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Biomedical subjects

Y Morisawa

Publications and source records attributed to Y Morisawa.

At least 19 recordsLinked to original sources
PubMed1999

Regeneration process of mechanoreceptors in the reconstructed anterior cruciate ligament.

We performed reconstructive surgery on the anterior cruciate ligament (ACL) of the rabbit using a free bone-patellar tendon-bone (BTB) graft and evaluated nerve regeneration in the graft. The right ACL of 15 Japanese white rabbits was resected and reconstructed using a BTB graft. The BTB and ACL from the contralateral knee served as controls. The graft and control BTB were collected at 2, 4, and 8 weeks after the operation. We measured the number of mechanoreceptors in the ligaments using a modified gold chloride method. In the control patellar tendon, mechanoreceptors were present in all the samples. At 2 weeks after the operation, mechanoreceptors were not observed in the reconstructed ligaments. They were observed at 4 weeks but in lower numbers than in the control knees. At 8 weeks, the total number of mechanoreceptors did not differ significantly in the reconstructed and control tendons. The appearance of mechanoreceptors in the graft between 2 and 4 weeks postoperatively suggests that regeneration of mechanoreceptors occurred during this time period. At 4 and 8 weeks postoperatively, there was no significant difference in the number of mechanoreceptors between the intra-articular portion of grafted tendon and the contralateral ACL. The further increase between 4 and 8 weeks to control levels suggests that this regeneration may restore mechanoreceptors in BTB grafts to normal levels.

Animals↗
PubMed1999

A study of mechanoreceptors in fibrocartilage masses in the defect of pars interarticularis.

We investigated the origin of low back pain associated with lumbar spondylolysis and spondylolytic spondylolisthesis by removing fibrocartilage masses from the lytic sites in symptomatic patients and staining the masses by the Gairns gold chloride method to examine mechanoreceptors. The fibrocartilage masses were found to contain four types of mechanoreceptors: Pacinian corpuscles, Ruffini receptors, Golgi tendon organ-like receptors, and free nerve endings. All of these mechanoreceptors were present at the periphery of the specimens, and Ruffini receptors and free nerve endings were abundant. Some mechanoreceptors had a slightly atypical structure, in addition to those with typical morphology. Comparison with mechanoreceptors in normal lumbar facet joint capsules showed that there were more mechanoreceptors in the fibrocartilage masses and a greater proportion of atypical structures at lytic sites. The presence of mechanoreceptors at lytic sites suggests that the fibrocartilage masses are not simply scar tissue filling the defect. Rather, these masses also appear to play a protective role by sensing instability via mechanoreceptors and transmitting this information as pain, while at the same time acting as ligament-like tissue that connects and stabilizes the separated vertebral arches.

Adolescent↗
PubMed1999

Coronary artery bypass grafting in a patient with human immunodeficiency virus: role of perioperative active anti-retroviral therapy.

In a patient with severe ischemic heart disease and advanced human immunodeficiency virus (HIV) infection, vigorous perioperative treatment with anti-retroviral agents was given and coronary artery bypass surgery using cardiopulmonary bypass was successfully performed. This strategy could become the standard for patients with cardiovascular disease and advanced HIV infection. The following aspects of this case require further investigation: (1) lack of a reactive increase in the neutrophil count, (2) transient extreme reduction of lymphocytes, and (3) a relative decrease in the CD8+ cell ratio.

Acquired Immunodeficiency Syndrome↗
PubMed1999

[Smallpox].

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Diagnosis, Differential↗
PubMed1999

[Varicella].

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Adult↗
PubMed1998

Lysosomal glycogen storage disease with normal acid maltase with early fatal outcome.

In a male infant who had cardiomyopathy, generalized muscle weakness and increased serum creatine kinase levels, his muscle biopsy revealed myopathic changes with tiny intracytoplasmic vacuoles containing PAS-positive material and high acid phosphatase activity, but had normal acid maltase activity biochemically. These findings were consistent with those seen in lysosomal glycogen storage disease with normal acid maltase (Danon disease). Sarcolemmal indentations commonly seen in this disease were missing, but a complement membrane attack complex, C5b-9 was positive along the surface membrane of the muscle fibers as seen in X-linked vacuolar myopathy. The patient was on a respirator and died at 27 months of age from pneumonia and hypertrophic cardiomyopathy. Lysosomal glycogen storage disease with normal acid maltase may be manifested at birth with marked skeletal and cardiac involvement leading to death in early infancy.

