Phf21b imprints the spatiotemporal epigenetic switch essential for neural stem cell differentiation.

Cerebral cortical development in mammals involves a highly complex and organized set of events including the transition of neural stem and progenitor cells (NSCs) from proliferative to differentiative divisions to generate neurons. Despite progress, the spatiotemporal regulation of this proliferation-differentiation switch during neurogenesis and the upstream epigenetic triggers remain poorly known. Here we report a cortex-specific PHD finger protein, Phf21b, which is highly expressed in the neurogenic phase of cortical development and gets induced as NSCs begin to differentiate. Depletion of Phf21b in vivo inhibited neuronal differentiation as cortical progenitors lacking Phf21b were retained in the proliferative zones and underwent faster cell cycles. Mechanistically, Phf21b targets the regulatory regions of cell cycle promoting genes by virtue of its high affinity for monomethylated H3K4. Subsequently, Phf21b recruits the lysine-specific demethylase Lsd1 and histone deacetylase Hdac2, resulting in the simultaneous removal of monomethylation from H3K4 and acetylation from H3K27, respectively. Intriguingly, mutations in the Phf21b locus associate with depression and mental retardation in humans. Taken together, these findings establish how a precisely timed spatiotemporal expression of Phf21b creates an epigenetic program that triggers neural stem cell differentiation during cortical development.

Biosynthesis of carotenoids in Azospirillum brasilense Cd is mediated via squalene (C30) route.

Azospirillum brasilense is a non-photosynthetic α-Proteobacteria, belongs to the family of Rhodospirillaceae and produces carotenoids to protect itself from photooxidative stress. In this study, we have used Resonance Raman Spectra to show similarity of bacterioruberins of Halobacterium salinarum to that of A. brasilense Cd. To navigate the role of genes involved in carotenoid biosynthesis, we used mutational analysis to inactivate putative genes predicted to be involved in carotenoid biosynthesis in A. brasilense Cd. We have shown that HpnCED enzymes are involved in the biosynthesis of squalene (C30), which is required for the synthesis of carotenoids in A. brasilense Cd. We also found that CrtI and CrtP desaturases were involved in the transformation of colorless squalene into the pink-pigmented carotenoids. This study elucidates role of some genes which constitute very pivotal role in biosynthetic pathway of carotenoid in A. brasilense Cd.

Polyglycerol-Functionalized ß-Cyclodextrins as Crosslinkers in Thermoresponsive Nanogels for the Enhanced Dermal Penetration of Hydrophobic Drugs.

Thermoresponsive nanogels (tNGs) are promising candidates for dermal drug delivery. However, poor incorporation of hydrophobic drugs into hydrophilic tNGs limits the therapeutic efficiency. To address this challenge, ß-cyclodextrins (ß-CD) are functionalized by hyperbranched polyglycerol serving as crosslinkers (hPG-ßCD) to fabricate ßCD-tNGs. This novel construct exhibits augmented encapsulation of hydrophobic drugs, shows the appropriate thermal response to dermal administration, and enhances the dermal penetration of payloads. The structural influences on the encapsulation capacity of ßCD-tNGs for hydrophobic drugs are analyzed, while concurrently retaining their efficacy as skin penetration enhancers. Various synthetic parameters are considered, encompassing the acrylation degree and molecular weight of hPG-ßCD, as well as the monomer composition of ßCD-tNGs. The outcome reveals that ßCD-tNGs substantially enhance the aqueous solubility of Nile Red elevating to 120 µg mL-1 and augmenting its dermal penetration up to 3.33 µg cm-2. Notably, the acrylation degree of hPG-ßCD plays a significant role in dermal drug penetration, primarily attributed to the impact on the rigidity and hydrophilicity of ßCD-tNGs. Taken together, the introduction of the functionalized ß-CD as the crosslinker in tNGs presents a novel avenue to enhance the efficacy of hydrophobic drugs in dermatological applications, thereby offering promising opportunities for boosted therapeutic outcomes.

Nonphototrophic hypocotyl 3 domain proteins: traffic directors, hitchhikers, or both?

