Search PubMed⌕ Search

Biomedical subjects

Y Yoshioka

Publications and source records attributed to Y Yoshioka.

At least 73 records · Page 4Linked to original sources
PubMed1995

Characteristics of cytotoxic T lymphocytes directed to influenza virus haemagglutinin elicited by immunization with muramyldipeptide-influenza liposome vaccine.

We examined the characterization of the antiviral T lymphocytes elicited by immunization with a novel liposome vaccine (MDP-virosome) constructed with synthetic muramyldipeptide; [6-0-(2-tetradecylhexadecanoyl)-N-acetylmuramyl-L-alanyl-D-isoglutamine] , cholesterol, influenza virus haemagglutinin and neuraminidase. The haemagglutinin glycoprotein first appeared to induce a significant subtype-specific cytotoxic activity through its arrangement on the inner and outer surfaces of the MDP-virosome. Splenocytes of BALB/c mice immunized with the virosome vaccine containing H3 haemagglutinin and N2 neuraminidase from human Hong Kong virus markedly lysed H3N2 virus-infected target cells, but not those infected with virus possessing a different subtype such as H1N1 surface antigens. Exposure of these splenic lymphocytes to virus antigen in vitro further enhanced their cytotoxic activity. The cytotoxic lymphocytes generated by the MDP-virosome vaccine expressed Thy 1 and CD4 antigens on their cell surface, and these activities were restricted by class II histocompatibility gene products. The marked reduction of pulmonary virus titres in infected mice caused by transferred immune spleen cells suggested that the MDP-virosome vaccination is able to protect against influenza virus infection through enhanced cellular immune responses.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1995

[A case of cranial metastasis of hepatocellular carcinoma].

A case of cranial metastasis of hepatocellular carcinoma is reported. A 77-year-old woman with an elastic hard tumor in the right temporal region was referred to our department on April 30, 1992. On admission, the patient had slight weakness of the left upper limb. Plain skull X-ray and computed tomography (CT) showed bone destruction in the right temporal region. Magnetic resonance images (MRI) showed that the tumor was hypo-intense with T1-sequences and hyper-intense with T2-sequences, and included hyper-intense spots on both T1- and T2-images. Right carotid angiography showed that the tumor was fed by the middle meningeal and accessory meningeal arteries. The patient became disoriented, and the left hemiparesis worsened on May 4, 1992. CT scan revealed an irregular high-density area in the tumor because of intratumoral hemorrhage. After embolization of the arteries feeding the tumor, surgery was performed on May 8, 1992, and the tumor was totally removed. Histological examination of the tumor specimen revealed that it was a metastatic hepatocellular carcinoma. The patient died 8 months after initial diagnosis because of hepatocellular carcinoma.

Aged↗
PubMed1995

[Clinico-pathological studies on three preoperative combined treatments for rectal cancer].

To prevent postoperative local recurrence of rectal cancer, we treated patients using preoperative hyperthermia (5-6 times), irradiation (total 30 Gy) and 5-fluorouracil suppository (2,000-2,500 mg). The subjects were 31 patients given combined treatments and 28 patients given surgery alone. The results were as follows: 1. Histologically, therapeutic effects were recognized in 80.6% of patients receiving combined treatments. 2. The mean distance from the adventitia to the site of cancer infiltration was 6.54 mm in the combined treatments group and 3.35 mm in the surgery alone group. The difference between the two was significant (p < 0.05). 3. The rate of local recurrence in the combined treatments group was less than that in the surgery alone group. 4. No systemic side effects nor severe complications were observed during hospitalization in the combined treatments group. 5. The survival rate of the combined treatments group was higher than that of the surgery alone group. It was considered that combined preoperative treatments for rectal cancer were beneficial to survival and local control.

Adult↗
PubMed1994

Origin and evolutionary pathways of the H1 hemagglutinin gene of avian, swine and human influenza viruses: cocirculation of two distinct lineages of swine virus.

The nucleotide sequences of the HA1 domain of the H1 hemagglutinin genes of A/duck/Hong Kong/36/76, A/duck/Hong Kong/196/77, A/sw/North Ireland/38, A/sw/Cambridge/39 and A/Yamagata/120/86 viruses were determined, and their evolutionary relationships were compared with those of previously sequenced hemagglutinin (H1) genes from avian, swine and human influenza viruses. A pairwise comparison of the nucleotide sequences revealed that the genes can be segregated into three groups, the avian, swine and human virus groups. With the exception of two swine strains isolated in the 1930s, a high degree of nucleotide sequence homology exists within the group. Two phylogenetic trees constructed from the substitutions at the synonymous site and the third codon position showed that the H1 hemagglutinin genes can be divided into three host-specific lineages. Examination of 21 hemagglutinin genes from the human and swine viruses revealed that two distinct lineages are present in the swine population. The swine strains, sw/North Ireland/38 and sw/Cambridge/39, are clearly on the human lineage, suggesting that they originate from a human A/WSN/33-like variant. However, the classic swine strain, sw/Iowa/15/30, and the contemporary human viruses are not direct descendants of the 1918 human pandemic strain, but did diverge from a common ancestral virus around 1905. Furthermore, previous to this the above mammalian viruses diverged from the lineage containing the avian viruses at about 1880.

