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11.
Limited data exist about patient preferences and self‐efficacy for different diets. We explored the preferences and self‐efficacy of primary care patients for reducing fat, reducing carbohydrates, or reducing calories. We conducted a self‐administered survey study of 71 primary care patients (response rate of 52%). Of patients, 59%, 53%, and 60% had high self‐efficacy for reducing fat, reducing carbohydrates, and reducing calories from their diet, respectively. Preferences were comparable, with 76% highly willing to reduce fat, 76% highly willing to reduce carbohydrates, and 72% of patients highly willing to reduce calories/portions. Female sex and higher BMI were associated with high self‐efficacy for all three dietary changes. A significantly higher proportion of nonwhites than whites had high self‐efficacy for reducing fat and reducing carbohydrates (P < 0.05). Obese patients in our study have similarly high willingness and self‐efficacy and comparable preferences for adopting changes consistent with three popular diets.  相似文献   
12.
Lactic acid is an environmentally benign organic acid that could be used as a raw material for biodegradable plastics if it can be inexpensively produced by fermentation. Two genes (IdhL andIdhD) encoding the L-(+) and D-(−) lactate dehydrogenases (L-LDH and D-LDH) were cloned fromLactobacillus sp., RKY2, which is a lactic acid hyper-producing bacterium isolated from Kimchi. Open reading frames ofIdhL for andIdhD for the L and D-LDH genes were 962 and 998 bp, respectively. Both the L(+)- and D(−)-LDH proteins showed the highest degree of homology with the L- and D-lactate dehydrogenase genes ofLactobacillus plantarum. The conserved residues in the catalytic activity and substrate binding of both LDHs were identified in both enzymes.  相似文献   
13.
The human indoleamine 2,3-dioxygenase (HuIDO) baculoviral construct, for expression of HuIDO protein with a hexa-histidine and FLAG (DYKDDDDK) tag, was produced using the BacPAK Baculovirus Expression System. HuIDO baculovirus was used to infect Sf21 insect cells to produce functionally active protein in large amounts. Conditions for protein purification by metal affinity chromatography were determined and optimized. Addition of haemin ensured optimal activity of the purified heme-containing oxygenase. The soluble purified protein was used to immunize a chicken to produce large quantities of polyclonal IgY against HuIDO. The anti-HuIDO IgY antibody specifically detected HuIDO produced by a range of cell types including transfectants and native HuIDO expression induced in IFN-gamma-stimulated cells. The antibody detected HuIDO in cell lysates by western blotting and in the cytoplasm of cells by microscopy. The antibody was unable to block the function of the enzyme, indicating that this antibody binds outside the active site of HuIDO.  相似文献   
14.
Arrest defective 1 (ARD1) is an acetyltransferase that is highly conserved across organisms, from yeasts to humans. The high homology and widespread expression of ARD1 across multiple species and tissues signify that it serves a fundamental role in cells. Human ARD1 (hARD1) has been suggested to be involved in diverse biological processes, and its role in cell proliferation and cancer development has been recently drawing attention. However, the subcellular localization of ARD1 and its relevance to cellular function remain largely unknown. Here, we have demonstrated that hARD1 is imported to the nuclei of proliferating cells, especially during S phase. Nuclear localization signal (NLS)-deleted hARD1 (hARD1ΔN), which can no longer access the nucleus, resulted in cell morphology changes and cellular growth impairment. Notably, hARD1ΔN-expressing cells showed alterations in the cell cycle and the expression levels of cell cycle regulators compared to hARD1 wild-type cells. Furthermore, these effects were rescued when the nuclear import of hARD1 was restored by exogenous NLS. Our results show that hARD1 nuclear translocation mediated by NLS is required for cell cycle progression, thereby contributing to proper cell proliferation.  相似文献   
15.
Gram-positive, aerobic, non-motile, pale-yellow, and rodshaped bacterium, designated as Gsoil 188T, was isolated from the soil of a ginseng field in Pocheon, South Korea. A phylogenetic analysis based on 16S rRNA gene sequence comparison revealed that the strain formed a distinct lineage within the genus Brevibacterium and was most closely related to B. epidermidis NBRC 14811T (98.4%), B. sediminis FXJ8.269T (98.2%), B. avium NCFB 3055T (98.1%), and B. oceani BBH7T (98.1%), while it shared less than 98.1% identity with the other species of this genus. The DNA G + C content was 68.1 mol%. The predominant quinone was MK-8(H2). The major fatty acids were anteiso-C15:0 and anteiso-C17:0. The cell wall peptidoglycan of strain Gsoil 188T contained meso-diaminopimelic acid. The major polar lipids were phosphatidylglycerol, diphosphatidylglycerol, and an unidentified aminolipid. The physiological and biochemical characteristics, low DNA-DNA relatedness values, and taxonomic analysis allowed the differentiation of strain Gsoil 188T from the other recognized species of the genus Brevibacterium. Therefore, strain Gsoil 188T represents a novel species of the genus Brevibacterium, for which the name Brevibacterium anseongense sp. nov. is proposed, with the type strain Gsoil 188T (= KACC 19439T = LMG 30331T).  相似文献   
16.