The nonphototrophic hypocotyl 3 (NPH3) domain is plant specific and of unknown function. It is nearly always attached to an N-terminal BTB domain and a largely unstructured C-terminal region. Recent reports revealed NPH3-domain GTPase activity and connection to intracellular trafficking, condensate formation, membrane attachment of the C-terminal region for some NPH3-domain proteins and, at the physiological level, drought-related function for at least one NPH3-domain protein. We integrate these new ideas of NPH3-domain protein function into two, nonexclusive, working models: the 'traffic director' model, whereby NPH3-domain proteins regulate intracellular trafficking and, the 'hitchhiker' model whereby NPH3-domain proteins ride the trafficking system to find ubiquitination targets. Determining which model best applies to uncharacterized NPH3-domain proteins will contribute to understanding intracellular trafficking and environmental responses.

Organ dysfunction and failure in liver disease.

Acute-on-chronic liver failure (ACLF) is a complex syndrome defined by the existence of different organ failures (OFs) in patients with chronic liver disease, mainly cirrhosis. Several definitions have been proposed to define the syndrome, varying in the grade of the subjacent liver disease, the type of precipitants and the organs considered in the definition. Liver, coagulation, brain, kidney, circulatory and pulmonary are the six types of OFs proposed in the different classifications, with different prevalence worldwide. Irrespective of the definition used, patients who develop ACLF present a hyperactive immune system, profound haemodynamic disturbances and several metabolic alterations that finally lead to organ dysfunction. These disturbances are triggered by different factors such as bacterial infections, alcoholic hepatitis, gastrointestinal bleeding or hepatitis B virus flare, among others. Because patients with ACLF present high short-term mortality, a prompt recognition is needed to start treatment of the trigger event and specific organ support. Liver transplantation is also feasible in carefully selected patients and should be evaluated.

Improving palliative and supportive care in advanced cirrhosis: the HepatoCare model of integrated collaborative care.

BACKGROUND: Patients with advanced cirrhosis experience an unpredictable disease trajectory but are infrequently referred to palliative care (PC) services and rarely undertake advance care planning (ACP). AIM: We assessed whether a novel model of care increased provision of meaningful PC in advanced cirrhosis compared with standard of care (SOC). METHODS: Thirty consecutive hepatology clinic outpatients with advanced cirrhosis, meeting one or more cirrhosis-related PC referral criteria, consented to treatment in the HepatoCare clinic (PC physician, specialist liver nurse, pharmacist) in parallel with usual specialist hepatology care. A control cohort of 30 consecutive outpatients with advanced cirrhosis undergoing SOC treatment was retrospectively identified for comparison. The primary outcome was provision of meaningful PC using HepatoCare versus SOC. Additional clinical outcomes were assessed over 12 months or until death and significant differences were identified. RESULTS: The intervention and control cohorts had similarly advanced cirrhosis (mean Child-Pugh scores 8.7 vs 8.2, P = 0.46; mean model for end-stage liver disease scores 14.4 vs 14.6, P = 0.88) but a lower 12-month mortality rate (33% HepatoCare vs 67% SOC; P = 0.02). The intervention cohort experienced higher uptake of formal ACP (100% vs 25% for the control cohort) and outpatient PC referral (100% vs 40%), and were more likely to die at home or in a PC bed/hospice (80% vs 30%). The majority of the HepatoCare cohort (81%) had medications safely deprescribed and experienced fewer unplanned admission days (470 vs 794). CONCLUSIONS: HepatoCare is a novel multidisciplinary model of care that integrates effective PC and specialist hepatology management to improve outcomes in advanced cirrhosis.

Insights into microbial diversity on plastisphere by multi-omics.

Plastic pollution is a major concern in marine environment as it takes many years to degrade and is one of the greatest threats to marine life. Plastic surface, referred to as plastisphere, provides habitat for growth and proliferation of various microorganisms. The discovery of these microbes is necessary to identify significant genes, enzymes and bioactive compounds that could help in bioremediation and other commercial applications. Conventional culture techniques have been successful in identifying few microbes from these habitats, leaving majority of them yet to be explored. As such, to recognize the vivid genetic diversity of microbes residing in plastisphere, their structure and corresponding ecological roles within the ecosystem, an emerging technique, called metagenomics has been explored. The technique is expected to provide hitherto unknown information on microbes from the plastisphere. Metagenomics along with next generation sequencing provides comprehensive knowledge on microbes residing in plastisphere that identifies novel microbes for plastic bioremediation, bioactive compounds and other potential benefits. The following review summarizes the efficiency of metagenomics and next generation sequencing technology over conventionally used methods for culturing microbes. It attempts to illustrate the workflow mechanism of metagenomics to elucidate diverse microbial profiles. Further, importance of integrated multi-omics techniques has been highlighted in discovering microbial ecology residing on plastisphere for wider applications.