Biomarkers↗
PubMed1998

Morphological study of mechanoreceptors on the coracoacromial ligament.

We performed gold chloride staining of coracoacromial ligaments removed at operation, observed the peripheral nerve endings in the ligament, and studied their distribution and changes with aging in order to clarify the proprioception of the shoulder joint. The coracoacromial ligament was found to contain four types of typical nerve endings: Pacinian corpuscles, Ruffini receptors, Golgi tendon organ-like receptors, and free nerve endings. In addition, non-typical Pacinian corpuscles and Ruffini receptors with non-typical morphology were present. There were also unclassifiable nerve endings with a morphology which did not fit any of the above categories. These typical, non-typical, and unclassifiable nerve endings were all widely distributed on the surface of the subacromial side at the insertion into the acromion and around the coracoid process in the ligament. Free nerve endings were found sporadically on the surface of the subacromial bursal side in the ligament. The resected coracoacromial ligaments (23 specimens) were divided into two groups based on the disorder that required surgery: a fracture group without subacromial impingement (5 specimens) and a group with subacromial impingement (18 specimens). Age-related changes in the number of nerve endings were compared in each group. The total number of nerve endings decreased with age in both groups. The number of Pacinian corpuscles, Ruffini receptors, Golgi tendon organ-like receptors, and free nerve endings of typical morphology tended to decrease with age. The data from the fracture and subacromial impingement groups were not analyzed statistically because of the difference in the number of specimens in each group. However, the total number of nerve endings was lower in the subacromial impingement group than in the fracture group at all ages. The typical nerve endings of the coracoacromial ligament in both groups tended to decrease in the elderly, suggesting that the proprioception of the shoulder joint may become impaired with aging.

Acromioclavicular Joint↗
PubMed1998

Antimicrobial effects of electrolytic products of sodium chloride--comparative evaluation with sodium hypochlorite solution and efficacy in handwashing.

We examined the in vitro bactericidal effects and efficacy on handwashing of water containing electrolytic products of sodium chloride (electrolytic water). The electrolytic water, whose pH and concentration of free residual chlorine were 6.7-6.9 and 20-22 ppm, respectively, showed equal reduction of both Staphylococcus aureus and Escherichia coli to dilution of commercially available sodium hypochlorite containing 60 ppm of free residual chlorine. This bactericidal effect was calculated to be due to hypochlorous acid, based on the pH and the amount of chlorine in solution. Handwashing with the electrolytic water reduced the numbers of S. aureus on hands by 1/10(2), while running water and 0.2% benzalkonium chloride with 80% ethanol gave a 1/10 and 1/10(5) reduction, respectively. We conclude that electrolytic water might be applicable for handwashing in place of running water.

Chlorine↗
PubMed1997

Mechanoreceptors of patellar tendon used for ACL reconstruction. Rabbit experiments.

In 17 Japanese white rabbits (weighing 2.6-3.7 kg), the anterior cruciate ligament of the right knee was resected and then reconstructed, using the lateral half of the patellar tendon. The contralateral side served as control. Rabbits were killed 10, 20, or 30 weeks postoperatively. Then the reconstructed ligament was harvested and stained, using a modified gold chloride method. Under the light microscope, sensory nerve endings in serial sections were counted after being morphologically identified. With respect to the number of Pacinian and Ruffini corpuscles, there were no significant differences between the reconstructed ligament and the control patellar tendon at any time after surgery.

Animals↗
PubMed1994

[Clinical studies on cefozopran in pediatrics].

We conducted clinical studies on cefozopran (CZOP), a newly developed parenteral cephalosporin, for its clinical application in the field of pediatrics. 1. A clinical study was performed on 16 children with infections, including 9 with pneumonia, 1 each with acute bronchitis, enterocolitis, purulent lymphadenitis, 4 with skin and soft tissue infections. CZOP was administered by 30 minutes intravenous drip infusion. Doses varying from 20 to 35 mg/kg body weight were given t.i.d. Lengths of treatment ranged from 4 to 14 days. 2. Clinical efficacies were excellent in 10 and good in 6 cases, with an efficacy rate of 100%. The overall bacterial eradication rate for the pathogenic bacteria was also 100%. 3. Side effect was noted in 1 case with skin rash. Abnormal laboratory test data were found in 5 cases including slight elevations of GPT in 4 cases and GOT in 2 cases.

Adolescent↗
PubMed1993

Synthesis and anthelmintic activity of 13-alkoxymilbemycin derivatives.

