Lysinibacillus macroides-mediated control of cellulose-producing morphotype of Salmonella

BACKGROUND

Soil-dwelling human pathogens like Salmonella are transmitted by fresh produce such as tomato, spinach, onion and cabbage. With >2600 serovars, it is difficult to classify the good plant colonizers from the non-colonizers. Generally, soil microbiota are classified as autochthonous or zymogenous organisms, based on their ability to survive in soil. However, such information for soil-dwelling human pathogens is not available Thus there is a need to classify these organisms for designing a strategy to prevent their outbreak. Moreover, soil harbours a plethora of microbes, which can be screened for competitive organisms to control such human pathogens.

RESULTS

In this study, we examined whether the morphotype based on the attachment factors (e.g., cellulose and curli fimbri) of Salmonella was important for its colonization of roots. Secondly, we tracked the location of the bacteria in the plant cell. Interestingly, most of the epidermal cells occupied by Salmonella showed propidium iodide-positive nuclei. As an extension of the study, a screening of competitive rhizospheric bacteria was performed. One isolate, identified as Lysinibacillus macroides, was able to inhibit the biofilm of Salmonella and subsequently reduced its colonization on roots.

CONCLUSION

Based on this study, we classified the Rdar (red, dry and rough) morphotypes as good plant colonists. The ability to colonize and subsequent kill the live plant cell throws light on the zymogenous life cycle of soil-dwelling Salmonella. Additionally, Lysinibacillus macroides served as a biocontrol agent by reducing the burden of Salmonella in various vegetables. Such organisms can further be explored to prevent contamination of the food chain. © 2022 Society of Chemical Industry.

Electrochemical detection of hydrogen peroxide using micro and nanoporous CeO2 catalysts

In this research work, focus has been made on a glassy carbon electrode (GCE) modified commercial micro and synthesized nano-CeO₂ for the detection of hydrogen peroxide (H₂O₂). Firstly, CeO₂ nanoleaves were prepared by solvothermal route. Both commercially available micro CeO₂ and synthesized nano-CeO₂ structures were analyzed by different characterization techniques. The Raman spectra of synthesized nano CeO₂ has more oxygen vacancies than micro CeO₂. SEM images revealed that the synthesized CeO₂ acquired leaf-like morphology. The catalyst nano CeO₂ offered mesoporosity from nitrogen adsorption-desorption isotherms with massive sites of activation for increasing efficiency. Experiments on determining H₂O₂ using micro CeO₂ or nano-CeO₂/GCE was conducted using cyclic voltammetry (CV) and amperometry. Enhanced H₂O₂ reduction peak current with lower potential was observed in nano-CeO₂/GCE. The influence of scan rate and H₂O₂ concentration on the performance of nano-CeO₂/GCE were also studied. The obtained results have indicated that nano-CeO₂/GCE showed improved electrochemical sensing behavior towards the reduction of H₂O₂ than micro-CeO₂/GCE and bare GCE. A linear relationship was obtained over 0.001 μM-0.125 μM concentration of H₂O₂, with good sensitivity 141.96 μA μM^-1 and low detection limit of 0.4 nM. Hence, the present nano-CeO₂ system will have a great potential with solvothermal synthesis approach in the development of electrochemical sensors.

The ex vivo human translaminar autonomous system to study spaceflight associated neuro-ocular syndrome pathogenesis

Spaceflight-Associated Neuro-ocular Syndrome (SANS) is a significant unexplained adverse reaction to long-duration spaceflight. We employ an ex vivo translaminar autonomous system (TAS) to recreate a human ocular ground-based spaceflight analogue model to study SANS pathogenesis. To recapitulate the human SANS conditions, human ocular posterior segments are cultured in the TAS model for 14 days. Translaminar pressure differentials are generated by simulating various flow rates within intracranial pressure (ICP) and intraocular (IOP) chambers to maintain hydrostatic pressures of ICP: IOP (12:16, 15:16, 12:21, 21:16 mmHg). In addition, optic nerves are mechanically kinked by 6- and 10-degree tilt inserts for the ICP: IOP;15:16 mmHg pressure paradigm. The TAS model successfully maintains various pressure differentials for all experimental groups over 14 days. Post culture, we determine inflammatory and extracellular component expression changes within posterior segments. To further characterize the SANS pathogenesis, axonal transport capacity, optic nerve degeneration and retinal functional are measured. Identifiable pathogenic alterations are observed in posterior segments by morphologic, apoptotic, and inflammatory changes including transport and functional deficits under various simulated SANS conditions. Here we report our TAS model provides a unique preclinical application system to mimic SANS pathology and a viable therapeutic testing device for countermeasures.

Bacterial Outer Membrane Polysaccharide Export (OPX) Proteins Occupy Three Structural Classes with Selective β-Barrel Porin Requirements for Polymer Secretion

