A kinetic dichotomy between mitochondrial and nuclear gene expression processes.

Oxidative phosphorylation (OXPHOS) complexes, encoded by both mitochondrial and nuclear DNA, are essential producers of cellular ATP, but how nuclear and mitochondrial gene expression steps are coordinated to achieve balanced OXPHOS subunit biogenesis remains unresolved. Here, we present a parallel quantitative analysis of the human nuclear and mitochondrial messenger RNA (mt-mRNA) life cycles, including transcript production, processing, ribosome association, and degradation. The kinetic rates of nearly every stage of gene expression differed starkly across compartments. Compared with nuclear mRNAs, mt-mRNAs were produced 1,100-fold more, degraded 7-fold faster, and accumulated to 160-fold higher levels. Quantitative modeling and depletion of mitochondrial factors LRPPRC and FASTKD5 identified critical points of mitochondrial regulatory control, revealing that the mitonuclear expression disparities intrinsically arise from the highly polycistronic nature of human mitochondrial pre-mRNA. We propose that resolving these differences requires a 100-fold slower mitochondrial translation rate, illuminating the mitoribosome as a nexus of mitonuclear co-regulation.

Plasmon-induced efficient hot carrier generation in graphene on gold ultrathin film with periodic array of holes: Ultrafast pump-probe spectroscopy.

Using ultrafast pump-probe reflectivity with a 3.1 eV pump and coherent white light probe (1.1-2.6 eV), we show that graphene on gold nanostructures exhibits a strong coupling to the plasmonic resonances of the ordered lattice hole array, thus injecting a high density of hot carriers in graphene through plasmons. The system being studied is single-layer graphene on an ultrathin film of gold with periodic arrangements of holes showing anomalous transmission. A comparison is made with gold film with and without hole array. By selectively probing transient carrier dynamics in the spectral regions corresponding to plasmonic resonances, we show efficient plasmon induced hot carrier generation in graphene. We also show that due to high electromagnetic field intensities at the edge of the submicron holes, fast decay time (10-100 fs), and short decay length (1 nm) of plasmons, a highly confined density of hot carriers (very close to the edge of the holes) is generated by Landau damping of plasmons within the holey gold film. A contribution to transient decay dynamics due to the diffusion of the initial nonuniform distribution of hot carriers away from the hole edges is observed. Our results are important for future applications of novel hot carrier device concepts where hot carriers with tunable energy can be generated in different graphene regions connected seamlessly.

Steering healthcare service delivery: a regulatory perspective.

PURPOSE: The purpose of this paper is to explore regulation in India's healthcare sector and makes recommendations needed for enhancing the healthcare service. DESIGN/METHODOLOGY/APPROACH: The literature was reviewed to understand healthcare's regulatory context. To understand the current healthcare system, qualitative data were collected from state-level officials, public and private hospital staff. A patient survey was performed to assess service quality (QoS). FINDINGS: Regulation plays a central role in driving healthcare QoS. India needs to strengthen market and institutional co-production based approaches for steering its healthcare in which delivery processes are complex and pose different challenges. RESEARCH LIMITATIONS/IMPLICATIONS: This study assesses current healthcare regulation in an Indian state and presents a framework for studying and strengthening regulation. Agile regulation should be based on service delivery issues (pull approach) rather than monitoring and sanctions based regulatory environment (push approach). PRACTICAL IMPLICATIONS: Healthcare pitfalls across the world seem to follow similar follies. India's complexity and experience is useful for emerging and developed economies. ORIGINALITY/VALUE: The author reviewed around 70 publications and synthesised them in healthcare regulatory contexts. Patient's perception of private providers could be a key input towards steering regulation. Identifying gaps across QoS dimensions would be useful in taking corrective measures.

Does the purchase intention of green consumers align with their zero-waste buying behaviour? An empirical study on a proactive approach towards embracing waste-free consumption.