Selective internal radiation therapy for hepatocellular carcinoma: A 15-year multicenter Australian cohort study.

BACKGROUND AND AIM: The exact place for selective internal radiation therapy (SIRT) in the therapeutic algorithm for hepatocellular carcinoma (HCC) is debated. There are limited data on its indications, efficacy, and safety in Australia. METHODS: We performed a multicenter retrospective cohort study of patients undergoing SIRT for HCC in all Sydney hospitals between 2005 and 2019. The primary outcome was overall survival. Secondary outcomes were progression-free survival and adverse events. RESULTS: During the study period, 156 patients underwent SIRT across 10 institutions (mean age 67 years, 81% male). SIRT use progressively increased from 2005 (n = 2), peaking in 2017 (n = 42) before declining (2019: n = 21). Barcelona Clinic Liver Cancer stages at treatment were A (13%), B (33%), C (52%), and D (2%). Forty-four (28%) patients had tumor thrombus. After a median follow-up of 13.9 months, there were 117 deaths. Median overall survival was 15 months (95% confidence interval 11-19). Independent predictors of mortality on multivariable analysis were extent of liver involvement, Barcelona Clinic Liver Cancer stage, baseline ascites, alpha fetoprotein, and model for end-stage liver disease score. Median progression-free survival was 6.0 months (95% confidence interval 5.1-6.9 months). Following SIRT, 11% of patients were downstaged to curative therapy. SIRT-related complications occurred in 17%: radioembolization-induced liver disease (11%), pneumonitis (3%), gastrointestinal ulceration, and cholecystitis (1% each). Baseline ascites predicted for radioembolization-induced liver disease. CONCLUSION: We present the largest Australian SIRT cohort for HCC. We have identified several factors associated with a poor outcome following SIRT. Patients with early-stage disease had the best survival with some being downstaged to curative therapy.

Effect of Delayed Umbilical Cord Clamping on Hemodynamic Instability in Preterm Neonates below 35 Weeks.

INTRODUCTION: Delaying umbilical cord clamping facilitates postnatal transition in neonates but evidence on its effect in reducing hemodynamic instability in preterm neonates is inconclusive. AIMS: To evaluate delayed cord clamping (DCC) in reducing the incidence of hemodynamic instability in preterm neonates below 35 weeks gestational age admitted to the neonatal intensive care unit. METHODS: Neonates between 25 weeks and 34 weeks and 6 days gestation were enrolled. Hemodynamic and respiratory parameters were monitored over 48 h. Hemodynamic instability was defined as persistent tachycardia and/or hypotension necessitating therapy. RESULTS: The DCC cohort included 62 neonates with an equal number in the non-DCC group. The birth weight [mean ± standard deviation (SD)] was 1332.90 ± 390.05 g and the gestational age (mean ± SD) was 31.64 ± 2.52 weeks. Hemodynamic instability was noted in 18/62 (29%) neonates in the DCC cohort and 29/62 (46.7%) in the non-DCC group; relative risk (RR) 0.62 [95% confidence interval (CI) 0.38-0.99] (p = 0.023). The duration of inotrope requirement in the DCC cohort (mean ± SD) was 38.38 ± 16.99 h compared to 49.13 ± 22.90 h in the non-DCC cohort (p = 0.090). Significantly higher systolic, diastolic and mean arterial pressures were noted from 6 h to 48 h in the DCC cohort (p < 0.001). The severity of respiratory distress and FiO2 requirement was also less in the first 24 h. There was no difference in the incidence of patent ductus arteriosus, late-onset sepsis or mortality. CONCLUSION: Delaying umbilical cord clamping at birth by 60 s resulted in significantly lower hemodynamic instability in the first 48 h and higher blood pressure parameters.

Nanocarriers for Skin Applications: Where Do We Stand?

