating microscope. Operative records were then recorded digitally and filed in a computer using image retouch software and database base software. FINDINGS: The time necessary for editing of the digital data and completing the record was less than 30 minutes. Once these operative records are digitally filed, they are easily transferred and used as database. Using digital operative records along with digital photography, neurosurgeons can document their procedures more accurately and efficiently than by the conventional method (handwriting). INTERPRETATION: A complete digital operative record is not only accurate but also time saving. Construction of a database, data transfer and desktop publishing can be achieved using the intra-operative data, including intra-operative photographs.

Humans↗

PubMed2000

The relationship between apoptosis and splenocyte depletion in rats following ethanol treatment.

Splenocyte depletion observed in chronic ethanol-treated rats (ETRs) was studied in relation to apoptosis. The rats were fed with ethanol in a Liber-DeCarli liquid diet (36% of total calories as ethanol) for 7 weeks. Spleens of ETRs and control rats were examined by the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) method, immunohistochemistry using anti-rat p53 and RM4 (specific for macrophages) monoclonal antibodies, and transmission electron microscopy (TEM). The splenic white pulp in ETRs decreased in size and showed a moth-eaten appearance because of the severe depletion of splenocytes. Most TUNEL-positive cells aggregated into clusters or nests and were not isolated in the white pulp of ETRs. The site of RM4 immunoreactivity was consistent with that of clusters of TUNEL-positive cells. The p53 immunoreactivity was observed in apoptotic splenocytes that were isolated or phagocytosed by macrophages. TEM study revealed the increase in tingible body macrophages phagocytosing apoptotic splenocytes in their cytoplasm in ETRs. Chronic ethanol intake certainly induces apoptosis in splenic white pulps, and tingible body macrophages act as both sentinels and scavengers of apoptotic splenocytes expressing p53.

Animals↗

PubMed2000

Measurement of microcirculation in the optic nerve head by laser speckle flowgraphy and scanning laser Doppler flowmetry.

PURPOSE: To evaluate and compare blood flow measurements by laser speckle flowgraphy and scanning laser Doppler flowmetry in the optic nerve head of normal volunteers. METHODS: This prospective study included 60 eyes of 60 normal volunteers (50.0 years; range, 21 to 77 years). Measurements were taken at the temporal neuroretinal rim away from visible vessels. The square blur rate, a quantitative index of relative blood velocity, was measured by laser speckle flowgraphy. Using scanning laser Doppler flowmetry, volume, flow, and velocity were measured at the same neuroretinal rim locations. RESULTS: The average square blur rate, volume, flow, and velocity were 7.11 +/- 1.65, 7.74 +/- 3.19, 151.85 +/- 70.63, and 0.53 +/- 0. 23 arbitrary units, respectively (n = 60). Square blur rate correlated significantly with flow and velocity (r =.361, P =.005; r =.359, P =.005, respectively). However, there was no significant correlation between square blur rate and volume (r =.101, P =.441). Although square blur rate decreased significantly with increasing age (r = -.375, P =.003), volume, flow, or velocity showed no significant correlation with age (r = -.249, P =.054; r = -.166, P =. 205; r = -.143, P =.275, respectively). Square blur rate also decreased significantly with mean blood pressure (r = -.315, P =. 014), but volume, flow, or velocity showed no significant correlation with mean blood pressure (r = -.159, P =.225; r = -.059, P =.654; r = -.043, P =.742, respectively). CONCLUSION: We found only a weak correlation between the blood flow indexes, as measured by laser speckle flowgraphy and scanning laser Doppler flowmetry because of basic differences in the principles of measurement.

Adult↗

PubMed2000

Mizuo phenomenon observed by scanning laser ophthalmoscopy in a patient with Oguchi disease.

PURPOSE: To elucidate the origin of the abnormal fundus reflex in Oguchi disease. METHODS: The ocular fundus of a 63-year-old woman who showed a homozygous arrestin 1147delA mutation was observed by scanning laser ophthalmoscopy with the use of an argon blue laser (wavelength, 488 nm), a helium-neon laser (633 nm), and an infrared laser (780 nm). RESULTS: Diffuse, fine, white particles, which do not exist in normal subjects, were clearly demonstrated only with the helium-neon laser. After 4-hour dark adaptation, the abnormal particles disappeared, but then they reappeared gradually during 30 minutes of light adaptation, in accordance with the golden metallic reflex. CONCLUSION: The white particles found by helium-neon laser could be the origin of the abnormal fundus reflex in Oguchi disease.

Arrestin↗

PubMed2000

Measurement of microcirculation in optic nerve head by laser speckle flowgraphy in normal volunteers.

