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关键词： N-terminally-truncated AβPE3-42AβAminopeptidase A   Inhibitors   ShRNA   Senile plaques   Dendritic spines   Behavior   Transgenic mice   Alzheimer Disease   AMYLOID PRECURSOR PROTEIN   RENIN-ANGIOTENSIN SYSTEM   APATHY-LIKE BEHAVIOR   GLUTAMINYL CYCLASE   BETA-PROTEIN   SYNAPTIC PLASTICITY   WORKING-MEMORY   3XTG-AD MOUSE   DEFICITS   PLAQUES  

摘要： One of the main components of senile plaques in Alzheimer's disease (AD)-affected brain is the A beta peptide species harboring a pyroglutamate at position three pE3-A beta. Several studies indicated that pE3-A beta is toxic, prone to aggregation and serves as a seed of A beta aggregation. The cyclisation of the glutamate residue is produced by glutaminyl cyclase, the pharmacological and genetic reductions of which significantly alleviate AD-related anatomical lesions and cognitive defects in mice models. The cyclisation of the glutamate in position 3 requires prior removal of the A beta N-terminal aspartyl residue to allow subsequent biotransformation. The enzyme responsible for this rate-limiting catalytic step and its relevance as a putative trigger of AD pathology remained yet to be established. Here, we identify aminopeptidase A as the main exopeptidase involved in the N-terminal truncation of A beta and document its key contribution to AD-related anatomical and behavioral defects. First, we show by mass spectrometry that human recombinant aminopeptidase A (APA) truncates synthetic A beta 1-40 to yield A beta 2-40. We demonstrate that the pharmacological blockade of APA with its selective inhibitor RB150 restores the density of mature spines and significantly reduced filopodia-like processes in hippocampal organotypic slices cultures virally transduced with the Swedish mutated A beta-precursor protein (beta APP). Pharmacological reduction of APA activity and lowering of its expression by shRNA affect pE3-42A beta- and A beta 1-42-positive plaques and expressions in 3xTg-AD mice brains. Further, we show that both APA inhibitors and shRNA partly alleviate learning and memory deficits observed in 3xTg-AD mice. Importantly, we demonstrate that, concomitantly to the occurrence of pE3-42A beta-positive plaques, APA activity is augmented at early Braak stages in sporadic AD brains. Overall, our data indicate that APA is a key enzyme involved in A beta N-terminal trunc

关键词： Three spotted crab   Icing   Refrigeration   Biogenic amine   Food safety   VOLATILE AMINES   QUALITY   FISH   MUSCLE   LIFE   RED  

摘要： Three spotted crab (Portunus sanguinolentus) is a preferred variety of crab among seafood consumers. Biochemical, microbial and sensory characters along with formation of biogenic amines of whole crabs stored under iced and refrigerated condition was evaluated. Cadaverine, putrescine and spermidine were the major amines formed during spoilage and a strong correlation between cadaverine and psychrotrophs was observed in refrigerated (0.92) and iced storage (0.86) respectively. Histamine was at lower level and not likely to cause any toxicological problems to consumers. Although TVB-N and TMA-N increased significantly (p < 0.01), TVBN was observed as a good indicator of spoilage than TMA-N. Mesophilic and psychrotrophic bacteria crossed 7 log CFU/g on 8th day, rejection day of refrigeration, while it was below spoilage limit in iced storage. A shelf life of 6 and 10 days were observed in storage under refrigeration and icing respectively based on microbiological, biochemical and sensory attributes.

关键词： Historical medicines   Artifact analysis   Mass spectrometry   Tucson   Arizona   CHEMICAL-ANALYSIS  

摘要： In the last decade, historical archaeologists in the American West have begun conducting biochemical analyses of contents in bottles recovered from archaeological sites dating to the late nineteenth and early twentieth centuries. Archaeological excavations conducted at the Alameda-Stone Cemetery Site provided a large amount of data about the residents of a Tucson, Arizona neighborhood that existed between 1889 and the 1950s. This was a transformative period in the pharmaceutical industry when university-trained pharmacists advanced their field and advocated against the use of mass-produced patent and proprietary medicines. The discovery of two sealed medicine bottles with intact contents provided an opportunity to examine medicinal products from bygone days. This analysis centered on the main question: What can archaeologists discover about the contents of historical bottles that were discarded and have been subjected to environmental conditions for decades? The bottle contents from Tucson were analyzed by gas chromatograph/mass spectrometry (GC/MS) to reveal the ingredients of the medicines and were compared with biochemical medicine analysis conducted at other sites in the American West. These results, in conjunction with historical and archaeological data, demonstrate archaeologically recovered medicines can provide insight into pharmacy and medicine ingredients used in the American West during the late nineteenth and early twentieth centuries.

