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81.
Naveen Kumar Kadri Goutam Sahana Carole Charlier Terhi Iso-Touru Bernt Guldbrandtsen Latifa Karim Ulrik Sander Nielsen Frank Panitz Gert Pedersen Aamand Nina Schulman Michel Georges Johanna Vilkki Mogens Sand? Lund Tom Druet 《PLoS genetics》2014,10(1)
In dairy cattle, the widespread use of artificial insemination has resulted in increased selection intensity, which has led to spectacular increase in productivity. However, cow fertility has concomitantly severely declined. It is generally assumed that this reduction is primarily due to the negative energy balance of high-producing cows at the peak of lactation. We herein describe the fine-mapping of a major fertility QTL in Nordic Red cattle, and identify a 660-kb deletion encompassing four genes as the causative variant. We show that the deletion is a recessive embryonically lethal mutation. This probably results from the loss of RNASEH2B, which is known to cause embryonic death in mice. Despite its dramatic effect on fertility, 13%, 23% and 32% of the animals carry the deletion in Danish, Swedish and Finnish Red Cattle, respectively. To explain this, we searched for favorable effects on other traits and found that the deletion has strong positive effects on milk yield. This study demonstrates that embryonic lethal mutations account for a non-negligible fraction of the decline in fertility of domestic cattle, and that associated positive effects on milk yield may account for part of the negative genetic correlation. Our study adds to the evidence that structural variants contribute to animal phenotypic variation, and that balancing selection might be more common in livestock species than previously appreciated. 相似文献
82.
Heba M. Mahdy Mohamed R. Mohamed Manal A. Emam Amr M. Karim Ashraf B. Abdel-Naim Amani E. Khalifa 《Neurochemical research》2014,39(2):321-332
Puerarin (daidzein-8-C-glucoside), a major isoflavone glycoside purified from Pueraria lobata, is well reported to have a neuroprotective effect primarily by the antioxidant mechanisms. This investigation was designed to evaluate the efficacy of Puerarin (Pur) to offset 3-nitropropionic acid (3-NP) induced neurotoxicity. Male Wistar strain rats were given 3-NP (20 mg/kg, s.c.) over five consecutive days, whereas Pur (200 mg/kg, i.p.) was administrated 30 min before 3-NP. Rats treated with 3-NP exhibited significant weight loss, reduction of the prepulse inhibition, locomotor hypoactivity and hypothermia. The striata, hippocampi and cortices of the 3-NP treated rats showed abnormal levels of neurotransmitters, oxidative damage and characteristic histopathological lesions. Treatment with Pur ahead of 3-NP, significantly prevented weight loss, PPI deficit, locomotor hypoactivity and hypothermia. Pur treatment blocked the 3-NP-induced neurotransmitters abnormalities (GABA, DA, 5-HT and NE), and normalized the oxidative stress biomarkers (lipid peroxidation, reduced glutathione, glutathione peroxidase). Histopathological examination further affirmed Pur’s neuroprotective effect against 3-NP-induced neurotoxicity. In conclusion, Pur protected the brain tissues from 3-NP induced neurotoxicity primarily by its neuromodulation and antioxidant effect. 相似文献
83.
