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1.
Excessive intake of essential elements agitates elemental homeostasis resulting in their heterogeneous distribution. Distraction of these elements in central nervous system (CNS) have been demonstrated in many neurological disorders, which are vital in generating free radicals, causing oxidative stress, and contributing to neuronal maladies. The developing CNS is highly vulnerable to environmental agents, including fluoride. Fluorosis is one such disorder ensued from excessive consumption of fluoride containing water and/or foods that poses a greater threat to the life. Present study offers perturbations caused by fluoride toxicity on the level of biometal and antioxidant homeostasis and their interactions. Pregnant Wistar rats were exposed to 100- and 200-ppm fluoride (F) in drinking water and controls with tap water. The pups born to them were used for the study. On 21st postnatal day, the concentration of fluoride, biometals, and oxidative stress markers were determined in discrete regions of CNS. The levels of fluoride, copper, and iron increased whereas manganese and zinc were decreased considerably. Among antioxidant enzymes, catalase, superoxide dismutase, and glutathione peroxidase were decreased and lipid peroxidation was increased with regional alterations. The correlation coefficient values among oxidative stress markers and biometals were either positive or negative and showed less significance during correlation. The results confirm that the fluoride provoked oxidative stress and biometal deformations are synergistic that successively governs the neuronal damage and developing CNS no longer prevents exacerbations of fluoride.  相似文献   
2.
Two major problems associated with biofouling studies are the lack of broad scale testing and failure to use consistent standards among different assays or studies. To address these issues the activity of two biologically active natural products, elatol and deschloroelatol, isolated from the marine red alga Laurencia rigida, and three commonly used biocides, Nopcocide N-96?, Irgarol 1051? and Sea-Nine 211?, was compared, in a broad spectrum of bioassays. The activity of the different compounds varied substantially among different bioassay tests. Elatol and deschloroelatol had a narrow range of activity with strongest effects against invertebrate larvae. Both compounds were highly toxic. However, neither compound had strong activity against marine bacteria or the common epiphyte Ulva lactuca. Irgarol 1051 also had a narrow range of activity, only affecting algal settlement strongly. Nopcocide N-96 and Sea-Nine 211 had moderate to strong activity across the spectrum of bioassays, viz. growth of marine bacteria (Vibrio fischeri, Serratia sp.), inhibition of settlement of macroalgae (Ulva lactuca), toxicity (Balanus amphitrite), and inhibition of settlement of invertebrate larvae (Balanus amphitrite, Bugula neritina). Based on the results it is proposed that Sea-Nine 211, because of its broad spectrum activity, be used as a standard for comparative assessments of the antifouling activity of marine natural products and analogues.  相似文献   
3.
Birthday parties are a relatively new occurrence at Yuendumu, a Warlpiri settlement in central Australia. By focusing on the food prepared and consumed at these parties, I examine the ritualised Warlpiri and non‐Warlpiri elements of these events, with a particular view to Warlpiri women's creativity in shaping and re‐shaping them. I contrast birthday party food from everyday staple foods and so‐called ‘bush tucker’, and analyse these different food types in regard to generational differentiation. Lastly, the role of the anthropologist in shaping birthday parties as well as in writing about them is scrutinised.  相似文献   
4.

