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Biomedical subjects

T Aoki

Publications and source records attributed to T Aoki.

At least 289 records · Page 16Linked to original sources
PubMed1999

Keratin subunit expression in human cultured melanocytes and mouse neural crest cells without formation of filamentous structures.

The synthesis of keratin is considered to occur in epithelial and epidermal cells. Previous studies have not reported on keratin synthesis within melanocytes that derive from neural crest cells. Epithelial and neural crest cells originally develop from ectodermal tissue. We previously reported that the expression of keratin is a universal phenomenon seen in cultured melanoma cell lines, as demonstrated by two-dimensional polyacrylamide gel electrophoresis, western blot, and electron microscopy analyses. To further investigate the specificity of keratin function in melanocytic cells, we first examined the presence of keratin proteins in cultured human melanocytes, and unexpectedly found keratin subunits in melanocytes by the above-mentioned procedures. The keratin (K) subunits were composed of K1, K5, K8, K10, K14, K16, and K18, together with vimentin. Neural crest cells, which contain immature embryonic melanocytes developing from ectoderm, already expressed keratins; however, under electron microscopy, the expressed keratin did not form filamentous structures. Although the ATP synthase alpha-chain, which is expressed universally in cultured epidermal tumor cell lines, was also expressed in cultured melanocytes and neural crest cells, a novel malignant melanoma-related protein (MMRP) was absent in melanocytes and neural crest cells. We concluded that keratin subunits are present in both cells, but do not construct keratin filaments.

Animals↗
PubMed1999

Primary synovial sarcoma of the lung: report of two cases confirmed by molecular detection of SYT-SSX fusion gene transcripts.

AIMS: Primary pulmonary sarcoma is rare, and frequently creates diagnostic challenges. We describe two cases of primary pulmonary spindle cell sarcoma in which a molecular approach using archival paraffin-embedded tissue was proved to aid diagnosis. METHODS AND RESULTS: Both patients had huge masses replacing the upper and middle lobes of the lung, respectively, without any primary extrapulmonary neoplastic lesions. Microscopically, the lesions showed a solid hypercellular nodular or lobular growth of atypical short spindle cells in variably intersecting fascicles or in a haphazard fashion, together with focal areas displaying a prominent haemangiopericytoma-like pattern. Immunohistochemically, a small number of the tumour cells were positive for epithelial markers such as cytokeratin and epithelial membrane antigen. In both cases, a reverse transcription-polymerase chain reaction using RNA extracted from formalin-fixed, paraffin-embedded tissues detected SYT-SSX fusion gene transcripts, which are characteristic of synovial sarcoma. CONCLUSION: On the basis of the morphological and molecular findings, these tumours are considered to be rare examples of monophasic synovial sarcoma of the lung. Our molecular assay detecting the SYT-SSX fusion transcripts is useful for the final diagnosis of synovial sarcoma arising at such an unusual anatomical site.

Adult↗
PubMed1999

Comorbidity of depression among physically ill patients and its effect on the length of hospital stay.

This study was carried out to demonstrate the prevalence of depression among physically ill patients and to investigate its effects on the length of hospital stay. Out of 65 inpatients (44 male, 21 female; 51 with benign and 14 with malignant diseases), 14 (21.5%) met the criteria for major depression in the DSM-IV. The average length of hospital stay was compared according to the comorbidity with major depression. Among the patients with benign diseases, those with major depression stayed longer (P<0.05) at the hospital than those without it (82.2 vs. 36.0 days). Likewise, among the cancer patients, those with major depression stayed longer than those without it (83.8 vs. 51.4 days), although this was not significantly different. The duration of hospitalization needs to be shortened because of the reduction in national medical costs, the economics of hospital administration and the quality of life of patients and their families. Further research is needed to demonstrate the role of consultation-liaison psychiatry in the shortening of hospitalization.

Adult↗
PubMed1999

General hospital psychiatry from the perspective of medical economics.

The purpose of this study was to investigate the efficacy of consultation-liaison (C-L) psychiatry from the perspective of medical economics, by comparing a part-time and full-time psychiatric department. One full-time (5 days per week) psychiatrist began work at a general hospital (GH-A), and one part-time (once per week) psychiatrist had been working at another general hospital (GH-B). Both general hospitals are teaching hospitals of the same size. The number of patients and the medical reimbursements were investigated each month and compared. This study demonstrated that the establishment of C-L psychiatry was economically profitable in contrast with what was the common belief among general hospital administrators. Also, the differences in the total number of patients (GH-A: GH-B = 500:35-50 patients/month) and the total reimbursement (GH-A: GH-B = 3 million: 2-300000 yen/month) was not explained by the number of working days (GH-A: GH-B = 5:1 day/week). The full-time model of C-L psychiatry has also indirect effects (i.e. educational and relieving effects) on the hospital staff. Promoting the establishment of C-L psychiatry requires many evidence-based studies that demonstrate the necessity for C-L psychiatry and can directly persuade hospital directors.