Amino Acid Sequence↗
PubMed1994

Cardiac hemangiopericytoma growing in the left atrium.

A 49-year-old woman was seen because of exertional dyspnea. Two-dimensional echocardiography revealed the presence of a large mass in the left atrium. An urgent operation was performed because the tumor suddenly stuck in the mitral orifice. The lesion, which occupied the entire left atrium, was resected during cardiopulmonary bypass. Histologic analysis revealed malignant hemangiopericytoma.

Female↗
PubMed1994

[A case report of infant botulism without a history of honey ingestion].

A 66-day-old female with infant botulism is reported. She was admitted to our hospital with respiratory failure. Laboratory examinations detected botulinal toxin type A in her feces. This was the first case with no history of honey ingestion among the 13 cases of infant botulism reported in Japan. It is possible that other cases, in which honey had not been consumed, remain undiagnosed. Further studies may be needed to clarify the factors necessary to cause infant botulism.

Botulism↗
PubMed1994

[Usefulness of 5-FU high-dose continuous therapy at home in patients with recurrent gastric and colon cancer].

Recurrence of gastric cancer or colon cancer was observed in some patients who received 5-fluorouracil (5-FU) high-dose continuous Methotrexate (MTX)-Leucovorin (LV) therapy (FML therapy) previously. 5-FU high-dose 48-hours continuous therapy (5-FU therapy) as maintenance therapy for the patients was performed in the hospital and successively at home. The patients included 3 with recurrent gastric cancer and 2 with recurrent colon cancer: there were 4 males and 1 female, the mean age was 51.8 years (33-59 years). All patients had received FML therapy during the hospital stay before the maintenance chemotherapy at home. 5-FU therapy (30 mg/kg/day x 2 days/w), 30.2 courses on an average (11-40 courses), was performed through a catheter (Port-A-Cath), which was introduced into the right subclavian vein and placed under the skin, with a Baxter infusion pump. The concentration of 5-FU was 197 +/- 172-401 +/- 127 ng/ml between the 2nd and 48th hour. Adverse reaction included anorexia in 5 patients, stomatitis in 4, pigmentation in 4, leukopenia in 3, neuropathy in 2 and alopecia in 1. The therapy was effective for 10.4 months on an average (4-18 months) and the mean survival period was 12.0 months (7-18 months).

Adult↗
PubMed1994

[Surgical treatment of descending thoracic aortic aneurysm with simple aortic cross-clamping versus left heart bypass using centrifugal pump].

Surgical treatment has been employed in 52 patients (pts) with descending thoracic aortic aneurysm (DS-TAA). Based on the adjuncts during aneurysmal repair, the series is divided into 2 groups; simple aortic cross-clamping was utilized to manage the lesion in group SC (n = 42), while left heart bypass using a centrifugal pump was employed during the period of aortic occlusion in LHB group (n = 10). Of these 52 pts, 4 died in hospital (group SC:2, group LHB:2). The most common complication was the respiratory failure following the renal failure. No paraplegia occurred in both groups. Biochemistric measurements of alanine aminotransferase, creatinine (CRN) and amylase (AMY) showed no difference between group SC and group LHB. In pts of SC group with normal renal function, post-operative maximum (post Max) CRN during the first month had a logarithmic correlation with total aortic cross-clamp time (TAXT). The post Max CRN of LHB group with normal renal function remained less than 3.0 mg/dl even in the case with TAXT over 60 minutes. There is also a linear correlation of post Max AMY in pts of SC group. Late survival at 4 years, including hospital death, were 83% in SC group and 63% in LHB group. We conclude that DS-TAA cases with TAXT of less than 30 min with good distal organ function can be managed with simple aortic cross-clamping; otherwise usage of LHB was recommended to support distal circulation.

Adult↗
PubMed1993

Novel radioactive phospholipid probes as a tool for measurement of phospholipid translocation across biomembranes.

