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31.
Camhi SM Bray GA Bouchard C Greenway FL Johnson WD Newton RL Ravussin E Ryan DH Smith SR Katzmarzyk PT 《Obesity (Silver Spring, Md.)》2011,19(2):402-408
The purpose of this study was to examine sex and race differences in the relationship between anthropometric measurements and adiposity in white and African-American (AA) adults. Visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) areas were measured with computed tomography (CT). Fat mass (FM) was measured with dual-energy-X-ray absorptiometry (DXA). Correlation coefficients were used to assess the relationship of waist circumference (WC) and BMI to VAT, SAT, and FM within sex-by-race groups. General linear models were used to compare relationships between WC or BMI, and adiposity across sex and race, within age groups (18-39 and 40-64 years). The sample included 1,667 adults (men: 489 white; 120 AA; women: 666 white, 392 AA). WC and BMI correlations were highest for FM and SAT compared to VAT. Women had higher FM levels than men regardless of WC, but the sex difference in FM was attenuated in younger AA adults with a high BMI. For a given level of WC or BMI, women had higher levels of SAT than men; however, significant interactions indicated that the relationship was not consistent across all levels of BMI and WC. Sex and race differences in VAT varied significantly with WC and BMI. In general, white adults had higher levels of VAT than AA adults at higher levels of BMI and WC. Sex differences, and in some instances race differences, in the relationships between anthropometry and fat-specific depots demonstrate that these characteristics need to be considered when predicting adiposity from WC or BMI. 相似文献
32.
Hu M Lin X Du Q Miller EJ Wang P Simms HH 《American journal of physiology. Lung cellular and molecular physiology》2005,288(2):L266-L274
Delayed polymorphonuclear leukocyte (PMN) apoptosis exacerbates acute lung injury. To reach the alveolar spaces, PMNs must migrate across both pulmonary endothelial and epithelial cell layers. We hypothesized that transmigration across the endothelium-epithelium bilayer suppresses PMN apoptosis and sought to elucidate the underlying mechanisms. PMNs freshly isolated from normal volunteers were allowed to migrate across polycarbonate membranes alone or membranes coated with a bilayer of human lung endothelial and epithelial cells. After migration toward different chemoattractants (IL-8, formyl-Met-Leu-Phe, or leukotriene B(4)), PMN apoptosis and caspase activities were assessed by annexin V, histology, and enzymatic assays, respectively. Messenger RNA and specific protein expression in three receptor ligand-mediated, apoptosis-inducing pathways (Fas, TNF-alpha, and TNF-related apoptosis-inducing ligand) were further examined by gene array, RT-PCR, flow cytometry, and Western blot analyses. The data demonstrated that transbilayer migration suppressed PMN apoptosis, and this effect was not chemoattractant type specific. Kinetic analyses further showed that the delay of apoptosis was sustained to at least 18 h. Transbilayer migration caused significant decreases in caspase (-3, -8, and -9) activities. The changes in apoptosis-related gene expression support the survival role of transbilayer migration. Furthermore, the reduced apoptosis was correlated with downregulation of Fas ligand and TNF receptor 1 expression. Our data reveal that migration across a lung endothelium-epithelium bilayer suppresses PMN apoptosis. The decreased activity and/or expression of proapoptotic proteins may provide possible targets for the regulation of inappropriate delay in PMN apoptosis during lung inflammation and injury. 相似文献
33.
