PubMed Health⌕ Search

Biomedical subjects

K Yaguchi

Publications and source records attributed to K Yaguchi.

At least 19 recordsLinked to original sources
PubMed1991

Construction and nucleotide sequence analysis of an infectious DNA clone of the autonomous parvovirus, mink enteritis virus.

We have cloned the replicative form (RF-) DNA of mink enteritis virus (MEV), constructed an infectious recombinant plasmid containing MEV DNA and determined the nucleotide sequence of the cloned MEV DNA. RF-DNAs were detected and infectious virus was generated when the recombinant plasmid containing the entire MEV genome was introduced into feline kidney cell cultures. The MEV genome was 5094 nucleotides (nt) in length; the 3' end of the virion strand contained a 205 nt palindromic sequence and the 5' end a 62 nt palindromic sequence that could assume Y- and U-shaped configurations, respectively. The 5' end of the virion strand had a direct repeat of 61 nt at the carboxyl terminus of the capsid protein gene. The organization of the MEV genome is similar to those of canine parvovirus (CPV) and feline panleukopenia virus (FPLV); there are two large open reading frames (ORFs), one in the 3' half and the other in the 5' half of the genome, with coding capacities of 668 and 722 amino acid residues, respectively. Both are in the same reading frame and no significant ORFs are apparent in the virion strand (negative-sense strand). Possible functional promoter motifs are located at map unit (m.u.) 4.5 and m.u. 40, and a possible functional poly(A) signal is located at m.u. 96. The nucleotide and amino acid sequence homology with CPV and FPLV is greater than 98%, consistent with the hypothesis that MEV and CPV are host-range variants of FPLV.

Amino Acid Sequence↗
PubMed1991

Identification of pre- and postcentral gyri on CT and MR images on the basis of the medullary pattern of cerebral white matter.

The authors illustrate a new method to identify the pre- and postcentral gyri on computed tomographic (CT) and magnetic resonance (MR) images of the brain on the basis of the pattern of the medullary branches of the cerebral white matter. The most commonly used method to identify the gyri depends on recognition of the central sulcus by surface arrangement of the sulci. The two methods were compared by analysis of CT images of 104 subjects who had normal findings (age range, newborn to 60 years; 57 males and 47 females). The usefulness of the new method was also determined in angiographic studies of nine patients with space-occupying lesions. The method is especially helpful for identification of gyri on the lower level of the centrum semiovale and if space-occupying lesions are present that may result in a blurred depiction of sulci. Since MR imaging depicts the medullary branches more clearly than does CT, this new method should facilitate identification of the gyri with either modality.

Adolescent↗
PubMed1990

Left-right asymmetry of the temporal and parietal regions in children: based on the medullary pattern of cerebral white matter.

Lateralization of the posterior temporal lobe and inferior parietal lobule in childhood was studied on CT of 276 cases and compared with those in adulthood of 371 cases. CT images were analyzed based on the morphological features of medullary branches of the cerebral white matter. In children below 5 years of age, the left planum temporale was already more posteriorly located than the right in 56%, while the right was more so in 21%. The asymmetry of the middle temporal gyrus was similar to those of the planum temporale. The folding of the inferior parietal lobule was extensive and intricate on the left side in 63% and on the right side in 8% of children, almost identical to those in the adult. The visualization rates of the intraparietal sulcus were lower compared to those of the adult, but the higher visualization of the left side was a common tendency regardless of age. These alterations in left-right asymmetry seemed to be a morphologic substratum indicating the processes of localization of auditory function to those association areas.

Adult↗
PubMed1990

Hb Fukutomi [alpha 126(H9)Asp----Val]: a new hemoglobin variant with high oxygen affinity.

Hb Fukutomi [alpha 126(H9)Asp----Val], a new hemoglobin variant with a high affinity for oxygen (log P50 = 0.201 at pH 7.0, normal = 1.087) was detected in a Japanese male during a screening survey. The amino acid substitution is located in the alpha 1 beta 1 contact of the tetramic molecule. Like other variants of the high oxygen affinity type Hb Fukutomi showed increased resistance to auto-oxidation. The tryptic peptide alpha T-13, that usually forms part of the trypsin-resistant core of the alpha chain, was cleaved off by trypsin in the new variant and released into the soluble fraction.

Amino Acid Sequence↗
PubMed1990

[CT findings of watershed infarction; comparison of 123I-IMP SPECT and IV-DSA].