Secretion of high-molecular-weight polysaccharides across the bacterial envelope is ubiquitous, as it enhances prokaryotic survival in (a)biotic settings. Such polymers are often assembled by Wzx/Wzy- or ABC transporter-dependent schemes implicating outer membrane (OM) polysaccharide export (OPX) proteins in cell-surface polymer translocation. In the social predatory bacterium Myxococcus xanthus, the exopolysaccharide (EPS) pathway WzaX, major spore coat (MASC) pathway WzaS, and biosurfactant polysaccharide (BPS) pathway WzaB were herein found to be truncated OPX homologues of Escherichia coli Wza lacking OM-spanning α-helices. Comparative genomics across all bacteria (>91,000 OPX proteins identified and analyzed), complemented with cryo-electron tomography cell-envelope analyses, revealed such "truncated" WzaX/S/B architecture to be the most common among three defined OPX-protein structural classes independent of periplasm thickness. Fold recognition and deep learning revealed the conserved M. xanthus proteins MXAN_7418/3226/1916 (encoded beside wzaX/S/B, respectively) to be integral OM β-barrels, with structural homology to the poly-N-acetyl-d-glucosamine synthase-dependent pathway porin PgaA. Such bacterial porins were identified near numerous genes for all three OPX protein classes. Interior MXAN_7418/3226/1916 β-barrel electrostatics were found to match properties of their associated polymers. With MXAN_3226 essential for MASC export, and MXAN_7418 herein shown to mediate EPS translocation, we have designated this new secretion machinery component "Wzp" (i.e., Wz porin), with the final step of M. xanthus EPS/MASC/BPS secretion across the OM now proposed to be mediated by WzpX/S/B (i.e., MXAN_7418/3226/1916). Importantly, these data support a novel and widespread secretion paradigm for polysaccharide biosynthesis pathways in which those containing OPX components that cannot span the OM instead utilize β-barrel porins to mediate polysaccharide transport across the OM. IMPORTANCE Diverse bacteria assemble and secrete polysaccharides that alter their physiologies through modulation of motility, biofilm formation, and host immune system evasion. Most such pathways require outer membrane (OM) polysaccharide export (OPX) proteins for sugar-polymer transport to the cell surface. In the prototypic Escherichia coli Group-1-capsule biosynthesis system, eight copies of this canonical OPX protein cross the OM with an α-helix, forming a polysaccharide-export pore. Herein, we instead reveal that most OPX proteins across all bacteria lack this α-helix, raising questions as to the manner by which most secreted polysaccharides actually exit cells. In the model developmental bacterium Myxococcus xanthus, we show this process to depend on OPX-coupled OM-spanning β-barrel porins, with similar porins encoded near numerous OPX genes in diverse bacteria. Knowledge of the terminal polysaccharide secretion step will enable development of antimicrobial compounds targeted to blocking polymer export from outside the cell, thus bypassing any requirements for antimicrobial compound uptake by the cell.

Varied Clinical Presentation and Management of Calvarial Metastases

Calvarium and skull base can be affected by a variety of benign, tumor-like, and malignant processes. Skull metastases (SMs) may be located in any layer of the skull and may be incidental or present with neurological symptoms during the diagnostic workup. In the present study, we discuss the occurrence of SMs from various index malignancies and their myriad clinical presentation. This data-based study includes patients of bone metastases between June 2018 and July 2020. Patients with skull bone metastases were recognized, and location of primary site, their clinical presentation, and management strategy were noted. Ten patients with skull bone metastases were identified during this period. Four patients had skull base location with clinical manifestation as syndromes. Six patients had primary from breast cancer, three from Ewing's sarcoma, and one from lung cancer. Management varied according to the primary site and symptoms of each patient. SM, though not rare, is often diagnosed incidentally but presents diagnostic and management challenges in the patient with cancer.

Potential of cytochrome P450, a family of xenobiotic metabolizing enzymes, in cancer therapy

SIGNIFICANCE

Targeted cancer therapy with minimal off-target consequences has shown promise for some cancer types. Although cytochrome P450 (CYP) consists of 18 families, CYP1-4 families play key role in metabolizing xenobiotics and cancer drugs. This eventually affects the process of carcinogenesis, treatment outcome, and cancer drug resistance. Differential overexpression of CYPs in transformed cells, together with phenotypic alterations in tumors, presents a potential for therapeutic intervention.

RECENT ADVANCES

Recent advances in molecular tools and information technology have helped utilize CYPs as cancer targets. The precise expression in various tumors, X-ray crystal structures, improved understanding of the structure-activity relationship, and new approaches in the development of prodrugs have supported the ongoing efforts to develop CYPs-based drugs with a better therapeutic index.

CRITICAL ISSUES

Narrow therapeutic index, off-target effects, drug resistance, and tumor heterogeneity limit the benefits of CYP-based conventional cancer therapies. In this review, we address the CYP1-4 families as druggable targets in cancer. An emphasis is given to the CYP expression, function, and the possible mechanisms that drive expression and activity in normal and transformed tissues. The strategies that inhibit or activate CYPs for therapeutic benefits are also discussed.

FUTURE DIRECTIONS

Efforts are needed to develop more selective tools that will help comprehend molecular and metabolic alterations in tumor tissues with biological end-points in relation to CYPs. This will eventually translate to developing more specific CYP inhibitors/inducers.

Aflatoxin B1 Toxicity and Protective Effects of Curcumin: Molecular Mechanisms and Clinical Implications

One of the most significant classes of mycotoxins, aflatoxins (AFTs), can cause a variety of detrimental outcomes, including cancer, hepatitis, aberrant mutations, and reproductive issues. Among the 21 identified AFTs, aflatoxin B1 (AFB1) is the most harmful to humans and animals. The mechanisms of AFB1-induced toxicity are connected to the generation of excess reactive oxygen species (ROS), upregulation of CYP450 activities, oxidative stress, lipid peroxidation, apoptosis, mitochondrial dysfunction, autophagy, necrosis, and inflammatory response. Several signaling pathways, including p53, PI3K/Akt/mTOR, Nrf2/ARE, NF-κB, NLRP3, MAPKs, and Wnt/β-catenin have been shown to contribute to AFB1-mediated toxic effects in mammalian cells. Curcumin, a natural product with multiple therapeutic activities (e.g., anti-inflammatory, antioxidant, anticancer, and immunoregulation activities), could revise AFB1-induced harmful effects by targeting these pathways. Therefore, the potential therapeutic use of curcumin against AFB1-related side effects and the underlying molecular mechanisms are summarized. This review, in our opinion, advances significant knowledge, sparks larger discussions, and drives additional improvements in the hazardous examination of AFTs and detoxifying the application of curcumin.

