High-rate algal ponds (HRAPs) incorporate shallow raceway designs and paddlewheel mixing. HRAPs use UV disinfection and the symbiotic environment between microalgal photosynthesis and heterotrophic ...bacteria for the assimilation of nutrients for efficient wastewater treatment. Mixing of a HRAP provides a homogenous environment and influences both the disinfection of pathogens and algal growth by exposing the wastewater to sunlight. Guidelines require continuous mixing of the HRAP. This study aimed to determine the effect of cessation of mixing for 10 days, on wastewater treatment by comparison with a continuously mixed pond operated over the same period. The period of 10 days was equivalent to the HRAP hydraulic retention time. Samples of inlet and HRAP-treated wastewater were collected from the HRAP at Kingston on Murray. Parameters measured were Escherichia coli, chlorophyll a, total suspended solids (TSS), NH
-N, NO
-N, NO
-N, PO
-P and biochemical oxygen demand (BOD
). The discontinuously mixed and the continuously mixed HRAPs complied with the wastewater effluent guidelines, of an E. coli concentration ≤104 MPN100 mL
and a BOD
of <20 mg L
. An E. coli log reduction value of >1 was also recorded. This study shows that cessation of mixing for 10 days had no significant effect on HRAP wastewater treatment performance.
Although nanomedicine has been highly investigated for cancer treatment over the past decades, only a few nanomedicines are currently approved and in the market; making this field poorly represented ...in clinical applications. Key research gaps that require optimization to successfully translate the use of nanomedicines have been identified, but not addressed; among these, the lack of control of the release pattern of therapeutics is the most important. To solve these issues with currently used nanomedicines (e.g., burst release, systemic release), different strategies for the design and manufacturing of nanomedicines allowing for better control over the therapeutic release, are currently being investigated. The inclusion of stimuli-responsive properties and prolonged drug release have been identified as effective approaches to include in nanomedicine, and are discussed in this paper. Recently, smart sustained release nanoparticles have been successfully designed to safely and efficiently deliver therapeutics with different kinetic profiles, making them promising for many drug delivery applications and in specific for cancer treatment. In this review, the state-of-the-art of smart sustained release nanoparticles is discussed, focusing on the design strategies and performances of polymeric nanotechnologies. A complete list of nanomedicines currently tested in clinical trials and approved nanomedicines for cancer treatment is presented, critically discussing advantages and limitations with respect to the newly developed nanotechnologies and manufacturing methods. By the presented discussion and the highlight of nanomedicine design criteria and current limitations, this review paper could be of high interest to identify key features for the design of release-controlled nanomedicine for cancer treatment.
The circadian clock regulates immune responses to microbes and affects pathogen replication, but the underlying molecular mechanisms are not well understood. Here we demonstrate that the circadian ...components BMAL1 and REV-ERBα influence several steps in the hepatitis C virus (HCV) life cycle, including particle entry into hepatocytes and RNA genome replication. Genetic knock out of Bmal1 and over-expression or activation of REV-ERB with synthetic agonists inhibits the replication of HCV and the related flaviruses dengue and Zika via perturbation of lipid signaling pathways. This study highlights a role for the circadian clock component REV-ERBα in regulating flavivirus replication.
Rapid, accurate prediction of protein structure from amino acid sequence would accelerate fields as diverse as drug discovery, synthetic biology and disease diagnosis. Massively improved prediction ...of protein structures has been driven by improving the prediction of the amino acid residues that contact in their 3D structure. For an average globular protein, around 92% of all residue pairs are non-contacting, therefore accurate prediction of only a small percentage of inter-amino acid distances could increase the number of constraints to guide structure determination. We have trained deep neural networks to predict inter-residue contacts and distances. Distances are predicted with an accuracy better than most contact prediction techniques. Addition of distance constraints improved de novo structure predictions for test sets of 158 protein structures, as compared to using the best contact prediction methods alone. Importantly, usage of distance predictions allows the selection of better models from the structure pool without a need for an external model assessment tool. The results also indicate how the accuracy of distance prediction methods might be improved further.
A novel series of small-molecule inhibitors has been developed to target the double mutant form of the epidermal growth factor receptor (EGFR) tyrosine kinase, which is resistant to treatment with ...gefitinib and erlotinib. Our reported compounds also show selectivity over wild-type EGFR. Guided by molecular modeling, this series was evolved to target a cysteine residue in the ATP binding site via covalent bond formation and demonstrates high levels of activity in cellular models of the double mutant form of EGFR. In addition, these compounds show significant activity against the activating mutations, which gefitinib and erlotinib target and inhibition of which gives rise to their observed clinical efficacy. A glutathione (GSH)-based assay was used to measure thiol reactivity toward the electrophilic functionality of the inhibitor series, enabling both the identification of a suitable reactivity window for their potency and the development of a reactivity quantitative structure-property relationship (QSPR) to support design.
Obesity increases the risk of hip osteoarthritis (OA). Recent studies have shown that adipokine extracellular nicotinamide phosphoribosyltransferase (eNAMPT or visfatin) induces the production of ...IL-6 and matrix metalloproteases (MMPs) in chondrocytes, suggesting it may promote articular cartilage degradation. However, neither the functional effects of extracellular visfatin on human articular cartilage tissue, nor its expression in the joint of hip OA patients of varying BMI, have been reported. Hip OA joint tissues were collected from patients undergoing joint replacement surgery. Cartilage explants were stimulated with recombinant human visfatin. Pro-inflammatory cytokines and MMPs were measured by ELISA and Luminex. Localisation of visfatin expression in cartilage tissue was determined by immunohistochemistry. Cartilage matrix degradation was determined by quantifying proteoglycan release. Expression of visfatin was elevated in the synovial tissue of hip OA patients who were obese, and was co-localised with MMP-13 in areas of cartilage damage. Visfatin promoted the degradation of hip OA cartilage proteoglycan and induced the production of pro-inflammatory cytokines (IL-6, MCP-1, CCL20, and CCL4) and MMPs. The elevated expression of visfatin in the obese hip OA joint, and its functional effects on hip cartilage tissue, suggests it plays a central role in the loss of cartilage integrity in obese patients with hip OA.