Iron is an essential trace element involved in oxidation–reduction reactions, oxygen transport and storage, and energy metabolism. Iron in excess can be toxic for cells, since iron produces reactive oxygen species and is important for survival of pathogenic microbes. There is a fine-tuning in the regulation of serum iron levels, determined by intestinal absorption, macrophage iron recycling, and mobilization of hepatocyte stores versus iron utilization, primarily by erythroid cells in the bone marrow. Hepcidin is the major regulatory hormone of systemic iron homeostasis and is upregulated during inflammation. Hepcidin metabolism is altered in chronic kidney disease. Ferroportin is an iron export protein and mediates iron release into the circulation from duodenal enterocytes, splenic reticuloendothelial macrophages, and hepatocytes. Systemic iron homeostasis is controlled by the hepcidin–ferroportin axis at the sites of iron entry into the circulation. Hepcidin binds to ferroportin, induces its internalization and intracellular degradation, and thus inhibits iron absorption from enterocytes, and iron release from macrophages and hepatocytes. Recent data suggest that hepcidin, by slowing or preventing the mobilization of iron from macrophages, may promote atherosclerosis and may be associated with increased cardiovascular disease risk. This article reviews the current data regarding the molecular and cellular pathways of systemic and autocrine hepcidin production and seeks the answer to the question whether changes in hepcidin translate into clinical outcomes of all-cause and cardiovascular mortality, and cardiovascular and renal end-points.

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5.
This study illustrated the immunohistochemical distribution of androgen and vitamin D receptors of epididymis in 20 sexually mature ram (Rahmani breed) with average age ranged from (2_4) years and average weight ranged from (50_65kg). Androgen receptor was localized in the cytoplasm of both ciliated and non ciliated cells of efferent ductules, besides the principal cells via the entire epididymal duct. The principal cells of both corpus and proximal cauda epididymis showed the highest immunoreactivity to androgen receptors. Furthermore, vitamin D receptor was localized in the cytoplasm of all epithelium of the efferent ductules besides principal cells of all epididymal regions, however the immunoreaction was significantly higher in the efferent ductules, distal caput and distal cauda epididymis. In conclusion, these results suggest that the function of ram epididymis is regulated by both androgen and Vitamin D.  相似文献   
6.
Sleeping leaves those asleep ‘blind’ and hence oblivious to potential or real danger. Such dangers are heightened further and more feared at night, the main time for sleep. In this article, I link ideas about sleep and nighttime social practices with questions about vision. My aim is to tease out some of the meanings implied in cross‐culturally distinct solutions to the protection of sleepers at night. I proceed by contrasting ethnographic data from the remote Aboriginal settlement of Yuendumu, Northern Territory, with select elements of the cultural history of Euro‐American sleep. Through ethnographic vignettes, I illuminate how people at Yuendumu commonly arrange themselves in yunta, or rows of sleepers, at night, and how some sleepers awake regularly during the night to ensure the others’ safety. I contrast this with Euro‐American ways of providing a sense of safety to the sleeper through practices of domestic fortification. My comparison revolves around the notion of sight, which in the Euro‐American West is clearly linked to ideas of knowledge, and at Yuendumu, as I demonstrate, imbued with a sense of care. I conclude by relating the gained insights to participant observation as anthropological method.  相似文献   
7.
Evidence is presented to show that self-sustained oscillations of purely hemodynamical origin are possible in some arcade-type microvascular networks supplied with steady boundary conditions, but that in others the oscillations disappear with sufficient reduction of the time step Δt, showing them to be numerical artefacts. In an attempt to elucidate the mechanisms involved in the onset of fluctuations, we proceed to perform a linear stability analysis for the convective model of Kiani et al. (Microvasc. Res. 45:219–232, 1993; Am. J. Physiol. 266(35):H1822–H1828, 1994), and show that this leads via a system of delay differential equations to a nonlinear eigenvalue problem. This result generalises the characteristic equation obtained by Carr et al. (Ann. Biomed. Eng. 33:764–771, 2005) and Geddes et al. (SIAM J. Appl. Dyn. Syst. 6(4):694–727, 2007) who solved a special case in a two node network. An implicit numerical method is proposed for the computation of blood flows in networks using the convective model. In a moderate size subnetwork of one of the networks chosen by Kiani et al. (Am. J. Physiol. 266(35):H1822–H1828, 1994), the topology, vessel lengths, and diameters of which were based on microvascular networks in the rat mesentery, we compare results generated using the original explicit numerical method of Kiani et al. (Am. J. Physiol. 266(35):H1822–H1828, 1994) with those from our implicit scheme. From the linear stability theory, a critical value D RBC,crit of a red blood cell diameter parameter D RBC in the plasma skimming model of Fenton et al. (Pflügers Arch. 403:396–401, 1985b) is identified for the onset of oscillations about steady state and both the explicit and implicit methods are used to calculate the inflow hematocrit solutions in all vessels of the subnetwork at the critical parameter value, subject to perturbed initial conditions. The results of the implicit method are demonstrated to be in excellent and superior agreement with the predictions of the linear analysis in this case. For values of D RBC slightly larger than D RBC,crit the bifurcating periodic solutions calculated using either the explicit or implicit schemes are characteristic of those of a supercritical Hopf bifurcation and the graphs of D RBC vs. oscillation amplitude would seem to converge as Δt→0.  相似文献   
8.
