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关键词： Temperature stress   Seagrass   Halodule pinifolia   Net photosynthesis   Dark respiration   Metabolomics   Sugars   Aminoacids   TROPICAL SEAGRASSES   PLANT   TEMPERATURE   MEMBRANE   STRESS   GROWTH   PHOTOSYNTHESIS   ACCLIMATION   TOLERANCE  

摘要： Seagrasses are submerged marine angiosperms often prone to various biotic and abiotic stress factors in the marine environment. Our study investigated the response, adaptation and underlying tolerance mechanism of tropical seagrass Halodule pinifolia upon temperature stress (24 degrees, 29 degrees, 37 degrees, and 45 degrees C) and evaluated the effect of temperature stress on net photosynthesis (Delta F/F-m') and dark respiration (F-v/F-m). In this study, metabolomic analysis of seagrass H. pinifolia upon heat stress has been performed using GC-MS based omics approach. As a result, the net photosynthetic efficiency (Delta F/F-m') was found significantly decreased upon heat stress, while the dark respiration rate was increased to 2.903 mg O-2/g FW h(-1) and 3.87 mg O-2/g FW h(-1) as compared to the control (24 degrees C), respectively. Metabolomic analysis showed heat stress could cause large metabolite variations with respect to sugar, amino acids and organic acids. Interestingly, three thermo-protective metabolites such as trehalose (sugar), glycine betaine (amino acid) and methyl vinyl ketone (organic acid) were profiled from H. pinifolia (45 degrees C) and is the first report on the occurrence of glycine betaine and methyl vinyl ketone from seagrasses and other aquatic species so far. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis demonstrated H. pinifolia exposed to heat stress lead to intense biochemical changes and caused significant variations in the heat responsive metabolic pathways. The present findings would facilitate the further research on identifying gene to metabolite networks for an effective management of seagrass conservation by genetic manipulation.

关键词： Diphenyl carbonate   THP1 cell line   Biochemical assessment   Carbopol   Hydrogel   Oxidative stress   CYCLODEXTRIN-BASED NANOSPONGES   NANOSTRUCTURED LIPID CARRIERS   OXIDATIVE STRESS   IN-VITRO   DRUG-RELEASE   EFFICACY   NANOPARTICLES   GEL   BIOAVAILABILITY   PHOTOSTABILITY  

摘要： Clobetasol propionate (CP), a superpotent topical corticosteroid, holds great promise for psoriasis treatment. However, common side effects like skin atrophy, steroidal acne, hypopigmentation and allergic contact dermatitis associated with it, hamper its utility for topical application. Taking this into consideration, the current work was aimed to fabricate CP loaded cyclodextrin nanosponge (CDNS) based hydrogel, to alleviate the aforementioned side effects, while controlling drug release. Nanosponges were crafted employing beta-cyclodextrin (polymer) and diphenyl carbonate (cross linker) and evaluated appropriately. The selected formulation augmented 45 folds water solubility, with respect to pure CP. The formulation possessed entrapment efficiency (56.33 +/- 0.94%), particle size (194.27 +/- 49.24 nm) with polydispersitive index (0.498 +/- 0.095), surface charge (-21.83 +/- 0.95 mV) and drug release (86.25 +/- 0.28%). Selected CP-CDNS were found crystalline and uniform in size. Further, in vitro cell viability analysis has been performed using THP1 cells to evaluate cytocompatibility of CP nanosponges. The chosen CP nanosponges were then embedded into Carbopol hydrogel, and characterized for rheological behaviour, spreadability, and texture profile. The developed nanoformulations were also assessed in vivo using mouse tail model. Histological and biochemical assessments have been conducted to explore their antipsoriatic activity via oxidative stress biomarkers. The degree of orthokeratosis was observed remarkably (p < 0.001) amplified by CP-CDNS14 hydrogel as compared to untreated group (control) and CP hydrogel. In addition, drug activity and change in epidermal thickness were found significant. Our findings altogether advocated the profound potential of prepared CP nanogel in the topical treatment of psoriasis, with improved patient compliance.

