Amino acid application inhibits root-to-shoot cadmium translocation in Chinese cabbage by modulating pectin methyl-esterification.

The exogenous application of amino acids (AAs) generally alleviates cadmium (Cd) toxicity in plants by altering their subcellular distribution. However, the physiological mechanisms underlying AA-mediated cell wall (CW) sequestration of Cd in Chinese cabbage remain unclear. Using two genotypes of Chinses cabbage, Jingcui 60 (Cd-tolerant) and 16-7 (Cd-sensitive), we characterized the root structure, subcellular distribution of Cd, CW component, and related gene expression under the Cd stress. Cysteine (Cys) supplementation led to a reduction in the Cd concentration in the shoots of Jingcui 60 and 16-7 by 65.09 % and 64.03 %, respectively. Addition of Cys alleviated leaf chlorosis in both cultivars by increasing Cd chelation in the root CW and reducing its distribution in the cytoplasm and organelles. We further demonstrated that Cys supplementation mediated the downregulation of PMEI1 expression and improving the activity of pectin methyl-esterase (PME) by 17.98 % and 25.52 % in both cultivars, respectively, compared to the Cd treatment, resulting in an approximate 12.00 %-14.70 % increase in Cd retention in pectin. In contrast, threonine (Thr) application did not significantly alter Cd distribution in the shoots of either cultivar. Taken together, our results suggest that Cys application reduces Cd root-to-shoot translocation by increasing Cd sequestration in the root CW through the downregulation of pectin methyl-esterification.

Foliar zinc spraying improves assimilative capacity of sugar beet leaves by promoting magnesium and calcium uptake and enhancing photochemical performance.

Sugar beet, a zinc-loving crop, is increasingly limited by zinc deficiency worldwide. Foliar zinc application is an effective and convenient way to supplement zinc fertilizer. However, the regulatory mechanism of foliar zinc spraying on sugar beet leaf photosynthetic characteristics remains unclear. Therefore, we investigated the effects of foliar ZnSO4·7H2O application (0, 0.1%, 0.2%, and 0.4%) on the photosynthetic performance of sugar beet leaves under controlled hydroponic conditions. The results indicated that a foliar spray of 0.2% Zn fertilizer was optimal for promoting sugar beet leaf growth. This concentration significantly reduced the leaf shape index of sugar beet, notably increasing leaf area, leaf mass ratio, and specific leaf weight. Foliar spraying of Zn (0.2%) substantially elevated the Zn content in sugar beet leaves, along with calcium (Ca) and magnesium (Mg) contents. Consequently, this led to an increase in the potential photochemical activity of PSII (Fv/Fo) (by 6.74%), net photosynthetic rate (Pn) (11.39%), apparent electron transport rate (ETR) (11.43%), actual photochemical efficiency of PSⅡ (Y (Ⅱ)) (11.46%), photochemical quenching coefficient (qP) (15.49%), and total chlorophyll content (25.17%). Ultimately, this increased sugar beet leaf dry matter weight (11.30%). In the cultivation and management of sugar beet, the application of 0.2% Zn fertilizer (2.88 mg plant-1) exhibited the potential to enhance Zn and Mg contents in sugar beet, improve photochemical properties, stimulate leaf growth, and boost light assimilation capacity. Our result suggested the foliar application of Zn might be a useful strategy for sugar beet crop management.

Characterization of Root and Foliar-Applied Iron Oxide Nanoparticles (α-Fe2O3, γ-Fe2O3, Fe3O4, and Bulk Fe3O4) in Improving Maize (Zea mays L.) Performance.