Preclinical Safety Assessment of Chemically Cross-Linked Modified Mandua Starch: Acute and Sub-Acute Oral Toxicity Studies in Swiss Albino Mice

In the present era, 28 days of repeated-dose-toxicity study following the Organization for Economic Cooperation and Development (OECD) guidelines 407 is compulsory for every drug to go through phase 1 clinical trials. The increasing demand for high-resistant starch containing nutraceuticals and the applicability of modified starch in development of targeted drug delivery inspired us to investigate the toxic profile of mandua starch chemically cross-linked by epichlorohydrin and compare it with alkali-isolated starch in healthy adult Swiss albino mice, which can be the first step for exploring the use of epichlorohydrin-cross-linked mandua starch (ECC-MS) as a pharmaceutical excipient. Histopathological examinations of the kidney and liver did not expose noteworthy abnormalities in the treated mice. There were no clinical and mortality symptoms of toxicity observed during the repeated-dose-toxicity study. The oral consumption of ECC-MS did not pose any harm as it was neither lethal nor had any harmful hematological, biochemical, psychological, anatomical, and behavioral effects. The use of ECC-MS and alkali-isolated mandua starch (AMS) was found safe at a dose of 2000 mg/kg body weight in the acute toxicity study and at doses of 2000, 1500, and 1000 mg/kg body weight in the sub-acute toxicity study as no detrimental effects were observed after oral administration in mice for 14 and 28 days, respectively.

GO/TiO2-Related Nanocomposites as Photocatalysts for Pollutant Removal in Wastewater Treatment

Water pollution has been a prevalent issue globally for some time. Some pollutants are released into the water system without treatment, making the water not suitable for consumption. This problem may lead to more grave problems in the future including the destruction of the ecosystem along with the organisms inhabiting it, and illness and diseases endangering human health. Conventional methods have been implemented to remove hazardous pollutants such as dyes, heavy metals, and oil but are incapable of doing so due to economic restraints and the inability to degrade the pollutants, leading to secondary pollution. Photocatalysis is a more recently applied concept and is proven to be able to completely remove and degrade pollutants into simpler organic compounds. Titanium dioxide (TiO₂) is a fine example of a photocatalyst owing to its cost-effectiveness and superb efficiency. However, issues such as the high recombination rate of photogenerated electrons along with positive holes while being only limited to UV irradiation need to be addressed. Carbonaceous materials such as graphene oxide (GO) can overcome such issues by reducing the recombination rate and providing a platform for adsorption accompanied by photocatalytic degradation of TiO₂. The history and development of the synthesis of GO will be discussed, followed by the methods used for GO/TiO₂ synthesis. The hybrid of GO/TiO₂ as a photocatalyst has received some attention in the application of wastewater treatment due to its efficiency and it being environmentally benign. This review paper thereby aims to identify the origins of different pollutants followed by the sickness they may potentially inflict. Recent findings, including that GO/TiO₂-related nanocomposites can remove pollutants from the water system, and on the photodegradation mechanism for pollutants including aromatic dyes, heavy metal and crude oil, will be briefly discussed in this review. Moreover, several crucial factors that affect the performance of photocatalysis in pollutant removal will be discussed as well. Therefore, this paper presents a critical review of recent achievements in the use of GO/TiO₂-related nanocomposites and photocatalysis for removing various pollutants in wastewater treatment.

Focus stacking in non-contact dermoscopy

Dermoscopy is the main tool for early detection of skin cancer. Non-contact dermoscopes often suffer from a small depth of field leading to images of skin topographies with regions that are not in focus. We aim to provide an easy-to-implement focus stacking-based approach to ensure all-in-focus images from a non-contact dermoscope. Further, we aim to extract additional information about the skin topography from the image stacks. The focus stacking procedure itself is implemented in a non-contact dermoscope with an electrically adjustable focus realized by using a tunable liquid lens. We show that all-in-focus imaging is possible for non-contact dermoscopy and deliver a method to extract topographical information for dermatologists from the acquired image stacks. Our finding indicate that the approach can be valuable for non-contact dermoscopic examination as well as for the early detection of skin diseases such as cancer as it possible to derive hyperfocus images and information on the skin topography. With this, we were able to develop a software for the acquisition of the raw image data and its processing into a high resolution hyperresolution dermoscopic image. In the next steps, we plan to apply the approach in the clinical environment for skin cancer diagnostics or imaging of inflammatory skin diseases.

Evaluation of Azido 3-Deoxy-d-manno-oct-2-ulosonic Acid (Kdo) Analogues for Click Chemistry-Mediated Metabolic Labeling of Myxococcus xanthus DZ2 Lipopolysaccharide

