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关键词： Angkor temples   Biodeterioration   Biofilms   Capillary action   Cultural heritage   Defoliation   Sandstone   Salting   Secondary minerals  

摘要： Angkor monuments/temples in the Southeast Asia are UNESCO World Cultural Heritage of the Khmer Civilization and they require preservation and protection from destruction. In this article, activityand process-based approaches are used to present the current available results on the active microorganisms and their biochemical processes associated with the biodeterioration of sandstone cultural heritage under the tropical climate in Cambodia. Such information is important for effectively protection and management. Severe deterioration of sandstone monuments is a result of weathering processes of a combination of physical, chemical and biological forces, including both natural and anthropogenic ones. Given the fact that water is an important natural factor affecting the stability of sandstone cultural heritage under the tropical regions, subsequent microbial colonization and contribution to the deterioration of sandstone have been investigated with both culture-dependent and culture-independent techniques to provide information about the microbiota associated with the sandstone. Recent data show that both sulfur and nitrogen cycles are active biochemical processes by specific microorganisms on sandstone temples/monuments in the tropical region. Both sulfur-oxidizing bacteria and fungi are active involved and, more recently, ammonia-oxidizing archaea (AOA) are implicated with higher abundance than ammonia-oxidizing bacteria (AOB) on sandstone monuments. It is clear that a research paradigm shift is taking place on microbiology of cultural heritage, and the active, and biochemically and physiologically functional microbes are focused to advance our fundamental understanding and knowledge on the biodeteriogens for a better protection and management of cultural heritage. Biochemically and physiologically functional and important microorganisms, as well as the biochemical mechanisms involved, shall be focused in order to advance the basic research on cultural heritage, while

关键词： Blood parameters   Serum biochemistry   Sex   Season   Schizothorax labiatus   Sindh River  

摘要： Snow trout Schizothorax labiatus constitute a significant part of the diet of large human population of colder regions of the Indian Himalayan subcontinent, and are also important for local livelihoods there. In the present study, the hematological and serum biochemical parameters of S. labiatus were examined with respect to sex and season. Hemoglobin (Hb) concentration, red blood cell (RBC) count and hematocrit (Hct) were higher in males than females in each season, while white blood cell (WBC) count were notably higher in females. A significant difference (P < 0.05) was noted in Hb concentration, RBC and WBC counts, and Hct between males and females during the summer compared to the other seasons. There was no significant difference (P > 0.05) between erythrocyte indices with respect to sex and season. Serum biochemical parameters (glucose, cholesterol and urea) differed significantly (P < 0.05) between the sexes, as well as among the seasons. However, no significant differences (P > 0.05) were observed in biochemical parameters (total protein, albumin and globulin) with respect to sex, although the highest values of all serum biochemical parameters were reported during the summer and the lowest values during the winter. The data reported here on the influence of sex and season on hematological and biochemical parameters of S. labiatus inhabiting the Sindh River could provide a reliable basis for the future monitoring of the health status of this fish.

关键词： Bayes&apos   theorem   fetal growth restriction   first‐   trimester screening   likelihood   mean arterial pressure   placental growth factor   pregnancy‐   associated plasma protein‐   A   pyramid of prenatal care   SGA   survival model   uterine artery Doppler  

摘要： Objective To develop a new competing-risks model for the prediction of a small-for-gestational-age (SGA) neonate, based on maternal factors and biophysical and biochemical markers at 11-13 weeks' gestation. Methods This was a prospective observational study in 60 875 women with singleton pregnancy undergoing routine ultrasound examination at 11 + 0 to 13 + 6 weeks' gestation. All pregnancies had pregnancy-associated plasma protein-A and placental growth factor (PlGF) measurements, 59 001 had uterine artery pulsatility index (UtA-PI) measurements and 58 479 had mean arterial pressure measurements;57 131 cases had complete data for all biomarkers. We used a previously developed competing-risks model for the joint distribution of gestational age (GA) at delivery and birth-weight Z-score, according to maternal demographic characteristics and medical history. The likelihoods of the biophysical markers were developed by fitting folded-plane regression models, a technique that has already been used in previous studies for the likelihoods of biochemical markers. The next step was to modify the prior distribution by the likelihood, according to Bayes' theorem, to obtain individualized distributions for GA at delivery and birth-weight Z-score. We used the 57 131 cases with complete data to assess the discrimination and calibration of the model for predicting SGA with, without or independently of pre-eclampsia, by different combinations of maternal factors and biomarkers. Results The distribution of biomarkers, conditional to both GA at delivery and birth-weight Z-score, was best described by folded-plane regression models. These continuous two-dimensional likelihoods update the joint distribution of birth-weight Z-score and GA at delivery that has resulted from a competing-risks approach;this method allows application of user-defined cut-offs. The best biophysical predictor of preterm SGA was UtA-PI and the best biochemical marker was PlGF. The prediction of SGA was consisten

