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排序方式: 共有509条查询结果,搜索用时 15 毫秒
61.
Eagar TN Turley DM Padilla J Karandikar NJ Tan L Bluestone JA Miller SD 《Journal of immunology (Baltimore, Md. : 1950)》2004,172(12):7442-7450
Intravenous treatment with Ag (peptide)-coupled, ethylene carbodiimide-fixed syngeneic splenocytes (Ag-SP) is a powerful method to induce anergy in vitro and peripheral T cell tolerance in vivo. In this study, we examined the effects of Ag-SP administration on T cell activity ex vivo and in vivo using OVA-specific DO11.10 TCR transgenic T cells. Although treatment with OVA323-339-SP resulted in a strong inhibition of peptide-specific T cell recall responses in vitro, examination of the immediate effects of Ag-SP treatment on T cells in vivo demonstrated that tolerogen injection resulted in rapid T cell activation and proliferation. Although there was an increase in the number of OVA-specific DO11.10 T cells detected in the lymphoid organs, these previously tolerized T cells were strongly inhibited in mounting proliferative or inflammatory responses upon rechallenge in vivo with peptide in CFA. This unresponsiveness was reversible by treatment with anti-CTLA-4 mAb. These results are consistent with the hypothesis that Ag-SP injection induces a state of T cell anergy that is maintained by CTLA-4 engagement. 相似文献
62.
Domínguez MG Vásquez AI Troyo R Ortiz-Aranda M Padilla JR Hernández-Zaragoza G Rivas F Rivera H 《Genetic counseling (Geneva, Switzerland)》2006,17(4):413-419
We characterized two Y-ring microchromosomes (MC) found in an azoospermic patient with Turner stigmata (case A) and a male infant with hypospadias (case B). The karyotypes, as assessed by banding, FISH, and STRs/STSs analyses, were 46,X,r(Y).ish r(Y)(p11.3q11.222)(SRY+,DYZ3+) and 46,X,+r(Y)/45,X.ish r(Y)(p 11.2q11.2)(Xp/Yp-,SRY+,DYZ3+) respectively. In both cases, we evaluated the association of each MC with the centromere of the nearest and second nearest chromosomes in G-banded metaphases by means of measuring the intervening distance according to two criteria: < or =1 time or < or =3 times the size of the MC in each metaphase. The case A's MC was associated 84 times in 98 cells according to the latter or less strict criterion and two times in 98 cells according to the strict criterion; the corresponding values for case B were 84 and two in 95 cells respectively. The centromeric association appears to be related to centromeric attraction mediated by heterochromatin or centromere-specific proteins, the replication time, and the Rabl orientation. 相似文献
63.
Puvabanditsin S Garrow E Umaru S Padilla J Chowdawarapu S Biswas A 《Genetic counseling (Geneva, Switzerland)》2006,17(2):167-171
Otocephaly is a rare lethal malformation of the first and second branchial arches. We report two infants with otocephaly and failed resuscitation. Both infants had pulmonary malformations: pulmonary hypoplasia and two-lobed right lung. We report these rare associations with a brief review of the literature. 相似文献
64.