Metabolic labeling paired with click chemistry is a powerful approach for selectively imaging the surfaces of diverse bacteria. Herein, we explored the feasibility of labeling the lipopolysaccharide (LPS) of Myxococcus xanthus-a Gram-negative predatory social bacterium known to display complex outer membrane (OM) dynamics-via growth in the presence of distinct azido (-N3) analogues of 3-deoxy-d-manno-oct-2-ulosonic acid (Kdo). Determination of the LPS carbohydrate structure from strain DZ2 revealed the presence of one Kdo sugar in the core oligosaccharide, modified with phosphoethanolamine. The production of 8-azido-8-deoxy-Kdo (8-N3-Kdo) was then greatly improved over previous reports via optimization of the synthesis of its 5-azido-5-deoxy-d-arabinose precursor to yield gram amounts. The novel analogue 7-azido-7-deoxy-Kdo (7-N3-Kdo) was also synthesized, with both analogues capable of undergoing in vitro strain-promoted azide-alkyne cycloaddition (SPAAC) "click" chemistry reactions. Slower and faster growth of M. xanthus was displayed in the presence of 8-N3-Kdo and 7-N3-Kdo (respectively) compared to untreated cells, with differences also seen for single-cell gliding motility and type IV pilus-dependent swarm community expansion. While the surfaces of 8-N3-Kdo-grown cells were fluorescently labeled following treatment with dibenzocyclooctyne-linked fluorophores, the surfaces of 7-N3-Kdo-grown cells could not undergo fluorescent tagging. Activity analysis of the KdsB enzyme required to activate Kdo prior to its integration into nascent LPS molecules revealed that while 8-N3-Kdo is indeed a substrate of the enzyme, 7-N3-Kdo is not. Though a lack of M. xanthus cell aggregation was shown to expedite growth in liquid culture, 7-N3-Kdo-grown cells did not manifest differences in intrinsic clumping relative to untreated cells, suggesting that 7-N3-Kdo may instead be catabolized by the cells. Ultimately, these data provide important insights into the synthesis and cellular processing of valuable metabolic labels and establish a basis for the elucidation of fundamental principles of OM dynamism in live bacterial cells.

Patterns and outcomes of cardiovascular emergency department encounters for men and women in the USA

Aims

We described sex-differential disease patterns and outcomes of over 20.6 million cardiovascular emergency department (ED) encounters in the USA.

Methods and results

We analysed primary cardiovascular encounters from the Nationwide Emergency Department Sample (between 2016–2018). We grouped the documented cardiovascular diagnoses into 15 disease categories. The sample included 48.7% women; average age was 67 [54,78] years. Men had greater overall baseline co-morbidity burden; however, women had higher rates of obesity, hypertension, and cerebrovascular disease. For women, the most common ED encounters were essential hypertension (16.0%), hypertensive heart or kidney disease (14.1%), and atrial fibrillation (AF)/flutter (10.2%). For men, the most common encounters were hypertensive heart or kidney disease (14.7%), essential hypertension (10.8%), and acute myocardial infarction (AMI, 10.7%). Women were more likely to present with essential hypertension, hypertensive crisis, AF/flutter, supraventricular tachycardia, pulmonary embolism, or ischaemic stroke. Men were more likely to present with AMI or cardiac arrest. In logistic regression models adjusted for baseline covariates, women with intracranial haemorrhage had higher risk of hospitalisation and death. Women with ischaemic stroke had higher risk of hospitalisation and death in ED. Women presenting with pulmonary embolism were less likely to be hospitalised but were more likely to die. Women with aortic aneurysm/dissection had higher risk of hospitalisation and death. Men were more likely to die following presentations with hypertensive heart or kidney disease, AF/flutter, AMI, or cardiac arrest.

Conclusion

In this large nationally representative sample of cardiovascular ED presentations, we demonstrate significant sex differences in disease distribution, hospitalisation, and death.

Funding Acknowledgement

Type of funding sources: None.

Effects of high glutamate concentrations on mitochondria of human neuroblastoma SH-SY5Y cells

BACKGROUND

The excess amount of glutamate in neurons is associated with the excitotoxicity and neurodegenerative diseases. Glutamate induces neurotoxicity primarily by immense influx of Ca²⁺ arising from overstimulation of the NMDA subtype of glutamate receptors. The neuronal death induced by the overstimulation of glutamate receptors depends critically on a sustained increase in mitochondrial Ca²⁺ influx and impairment in mitochondrial functions. The mitochondrial impairment is an important contributor to the glutamate-induced neuronal toxicity and thus provides an important target for the intervention. The present study investigates the effects of high glutamate concentrations on mitochondrial functions.

RESULTS

Here, we have shown that the higher concentration of glutamate treatment caused a significant elevation in the N-methyl-D-aspartate (NMDA) receptors expression and elevated the intra-mitochondrial calcium accumulation in SHSY5Y neuronal cells. As a result of an accumulation of intra-mitochondrial calcium, there is a concentration-dependent elevation in ROS in the mitochondria. Tyrosine nitration of several mitochondrial proteins was increased while the mitochondrial membrane potential was dissipated. Furthermore, glutamate treatments also resulted in mitochondrial membrane permeability transition.

CONCLUSIONS

These findings suggest that treatment of high glutamate concentration causes impairment of mitochondrial functions by an increase in intra-mitochondrial calcium, ROS production, dissipation of mitochondrial membrane potential and mitochondrial permeability transition pore opening in human neuroblastoma SHSY5Y cells.

Hypoalbuminemia and not undernutrition predicts high-dose methotrexate-induced nephrotoxicity in children with acute lymphoblastic leukemia in resource-constrained centers

BACKGROUND

The standard practice to mitigate high-dose methotrexate (HD-MTX)-induced nephrotoxicity (HMN) in acute lymphoblastic leukemia (ALL) is to monitor levels until serum MTX falls below a predefined threshold. It is not feasible in most resource-constrained centers. Literature on the various factors affecting HMN in these centers is limited, retrospective, and heterogeneous. Though hypoalbuminemia has been postulated as a risk factor for HMN, the relationship of undernutrition with HMN has not been studied.

PROCEDURE

This prospective observational study consecutively enrolled children < 12 years old with ALL receiving HD-MTX. Children with preexisting renal disease and exposed to nephrotoxic drugs two weeks preceding HD-MTX infusion were excluded. HD-MTX was administered over 24 hours (BFM-2009 protocol) with 12 hours of prehydration. Solitary MTX levels at 36 hours (MTX36) were outsourced, and 6-8 doses of leucovorin were given six-hourly. Hydration was continued till last dose of leucovorin. Various factors affecting HMN (rise in creatinine to 1.5 times baseline) were recorded: age, sex, type of ALL, risk group of ALL, first dose of MTX, dose of MTX, undernourishment, serum protein, and albumin along with C-reactive protein and MTX36 levels.