A full-length cDNA encoding a putative aspartic acid protease (AcAP1) was isolated for the first time from the flesh of pineapple (Ananas comosus) fruit. The deduced sequence of AcAP1 showed all the common features of a typical plant aspartic protease phytepsin precursor. Analysis of AcAP1 gene expression under postharvest chilling treatment in two pineapple varieties differing in their resistance to blackheart development revealed opposite trends. The resistant variety showed an up-regulation of AcAP1 precursor gene expression whereas the susceptible showed a down-regulation in response to postharvest chilling treatment. The same trend was observed regarding specific AP enzyme activity in both varieties. Taken together our results support the involvement of AcAP1 in postharvest chilling stress resistance in pineapple fruits.  相似文献   
9.
The perinucleolar compartment (PNC) is a subnuclear stucture forming predominantly in cancer cells; its prevalence positively correlates with metastatic capacity. Although several RNA-binding proteins have been characterized in PNC, the molecular function of this compartment remains unclear. Here we demonstrate that the cyclin–dependent kinase 13 (CDK13) is a newly identified constituent of PNC. CDK13 is a kinase involved in the regulation of gene expression and whose overexpression was found to alter pre-mRNA processing. In this study we show that CDK13 is enriched in PNC and co-localizes all along the cell cycle with the PNC component PTB. In contrast, neither the cyclins K and L, known to associate with CDK13, nor the potential kinase substrates accumulate in PNC. We further show that CDK13 overexpression increases PNC prevalence suggesting that CDK13 may be determinant for PNC formation. This result linked to the finding that CDK13 gene is amplified in different types of cancer indicate that this kinase can contribute to cancer development in human.  相似文献   
10.
Spermatogenesis is a complex and highly regulated process by which spermatogonial stem cells differentiate into spermatozoa. To better understand the molecular mechanisms of the process, the Cre/loxP system has been widely utilized for conditional gene knockout in mice. In this study, we generated a transgenic mouse line that expresses Cre recombinase under the control of the 2.5 kbp of the Prolactin family 3, subfamily b, member 1 (Prl3b1) gene promoter (Prl3b1‐cre). Prl3b1 was initially reported to code for placental lactogen 2 (PL‐2) protein in placenta along with increased expression toward the end of pregnancy. PL‐2 was found to be expressed in germ cells in the testis, especially in spermatocytes. To analyze the specificity and efficiency of Cre recombinase activity in Prl3b1‐cre mice, the mice were mated with reporter R26GRR mice, which express GFP ubiquitously before and tdsRed exclusively after Cre recombination. The systemic examination of Prl3b1‐cre;R26GRR mice revealed that tdsRed‐positive cells were detected only in the testis and epididymis. Fluorescence imaging of Prl3b1‐cre;R26GRR testes suggested that Cre‐mediated recombination took place in the germ cells with approximately 74% efficiency determined by in vitro fertilization. In conclusion, our results suggest that the Prl3b1cre mice line provides a unique resource to understand testicular germ‐cell development. genesis 54:389–397, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
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