Search PubMed⌕ Search

Biomedical subjects

Y Kojima

Publications and source records attributed to Y Kojima.

At least 109 records · Page 6Linked to original sources
PubMed2000

[Evaluation of antiretroviral chemotherapy based on the profile of virus isolation from HIV-1 infected individuals].

It is well-known that the biological characteristics of HIV-1 persistently infected in the host have often changed into a rapid growth in vitro, T-cell line tropism and marked syncytium inducing (SI) ability accompanied by the progress of clinical stages from AC to ARC or AIDS. We have developed a follow-up diagnostic test using the clinical markers based on the virus phenotypes mentioned above, and reported that the test was significantly useful for determining the clinical status of HIV infected individuals. Recently, highly active antiretroviral therapy (HAART) was introduced into HIV-1 chemotherapy, and has been reported to be a markedly effective treatment for HIV infected individuals. In this study, we carried out an investigation to see whether the follow-up diagnosis was useful even after introducing the HAART in Japan in 1997. The results by the laboratory diagnosis on 139 HIV infected individuals who were clinically observed over a long period showed that the positive rate of virus isolation and MT-4 cell tropism in the isolates during the two years between 1997 and 1998 were significantly lower than that of the nine years from 1988 to 1996 before the implementation of HAART. In addition, we obtained data that the effect of HAART reflects the biological profiles of virus isolation more than the CD4+ T cell counts. These results suggest that data of clinical examination using virus isolation as a parameter are useful not only for predicting the development of AIDS but also for evaluating the effects of HAART, particularly in patients showing no association between the CD4+ T cell counts and the plasma viral load.

Acquired Immunodeficiency Syndrome↗
PubMed2000

HLA-DRB genotypes in Japanese patients with renal cell carcinoma.

OBJECTIVES: Several clinical features, such as the spontaneous regression of some renal cell carcinoma (RCC) metastases after nephrectomy, suggest immune involvement in tumor destruction. PATIENTS AND METHODS: We investigated the role of genetic variation at the HLA class II loci in RCC by analyzing the HLA-DR antigen and HLA-DRB1, DRB3, DRB4 and DRB5 alleles in 55 patients using the polymerase chain rection. RESULTS: No statistically significant differences were observed in the frequency of the HLA-DR antigen or HLA-DRB3, DRB4, or DRB5 genes between the patients and a healthy control group. On the other hand, the HLA-DRB1*0403 and *1202 alleles were significantly more frequent in the patients than in the controls (p < 0.001 and p < 0.01, respectively). CONCLUSION: RCC might be linked to these two alleles in Japanese patients.

Adult↗
PubMed2000

Transition zone biopsy in the detection of prostate cancer.

OBJECTIVE: About 25% of all prostate cancers occur in the transition zone (TZ). We analyzed the impact of 4 systematic TZ and 2 systematic apex (AP) biopsies in addition to systematic sextant biopsies in an effort to establish the diagnostic importance of early prostate cancer. METHODS: One hundred and thirty patients underwent systematic transperineal multipoint prostate biopsy (biopsy of 12 sites, including 4 TZ and 2 AP biopsies). RESULTS: Forty-one of 130 men (31.5%) had biopsy specimens positive for cancer, and cancer originated in the TZ alone in 4 of these 41 patients (9.8%). Fourteen patients underwent radical retropubic prostatectomy. We compare the pathological findings of radical prostatectomy specimens and biopsy results. Prostate cancers predicted to be stage T(2c) by TZ biopsy were all classified as pT(2c) or greater. CONCLUSIONS: Routine TZ biopsy does not substantially increase the prostate cancer detection rate; however, it can be useful in patients who require repeat biopsy.

Aged↗
PubMed2000

Inhibition of binding of E- and P-selectin to sialyl-Lewis X molecule suppresses the inflammatory response in hypersensitivity pneumonitis in mice.

The carbohydrate structure of sialyl-Lewis X (SLe(x)) can function as a ligand for E- and P-selectin, which play important roles in mediating the initial interactions of leukocytes with the endothelium in inflammatory responses. In this study we evaluated the effects of inhibiting E- and P-selectin function with the SLe(x) molecule on the inflammatory response in an experimental murine model of hypersensitivity pneumonitis (HP). Antigen exposure induced marked interstitial and especially perivascular and peribronchiolar infiltration with lymphocytes and granuloma formation, in murine lung sensitized with Saccaropolyspora rectivirgula. These pathologic changes were significantly suppressed with SLe(x) ganglioside analogues through a reduction in the numbers of lymphocytes in bronchoalveolar lavage fluid, as evidenced by the lung index and histologic scores indicating the severity of the inflammatory response. Using specific antibodies, we also evaluated the immunohistochemical localization of SLe(x) in mononuclear cells in granulomas, and of E- and P-selectin in vascular endothelium. Our findings suggest that the molecular interaction between SLe(x), and E- and P-selectin mediates lymphocyte recruitment into the lung parenchyma, which is critical for the inflammatory response in experimental murine models of HP.

