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Depletion of total antioxidant capacity in type 2 diabetes   总被引:4,自引:0,他引:4  
The purpose of the study was to examine the relationship between antioxidant depletion, glycemic control, and development of chronic complications in a controlled population of type 2 diabetic patients. Fifty age-matched type 2 diabetic patients receiving sulfonylureas but not insulin treatment were screened and assigned to two groups based on the presence or absence of proteinuria. A third group of normal subjects without diabetes were also enrolled in the study. All subjects in the three groups were Egyptians who were matched for body weight, and the two diabetic groups were also age-matched. Plasma glucose and fructosamine levels were higher in the two groups of diabetic patients versus the control group, but lipid peroxide levels were higher only in the patients with proteinuria. Compared with the control group, the total antioxidant capacity was depleted in the two diabetic groups, but the depletion was more severe in patients with proteinuria. Thus, the mean Trolox equivalent antioxidant capacity (TEAC) of the control group was 2.7+/-0.45, versus 1.7+/-0.5 (P < .001) in the patients without proteinuria. Furthermore, the TEAC measured in patients with proteinuria, who also had more diabetic complications, was lower (1.4+/-0.5, P < .001) than the TEAC in patients without urinary protein. In conclusion, a depletion of the total antioxidant capacity is associated with a higher incidence of diabetic complications.  相似文献   
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Interleukin 8 (IL-8), is a proinflammatory chemokine, has been reported to have angiogenic activity and to be responsible for tumor-associated angiogenesis in several cancers. In this study, we aimed to study the (IL-8) gene polymorphism in relation with risk development of non small cell lung cancer in Tunisian patient. Two single nucleotide polymorphisms (−251T/A [rs4073], +781C/T [rs2227306]) of the IL-8 gene were screened in 170 patients with NSCLC and 225 healthy controls by PCR–RFLP.  相似文献   
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Although maternal postpartum mental health has been extensively studied, rather little is known regarding the factors that may facilitate psychological growth following childbirth. The present study set forth to examine various pre-birth, birth, and post-birth correlates of overall psychological growth and growth domains in postpartum women, assessed within the first months following childbirth. A sample of 428 women completed self-report measures pertaining to psychological growth, mental health, maternal attachment, and childbirth characteristics. We found that the majority of women reported psychological growth following childbirth, with those experiencing stressors in childbirth reporting the highest levels of appreciation for life. In regression analyses, postpartum factors were significantly associated with overall growth and growth domains, taking into account other factors. The more the childbirth was perceived as central to the mothers’ identity and the better the maternal attachment was to the child, the higher levels of growth. Growth was also negatively related to endorsement of childbirth PTSD. Background factors, such as maternal age, education, and prior mental health, were associated with specific growth domains, although the association was small and there was no association with overall growth. Post-birth factors are important in ensuing psychological growth in the first months following birth. Attention to opportunities of growth following childbirth is warranted in clinical care, in particular following traumatic childbirth.

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The distribution of cone photoreceptor subtypes (important for color vision and vision quality) varies widely in different carnivore species, but there have been limited studies on bear (ursid) cone distribution. A previous behavioral study suggests that American black bears (Ursus americanus) are dichromatic, indicating that they possess two cone subtypes, although the retinal distribution of cones is unknown. The purpose of this study was to examine the subtype and topography of cones in American black bear retinas to further predict the nature of their color vision and image resolution. We studied 10 eyes from seven individual legally hunted black bears in northeastern North Carolina. Cryosections and retinal wholemounts were labeled using antibodies targeting two cone opsin subtypes: long/medium (L/M) wavelength sensitive and short (S) wavelength sensitive. Cones in fluorescent microscopy images were counted and density maps were created for retinal wholemounts. The black bear retina contains both cone subtypes and L/M cones outnumber S cones by at least 3:1, a finding confirmed in retinal frozen sections. There are higher concentrations of S cones present than typically seen in other carnivores with some evidence for co-expression of L/M and S cones. A cone-dense area centralis is present dorsotemporal to the optic nerve, similar to other carnivores. These results confirm that American black bears are predicted to have a dichromatic vision with high acuity indicated by the presence of a dorsotemporally located area centralis.  相似文献   
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This article presents the annealing effect on the structural, elastic, thermodynamic, optical, magnetic, and electric properties of Ni0.6Zn0.4Fe1.5Al0.5O4 (NZFAO) nanoparticles (NPs). The samples were successfully synthesized by the sol–gel method followed by annealing of the as-synthesized at 600, 800, 900, 1050, and 1200 °C. This approach yielded the formation of a highly crystalline structure with crystallite size ranging from 17 nm to 40 nm. X-ray diffraction (XRD), scanning electron microscopy (SEM) techniques, as well as energy disperse spectroscopy (EDS), Fourier transform infrared (FTIR) and Raman spectroscopy, were used in order to determine the structural and morphological properties of the prepared samples. Rietveld XRD refinement reveals that Ni–Zn–Al ferrite nanoparticles crystallize in inverse cubic (Fd3̄m) spinel structure. Using FTIR spectra, the elastic and thermodynamic properties were estimated. It was observed that the particle size had a pronounced effect on elastic and thermodynamic properties. Magnetic measurements were performed up to 700 K. The prepared ferrite samples present the highest Curie temperature, which decreases with increasing particle size and which is consistent with finite-size scaling. The thickness of the surface shell of about 1 nm was estimated from size-dependent magnetization measurements using the core–shell model. Besides, spin resonance, magnetostriction, temperature coefficient of resistance (TCR), and electrical resistivity properties have been scientifically studied and appear to be different according to their size. The optical properties of synthesized NZFAO nanoparticles were investigated, and the differences caused by the particle sizes are discussed on the basis of the phonon confinement effect. This effect was also inspected by the Raman analysis. Tuning of the physical properties suggests that the Ni–Zn–Al ferrite samples may be promising for multifunctional diverse applications.