Eltit JM Feng W Lopez JR Padilla IT Pessah IN Molinski TF Fruen BR Allen PD Perez CF 《The Journal of biological chemistry》2010,285(49):38453-38462
Previously, we have shown that lack of expression of triadins in skeletal muscle cells results in significant increase of myoplasmic resting free Ca(2+) ([Ca(2+)](rest)), suggesting a role for triadins in modulating global intracellular Ca(2+) homeostasis. To understand this mechanism, we study here how triadin alters [Ca(2+)](rest), Ca(2+) release, and Ca(2+) entry pathways using a combination of Ca(2+) microelectrodes, channels reconstituted in bilayer lipid membranes (BLM), Ca(2+), and Mn(2+) imaging analyses of myotubes and RyR1 channels obtained from triadin-null mice. Unlike WT cells, triadin-null myotubes had chronically elevated [Ca(2+)](rest) that was sensitive to inhibition with ryanodine, suggesting that triadin-null cells have increased basal RyR1 activity. Consistently, BLM studies indicate that, unlike WT-RyR1, triadin-null channels more frequently display atypical gating behavior with multiple and stable subconductance states. Accordingly, pulldown analysis and fluorescent FKBP12 binding studies in triadin-null muscles revealed a significant impairment of the FKBP12/RyR1 interaction. Mn(2+) quench rates under resting conditions indicate that triadin-null cells also have higher Ca(2+) entry rates and lower sarcoplasmic reticulum Ca(2+) load than WT cells. Overexpression of FKBP12.6 reverted the null phenotype, reducing resting Ca(2+) entry, recovering sarcoplasmic reticulum Ca(2+) content levels, and restoring near normal [Ca(2+)](rest). Exogenous FKBP12.6 also reduced the RyR1 channel P(o) but did not rescue subconductance behavior. In contrast, FKBP12 neither reduced P(o) nor recovered multiple subconductance gating. These data suggest that elevated [Ca(2+)](rest) in triadin-null myotubes is primarily driven by dysregulated RyR1 channel activity that results in part from impaired FKBP12/RyR1 functional interactions and a secondary increased Ca(2+) entry at rest. 相似文献
65.
Padilla DJ McDonough P Behnke BJ Kano Y Hageman KS Musch TI Poole DC 《American journal of physiology. Heart and circulatory physiology》2006,291(5):H2439-H2444
Microcirculatory red blood cell (RBC) hemodynamics are impaired within skeletal muscle of Type I diabetic rats (Kindig CA, Sexton WL, Fedde MR, and Poole DC. Respir Physiol 111: 163-175, 1998). Whether muscle microcirculatory dysfunction occurs in Type II diabetes, the more prevalent form of the disease, is unknown. We hypothesized that Type II diabetes would reduce the proportion of capillaries supporting continuous RBC flow and RBC hemodynamics within the spinotrapezius muscle of the Goto-Kakizaki Type II diabetic rat (GK). With the use of intravital microscopy, muscle capillary diameter (d(c)), capillary lineal density, capillary tube hematocrit (Hct(cap)), RBC flux (F(RBC)), and velocity (V(RBC)) were measured in healthy male Wistar (control: n = 5, blood glucose, 105 +/- 5 mg/dl) and male GK (n = 7, blood glucose, 263 +/- 34 mg/dl) rats under resting conditions. Mean arterial pressure did not differ between groups (P > 0.05). Sarcomere length was set to a physiological length ( approximately 2.7 mum) to ensure that muscle stretching did not alter capillary hemodynamics; d(c) was not different between control and GK rats (P > 0.05), but the percentage of RBC-perfused capillaries (control: 93 +/- 3; GK: 66 +/- 5 %), Hct(cap), V(RBC), F(RBC), and O(2) delivery per unit of muscle were all decreased in GK rats (P < 0.05). This study indicates that Type II diabetes reduces both convective O(2) delivery and diffusive O(2) transport properties within muscle microcirculation. If these microcirculatory deficits are present during exercise, it may provide a basis for the reduced O(2) exchange characteristic of Type II diabetic patients. 相似文献
66.
Changes in the distribution and abundance of Dreissena polymorpha within lakes through time 总被引:1,自引:0,他引:1
Dreissena polymorpha population densities and biomass were followed in three Belarusian lakes with different trophic status over a 12-year period
subsequent to initial colonization. In all three lakes zebra mussel population densities did not change once they reached
a maximum. Application of the Ramcharan et al. [1992. Canadian Journal of Fisheries and Aquatic Sciences 49: 2611–2620] model
for predicting population dynamics of zebra mussels was accurate for two of the three lakes studied. Population density appears
to depend on the time since initial colonization, relative abundance of substrate available for colonization, lake morphometry
and trophic type. Zebra mussel distribution within lakes was highly patchy, but the degree of dispersion decreased over time
after initial colonization, which may be a result of saturation of suitable substrates by zebra mussels as populations increase
and reach carrying capacity. In lakes where submerged macrophytes are the dominant substrate for zebra mussel attachment,
populations may be less stable than in lakes with a variety of substrates, which will have a more balanced age distribution,
and be less impacted by year to year variation in recruitment. Dreissena polymorpha usually reach maximum population density 7–12 years after initial introduction. However, the timing of initial introduction
is often very difficult to determine. Both European and North American data suggest that zebra mussels reach maximum density
in about 2–3 years after populations are large enough to be detected. 相似文献
67.
