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31.
Toshihiro Sera Hideki Fujioka Hideo Yokota Akitake Makinouchi Ryutaro Himeno Robert C Schroter Kazuo Tanishita 《Journal of applied physiology》2004,96(5):1665-1673
Airway compliance is a key factor in understanding lung mechanics and is used as a clinical diagnostic index. Understanding such mechanics in small airways physiologically and clinically is critical. We have determined the "morphometric change" and "localized compliance" of small airways under "near"-physiological conditions; namely, the airways were embedded in parenchyma without dehydration and fixation. Previously, we developed a two-step method to visualize small airways in detail by staining the lung tissue with a radiopaque solution and then visualizing the tissue with a cone-beam microfocal X-ray computed tomography system (Sera et al. J Biomech 36: 1587-1594, 2003). In this study, we used this technique to analyze changes in diameter and length of the same small airways ( approximately 150 microm ID) and then evaluated the localized compliance as a function of airway generation (Z). For smaller (<300-microm-diameter) airways, diameter was 36% larger at end-tidal inspiration and 89% larger at total lung capacity; length was 18% larger at end-tidal inspiration and 43% larger at total lung capacity than at functional residual capacity. Diameter, especially at smaller airways, did not behave linearly with V(1/3) (where V is volume). With increasing lung pressure, diameter changed dramatically at a particular pressure and length changed approximately linearly during inflation and deflation. Percentage of airway volume for smaller airways did not behave linearly with that of lung volume. Smaller airways were generally more compliant than larger airways with increasing Z and exhibited hysteresis in their diameter behavior. Airways at higher Z deformed at a lower pressure than those at lower Z. These results indicated that smaller airways did not behave homogeneously. 相似文献
32.
Yoshida H Katayose Y Unno M Suzuki M Kodama H Takemura S Asano R Hayashi H Yamamoto K Matsuno S Kudo T 《Cancer immunology, immunotherapy : CII》2003,52(2):97-106
4-1BB ligand (4-1BBL), a member of the tumor necrosis factor (TNF) superfamily, interacts with 4-1BB (CDw137) expressed on activated T cells and delivers a costimulatory signal for T cell activation and growth. Various studies have demonstrated a role for murine 4-1BB in immune function, but relatively few investigations of human 4-1BB have been conducted. Here we report on the construction of a recombinant E1/E3-deleted adenovirus encoding human 4-1BBL (Ad4-1BBL) and its stimulation of antitumor immunity. Ad4-1BBL was able to efficiently infect several human adenocarcinoma cell lines and induce 4-1BBL expression on the cell surface within 24 h, this enhancing the antitumor activity not only of lymphokine-activated killer cells with a T cell phenotype (T-LAK) but also naive peripheral blood mononuclear cells (PBMC). This antitumor activity with T-LAK cells was further enhanced by addition of bispecific antibody (BsAb; anti-MUC1xanti-CD3). Cocultivation of Ad4-1BBL-infected tumor cells with either T-LAK cells or PBMC resulted in significant elevation of interferon-gamma (IFN-gamma), interleukin-2 (IL-2), and granulocyte-macrophage colony-stimulating factor (GM-CSF) production. Furthermore, remarkable tumor growth inhibition was observed in cholangiocarcinoma-grafted severe combined immunodeficient (SCID) mice to which Ad4-1BBL and T-LAK cells were administered when tumor size exceeded 5 mm in diameter. These results provide strong evidence in support of the efficacy of adenovirally delivered 4-1BBL for genetic immunotherapy of cancer. 相似文献
33.
34.
Effects of polygyny and consanguinity on high fertility in the rural Arab population in South Jordan
Based on the authors' interview survey for 608 randomly selected women of the rural Arab population in the South Ghor district of Jordan, this paper examined the effects of polygyny and consanguinity on high fertility, which was recognized as natural fertility. The prevalence of polygynous and consanguineous marriages was 28.0% and 58.1%, respectively, largely reflecting the population's traditional marriage customs. The findings highlighted a significantly higher total marital fertility rate (TMFR) in the monogamous wives (10.5) than in the senior polygynous (8.1) and junior polygynous wives (8.6); the TMFR did not significantly differ among the wives of non-consanguineous, first-cousin and second-cousin marriages. The formation of polygynous marriage was decided by the husband, mostly as a result of his senior wife's infecundity or sub-fecundity, and the age of the husband at marriage to his junior polygynous wife was high in many cases, leading to a decline in this wife's fecundity. 相似文献
35.
