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81.
Rungapamestry V Duncan AJ Fuller Z Ratcliffe B 《Journal of agricultural and food chemistry》2006,54(20):7628-7634
In cabbage, glucosinolates such as sinigrin are hydrolyzed by plant myrosinase to allyl isothiocyanate (AITC), allyl cyanide, and, in the presence of an epithiospecifier protein, 1-cyano-2,3-epithiopropane (CEP). Isothiocyanates have been implicated in the cancer-protective effects of Brassica vegetables. The effect of processing on the hydrolysis of glucosinolates was investigated in cabbage. Cabbage was steamed or microwaved for six time durations over 7 min. Glucosinolate concentrations were slightly reduced after microwave cooking (P < 0.001) but were not influenced after steaming (P < 0.05). Myrosinase activity was effectively lost after 2 min of microwave cooking and after 7 min of steaming. Hydrolysis of residual glucosinolates following cooking yielded predominantly CEP at short cooking durations and AITC at longer durations until myrosinase activity was lost. Lightly cooked cabbage produced the highest yield of AITC on hydrolysis in vitro, suggesting that cooking Brassica vegetables for a relatively short duration may be desirable from a health perspective. 相似文献
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Njabo KY Fuller TL Chasar A Pollinger JP Cattoli G Terregino C Monne I Reynes JM Njouom R Smith TB 《Veterinary microbiology》2012,156(1-2):189-192
Although swine origin A/H1N1/2009 influenza virus (hereafter "pH1N1″) has been detected in swine in 20 countries, there has been no published surveillance of the virus in African livestock. The objective of this study was to assess the circulation of influenza A viruses, including pH1N1 in swine in Cameroon, Central Africa. We collected 108 nasal swabs and 98 sera samples from domestic pigs randomly sampled at 11 herds in villages and farms in Cameroon. pH1N1 was isolated from two swine sampled in northern Cameroon in January 2010. Sera from 28% of these herds were positive for influenza A by competitive ELISA and 92.6% of these swine showed cross reactivity with pandemic A/H1N1/2009 influenza virus isolated from humans. These results provide the first evidence of this virus in the animal population in Africa. In light of the significant role of swine in the ecology of influenza viruses, our results call for greater monitoring and study in Central Africa. 相似文献
85.
Abstract Various stressors affect the health of wild and cultured fish and can cause metabolic disturbances that first manifest at the cellular level. Here, we sought to further our understanding of cellular metabolism in fish by examining the metabolic responses of cell lines derived from channel catfish Ictalurus puntatus (CCO), white bass Morone chrysops (WBE), and fathead minnow Pimephales promelas (EPC) to both mitochondrial and thermal stressors. Using extracellular flux (EF) technology, we simultaneously measured the oxygen consumption rate (OCR; a measure of mitochondrial function) and extracellular acidification rate (ECAR; a surrogate of glycolysis) in each cell type. We performed a mitochondrial function protocol whereby compounds modulating different components of mitochondrial respiration were sequentially exposed to cells. This provided us with basal and maximal OCR, OCR linked to ATP production, OCR from ion movement across the mitochondrial inner membrane, the reserve capacity, and OCR independent of the electron transport chain. After heat shock, EPC and CCO significantly decreased OCR and all three cell lines modestly increased ECAR. After heat shock, the reserve capacity, the mitochondrial energetic reserve used to cope with stress and increased bioenergetic demand, was unaffected in EPC and CCO and completely abrogated in WBE. These findings provide proof-of-concept experimental data that further highlight the utility of fish cell lines as tools for modeling bioenergetics. Received April 12, 2012; accepted August 5, 2012 相似文献
86.