Alveolitis, Extrinsic Allergic↗
PubMed2000

Identification of somatotrophs, mammosomatotrophs, and mammotrophs by sandwich cell immunoblot assay in GH-secreting adenomas and prolactinomas: correlations between the proportions of hormone secreting cells and tumor size.

Sandwich cell immunoblot assay(sandwich CIBA) was used to identify somatotrophs (GH cells), mammosomatotrophs, and mammotrophs (PRL cells) in pituitary tumors obtained from patients with GH-secreting adenomas and prolactinomas. The mean serum GH level was 177.6 ng/ml in 19 patients with GH-secreting adenomas and the mean PRL level was 2,129 ng/ml in 9 patients with prolactinomas. GH-secreting adenomas could be divided into 3 groups according to the proportions of the cell types. The GH cell dominant type had more than 70% GH cells. The mammosomatotroph cell dominant type had more than 80% mammosomatotrophs. The non-dominant type had no dominant cell type. There was a good correlation (r2=0.804) between serum GH levels and tumor size in patients with the GH cell dominant type (n=10). The nondominant type (n=8) had a low serum level of GH except for one tumor. The mammosomatotroph cell dominant type (n=1) showed high serum levels of both GH and PRL. All prolactinomas had a predominance of PRL cells. Sandwich CIBA is a simple method for detecting GH cells, mammosomatotrophs, and PRL cells, and useful for classification for GH-secreting adenomas.

Adenoma↗
PubMed2000

Effects of skin pressure by clothing on digestion and orocecal transit time of food.

In order to reveal the influence of clothing skin pressure on digestion of food through the gastrointestinal tract, we examined the absorption of dietary carbohydrate and orocecal transit time of a test meal by means of a breath hydrogen test on 7 healthy young women. In this experiment, we collected breath samples from the participants wearing loose-fitting experimental garment on the second day of the experiment and from the same participants but wearing an additional tight-fitting girdle on the following day for 16 hours and 9 hours, respectively. Skin pressure applied by a girdle on participant's waist, abdomen and hip region was 15.5 +/- 0.4 mmHg (mean +/- SE), 11.0 +/- 0.2 mmHg, and 13.6 +/- 0.6 mmHg, respectively, and the values were 2-3 times larger than those of the experimental garment. The hydrogen concentration vs. time curve showed that breath hydrogen levels at its peaks (15:00, 15:30, 16:00, 16:30, and 17:00 hr) on the third day of the experiment were significantly higher than those of the corresponding time on the second day (p < 0.05 at 17:00 and 15:00, p < 0.01 at 15:00, 16:00 and 16:30). Consequently, significantly pronounced breath hydrogen excretion was observed under the "pressure" clothing condition (p < 0.01). On the other hand, the transit time of the test meal for the subjects wearing a girdle did not differ significantly from that for the subjects wearing the garment of less pressure (270 +/- 18 minutes and 263 +/- 21 minutes, respectively). These results indicate that the clothing skin pressure has an inhibitory effect on the absorption of dietary carbohydrate in the small intestine, but no effect on the orocecal transit time of a meal.

Adult↗
PubMed2000

Everyday breath hydrogen excretion profile in Japanese young female students.

A breath hydrogen test has been used widely as a noninvasive and simple method of detecting carbohydrate malabsorption as well as estimation of the small intestinal and orocecal transit time. By means of this method, we have examined the change in breath hydrogen concentration of young female students in their everyday life in order to reveal the breath hydrogen excretion profile under normal circumstances. In this survey, we have asked them to collect their own breath samples every one-hour as regularly as possible during one day from awakening until bedtime. We also asked them to complete the questionnaire concerning their dietary habit, dietary record and physical activities. Among the 43 subjects who gave the breath hydrogen records, 37 subjects excreted detectable hydrogen into their alveolar air. By comparing the changes in breath hydrogen concentration during the time of day, breath hydrogen excretions could be classified into two distinct patterns; more than half of the total hydrogen excretion occurred in the first half of the waking hours (designated as "pattern A", 18 cases) and in the latter half (designated as "pattern B", 19 cases). Taking into consideration the subjects' records of diets and physical activities, the early-pronounced breath hydrogen excretion observed among 18 "pattern A" students was probably resulted from the malabsorption of the dietary carbohydrate in the breakfast meals.

