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关键词： Neopyropia yezoensis   Ulva prolifera   Growth   Competition   Elevated CO2   Photosynthetic performance  

摘要： The occurrence of various marine macroalgae in the same niche will inevitably lead to interspecific competition due to similar environmental requirements. With the increasing global atmospheric CO2 concentration, the resulting ocean acidification can potentially influence competition among macroalgae in the future. Neopyropia yezoensis (Rhodophyta, formerly Pyropia yezoensis) and the epiphytic alga Ulva prolifera (Chlorophyta) were selected for investigating competition among macroalgae grown under different CO2 conditions. The results showed that when cultured with U. prolifera, N. yezoensis' growth rate was significantly inhibited along with a sharp decrease in net photosynthetic rate. Although CO2 decreased the growth rate of N. yezoensis, it enhanced the resistance of the alga to the allelopathic effect of U. prolifera. While no difference was found between U. prolifera grown in monoculture and biculture, strong competitive ability was observed. CO2 could enhance this ability with higher net photosynthetic rate. However, CO2 significantly inhibited the carotenoid synthesis in both plants. This inhibition in N. yezoensis was more pronounced in the presence of U. prolifera. Biculture promoted the accumulation of soluble protein in N. yezoensis while it inhibited the process in U. prolifera. In addition, it enhanced the inhibitory effect of acidification on soluble carbohydrates of both plants. Elevated CO2 levels alleviated the competition between N. yezoensis and U. prolifera, but the latter can become the more competitive epiphytic alga which can impact the future of nori culture.

关键词： Methyl mercury chloride   Oreochromis niloticus   Metallothionein   GPX   GSR   Gene expression  

摘要： Methyl mercury chloride "MMC" (CH3ClHg) is an ubiquitous environmental toxicant that causes a variety of adverse effects. In the present study, we investigated the effects of sub-chronic toxicity of MMC on Nile tilapia (Oreochromis niloticus) through the evaluation of growth performance and hematological, biochemical, and oxidative stress biomarkers. From 150 healthy fish, five equally sized treatment groups were created: a control (CT) group fed with a basal diet and four MMC treatment groups exposed to 0.5, 1, 1.5, and 2 mg of MMC per kg of basal diet for 60 days. MMC exposure significantly reduced the growth performance and survival of O. niloticus and decreased red blood cell count and hemoglobin concentration. Treated fish exhibited normocytic normochromic anemia in addition to leucopenia, lymphopenia, granulocytopenia, and monocytopenia. Moreover, MMC exposure significantly affected liver function, including a reduction in the total protein levels while increasing cholesterol and triglyceride levels. It also markedly increased the production of stress biomarkers such as glucose and cortisol levels. Furthermore, MMC significantly elevated the levels of hepatic enzymes, induced tissue damage, and caused inflammation, as indicated by the upregulation of mRNA expression of hepatic metallothionein. Finally, MMC exposure induced oxidative stress by altering the antioxidant status of the liver and downregulating the mRNA expression of superoxide dismutase, glutathione peroxidase, and glutathione S-reductase. In conclusion, MMC toxicity induced hematological and biochemical alterations, leading to an enhanced state of oxidative stress in O. niloticus.

关键词： Heat shock proteins   Heat tolerance   Molecular markers   Organic osmolytes   Physiological processes  

摘要： Improvement in tolerance to stresses, including heat stress, through classical breeding or a biotechnological approach depends on precise selection criteria. The criteria could be morphological characteristics, yield attributes, or physio-biochemical and molecular processes. Classical plant breeders have conducted breeding programs to achieve enhanced stress tolerance or yield often without acquiring a knowledge of the pertinent physiological processes mediating such traits. However, breeding based on yield per se has not been so successful because yield is not a significantly heritable trait. Thus, for a successful breeding program, knowledge of physiobiochemical and molecular processes involved in stress tolerance is indispensable. In this review, various viable physio-biochemical and molecular selection criteria are discussed that could be used by breeders or biotechnologists to improve thermotolerance in important crops. How far these criteria are consistently expressed at different plant phenological stages and how their expression varies between species or between cultivars are also deliberated in the review. This will enable biotechnologists to direct their programs precisely to identify the specific genes and carry out gene editing using advanced viable techniques to achieve enhanced thermotolerance in plants.