In an attempt to develop a new method to measure transbilayer phospholipid translocation, with a higher sensitivity and higher temporal resolution, novel radioactive phospholipid probes (*C5-PC, *C5-PE, and *C5-PS) with a short acyl chain at the 2-position were synthesized. The *C5-PC probe was made by coupling lysophosphatidylcholine with [14C]pentanoic acid, using N,N-carbonyldiimidazole as a coupling agent (yield 37%), and *C5-PE and *C5-PS were synthesized by exchanging the choline moiety of *C5-PC for ethanolamine and L-serine, respectively, as catalyzed by phospholipase D. The usefulness of the probes was confirmed by measuring phospholipid translocation across the human erythrocyte plasma membrane, in which the presence of aminophospholipid translocase was revealed using EPR techniques (Zachowski, A., Farve, E., Cribier, S., Herve, P. and Devaux, P.F. (1986) Biochemistry 25, 2585-2590). Using the present probes, ATP-dependent and SH-reagent-inhibitable translocation of *C5-PS and *C5-PE from outer to inner leaflets, which is characteristic to the translocation mediated by aminophospholipid translocase, was detected with a higher sensitivity than seen with the EPR technique. These radioactive phospholipid probes will be useful to measure phospholipid translocation with a high sensitivity and have the potential for application in measurements of transbilayer lipid-translocation for a wide variety of membranes.

Biological Transport↗
PubMed1993

Molecular characterization of a short interspersed repetitive element from tobacco that exhibits sequence homology to specific tRNAs.

We have characterized a family of tRNA-derived short interspersed repetitive elements (SINEs) in the tobacco genome. Members of this family of SINEs, designated TS, have a composite structure and include a region structurally similar to a rabbit tRNA(Lys), a tRNA-unrelated region, and a TTG repeat of variable length at the 3' end. Southern blot hybridization, together with a search of the GenBank data base, showed that various plants belonging to the families Solanaceae and Convolvulaceae contain sequences homologous to the TS family in the introns and flanking regions of many genes, whereas Arabidopsis in the family Cruciferae and several species of monocoytledonous plants do not. The TS family is widely involved in structural and genetic variations in the genomes of many plants that belong to the order Tubiflorae. All of nine sequences identified in a data base search are truncated at their 5' regions and lack the tRNA-related region of the TS family. We characterized the entire sequence of the members of the TS family and found that this family can be categorized as a member of a group of SINEs with a tRNA(Lys)-like structure, as can several animal SINEs. The TS family can be divided into two major subfamilies by analysis of diagnostic positions, and one of the subfamilies is clearly younger than the other. Amplification of many copies of the full sequence of the younger subfamily occurred during the recent evolution of the tobacco lineage. We also discuss mechanisms that could be involved in the generation of SINEs in animals and also in plants.

Base Sequence↗
PubMed1993

In vitro characterization of lung cancers by the use of 1H nuclear magnetic resonance spectroscopy of tissue extracts and discriminant factor analysis.

Using proton magnetic resonance spectroscopy (1H MRS) spectra were obtained in vitro from extracts of four types of lung cancer (squamous cell, adenocarcinoma, large cell, small cell) and normal lung. The hydrophilic phase of the chloroform/methanol-water extracts yielded several distinct peaks. Among them the peak areas for cholines, creatines, glycine, and alanine, and their ratios were calculated and used as parameters to characterize different lung tissues. The ratios, cholines/alanine and glycine/alanine, were significantly (P < 0.001 to P < 0.05) higher for the normal lung than lung cancers. Creatines/glycine and creatines/cholines generally provided good discrimination (P < 0.001 to P < 0.05) between any two types of lung cancer. When data were further analyzed by discriminant factor analysis, there was 81.5 to 90.7% accuracy in predicting between normal lung and each cancer type, or among the four types of lung cancer. These results suggested that 1H MRS might be useful as an adjunct modality in the differential diagnosis of lung cancers.

Adenocarcinoma↗
PubMed1993

Evaluation of left ventricular function utilizing transesophageal echocardiography during and after thoracic aortic aneurysm repair.

This study was designed to evaluate left ventricular (LV) function during aortic cross-clamping (ACC) by comparing left heart bypass (LHB) with a centrifugal pump and simple aortic cross-clamping (SC). The end-diastolic volume index (EDVI), ejection fraction (EF), fractional shortening (FS) and end-systolic meridional stress (ESS) were measured by transesophageal echocardiography. The measurements were performed 1) before ACC, 2) 2 min after ACC, 3) 20 min after ACC, 4) 2 min after unclamping and 5) 1 h after unclamping. With cross-clamping, a significant decrease was observed in both EDVI (108 vs 83 ml/m2) and EF (73 vs 67%) in patients with LHB. Patients utilizing SC showed a sustained increase in ESS (43 vs 64 10(3) dyne/cm2). The systolic blood pressure did not vary during LHB, but a transient increase occurred in patients with SC. With release of the cross-clamping, EDV and EF returned to the baseline values in patients with LHB. A significant decrease occurred in EDVI (101 vs 71 ml/m2) and ESS (61 vs 36 10(3) dyne/cm2) in the SC group. We conclude that circulatory support with LHB may offer greater stability of the LV function during thoracic aortic cross-clamping than SC because of the lower preload and afterload.