RESULTS

Forty-four children who received 150 HD-MTX cycles were analyzed. HMN was seen in 14% of cycles. On univariate analysis, undernourishment, MTX36 levels, hypoproteinemia, and hypoalbuminemia were significantly associated with HMN. On multivariate analysis, hypoalbuminemia and MTX36 levels significantly predicted the development of HMN with odds ratios of 4.71 and 1.45.

CONCLUSION

Hypoalbuminemia and solitary serum MTX levels predict HMN in centers where serial MTX level monitoring is not feasible.

Lignocellulolytic enzymes from Aspergillus allahabadii for efficient bioconversion of rice straw into fermentable sugars and biogas

The study was aimed at developing lignocellulolytic strain capable of efficient hydrolysis of mild alkali deacetylated (MAD) rice straw. The valorisation of lignin rich black liquor obtained during pre-treatment of rice straw into biogas was also evaluated. Study reports highly proficient cellulolytic Aspergillus allahabadii strain harbouring a spectrum of CAZymes based on comparative genome wide analysis that was subjected to strain breeding for developing a hyper producing strain. The secretome analysis showed up-modulation and several folds increase in the CAZyme activities in the culture extracts of the developed strain MAN 40 when compared to parent. The cellulolytic cocktail of the developed strain showed 1.52 folds higher saccharification of MAD rice straw when compared to Cellic CTec 3. Moreover, in-situ addition of cellulases derived from developed strains resulted in ∼3.7 folds higher methane production during anaerobic digestion of mixture of lignin rich black liquor and differently treated rice straw.

Furostanol saponins from Asparagus racemosus as potential hypoglycemic agents

Bioactivity guided phytochemical investigation led to isolation of six undescribed furostanol saponins, furoasparoside A-F along with five known compounds, gallic acid, methyl gallate, quercetin-3-O-β-glucopyranoside, liquiritigenin 4^׳-O-β-apiofuranosyl-(1 → 2)-β-glucopyranoside and β-glucogallin for the first time from the roots of Asparagus racemosus. Isolated saponins were screened for their antidiabetic potential in L6-GLUT4myc myotubes in vitro followed by an in vivo evaluation in streptozocin-induced diabetic rats and db/db mice. Furoasparoside E produced a notable decrease in the postprandial blood glucose profile, in leptin receptor-deficient db/db mice, type 2 diabetes model. The effect of furoasparoside E on GLUT4 translocation was found to be mediated by the AMPK-dependent signaling pathway in L6-GLUT4myc myotubes. Moreover, it emerged as a stable plant metabolite with higher bioavailability and efficacy in in vivo pharmacokinetic studies. Therefore, these studies indicated that furoasparoside E may serve as a propitious lead for the management of type 2 diabetes and its secondary complications from natural source.

Visible-light driven dual heterojunction formed between g-C3N4/BiOCl@MXene-Ti3C2 for the effective degradation of tetracycline

In the present study, we have successfully formulated a dual heterojunction of g-C₃N₄/BiOCl@MXene-Ti₃C₂ (GCBM) which was found to be highly active in the visible region. GCBM was found to be highly efficient for the degradation of an antibiotic, tetracycline (TC) as compared to the individual constituting units; g-C₃N₄ and BiOCl. Maximum of 97% TC degradation rate was obtained within 90 min of visible light irradiation for initial concentration of 10 mg/L of TC. Optical analysis exhibited that the synthesized heterojunction showed high absorption in the complete spectrum. The reactive species specified by the scavenger study showed the major involvement of ^•O₂^- and ^•OH radicals. The charge transfer mechanism showed that 2 schemes were majorly involvement in which Z-scheme was formed between g-C₃N₄ and BiOCl and Schottky junction was formed between g-C₃N₄ and Mxene-Ti₃C₂. The formation of Schottky junction helped in inhibiting the back transfer of photogenerated charges and thus, helped in reducing the recombination rate. The synthesized photocatalyst was found to be highly reusable and was studied for consecutive 5 cycles that generalized the high proficiency even after repetitive cycles.

Evaluation of GeneXpert and liquid culture for detection of Mycobacterium tuberculosis in pediatric patients

PURPOSE

Evaluation of GeneXpert in comparison to liquid culture using Mycobacteria Growth Indicator Tube (MGIT) as gold standard for detection of Mycobacterium tuberculosis (MTB) in children.

METHODS

A total of 8123 samples, both pulmonary (5830) and extra pulmonary (2293) received from pediatric patients were processed for Acid Fast Bacilli (AFB) smear, GeneXpert and MGIT culture simultaneously.

RESULTS

Out of 8123 samples, 493 (6.1%) samples were found positive by GeneXpert and 508 (6.2%) samples by MGIT culture, 371 (4.6%) were found positive by both GeneXpert and MGIT culture. MGIT detected 137 (1.7%) extra positive than GeneXpert while GeneXpert detected 122 (1.5%) extra samples more positive than by MGIT. Sensitivity of GeneXpert was 73% and concordance between both methods was 96.8%. Rifampicin resistance was found in 49 (9.9%) samples among MTB positive by GeneXpert. Turnaround time for GeneXpert was approx. 2 ​h and for MGIT, it was 12-28 days.

CONCLUSION

Good sensitivity (73%) and concordance (96.8%) were observed for GeneXpert against MGIT culture in this study. GeneXpert can simultaneously detect MTB and rifampicin resistance in less than 2 ​h while MGIT takes 12-28 days for MTB detection only.