Bichara M Attmane-Elakeb A Brown D Essig M Karim Z Muffat-Joly M Micheli L Eude-Le Parco I Cluzeaud F Peuchmaur M Bonvalet JP Poirier F Farman N 《Glycobiology》2006,16(1):36-45
Galectin 3 belongs to a family of glycoconjugate-binding proteinsthat participate in cellular homeostasis by modulating cellgrowth, adhesion, and signaling. We studied adult galectin 3null mutant (Gal 3/) and wild-type (WT) mice togain insights into the role of galectin 3 in the kidney. Byimmunofluorescence, galectin 3 was found in collecting duct(CD) principal and intercalated cells in some regions of thekidney, as well as in the thick ascending limbs at lower levels.Compared to WT mice, Gal 3/ mice had ~11% fewerglomeruli (p < 0.04), associated with kidney hypertrophy(p < 0.006). In clearance experiments, urinary chloride excretionwas found to be higher in Gal 3/ than in WT mice(p < 0.04), but there was no difference in urinary bicarbonateexcretion, in glomerular filtration, or urinary flow rates.Under chronic low sodium diet, Gal 3/ mice hadlower extracellular fluid (ECF) volume than WT mice (p <0.05). Plasma aldosterone concentration was higher in Gal 3/than in WT mice (p < 0.04), which probably caused the observedincrease in -epithelial sodium channel (-ENaC) protein abundancein the mutant mice (p < 0.001). Chronic high sodium dietresulted paradoxically in lower blood pressure (p < 0.01)in Gal 3/ than in WT. We conclude that Gal 3/mice have mild renal chloride loss, which causes chronic ECFvolume contraction and reduced blood pressure levels. 相似文献
84.
85.
The ACTG076 trial showed that a complex and expensive antiretroviral regimen reduced mother-to-child HIV transmission by 67%. A more recent Bangkok perinatal HIV study found that oral zidovudine (AZT) given during late pregnancy and labor to non-breast-feeding women reduced the rate of vertical HIV transmission by 51%. These latter findings are particularly interesting to countries unable to afford the more expensive and complex 076 regimen. The reaction to the results of the Bangkok trial may, however, threaten the health of Africa's poorest women and children. Within days of the release of the Thai data, investigators studying other regimens closed recruitment to the placebo arms of their trials, and it has recently become clear that the National Institutes for Health will probably fund no more placebo-controlled trials of interventions designed to reduce maternal HIV transmission. The use of antiretroviral drugs in Africa is unlikely to ever significantly reduce maternal HIV transmission and the incidence of pediatric AIDS. While most of Africa's women have no option to breast-feed, breast-feeding is responsible for one-third of maternal HIV transmission cases. The results of the Thai trials only partially address the needs of African women, for the nutritional, immunological, and birth spacing benefits of breast-feeding should be retained if possible, and formula feeding may stigmatize HIV-infected mothers. The short-course regimen is still expensive to developing countries, and the implementation of a costly, vertical program may also draw financial and human resources from other programs. Placebo-controlled trials to develop simple, cheap, and effective potentially non-drug interventions against vertical HIV transmission should be encouraged in settings in which antiretroviral drugs and formula feeding cannot be safely delivered. 相似文献
86.
Tanja Lucas Karim Benihoud Frédéric Vigant Christoph Q. Andreas Schmidt Max G. Bachem Thomas Simmet Stefan Kochanek 《PloS one》2015,10(2)
Primary pancreatic carcinoma has an unfavourable prognosis and standard treatment strategies mostly fail in advanced cases. Virotherapy might overcome this resistance to current treatment modalities. However, data from clinical studies with oncolytic viruses, including replicating adenoviral (Ad) vectors, have shown only limited activity against pancreatic cancer and other carcinomas. Since pancreatic carcinomas have a complex tumor architecture and frequently a strong stromal compartment consisting of non-neoplastic cell types (mainly pancreatic stellate cells = hPSCs) and extracellular matrix, it is not surprising that Ad vectors replicating in neoplastic cells will likely fail to eradicate this aggressive tumor type. Because the TGFβ receptor (TGFBR) is expressed on both neoplastic cells and hPSCs we inserted the TGFBR targeting peptide CKS17 into the hypervariable region 5 (HVR5) of the capsid protein hexon with the aim to generate a replicating Ad vector with improved activity in complex tumors. We demonstrated increased transduction of both pancreatic cancer cell lines and of hPSCs and enhanced cytotoxicity in co-cultures of both cell types. Surface plasmon resonance analysis demonstrated decreased binding of coagulation factor X to CKS17-modified Ad particles and in vivo biodistribution studies performed in mice indicated decreased transduction of hepatocytes. Thus, to increase activity of replicating Ad vectors we propose to relax tumor cell selectivity by genetic hexon-mediated targeting to the TGFBR (or other receptors present on both neoplastic and non-neoplastic cells within the tumor) to enable replication also in the stromal cell compartment of tumors, while abolishing hepatocyte transduction, and thereby increasing safety. 相似文献
87.
