Biomedical subjects

A Hayashi

Publications and source records attributed to A Hayashi.

At least 145 records · Page 8Linked to original sources

PubMed1998

Helicobacter pylori infection in the remnant stomach after gastrectomy: with special reference to the difference between Billroth I and II anastomoses.

Helicobacter pylori infection is associated with many gastric diseases, such as peptic ulcer and gastric cancer. We examined the remnant stomach for H. pylori infection after gastrectomy for gastric cancer or peptic ulcer between October 1992 and July 1997. H. pylori DNA in the gastric juice of 109 patients [mean age 62.4 years, male/female 78/31, gastrectomy for gastric cancer 83/peptic ulcer 26, Billroth I (BI) anastomosis 72/Billroth II (BII) 37, mean postoperative interval 6.0 years] was amplified by PCR and detected by Southern blot hybridization. The serum of 135 patients was assayed by ELISA for IgG antibody against H. pylori (mean age 61.8 years, male/female 99/36, gastrectomy for gastric cancer 111/peptic ulcer 24, BI anastomosis 93/BII 42, mean postoperative interval 5.4 years). H. pylori was positive in 68/109 (62.4%) by PCR and 113/ 135 (83.7%) by ELISA. H. pylori cytotoxin gene cagA, a H. pylori virulence factor gene, was found in 15/16 (93.8%) cases by PCR. A significant difference in H. pylori positivity by PCR was found according to the type of anastomosis (BI vs. BII) but not according to age group, sex, disease (cancer or ulcer), or postoperative interval by PCR and ELISA. BII anastomosis was followed by a significantly lower rate of H. pylori infection (17/37; 45.9%) than BI anastomosis (51/72; 70.8%; p=0.01) according to the results of PCR. Moreover, some patients with BII anastomosis (3/8; 37.5%) showed positive to negative seroconversion for H. pylori infection after the operation (mean 2.47 years) according to the results of ELISA, but this phenomenon was not observed in patients with BI (0/12) anastomosis. This may reflect the role of bile reflux, which is more common in BII than BI, because bile reflux interferes with colonization by H. pylori.

Adult↗

PubMed1998

Low-dose irradiation induces expression of heat shock protein 70 mRNA and thermo- and radio-resistance in myeloid leukemia cell line.

We examined the effects of in vitro low-dose irradiation on myeloid leukemia cells (M1 cells) and found that it enhanced the colony-forming ability (CFA) of M1 cells in semi-solid agar. This enhancement was inhibited by treatment with a protein synthesis inhibitor, cycloheximide and with an RNA synthesis inhibitor, actinomycin D, after irradiation. These findings suggested that low-dose irradiation induced the synthesis of some proteins which were attributed to the enhancement of CFA. Since we expected that one species of these proteins were heat shock proteins (hsps), we attempted to detect the hsp70 family by the Western blotting method and inducible hsp70 mRNA by the RT-PCR method. Low-dose irradiation induced the expression of hsp70 mRNA, whereas the enhancement of hsp70 (an inducible isoform) and hsc70 (a constitutively expressed isoform) expression could not be found. Furthermore, the M1 cells showed thermoresistance 1 h after low-dose pre-irradiation, and also showed radioresistance 4 h after irradiation. This time difference after pre-irradiation might be attributed to the different species of proteins in showing resistance to lethal stress. Therefore, some proteins other than hsp70 were believed to be concerned with the augmentation of CFA and the induction of thermo- and radio-resistance.

Animals↗

PubMed1998

Effectiveness of polyclonal and monoclonal antibodies prepared for an immunoassay of the etofenprox insecticide.

Two polyclonal antibodies and three monoclonal antibodies specific to the etofenprox insecticide were prepared from rabbits and mice, respectively. The monoclonal antibodies were more reactive with etofenprox than the polyclonal antibodies by C-ELISA. Monoclonal antibody cl 205-65 was found to be the most tolerant to methanol, most highly reactive and most specific to etofenprox among the antibodies tested.

Animals↗

PubMed1998

Experimental study of the histocompatibility of covered expandable metallic stents in the trachea.