关键词： Threonine dehydratase   l-Threonine   d-Amino acid   Amino acid racemase   Thermotoga maritima   D-AMINO ACIDS   INHIBIT BIOFILM FORMATION   ESCHERICHIA-COLI   LYSINE RACEMASE   VANCOMYCIN RESISTANCE   ALLOSTERIC REGULATION   ASPARTATE RACEMASE   BACILLUS-SUBTILIS   STRUCTURAL BASIS   CELL-WALL  

摘要： The peptidoglycan of the hyperthermophile Thermotoga maritima contains an unusual component, d-lysine (d-Lys), in addition to the typical d-alanine (d-Ala) and d-glutamate (d-Glu). In a previous study, we identified a Lys racemase that is presumably associated with d-Lys biosynthesis. However, our understanding of d-amino acid metabolism in T. maritima and other bacteria remains limited, although d-amino acids in the peptidoglycan are crucial for preserving bacterial cell structure and resistance to environmental threats. Herein, we characterized enzymatic and structural properties of TM0356 that shares a high amino acid sequence identity with serine (Ser) racemase. The results revealed that TM0356 forms a tetramer with each subunit containing a pyridoxal 5 '-phosphate as a cofactor. The enzyme did not exhibit racemase activity toward various amino acids including Ser, and dehydratase activity was highest toward l-threonine (l-Thr). It also acted on l-Ser and l-allo-Thr, but not on the corresponding d-amino acids. The catalytic mechanism did not follow typical Michaelis-Menten kinetics; it displayed a sigmoidal dependence on substrate concentration, with highest catalytic efficiency (k(cat)/K-0.5) toward l-Thr. Interestingly, dehydratase activity was insensitive to allosteric regulators l-valine and l-isoleucine (l-Ile) at low concentrations, while these l-amino acids are inhibitors at high concentrations. Thus, TM0356 is a biosynthetic Thr dehydratase responsible for the conversion of l-Thr to alpha-ketobutyrate and ammonia, which is presumably involved in the first step of the biosynthesis of l-Ile.

关键词： Arbuscular mycorrhizal fungi   Compost   Soil fertility   Yield   Allium sativum   ARBUSCULAR MYCORRHIZAL FUNGI   MICROBIAL COMMUNITY   PLANT-GROWTH   WATER-STRESS   AM FUNGI   INOCULATION   L.   FERTILIZATION   AMENDMENT   FIELD  

摘要： The present work aimed to study the effect of compost and arbuscular mycorrhizal fungi (AMF) on soil physicochemical parameters on garlic (Allium sativum L.) growth, physiology, biochemical traits, and yield under environmental conditions. The application of AMF or compost increased both carbonic and mineral contents in soil. An improvement of 92% and 35% was observed in case of total organic carbon in soil of plant amended with compost and inoculated with AMF, respectively, compared to the control. Indeed, available phosphorus and total nitrogen were increased by 139% and 52% in case of compost + AMF compared to the control. Mycorrhizal frequency was significantly higher in AMF than in compost + AMF plants, while compost application did not significantly affect the mycorrhizal intensity in garlic roots. The application of R. irregularis, compost, and their combination enhanced the growth parameters and biomass production with the greatest improvement in AMF and compost + AMF treatments. Compost + AMF was considered the best treatment, with a yield improvement by 81% in comparison to the control. The same biostimulants applied alone or in combination significantly enhanced stomatal conductance, total soluble sugars, proteins, and the content of chlorophyll and total carotenoid in garlic plants compared to the control. Finally, we revealed the positive impact of the tested biofertilizers and the interest in adoption of innovative practices improving growth, physiology, biochemical traits, and soil fertility as well as biological agriculture of garlic yield.