Combining Feature Correspondence With Parametric Chamfer Alignment: Hybrid Two-Stage Registration for Ultra-Widefield Retinal Images

We propose a novel hybrid framework for registering retinal images in the presence of extreme geometric distortions that are commonly encountered in ultra-widefield (UWF) fluorescein angiography. Our approach consists of two stages: a feature-based global registration and a vessel-based local refinement. For the global registration, we introduce a modified RANSAC (random sample and consensus) that jointly identifies robust matches between feature keypoints in reference and target images and estimates a polynomial geometric transformation consistent with the identified correspondences. Our RANSAC modification particularly improves feature point matching and the registration in peripheral regions that are most severely impacted by the geometric distortions. The second local refinement stage is formulated in our framework as a parametric chamfer alignment for vessel maps obtained using a deep neural network. Because the complete vessel maps contribute to the chamfer alignment, this approach not only improves registration accuracy but also aligns with clinical practice, where vessels are typically a key focus of examinations. We validate the effectiveness of the proposed framework on a new UWF fluorescein angiography (FA) dataset and on the existing narrow-field FIRE (fundus image registration) dataset and demonstrate that it significantly outperforms prior retinal image registration methods in accuracy. The proposed approach enhances the utility of large sets of longitudinal UWF images by enabling: (a) automatic computation of vessel change metrics such as vessel density and caliber, and (b) standardized and co-registered examination that can better highlight changes of clinical interest to physicians.

Triple-negative breast cancer metastasis involves complex epithelial-mesenchymal transition dynamics and requires vimentin

Triple-negative breast cancer (TNBC) is an aggressive subtype associated with early metastatic recurrence and worse patient outcomes. TNBC tumors express molecular markers of the epithelial-mesenchymal transition (EMT), but its requirement during spontaneous TNBC metastasis in vivo remains incompletely understood. We demonstrated that spontaneous TNBC tumors from a genetically engineered mouse model (GEMM), multiple patient-derived xenografts, and archival patient samples exhibited large populations in vivo of hybrid E/M cells that lead invasion ex vivo while expressing both epithelial and mesenchymal characteristics. The mesenchymal marker vimentin promoted invasion and repressed metastatic outgrowth. We next tested the requirement for five EMT transcription factors and observed distinct patterns of utilization during invasion and colony formation. These differences suggested a sequential activation of multiple EMT molecular programs during the metastatic cascade. Consistent with this model, our longitudinal single-cell RNA analysis detected three different EMT-related molecular patterns. We observed cancer cells progressing from epithelial to hybrid E/M and strongly mesenchymal patterns during invasion and from epithelial to a hybrid E/M pattern during colony formation. We next investigated the relative epithelial versus mesenchymal state of cancer cells in both GEMM and patient metastases. In both contexts, we observed heterogeneity between and within metastases in the same individual. We observed a complex spectrum of epithelial, hybrid E/M, and mesenchymal cell states within metastases, suggesting that there are multiple successful molecular strategies for distant organ colonization. Together, our results demonstrate an important and complex role for EMT programs during TNBC metastasis.

Acute Reconstruction of Traumatic Zone IV Re-tear of Extensor Hallucis Longus Tendon using Extensor Hallucis Brevis loop Technique - A Mid-term Follow-up Case Report

Introduction

The present case report describes an acute reconstruction of extensor hallucis longus (EHL) tendon with defect treated using looped extensor hallucis brevis (EHB) tendon graft.

Case Report

A 40 year male manual labor had an acute traumatic EHL tear which was repaired at a primary health care center. After 2 days, the patient felt a sudden click and a re-tear at zone IV of EHL. Since there was a defect of 3.5 cm which was not amenable for primary repair, EHB graft was used for the reconstruction in a loop fashion. The foot and ankle disability index score was 95.2 at 2 years follow-up with grade 4 + power.

Conclusion

EHB graft is a good alternative to other autografts for extensor hallucis longus reconstructions with good clinical and functional outcomes.

Registration of polarimetric images for in vivo skin diagnostics

SIGNIFICANCE

Mueller matrix (MM) polarimetry is a promising tool for the detection of skin cancer. Polarimetric in vivo measurements often suffer from misalignment of the polarimetric images due to motion, which can lead to false results.

AIM

We aim to provide an easy-to-implement polarimetric image data registration method to ensure proper image alignment.

APPROACH

A feature-based image registration is implemented for an MM polarimeter for phantom and in vivo human skin measurements.

RESULTS

We show that the keypoint-based registration of polarimetric images is necessary for in vivo skin polarimetry to ensure reliable results. Further, we deliver an efficient semiautomated method for the registration of polarimetric images.

CONCLUSIONS

Image registration for in vivo polarimetry of human skin is required for improved diagnostics and can be efficiently enhanced with a keypoint-based approach.

Towards Reviewing an Immediate Impact of COVID-19 on the Integrative World Economy

The coronavirus (CoV) belongs to Severe Acute Respiratory Syndrome (SARS) species that lead to infection, causing illness, starting from common cold to some serious sickness. Finally, on 11 March 2020, the WHO Director-General Dr. Tedros Adhanom Ghebreyesus announced the outbreak as a pandemic. As the fear and ambiguity rose among companies and firms, the profit rate seemed to be lower due to the Covid-19 global impact, say nearly US$6 trillion in wealth from 24th to 28 February 2020 of the stock market has been wiped out. There was a great decrease in value over the S&P index, which abolished over $5 trillion in the same week. However, the largest ten companies of S&P faced a loss of $1.4 trillion. The investors make an analytical prediction that firms' profits may drop in response to the impact of coronavirus. Our prime focus is on the importance of digital business practices and how different sectors have been affected in terms of economic loss during this pandemic outbreak in this paper.