This article presents the annealing effect on the structural, elastic, thermodynamic, optical, magnetic, and electric properties of Ni0.6Zn0.4Fe1.5Al0.5O4 (NZFAO) nanoparticles (NPs).  相似文献   
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Activation of the Na+-K+-2Cl-cotransporter (NKCC2) and the Na+-Cl-cotransporter (NCC) by vasopressin includes their phosphorylation at defined, conserved N-terminal threonine and serine residues, but the kinase pathways that mediate this action of vasopressin are not well understood. Two homologous Ste20-like kinases, SPS-related proline/alanine-rich kinase (SPAK) and oxidative stress responsive kinase (OSR1), can phosphorylate the cotransporters directly. In this process, a full-length SPAK variant and OSR1 interact with a truncated SPAK variant, which has inhibitory effects. Here, we tested whether SPAK is an essential component of the vasopressin stimulatory pathway. We administered desmopressin, a V2 receptor–specific agonist, to wild-type mice, SPAK-deficient mice, and vasopressin-deficient rats. Desmopressin induced regulatory changes in SPAK variants, but not in OSR1 to the same degree, and activated NKCC2 and NCC. Furthermore, desmopressin modulated both the full-length and truncated SPAK variants to interact with and phosphorylate NKCC2, whereas only full-length SPAK promoted the activation of NCC. In summary, these results suggest that SPAK mediates the effect of vasopressin on sodium reabsorption along the distal nephron.The furosemide-sensitive Na+-K+-2Cl-cotransporter (NKCC2) of the thick ascending limb (TAL) and the thiazide-sensitive Na+-Cl-cotransporter (NCC) of the distal convoluted tubule (DCT) are key regulators of renal salt handling and therefore participate importantly in BP and extracellular fluid volume homeostasis.1 Loss-of-function mutants in the SLC12A1/ A3 genes encoding NKCC2 and NCC cause salt-losing hypotension and hypokalemic alkalosis in Bartter’s and Gitelman’s syndromes,2,3 whereas their overactivity may contribute to essential hypertension.4,5 Recently, attention has been focused on the two closely related STE20-like kinases, SPS-related proline/alanine-rich kinase (SPAK) and oxidative stress responsive kinase 1 (OSR1), which can phosphorylate NKCC2 and NCC at their N-terminal conserved threonine or serine residues (T96, T101, and T114 of mouse NKCC2 and T53, T58, and S71 of mouse NCC) and thereby activate the transporters.68 Despite the high homology between SPAK and OSR1 and their overlapping renal expression patterns, distinct roles along the nephron have been suggested based on data from SPAK-deficient and kidney-specific OSR1-deficient mice: deletion of SPAK primarily impairs the function of NCC, whereas deletion of OSR1 negatively affects NKCC2.911 The complex functional properties of a WNK-SPAK/OSR1-N(K)CC interaction cascade are currently being defined.12 Recently, arginine vasopressin (AVP), signaling via the V2 receptor (V2R), has been identified as an efficient activator of both cotransporters, affecting their luminal trafficking and phosphorylation.1318 Because plasma AVP levels may vary not only with the sleep-wake cycle or long-term physiologic challenges, but also with pulsatile changes over the short term, distinct, time-dependent responses may occur.19 SPAK and OSR1 are well placed to regulate distal NaCl reabsorption in response to AVP. Here we tested the role of SPAK in AVP-induced activation of NKCC2 and NCC, acutely and during long-term treatment. The results suggest that SPAK is an essential kinase that modulates distal nephron function in response to AVP stimulation.  相似文献   
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