关键词： Climate changes   Drought   Oxidative stress   Sandy soil   Sunflower yield   STRESS TOLERANCE   PHYSIOLOGICAL TRAITS   PROLINE ACCUMULATION   NUTRIENT-UPTAKE   WATER-USE   OXYGEN   METABOLISM   DROUGHT   PLANTS   TEMPERATURE  

摘要： Maximizing the utilization of water unit is of paramount importance in arid zones and worldwide. This is even more significant when plants are subjected to both thermal and water stress. Hence, a two-year (2014 and 2015 seasons) field trial was carried out to study the effect of three sowing dates (April 21, May 21, and June 21); two irrigation levels (I100 and I85) and two ascorbic acid rates, ASA (0 and 450 mg L-1), on physiological and biochemical traits, productivity and water use efficiency (WUE) of sunflower. Results showed that subjecting sunflower plants to water deficit under any sowing date caused decreases in chlorophyll, carotenoids, oil% and seed yield and an increase in proline content. As averages of the two seasons, ASA treated plants caused increases in seed yield amounted to 11.7%, 10.6% and 8.4% with I100 and 5.1%, 14.4% and 7.7% with I85 compared to non-treated plants sown in April, May and June, respectively. In ASA treated plots, WUE values of sowing in April x I100 or sowing in June x I85 in 2014 and sowing in May x I85 in 2015 were as similar as that of conventional practice (sowing in May x I100 x 0 mg L-1 ASA). Accordingly, results clarify that ASA can be used successfully in sunflower management programs, particularly under abiotic stresses e.g. unfavorable heat and drought.

关键词： Mixed blue and red-orange light   Light inhibition   Growth kinetics   Biochemical profile   Chlorophyceae   LIGHT-EMITTING-DIODES   LIPID-ACCUMULATION   MICROALGAL BIOMASS   BIOGAS UPGRADE   QUALITY   OPTIMIZATION   WAVELENGTHS   PROTEIN   ALGAE   PHOTOBIOREACTOR  

摘要： Light management methods are considered effective to enhance the quantum yield and photosynthetic efficiency and promote the biomass and nutrient production; however, light saturation and inhibition restrain further improvement. This work studies the effect of light mixing on algal light saturation/inhibition, growth kinetics, and biochemical profile. The green alga Chlamydomonas reinhardtii was cultivated with batch culture under an LED light panel with multiple spectra options. Different combinations of blue (B) and red-orange (RO) light intensities were tested with blue light ranging from 45 to 65 mu mol photons m(-2) s(-1) and red-orange light ranging from 45 to 205 mu mol photons m(-2) s(-1). Results reveal that the mixed blue and red-orange light significantly improved the growth kinetics and relieved the light saturation under blue light and the light inhibition under the red-orange light. The maximum specific growth rate, biomass concentration, and productivity increased by 22, 50, and 57%, respectively, compared with the results under the red-orange light. The lipid and protein synthesis were observed to be promoted under mixed light with relatively low red-orange light intensities (45 and 105 mu mol photons m(-2) s(-1)) and repressed at high red-orange light intensities (155 and 205 mu mol photons m(-2) s(-1)). The carbohydrate content did not change.

关键词： Paenibacillus polymyxa   Performance   Blood biochemistry   Intestinal microbiota   Quail   LACTIC-ACID BACTERIA   BACILLUS-SUBTILIS   CARCASS CHARACTERISTICS   IMMUNE-RESPONSE   ANTIBACTERIAL ACTIVITY   PERFORMANCE   SUPPLEMENTATION   PROBIOTICS   PARAMETERS   METABOLITES  

摘要： This study investigated the effect of Paenibacillus polymyxa LM31 supplementation on growth performance, antioxidative status, immune response, cecal microbiota, and biochemical parameters of growing Japanese quail. Identification of Paenibacillus polymyxa was identified and the volatile organic compounds and antibacterial activity of selected isolate supernatant were determined. A total of 225 unsexed one-wk-old Japanese quail chicks were randomly allocated to 5 treatments (5 pens, 9 birds/pen) and fed either a basal diet as a control group or a basal diet supplemented with four different levels of Paenibacillus polymyxa 0.1, 0.2, 0.3 and 0.4 mg / kg feed. The results of the GC mass profile revealed that several organic compounds were secreted by Paenibacillus polymyxa in the supernatant. The diet supplemented with Paenibacillus polymyxa supernatant showed potent antibacterial properties against gram negative and gram positive bacteria as well as fungi. Paenibacillus polymyxa significantly improved the growth performance of growing quails. Paenibacillus polymyxa administration up to 0.4 mg/kg diet significantly reduced plasma total cholesterol (TC), low density lipoprotein (LDL), very low density lipoprotein (VLDL), and triglycerides (TG). The use of Paenibacillus polymyxa at 0.3 or 0.4 mg/kg diet significantly (P = 0.0042) increased high density lipoprotein (HDL) compared to the control. In addition, dietary supplementation of 0.3 mg Paenibacillus polymyxa /kg diet significantly improved superoxide dismutase (SOD), total antioxidant capacity (TAC), immunoglobulin M (IgM) and Immunoglobulin G (IgG) whereas significantly reduced plasma lipid peroxidation (MDA). Furthermore, Paenibacillus polymyxa administration modulated ceacal microbiota by significantly reducing the count of E. coli and Enterococcus spp. whereas increased lactic acid bacteria. In conclusion, Paenibacillus polymyxa could improve productive performance and body health status of Japanese