In recent years, emerging retail markets in cosmetics have transformed into green markets, as consumers demand more eco-friendly products. However, in scholarly literature, limited studies are available where researchers discuss green consumers' purchase intentions towards eco-friendly products and their relationship with zero-waste buying behaviour. This study is conducted to address the existing gap in current literature. An empirical investigation is carried out, focusing on individuals who use cosmetic products and are active followers of zero-waste beauty influencers on social media. Responses are gathered for data analysis with the help of partial least squares structural equation modelling (PLS-SEM). The results indicate that eco-friendly packaging, pro-environmental belief, and para-social interaction positively impact the altruistic motivation and purchase intention of consumers. Ultimately, these factors collectively contribute to the purchase of zero-waste cosmetic products. The findings of this study can provide valuable insights for policymakers and brand managers in the field of herbal cosmetic formulations. These insights can help in understanding the fundamental reasons that drive consumers to buy zero-waste cosmetic items, potentially leading to a decrease in ecological impact. Additionally, the study contributes to the theory of planned behaviour (TPB) by investigating consumers' purchase intention towards eco-friendly products and their zero-waste buying behaviour.

Efficacy of nicorandil and ranolazine in prevention of contrast-induced nephropathy in patients with mild-to-moderate renal dysfunction: a randomized controlled trial.

INTRODUCTION: Contrast-induced nephropathy (CIN) is a common complication after percutaneous coronary intervention (PCI). There is conflicting evidence regarding efficacy of nicorandil in CIN prevention. With respect to ranolazine, there is physiological possibility as well as data in animal study regarding its protective effect against CIN; there is, however, no human data till date. AIM AND OBJECTIVES: To assess the efficacy of nicorandil and ranolazine in preventing CIN. The secondary endpoint was to measure difference in postprocedure acute kidney injury (AKI) incidence across groups. Also, patients were followed up till 6 months for major adverse events. MATERIAL AND METHODS: This single-center randomized controlled study included 315 patients of coronary artery disease with mild-to-moderate renal dysfunction undergoing elective PCI. Eligible patients were assigned to either nicorandil (n = 105), ranolazine (n = 105) or control group (n = 105) in 1 : 1 : 1 ratio by block randomization. All enrolled patients were given intravenous sodium chloride at rate of 1.0 mL/kg/h (0.5 mL/kg/h for patients with left ventricular ejection fraction <45%) from 6 h before procedure till 12 h after procedure. Iso-osmolar contrast agent (iodixanol) was used for all patients. In addition to hydration, patients in nicorandil group received oral nicorandil (10 mg, 3 times/d) and those in ranolazine group received oral ranolazine (1000 mg, 2 times/d) 1 day before procedure and for 2 days after PCI. Patients in control group received only hydration. RESULTS: Total number of CIN was 34 (10.7%), which included 19 (18.1%) in control, 8 (7.6%) in nicorandil and 7 (6.6%) in ranolazine group. There was significant association of CIN reduction across groups ( P  = 0.012). On pairwise comparison also, there was significant benefit across control and ranolazine as well as control and nicorandil ( P  < 0.025). There was numerically higher incidence of AKI in controls; the difference, however, did not reach statistical significance after applying Bonferroni correction ( P  = 0.044). Over 6-month follow-up, adverse events were similar across groups. CONCLUSION: While this study adds to existing literature that supports role for nicorandil in CIN prevention, the efficacy of ranolazine in protecting against CIN has been demonstrated in humans for the first time.

A Comparative Retrospective Survival Analysis Study of Brain Tumor Patients in Age Less Than or Equal to 50 Years versus More Than 50 Years of Age.

Introduction Approximately 2.5% of fatalities from cancer are caused by brain tumors. Even though there is literature regarding prognostic factor of adult brain tumor, studies often resort to Western demographics. Hence, we conducted this retrospective observational study to compare the demographic characteristics and prognosis in patients of glial tumors in Indian population with histological diagnosis with respect to age. Materials and Methods A single-center retrospective observational study with 76 patients of glioma who had been treated with surgery combined with radiotherapy with or without chemotherapy was conducted. Group I patients were aged less than or equal to 50 years and group II more than 50 years of age. There were 28 patients in group I and 48 in group II. Postoperatively, external beam radiation therapy was delivered in a conventional fraction (1.8 Gy/fraction, five fractions/week) using telecobalt 60. Ill patients who presented with grade III and IV gliomas received oral chemotherapy temozolomide at a dose of 100 mg daily during course of radiotherapy. Results The median age of the patients at the time of diagnosis was 45.0 years. More cases of hematologic toxicity occurred in group I than in group II. Total 55 patients were alive at 1-year follow-up (11 in group I and 44 in group II). Conclusion Grade I and II gliomas were predominant in less than 50 years of age and grade III and IV were predominant in more than 50 years age. Male preponderance was seen in age group of more than 50 years (68%). Overall survival and disease-free survival were better for patients aged less than 50 years.