关键词： Dentine caries   Infected dentine   Affected dentine   Raman spectroscopy   Amide I   Phosphate   Knoop microhardness   Minimally invasive dentistry   CARIES REMOVAL   2 LAYERS   IN-VIVO   MICROHARDNESS   ENAMEL   SYSTEM  

摘要： Objective: Carious tissue discrimination in clinical operative caries management relies traditionally on the subjective hardness of carious dentine. Biochemical alterations within the lesion have the potential to discriminate the lesion zones objectively. This study aimed to determine the correlation between the biochemical proportions of amide I and phosphate moieties as these are the most prominent peaks found in dentine with the Knoop microhardness of carious dentine zones, using non-contact Raman spectroscopy. The null hypothesis investigated was that there was no correlation between Raman peak ratios, amide I: phosphate nu 1, and the Knoop micro hardness within specific zones of a carious lesion. Methods: 423 scan points from 20 carious dentine lesion samples examined using high-resolution Raman spectroscopy. The peak ratio of the characteristic vibration mode of amide I (1650 cm(-1)) and phosphate (960 cm(-1)) bands were calculated, following a straight line path through the lesion to the pulp and correlated to corresponding Knoop microhardness measurements. Results: Using logistic regression analysis, clear correlations were found between the Knoop microhardness and Raman peak ratio cut-off values between caries-infected and caries-affected dentine (81.5 % sensitivity / 92.7 % specificity), with a lower specificity (2.7 %) found between caries-affected and sound dentine. Conclusion: This study concluded that non-contact Raman spectroscopy can be used in vitro to discriminate objectively between the different zones of a carious dentine lesion at high resolution, using the Raman peak ratios, amide I : phosphate nu 1. Clinical Significance: Specific biochemical alterations have the potential to be used in-vitro and in-vivo to identify the end-point of selective carious lesion excavation.

关键词： Bidens pilosa L.   Hyperaccumulator   Ecotype   Phytoremediation   SOLANUM-NIGRUM L.   SEDUM-ALFREDII   HYPERACCUMULATING ECOTYPE   CONTRASTING ECOTYPES   METAL TOLERANCE   CD   EXPRESSION   ATPASE   POLLUTION   STRESS  

摘要： Bidens pilosa L. is a widely distributed Cd-hyperaccumulator species in the world with large biomass and fast growth rate. The Cd accumulating differences between different ecotypes of B. pilosa is not clear. This experiment firstly compared the Cd concentrations and relative physio-biochemical indices using two B. pilosa ecotypes collected from clean soils. The results showed that the Cd concentrations of stems and leaves of Hanzhong ecotype of B. pilosa (HZ) and Shenyang ecotype (SY) were all higher than their root Cd concentrations in different Cd concentration gradient experiment (from 2.57 mg kg(-1) to 37.17 mg kg(-1) in soils). Cd concentrations of the roots, stems and leaves of HZ and SY were all higher than in the soils either. However, HZ accumulated higher Cd concentrations than SY, i.e. roots increased by 32.7-45.8%, stems increased by 32.3-46.6% and leaves increased by 33.4-68.4%, respectively. Furthermore, the biomasses of HZ were all higher than the SY either. Compared to SY, higher Cd accumulation of HZ might be relevant with its higher photosynthetic pigment content, stomatal conductance, intercellular CO2 concentration, some antioxidant enzyme activities, H+-ATPase, Ca2+-ATPase and 5'-AMPase activities, and lower malondialdehyde (MDA) content. Particularly, the changes of extractable Cd concentrations in rhizospheric soils of HZ and SY were corresponding to their Cd concentrations. Considering the two different ecotypes of HZ and SY were all collected from different clean farmlands, the new foundings that different mechanisms of HZ and SY accumulating Cd from the soil might be very important for screening and constructing ideal hyperaccumulator aimed at improving phytoremediation capacities in the future.

关键词： Glutaric acid   Lysine   Glutaric aciduria   Inbred mouse strains   Mouse genetics   LYSINE  