关键词： Maize   BLSB   Resistance   Enzymatic activity   Inbreds  

摘要： Maize (Zea mays L.) is a staple food in many parts of the world. In addition to being used as grain, animal feed, production of corn ethanol, starch, syrup etc., it has been widely consumed as a vegetable in the form of baby corn and sweet corn. Banded leaf and sheath blight (BLSB) is one of the major diseases affecting maize and is caused by Rhizoctonia solani f. sp. sasakii Exner. In the experiment forty six maize inbreds were screened for their reaction against the BLSB pathogen following artificial inoculation. Two inbred lines namely, EV1417 and CML-323 produced resistant and moderately resistant disease reaction respectively. Biochemical studies indicated the presence of a high level of pre-infectional barriers in the resistant line. Further, higher level of defense related enzymatic activities of peroxidase and poly phenol oxidase were detected in the resistant inbred line. After 48 h of inoculation, in comparison to highly susceptible EV1428, electrolyte leakage was found to be stabilized in EV1417 and CML-323. This study clearly establishes the presence of effective pre-infection barriers and induced biochemical defence mechanisms operating in the resistant inbred line. The identified resistant line EV1417 is further being used in BLSB disease resistance breeding programmes.

关键词： biochemical analytes   chickens   cytokines   high Ca   high-protein diet   histopathology   Urolithiasis  

摘要： This study was carried out to evaluate the effects of induced urolithiasis by high dietary calcium (Ca) or protein levels on biochemical analyte levels, redox status, selected inflammatory cytokines and histopathology in chickens. A total of 90 one-day-old white Hy-Line chicks were fed basal control diets containing 20% crude protein (CP) and 1% Ca until they reached 44 days of age. After that, the birds were divided into three groups (30 birds per group). All management factors (light, temperature, ventilation, stock density and diet) were identical among the three groups throughout the study except for the dietary Ca and protein percentages. Group I was fed a control diet containing 20% CP and 1% Ca, group II was fed a high-Ca diet containing 5% Ca, and group III was fed a high-protein diet containing 25% CP. Our findings clearly demonstrated that dietary imbalance (caused by high-Ca or high-CP levels) per se in chickens was physiologically harmful, as it was accompanied by post-mortem lesions;biochemical, redox status and histopathological alterations;and upregulation of inflammatory cytokines (interleukin (IL)-1 beta and IL-6). In particular, the birds fed the high-Ca diet clearly exhibited the most obvious alterations in most of the endpoints. In conclusion, this study constitutes the first extensive investigation of the effects of high-Ca or high-protein diets induced urolithiasis on growth performance, redox status, inflammatory cytokine levels and pathological characterization in chickens.

关键词： B. Variegata   Phytochemicals   HPLC   Antioxidants   Hepatoprotective effect  

摘要： Liver disorders may occur as a result of exposure to chemical compounds capable of inducing the oxidative stress and hepatic injuries. The aim of present study was to investigate the effects of flower extracts of B. Variegata for the treatment of liver injury induced by the CCl4. About 1 ml/kg body weight (b.w) of CCl4 was induced to experimental mice by intraperitoneal way for 14 days. The methanol and chloroform extracts (100, 200 and 300 mg/kg b.w) were administered to experimental animals for 14 days along with standard drug Silymarine (100 mg/kg b.w). The extracts alone showed no evidence of hepatic toxicity but animals exposed to CCl4 without the treatment with B. Variegata presented variations in levels of liver enzymes, antioxidant enzymes, proteins and blood cells as well as injuries in liver cells were also observed during histopathological study. However, after the treatments especially with 300 mg/kg b.w of methanol flower extracts levels of liver markers (ALT, AST and ALP), antioxidant enzymes and blood cells decreases and turned towards normal levels. Whereas level of total proteins and bilirubin was improved and damaged liver cells were repaired. The curative activity of flower extracts can be correlated to the higher potential of antioxidants and occurrence of Quercetin and some other organic compounds those were investigated from flower extracts of B. Variegata during HPLC and GC-MS analysis. The finding of this study supports the use of B. Variegata flower formulation in folk medicines. (C) 2020 The Authors. Published by Elsevier B.V. on behalf of King Saud University.

