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关键词： Aquaculture   Biochemical composition   Macroalgae   Relative growth rate   Ulva fenestrata   Ulva lactuca   Chlorophyceae  

摘要： Ulva fenestrata is an economically and ecologically important green algal species with a large potential in seaweed aquaculture due to its high productivity, wide environmental tolerance, as well as interesting functional and nutritional properties. Here, we performed a series of manipulative cultivation experiments in order to investigate the effects of irradiance (50, 100, and 160 mu mol photons m(-2) s(-1)), temperature (13 and 18 degrees C), nitrate (< 5, 150, and 500 mu M), phosphate (< 1 and 50 mu M), and pCO(2) (200, 400, and 2500 ppm) on the relative growth rate and biochemical composition (fatty acid, protein, phenolic, ash, and biochar content) in indoor tank cultivation of Swedish U. fenestrata. High irradiance and low temperature were optimal for the growth of this northern hemisphere U. fenestrata strain, but addition of nutrients or changes in pCO(2) levels were not necessary to increase growth. Low irradiance resulted in the highest fatty acid, protein, and phenolic content, while low temperature had a negative effect on the fatty acid content but a positive effect on the protein content. Addition of nutrients (especially nitrate) increased the fatty acid, protein, and phenolic content. High nitrate levels decreased the total ash content of the seaweeds. The char content of the seaweeds did not change in response to any of the manipulated factors, and the only significant effect of changes in pCO(2) was a negative relationship with phenolic content. We conclude that the optimal cultivation conditions for Swedish U. fenestrata are dependent on the desired biomass traits (biomass yield or biochemical composition).

关键词： chemokine   cytokine   growth factor   premature ovarian insufficiency  

摘要： Problem Premature ovarian insufficiency (POI) imposes great challenge on female reproduction. Whether immune disturbance in ovarian environment was implicated in POI remains unclear. We aimed to characterize the cytokine profile in follicular fluid (FF) and paired serum in patients with biochemical POI (bPOI). Method of study Multiplex immunoassay containing 45 cytokines was performed for individual FF and paired serum samples from 35 bPOI patients and 37 matched controls. Cytokine profiles were compared between the two groups and cytokines correlated to ovarian reserve, and the rates of day-3 good-quality embryos were further analyzed. Results In FF, significantly elevated level of chemokines MIP-1 alpha (P = .043), CXCL8 (P = .024), IP-10 (P = .041), and eotaxin-1 (P = .015) as well as growth factors VEGF-D (P = .047), BDNF (P = .043), LIF (P = .002), and bFGF (P = .046) was found in bPOI patients compared to controls. Yet RANTES manifested an opposite trend with reduced levels among bPOI patients (P = .006). All these chemokines and growth factors in FF were significantly correlated with ovarian reserve (P < .05). In paired serum, cytokine signature was not likely accordant with that in FF between two groups, except for increased IP-10 (P = .032) in bPOI patients and its significant correlation to FSH and AFC (P < .05). Among all differentially expressed cytokines, RANTES in FF was correlated with the rate of day-3 good-quality embryos (P = .035). Conclusion Altered cytokine profile characterized by increased chemokines and growth factors was associated with early stage of POI, which may fuel the progression of the disease or even play a crucial role in the development of ovarian insufficiency.

关键词： Rett syndrome   Cytogenetic abnormalities   Biochemical   Serotonin   MeCP2   XCI  

摘要： Rett syndrome (RTT) is a stern dominant progressive neurological development disorder linked with X chromosome ranking second for mental slowdown, exclusively in females after few months of birth with normal development and growth period. Genetically any defects in universally expressed methyl-CpG binding protein 2 (MeCP2) transcription regulator gene are considered as radix for RTT in almost all the previous studies. Our study mainly focuses in unraveling the genetic alterations like identifying MeCP2 gene polymorphisms, chromosomal abnormalities, or X-chromosome inactivation (XCI) as underlying cause of RTT in prototypes sorted through Diagnostic and Statistical Manual of Mental Disorders-Text Revised (DSM IV). In addition, we have examined the probable surrogates of brain function disabilities like serotonin, homocysteine (Hcy), calcium, potassium, and lead from blood in both RTT porotypes and their mothers. In our investigation, we have observed varied amino acid substitution of MeCP2 and varied frequency of skewed XCI in RTT prototype. Our study validates that the demonstration of chromosomal analysis, biochemical analysis, and genomic observations helps in concluding BIT condition and can be helpful in providing appropriate treatment and counseling as well as improve the currently available protocol of diagnosis. (C) 2020 Elsevier Inc. All rights reserved.