关键词： Filarial nematodes   Acanthocheilonema spp   CVBDs   Hunting dogs  

摘要： Acanthocheilonema reconditum is a filarial parasite transmitted by arthropods (fleas, lice, and ticks) that infect dogs. There is minimal published data available to date on potential haematological and biochemical changes associated with this parasitic infection. Study aims were (i) provide an overview of A. reconditum in Europe, (ii) define A. reconditum prevalence and risk factors in a specific dog population (hunting) from southern Italy, and (iii) assess the frequency of haemato-biochemical abnormalities associated with infection. Blood samples collected from 3020 dogs were tested by a modified Knott's technique to count and identify microfilariae. Eighty-four dogs were infected by A. reconditum (2.78%;95% CI 2.19-3.37%). Microfilariae ranged from 1 to 212/ml. Based on clinical examination, all but six dogs with non-specific symptoms were healthy. Haematological abnormalities included leucocytosis (n = 15), with eosinophilia (n = 14) and monocytosis (n = 13). Serum biochemical abnormalities included increased total serum proteins (n = 19), albumins (n = 7), total globulins (n = 14), ALT (n = 1), and ALP (n = 1);one dog was hypoalbuminemic, and BUN was mildly increased in 2 dogs. Risk factors included the province origin (Napoli, OR=5.4, 95%CI: 2.1-14.0;Caserta, OR=5.1, 95%CI: 2.5-10.6), hunting wild mammals (OR=2.8, 95% 95%CI: 1.6-4.8), and ectoparasite infestation (OR=1.9, 95%CI: 1.1-3.1). There was a negative correlation between microfilaraemic load and decreased albumin level (-0.37;p=0.021). Our results showed that A. reconditum circulates within the hunting dog population of southern Italy, with seemingly low pathogenic potential.

关键词： Bay Islands   Ethno-botany   Fatty acid composition   Myristicaceae   Total phenolic content  

摘要： Key message Wild nutmeg species could be utilized as a source of fatty acids like the cultivated nutmeg. Myristicaceae is a tropical family, the members of which are utilized for medicinal properties in their native regions. Myristica fragrans is a species commercially exploited as a spice and medicine worldwide, while most of its allied species are yet to be studied in detail. In present study, three species viz. Horsfieldia glabra, Knema andamanica and Myristica andamanica were compared with the commercial nutmeg morphologically and biochemically to identify their utilization potential. Distinct variations were observed for seed morphological parameters among these species and seed dimensions were found to be the maximum in seeds of M. andamanica. Extraction yield varied significantly with solvent in H. glabra, K. andamanica and M. fragrans. Higher total phenolic content was recorded in methanolic extracts than acetone extracts in all the species and methanolic extract of M. andamanica had the highest total phenolic content (6.54 mg/g GAE). Seeds of all species were rich in saturated fats that varied between 59.4% (H. glabra) and 83.4% (M. andamanica). Methyl tetradecanoate was the most dominant compound in all the species, the content of which varied between 46.87 and 68.84%, while (Z)-9-octadecenoic acid methyl ester and methyl hexadecanoate were the other dominant compounds. Higher quantities of methyl dodecanoate (27.02%) and methyl cis -13-docosenoate (16.97%) were obtained from M. andamanica and H. glabra, respectively, while these compounds were present in minute quantities in other species.

关键词： N-terminally-truncated Aβ   PE3-42Aβ   Aminopeptidase A   Inhibitors   ShRNA   Senile plaques   Dendritic spines   Behavior   Transgenic mice   Alzheimer Disease  

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  

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  

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  

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.