Iron (Fe) oxide nanoparticles (NPs) improve crop growth. However, the comparative effect of root and foliar-applied different sources of Fe oxide NPs on plant performance at morphological and physiological levels still needs to be discovered. In this study, we characterized the growth and physiological responses of hydroponic-cultured maize seedlings to four sources of Fe (i.e., α-Fe2O3, γ-Fe2O3, Fe3O4 NPs, and bulk Fe3O4) and two application methods (root vs. foliar). Results showed that Fe concentration in root and shoot increased by elevating the level of NPs from 100 mg L-1 to 500 mg L-1. Overall, the responses of maize seedlings to different sources of Fe oxide NPs were as follows: Fe3O4 > γ-Fe2O3 > α-Fe2O3 > bulk Fe3O4. The application of Fe at concentrations ranging from 100 mg L-1 to 500 mg L-1 had no significant effects on various growth parameters of maize, including biomass, chlorophyll content, and root length. Iron oxide NPs increased the plant biomass by 23-37% by root application, whereas it was 5-9% by foliar application. Chlorophyll contents were increased by 29-34% and 18-22% by foliar and root applications, respectively. The non-significant response of reactive oxygen species (i.e., superoxide dismutase, catalase, and peroxidase) suggested optimum maize performance for supplementing Fe oxide NPs. A confocal laser scanning microscope suggested that Fe oxide NPs entered through the epidermis and from the cortex to the endodermis. Our results provide a scientific basis that the root application of Fe3O4 at the rate of 100 mg L-1 is a promising approach to obtain higher maize performance and reduce the quantity of fertilizer used in agriculture to minimize environmental effects while improving crop productivity and quality. These findings demonstrated the tremendous potential of Fe NPs as an environmentally friendly and sustainable crop approach.

Polypharmacology-based approach for screening TCM against coinfection of Mycoplasma gallisepticum and Escherichia coli.

Natural products and their unique polypharmacology offer significant advantages for finding novel therapeutics particularly for the treatment of complex diseases. Meanwhile, Traditional Chinese Medicine exerts overall clinical benefits through a multi-component and multi-target approach. In this study, we used the previously established co-infection model of Mycoplasma gallisepticum and Escherichia coli as a representative of complex diseases. A new combination consisting of 6 herbs were obtained by using network pharmacology combined with transcriptomic analysis to reverse screen TCMs from the Chinese medicine database, containing Isatdis Radix, Forsythia Fructus, Ginkgo Folium, Mori Cortex, Licorice, and Radix Salviae. The results of therapeutic trials showed that the Chinese herbal compounds screened by the target network played a good therapeutic effect in the case of co-infection. In summary, these data suggested a new method to validate target combinations of natural products that can be used to optimize their multiple structure-activity relationships to obtain drug-like natural product derivatives.

Effect of Curcumin as Feed Supplement on Immune Response and Pathological Changes of Broilers Exposed to Aflatoxin B1.

In this study, we examined the protective effects of curcumin against the AFB1-induced immune response of and pathological changes in broilers. Histopathology examinations showed that at day 28, AFB1 (5 mg/kg) exposure leads to severe histological changes in the spleen, thymus and bursa of Fabricius with a decrease in the number and karyoplasmic area ratio of plasma cells. Curcumin alleviated the AFB1-induced immune organs' damage as well as the changes in plasma cells in a dose-dependent manner. RT-PCR data showed that AFB1 significantly downregulated the IL-2 and IFN-γ mRNA expression levels in the thymus, spleen and bursa of Fabricius. However, curcumin supplementation improved the AFB1-induced immune organs' damage via upregulated cytokines' expression. Intriguingly, similar trends were noticed in abnormal morphological changes and the immune response at day 35 after the withdrawal of AFB1 and curcumin from the diet, suggesting the protective effects and immunomodulatory function against AFB1 in broilers. The current study provides a scientific experimental basis for the application of curcumin as a therapeutic drug or additive in animal husbandry productive practice.

Effects of Lactobacillus salivarius supplementation on the growth performance, liver function, meat quality, immune responses and Salmonella Pullorum infection resistance of broilers challenged with Aflatoxin B1.