Skin penetration of active molecules for treatment of diverse diseases is a major field of research owing to the advantages associated with the skin like easy accessibility, reduced systemic-derived side effects, and increased therapeutic efficacy. Despite these advantages, dermal drug delivery is generally challenging due to the low skin permeability of therapeutics. Although various methods have been developed to improve skin penetration and permeation of therapeutics, they are usually aggressive and could lead to irreversible damage to the stratum corneum. Nanosized carrier systems represent an alternative approach for current technologies, with minimal damage to the natural barrier function of skin. In this Review, the use of nanoparticles to deliver drug molecules, genetic material, and vaccines into the skin is discussed. In addition, nanotoxicology studies and the recent clinical development of nanoparticles are highlighted to shed light on their potential to undergo market translation.

Synthetic Tunability and Biophysical Basis for Fabricating Highly Fluorescent and Stable DNA Copper Nanoclusters.

The real motivation in the present work is to tune the synthesis variables that can result in a highly fluorescent and stable DNA copper nanocluster (CuNC) and also to understand the intricate mechanism behind this process. Here, carefully optimized concentrations of various reactants enabled the creation of a DNA-encapsulated CuNC for AT-DNA, displaying a size of <1.0 nm as confirmed by transmission electron microscopy and dynamic light scattering. The extremely small size of the AT-DNACuNC supports the discrete electronic transitions, also characterized by an exceptionally strong negative circular dichroism (CD) band around 350 nm, whose intensity is well correlated with the observed strong fluorescence emission intensity. This remarkably strong CD can open new applications in the detection and quantification of a specific DNACuNC. Further, time-dependent fluorescence analysis suggested stronger photostabilization of these DNACuNCs. The simulation study, based on Cu ion distribution, explained how AT-DNA is a better candidate for NC formation than GC-DNA. In conclusion, the better-tuned synthesis procedure has resulted in a highly compact, well-defined three-dimensional conformation that promotes a more favorable microenvironment to sequester a DNA-based CuNC with high brightness and outstanding photostability.

Synthesis, antimicrobial and chitinase inhibitory activities of 3-amidocoumarins.

A series of 3-amidocoumarins has been synthesized and tested in vitro for their anitimicrobial and chitinase inhibitory activities. Among these, compounds 5k, 5l, 8b-8d, 8f and 8g exhibited good antibacterial activity with MIC values in the range of 6.25-25 µg/mL against some of the tested strains while compounds 5l, 8b, 8c and 8f showed good activity against at least one or two fungal strains. Some of the assayed compounds 5d, 5k, 5l, 8b and 8c displayed significant chitinase inhibitory activity with IC50 values in the range of 3.74-5.6 µM. Among them, 5l proved to be potent chitinase inhibitor with IC50 value of 3.74 µM. To better understand the enzyme-inhibitor interactions molecular docking study of all the synthesized compounds was carried out on Aspergillus fumigatus chitinase 1W9U. The compound 5l showed high binding affinity with the receptor with binding energy value of -8.44 Kcal/mol. This study also provides structure activity relationship (SAR) of synthesized compounds.

JNK-dependent gene regulatory circuitry governs mesenchymal fate.

The epithelial to mesenchymal transition (EMT) is a biological process in which cells lose cell-cell contacts and become motile. EMT is used during development, for example, in triggering neural crest migration, and in cancer metastasis. Despite progress, the dynamics of JNK signaling, its role in genomewide transcriptional reprogramming, and involved downstream effectors during EMT remain largely unknown. Here, we show that JNK is not required for initiation, but progression of phenotypic changes associated with EMT. Such dependency resulted from JNK-driven transcriptional reprogramming of critical EMT genes and involved changes in their chromatin state. Furthermore, we identified eight novel JNK-induced transcription factors that were required for proper EMT. Three of these factors were also highly expressed in invasive cancer cells where they function in gene regulation to maintain mesenchymal identity. These factors were also induced during neuronal development and function in neuronal migration in vivo. These comprehensive findings uncovered a kinetically distinct role for the JNK pathway in defining the transcriptome that underlies mesenchymal identity and revealed novel transcription factors that mediate these responses during development and disease.

Leishmania donovani Parasites Are Inhibited by the Benzoxaborole AN2690 Targeting Leucyl-tRNA Synthetase.