Comparison of Root Coverage by the Subepithelial Connective Tissue Graft With and Without Root Biomodification: A Comprehensive Clinical Study.

BACKGROUND: Being an autologous graft, a subepithelial connective tissue (SECT) graft shows more predictable root coverage better than other techniques. Hence, it is most likely to be widely used for recession treatment. During root planing, a smear layer forms on the root surface that cannot be removed by water or saline rinsing. To remove this smear layer, root biomodification agents are widely used. The present study was conducted to assess the efficacy of an SECT graft for root coverage with and without root biomodification. METHODS: This study included 20 patients with no gender predilection, with an age range of 24-36 years and a mean age of 27.6 ± 4.24 years. The chosen range facilitated the acquisition of data in a relatively homogeneous population, minimizing the confounding effects of factors such as aging-related tissue changes or early-onset periodontal issues. All 40 sites were treated with the SECT and coronally advanced flap. Root conditioning in controls was done with distilled saline and tested using 24% ethylenediaminetetraacetic acid (EDTA) gel (Maquira; STM Meditech, Kerala). At baseline and at one, three, and six months postoperatively, pocket depth (PD) and clinical attachment levels (CALs) were assessed at four sites using a UNC-15 probe, and from the gingival margin to the cementoenamel junction (CEJ), the vertical recession was assessed. RESULTS: For the buccal surface, CALs were reduced significantly (p < 0.001). Following root conditioning with 24% EDTA, no difference was seen in the CAL in the control and test group either buccally or interproximally with a p-value of greater than 0.05. For PD, following a SECT graft or root conditioning, no significant change was observed in the buccal or interproximal region (p > 0.05). The vertical recession was significantly reduced with a p-value of less than 0.001 and depth coverage of 97.5%. The difference between the two groups was statistically non-significant (p > 0.05). The root surface coverage decreased significantly from 16.6 ± 2.8 to 0.45 ± 0.4 from baseline to six months, which was statistically significant (p < 0.001). This intergroup difference was non-statistical (p > 0.05). CONCLUSION: The present study concludes that the use of an SECT graft in root coverage can significantly improve the CAL, root surface area, and vertical recession both with and without root biomodification. We conclude that there is a significant decrease in the probing depth following SECT grafting and with root biomodification.

Regulators of mitonuclear balance link mitochondrial metabolism to mtDNA expression.

Mitochondrial oxidative phosphorylation (OXPHOS) complexes are assembled from proteins encoded by both nuclear and mitochondrial DNA. These dual-origin enzymes pose a complex gene regulatory challenge for cells requiring coordinated gene expression across organelles. To identify genes involved in dual-origin protein complex synthesis, we performed fluorescence-activated cell-sorting-based genome-wide screens analysing mutant cells with unbalanced levels of mitochondrial- and nuclear-encoded subunits of Complex IV. We identified genes involved in OXPHOS biogenesis, including two uncharacterized genes: PREPL and NME6. We found that PREPL specifically impacts Complex IV biogenesis by acting at the intersection of mitochondrial lipid metabolism and protein synthesis, whereas NME6, an uncharacterized nucleoside diphosphate kinase, controls OXPHOS biogenesis through multiple mechanisms reliant on its NDPK domain. Firstly, NME6 forms a complex with RCC1L, which together perform nucleoside diphosphate kinase activity to maintain local mitochondrial pyrimidine triphosphate levels essential for mitochondrial RNA abundance. Secondly, NME6 modulates the activity of mitoribosome regulatory complexes, altering mitoribosome assembly and mitochondrial RNA pseudouridylation. Taken together, we propose that NME6 acts as a link between compartmentalized mitochondrial metabolites and mitochondrial gene expression.

Genome-wide screens for mitonuclear co-regulators uncover links between compartmentalized metabolism and mitochondrial gene expression.