Adult↗
PubMed2000

The tau and anti-tau effects in successively presented stimuli.

It was confirmed by the reproduction method with 20 adults that (a) the tau effect, i.e., the greater the temporal separation between successively presented stimuli with a constant spatial interval, the greater the apparent spatial interval, occurred, especially in the situation in which the participants were assumed to form a set easily using temporal interval as the cue for spatial interval estimation, and (b) the anti-tau effect occurred in the special situation in which the participants were assumed to form a set using speed of an imaginary movement as the cue for it. These findings supported the hypothesis of "cue-selection sets."

Adolescent↗
PubMed2000

Preschoolers' knowledge about strategies in coping with other's disgust evoked by immoral actions.

40 preschoolers in Exp. 1 and 22 in Exp. 2 (mean ages were both 5:11) were shown short stories presented as colored videotaped pictures with explanatory narrations. In each story a recipient felt disgusted by an agent's action. In Exp. 1 the agent's action was immoral. The participants were asked to tell how the agent would behave, supposing they were the agent themselves. About 80% of their answers were prosocial. In Exp. 2, two kinds of story were shown. In one, the agent hurt the recipient intentionally; in the other, by accident. Almost all answers in both kinds of story were prosocial. Furthermore, over a third of the participants told the reasons for their answers, considering the recipient's emotion, even when the agent's action was intentional and immoral. These findings show that the preschoolers had suitable knowledge about the agent's strategies in coping with the recipient's disgust.

Adaptation, Psychological↗
PubMed2000

[Clinical evaluation in oral lichen planus with chronic hepatitis C: the role of interferon treatment].

Hepatitis C virus (HCV) infection induces a variety of extrahepatic manifestations such as oral lichen planus (OLP). To clarify the role of HCV in the development of OLP, we investigated the occurrence of OLP in patients with chronic hepatitis C treated with interferon (IFN). Of 275 patients with chronic hepatitis C, 6 developed OLP during the IFN treatment. However, OLP developed in none of 230 patients with chronic hepatitis C who did not undergo the IFN therapy. The IFN treatment in chronic hepatitis C patients developed OLP significantly, as compared with the non-treated group (p < 0.05). 4 of 6 patients who developed OLP during the IFN treatment had a complete response with normalization of ALT levels and undetectable HCV RNA after the treatment. There were no significant correlations between the effect of the IFN treatment and outcome of OLP. Furthermore, 3 of the 6 patients developed OLP, when serum HCV RNA became negative. These results suggest that direct viral factors may not be important in the pathogenesis of OLP in patients with chronic hepatitis C. Immunological changes caused by IFN may play a role in the development of OLP associated with HCV infection.

Adolescent↗
PubMed2000

[Effects of the gene transfer into sperm mediated by liposomes on sperm motility and fertilization in vitro].

To clarify the problems of gene transfer in the fertility clinic, we investigated the safety and effectiveness of the gene transfer of mouse sperm using the lipofection method. We used the pCAGGS-lacZ plasmid connected with cytomegarovirus enhancer/chicken beta-actin promoter as an adventitious gene. After incubation of the DNA-liposome complex and mouse sperm of epididymis in the medium, we investigated the sperm motility after gene transfer, in vitro fertilization rate of the gene transferred sperm, and gene expression of the fertilized ovum and fetus. Sperm motility was lowered significantly with the increase in DNA density. The fertilization rate for in vitro fertilization was lowered significantly with the increase in DNA density. Gene expression was observed in some of the fertilized ova. In the fetus 12.5 days after embryo transfer, gene transfer was confirmed by the PCR method, but we could not find gene expression by X-gal staining. We proved that the sperm with a gene transferred by the lipofection method could fertilize the ovum and transfer adventitious gene to ova. We speculate that sperm motility and fertility rate were lowered because the introduction of DNA and the DNA-liposome complex destroyed parts of the cell. Development of a sperm fractionation method for DNA transfer and establishment of a method for effective and safe DNA transfer are awaited.

Animals↗
PubMed2000

[A case of 19th year pulmonary metastasis after radical mastectomy for breast cancer].