Aflatoxin B1 (AFB1) is one of the most toxic mycotoxins. It has been reported that dietary exposure to AFB1 is related to the low growth performance, immunosuppression, and high susceptibility to infectious diseases of chickens. The aim of the present study was to evaluate the protective effects of Lactobacillus salivarius on broiler chickens challenged with AFB1. First, AFB1 degradation ability of Lactobacillus salivarius was measured by a high-performance liquid chromatography (HPLC) method. Then, the Arbor Acres broiler chickens were randomly assigned to experimental groups. The effects of Lactobacillus salivarius supplementation on the growth performance, liver function, and meat quality were measured, and immune response was also determined after vaccination with attenuated infectious bursal disease virus (IBDV) vaccine of broilers challenged with AFB1. Besides, resistance to Salmonella Pullorum infection along with AFB1 exposure was determined in broilers. The results showed that Lactobacillus salivarius could effectively degrade AFB1. Lactobacillus salivarius supplementation improved growth performance, liver function, and meat quality of broilers challenged with AFB1. In addition, Lactobacillus salivarius supplementation resulted in enhanced specific antibody and IFN-γ production, and lymphocyte proliferation in broilers challenged with AFB1 after IBDV vaccine immunization. Furthermore, Lactobacillus salivarius supplementation enhanced Salmonella Pullorum infection resistance in broilers challenged with AFB1. Our results revealed a tremendous potential of Lactobacillus salivarius as feed additive to degrading AFB1 and increasing broilers production performance in poultry production.

Chromium toxicity, speciation, and remediation strategies in soil-plant interface: A critical review.

In recent decades, environmental pollution with chromium (Cr) has gained significant attention. Although chromium (Cr) can exist in a variety of different oxidation states and is a polyvalent element, only trivalent chromium [Cr(III)] and hexavalent chromium [Cr(VI)] are found frequently in the natural environment. In the current review, we summarize the biogeochemical procedures that regulate Cr(VI) mobilization, accumulation, bioavailability, toxicity in soils, and probable risks to ecosystem are also highlighted. Plants growing in Cr(VI)-contaminated soils show reduced growth and development with lower agricultural production and quality. Furthermore, Cr(VI) exposure causes oxidative stress due to the production of free radicals which modifies plant morpho-physiological and biochemical processes at tissue and cellular levels. However, plants may develop extensive cellular and physiological defensive mechanisms in response to Cr(VI) toxicity to ensure their survival. To cope with Cr(VI) toxicity, plants either avoid absorbing Cr(VI) from the soil or turn on the detoxifying mechanism, which involves producing antioxidants (both enzymatic and non-enzymatic) for scavenging of reactive oxygen species (ROS). Moreover, this review also highlights recent knowledge of remediation approaches i.e., bioremediation/phytoremediation, or remediation by using microbes exogenous use of organic amendments (biochar, manure, and compost), and nano-remediation supplements, which significantly remediate Cr(VI)-contaminated soil/water and lessen possible health and environmental challenges. Future research needs and knowledge gaps are also covered. The review's observations should aid in the development of creative and useful methods for limiting Cr(VI) bioavailability, toxicity and sustainably managing Cr(VI)-polluted soils/water, by clear understanding of mechanistic basis of Cr(VI) toxicity, signaling pathways, and tolerance mechanisms; hence reducing its hazards to the environment.

Lessons Learned from Phase II and Phase III Trials Investigating Therapeutic Agents for Cerebral Ischemia Associated with Aneurysmal Subarachnoid Hemorrhage.

One of the challenges in bringing new therapeutic agents (since nimodipine) in for the treatment of cerebral ischemia associated with aneurysmal subarachnoid hemorrhage (aSAH) is the incongruence in therapeutic benefit observed between phase II and subsequent phase III clinical trials. Therefore, identifying areas for improvement in the methodology and interpretation of results is necessary to increase the value of phase II trials. We performed a systematic review of phase II trials that continued into phase III trials, evaluating a therapeutic agent for the treatment of cerebral ischemia associated with aSAH. We followed the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines for systematic reviews, and review was based on a peer-reviewed protocol (International Prospective Register of Systematic Reviews no. 222965). A total of nine phase III trials involving 7,088 patients were performed based on eight phase II trials involving 1558 patients. The following therapeutic agents were evaluated in the selected phase II and phase III trials: intravenous tirilazad, intravenous nicardipine, intravenous clazosentan, intravenous magnesium, oral statins, and intraventricular nimodipine. Shortcomings in several design elements of the phase II aSAH trials were identified that may explain the incongruence between phase II and phase III trial results. We suggest the consideration of the following strategies to improve phase II design: increased focus on the selection of surrogate markers of efficacy, selection of the optimal dose and timing of intervention, adjustment for exaggerated estimate of treatment effect in sample size calculations, use of prespecified go/no-go criteria using futility design, use of multicenter design, enrichment of the study population, use of concurrent control or placebo group, and use of innovative trial designs such as seamless phase II to III design. Modifying the design of phase II trials on the basis of lessons learned from previous phase II and phase III trial combinations is necessary to plan more effective phase III trials.

