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91.
We evaluated the effects of Leishmania spp infection on several
population parameters of Lutzomyia longipalpis sensu lato
andLutzomyia pseudolongipalpis, vectors of visceral leishmaniasis
in Venezuela, under experimental conditions during the first post-feeding period.
Females of both species were allowed to feed and engorge on a suspension of fresh
washed human red blood cells in foetal calf serum. These blood cells were either
non-infected or infected with one of the fourLeishmania spp strains
and were offered through a chicken skin membrane. The longevity, life expectancy and
the fecundity of uninfected flies were similar in both species, but the fertility was
significantly lower in uninfected Lu. longipalpis females. In all
cases, the infection of Lu. longipalpis and Lu.
pseudolongipalpis by the Leishmania strains resulted in
significant detrimental effects, which exerted a fitness cost expressed by reduced
survival and life expectancy, as well as decreased fertility and fecundity compared
with the control groups. Nevertheless, differences in these parameters were observed
between these vector species depending on whether they were infected with the
autochthonous Venezuelan Leishmania infantum strain (NESA) or the
Brazilian reference strain (PP75). The experimental data obtained agree with field
data on the natural infection of these vector species and the significance of this
scenario is discussed. 相似文献
92.
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94.
Kisspeptin1 modulates odorant‐evoked fear response via two serotonin receptor subtypes (5‐HT1A and 5‐HT2) in zebrafish 下载免费PDF全文
Kiss1, a neuropeptide predominantly expressed in the habenula, modulates the serotonin (5‐HT) system to decrease odorant cue [alarm substance (AS)]‐evoked fear behaviour in the zebrafish. The purpose of this study was to assess the interaction of Kiss1 with the 5‐HT system as well as to determine the involvement of the 5‐HT receptor subtypes in AS‐evoked fear. We utilized 0. 28 mg/kg WAY 100635 (WAY), a selective 5‐HT1A receptor antagonist, to observe the effects of Kiss1 administration on AS‐evoked fear. We found WAY significantly inhibited the anxiolytic effects of Kiss1 (p < 0.001) with an exception of freezing behaviour. Based on this, we utilized 92.79 mg/kg methysergide, a 5‐HT1 and 5‐HT2 receptor antagonist, and found that methysergide significantly blocked the anxiolytic effects of Kiss1 in the presence of the AS (p < 0.001). From this, we conclude that Kiss1 modulates AS‐evoked fear responses mediated by the 5‐HT1A and 5‐HT2 receptors.
95.
Effect of Pre‐ and Post–Combined Multidoses of Epigallocatechin Gallate and Coenzyme Q10 on Cisplatin‐Induced Oxidative Stress in Rat Kidney 下载免费PDF全文
Sabiha Fatima Noura Al‐Mohaimeed Sadia Arjumand Naheed Banu Noura Al‐Jameil Yazeed Al‐Shaikh 《Journal of biochemical and molecular toxicology》2015,29(2):91-97
The nephroprotective effect of coenzyme Q10 and epigallocatechin gallate was investigated in rats with acute renal injury induced by a single nephrotoxic dose of cisplatin. Two days prior to cisplatin administration, epigallocatechin gallate and coenzyme Q10 alone and in four different combinations were given for 6 days. The treatment with antioxidants significantly protected the cisplatin‐induced increase in the levels of blood urea nitrogen and serum creatinine. Both the antioxidants alone or in different combinations significantly compensated the increased malondialdehyde and reduced glutathione levels. Moreover, the decrease in the activities of superoxide dismutase, catalase, and glutathione peroxidase and the concentration of selenium, zinc, and copper ions were significantly attenuated in renal tissue. In conclusion, epigallocatechin gallate and coenzyme Q10 are equally effective against cisplatin‐induced nephrotoxicity, whereas the intervention by combining these two antioxidants was found to be highly effective at low doses in attenuating oxidative stress in rat kidney. 相似文献
96.