Cost-Benefit Analysis↗
PubMed1999

Primary amebic meningoencephalitis due to Naegleria fowleri: an autopsy case in Japan.

Free-living amebas represented by Naegleria fowleri, Acanthamoeba and Balamutia have been known to cause fatal meningoencephalitis since Fowler and Carter (1965) reported the first four human cases. An autopsy case of a 25-year-old female with primary amebic meningoencephalitis (PAM) due to Naegleria fowleri is described. Headache, lethargy and coma developed in this patient, and her condition progressed to death 8 days after the onset of clinical symptoms. Cerebral spinal fluid examination confirmed clusters of amebas, which were grown in culture and identified as Naegleria fowleri. At autopsy, lesions were seen in the central nervous system (CNS) and the ethmoid sinus. The CNS had severe, suppurative meningoencephalitis with amebic trophozoites mingled with macrophages. This case is the first report of PAM due to Naegleria fowleri in Japan.

Adult↗
PubMed1999

Molecular analysis and diagnosis in Japanese patients with Wilson's disease.

BACKGROUND: Wilson's disease is characterized by the toxic accumulation of copper in the liver, brain, cornea and other organs. It is caused by both impaired excretion via the bile and impaired incorporation of copper into ceruloplasmin in the liver. The Wilson's disease gene (ATP7B) has been cloned as a putative copper-transporting P-type ATPase gene. We therefore analysed mutations of ATP7B in Japanese patients with Wilson's disease. METHODS: Twenty-three Japanese patients with Wilson's disease were investigated. In all patients, the ATP7B coding sequence, including exon-intron junctions, was analysed by restriction endonuclease digestion, mutation detected enhancement gel electrophoresis and/or direct sequencing analysis of amplified fragments. RESULTS: Thirteen mutations were identified, including seven missense mutations, four detections, one insertion and one exon skipping in the coding region. The most common mutations were 2874deletion(del)C in exon 13 and arginine (Arg)778 leucine (Leu) in exon 8. DISCUSSION: None of the observed mutations, except for 2302insertion(ins)C, have been previously detected in either European or North American patients. We conclude that the mutation spectrum of Wilson's disease may thus indicate a population-dependent pattern. Based on the population-dependent manner of the occurrence of ATP7B gene mutations, it may be possible to establish a molecular diagnosis system. A molecular diagnosis system is considered to be very effective for making a definitive diagnosis in very young patients and for also detecting carriers.

Adenosine Triphosphatases↗
PubMed1999

Treatment and management of Wilson's disease.

Wilson's disease is an autosomal recessive disorder related to the copper metabolism. The clinical symptoms are due to copper deposition in various tissues, including liver, brain, kidney, cornea and others. The key strategy of treatment is to reduce the amount of copper in the liver and other tissues by administering both copper-chelating agents and a low copper diet. D-Penicillamine is considered to be the first choice as a copper-chelating agent. Patients require 15-25 mg/kg daily in the early stages of treatment and this drug should also be given more than 2 h before meals. Some undesirable or serious side-effects, such as systemic lupus erythematosus (SLE) and nephrotic syndrome, do occur in 20-25% of all patients. In such cases, trienthylene tetramine (trientine) appears to be as effective as penicillamine. This drug is usually used when D-penicillamine has to be withdrawn. It is also sometimes administered to patients with neurological symptoms as a first-choice drug. It is given in doses of 40-50 mg/kg daily, in the same manner as for D-penicillamine. Zinc salt administration has also emerged as an interesting supportive therapy for both treatments. A dose of 5-7.5 mg/kg daily is given before meals. The copper content of the diet should be less than 1 mg/day in the early stages of treatment. Thereafter, it can be increased to 1.0-1.5 mg/day during well-controlled periods. Liver transplantation is now performed in many countries for patients with either the fulminant or chronic progressive types of Wilson's disease.

Chelating Agents↗
PubMed1999

Mass screening for Wilson's disease: results and recommendations.