A watershed infarction is a specific type of a cerebral infarction. This occurs at the border zone between major cerebral arteries. Its CT findings are characteristic as a wedge shaped low density appearing either in the superior frontal region (watershed between anterior and middle and posterior cerebral artery), and always involving the deep white matter onto the ventricle wall. Even though the CT feature is small, a patient, without exception, suffers from neurologic deficit. We studied four cases of a watershed infarction on X-ray CT and compared with 123I-IMP SPECT. DSA was also made to demonstrate an obstruction of an artery which was usually found at the more proximal segment then what we expected from the CT feature. The findings on the 123I-IMP SPECT were better predictable of neurologic symptoms and they were larger in extent than the CT findings.

Aged↗
PubMed1988

A new screening test for dementia.

The purpose of this study is to develop a new screening test for detecting the demented elderly in the early stage in communities. The test is easy to apply for consultation, guidance and care and is capable of administering differential diagnoses. Based on the 9 dementia rating scales used in Japan, Europe and the U.S., a new test was completed after investigating and modifying the design 5 times. The test consists of 20 items. This test was given to 203 subjects (59 males and 144 females) including normal elderly as well as those suspected of suffering from dementia. The internal consistency, reliability and validity were studied using clinical diagnoses (diagnostic criteria of Diagnostic and Statistical Manual of Mental Disorders, Third Edition (DSM-III) and Karasawa's Criteria for Judging Senility), Hasegawa's Dementia Rating Scale and Mental Status Questionnaire (MSQ) as external criteria. The present test was confirmed to have sufficient effectiveness as the screening test for dementia.

Aged↗
PubMed1986

Left-right asymmetry in the temporal and parietal region based on the medullary pattern of cerebral white matter.

Left-to-right differences in cerebral structures of the posterior temporal and inferior parietal region were investigated in CT examinations from 500 cases, by anatomic analysis based on the medullary branches of cerebral white matter. On the left side, the planum temporale and middle temporal gyrus were positioned more posteriorly, the intraparietal sulcus was deeper and lower, and the folding of the inferior parietal lobule was more extensive. The lateralization of the planum temporale diminished gradually from 19 years of age downwards. An anatomic analysis of the medullary branches succeeded in revealing the cerebral asymmetry and is expected to be useful in magnetic resonance imaging.

Adolescent↗
PubMed1985

Surgically confirmed myelographic classification of congenital intraspinal lipoma in the lumbosacral region.

Twenty-four cases of histologically confirmed congenital intraspinal lipoma of the lumbosacral region were studied by means of myelography with metrizamide. The findings were compared with intraoperative observations. Myelography with metrizamide clearly revealed the detailed intrathecal structures and allowed a classification of intraspinal lipomas into four types, in terms of their insertion into the conus medullaris: dorsal type, either with direct or indirect (via an intrathecal stalk) insertion of the extrathecal lipoma into the dorsal aspect of the conus medullaris; caudal type; combined type; and filar lipoma. Based on our surgical experience in untethering and decompression of the lesions, the classification was found to be useful in designing a safe and effective surgical procedure which minimized all possible trauma to the intrathecal neural structures.

Adolescent↗
PubMed1985

Computed tomography of cerebral infarction along the distribution of the basal perforating arteries. Part II: Thalamic arterial group.

Computed tomographic (CT) manifestations of cerebral infarction along the distribution of the basal perforating arteries were reviewed and correlated with cerebral angiography. Infarcts in the territories of perforators were demonstrated individually based on knowledge of their three-dimensional distribution as shown by microangiography of cadavers. In Part II of the study, the posterior areas supplied by the thalamic arteries were examined. Infarcts in the area supplied by the thalamotuberal arteries involved the anterior pole of the thalamus; those in the area of the thalamoperforate arteries involved the medial portion of the thalamus, along the lateral wall of the third ventricle; those in the area of the thalamogeniculate arteries involved the posterolateral portion of the thalamus; and those in the area of the choroidal arteries of the lateral ventricle involved the most posterolateral and dorsolateral portions of the thalamus. Clinical and neuroradiological correlations are discussed.

Arteries↗
PubMed1983

Middle fossa arachnoid cyst: clinical, neuroradiological, and surgical features.

16 patients and 4 adult cases of small-or medium-sized middle fossa arachnoid cyst were subjected to various neuroradiological investigations and their results were analyzed in terms of possible mechanisms of cyst expansion. Based on the results of the investigations which strongly suggested that the cyst is an expanding lesion, all cases were surgically treated by the same techniques of craniotomy, excision of the outer cyst membrane, followed by a cystoperitoneal shunt, resulting in complete disappearance of the cyst concomitant with reexpansion of the surrounding brain and marked improvement in the clinical pictures of the patients.

Adolescent↗