PURPOSE: To report blood flow in the optic nerve head between the right and left eyes or the superior and inferior neuroretinal rims in normal volunteers using laser speckle flowgraphy. METHODS: This prospective study included 120 eyes of 60 normal volunteers (mean age, 50.0 +/- 16.9 years; range, 21 to 77 years). The square blur rate was measured by laser speckle flowgraphy (Kyushu Institute of Technology, Iizuka, Japan). The sequence of eye measurements was randomized. In each eye, measurements were taken at the neuroretinal rim away from visible vessels. Linear regression analysis, paired two-tailed t test, and two-way analysis of variance were used for statistical analysis. P values less than.05 were accepted as statistically significant. RESULTS: There was a significant correlation in square blur rate between the right and left eyes (r = 0.587, P <.001). Square blur rate in the superior temporal neuroretinal rim significantly correlated with that in the inferior temporal neuroretinal rim in each of the right (r = 0.546, P <.001) and left (r = 0.465, P <.001) eyes. Square blur rate in the right eye was higher than that in the left eye (P =.049). Square blur rate in the superior neuroretinal rim was higher than that in the inferior neuroretinal rim in both the right (P =.035) and left (P =. 005) eyes. CONCLUSION: There were statistically significant differences of optic nerve head blood flow in normal volunteers using laser speckle flowgraphy between the right and left eyes and between the superior and inferior temporal neuroretinal rims. These normal data can be used for understanding physiological ocular hemodynamics.

Adult↗

PubMed2000

Observation of human corneal and scleral collagen fibrils by atomic force microscopy

Purpose: We attempted to analyze the three-dimensional ultrastructure of human corneal and scleral collagen fibrils with an atomic force microscope (AFM).Methods: A normal eye removed from a 66-year-old male was used in the study. Suspended corneal and scleral collagen fibrils were individually attached to glass slides by centrifugation. These collagen fibrils were air-dried and observed with a noncontact mode AFM in air.Results: AFM imaging provided information on the surface topography of both corneal and scleral collagen fibrils. The corneal collagen fibrils had a height of 11.9 +/- 1.0 (mean +/- standard deviation) nm and the scleral fibrils of 82.5 +/- 35.6 nm. A periodic banding pattern of grooves and ridges was clearly found in both types of fibrils: the D-periodicity and the groove depth were 65.7 +/- 0.8 nm and 1.46 +/- 0.50 nm in the corneal fibrils, and 67.3 +/- 1.1 nm and 6.16 +/- 1. 23 nm in the scleral fibrils.Conclusions: Surface topographic images of human corneal and scleral collagen fibrils were clearly obtained with the AFM. This technique provides quantitative information on the surface morphology of the collagen fibrils at high resolution.

Journal Article↗

PubMed2000

Influence of autonomic tone on the filtered QRS duration from signal averaged electrocardiograms in healthy volunteers.

We recently reported that signal averaged electrocardiograms (SAECG) measurements possess a circadian rhythm and are closely related to heart rate or heart rate variability in healthy volunteers. This study determines the influence of autonomic tone on the filtered QRS (f-QRS) duration from SAECG by using pharmacologic autonomic blockade and exercise in healthy volunteers. Eleven healthy male volunteers were studied. Three protocols were designed to study the effects of exercise (Ex) under control conditions, beta adrenergic blockade or double blockade. SAECGs and heart rate variability (LF and HF: low and high frequency power, LF/HF ratio) were determined from Holter recordings. Ex significantly decreased the f-QRS duration and HF and significantly increased heart rate and LF/HF. Ex during beta adrenergic blockade significantly increased heart rate and decreased f-QRS duration and HF, but did not change LF/HF. Ex during double blockade did not affect the f-QRS duration, HF, or LF/HF. The changes in f-QRS duration induced during Ex, autonomic blockade, or both were inversely correlated with changes in heart rate and LF/HF and positively correlated with changes in HF. These data suggest that f-QRS duration in healthy subjects is shortened by Ex with increased sympathetic tone or decreased parasympathetic tone or the combination.

Adrenergic beta-Antagonists↗

PubMed2000

Chronological changes in MRI findings of spinal dural arteriovenous fistula.

BACKGROUND: Intramedullary high-intensity changes on T2-weighted magnetic resonance images (MRI) occur in patients with spinal dural arteriovenous fistulas (AVF). Reduction of the high-intensity area after treatment has been noted; however, there are still questions about whether the change is related to preoperative clinical grade, postoperative improvement, or efficacy of treatment. This study tried to clarify the relationship between chronological changes in the high intensity area with the treatment and clinical course. METHODS: Chronological changes in an intramedullary high-intensity area after surgery were retrospectively analyzed in recent 13 patients with spinal dural AVFs who were treated and followed by MRI. RESULTS: Preoperative intramedullary high-intensity areas were observed on T2-weighted images in all cases. The extent of the high-intensity area correlated with preoperative neurological deficits. The intramedullary high-intensity area was reduced or diminished after successful interruption of AVFs. The high-intensity area started to decrease within 1 to 4 months after treatment in all patients, and disappeared at 2 weeks to 23 months in seven patients. The reduction may suggest interruption of the fistula and improvement of venous circulation, but was not always correlated to clinical improvement. The intramedullary high-intensity areas rapidly disappeared in two patients, but did not clearly correspond to the clinical improvement. CONCLUSIONS: The time course of postoperative MRI changes is helpful for evaluating the efficacy of treatment after surgery for spinal dural AVFs.

Adult↗