A 72-year-old woman was admitted to our hospital for further evaluation of a abnormal shadow in left middle lung field. The patient had undergone right mastectomy for infiltrating ductal carcinoma 19 years ago. She had no symptom, but had a time of mass X-ray screening this year. Chest CT finding showed a nodule 2 cm in diameter with slight irregular margin in S6 of left lung. We couldn't determine preoperatively that this tumor was a metastatic lesion or a primary lung cancer. And first, tumor was taken out for intraoperative frozen section diagnosis. Pathologist didn't diagnose whether this tumor was a metastatic or primary. So, we performed left lower lobectomy and mediastinal lymphadenectomy. On postoperative histopathologic finding lung cancer resembled well previous breast cancer. In immunohistochemical study cancer cells from lung and breast of the patient were respectively positive for anti Estrogen Receptor (ER) and anti Gross Cystic Disease Fluid Protein-15 (GCDFP-15). In conclusion lung cancer was diagnosed as a metastatic lesion from breast cancer 19 years ago. The patient has been well 2 years postoperatively without recurrence. In this case immunohistochemical examination was very useful for differentiation metastatic lesion and primary one.

Aged↗
PubMed2000

[Clinical data obtained through coagulation testing suggests that hypothermia exerts influence on a patient's blood coagulation reaction].

It often takes longer to achieve hemostasis when performing an operation on a patient in cerebral hypothermia therapy than in a normal patient, despite the lack of abnormal clinical blood coagulation findings, and this study was conducted to investigate the cause of delays in coagulation in patients with hypothermia. In this study, 93 samples of plasma were collected at our center from 10 patients(7 men and 3 women; mean age, 33.7) who were in cerebral hypothermia therapy with a urinary bladder temperature maintained at 32-34 degrees C. Each sample was divided into two, and PT(prothrombin time) and APTT(activated partial thromboplastin time) were measured at the normal analysis temperature of 37 degrees C in one sample, and at the hypothermia temperature of 32-34 degrees C in the other sample. The results showed that PT and APTT tended to shorter at 37 degrees C, than those measured at 32-34 degrees C. Thus, we suggest that it is necessary to regulate the temperature of patients with accidental hypothermia or in whom hypothermia therapy is performed.

Adult↗
PubMed1999

C-terminal residues 621-635 of protein S are essential for binding to factor Va.

Protein S is anticoagulant in the absence of activated protein C because of direct interactions with coagulation Factors Xa and Va. Synthetic peptides corresponding to amino acid sequences of protein S were tested for their ability to inhibit prothrombinase activity. The peptide containing the C-terminal sequence of protein S, residues 621-635 (PSP14), reversibly inhibited prothrombinase activity in the presence but not in the absence of Factor Va (K(i) approximately 2 microM). PSP14 inhibition of prothrombinase was independent of phospholipids but could be competitively overcome by increasing Factor Xa concentrations, suggesting that the C-terminal region of protein S may compete for a Factor Xa binding site on Factor Va. Studies using peptides with amino acid substitutions suggested that lysines 630, 631, and 633 were critical residues. PSP14 inhibited Factor Va activity in Factor Xa-one-stage clotting assays. PSP14 inhibited protein S binding to immobilized Factor Va. When preincubated with protein S, antibodies raised against PSP14 inhibited binding of protein S to Factor Va and blocked inhibition of prothrombinase activity by protein S. These results show that the C-terminal region of protein S containing residues 621-635 is essential for binding of protein S to Factor Va and that this interaction contributes to anticoagulant action.

Amino Acid Sequence↗
PubMed1999

Enhancement of cellulose production by expression of sucrose synthase in Acetobacter xylinum.

Higher plants efficiently conserve energy ATP in cellulose biosynthesis by expression of sucrose synthase, in which the high free energy between glucose and fructose in sucrose can be conserved and used for the synthesis of UDP-glucose. A mixture of sucrose synthase and bacterial cellulose synthase proceeded to form UDP-glucose from sucrose plus UDP and to synthesize 1,4-beta-glucan from the sugar nucleotide. The mutant sucrose synthase, which mimics phosphorylated sucrose synthase, enhanced the reaction efficiency (Vmax/Km) on 1,4-beta-glucan synthesis, in which the incorporation of glucose from sucrose was increased at low concentrations of UDP. Because UDP formed after glucosyl transfer can be directly recycled with sucrose synthase, UDP-glucose formed appears to show high turnover with cellulose synthase in the coupled reaction. The expression of sucrose synthase in Acetobacter xylinum not only changed sucrose metabolism but also enhanced cellulose production, in which UDP-glucose was efficiently formed from sucrose. Although the level of UDP-glucose in the transformant with mutant sucrose synthase cDNA was only 1.6-fold higher than that in plasmid-free cells, the level of UDP was markedly decreased in the transformant. The results show that sucrose synthase serves to channel carbon directly from sucrose to cellulose and recycles UDP, which prevents UDP build-up in cellulose biosynthesis.

Journal Article↗