Cossío-Bayúgar R Miranda-Miranda E Narváez Padilla V Olvera-Valencia F Reynaud E 《Journal of insect physiology》2012,58(5):628-633
The cattle tick Rhipicephalus microplus, is one of the most damaging livestock ectoparasites. Tropical tick infestation limits the introduction of high-yield bovine varieties because they do not have immunity to the diseases transmitted by these ectoparasites. This tick is usually controlled with chemical acaricides but their indiscriminate use has created resistant populations. The discovery of new molecules that can be used for tick control is urgent. Based on the knowledge that octopamine, a biogenic amine analog to epinephrine, is central to the regulation of oviposition in several studied arthropods and that an imbalance in octopamine release causes sterility in a Drosophila model. Tyramine, octopamine and epinastine and 83 adrenergic compounds classified by their effect in the vertebrate systems were screened for their ability to block oviposition in Rhipicephalus microplus. Of these molecules, we found that 10 alpha-agonists, 3 alpha-antagonists, 5 beta-adrenergic agonists, 7 beta-antagonists and Norepinephrine were able to inhibit oviposition in this tick at pharmacological concentrations. Surprisingly, tyramine appears to be more potent than octopamine. The probable physiological causes of this inhibition are discussed. Our results suggest that although there are alpha adrenergic-like receptors in the tick, they do not behave in a manner completely analogous to their vertebrate counterparts. 相似文献
68.
Castellanos María Eugenia Bardají Azucena Menegon Michela Mayor Alfredo Desai Meghna Severini Carlo Menéndez Clara Padilla Norma 《Malaria journal》2012,11(1):1-5
Background
To document the status of imported malaria infections and estimate the costs of treating of patients hospitalized with the diagnosis of imported malaria in the Slovak Republic during 2003 to 2008.Case study
Calculating and comparing the direct and indirect costs of treatment of patients diagnosed with imported malaria (ICD-10: B50 - B54) who used and not used chemoprophylaxis. The target sample included 19 patients diagnosed with imported malaria from 2003 to 2008, with 11 whose treatment did not include chemoprophylaxis and eight whose treatment did.Results
The mean direct cost of malaria treatment for patients without chemoprophylaxis was 1,776.0 EUR, and the mean indirect cost 524.2 EUR. In patients with chemoprophylaxis the mean direct cost was 405.6 EUR, and the mean indirect cost 257.4 EUR.Conclusions
The analysis confirmed statistically-significant differences between the direct and indirect costs of treatment with and without chemoprophylaxis for patients with imported malaria. 相似文献69.
70.
Rodolfo Valdés Andrés Tamayo Marcos González Sigifredo Padilla Déborah Geada William Ferro Lorely Milá Leonardo Gómez Rosario Alemán Alberto Leyva Cristina García Otto Mendoza Tatiana Alvarez Lamay Dorta Yanet Villega Dobián Cecilia Hasel Aragón Tatiana González Maylín La O Jorge López 《Biotechnology and Bioprocess Engineering》2012,17(1):145-159
Monoclonal antibody (mAb) production methods (ascites, in vitro technologies, transgenic animals, and dicot or monocot transgenic plants; moss, algae) have been improved since they were first developed in 1975. In this study, we illustrate a summary of a study case in which mice, a hollow fiber system, and tobacco transgenic plants were assessed for the production of mAb for vaccine manufacturing and vaccine production. 相似文献