摘要： The glutaric acidurias are a group of inborn errors of metabolism with different etiologies. Glutaric aciduria type 3 (GA3) is a biochemical phenotype with uncertain clinical relevance caused by a deficiency of succinyl-CoA: glutarate-CoA transferase (SUGCT). SUGCT catalyzes the succinyl-CoA-dependent conversion of glutaric acid into glutaryl-CoA preventing urinary loss of the organic acid. Here, we describe the presence of a GA3 trait in mice of 129 substrains due to SUGCT deficiency, which was identified by screening of urine organic acid profiles obtained from different inbred mouse strains including 129S2/SvPasCrl. Molecular and biochemical analyses in an F2 population of the parental C57BL/6J and 129S2/SvPasCrl strains (B6129F2) confirmed that the GA3 trait occurred in Sugct129/129 animals. We evaluated the impact of SUGCT deficiency on metabolite accumulation in the glutaric aciduria type 1 (GA1) mousemodel. We found that GA1 mice with SUGCT deficiency have decreased excretion of urine 3-hydroxyglutaric acid and decreased levels glutarylcarnitine in urine, plasma and kidney. Our work demonstrates that SUGCT contributes to the production of glutaryl-CoA under conditions of low and pathologically high glutaric acid levels. Our work also highlights the notion that unexpected biochemical phenotypes can occur in widely used inbred animal lines. (C) 2021 Elsevier Inc. All rights reserved.

关键词： Continuous-time Markov jump processes   Master equation   Completion time statistics   Substrate inhibition in enzymatic catalysis   Stochastic gene expression   MODELS   EXPRESSION  

摘要： Continuous-time stationary Markov jump processes among discrete sites are encountered in disparate biochemical ambits. Sites and connecting dynamical events form a 'network' in which the sites are the available system's states, and the events are site-to-site transitions, or even neutral processes in which the system does not change site but the event is however detectable. Examples include conformational transitions in single biomolecules, stochastic chemical kinetics in the space of the molecules copy numbers, and even macroscopic steady-state reactive mixtures if one adopts the viewpoint of a tagged molecule (or even of a molecular moiety) whose state may change when it is involved in a chemical reaction. Among the variety of dynamical descriptors, here we focus on the first occurrence times (starting from a given site) and on the recurrence times of an event of interest. We develop the sensitivity analysis for the lowest moments of the statistical distribution of such times with respect to the rate constants of the network. In particular, simple expressions and inequalities allow us to establish a direct relationship between selective variation of rate constants and effect on average times and variances. As illustrative cases we treat the substrate inhibition in enzymatic catalysis in which a tagged enzyme molecule jumps between three states, and the basic two-site model of stochastic gene expression in which the single gene switches between active and inactive forms.

关键词： Coronavirus disease 2019 (COVID-19)   Bacterial pneumonia   Influenza   Differential diagnosis   Prospective grading   EOSINOPENIA   MARKER  

摘要： We evaluated simple laboratory variables to discriminate COVID-19 from bacterial pneumonia or influenza and for the prospective grading of COVID-19. Multivariate logistic regression and receiver operating characteristic curve were used to estimate the diagnostic performance of the significant discriminating variables. A comparative analysis was performed with different severity. The leukocytosis (P = 0.017) and eosinopenia (P = 0.001) were discriminating variables between COVID-19 and bacterial pneumonia with area under the curve (AUC) of 0.778 and 0.825. Monocytosis (P = 0.003), the decreased lymphocyte-to-monocyte ratio (P < 0.001), and the increased neutrophil-to-lymphocyte ratio (NLR) (P = 0.028) were predictive of influenza with AUC of 0.723, 0.895, and 0.783, respectively. Serum amyloid protein, lactate dehydrogenase, CD3(+) cells, and the fibrinogen degradation products had a good correlation with the severity of COVID-19 graded by age (>= 50) and NLR (>= 3.13). Simple laboratory variables are helpful for rapid diagnosis on admission and hierarchical management of COVID-19 patients. (C) 2020 Elsevier Inc. All rights reserved.

关键词： Cadmium   Abscisic acid   Antioxidative systems   Vigna radiata(L   ) R   Wilczek   ANTIOXIDANT DEFENSE SYSTEM   L. WILCZEK SEEDLINGS   HEAVY-METAL STRESS   OXIDATIVE STRESS   SALICYLIC-ACID   GLUTATHIONE METABOLISM   PROLINE ACCUMULATION   MOLECULAR-MECHANISMS   SUPEROXIDE-DISMUTASE   ARABIDOPSIS-THALIANA  