Aged↗
PubMed1993

[Study on human diseased thyroid cells in collagen gel culture--morphology and their malignancy of cultured colonies].

Thyroid cells from 14 normal subjects, two patients with Grave's disease, four patients with follicular adenoma and eight patients with papillary carcinoma were cultured in collagen gel. The colonies of these cells were stereoscopically observed and their morphological characteristics were studied with regard to relation with pathological findings of mother tumor, extra-capsular invasion and metastatic potential. For normal thyroid, Grave's disease and follicular adenoma (except for one case), their own characteristic branching type colonies were found. For papillary carcinoma, both branching type and spheroid type of colonies were observed. The ratio of branching type/spheroid type varied individually in the patients with papillary carcinoma. However, the spheroid type was found to trend to be predominant in patients with extra-capsular invasion and/or lymph node metastasis. This means that the observation of spheroid type colonies in collagen gel is suggestive of risk of extra-capsular invasion or lymph node metastasis. From the obtained results, it seemed possible to diagnose poorly-differentiated cells in vitro by morphologically observing colonies of human thyroid papillary carcinoma cells developing in collagen gel.

Adenoma↗
PubMed1993

[Activities of antibiotics against methicillin-resistant Staphylococcus aureus with particular reference to synergetic effect between ticarcillin and fosfomycin on penicillinase non-producing methicillin-resistant S. aureus].

We tested susceptibilities of 46 strains of clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) to arbekacin (ABK), tobramycin (TOB), ticarcillin (TIPC), clavulanic acid/ticarcillin (CVA/TIPC) and fosfomycin (FOM). Twelve strains had penicillinase activity. Most strains were resistant to TOB, TIPC, FOM and CVA/TIPC, but ABK inhibited 80% of the 46 MRSA strains at a concentration of 1.56 microgram/ml. The combination of ABK and FOM was indifferent. Synergism was observed, however, between FOM and TIPC against 79% of penicillinase non-producing MRSA. This synergism may mean that FOM inhibits the production of penicillin-binding protein 2' in some strains of penicillinase non-producing MRSA.

Bacterial Proteins↗
PubMed1993

[Newly-developed catheter for cardio-renal assist during intraaortic balloon counterpulsation].

A new catheter was developed for the cardio-renal assist during intra-aortic balloon counterpulsation. The catheter consists of both a large balloon of conventional IAB (TMP balloon) located at the distal end of the catheter and an additional small balloon 10 cm distant from the large balloon with common lumen and single shaft. Experimental study was carried out in the mock circulatory system simulating the descending aorta employing a conventional IAB catheter as a control. It was demonstrated that the flow in the mid portion between both balloons could be increased maximally by as much as 28% of that of the control under the continuous flow and 214% under the pulsatile flow. The double balloon catheter was considered to improve the renal perfusion as well as the coronary perfusion.

Assisted Circulation↗
PubMed1993

[A case of T-cell type malignant lymphoma of the lung].

A case of T-cell type malignant lymphoma of the lung was reported. A 69-year-old woman was referred to our institute because of an abnormal shadow on the chest roentgenogram. She was symptom-free, and physical examination showed no abnormalities. Her laboratory tests were within normal limits. The chest roentgenogram showed a well-defined, nodular density in the left lower lung field without air bronchogram. She underwent a left lower lobectomy and a mediastinal lymphnodes dissection. This disclosed an elastic hard nodule, 2 cm in diameter, without pleural invasion. Pathologically the tumor was diagnosed as malignant lymphoma of T-cell type without regional lymphnode involvement. She is doing well without any sings of recurrence for one year after the operation.

Aged↗
PubMed1993

Morphological properties of human thyroid tumor cells in collagen gel culture and metastatic or invasive ability.

Using normal human thyroid cells and tumor cells, the reconstruction of various diseased cells in collagen gel as well as the relationship between the morphology of colonies in collagen-embedded culture and the biological behavior (benignity, malignancy, metastasis, and invasion) of the original tumors were studied. In collagen gel culture, normal thyroid cells reorganized follicle-like constructions, and follicular adenoma cells showed in vivo-like constructions. However, two different types of colonies were observed in cultures of cells from papillary carcinomas. One was the branching type with many outgrowths projecting to three dimensions and the other was the spherical type without any outgrowths. These spherical colonies were observed in all cases of papillary carcinoma, but varied from one case to another. Metastasis and invasion were detected during pathological examination in cases with a high ratio of spherical colonies. Our results indicate that cells from highly metastatic and invasive thyroid cancer form spherical colonies in the collagen gel culture, and that this collagen culture is a useful method for studying the heterogeneity of tumor cells as well as the metastasis and invasive ability of tumor cells in vitro.

Adenoma↗