关键词： acne scars   AirGent   EnerJet   hyaluronic acid   hypertrophic scars   liquid jet injections   needle-free injection   pneumatic jet  

摘要： Administration of exogenous hyaluronic acid (HA) by liquid jet injection is considered as a beneficial therapy for dermatology conditions. This paper reviews variety of the factors which would optimize the clinical output of hyaluronic acid in this treatment modality. A pneumatically accelerated jet penetrates the epidermis and spherically spreads micro-droplets of HA in the dermis without significant damage to the tissue and blood vessels. Kinetic energy of the jet activates two parallel mechanisms of action-mechanical and biological-which act synergistically to initiate and augment the regenerative effect. Jet-induced micro-trauma stimulates collagen synthesis and tissue repair without inflammation. Aside from the biophysical stimulation of dermal fibroblast, the biomolecular properties of exogenous HA provide excellent clinical results for skin atrophy, remodeling of dermal scarring, and reverse formation of fibrotic tissue. The effect is mediated by HA-specific cell receptors and depends on molecular weight and the rheological properties of HA polymer. Skin mechanical properties play a key role in predicting HA dispersion patterns. Tolerability and safety of the treatment approach are determined by the jet's physical impact on the tissue and/or by the safety profile of the injected material. Although pneumatic jet delivery of a hyaluronic acid has a limited use in clinical practice, this treatment approach has a strong potential for extended implementation in esthetic dermatology. The synergistic mechanism has significant advantages of predictable and rapid clinical outcomes with a low discomfort. Additional well-designed investigations are required for establishing a scientific foundation and guidelines for this treatment modality.

关键词： Absorption   Biological system modeling   Machine learning   Estimation   Vegetation mapping   Pigments   Biomedical optical imaging   Hyperspectral   leaf parameter estimation   machine learning regression  

摘要： Spectral measurements are commonly applied for the nondestructive estimation of leaf parameters, such as the concentrations of chlorophyll a and b, carotenoid, anthocyanin, brown pigment, leaf water content, and leaf mass per area for the quantification of vegetation physiology. The most popular way to estimate these parameters is by using spectral vegetation indices. The use of biochemical models allows us to use the full wavelength range (4002500 nm) and to physically interpret the result. However, their performance is usually lower than that of supervised machine learning regression techniques. Machine learning regression techniques, on the other hand, have the disadvantage that the relationship between estimated parameters and the reflectance/transmission spectra is unclear. In this article, a hybrid between a supervised learning method and physical modeling for the estimation of leaf parameters is proposed. In this method, a machine learning regression technique is applied to learn a mapping from the true hyperspectral data set to a data set that follows the PROSPECT model. The PROSPECT model then reveals the actual leaf parameters. Two mapping methods, based on Gaussian processes (GPs) and kernel ridge regression (KRR) are proposed. As an alternative, mapping onto the leaf absorption spectra is proposed as well. The proposed methodology not only estimates the leaf parameters with a lower error but also solves the interpretation problem of the parameters estimated by the advanced machine learning regression techniques. This method is validated on the ANGERS and LOPEX data set.

关键词： High resolution hyperspectral   J(max)   N:P ratio   Nutrient limitation   Physically based models   Radiative transfer   Reflectance   V-cmax  

摘要： The prediction of carbon uptake by forests across fertility gradients requires accurate characterisation of how biochemical limitations to photosynthesis respond to variation in key elements such as nitrogen (N) and phosphorus (P). Over the last decade, proxies for chlorophyll and photosynthetic activity have been extracted from hyperspectral imagery and used to predict important photosynthetic variables such as the maximal rate of carboxylation (V-cmax) and electron transport (J(max)). However, little research has investigated the generality of these relationships within the nitrogen (N) and phosphorus (P) limiting phases, which are characterised by mass based foliage ratios of N:P <= 10 for N limitations and N:P > 10 for P limitations. Using measurements obtained from one year old Pinus radiata D. Don grown under a factorial range of N and P treatments this research examined relationships between photosynthetic capacity (V-cmax, J(max)) and measured N, P and chlorophyll (Chl(a+b)). Using functional traits quantified from hyperspectral imagery we then examined the strength and generality of relationships between photosynthetic variables and Photochemical Reflectance Index (PRI), Sun-Induced Chlorophyll Fluorescence (SIF) and chlorophyll a + b derived by radiative transfer model inversion. There were significant (P < .001) and strong relationships between photosynthetic variables and both N (R-2 = 0.82 for V-cmax;R-2 = 0.87 for J(max)) and Chl(a+b) (R-2 = 0.85 for V-cmax;R-2 = 0.86 for J(max)) within the N limiting phase that were weak (R-2 < 0.02) and insignificant within the P limiting phase. Similarly, there were significant (P < .05) positive relationships between P and photosynthetic variables (R-2 = 0.50 for V-cmax;R-2 = 0.58 for J(max)) within the P limiting phase that were insignificant and weak (R-2 < 0.33) within the N limiting phase. Predictions of photosynthetic variables using Chl(a+b) estimated by model inversion were significant (P < .001), positive a

关键词： Hydroxyapatite  

摘要： Composites of hydroxyapatite (HA) and Bioglass(R)(BG) have been prepared to evaluate their physical, chemical, and biochemical characteristics. Several researchers have attempted to prepare these types of composites to combine the appealing characteristics of BG (such as high bioactivity and osteoinduction) with those of HA. The sintering temperature for the HA-BG composite system used in previous studies was >= 1200 degrees C, which yielded excessive chemical reaction between the precursors (resulting in undesirable biological characteristics), even with addition of as little as 2.5 wt.% BG. In this study, the sintering was performed at 1130 degrees C, slightly below the melting point of BG of 1200 degrees C. This lower sintering temperature prevents excessive reactions between the precursors even with BG content as high as 10 wt.%. The absence of undesirable phases (containing BG < 10 wt.%) resulted in enhanced bioactivity and moderate resorption rate.