Murayama N Matsunaga A Tangbanluekal L Tantawiwat S Ohtsuka R 《Journal of biosocial science》2003,35(2):243-261
The use of contraceptives has become prevalent among females in Thailand in the past 20 years, and oral contraceptive use has been suggested to trigger changes in fat intake, energy expenditure, fat metabolism and blood pressure. Based on field investigations of 391 married women aged 20 years or over in Yasothon Province, North-east Thailand, this study aims to elucidate the effects of oral contraceptive use on body mass index (BMI: kg/m2) and blood pressure, taking into account reproductive histories and socioeconomic conditions. The proportion of obese (BMI > or = 25) subjects was high in the age groups 30-39, 40-49 and 50-59, accounting for, respectively, 39.4%, 51.1% and 48.5% of these populations. The proportion of women with hypertension (90/140 mmHg) was 23.7%, 18.5% and 26.2% in the 40-49, 50-59 and 60-69 age groups. Current contraceptive practices in the studied population included sterilization by operation, oral contraception and injection. These methods accounted for 43.0%, 12.8% and 8.2% of the population, respectively. Sociodemographic factors such as reproductive history, years of education and household income were not significantly related to BMI or to blood pressure (ANOVA with age adjustment). In contrast, oral contraceptive users had significantly higher BMIs and diastolic blood pressures (p<0.01, ANOVA with age adjustment). Multiple regression analysis also revealed that oral contraceptive use was a weak but significant contributing factor to both high BMI and blood pressure when sociodemographic factors were taken into account and controlled for statistically. It can thus be concluded that the use of contraceptive pills, which contain oestrogen and progestin and are provided free of charge to Thai women, tend to increase BMI and to elevate blood pressure. 相似文献
36.
WuQiang F Yanase T Wei L Oba K Nomura M Okabe T Goto K Nawata H 《Biochemical and biophysical research communications》2003,311(4):987-994
Ad4BP/SF-1 plays key roles at all levels of the hypothalamic-pituitary-steroidogenic organ axis and its functional disruption causes endocrine disorders of these organs. However, only three human subjects with Ad4BP/SF-1 mutations have been reported to date, suggesting limited clinical significance as a cause of inborn adrenal or sexual abnormalities. We report the first functional characterization of a new variation found in the hinge region of human Ad4BP/SF-1, G146A. Resulting from a single nucleotide shift (GGG-->GCG), G146A bears slightly diminished transactivation activity evidenced by both adrenal specific cyp11A promoter and ovary specific cyp19 promoter II. The variation does not affect protein expression or stability, exhibiting no dominant negative effect. G146A has a normal interaction pattern with standard co-regulators and subnuclear distribution pattern, and can be considered as a nonsynonymous single nucleotide polymorphism, since it occurs in normals and patients with adrenal diseases. In normal Japanese the allele C frequency is 8%, while in a preliminary population of patients with adrenal diseases it is elevated to 30%; suggesting the G146A variation might be of clinical importance. 相似文献
37.