88.
Croft DR Crighton D Samuel MS Lourenco FC Munro J Wood J Bensaad K Vousden KH Sansom OJ Ryan KM Olson MF 《Cell research》2011,21(4):666-682
The central arbiter of cell fate in response to DNA damage is p53, which regulates the expression of genes involved in cell cycle arrest, survival and apoptosis. Although many responses initiated by DNA damage have been characterized, the role of actin cytoskeleton regulators is largely unknown. We now show that RhoC and LIM kinase 2 (LIMK2) are direct p53 target genes induced by genotoxic agents. Although RhoC and LIMK2 have well-established roles in actin cytoskeleton regulation, our results indicate that activation of LIMK2 also has a pro-survival function following DNA damage. LIMK inhibition by siRNA-mediated knockdown or selective pharmacological blockade sensitized cells to radio- or chemotherapy, such that treatments that were sub-lethal when administered singly resulted in cell death when combined with LIMK inhibition. Our findings suggest that combining LIMK inhibitors with genotoxic therapies could be more efficacious than single-agent administration, and highlight a novel connection between actin cytoskeleton regulators and DNA damage-induced cell survival mechanisms. 相似文献
89.
Mohammad R. Karim Eric R. Rhodes Nichole Brinkman Larry Wymer G. Shay Fout 《Applied and environmental microbiology》2009,75(8):2393-2399
The U.S. Environmental Protection Agency''s information collection rule requires the use of 1MDS electropositive filters for concentrating enteric viruses from water, but unfortunately, these filters are not cost-effective for routine viral monitoring. In this study, an inexpensive electropositive cartridge filter, the NanoCeram filter, was evaluated for its ability to concentrate enteroviruses and noroviruses from large volumes of water. Seeded viruses were concentrated using the adsorption-elution procedure. The mean percent retention of seeded polioviruses by NanoCeram filters was 84%. To optimize the elution procedure, six protocols, each comprising two successive elutions with various lengths of filter immersion, were evaluated. The highest virus recovery (77%) was obtained by immersing the filters in beef extract for 1 minute during the first elution and for 15 min during the second elution. The recovery efficiencies of poliovirus, coxsackievirus B5, and echovirus 7 from 100-liter samples of seeded tap water were 54%, 27%, and 32%, respectively. There was no significant difference in virus recovery from tap water with a pH range of 6 to 9.5 and a water flow rate range of 5.5 liters/min to 20 liters/min. Finally, poliovirus and Norwalk virus recoveries by NanoCeram filters were compared to those by 1MDS filters, using tap water and Ohio River water. Poliovirus and Norwalk virus recoveries by NanoCeram filters from tap and river water were similar to or higher than those by the 1MDS filters. These data suggest that NanoCeram filters can be used as an inexpensive alternative to 1MDS filters for routine viral monitoring of water.Viruses that primarily infect and replicate in the gastrointestinal tract are known as enteric viruses. More than 140 different enteric viruses are known to infect humans. These include the enteroviruses, rotaviruses, hepatitis A virus, noroviruses, adenoviruses, and reoviruses, among others. Enteric viruses are capable of causing a wide range of illnesses, including gastroenteritis, paralysis, aseptic meningitis, herpangina, respiratory illness, fevers, myocarditis, etc. Given the potential public health impact of the enteric viruses, enteroviruses (echovirus and coxsackievirus), adenoviruses, and caliciviruses are on the U.S. Environmental Protection Agency''s contaminant candidate list 2 for regulatory consideration for drinking water (11). Within the Caliciviridae family, noroviruses are the primary viruses of concern for drinking water.Contaminated drinking water is considered to be a potential transmission route, and an infectious dose in humans may consist of only a small number of virus particles. Enteric viruses are introduced in aquatic environments through natural or human activities, such