Curcumin ameliorates duodenal toxicity of AFB1 in chicken through inducing P-glycoprotein and downregulating cytochrome P450 enzymes.

It has been reported that oral intake of aflatoxin B1 (AFB1)-contaminated feed could cause acute, sub-chronic, or chronic toxicity in livestock and poultry. However, the harmful effect of AFB1 on the small intestine is still controversial. Therefore, blocking the entry of AFB1 into the body through the digestive tract is one of the important methods to prevent its toxicity. In the present study, 1-day-old Arbor Acres broilers were randomly divided into 6 groups including control group, curcumin control group (450 mg curcumin/kg feed), curcumin low-, medium-, and high-dose group (150, 300, and 450 mg curcumin/kg feed + 5 mg AFB1/kg feed), and AFB1 group (5 mg AFB1/kg feed). After 28 d, the samples of chickens' duodenums were collected for further analyses. AFB1 caused abnormal functional and morphological changes in the duodenum, including histological lesions, increased the length of the duodenum and depth of crypt, decreased the unit weight of the duodenum, height of villus, and the value of villus height/crypt depth. Meanwhile, AFB1 administration enhanced malonaldehyde activity, 8-HOdG level, and the mRNA expression of cytochrome P450 (CYP450) enzymes, and reduced superoxide dismutase, catalase, adenosine triphosphatase (ATPase) activity and the mRNA expression of Abcb1. Importantly, curcumin supplementation partially ameliorated AFB1-induced abnormal functional and morphological signs of the duodenum, alleviated AFB1-induced oxidative stress, and decreased the mRNA expression of CYP450 enzymes. Furthermore, curcumin ameliorated AFB1-induced decrease in the Abcb1 mRNA expression, P-glycoprotein (P-gp) level, and ATPase activities. It has been suggested from these results that curcumin supplementation in the feed could ameliorate AFB1-induced duodenal toxicity and damage through downregulating CYP450 enzymes, promoting ATPase activities, and inducing P-gp in chickens.

Frequency Of Common Bacteria And Their Antibiotic Sensitivity Pattern In Diabetics Presenting With Foot Ulcer.

BACKGROUND: Foot ulcers are one of the most important complications of diabetes mellitus and often lead to lower limb amputation. Diabetic foot ulcers are susceptible to infection. The objective of this study was to determine the frequency of common bacteria infecting these ulcers and their antibiotic sensitivity pattern. METHODS: This descriptive cross-sectional study was performed in the Departments of Medicine and Surgery, Khyber Teaching Hospital, Peshawar from April, 2011 to February, 2012. Specimens collected from ulcers of 131 patients were inoculated on Blood Agar and MacConkey Agar, and antibiotic sensitivity was tested using standard disc diffusion method. RESULTS: Out of 131, specimens from 120 patients yielded 176 bacteria. Sixty-six patients had monomicrobial infection while polymicrobial growth was obtained in 54 patients. Overall, Staphylococcus aureus (38.6%) was the most common isolate followed by Pseudomonas aeruginosa (27.3%). Staphylococcus aureus was most often sensitive to Moxifloxacin, Imipenem/Meropenem, Vancomycin and Linezolid while it showed varying sensitivity to Penicillins and Cephalosporins. 47.1% isolates of Staphylococcus aureus were resistant to Methicillin. Most of the gram negative rods were sensitive to Imipenem/Meropenem, Piperacillin-Tazobactam and Ticarcillin-Clavulanate. Majority of gram negative bacteria were found resistant to Cephalosporins and Moxifloxacin except Pseudomonas which showed variable sensitivity to Ceftriaxone, Ceftazidime and Moxifloxacin. CONCLUSIONS: Majority of isolates were found resistant to the commonly used antibiotics. Most commonly isolated bacterium, Staphylococcus aureus was most often sensitive to Moxifloxacin, Imipenem/Meropenem, Vancomycin and Linezolid, while majority isolated gram negative rods were sensitive to Imipenem/Meropenem, Piperacillin-Tazobactam and Ticarcillin-Clavulanate.