Lomas-Neira J Chung CS Grutkoski PS Dunican A Simms HH Cioffi WG Ayala A 《Cytokine》2005,31(3):169-179
Neutrophil associated lung injury is identified with a variety of local and systemic priming insults. In vitro studies have shown that TNF-alpha mediated suppression of neutrophil apoptosis is due to the secretion of interleukin-8 (IL-8), a human chemokine shown to alter neutrophil chemotaxis. Our initial in vitro antibody neutralization studies with neutrophil chemotactic proteins, keratinocyte-derived chemokine (KC) and macrophage inflammatory protein-2alpha (MIP-2alpha), mouse IL-8 homologues, indicate that MIP-2alpha but not KC appears to mediate TNF-alpha suppression of mouse neutrophil apoptosis. Therefore, we hypothesized that in vivo neutralization of KC or MIP-2alpha during an initial priming insult would produce differential effects on the extent of lung injury by restoring normal neutrophil apoptotic function. To assess this, mice were hemorrhaged followed with septic challenge at 24 h. Antibody against KC or MIP-2alpha or a nonspecific IgG was given during resuscitation immediately following hemorrhage. Anti-MIP-2alpha treatment resulted in a significant reduction in lung tissue IL-6 and myeloperoxidase levels. Percentage of neutrophil apoptosis increased significantly in the anti-KC group. Tissue and plasma KC and MIP-2alpha were reduced in their respective treatment groups. These data suggest that KC and MIP-2alpha differ in their mediation of neutrophil function (apoptosis and chemotaxis) and contribution to the pathogenesis of lung injury following hemorrhage subsequent to sepsis. 相似文献
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While screening for plant homologs of telomeric-complex proteins, we isolated a cDNA for the Terminal acidic SANT 1 (Tacs1) gene of maize, encoding a 45-kDa protein with a C-terminal Myb/SANT-like domain. Gene expression and protein modeling data indicate that the TACS1 protein may function in chromatin remodeling within shoot primordia or other meristem-containing tissues. 相似文献
36.
37.
Roots of intact wheat plants were grown for 7-12 d in stagnant nutrient solution, containing 0.1% agar, to mimic the lack of convection in waterlogged soil. Net K+ and P uptakes by seminal and nodal roots were measured separately using a split root system. For seminal roots in stagnant solution, net uptakes as a percentage of aerated roots were between 0% and 16% for P, while K+ ranged between 15% uptake and 54% loss. For the more waterlogging-tolerant nodal roots, net uptakes in stagnant nutrient solution, as a percentage of aerated roots, were 31-73% for P and 69-115% for K+. Elongation rates of nodal roots in stagnant nutrient were about 35-43% of those for roots in aerated solution. This partial inhibition occurred in these nodal roots despite their 15% porosity (v/v). Elevation of O2 partial pressures around the shoots to 40 kPa and then to 80 kPa substantially accelerated nodal root elongation in stagnant solution, demonstrating that most of the inhibition seen with ambient O2 around the shoots was associated with a restricted O2 supply to these nodal roots. Thus, in wheat nodal roots, with a partial pressure of 20 kPa O2 around the shoots, O2 diffusion from the shoots did not completely relieve the restrictions on elongation resulting from stagnancy in the nutrient solution. These results contrast with those in the literature for rice, in which roots function efficiently in stagnant solutions (0.1% agar). So, when wheat roots are aerenchymatous there are still restrictions to O2 diffusion in the gas space continuum between the atmosphere and the functional tissues of the roots. This poor acclimation must have been due to inefficiency of the aerenchymatous axes, which may include persistence of anoxic steles, and/or restricted O2 diffusion in other parts of the gas space continuum, in either the shoots and shoot-root junction or in the root tip. 相似文献
38.
Asian elephants (Elephas maximus) in western zoos are likely to become extinct unless elephants are regrouped into breeding units or additional elephants are imported from range States. There have been proposals for the export of elephants from elephant camps in Sumatra, Indonesia. In exchange, zoos would be expected to provide funds or support ‘in kind’ for the camps or for the conservation of wild elephants. Most of the elephants in the Sumatran camps were captured because of crop‐raiding problems around protected areas or because elephant habitat has been and continues to be lost to development schemes and illegal conversion of protected areas to agriculture. Capture‐related mortality rates are high and conditions in the camps are poor, with low standards of veterinary care and husbandry. This is partly due to over‐crowding and inadequate budgets. It might seem, therefore, that the loan of elephants to western zoos would improve the lot of these elephants and reduce the pressures on the camps. However, we show that both total and annual demand for Asian elephants, and particularly Sumatran elephants (E. m. sumatranus), by western zoos are low, and consequently the resources generated by any loan scheme would be limited. Elephant loan schemes are unlikely to have significant beneficial impact on either the conservation or welfare of elephants in Sumatra. More importantly, a credible loan scheme would require a permanent moratorium on the capture of wild elephants in Sumatra. Such a moratorium is needed to prevent illicit captures for sale or loan. At present, wild elephants are caught to replace those that die at the camps or are moved to other facilities. Without a moratorium, the loan of elephants to overseas zoos would contribute directly to reductions in wild elephant populations in Sumatra. However, a moratorium is likely to prove impossible to enforce, and this alone should call into question the desirability of any loan scheme. Zoo Biol 25:235–246, 2006. © 2006 Wiley‐Liss, Inc. 相似文献
39.