关键词： Blood pressure   Cardiovascular function   Polycystic ovary syndrome (PCOS)   Sex hormones   Hyperandrogenism   N-terminal of the prohormone of B-type natriuretic peptide (NT-proBNP)   BRAIN NATRIURETIC PEPTIDE   BODY-MASS INDEX   BLOOD-PRESSURE   INSULIN-RESISTANCE   NT-PROBNP   CIRCULATING LEVELS   GENE-EXPRESSION   ADIPOSE-TISSUE   HEART-FAILURE   OBESITY  

摘要： Purpose Women with polycystic ovary syndrome (PCOS) present with or without biochemical hyperandrogenism (HAPCOS or non-HAPCOS, respectively). Cardiometabolic and hormonal abnormalities have been reported in women with PCOS, particularly those with hypertension. However, no direct comparison between normotensive (blood pressure <140/90 mmHg) patients with HAPCOS and non-HAPCOS has been made. This study compared different cardiovascular (CV), anthropometric, metabolic and hormonal features between normotensive patients with HAPCOS and non-HAPCOS and healthy women. Methods We consecutively recruited 249 normotensive patients with PCOS and 85 healthy eumenorrheic women to a case-control observational study. Based on blood androgen concentration, patients with PCOS were divided into HAPCOS (n = 69) or non-HAPCOS (n = 180) groups. Results Although within normal ranges, patients with HAPCOS had significantly (p < 0.05) higher peripheral and central systolic blood pressure and pulse pressure, C-reactive protein, low-density lipoprotein cholesterol, triglycerides, glucose, and insulin than subjects with non-HAPCOS, and healthy women. They also had lower N-terminal prohormone of B-type natriuretic peptide (NT-proBNP) concentration. In contrast, their body mass index (BMI) was higher of over 4 kg/m(2) than patients with non-HAPCOS and nearly 6 kg/m(2) than in healthy participants. Except for BMI, statistical differences in the cardiometabolic profile were of little clinical relevance. Conclusions Young normotensive women with HAPCOS have a worse cardiometabolic profile but lower NT-proBNP concentration than patients with non-HAPCOS. Features of this profile in both PCOS groups are within ranges typical for healthy women. Increased BMI is the only clinically relevant feature differentiating hyperandrogenic from non-hyperandrogenic patients with PCOS, and healthy women.

关键词： Induced resistance   Passiflora edulis   IPM   Phenolics   Enzyme activity   FUNCTIONAL-CHARACTERIZATION   RESISTANCE   INDUCTION   PLANTS   TRANSPORTERS   HEMIPTERA   HORMESIS   DEFENSE   GROWTH  

摘要： Silicon (Si) is agronomically beneficial due to positive effects it provides to plant development, including the increased defensive response capacity against attack of herbivorous insects. This study evaluated the effects of applications of Si sources via soil and foliar sprays on yellow passion fruit biochemistry and Si-induced resistance to feeding preference and development of the major passion fruit pest, Dione juno juno. Two independent experiments were conducted with applications of calcium silicate (78-88% SiO2) via soil and as foliar sprays with the commercial product AgriSil (R) (98% SiO2) to plants of Passiflora edulis f. flavicarpa in a greenhouse. Four doses were tested for each Si source plus a control treatment. Biochemical analyses in the plants included the concentrations of Si and total phenolics, and activities of the enzymes peroxidase (POX), phenylalanine ammonia lyase (PAL), and polyphenol oxidase (PPO). Si-induced resistance to D. juno juno was investigated in feeding assays in the laboratory and on the insect's development on potted-plants in the greenhouse. As main results, calcium silicate favoured the increase in Si content and the activities of POX and PAL, in addition to negatively affecting larvae feeding preference, leaf area consumed, and adult-stage parameters of D. juno juno. Agrisil led to increased Si content, total phenolics concentration, and POX activity, but did not affect the feeding preference, performance, and development of D. juno juno. Calcium silicate is promising for use in integrated pest management and could provide benefits to passion fruit production by reducing the economic losses by D. juno juno attack.