Mitochondrial oxidative phosphorylation (OXPHOS) complexes are assembled from proteins encoded by both nuclear and mitochondrial DNA. These dual-origin enzymes pose a complex gene regulatory challenge for cells, in which gene expression must be coordinated across organelles using distinct pools of ribosomes. How cells produce and maintain the accurate subunit stoichiometries for these OXPHOS complexes remains largely unknown. To identify genes involved in dual-origin protein complex synthesis, we performed FACS-based genome-wide screens analyzing mutant cells with unbalanced levels of mitochondrial- and nuclear-encoded subunits of cytochrome c oxidase (Complex IV). We identified novel genes involved in OXPHOS biogenesis, including two uncharacterized genes: PREPL and NME6 . We found that PREPL specifically regulates Complex IV biogenesis by interacting with mitochondrial protein synthesis machinery, while NME6, an uncharacterized nucleoside diphosphate kinase (NDPK), controls OXPHOS complex biogenesis through multiple mechanisms reliant on its NDPK domain. First, NME6 maintains local mitochondrial pyrimidine triphosphate levels essential for mitochondrial RNA abundance. Second, through stabilizing interactions with RCC1L, NME6 modulates the activity of mitoribosome regulatory complexes, leading to disruptions in mitoribosome assembly and mitochondrial RNA pseudouridylation. Taken together, we propose that NME6 acts as a link between compartmentalized mitochondrial metabolites and mitochondrial gene expression. Finally, we present these screens as a resource, providing a catalog of genes involved in mitonuclear gene regulation and OXPHOS biogenesis.

A kinetic dichotomy between mitochondrial and nuclear gene expression drives OXPHOS biogenesis.

Oxidative phosphorylation (OXPHOS) complexes, encoded by both mitochondrial and nuclear DNA, are essential producers of cellular ATP, but how nuclear and mitochondrial gene expression steps are coordinated to achieve balanced OXPHOS biogenesis remains unresolved. Here, we present a parallel quantitative analysis of the human nuclear and mitochondrial messenger RNA (mt-mRNA) life cycles, including transcript production, processing, ribosome association, and degradation. The kinetic rates of nearly every stage of gene expression differed starkly across compartments. Compared to nuclear mRNAs, mt-mRNAs were produced 700-fold higher, degraded 5-fold faster, and accumulated to 170-fold higher levels. Quantitative modeling and depletion of mitochondrial factors, LRPPRC and FASTKD5, identified critical points of mitochondrial regulatory control, revealing that the mitonuclear expression disparities intrinsically arise from the highly polycistronic nature of human mitochondrial pre-mRNA. We propose that resolving these differences requires a 100-fold slower mitochondrial translation rate, illuminating the mitoribosome as a nexus of mitonuclear co-regulation.

mTOR Pathway Somatic Pathogenic Variants in Focal Malformations of Cortical Development: Novel Variants, Topographic Mapping, and Clinical Outcomes.

Background and Objectives: Somatic and germline pathogenic variants in genes of the mammalian target of rapamycin (mTOR) signaling pathway are a common mechanism underlying a subset of focal malformations of cortical development (FMCDs) referred to as mTORopathies, which include focal cortical dysplasia (FCD) type II, subtypes of polymicrogyria, and hemimegalencephaly. Our objective is to screen resected FMCD specimens with mTORopathy features on histology for causal somatic variants in mTOR pathway genes, describe novel pathogenic variants, and examine the variant distribution in relation to neuroimaging, histopathologic classification, and clinical outcomes. Methods: We performed ultra-deep sequencing using a custom HaloPlexHS Target Enrichment kit in DNA from 21 resected fresh-frozen histologically confirmed FCD type II, tuberous sclerosis complex, or hemimegalencephaly specimens. We mapped the variant alternative allele frequency (AAF) across the resected brain using targeted ultra-deep sequencing in multiple formalin-fixed paraffin-embedded tissue blocks. We also functionally validated 2 candidate somatic MTOR variants and performed targeted RNA sequencing to validate a splicing defect associated with a novel DEPDC5 variant. Results: We identified causal mTOR pathway gene variants in 66.7% (14/21) of patients, of which 13 were somatic with AAF ranging between 0.6% and 12.0%. Moreover, the AAF did not predict balloon cell presence. Favorable seizure outcomes were associated with genetically clear resection borders. Individuals in whom a causal somatic variant was undetected had excellent postsurgical outcomes. In addition, we demonstrate pathogenicity of the novel c.4373_4375dupATG and candidate c.7499T>A MTOR variants in vitro. We also identified a novel germline aberrant splice site variant in DEPDC5 (c.2802-1G>C). Discussion: The AAF of somatic pathogenic variants correlated with the topographic distribution, histopathology, and postsurgical outcomes. Moreover, cortical regions with absent histologic FCD features had negligible or undetectable pathogenic variant loads. By contrast, specimens with frank histologic abnormalities had detectable pathogenic variant loads, which raises important questions as to whether there is a tolerable variant threshold and whether surgical margins should be clean, as performed in tumor resections. In addition, we describe 2 novel pathogenic variants, expanding the mTORopathy genetic spectrum. Although most pathogenic somatic variants are located at mutation hotspots, screening the full-coding gene sequence remains necessary in a subset of patients.