Choi BS Sondel PM Hank JA Schalch H Gan J King DM Kendra K Mahvi D Lee LY Kim K Albertini MR 《Cancer immunology, immunotherapy : CII》2006,55(7):761-774
Purpose: We conducted a phase I trial of interleukin 2 (IL-2) in combination with chimeric 14.18 (ch14.18) and murine R24 antibodies
to determine the maximal tolerated dose (MTD), immunological effects, and toxicity of this treatment combination. Experimental Design: Twenty-seven patients with either melanoma (23 patients) or sarcoma (4 patients) were enrolled to receive a combination
therapy with ch14.18 and R24 antibodies together with continuous infusion of Roche IL-2 (1.5×106 U/m2/day, 26 patients) or Chiron IL-2 (4.5×106 U/m2/day, 1 patient) given 4 days/week for 3 weeks. The antibodies ch14.18 (2–7.5 mg/m2/day) and R24 (1–10 mg/m2/day) were scheduled to be administered for 5 days during the second week of IL-2 therapy. Results: When given in combination in this study, the MTD for ch14.18 was 5 mg/m2/day and the MTD for R24 was 5 mg/m2/day. Dose-limiting toxicities were severe allergic reactions to both ch14.18 and R24 as well as pain related to ch14.18.
This ch14.18 MTD was lower than the 7.5 mg/m2/day MTD previously determined for ch14.18 given alone with the same dose and schedule of IL-2. Immunological effects included
the induction of lymphokine-activated killer (LAK) activity and antibody-dependent cell-mediated cytoxicity (ADCC). Anti-idiotype
response to ch14.18 was seen in six patients, including two melanoma patients who had a partial response to treatment. In
addition to two partial responses, four patients had a stable disease and one patient remained without any evidence of disease.
Conclusions: Immunotherapy with IL-2 in combination with ch14.18 and R24 antibodies augments LAK function and ADCC measured in vitro
in all patients. While there exist theoretical advantages of combining these two antibodies, the MTD of ch14.18 and of R24
were lower than the MTD of each antibody in prior studies evaluating single antibody therapy with IL-2. As such, the combination
of these two antibodies together with IL-2 therapy appeared to influence the MTD and toxicity of each of the administered
antibodies.
This work is supported by NIH grants M01-RR03186, R01-CA32685, and P30-CA14520 相似文献
40.
Mark R. Albertini Jacquelyn A. Hank Brian Gadbaw Jordan Kostlevy Jennifer Haldeman Heidi Schalch Jacek Gan KyungMann Kim Jens Eickhoff Stephen D. Gillies Paul M. Sondel 《Cancer immunology, immunotherapy : CII》2012,61(12):2261-2271
Phase I testing of the hu14.18-IL2 immunocytokine in melanoma patients showed immune activation, reversible toxicities, and a maximal tolerated dose of 7.5?mg/m2/day. In this phase II study, 14 patients with measurable metastatic melanoma were scheduled to receive hu14.18-IL2 at 6?mg/m2/day as 4-h intravenous infusions on Days 1, 2, and 3 of each 28?day cycle. Patients with stable disease (SD) or regression following cycle 2 could receive two additional treatment cycles. The primary objective was to evaluate antitumor activity and response duration. Secondary objectives evaluated adverse events and immunologic activation. All patients received two cycles of treatment. One patient had a partial response (PR) [1 PR of 14 patients?=?response rate of 7.1?%; confidence interval, 0.2?C33.9?%], and 4 patients had SD and received cycles 3 and 4. The PR and SD responses lasted 3?C4?months. All toxicities were reversible and those resulting in dose reduction included grade 3 hypotension (2 patients) and grade 2 renal insufficiency with oliguria (1 patient). Patients had a peripheral blood lymphocytosis on Day 8 and increased C-reactive protein. While one PR in 14 patients met protocol criteria to proceed to stage 2 and enter 16 additional patients, we suspended stage 2 due to limited availability of hu14.18-IL2 at that time and the brief duration of PR and SD. We conclude that subsequent testing of hu14.18-IL2 should involve melanoma patients with minimal residual disease based on compelling preclinical data and the confirmed immune activation with some antitumor activity in this study. 相似文献