Visceral leishmaniasis is an important public health threat in parts of India. It is caused by a protozoan parasite, Leishmania donovani Currently available drugs manifest severe side effects. Hence, there is a need to identify new drug targets and drugs. Aminoacyl-tRNA synthetases, required for protein synthesis, are known drug targets for bacterial and fungal pathogens. The aim of the present study was to obtain essentiality data for Leishmania donovani leucyl-tRNA synthetase (LdLRS) by gene replacement. Gene replacement studies indicate that this enzyme plays an essential role in the viability of this pathogenic organism and appears to be indispensable for its survival in vitro The heterozygous mutant parasites demonstrated a growth deficit and reduced infectivity in mouse macrophages compared to the wild-type cells. We also report that Leishmania donovani recombinant LRS displayed aminoacylation activity and that the protein localized to both the cytosol and the mitochondrion. A broad-spectrum antifungal, 5-fluoro-1,3-dihydro-1-hydroxy-2,1-benzoxaborole (AN2690), was found to inhibit parasite growth in both the promastigote and amastigote stages in vitro as well as in vivo in BALB/c mice. This compound exhibited low toxicity to mammalian cells. AN2690 was effective in inhibiting the aminoacylation activity of the recombinant LdLRS. We provide preliminary chemical validation of LdLRS as a drug target by showing that AN2690 is an inhibitor both of L. donovani LRS and of L. donovani cell growth.

Biophysical insight into the heparin-peptide interaction and its modulation by a small molecule.

The heparin-protein interaction plays a vital role in numerous physiological and pathological processes. Not only is the binding mechanism of these interactions poorly understood, studies concerning their therapeutic targeting are also limited. Here, we have studied the interaction of the heparin interacting peptide (HIP) from Tat (which plays important role in HIV infections) with heparin. Isothermal titration calorimetry binding exhibits distinct biphasic isotherm with two different affinities in the HIP-heparin complex formation. Overall, the binding was mainly driven by the nonionic interactions with a small contribution from ionic interactions. The stoichiometric analysis suggested that the minimal site for a single HIP molecule is a chain of 4 to 5 saccharide molecules, also supported by docking studies. The investigation was also focused on exploiting the possibility of using a small molecule as an inhibitor of the HIP-heparin complex. Quinacrine, because of its ability to mimic the HIP interactions with heparin, was shown to successfully modulate the HIP-heparin interactions. This result demonstrates the feasibility of inhibiting the disease relevant heparin-protein interactions by a small molecule, which could be an effective strategy for the development of future therapeutic agents.

Molecular insights into trypanothione reductase-inhibitor interaction: A structure-based review.

Information on how small molecules bind to the target enzyme has the potential to impact immensely on how medicinal chemists go about antiparasitic drug discovery. In this review, for the first time, we intend to make an assessment of the structural aspects of trypanothione reductase as drug target, and its complexes with several reversible drugs from the Protein Data Bank (PDB). We attempt to reveal the mechanism of these interactions by careful accounting of the X-ray structures and their possible roles in biological activity to treat Trypanosomatidae diseases. We focus on some of the outstanding findings from structures that are relevant to anti-trypanocidal drug discovery. We also review new interesting compounds that have appeared in the literature based on these X-ray structures.

TOX3 regulates neural progenitor identity.

The human genomic locus for the transcription factor TOX3 has been implicated in susceptibility to restless legs syndrome and breast cancer in genome-wide association studies, but the physiological role of TOX3 remains largely unknown. We found Tox3 to be predominantly expressed in the developing mouse brain with a peak at embryonic day E14 where it co-localizes with the neural stem and progenitor markers Nestin and Sox2 in radial glia of the ventricular zone and intermediate progenitors of the subventricular zone. Tox3 is also expressed in neural progenitor cells obtained from the ganglionic eminence of E15 mice that express Nestin, and it specifically binds the Nestin promoter in chromatin immunoprecipitation assays. In line with this, over-expression of Tox3 increased Nestin promoter activity, which was cooperatively enhanced by treatment with the stem cell self-renewal promoting Notch ligand Jagged and repressed by pharmacological inhibition of Notch signaling. Knockdown of Tox3 in the subventricular zone of E12.5 mouse embryos by in utero electroporation of Tox3 shRNA revealed a reduced Nestin expression and decreased proliferation at E14 and a reduced migration to the cortical plate in E16 embryos in electroporated cells. Together, these results argue for a role of Tox3 in the development of the nervous system.