Microfluidic fabrication of lipid nanoparticles for the delivery of nucleic acids.

Gene therapy has emerged as a potential platform for treating several dreaded and rare diseases that would not have been possible with traditional therapies. Viral vectors have been widely explored as a key platform for gene therapy due to their ability to efficiently transport nucleic acid-based therapeutics into the cells. However, the lack of precision in their delivery has led to several off-target toxicities. As such, various strategies in the form of non-viral gene delivery vehicles have been explored and are currenlty employed in several therapies including the SARS-CoV-2 vaccine. In this review, we discuss the opportunities lipid nanoparticles (LNPs) present for efficient gene delivery. We also discuss various synthesis strategies via microfluidics for high throughput fabrication of non-viral gene delivery vehicles. We conclude with the recent applications and clinical trials of these vehicles for the delivery of different genetic materials such as CRISPR editors and RNA for different medical conditions ranging from cancer to rare diseases.

Charge storage in mesoscopic graphitic islands fabricated using AFM bias lithography.

Electrochemical oxidation and etching of highly oriented pyrolytic graphite (HOPG) has been achieved using biased atomic force microscopy (AFM) lithography, allowing patterns of varying complexity to be written into the top layers of HOPG. The graphitic oxidation process and the trench geometry after writing were monitored using intermittent contact mode AFM. Electrostatic force microscopy reveals that the isolated mesoscopic islands formed during the AFM lithography process become positively charged, suggesting that they are laterally isolated from the surrounding HOPG substrate. The electrical transport studies of these laterally isolated finite-layer graphitic islands enable detailed characterization of electrical conduction along the c-direction and reveal an unexpected stability of the charged state. Utilizing conducting-atomic force microscopy, the measured I(V) characteristics revealed significant non-linearities. Micro-Raman studies confirm the presence of oxy functional groups formed during the lithography process.

MCART1/SLC25A51 is required for mitochondrial NAD transport.

The nicotinamide adenine dinucleotide (NAD+/NADH) pair is a cofactor in redox reactions and is particularly critical in mitochondria as it connects substrate oxidation by the tricarboxylic acid (TCA) cycle to adenosine triphosphate generation by the electron transport chain (ETC) and oxidative phosphorylation. While a mitochondrial NAD+ transporter has been identified in yeast, how NAD enters mitochondria in metazoans is unknown. Here, we mine gene essentiality data from human cell lines to identify MCART1 (SLC25A51) as coessential with ETC components. MCART1-null cells have large decreases in TCA cycle flux, mitochondrial respiration, ETC complex I activity, and mitochondrial levels of NAD+ and NADH. Isolated mitochondria from cells lacking or overexpressing MCART1 have greatly decreased or increased NAD uptake in vitro, respectively. Moreover, MCART1 and NDT1, a yeast mitochondrial NAD+ transporter, can functionally complement for each other. Thus, we propose that MCART1 is the long sought mitochondrial transporter for NAD in human cells.

Simple and robust polymer-based sensor for rapid cancer detection using serum.

We report a polymer-based sensor that rapidly detects cancer based on changes in serum protein levels. Using three ratiometric fluorescence outputs, this simple system identifies early stage and metastatic lung cancer with a high level of accuracy exceeding many biomarker-based assays, making it an attractive strategy for point-of-care testing.

SFXN1 is a mitochondrial serine transporter required for one-carbon metabolism.