STUDY OBJECTIVES: To evaluate the histocompatibility of four different materials used to cover expandable metallic stents. DESIGN: Prospective, randomized, unblinded study. SETTING: Animal research laboratory of Kurume University. PATIENTS OR PARTICIPANTS: Twenty 12- to 18-kg mongrel dogs. INTERVENTIONS: Handmade Gianturco-type stents with six bends, 20 mm in length, and 15 to 20 mm in diameter were covered using four different materials: polypropylene mesh, silicone-coated mesh, polyester mesh, and ePTFE. Covered stents were inserted into the trachea after i.v. anesthesia. Five animals were used in each group. MEASUREMENTS AND RESULTS: Postinsertion status was observed using clinical and bronchoscopy measures 7, 14, 28, and 56 days after intervention. Eight weeks after stent insertion, the tracheal specimens were studied pathologically. A scoring system was used to evaluate the histocompatibility of covered stents in each study group. The mean of clinical scores in the polypropylene group was 1.84+/-0.36, which was significantly higher than those in the groups of silicone, polyester, and ePTFE. The means of histopathologic scores in the polypropylene group and the silicone group were 1.60+/-0.55, which were significantly higher than those in groups of polyester and ePTFE. CONCLUSIONS: Polypropylene mesh cover was more suitable than silicone-coated mesh, polyester mesh, and ePTFE because of its excellent histocompatibility.

Anesthesia, Intravenous↗

PubMed1998

Tuberculosis associated with pulmonary sequestration.

We describe a case of intralober pulmonary sequestration in association with tuberculosis. Sequestrations of the lung are classically divided into two types of extralober and intralober. Intralober pulmonary sequestration in association with tuberculosis is rare. We diagnosed the present case to be Pryce type 1 with tuberculosis infection.

Bronchopulmonary Sequestration↗

PubMed1998

Foveal translocation: a comparison of two techniques.

Subfoveal choroidal neovascular membrane is a leading cause of legal blindness. Photocoagulation has been effective, but photocoagulation of the fovea causes a decrease in vision immediately after treatment. Surgical removal of the choroidal neovascular membrane is effective for choroidal neovascular membrane in some cases, but it restores useful vision for reading (20/40 or better) in a small number of cases of choroidal neovascular membrane not due to presumed ocular histoplasmosis syndrome. A new treatment for subfoveal choroidal neovascular membrane, foveal translocation, is an innovative procedure in which the fovea is translocated onto healthier retinal pigment epithelium. Three techniques have been developed to relocate the retina, 2 of which (retinotomy and scleral shortening) we performed in 5 cases each. Preliminary results in these 10 cases indicate that foveal translocation provides improvement of visual acuity in 40% of eyes and final visual acuities useful for reading (better than 20/40) in 20% of eyes undergoing translocation with either technique. Further study is essential to refine the amount of translocation needed and to decrease complications of the 2 techniques, including retinal detachment, proliferative vitreoretinopathy, macular pucker, corneal astigmatism, and constricted visual field.

Adult↗

PubMed1998

Study on Parkinson's disease and alcohol drinking.

To clarify alcohol drinking habits of patients with Parkinson's disease (PD) in Japanese, we compared mean values of alcohol consumption of PD patients and controls with special references to genetic polymorphism of ALDH2. Ninety-three Japanese outpatients with PD (39 males, 54 females) diagnosed by three skilled neurologists from 4 hospitals in Kanto area were analyzed for ALDH2 genotypes and alcohol consumption. A total of 297 healthy controls (156 males, 141 females) in the same area were also analyzed. PCR- SSCP (polymerase chain reaction-single strand conformational change polymorphism) analysis was used to determine ALDH2 genotypes. Mean values of alcohol consumption (ethanol g/month/person) from patients with PD were estimated by direct interview, and those from controls were obtained by questionnaire. Distributions of three genotypes and allele frequencies of ALDH2 were not different between patients and controls, however mean values of alcohol consumption of PD group were significantly lower than those of control group when compared between the same ALDH2 genotype. Our data suggested that the lower values of alcohol consumption in patients with PD for every ALDH2 genotypes may be caused by other factors such as premorbid personality rather than ALDH2 variant.

Aged↗

PubMed1998

[Method and evaluation of experimental retinal reattachment].

An animal model of retinal reattachment is needed to study experimental macular relocation and recovery of reattached retina. The purpose of this study was to develop and evaluate a simple technique of retinal reattachment. We used the right eye of 13 pigmented rabbits for this experiment. 3 weeks before the operation, the eyes underwent a gas induced vitreous compression with sulfur hexafluoride gas. Transcleral subretinal hydrodissecction was used to create a partial (60-70% of the whole retina) retinal detachment. Retinal reattachment was observed in ten eyes 18 hours after the operation. The dark-adapted electroretinograms (ERGs) were recorded in 3 rabbits from 3 days to 3 months after the surgery. Selected eyes were enucleated for histology. The amplitude of ERGs (a-wave and b-wave) were reduced to 30% and 40% of the control eyes on day 3. These waves were restored up to 70% and 80% of normal at 2 weeks and showed no significant changes thereafter. Degeneration and loss of photoreceptors in the early days after surgery as seen by light microscopy were almost completely restored to normal at 3 months after surgery. This model provides large retinal detachment and reattachment with minimized inflammatory response.

Animals↗

PubMed1998

[A case of livedo vasculitis associated with mononeuritis multiplex].