Chronic hepatitis B virus (HBV) infection is a major cause of liver disease and cancer worldwide for which there are no curative therapies. The major challenge in curing infection is eradicating or ...silencing the covalent closed circular DNA (cccDNA) form of the viral genome. The circadian factors BMAL1/CLOCK and REV-ERB are master regulators of the liver transcriptome and yet their role in HBV replication is unknown. We establish a circadian cycling liver cell-model and demonstrate that REV-ERB directly regulates NTCP-dependent hepatitis B and delta virus particle entry. Importantly, we show that pharmacological activation of REV-ERB inhibits HBV infection in vitro and in human liver chimeric mice. We uncover a role for BMAL1 to bind HBV genomes and increase viral promoter activity. Pharmacological inhibition of BMAL1 through REV-ERB ligands reduces pre-genomic RNA and de novo particle secretion. The presence of conserved E-box motifs among members of the Hepadnaviridae family highlight an evolutionarily conserved role for BMAL1 in regulating this family of small DNA viruses.
The cofactor nicotinamide adenine dinucleotide (NAD+) plays a key role in a wide range of physiological processes and maintaining or enhancing NAD+ levels is an established approach to enhancing ...healthy aging. Recently, several classes of nicotinamide phosphoribosyl transferase (NAMPT) activators have been shown to increase NAD+ levels in vitro and in vivo and to demonstrate beneficial effects in animal models. The best validated of these compounds are structurally related to known urea-type NAMPT inhibitors, however the basis for the switch from inhibitory activity to activation is not well understood. Here we report an evaluation of the structure activity relationships of NAMPT activators by designing, synthesising and testing compounds from other NAMPT ligand chemotypes and mimetics of putative phosphoribosylated adducts of known activators. The results of these studies led us to hypothesise that these activators act via a through-water interaction in the NAMPT active site, resulting in the design of the first known urea-class NAMPT activator that does not utilise a pyridine-like warhead, which shows similar or greater activity as a NAMPT activator in biochemical and cellular assays relative to known analogues.
Chemistry-led investigation of the structure activity relationships of urea-class NAMPT activators resulting in the discovery of non-pyridyl class compounds with enhanced cellular and phenotypic activity. Display omitted
Background Prolonged activation of angiotensin II is the main mediator that contributes to the development of heart diseases, so converting angiotensin II into angiotensin 1-7 has emerged as a new ...strategy to attenuate detrimental effects of angiotensin II. Prolylcarboxypeptidase is a lysosomal pro-X carboxypeptidase that is able to cleave angiotensin II at a preferential acidic pH optimum. However, insufficient attention has been given to the cardioprotective functions of prolylcarboxylpeptidase. Methods and Results We established a CRISPR/CRISPR-associated protein 9-mediated global prolylcarboxylpeptidase-knockout and adeno-associated virus serotype 9-mediated cardiac prolylcarboxylpeptidase overexpression mouse models, which were challenged with the angiotensin II infusion (2 mg/kg per day) for 4 weeks, aiming to investigate the cardioprotective effect of prolylcarboxylpeptidase against hypertensive cardiac hypertrophy. Prolylcarboxylpeptidase expression was upregulated after 2 weeks of angiotensin II infusion and then became downregulated afterward in wild-type mouse myocardium, suggesting its compensatory function against angiotensin II stress. Moreover, angiotensin II-treated prolylcarboxylpeptidase-knockout mice showed aggravated cardiac remodeling and dampened cardiac contractility independent of hypertension. We also found that prolylcarboxylpeptidase localizes in cardiomyocyte lysosomes, and loss of prolylcarboxylpeptidase led to excessive angiotensin II levels in myocardial tissue. Further screening demonstrated that hypertrophic prolylcarboxylpeptidase-knockout hearts showed upregulated extracellular signal-regulated kinases 1/2 and downregulated protein kinase B activities. Importantly, adeno-associated virus serotype 9-mediated restoration of prolylcarboxylpeptidase expression in prolylcarboxylpeptidase-knockout hearts alleviated angiotensin II-induced hypertrophy, fibrosis, and cell death. Interestingly, the combination of adeno-associated virus serotype 9-mediated prolylcarboxylpeptidase overexpression and an antihypertensive drug, losartan, likely conferred more effective protection than a single treatment protocol to mitigate angiotensin II-induced cardiac dysfunction. Conclusions Our data demonstrate that prolylcarboxylpeptidase protects the heart from angiotensin II-induced hypertrophic remodeling by controlling myocardial angiotensin II levels.
High yields and high levels of stereocontrol are observed in the oxidative cyclization of vicinal diols using catalytic amounts of a transition metal (see scheme; TFA=trifluoroacetic acid). The ...product stereochemistry is controlled completely by the starting material, and, importantly, single enantiomers can be accessed readily. The reaction sequence is demonstrated in a very short formal synthesis of the natural product (+)‐cis‐solamin.
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