关键词： Apoptosis   Histopathology   Lipid peroxidation   Morphometry   Nandrolone decanoate   Prostate   Seminal vesicles  

摘要： Nandrolone decanoate (Nd) is a highly abused androgenic-anabolic steroid among body builders. Even though it has weak androgenic effects, its prolonged use may have harmful impact on male reproductive system which needs to be evaluated. This study aimed to reinvestigate its possible oxidative stress induced alteration on male rat reproductive system. Twenty-eight male rats were divided into two groups. Nd treated group (n = 18) injected intramuscular with 10 mg/kg body weight once a week for four weeks. While, the control group (n = 10) was injected with physiologic saline by the same route for four weeks. Body weight was recorded for all rats and after animal dissection weight of testes, prostate and seminal vesicles were also recorded. The results showed that the average testicular weight was decreased in treated group compared to the control. The average weights of the prostate and seminal vesicles were increased compared to the control. Morphometric study revealed that in Nd treated group, there was a decrease in the width of seminiferous tubules and the height of spermatogenic cell layer compared to the control. Testicular degeneration was expressed by presence of spermatid giant cells, vacuolation, and degenerated spermatozoa. Tunnel technique showed scattered positive reaction among the spermatogenic cell layers and interstitial cells. Severe alterations of the prostate were expressed by benign prostate hyperplasia and retained secretions. Lipid peroxidation products (malonaldehyde concentration as ng/g of testicular tissue) were increased in treated group compared to the control and suggested the occurrence of oxidative damage. Nd induced severe alterations in the male genital organs were resulted from oxidative stress. It is concluded that the male genital organs are highly sensitive to the anabolic steroids and there is a high extent of reproductive risk associated with the use of AASs. (C) 2020 The Author. Published by Elsevier B.V. on behalf of King Saud

关键词： Amidases   Thauera   Cloning   Characterization  

摘要： A novel amidase (TAM) was identified and cloned from the genome of Thauera sinica K11. The recombinant protein was purified to homogeneity by one-step affinity chromatography for up to 26.4-fold with a yield of 38.1%. Gel filtration chromatography and SDS-PAGE revealed that the enzyme was a tetramer with a subunit of approximately 37.5 kDa. The amidase exhibited the maximum acyl transfer activity at 45 degrees C and pH 7.0, and it was highly stable over a wide pH range of 6.0-11.0. Inhibition of enzyme activity was observed in the presence of metal ions, thiol reagents and organic solvents. TAM showed a broad substrate spectrum toward aliphatic, aromatic and heterocyclic amides. For linear aliphatic monoamides, the acyl transfer activity of TAM was decreased with the extension of the carbon chain length, and thus the highest activity of 228.2 U/mg was obtained when formamide was used as substrate. This distinct selectivity of amidase to linear aliphatic monoamides expanded the findings of signature amidases to substrate specificity.

关键词： Hemolymph   Hemocytes   Biomimetic   Scaffolds   Biomaterials   Biomineralization  

摘要： Molluscan hemolymph is a unique kind of body fluid, which in many respects is analogous to human blood, although there are several crucial differences. Here, for the first time, we critically analyze the prospects for applications of this fluid in modern biomaterials science. Particular attention is paid to the biochemistry and chemistry of molluscan hemolymph, as well as to hemocytes and hemocyanins as key functional players within this unique biological fluid. We focus on hemocytes as multifunctional hemolytic cells involved in immune response, and especially in the biomineralization process. The next part of the review contains a discussion of molluscan shell formation and regeneration from different points of view. Finally, we consider the challenges, solutions, and future directions in the application of molluscan hemolymph for bioinspired material chemistry and biomedicine.

关键词： Amphibians   Pesticides   Neurotoxicity   Oxidative stress   Mortality   Biomonitoring  

摘要： Insecticides used for agricultural pest control, as cypermethrin-based insecticide (CBI) and fipronil-based insecticide (FBI), are constant threats to non-target aquatic organisms. This study aimed to investigate the effect of different concentrations of cypermethrin and fipronil on neurotoxicity and oxidative stress inPhysalaemus *** gracilistadpoles were exposed to five insecticide concentrations and a control treatment, with six replicates. During the experimental period, the tadpole mortality rate was evaluated and after 168 h, the neurotoxic enzyme activity and metabolite quantification related to the antioxidant system were measured. Tadpoles reduced acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities when exposed to 20 mu g L-1CBI and at all FBI concentrations, respectively. Glutathione S-transferase (GST) and superoxide dismutase (SOD) activities showed an increase from concentrations of 6 mu g L(-1)and 20 mu g L(-1)of CBI, respectively. After exposure ofP. gracilistadpoles to FBI, inhibitions of AChE and BChE were observed at the highest concentrations evaluated (500 and 1500 mu g L-1). SOD activity decreased from 50 mu g L(-1)of FBI;however, catalase (CAT) and GST activities and carbonyl protein levels increased, regardless of the evaluated dose. We observed that both insecticides promoted oxidative stress and neurotoxic effects inP. gracilistadpoles. These results suggest that biochemical biomarkers can be used for monitoring toxicity insecticides for the purpose of preservation ofP. gracilis.