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Biomedical subjects

K Kanemaru

Publications and source records attributed to K Kanemaru.

At least 37 records · Page 2Linked to original sources
PubMed1993

Expression of cathepsin G-like and alpha 1-antichymotrypsin-like proteins in reactive astrocytes.

The central nervous system (CNS) of many different species responds to diverse neurologic injuries with an activation of astrocytes. Yet, the exact function of this reactive astrocytosis is unknown. In this report, mouse astrocytes were activated in vivo by focal penetrating brain injury. Reactive astrocytes were stained with antibodies raised against the serine protease cathepsin G (cat.G), the serine protease inhibitor alpha 1-antichymotrypsin (ACT), or the astrocytic marker glial fibrillary acidic protein (GFAP). Reactive astrocytes expressing both cat.G-like and ACT-like antigens were found around cerebral wound margins between 18 h and 13 days after neural lesions. The injury-induced immunostaining was unaltered by 900 rads of total body irradiation, suggesting that the astroglial reaction was relatively independent of bone marrow-derived cells. The in vivo immunostaining was complemented with biochemical assays on cultured primary astrocytes. A synthetic peptide was used as a substrate in combination with specific inhibitors to identify a proteolytic activity within astroglial lysates and culture supernatants that closely resembles cat.G. This activity increased substantially upon stimulation of astrocytes with dibutyryl cyclic AMP and was neutralized by antibodies raised against cat.G. In a separate report, it was shown that astrocytes also contain an ACT-like inhibitory activity. The production of ACT- and cat.G-like antigens and activities by activated astrocytes should allow these cells to participate in a number of important biologic processes. Many of these processes may benefit the CNS by assisting in early wound repair. However, astroglial proteases and their inhibitors could also contribute to the pathogenesis of certain neurologic diseases.

Amino Acid Sequence↗
PubMed1992

Fetal-type phosphorylation of the tau in paired helical filaments.

To determine the phosphorylation sites of the tau in paired helical filaments (PHF), two types of PHF antisera with different specificities were used: One was a conventional anti-PHF, and the other was an antiserum to formic acid-denatured PHF (anti-HFoPHF). Phosphorylated tau-specific antibodies, anti-ptau 1 and anti-ptau 2, were prepared from anti-PHF and anti-HFoPHF, respectively. We found that both anti-ptau 1 and anti-ptau 2 labeled fetal or juvenile tau but not adult tau. The anti-ptau 1- and anti-ptau 2-recognition sites were immunochemically localized to the fragment Asp313 to Ile328 in the most COOH-terminal portion of tau. Furthermore, Ser315 was determined as the anti-ptau 2 recognition site. The sequence surrounding Ser315 was not found in the canonical sequences phosphorylated with known kinases.

Amino Acid Sequence↗
PubMed1991

[Computerized tomography immediately after surgery in the neurosurgical operating theater].

A TCT-300 scanner (manufactured by the Toshiba Co., Tokyo) has been installed in the operating room of Shinshu University Hospital since 1986. This neurosurgical operating CT scanner system was developed for obtaining intra- and postoperative CT images in the operating room. We have carried out immediate postoperative CT scanning in 206 cases: 170 were major and 36 were minor operations. A mobile CT scanner gantry has been used in 125 cases since June, 1988. We obtained CT images immediately after surgery on the digitalized operating table, the motion of which can be controlled as with the conventional CT scanner table. Immediate postoperative CT scans showed the extent of removed tumors or hematomas, position of the tip of ventricular or cisternal tubes, injury to the surrounding normal brain caused during the removal of lesions, and postoperative complications such as hemorrhage, brain swelling and surgical patties which had been inadvertently left in the wound. This CT scanner system in the operating room proved to be useful in the postoperative care of neurosurgical patients.

Adult↗
PubMed1990

Characteristic changes between core and peripheral surface temperature related with postanesthetic shivering following surgical operations.

The relationship between changes in the core and the surface temperature and postanesthetic shivering was studied in 100 patients who underwent general anesthesia. Patients were classified into four groups by the patterns of change in the core and peripheral surface temperature. Type II and type IV groups of patients showed a decrease in surface temperature during the major operation such as gastrectomy and radical mastectomy. Type I and type III groups of patients showed no lowered peripheral surface temperature and with low temperature difference between core and surface temperature during the operation. The patients in type II and IV groups showed increased difference between core and surface temperature. The postanesthetic shivering occurred at significantly higher rate compared to the other two groups. As possible reasons of the shivering, operation of long duration and insufficient circulating blood volume were considered. Shivering reduces the temperature difference in the thermoregulatory homeostasis. However, in patients in type I and III, the rate of shivering was low. Evaluation of the difference between core and peripheral surface temperature may be important to manage body temperature at a steady level during the operation. The monitoring of body temperature difference between core and peripheral surface during the operation may be useful for predicting to occurrence of postanesthetic shivering.