Wilson's disease is a treatable inherited disorder of copper metabolism. Established treatments include the use of oral chelating agents and the establishment of a minimum copper diet, although prognosis mainly depends on the extent of liver or nervous system damage present before treatment. Once irreversible damage has occurred, the effect of these treatments is diminished and the patient's quality of life compromised. Therefore, the establishment of a mass screening system able to detect Wilson's disease patients presymptomatically has been discussed. Recently, a monoclonal antibody specific to holoceruloplasmin has been developed. This antibody was used in a nationwide screening trial of 126,810 newborn infants, but no Wilson's disease patients were identified. However, three patients out of 24,165 were diagnosed with Wilson's disease using this specific antibody in a screening performed during the period from late infancy to elementary school. The age of 3 years is thought to be the best point for Wilson's disease mass screening. In this paper, a review of mass screening for Wilson's disease in Japan using a specific monoclonal antibody to holoceruloplasmin is presented.

Antibodies, Monoclonal↗
PubMed1999

Developmental profile of prolactin cells in the anterior pituitary of postnatal rats during the lactational stage.

Changes in prolactin (PRL)-, growth hormone (GH)- and PRL/GH-containing cells in the anterior pituitary of pre- and postnatal male and female rats were determined using immunocytochemistry with double fluorescent antibodies. The pituitary glands from a fetus on Day 20 of gestation and pups on Days 0, 1, 4, 7, 12, and 20 of the postnatal period with sex distinction were monodispersed and subjected to immunocytochemistry. Following immunostaining, the three types of cells described above were counted (i.e., only PRL-, only GH-, and both PRL and GH-positive cells in a visual field of microscope). Anterior pituitaries and blood were obtained from pups on Days 0, 1, 4, 7, 12, and 20 after birth and pooled with sex distinction, and bioactive PRL levels in the anterior pituitary and serum were measured using an Nb2 rat lymphoma cell bioassay. Double fluorescent-labeled immunocytochemistry was able to distinguish reliably between PRL-, GH-, and PRL/GH-containing cells. The PRL cells increased rapidly after parturition to 4 days of age and after 12 days of age in both genders. The latter increase was involved in the remarkable increase of PRL/GH-containing cells, which were first found at term and remained at low levels until 12 days of age. The weight and PRL level of the anterior pituitary increased in both sexes throughout the lactational stage, but the levels in female rats at 20 days of age were significantly greater than those of male rats. Serum PRL concentration remained at low levels except on Day 0. The present results demonstrate that the development of PRL-containing cells in postnatal rats during the lactational period is activated with two distinct stages, at term to Day 4 and after Day 12, and the development in the latter stage is involved with sexual dimorphism.

Age Factors↗
PubMed1999

Postoperative delirium and plasma melatonin.

The molecular mechanisms of postoperative delirium are not understood in detail yet. This condition is similar to cases of mental symptoms in interferon therapy or hemodialysis. We propose that postoperative delirium is caused by a deficiency of serotonin, an important neurotransmitter, and review the evidence supporting our hypothesis. The serotonin deficiency results from a decrease in tryptophan, the serotonin precursor, and from an increase in melatonin, a serotonin metabolite. Our hypothesis may be applicable to the mechanisms of mental symptoms in interferon therapy and hemodialysis. In addition, we discuss to the relationship between homeostasis and biorhythms because postoperative delirium may be a dysrhythmia.

Delirium↗
PubMed1999

Abdominal aortic aneurysmectomy with left-sided inferior vena cava and transplanted kidney.

Aortic aneurysmectomy was performed in a 43-year-old man with left-sided inferior vena cava (It-IVC) after renal transplantation 10 years before. In the admission examination chronic rejection was found histopathologically. For renal protection, a temporary heparin-coated shunt tube was used to maintain continuous blood flow to the transplanted kidney. The shunt was placed between the left brachial artery and the right external iliac artery, because there was no segment healthy enough for cannulation of the shunt tube and the It-IVC crossed over the aorta above the aneurysm. Aortic aneurysmectomy was performed without complications and perioperative renal function was satisfactorily maintained without progression of the chronic rejection.

Adult↗
PubMed1999

Respiratory insufficiency caused by an aneurysm with multiple vascular lesions.

A 71-year-old woman, who presented tracheobronchial obstruction caused by a thoracic aortic aneurysm, was admitted to our institution. Although she had multiple cerebral infarctions, old myocardial infarction, bilateral iliofemoral atherosclerotic lesions with abdominal aortic aneurysm, and superior vena cava syndrome, aneurysmectomy was undertaken in order to rescue her from respiratory insufficiency. The operation successfully relieved her of exertional dyspnea and dysphagia.

Aged↗
PubMed1999

A surgical management of aortic insufficiency concomitant with mediastinal well-differentiated liposarcoma.