Mechanoluminescence Study of Europium Doped CaZrO3 Phosphor.

Behaviour displayed by mechanoluminescence (ML) in CaZrO3:Eu(3+) doped phosphors with variable concentration of europium ions are described. When the ML is excited impulsively by the impact of a load on the phosphors the ML intensity increases with time, attains a maximum value and then it decreases. In the ML intensity versus time curve, the peak increases and shifts towards shorter time values with increasing impact velocities. Sample was synthesized by combustion synthesis method with variable concentration of Eu(3+) ions (0.1, 0.2, 0.5, 1, 1.5 mol%) and characterized by X-ray diffraction technique. The total ML intensity IT is defined as the area below the ML intensity versus time curve. Initially IT increases with impact velocity V0 of the load and then it attains a saturation value for higher values of impact velocities which follow the relation IT = IT (0) exp.(-Vc/V0) where IT (0) and Vc are constants. Total ML intensity increases linearly with the mass of the phosphors for higher impact velocities. The ML intensity Im, corresponding to the peak of ML intensity versus time curve increases linearly with the impact velocities. The time tm, is found to be linearly related to 1000/V0. The mechanoluminescence induced by impulsive excitation in europium doped CaZrO3 phosphors plays a significance role in the understanding of biological sensors and display device application.

Luminescence studies and infrared emission of erbium-doped calcium zirconate phosphor.

The near-infrared-to-visible upconversion luminescence behaviour of Er(3+)-doped CaZrO3 phosphor is discussed in this manuscript. The phosphor was prepared by a combustion synthesis technique that is suitable for less-time-taking techniques for nanophosphors. The starting materials used for sample preparation were Ca(NO3)2.4H2O, Zr(NO3)4 and Er(NO3)2, and urea was used as a fuel. The prepared sample was characterized by X-ray diffraction (XRD). The surface morphology of prepared phosphor was determined by field emission gun scanning electron microscopy (FEGSEM). The functional group analysis was determined by Fourier transform infrared (FTIR) spectroscopy. All prepared phosphors with variable Er(3+) concentrations (0.5-2.5 mol%) were studied by photoluminescence analysis. It was found that the excitation spectra of the prepared phosphor showed a sharp excitation peak centred at 980 nm. The emission spectra with variable Er(3+) concentrations showed strong peaks in the 555 nm and 567 nm range, with a dominant peak at 555 nm due to the ((2)H(11/2),(4)S(3/2)) transition and a weaker transition at 567 nm associated with 527 nm. Spectrophotometric determination of the peak was evaluated by the Commission Internationale de I'Eclairage (CIE) method These upconverted emissions were attributed to a two-photon process. The excitation wavelength dependence of the upconverted luminescence, together with its time evolution after infrared pulsed excitation, suggested that energy transfer upconversion processes were responsible for the upconversion luminescence. The upconversion mechanisms were studied in detail through laser power dependence. Excited state absorption and energy transfer processes were discussed as possible upconversion mechanisms. The cross-relaxation process in Er(3+) was also investigated.

Transcription factor Dlx2 protects from TGFß-induced cell-cycle arrest and apoptosis.

Acquiring resistance against transforming growth factor ß (TGFß)-induced growth inhibition at early stages of carcinogenesis and shifting to TGFß's tumour-promoting functions at later stages is a pre-requisite for malignant tumour progression and metastasis. We have identified the transcription factor distal-less homeobox 2 (Dlx2) to exert critical functions during this switch. Dlx2 counteracts TGFß-induced cell-cycle arrest and apoptosis in mammary epithelial cells by at least two molecular mechanisms: Dlx2 acts as a direct transcriptional repressor of TGFß receptor II (TGFßRII) gene expression and reduces canonical, Smad-dependent TGFß signalling and expression of the cell-cycle inhibitor p21(CIP1) and increases expression of the mitogenic transcription factor c-Myc. On the other hand, Dlx2 directly induces the expression of the epidermal growth factor (EGF) family member betacellulin, which promotes cell survival by stimulating EGF receptor signalling. Finally, Dlx2 expression supports experimental tumour growth and metastasis of B16 melanoma cells and correlates with tumour malignancy in a variety of human cancer types. These results establish Dlx2 as one critical player in shifting TGFß from its tumour suppressive to its tumour-promoting functions.