The synthesis of milbemycin derivatives having alkyloxy groups at the C-13 position was studied and a series of these analogs of milbemycin A4 and A3 was prepared by the reaction of 13-iodomilbemycin with a variety of alcohols. 13 beta-Phenethyloxy derivatives were found to possess excellent anthelmintic activity. Especially, the activities of derivatives with N-substituted 4-aminophenethyloxy groups were comparable to or superior to ivermectin against Nippostrongylus brasiliensis in rats.

Animals↗
PubMed1993

[Clinical studies of S-1108 fine granules in pediatrics].

We have evaluated S-1108 fine granules for therapeutic effectiveness in children. The results are summarized as follows. 1. A clinical study was performed with 16 children with infections, including 8 with acute tonsillitis, 3 with acute pharyngitis, 2 with scarlet fever, 1 each with acute bronchitis, pertussis and urinary tract infection. Doses ranging from 8.8 to 10.6 mg/kg body weights were given in 3 divided portions. Durations of treatment ranged from 2 to 15 days. The therapeutic responses were considered "excellent" in 1 and "good" in 13, with an efficacy rate of 87.5%, and the bacteriological eradication rate was 91%. 2. No adverse reactions were observed. In laboratory tests, eosinophilia was observed in one patient. It was concluded the S-1108 was promising drug for the treatment of bacterial infections in children.

Administration, Oral↗
PubMed1992

Synthesis and biological action of the aminotetrahydroisoquinocarbazoles and related compounds: a new class of compounds with antiarrhythmic activity.

A series of 12-aminotetrahydroisoquinocarbazoles and related compounds were synthesized using an intramolecular Diels-Alder reaction and screened for antiarrhythmic activity in chloroform-induced ventricular arrhythmias in mice. Several compounds showed more potent activity than disopyramide. There was some correlation between substituents on aromatic ring and angular position, and antiarrhythmic activity. An amino group or some functional groups containing an amino group on C-12 seemed to be essential to exhibit the activity. Ring size also influenced the activity. The compound (+)-10 (RS-2135) had the most favorable combination of antiarrhythmic activity and toxicity and was selected for further evaluation.

Action Potentials↗
PubMed1991

Protection of mice from lethal endotoxemia by use of an ornithine-containing lipid or a serine-containing lipid.

The effects of an ornithine-containing lipid [alpha-N-(3-acyloxyacyl)-ornithine (Orn-L)] or a serine-containing lipid [alpha-N-(3-acyloxyacyl)-serine (Ser-L)] from Flavobacterium meningosepticum on lethal endotoxemia in mice were examined. When 500 micrograms of Orn-L was intravenously administered 1 h before intravenous administration of a lethal dose of endotoxin, none of the mice died. The protective effect of Ser-L was weaker than that of Orn-L. Light and electron microscopic studies demonstrated that necrosis of hepatocytes caused by endotoxin was prevented by pretreatment with Orn-L. Furthermore, Kupffer cells were activated morphologically 1 h after the administration of Orn-L or Ser-L, and the liposomes of the lipoamino acids were incorporated into phagolysosomes in activated Kupffer cells. The activity of tumor necrosis factor in sera of endotoxin-treated mice was decreased markedly by pretreatment of mice with Orn-L. In vitro, the lipoamino acids suppressed endotoxin-induced tumor necrosis factor generation but did not suppress tumor necrosis factor generation induced by zymosan and whole cells of Staphylococcus aureus. These results suggested that Orn-L and Ser-L can be used as specific blocking agents against endotoxin. The blocking mechanism may be antagonistic, because of the structural similarities between the lipoamino acids and endotoxin lipid A.

Animals↗
PubMed1991

[A cohort study on deaths from SMON in Japan].

Causes and risk factors of deaths from subacute myelo-optico neuropathy (SMON) were studied in a prospective cohort of 4,329 SMON patients followed for 3 years and 7 months (Sept. 1985-March 1989) with the following findings: (1) Recent excess deaths of SMON patients was estimated as 4% from ratio of O/E (SMR = 104) and deaths due to SMON itself was 6.4%. (2) The ratio of O/E was significantly higher for deaths from cancer of colon/rectum in females, cancer of pancreas in males, hypertension in males, pneumonia/influenza in females, chronic obstructive pulmonary diseases in males, tuberculosis and intestinal obstructive disease in males and females. (3) The ratio of O/E was 1.8 times or greater for those SMON patients with complications of cerebrovascular disease, severe blindness, complete loss of ambulation, and who were bedridden, and who are unable to receive home care from family members or trained home helpers.

Cause of Death↗