关键词： Copper   Zinc   Tropical marine ecotoxicology   Sub-lethal toxicity   Recovery   Hormesis  

摘要： Exaiptasia pallida has been applied as a cnidarian model to assess the toxicity of various contaminants using endpoints related to growth, reproduction and mortality. However, increasingly accepted behavioural and biochemical endpoints are underrepresented in ecotoxicity testing with cnidarian species. The aim of this study was to assess the suitability of tentacle retraction and superoxide dismutase activity as behavioural and biochemical endpoints for ecotoxicity testing with E. pallida. A concentration-dependent, tentacle retraction response was found in sub-lethal toxicity testing for anemones exposed to 1-65 mu g L-1 Cu and 2-630 mu g L-1 Zn for 24 and 96 h. Semi-quantitative and quantitative approaches to tentacle retraction analysis showed a difference in response sensitivity, however, both methods resulted in similar 24- and 96-h EC50 values for Cu and Zn. Additionally, tentacle retraction analysis provided the benefit of identifying recovery in anemones previously exposed to 359 mu g L-1 Zn following a 96-h recovery period. Conversely, no significant difference in superoxide dismutase activity was detected in anemones exposed to the Cu and Zn solutions compared with controls, after either 24- or 96-h exposures. These findings support the ease of application and sensitivity of tentacle retraction as an endpoint in ecotoxicity testing with E. pallida and recommend its suitability for use in acute, sub-lethal toxicity testing. Moreover, evidence of recovery in E. pallida following exposure suggests that recovery should be incorporated into future toxicity assessments. (C) 2020 Elsevier Ltd. All rights reserved.

摘要： Cellulases have many useful applications in industry and biotechnology. So, identification of new bacterial strains expressing cellulases with better properties is desired. Five soil bacterial strains screened for high carboxymethyl cellulase (CMCase) activities were characterized and identified by 16S rRNA analysis asBacillus amyloliquefaciens(FAY088),***(FAY0103),***(FAY0117),***(FAY0136), ***(FAY0182). Their CMCase activities were 1.49, 1.26, 1.21, 1.21, and 1.24 U/ml, respectively. The maximum CMCase production was attained by growth at 35 degrees C, pH 6, and 180 rpm for 5 days. Residual activities of CMCases from FAY088 and FAY0117 were 88% or more after growth at 40 degrees C, which is same as FAY0182 CMCase at 40 and 45 degrees C. Additionally, FAY0182 retained 73% residual activity at 50 degrees C. FAY088 and FAY0182 retained more than 85% at pH 7 and 8. Conversely, residual activities from FAY0103 and FAY0136 declined a lot by increasing growth temperature beyond 40 degrees C and pH beyond 7. The maximum CMCase stability in all isolates was observed at pH 7, 3-h incubation, and 40 degrees C except for FAY0103 CMCase showed optimum temperature at 30 degrees C. More than 70% CMCase stability was retained in case of FAY088 at 50 degrees C, FAY0117 at 50-70 degrees C, and FAY0136 at 50-60 degrees C. FAY088 CMCase seemed to be the lest sensitive to temperature variation as it displayed residual activities 67, 72, 78, 84, 77, 74, and 72% at pH 3, 4, 5, 6, 8, 9, and 10, respectively. Finally, the five CMCase-producing isolates are recommended further enzyme applications in biotechnology and industry.

关键词： Ferric uptake regulator   Metal binding   DNA interactions   Aliivibrio salmonicida   Electrophoretic mobility shift assay  

摘要： Iron is an essential nutrient for bacteria, however its propensity to form toxic hydroxyl radicals at high intracellular concentrations, requires its acquisition to be tightly regulated. Ferric uptake regulator (Fur) is a metal-dependent DNA-binding protein that acts as a transcriptional regulator in maintaining iron metabolism in bacteria and is a highly interesting target in the design of new antibacterial drugs. Fur mutants have been shown to exhibit decreased virulence in infection models. The protein interacts specifically with DNA at binding sites designated as 'Fur boxes'. In the present study, we have investigated the interaction between Fur from the fish pathogenAliivibrio salmonicida(AsFur) and its target DNA using a combination of biochemical and in silico methods. A series of target DNA oligomers were designed based on analyses of Fur boxes from other species, and affinities assessed using electrophoretic mobility shift assay. Binding strengths were interpreted in the context of homology models of AsFur to gain molecular-level insight into binding specificity.