Livedo vasculitis is characterized by recurrent livedo reticularis of lower extremities and the histopathological findings of segmental hyalinizing vasculitis in the skin. We report a case of a 26-year-old female who manifested mononeuritis multiplex 7 years after the onset of livedo vasculitis. She showed sensori-motor disturbances in the right median and ulnar nerves and sensory deficits of the bilateral peroneal nerves. Sural nerve biopsy revealed a remarkable loss of large and small myelinated fibers and a few vasculitic changes. Steroids therapy was effective for these neurological symptoms. But paroxysmal numbness appeared later recurrently in the regions of affected nerves with painful ulcerations in the right leg. Laboratory tests indicated increased levels of serum thrombin-antithrombin complex (TAT), and antithrombotic drugs (argatroban) remarkably ameliorated the recurrent symptoms and skin lesions. These findings suggest that the pathogenesis of livedo vasculitis might be related to alterations of the blood coagulation system.

Adult↗

PubMed1998

[A case of hypertrophic cranial pachymeningitis associated with intramedullary lesion developed seizure marching from right lower extremity].

A case of hypertrophic cranial pachymeningitis associated with intramedullary lesion was reported. A 57-year-old male presented with the symptoms of Jacksonian seizure and weakness of right lower extremity. Neurological examination showed weakness and muscular atrophy of right lower extremity (MMT 1-2) and hyperreflexia. Superficial sensation and position sense were normal, however cortical sensory disturbance was recognized in his right lower extremity. MRI revealed diffuse dural thickening with gadolinium enhancement in the left convexity and hyperintense lesion in the bilateral (left dominant) frontal to parietal lobe on T2 weighted image. Magnetic resonance angiography (MRA) and digital subtraction angiography (DSA) showed occlusion of the superior sagittal sinus. Histological examination revealed extensive fibrous tissue with lymphocytes infiltration around the vessels. The cause of the intramedullary lesion in this patient may have been related to the occlusion of superior sagittal sinus, due to thickening dura mater and influence of inflammation.

Angiography, Digital Subtraction↗

PubMed1998

[A case of marginal zone B-cell lymphoma].

A 60-year-old woman had an abnormal shadow in the right lower lung field on chest roentgenogram. Transbronchial lung biopsy revealed findings consistent with malignant lymphoma, and a right middle lobectomy was performed. Pathological findings showed that tumor cells had infiltrated the epithelium, forming so-called lymphoepithelial lesions. Flow cytometric analysis of the resected specimen revealed that B-cell associated antigens (CD 19, 20) were expressed, and that the tumor cells were CD 5-, CD 10-. A marked increase in the number of lymphocytes with an IgM kappa component suggested monoclonal origin for the tumor cells in the resected specimen. Southern blot analysis showed clonal rearrangement of the heavy chain of the immunoglobulin gene. A diagnosis of malignant lymphoma of bronchus-associated lymphoid tissue was made. This tumor was defined according to the revised European. American classification of lymphoid neoplasms as a marginal zone B-cell lymphoma.

Antigens, CD19↗

PubMed1998

Enzyme immunoassay of urinary mevalonic acid and its clinical application.

We have developed an enzyme immunoassay for mevalonic acid (MVA), using a specific monoclonal antibody. The intra- and interassay coefficients of variation calculated on two urine samples were 3.3% and 3.4%, respectively, in the intraassay precision test and 3.5% and 6.9% in the interassay evaluation. Pravastatin, a 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor, was administered to nine healthy men, and in all cases, their MVA excretion rates then decreased. The more MVA that was excreted in the urine before the pravastatin administration, the greater a reduction of MVA excretion was observed. The daily MVA excretions in healthy men (n = 120) and women (n = 105) were 2.32 micromol/day (SD, 0.82 micromol/day) and 1.85 micromol/day (SD, 0.47 micromol/day), respectively. In streptozotocin-induced diabetic rats (n = 14), the plasma cholesterol concentrations and MVA excretion rates were increased, and a positive correlation was observed between the plasma cholesterol and the urinary MVA concentrations.

Adult↗

PubMed1998

Primary hemangiopericytoma of the superior mediastinum: a case report.

We present a case of hemangiopericytoma arising in the superior mediastinum. A 48-year-old man demonstrated a superior mediastinal mass lesion on chest x-ray and was admitted to our hospital. A CT scan of the chest showed a well-circumscribed, heterogenously-enhanced mass, 7.0 x 6.5 x 6.5 cm in size, located in the right superior posterior mediastinum, compressing the trachea. The tumor was extirpated by surgical resection. Based on the histological findings, electron microscopic findings, and immunohistochemical studies, the tumor was diagnosed as hemangiopericytoma.