Sibhghatulla Shaikh Jamale Fatima Shazi Shakil Syed Mohd. Danish Rizvi Mohammad Amjad Kamal 《Saudi Journal of Biological Sciences》2015,22(1):62-64
Resistance to broad-spectrum beta-lactams, mediated by extended-spectrum beta-lactamase enzymes (ESBL), is an increasing problem worldwide. The present study was undertaken to determine the incidence of ESBL-production among the clinical isolates of Pseudomonas aeruginosa and their susceptibility to selected antimicrobials. A total of one eighty-seven clinical specimens were tested for the presence of ESBL production using the double-disc synergy test. Of these, 25.13% (n = 47) isolates of P. aeruginosa were observed as ESBL positive. The maximum number of ESBL-producing strains were found in sputum (41.67%; n = 24) followed by pus (28.36%; n = 19), cerebrospinal fluid and other body fluids (21.74%; n = 5), urine (20.45%; n = 9) and blood (13.79%; n = 4). ESBL producing isolates exhibited co-resistance to an array of antibiotics tested. Imipenem and meropenem can be suggested as the drugs of choice in our study. 相似文献
97.
Antonio Dobon Pilar Cordero Fatima Kreft Søren R. Østergaard Helle Antvorskov Mats Robertsson Maria Smolander Mercedes Hortal 《The International Journal of Life Cycle Assessment》2011,16(6):537-547
Purpose
This paper is the second part of a two-paper series dealing with the sustainability evaluation of a new communicative packaging concept. The communicative packaging concept includes a device that allows changing the expiry date of the product as function of temperature during transport and storage: a flexible best-before-date (FBBD). Such device was analysed in a consumer unit consisting of a nanoclay-based polylactic acid tray filled with pork chops. 相似文献98.
Nai-Ying YangCarlos Fernandez Melanie Richter Zhan Xiao Fatima ValenciaDavid A. Tice Elena B. Pasquale 《Cellular signalling》2011,23(1):201-212
Receptor tyrosine kinases of the Eph family play multiple roles in the physiological regulation of tissue homeostasis and in the pathogenesis of various diseases, including cancer. The EphA2 receptor is highly expressed in most cancer cell types, where it has disparate activities that are not well understood. It has been reported that interplay of EphA2 with oncogenic signaling pathways promotes cancer cell malignancy independently of ephrin ligand binding and receptor kinase activity. In contrast, stimulation of EphA2 signaling with ephrin-A ligands can suppress malignancy by inhibiting the Ras-MAP kinase pathway, integrin-mediated adhesion, and epithelial to mesenchymal transition. Here we show that ephrin-A1 ligand-dependent activation of EphA2 decreases the growth of PC3 prostate cancer cells and profoundly inhibits the Akt-mTORC1 pathway, which is hyperactivated due to loss of the PTEN tumor suppressor. Our results do not implicate changes in the activity of Akt upstream regulators (such as Ras family GTPases, PI3 kinase, integrins, or the Ship2 lipid phosphatase) in the observed loss of Akt T308 and S473 phosphorylation downstream of EphA2. Indeed, EphA2 can inhibit Akt phosphorylation induced by oncogenic mutations of not only PTEN but also PI3 kinase. Furthermore, it can decrease the hyperphosphorylation induced by constitutive membrane-targeting of Akt. Our data suggest a novel signaling mechanism whereby EphA2 inactivates the Akt-mTORC1 oncogenic pathway through Akt dephosphorylation mediated by a serine/threonine phosphatase. Ephrin-A1-induced Akt dephosphorylation was observed not only in PC3 prostate cancer cells but also in other cancer cell types. Thus, activation of EphA2 signaling represents a possible new avenue for anti-cancer therapies that exploit the remarkable ability of this receptor to counteract multiple oncogenic signaling pathways. 相似文献
99.
100.
Mesenchymal stromal cells (MSC) can be isolated from adult tissues and induced to differentiate into skeletal cells, such as osteoblasts, chondrocytes and adipocytes. Consequently, ex vivo MSC are valuable systems for studying the mechanisms that control tissue-context lineage commitment and may offer broad therapeutic applications in the orthopedic theater and beyond. To date, most of these studies have used MSC grown on two-dimensional (2-D) plastic surfaces. The use of three-dimensional (3-D) in vitro growth techniques for MSC may accelerate these areas of research by providing a more representative 'in vivo-like' environment, where cells interact with each other and their cellular products, rather than a plastic surface. We introduce some of the techniques used for 3-D in vitro cultures and how they relate to the MSC field. We will present evidence of how MSC grown as 3-D spheroids not only permits appropriate MSC-like behavior, but appears to promote their stem-cell attributes and therapeutic benefit in applications ranging from regenerative medicine to anti-inflammatory treatments and cancer therapy. 3-D culture techniques also allow de/reconstruction of the specialized in vivo niche of the tissue-resident stem cell where microenvironmental influences can be recognized. 相似文献