Journal Article↗
PubMed1990

Digitally controlled neurosurgical operating table--technical note.

The authors describe a new, digitally controlled operating table for neurosurgery. The apparatus includes a digitally controlled motor for manipulating the table and a rotary encoder with a central processing unit, which calculates and displays the table's position. The table can be operated with any type of digitalized computer system and its position is monitored by the encoder unit in real time.

Neurosurgery↗
PubMed1990

The presence of a novel protein in calf serum that recognizes beta amyloid in the formalin-fixed section.

Here we report on a monoclonal antibody, H6-33, that labels various beta-amyloid plaques, including diffuse plaques in the formalin-fixed, paraffin-embedded section from the brain affected with Alzheimer's disease (AD), without formic acid pretreatment. H6-33 also labels some neurofibrillary tangles and all kuru plaques in Gerstmann-Sträussler-Scheinker disease. In sharp contrast, H6-33 did not stain beta amyloid in the leptomeningeal vessel. For specific staining, H6-33 required the presence of fetal calf serum and it was necessary for beta amyloid to be formalin fixed. These results suggest that a novel protein in the calf serum, CSX, binds formalin-fixed beta amyloid, followed by H6-33 binding. The detection of beta amyloid by CSX was nullified by formic acid pretreatment of the tissue section. In accordance with this, CSX reacted only with a polymer form of synthetic beta peptide after fixation, but not with native beta-protein or beta-peptide monomer. These observations strongly suggest that 1) meningovascular beta amyloid should have a beta-pleated sheet structure somewhat dissimilar to that of beta-amyloid cores; and 2) most, if not all, of beta-protein immunoreactivities of diffuse plaques in AD sections are presumably derived from small amounts of amyloid fibrils scattered in the normal-looking neurohil.

Alzheimer Disease↗
PubMed1988

The Marfan syndrome with an XYY chromosome pattern.

A 36-year-old man who was diagnosed to have the Marfan syndrome with an XYY chromosome pattern is reported. He was tall with long limbs and arachnodactylia, and had severe aortic regurgitation (AR). The chromosome pattern studied in specimens of blood and bone marrow revealed an XYY chromosome pattern. The relationship between the Marfan syndrome and an XYY chromosome pattern is discussed.

Adult↗
PubMed1987

Subacute leucoencephalopathy induced by carmofur, a 5-fluorouracil derivative.

Three cases of leucoencephalopathy induced by carmofur (1-hexylcarbamoyl-5-fluorouracil), an antineoplastic derivative of 5-fluorouracil are reported and the literature is reviewed. Initial symptoms were unsteady gait and dementia developing several weeks or months after carmofur had been started. Symptoms increased gradually even after stopping the drug. Severe encephalopathy with confusion, delirium or coma appeared frequently. Symptoms were usually reversible but death occasionally occurred. The EEG showed marked slowing. Computed tomography of the brains of severely intoxicated patients showed marked hypodensity of the entire cerebral white matter. Carmofur must be discontinued immediately if any psychomotor symptoms develop.

Aged↗
PubMed1983

Anastomosis of the superior thyroid artery to the vertebral artery for vertebrobasilar insufficiency.

Anastomosis of the superior thyroid artery to the cervical vertebral artery was performed with good results in a case of vertebrobasilar insufficiency caused by proximal occlusion of the vertebral artery. As a donor artery the superior thyroid artery is moderate in size, long, and easy to anastomose. It is emphasized that this cervical procedure is simpler and safer than the intracranial procedures. The authors believe this case to be the first in which the superior thyroid artery was used as a donor artery for anastomosis to the vertebral artery.

Arteriosclerosis↗
PubMedDate not supplied

Synthesis and secretion of active alpha 1-antichymotrypsin by murine primary astrocytes.

Activated astrocytes have been identified as the main source of the serine protease inhibitor alpha 1-antichymotrypsin (ACT), an acute phase protein that is tightly associated with amyloid plaques in Alzheimer's disease (AD) and in normal aged human and monkey brain. We analyzed the synthesis of ACT by cultured murine astrocytes in vitro. The murine astrocytes expressed an ACT-like antigen that crossreacted with antibodies to human ACT. The murine ACT-like protein is secreted by the astrocytes and is able to form an SDS-resistant complex with the serine protease cathepsin G, indicating that the secreted ACT is biologically active. We conclude that cultured primary astrocytes synthesize and secrete murine ACT in an active form. We, therefore, suggest that the ACT present within AD plaques is locally derived from plaque-associated activated astrocytes as a part of a glia-mediated local inflammatory response that is associated with the neurodegeneration seen in AD.

Animals↗