Moreira R Pinho JR Fares J Oba IT Cardoso MR Saraceni CP Granato C 《Canadian journal of microbiology》2003,49(8):503-507
The aims of this study were to (i) evaluate the prevalence and the incidence of hepatitis C virus (HCV) infection in hemodialysis patients in two different centers in S?o Paulo (Brazil), (ii) determine the time required to detect HCV infection among these patients by serology or PCR, (iii) establish the importance of alanine aminotransferase determination as a marker of HCV infection, and (iv) identify the HCV genotypes in this population. Serum samples were collected monthly for 1 year from 281 patients admitted to hospital for hemodialysis. Out of 281 patients, 41 patients (14.6%) were HCV positive; six patients seroconverted during this study (incidence = 3.1/1000 person-month). In 1.8% (5/281) of cases, RNA was detected before the appearance of antibodies (up to 5 months), and in 1.1% (3/281) of cases, RNA was the unique marker of HCV infection. The genotypes found were 1a, 1b, 3a, and 4a. The presence of genotype 4a is noteworthy, since it is a rare genotype in Brazil. These data pointed out the high prevalence and incidence of HCV infection at hemodialysis centers in Brazil and showed that routine PCR is fundamental for improving the detection of HCV carriers among patients undergoing hemodialysis. 相似文献
38.
Firefly luciferase can catalyze the formation of fatty acyl-CoA via fatty acyl-adenylate from fatty acid in the presence of ATP, Mg2+ and coenzyme A (CoA). A long chain fatty acyl-CoA (C16–C20), produced by luciferase from a North American firefly (Photinus pyralis) and a Japanese firefly (Luciola cruciata), was isolated and identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis. Of a number of substrates tested, linolenic acid (C18:3) and arachidonic acid (C20:4) appear to be suitable for acyl-CoA synthesis. This evidence suggests that firefly luciferase within peroxisomes of the cells in the photogenic organ may be a bifunctional enzyme, catalyzing not only the bioluminescence reaction but also the fatty acyl-CoA synthetic reaction. 相似文献
39.
Fujimori A Hashimoto H Araki R Saito T Sato S Kasama Y Tsutsumi Y Mori M Fukumura R Ohhata T Tatsumi K Abe M 《Radiation research》2002,157(3):298-305
The catalytic subunit of DNA-dependent protein kinase plays critical roles in nonhomologous end joining in repair of DNA double-strand breaks and V(D)J recombination. In addition to the SCID phenotype, it has been suggested that the molecule contributes to the polymorphic variations in radiosensitivity and susceptibility to cancer in mouse strains. Here we show the nucleotide sequence of approximately 193-kbp and 84-kbp genomic regions encoding the entire Prkdc gene (also known as DNA-PKcs) in the mouse and chicken, respectively. A large retroposon was found in intron 51 in the mouse but not in the human or chicken. Comparative analyses of the genome strongly suggested that the region contains only two genes for Prkdc and Mcm4; however, several conserved sequences and cis elements were also predicted. 相似文献
40.
Nathanael R. Hauck Hisayo Yamane Ryutaro Tao Amy F. Iezzoni 《Sexual plant reproduction》2002,15(1):39-46
. Gametophytic self-incompatibility (GSI) typically "breaks down" due to polyploidy in many Solanaceous species, resulting in self-compatible (SC) tetraploid individuals. However, sour cherry (Prunus cerasus L.), a tetraploid species resulting from hybridization of the diploid sweet cherry (P. avium L.) and the tetraploid ground cherry (P. fruticosa Pall.), is an exception, consisting of both self-incompatible (SI) and SC individuals. Since sweet cherry exhibits GSI with 13 S-ribonucleases (S-RNases) identified as the stylar S-locus product, the objectives were to compare sweet and sour cherry S-allele function, S-RNase sequences and linkage map location as initial steps towards understanding the genetic basis of SI and SC in sour cherry. S-RNases from two sour cherry cultivars that were the parents of a linkage mapping population were cloned and sequenced. The sequences of two S-RNases were identical to those of sweet cherry S-RNases, whereas three other S-RNases had unique sequences. One of the S-RNases mapped to the Prunus linkage group 6, similar to its location in sweet cherry and almond, whereas two other S-RNases were linked to each other but were unlinked to any other markers. Interspecific crosses between sweet and sour cherry demonstrated that GSI exists in sour cherry and that the recognition of common S-alleles has been maintained in spite of polyploidization. It is hypothesized that self-compatibility in sour cherry is caused by the existence of non-functional S-RNases and pollen S-genes that may have arisen from natural mutations. 相似文献