Ecological speciation via host-shifting is often invoked as a mechanism for insect diversification, but the relative importance of this process is poorly understood. The shift of Rhagoletis pomonella in the 1850s from the native downy hawthorn, Crataegus mollis, to introduced apple, Malus pumila, is a classic example of sympatric host race formation, a hypothesized early stage of ecological speciation. The accidental human-mediated introduction of R. pomonella into the Pacific Northwest (PNW) in the late 1970s allows us to investigate how novel ecological opportunities may trigger divergent adaptation and host race formation on a rapid timescale. Since the introduction, the fly has spread in the PNW, where in addition to apple, it now infests native black hawthorn, Crataegus douglasii, and introduced ornamental hawthorn, Crataegus monogyna. We use this “natural experiment” to test for genetic differentiation among apple, black, and ornamental hawthorn flies co-occurring at three sympatric sites. We report evidence that populations of all three host-associations are genetically differentiated at the local level, indicating that partial reproductive isolation has evolved in this novel habitat. Our results suggest that conditions suitable for initiating host-associated divergence may be common in nature, allowing for the rapid evolution of new host races when ecological opportunity arises.  相似文献   
17.

Background  

Helicoverpa armigera and H. zea are amongst the most significant polyphagous pest lepidopteran species in the Old and New Worlds respectively. Separation of H. armigera and H. zea is difficult and is usually only achieved through morphological differences in the genitalia. They are capable of interbreeding to produce fertile offspring. The single species status of H. armigera has been doubted, due to its wide distribution and plant host range across the Old World. This study explores the global genetic diversity of H. armigera and its evolutionary relationship to H zea.  相似文献   
18.
The development of blended collagen and glycosaminoglycan (GAG) scaffolds can potentially be used in many soft tissue engineering applications since the scaffolds mimic the structure and biological function of native extracellular matrix (ECM). In this study, we were able to obtain novel nanofibrous collagen-GAG scaffolds by electrospinning collagen blended with chondroitin sulfate (CS), a widely used GAG, in a mixed solvent of trifluoroethanol and water. The electrospun collagen-GAG scaffold with 4% CS (COLL-CS-04) exhibited a uniform fiber structure with nanoscale diameters. A second collagen-GAG scaffold with 10% CS consisted of smaller diameter fibers but exhibited a broader diameter distribution due to the different solution properties in comparison with COLL-CS-04. After cross-linking with glutaraldehyde vapor, the collagen-GAG scaffolds became more biostable and were resistant to collagenase degradation. This is evidently a more favorable environment allowing increased proliferation of rabbit conjunctiva fibroblast on the scaffolds. Incorporation of CS into collagen nanofibers without cross-linking did not increase the biostability but still promoted cell growth. The potential of applying the nanoscale collagen-GAG scaffold in tissue engineering is significant since the nanodimension fibers made of natural ECM mimic closely the native ECM found in the human body. The high surface area characteristic of this scaffold may maximize cell-ECM interaction and promote tissue regeneration faster than other conventional scaffolds.  相似文献   
19.
These studies test whether allograft rejection can be blocked by interference with leukocyte adhesion, using a murine IgG2a mAb (R6.5) reactive with monkey ICAM-1 (CD54). In 16 Cynomolgus renal allograft recipients, R6.5 was administered prophylactically as the sole immunosuppressive agent for 12 days (0.01 to 2 mg/kg/day). Survival in 14 recipients with technically successful grafts was significantly prolonged (24.2 +/- 2.4 vs 9.2 +/- 0.6 days for controls; p less than 0.001). Intercellular adhesion molecule-1 (CD54) (ICAM-1) was expressed on vascular endothelium in the kidney and other organs in the monkey in a pattern similar to that in humans. During cellular rejection in controls, ICAM-1 expression increased on endothelial cells, infiltrating mononuclear leukocytes and tubular cells. Biopsies during R6.5 administration showed decreased T cell infiltration (CD2, CD8, CD4) compared with controls and decreased arterial endothelial inflammation. No changes occurred in circulating T cells, aside from variable coating with mIgG. In six of eight other recipients R6.5 administration (0.5 to 2 mg/kg/day for 10 days) reversed preexisting rejection that resulted from taper of Cyclosporine to subtherapeutic levels. Responding grafts showed decreased edema and hemorrhage but no consistent change in the infiltrate. At 1 h after the first dose, mouse IgG deposited primarily on the graft vascular endothelium without any change in the inflammatory infiltrate. Mouse IgG also deposited on the endothelium of normal organs without eliciting an inflammatory response and was cleared from the endothelium within 4 days. Inasmuch as the principal site of binding was the vascular endothelium, we hypothesize that the antibody blocks adhesion to graft ICAM-1 molecules on the vessels. Anti-ICAM-1 also binds to recipient cells and may interfere with Ag presentation and/or T cell interactions. Whatever the mechanism(s), these studies indicate that an anti-ICAM-1 antibody inhibits T cell mediated injury in vivo, and that ICAM-1 is a critical molecule in the pathogenesis of allograft rejection.  相似文献   
20.
Spider webs are made of silk, the properties of which ensure remarkable efficiency at capturing prey. However, remaining on, or near, the web exposes the resident spiders to many potential predators, such as ants. Surprisingly, ants are rarely reported foraging on the webs of orb-weaving spiders, despite the formidable capacity of ants to subdue prey and repel enemies, the diversity and abundance of orb-web spiders, and the nutritional value of the web and resident spider. We explain this paradox by reporting a novel property of the silk produced by the orb-web spider Nephila antipodiana (Walckenaer). These spiders deposit on the silk a pyrrolidine alkaloid (2-pyrrolidinone) that provides protection from ant invasion. Furthermore, the ontogenetic change in the production of 2-pyrrolidinone suggests that this compound represents an adaptive response to the threat of natural enemies, rather than a simple by-product of silk synthesis: while 2-pyrrolidinone occurs on the silk threads produced by adult and large juvenile spiders, it is absent on threads produced by small juvenile spiders, whose threads are sufficiently thin to be inaccessible to ants.  相似文献   
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