HRS phosphorylation drives immunosuppressive exosome secretion and restricts CD8+ T-cell infiltration into tumors

The lack of tumor infiltration by CD8⁺ T cells is associated with poor patient response to anti-PD-1 therapy. Understanding how tumor infiltration is regulated is key to improving treatment efficacy. Here, we report that phosphorylation of HRS, a pivotal component of the ESCRT complex involved in exosome biogenesis, restricts tumor infiltration of cytolytic CD8⁺ T cells. Following ERK-mediated phosphorylation, HRS interacts with and mediates the selective loading of PD-L1 to exosomes, which inhibits the migration of CD8⁺ T cells into tumors. In tissue samples from patients with melanoma, CD8⁺ T cells are excluded from the regions where tumor cells contain high levels of phosphorylated HRS. In murine tumor models, overexpression of phosphorylated HRS increases resistance to anti-PD-1 treatment, whereas inhibition of HRS phosphorylation enhances treatment efficacy. Our study reveals a mechanism by which phosphorylation of HRS in tumor cells regulates anti-tumor immunity by inducing PD-L1⁺ immunosuppressive exosomes, and suggests HRS phosphorylation blockade as a potential strategy to improve the efficacy of cancer immunotherapy.

Polysomnographic Characteristics of the Patients Having Chronic Insomnia and Obstructive Sleep Apnea: Evidence for Paradoxical Insomnia and Comorbid Insomnia with OSA (COMISA)

BACKGROUND

Sleep state misperception (SSM) is seen among patients with obstructive sleep apnea (OSA) as well as those having insomnia. Moreover, OSA and insomnia can also be comorbid. This study aims at finding the proportion of SSM and "Comorbid Insomnia with OSA" (COMISA) among patients of OSA and chronic insomnia. Macroachitecture of sleep was also compared across groups.

METHODS

This study utilized the retrospective laboratory and medical records of two groups of patients: chronic insomnia and OSA. Sleep disorders were diagnosed according to standard criteria. Daytime sleepiness was examined using the Epworth Sleepiness Scale. Diagnosis of SSM was based on the difference between subjective and objective sleep onset latency (Subjective SOL > 1.5 × Objective SOL).

RESULTS

Sixteen adult subjects were included in each group. Based on the difference between subjective and objective sleep onset latency, SSM was reported by 62.5% subjects of chronic insomnia and 56.25% subjects having OSA (OR = 1.29; 95% CI = 0.31-5.33; P = 0.79). The proportion of COMISA in subjects with chronic insomnia was 18% and among subjects with OSA, it was 43%. Effect size for the proportion was calculated as odds ratio (33.96; 95% CI = 7.48-154.01; P < 0.0002). Thus, the odds for COMISA were higher among subjects with OSA than those with chronic Insomnia. The three groups (OSA, COMISA and Chronic Insomnia) were comparable with regard to the macro-architecture of sleep.

CONCLUSION

SSM is common among subjects with OSA and chronic insomnia. COMISA was commoner among patients with OSA compared to those with chronic insomnia. Macro-architecture of sleep is comparable among groups.

Clinical evaluation of bioactive resin-modified glass ionomer and giomer in restoring primary molars: A randomized, parallel-group, and split-mouth controlled clinical study

AIM

This study aims to evaluate and compare the clinical performance of two restorative materials - bioactive resin-modified glass ionomer (ACTIVA BioACTIVE restorative) and giomer hybrid composite (Beautifil Flow Plus) in restoring class I carious primary molars.

MATERIALS AND METHODS

The split-mouth randomized controlled study was conducted on 100 primary molars from 50 children (28 - males, 22 - females) from 50 children in age range of 5-9 years (Mean-7.29±1.34) with at least two occlusal carious lesions on either maxillary or mandibular primary molars. Each child had both the control and the experimental teeth restored with respective restorative materials, Group I (Control, n = 50) → Giomer, Group II (Experimental, n = 50) → Bioactive resin-modified glass ionomer. The restorations were evaluated by two independent investigators using modified United State Public Health Service criteria at immediate postoperative, 6 months, and 12 months. The Chi-square test was used for the statistical analysis after collecting the data.

RESULTS

At the 12-month follow-up, 33 children (66 teeth) reported with an attrition rate of 33%. The color match between the groups was not statistically significant at all intervals. The marginal discoloration, marginal integrity, anatomic form, and retention had no significant difference at 6 months. But at 12 months, there was a statistically significant difference between the groups with p value of 0.04,<0.001,<0.02 and <0.001 respectively. respectively. At 12 months, there was no postoperative sensitivity in both groups.

CONCLUSION

Bioactive resin-modified glass ionomer with enhanced properties can be used as an effective restorative material, especially in children with excessive salivation.

Mid-term Outcome of a Chronic Traumatic Bony Avulsion of Distal Triceps Treated with Tension Band Wiring Technique - A Case Report

Introduction

Ideal treatment of chronic distal triceps rupture is controversial due to low occurrence of this injury. We report a unique case of chronic traumatic distal triceps rupture which was missed initially and then treated by tension band wiring.

Case Report

A 30-year-old manual labor presented with 2-month-old injury and difficulty in complete extension of the elbow which was initially managed conservatively. He was clinic-radiologically diagnosed as complete distal triceps bony avulsion tear. He was operated using tension band wiring technique. His DASH score at the end of 2-year follow-up was 5.4 indicating excellent outcome.

Conclusion

A strong clinical suspicion should be raised about triceps injury in patients with chronic elbow pain and weak extension. Tension band wiring technique gives good clinical and functional outcome in patients with bony avulsion along with distal triceps tear.