as leaking sewage and septic systems, urban runoff, landfills, injection of treated wastewater into aquifers, wastewater discharge, sewage outfall, etc. These viruses have been found in surface water, groundwater, and drinking water (1, 6, 13, 22, 26). Between 1971 and 2004, 789 drinking water outbreaks and 575,207 cases of illness were reported in the United States, and 8% of the reported outbreaks were due to enteric viruses (2, 5, 28, 29, 30, 46).The levels of enteric viruses in natural waters are often low, and as such, typical virus sampling involves a primary concentration of viruses from large volumes of water (hundreds to thousands of liters). Unlike other waterborne pathogens (such as bacteria and parasites), viruses are smaller, and thus, size exclusion filtration is often not practical, especially for turbid waters. In addition, viruses are negatively charged in natural environments and can be adsorbed onto a number of different matrices by electrostatic and hydrophobic interactions (16). Consequently, different types of matrices have been used to isolate enteric viruses from water. These include negatively and positively charged membranes or cartridge filters (10, 17, 32, 34, 35, 39), gauze pad (31), and glass powder or glass wool (14, 27). Of all of these methods, electronegative and electropositive filters are most commonly used. In the case of electronegative filters, the acidification of the water and addition of multivalent cations are required for optimal virus adsorption. Because of this need to condition the water to attain acceptable recoveries, it is difficult to use electronegative filters for field sampling. In contrast, electropositive filters do not require conditioning of the water. Among all the filters, 1MDS electropositive filters (Cuno, Meriden, CT) are the most commonly used filter for fresh and drinking water sampling; however, they are not cost-effective for routine viral monitoring of water and require pH adjustment for waters with pH values exceeding 8.0 (12).Viruses adsorbed on the filter are usually eluted and recovered using 1 to 1.6 liters of eluting solution (6, 12). Many different procedures are described in the literature to elute viruses from filters. These procedures include the use of different eluting solutions, such as 0.3%, 1.5% or 3% beef extract, urea-arginine phosphate buffer, glycine buffer, etc. (10, 12, 24, 37). There are also different elution processes, such as single elution, recirculation of eluents, or successive elution of filters (6, 8, 15, 43). Sobsey and Hickey (40) used only one elution with 0.3% beef extract in 50 mM glycine. Sobsey et al. (43) suggested that 1 liter of 1.5% beef extract be recirculated through the filters for 5 min. Dahling and Wright (8) reported that the highest virus recoveries were obtained by three elutions, each using 1.6 liters of 3% beef extract. Dahling (6) reported that the highest virus recoveries were obtained with two separate beef extract elutions, one being an overnight filter immersion in beef extract.Although methods for concentration of many enteric viruses have been developed, limited studies have been conducted for concentrating noroviruses from water. Huang et al. (21) described a norovirus concentration method using porcine calicivirus (Pan-1) as a surrogate. Pan-1 was sensitive to the high pH (9.5) of the eluting solution, which is commonly used. Myrmel et al. (33) described a method of norovirus concentration using feline calicivirus as a surrogate organism. The method used electronegative filters, and the recovery of virus was 5 to 10%. Many other studies reported detection of human noroviruses in environmental waters (18, 19, 25); however, none of these studies evaluated the recovery efficiencies of human noroviruses from large volumes of water.The objective of this study was to evaluate the NanoCeram (Argonide, Sanford, FL) cartridge filter for the concentration of enteroviruses and noroviruses from large volumes of water. NanoCeram filters have an active component of nano alumina (AlOOH) fibers, which give them a naturally occurring electropositive charge. 相似文献
90.