One-carbon metabolism generates the one-carbon units required to synthesize many critical metabolites, including nucleotides. The pathway has cytosolic and mitochondrial branches, and a key step is the entry, through an unknown mechanism, of serine into mitochondria, where it is converted into glycine and formate. In a CRISPR-based genetic screen in human cells for genes of the mitochondrial pathway, we found sideroflexin 1 (SFXN1), a multipass inner mitochondrial membrane protein of unclear function. Like cells missing mitochondrial components of one-carbon metabolism, those null for SFXN1 are defective in glycine and purine synthesis. Cells lacking SFXN1 and one of its four homologs, SFXN3, have more severe defects, including being auxotrophic for glycine. Purified SFXN1 transports serine in vitro. Thus, SFXN1 functions as a mitochondrial serine transporter in one-carbon metabolism.

Chaotic printing: using chaos to fabricate densely packed micro- and nanostructures at high resolution and speed.

Nature generates densely packed micro- and nanostructures to enable key functionalities in cells, tissues, and other materials. Current fabrication techniques, due to limitations in resolution and speed, are far less effective at creating microstructures. Yet, the development of extensive amounts of surface area per unit volume will enable applications and manufacturing strategies not possible today. Here, we introduce chaotic printing-the use of chaotic flows for the rapid generation of complex, high-resolution microstructures. A simple and deterministic chaotic flow is induced in a viscous liquid, and its repeated stretching and folding action deforms an "ink" (i.e., a drop of a miscible liquid, fluorescent beads, or cells) at an exponential rate to render a densely packed lamellar microstructure that is then preserved by curing or photocrosslinking. This exponentially fast creation of fine microstructures exceeds the limits of resolution and speed of the currently available 3D printing techniques. Moreover, we show that the architecture of the microstructure to be created with chaotic printing can be predicted by mathematical modelling. We envision diverse applications for this technology, including the development of densely packed catalytic surfaces and highly complex multi-lamellar and multi-component tissue-like structures for biomedical and electronics applications.

Evolution and Clinical Translation of Drug Delivery Nanomaterials.

With the advent of technology, the role of nanomaterials in medicine has grown exponentially in the last few decades. The main advantage of such materials has been exploited in drug delivery applications, due to their effective targeting that in turn reduces systemic toxicity compared to the conventional routes of drug administration. Even though these materials offer broad flexibility based on targeting tissue, disease, and drug payload, the demand for more effective yet highly biocompatible nanomaterial-based drugs is increasing. While therapeutically improved and safe materials have been introduced in nanomedicine platforms, issues related to their degradation rates and bio-distribution still exist, thus making their successful translation for human use very challenging. Researchers are constantly improving upon novel nanomaterials that are safer and more effective not only as therapeutic agents but as diagnostic tools as well, making the research in the field of nanomedicine ever more fascinating. In this review stress has been made on the evolution of nanomaterials that have been approved for clinical applications by the United States Food and Drug Administration Agency (FDA).

Engineered 3D Cardiac Fibrotic Tissue to Study Fibrotic Remodeling.

Activation of cardiac fibroblasts into myofibroblasts is considered to play an essential role in cardiac remodeling and fibrosis. A limiting factor in studying this process is the spontaneous activation of cardiac fibroblasts when cultured on two-dimensional (2D) culture plates. In this study, a simplified three-dimensional (3D) hydrogel platform of contractile cardiac tissue, stimulated by transforming growth factor-ß1 (TGF-ß1), is presented to recapitulate a fibrogenic microenvironment. It is hypothesized that the quiescent state of cardiac fibroblasts can be maintained by mimicking the mechanical stiffness of native heart tissue. To test this hypothesis, a 3D cell culture model consisting of cardiomyocytes and cardiac fibroblasts encapsulated within a mechanically engineered gelatin methacryloyl hydrogel, is developed. The study shows that cardiac fibroblasts maintain their quiescent phenotype in mechanically tuned hydrogels. Additionally, treatment with a beta-adrenergic agonist increases beating frequency, demonstrating physiologic-like behavior of the heart constructs. Subsequently, quiescent cardiac fibroblasts within the constructs are activated by the exogenous addition of TGF-ß1. The expression of fibrotic protein markers (and the functional changes in mechanical stiffness) in the fibrotic-like tissues are analyzed to validate the model. Overall, this 3D engineered culture model of contractile cardiac tissue enables controlled activation of cardiac fibroblasts, demonstrating the usability of this platform to study fibrotic remodeling.