We present a rare case of a mediastinal liposarcoma concomitant with aortic insufficiency due to myxoid degeneration of the aortic valve. Because the patient's left ventricle was in moderate dilatation and a posterolateral thoracotomy combined with median sternotomy was required in order to perform a complete resection of a mediastinal liposarcoma, it was decided to carry out aortic valve surgery and tumor excision in one operation.

Aortic Valve Insufficiency↗
PubMed1999

Establishment of surgically induced chronic acid reflux esophagitis in rats.

BACKGROUND: The purpose of the study was to establish an animal model of chronic acid reflux esophagitis which could be used for further investigations of the pathophysiology of reflux esophagitis. METHODS: Esophagitis was produced by ligating the transitional region between the forestomach and the glandular portion with a 2-0 silk thread and covering the duodenum near the pylorus ring with a small piece of an 18Fr Nélaton catheter. The histologic features of the esophagus were examined, and the survival rate of these animals was investigated. Moreover, the effects of lansoprazole on this model was studied. RESULTS: The 3-week survival rate was 90%, and esophagitis was noted in all rats. Esophagitis was found 2 or 3 cm above the esophagogastric junction in most cases and at 4.0+/-2.3 sites per animal. Histopathologically, there were increased thickness of the esophageal epithelium, elongation of the lamina propria papillae, which extended upward into the epithelium, marked inflammatory cell infiltration, interruption of the lamina muscularis mucosae, and increase of collagen fibers in the lamina propria and submucosa. These signs were in accord with the histologic features of typical chronic esophagitis. No signs of esophagitis were observed, except in one animal, in the rats given 1 mg/kg/day of lansoprazole. CONCLUSIONS: This experimental rat model is considered useful as a model of chronic acid-type esophagitis for the evaluation of the pathophysiology of reflux esophagitis and the evaluation of drug efficacy.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1999

Alteration of perceived fragrance of essential oils in relation to type of work: a simple screening test for efficacy of aroma.

The perceptional change of fragrance of essential oils is described in relation to type of work, i.e. mental work, physical work and hearing environmental (natural) sounds. The essential oils examined in this study were ylang ylang, orange, geranium, cypress, bergamot, spearmint and juniper. In evaluating change in perception of a given aroma, a sensory test was employed in which the perception of fragrance was assessed by 13 contrasting pairs of adjectives. Scores were recorded after inhaling a fragrance before and after each type of work, and the statistical significance of the change of score for 13 impression descriptors was examined by Student's t-test for each type of work. It was confirmed that inhalation of essential oil caused a different subjective perception of fragrance depending on the type of work. For example, inhalation of cypress after physical work produced a much more favorable impression than before work, in contrast to orange, which produced an unfavorable impression after physical work when compared with that before work. For mental work, inhalation of juniper seemed to create a favorable impression after work, whereas geranium and orange both produced an unfavorable impression then. From these studies, together with those conducted previously with lavender, rosemary, linalool, peppermint, marjoram, cardamom, sandalwood, basil and lime, we thus concluded that the sensory test described here might serve not only as a screening test for efficacy of aroma but also as a categorized table for aroma samples which can act as a reference to each other.

Adult↗
PubMed1999

Induction of CD8+ T cell-mediated protective immunity against Trypanosoma cruzi.

Trypanosoma cruzi was transformed with the Plasmodium yoelii gene encoding the circum-sporozoite (CS) protein, which contains the well-characterized CD8+ T cell epitope, SYVPSAEQI. In vivo and in vitro assays indicated that cells infected with the transformed T. cruzi could process and present this malaria parasite-derived class I MHC-restricted epitope. Immunization of mice with recombinant influenza and vaccinia viruses expressing the SYVPSAEQI epitope induced a large number of specific CD8+ T cells that strongly suppressed parasitemia and conferred complete protection against the acute T. cruzi lethal infection. CD8+ T cells mediated this immunity as indicated by the unrelenting parasitemia and high mortality observed in immunized mice treated with anti-CD8 antibody. This study demonstrated, for the first time, that vaccination of mice with vectors designed to induce CD8+ T cells is effective against T. cruzi infection.

Animals↗
PubMed1999

Molecular cloning and biochemical characterization of a novel cytochrome P450, flavone synthase II, that catalyzes direct conversion of flavanones to flavones.

Cytochrome P450 cDNAs, AFNS2 and TFNS5, were isolated from snapdragon and torenia petal cDNA libraries, respectively, based on the sequence homology with licorice CYP93B1 cDNA encoding (2S)-flavanone 2-hydroxylase. They were expressed in yeast and identified to encode flavone synthase II catalyzing direct conversion of flavanones to flavones probably via 2-hydroxyflavanones.

Amino Acid Sequence↗