Diagnosis, Differential↗

PubMed1998

[A case report of steroid-responsive progressive encephalomyelitis with rigidity showing muscle stiffness limited to the upper body].

A 37-year-old female presented with progressive encephalomyelitis with rigidity for a period of about three months. Spasms began with several minutes of paroxysmal painful muscle stiffness in the left upper limb, followed by pain and muscle spasms in the upper limbs, shoulders, neck and back. The paroxysmal painful spasms were easily evoked by light touches and startling. The patient had contracture in the upper limbs and difficulty in relaxing the muscles. She also developed brain stem signs such as left sixth nerve palsy. The serum antinuclear antibody was positive (1 : 160). The cerebrospinal fluid examination revealed mild pleocytosis and protein elevation. Brainstem MRI, cervical MRI, and electroencephalography were normal. Surface electromyography in the arm and neck muscles showed continuous motor unit discharge elicited by passive movement of the right arm. Diazepam and baclofen were minimally beneficial. After treatment with intravenous injection of high-dose methylprednisolone and sequential oral prednisolone administration, the patient showed substantial improvement. This disorder may be part of a clinical spectrum that has an underlying autoimmune basis.

Administration, Oral↗

PubMed1998

Natriuretic peptides in the lung modulated by pneumonectomy.

BACKGROUND: Natriuretic peptides are vasodilator hormones involved in the regulation of blood pressure and volume homeostasis. However, the mechanism of these peptides after pneumonectomy remains obscure. METHODS: We investigated changes in the pulmonary arterial pressure and the localization and changes in the atrial (A-type) natriuretic peptide (ANP) and the C-type natriuretic peptide (CNP) in the lung, using immunohistochemistry and radioimmunoassay (RIA) in anesthetized dogs. Furthermore, we examined guanosine 3', 5'-monophosphate (cGMP) levels in plasma and in the contralateral lung. RESULTS: Pulmonary arterial pressure was significantly increased after pneumonectomy. The immunoreactivities of both ANP and CNP were detected in the endothelium of the pulmonary artery. In the contralateral lung, the concentrations of ANP and CNP were both significantly increased. In plasma, only ANP levels were significantly increased. In contrast, the plasma and lung cGMP levels were significantly reduced after pneumonectomy. CONCLUSIONS: We postulate that the processes from secretion in the vascular endothelial cells to the action via ANP and CNP receptors are effected in the contralateral lung tissue at the acute stage of pneumonectomy.

Animals↗

PubMed1998

Thoracoscopic resection of a giant leiomyoma of the esophagus with a mediastinal outgrowth.

We reported a case of a 20-year-old man with a giant leiomyoma of the esophagus resected under video-assisted thoracic surgery (VATS). The patient demonstrated an abnormal shadow on a chest x-ray and a posterior mediastinal tumor 11 cm in diameter on a computed tomogram (CT) and on magnetic resonance imaging (MRI). A leiomyoma or a neurogenic tumor of the esophagus was suspected, and VATS was performed. The resected tumor was pathologically confirmed to be a leiomyoma of the esophagus. A giant esophageal leiomyoma showing extraluminal outgrowth should be treated by VATS.

Adult↗

PubMed1997

Positively charged liposome functions as an efficient immunoadjuvant in inducing immune responses to soluble proteins.

To design an optimum liposome immunoadjuvant for soluble protein antigens, we investigated the relationship between liposomal surface charge and adjuvant action. Positively charged multilamellar vesicles (MLV) were taken up efficiently by macrophages, while negatively charged and neutral MLVs were hardly picked up. Consistent with this, positively charged MLVs containing soluble chicken egg albumin (OVA) functioned as a more potent inducer of antigen-specific cytotoxic T lymphocyte (CTL) responses and antibody production than negatively charged and neutral MLVs containing the same concentrations of antigens. These results indicate that the positive charge on the surface of liposomes represents an important factor for enhancing their immunoadjuvancy in the induction of antigen-specific immune responses.

Adjuvants, Immunologic↗

PubMed1997

Comparative gene mapping of the human and mouse TEP1 genes, which encode one protein component of telomerases.

The chromosomal locations of the human TEP1 (telomerase protein component 1) and mouse Tep1 genes, which were originally named TLP1 (telomerase protein 1) or TP1 (telomerase-associated protein 1), were determined by direct R-banding FISH and a molecular linkage analysis with interspecific backcross mice. The human TEP1 and mouse Tep1 genes were mapped by FISH to human chromosome 14q11.2 and to the C2D1 band of mouse chromosome 14, respectively. By means of genetic linkage mapping, the mouse gene was further localized as being 2.7 cM distal to D14Mit18 and D14Mit134 and 2.0 cM proximal to D14Mit5 on mouse chromosome 14, where conserved linkage homology with human chromosome 14q11-q12 has been identified.

Animals↗