摘要： Experiments were conducted to determine how exogenous abscisic acid (ABA) mediates the tolerance of plants to cadmium (Cd) exposure. Cd stress strongly reduced all the growth parameters of mung bean seedlings. Cd significantly increased ascorbate peroxidase (APX) and catalase (CAT) activities in roots and stems, and peroxidase (POD) activities in roots, stems, and leaves of mung bean seedlings. Cd caused remarkable increases in the levels of leaf chlorophyll and carotenoid, root polyphenols, and malondialdehyde (MDA) and proline in the three organs. However, Cd greatly decreased leaf CAT activity, root and leaf ascorbic acid (AsA) levels, and stem and leaf polyphenol levels. Foliar application of ABA partially alleviated Cd toxicity on the seedlings. ABA could restore most of the changed biochemical parameters caused by Cd, suggesting that ABA played roles in the protection of membrane lipid peroxidation and the modulation of antioxidative defense systems in response to Cd stress. Our results also implied the differential physiological and biochemical responsive patterns of roots, stems, and leaves to Cd and ABA in mung bean seedlings. The great changes in many biochemical parameters in roots suggested that roots were the first to be affected by Cd and play pivotal roles in response to Cd, especially in chelating Cd and reducing Cd absorption.

关键词： Methotrexate   Neurotoxicity   Nephrotoxicity   Hepatotoxicity   Apoptosis   Oxidative stress   LOW-DOSE METHOTREXATE   INDUCED OXIDATIVE STRESS   RHEUMATOID-ARTHRITIS   INDUCED HEPATOTOXICITY   CHLOROGENIC ACID   RENAL TOXICITY   CELL-CYCLE   APOPTOSIS   DAMAGE   EXPRESSION  

摘要： Methotrexate (MTX) has been used for treatment of autoimmune diseases, inflammatory disorders as rheumatic arthritis, and different types of cancers. However, it has shown adverse effects on vital organs. The current study was conducted to investigate the toxic effect of MTX on the hippocampus, cerebellum, liver and kidneys of adult male albino rats. MTX was injected weekly at 5 mg/kg body weight via I/P injection for 6 weeks. At the end of the experiment, histopathological, immunohistochemical and biochemical evaluation were performed on the hippocampus, cerebellum, liver, and kidney tissues of the sacrificed rats. We observed that methotrexate induced neural tissue damage in the hippocampus and cerebellum, degeneration of hepatocytes, congestion of the central vein and blood sinusoids of the liver, distortion in the renal corpuscles and necrosis of the renal tubule. Immunohistochemical findings revealed strong positive expression of Caspase-3, PCNA and GFAP. Biochemical studies revealed significant elevation in the serum levels of AST and ALT, in addition to high serum concentrations of creatinine and urea. Also, MTX injection increased MDA, while it decreased GSH, SOD and AChE levels. We conclude the ability of MTX to induce oxidative stress that results into apoptosis and tissue injury, leading to neurotoxicity, hepatotoxicity, and nephrotoxicity.

关键词： CARCINOMA  

摘要： Purpose Using conditional survival (CS) analysis, we investigated whether the duration of survival without biochemical recurrence (BCR) of prostate cancer after laparoscopic radical prostatectomies (LRP) affected the BCR rate. We also investigated the impact of well-known risk factors for BCR. Methods Between 2002 and 2014, 627 consecutive patients underwent LRPs at our institution. Prostate-specific antigen (PSA) concentrations above 0.2 ng/mL were defined as BCR. Conditional BCR-free survival rates were determined through Kaplan-Meier analysis. Assessment of potential BCR risk factors was performed using a Cox proportional hazard analysis. Results The 10-year BCR-free rates after LRP increased to 82.4%, 84.5%, 86.6%, 90.1%, and 94.7% in patients surviving 1, 2, 3, 5, and 7.5 years without BCR, respectively. Multivariate analyses of age, PSA concentrations, neoadjuvant therapy, and pathological findings were performed for all patients. In all patients, positive surgical margins (PSM) and Gleason Grade Groups (GG) >= 4 were independent risk factors for BCR (p < 0.001, hazard ratio [HR] = 2.45; andp < 0.001, HR = 2.83, respectively,). Similarly, PSM and GG >= 4 were significant risk factors in patients surviving 1-5 years without BCR. No clear risk factors were observed in patients surviving > 5 years without BCR after LRPs. Conclusions The BCR-free rate increased with time after LRP. It is recommended that patients with PSM, GG >= 4, or with both factors are strictly monitored for 5 years postoperatively. CS analysis is particularly useful for predicting the postoperative course of patients.