Maternal recognition of pregnancy refers to the requirement for the conceptus(embryo and its associated extraembryonic membranes) to produce a hormone that acts on the uterus and/or corpus luteum(CL) to ensure maintenance of a functional CL for production of progesterone;the hormone required for pregnancy in most mammals.The pregnancy recognition signal in primates is chorionic gonadotrophin which acts directly on the CL via luteinizing hormone receptors to ensure maintenance of functional CL during pregnancy.In ruminants,interferon tau(IFNT) is the pregnancy recognition signal.IFNT is secreted during the peri-implantation period of pregnancy and acts on uterine epithelia to silence expression of estrogen receptor alpha and oxytocin receptor which abrogates the oxytocin-dependent release of luteolytic pulses of prostaglandin F2-alpha(PGF) by uterine epithelia;therefore,the CL continues to produce progesterone required for pregnancy.Pig conceptuses secrete interferon delta and interferon gamma during the peri-implantation period of pregnancy,but there is no evidence that they are involved in pregnancy recognition signaling.Rather,pig conceptuses secrete abundant amounts of estrogens between Days 11 to 15 of pregnancy required for maternal recognition of pregnancy.Estrogen,likely in concert with prolactin,prevents secretion of PGF into the uterine venous drainage(endocrine secretion),but maintains secretion of PGF into the uterine lumen(exocrine secretion) where it is metabolized to a form that is not luteolytic.Since PGF is sequestered within the uterine lumen and unavailable to induce luteolysis,functional CL are maintained for production of progesterone.In addition to effects of chorionic gonadotrophin,IFNT and estrogens to signal pregnancy recognition,these hormones act on uterine epithelia to enhance expression of genes critical for growth and development of the conceptus. 相似文献
87.
Effect of Chemical or Electrical Activation of Bovine Oocytes on Blastocyst Development and Quality 总被引:2,自引:0,他引:2
MP Milazzotto WB Feitosa ARS Coutinho MD Goissis VP Oliveira MEOA Assumpção JA Visintin 《Reproduction in domestic animals》2008,43(3):319-322
Activation of in vitro‐matured (IVM) oocytes is essential for successful embryo production following nuclear transfer (NT) or intracytoplasmic sperm injection (ICSI). This study was designed to compare the rates of blastocyst production and embryo quality (as measured by numbers of viable cells) following parthenogenetic activation with electrical pulse or the use of two different calcium ionophores, A23187 (CA) or ionomycin (IO), with or without the addition of bovine serum albumin (BSA). IVM oocytes with a first polar body were randomly allocated to five treatment groups: CA (5 μm CA, 5 min; n = 88), CA + BSA (5 μm CA, 5 min; BSA, 5 min; n = 90), IO (5 μm IO, 5 min; n = 91), IO + BSA (5 μm IO, 5 min; BSA, 5 min; n = 86) and EL (two pulses of 1.5 kV/cm, 20 μs; n = 120). Blastocyst rates were higher (p < 0.05) for CA (54.4%), IO (51.4%) and EL (54.5%) than for IO + BSA (18.3%). Treatment CA + BSA (39.8%) did not differ from the others. There was no difference (p > 0.05) among treatments in total number of cells. However, the percentage of viable cells was reduced in CA (49.9%), CA + BSA (45.8%), IO (64.9%), IO + BSA (50.9%) compared with EL (82.7%). In summary, the addition of BSA to the IO treatment had an adverse effect on blastocyst production rates. Although there was no difference between electrical stimulation and chemical activation on blastocyst production rates, electrical activation resulted in blastocysts with a higher percentage of viable cells. 相似文献
88.
Martina Mosing Dr med vet DECVAA Isabelle K. Iff Dr med vet DECVAA Wolfgang Nemetz MD 《Journal of Veterinary Emergency and Critical Care》2008,18(5):532-536
Objective – To describe general anesthesia and successful resuscitation of a dog developing asystole and apnea during extradural injection of local anesthetic and an opioid. Case Summary – A Beagle with a ruptured cranial cruciate was premedicated with acepromazine and methadone. Anesthesia was induced with propofol and, after endotracheal intubation, maintained using isoflurane in oxygen. During extradural injection of a mixture of lidocaine, bupivacaine, and morphine the dog developed apnea and asystole. Cardiopulmonary cerebral resuscitation was started promptly and the dog was successfully resuscitated. New Information Provided – Asystole and apnea are possible serious side effects of extradural anesthesia in dogs. With adequate monitoring and early detection successful resuscitation is possible. 相似文献
89.
Effects of esmolol on systemic hemodynamics and heart rate variability measured using the Analgesia/Nociception Index in resuscitated piglets with Pseudomonas aeruginosa septic shock 下载免费PDF全文
Emmanuel Boselli MD PhD Matthias Jacquet‐Lagrèze MD Jean‐Yves Ayoub DVM Lionel Bouvet MD PhD Olivier Dauwalder PharmD PhD Christelle Mansour DVM Thomas Margez Eng Christian Paquet Eng Damien Restagno MSc Bernard Allaouchiche MD PhD Jeanne‐Marie Bonnet‐Garin DVM PhD Stéphane Junot DVM PhD 《Journal of Veterinary Emergency and Critical Care》2018,28(5):447-456
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