Primer for Designing Main Protease (Mpro) Inhibitors of SARS-CoV-2

The COVID-19 outbreak has been devastating, with hundreds of millions of infections and millions of deaths reported worldwide. In response, the application of structure-activity relationships (SAR) upon experimentally validated inhibitors of SARS-CoV-2 main protease (Mpro) may provide an avenue for the identification of new lead compounds active against COVID-19. Upon the basis of information gleaned from a combination of reported crystal structures and the docking of experimentally validated inhibitors, four "rules" for designing potent Mpro inhibitors have been proposed. The aim here is to guide medicinal chemists toward the most probable hits and to provide guidance on repurposing available structures as Mpro inhibitors. Experimental examination of our own previously reported inhibitors using the four "rules" identified a potential lead compound, the cathepsin inhibitor GB111-NH2, that was 2.3 times more potent than SARS-CoV-2 Mpro inhibitor N3.

A Tandem Semipinacol Rearrangement/Aldehyde Arylation or Alkylation of Trisubstituted 2,3-Epoxy Alcohols with Grignard Reagents for Functionalized 1,3-Diols

A tandem semipinacol rearrangement/aldehyde arylation or alkylation reaction leading to formation of functionalized 1,3-diols bearing three consecutive tertiary stereocenters is identified from the reaction of various new trisubstituted 2,3-epoxy alcohols with numerous Grignard reagents. This reaction is useful for stereoselective construction of three consecutive tertiary stereocenters. The observed 1,3-diols exist in the anti configuration, which is confirmed by two-dimensional nuclear Overhauser effect spectroscopy, the crystal structure of acetonide of 1,3-diol analogue 3ai, and further density functional theory studies.

Case Report: Secondary Hemophagocytic Lymphohistiocytosis (sHLH) and Candida auris Fungemia in Post-acute COVID-19 Syndrome: A Clinical Challenge

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection causes a disease (COVID-19) with multisystem involvement. The world is now entering a phase of post-COVID-19 manifestations in this pandemic. Secondary hemophagocytic lymphohistiocytosis (sHLH) is a life-threatening hyperinflammatory event triggered by viral infections, including SARS-CoV-2. Both Multisystem Inflammatory Syndrome-Adults (MIS-A) and Cytokine Storm Syndrome (CSS) are considered close differentials of sHLH and add to the spectrum of Post-acute COVID-19 syndrome (PACS). In this report, we presented the case of a middle-aged Asian man who was initially discharged upon recovery from severe COVID-19 infection after 17 days of hospitalization to a private institute and later came to our hospital 13 days post-discharge. Here, he was diagnosed with sHLH, occurring as an extension of CSS, with delayed presentation falling within the spectrum of PACS. The diagnosis of sHLH was made holistically with the HLH-2004 criteria. Our patient initially responded to intravenous immunoglobulin (IVIG) and dexamethasone, later complicated by disseminated Candida auris infection and had a fatal outcome. Though many cases of HLH during active COVID-19 and a few cases post COVID-19 recovery have been reported, based on H-score, which has limitations as a diagnostic tool. We report the first case report of post-COVID-19 sHLH using the HLH-2004 criteria, complicated by disseminated Candidemia, emphasizing that the care of patients with COVID-19 does not conclude at the time of hospital discharge. We highlight the importance of surveillance in the post-COVID phase for early detection of sHLH which may predispose to fatal opportunistic infections (OIs).

Perfusion Strategies for Bivalirudin Anticoagulation: AIIMS Protocol

Anticoagulation strategies for cardiac surgery are witnessing a change with the identification of serious limitations of heparin, including development of resistance in 3 to 13% of patients undergoing cardiac surgery and heparin-induced thrombocytopenia/thrombosis syndrome in 1 to 5.5% of patients. Heparin alternatives have a potential role in these scenarios. Bivalirudin, a reversible direct thrombin inhibitor, has an onset time of 2 to 4 minutes and half-life of 25 minutes, is eliminated mainly by a proteolytic mechanism, does not require antithrombin III for effect, and is nonimmunogenic. The considerations for extracorporeal circulation are peculiar with its use, and this article outlines the aspects of initiating, maintaining, and terminating cardiopulmonary bypass and extracorporeal membrane oxygenation with bivalirudin as the anticoagulant.

Nitrogen Fixation Influenced by Phosphorus and Nitrogen Availability in the Benthic Bloom-forming Cyanobacterium Hydrocoleum sp. Identified in a Temperate Marine Lagoon

The nitrogen-fixing, non-heterocystous cyanobacterium Hydrocoleum sp. (Oscillatoriales) is a common epiphytic and benthic bloom-former in tropical and subtropical shallow water systems but shares high phylogenetic similarity with the planktonic, globally important diazotroph Trichodesmium. Multiphasic observations in this study resulted in unexpected identification of Hydrocoleum sp. in mass accumulations in a coastal lagoon in the Western temperate North Atlantic Ocean. Hydrocoleum physiology was examined in situ through measurements of N₂ and CO₂ fixation rates and expression of genes involved with N₂ fixation, CO₂ fixation, and phosphorus (P) stress. Bulk N₂ fixation rates and Hydrocoleum nifH expression peaked at night and were strongly suppressed by dissolved inorganic nitrogen (DIN). The expression of high affinity phosphate transporter (pstS) and alkaline phosphatase (phoA) genes of Hydrocoleum was elevated during the night and negatively responded to phosphate amendments, as evidence that these mechanisms contribute to P acquisition during diazotrophic growth of Hydrocoleum in situ. This discovery at the edge of the previously known Hydrocoleum habitat range in the warming oceans raises intriguing questions about diazotrophic cyanobacterial adaptations and transitions on the benthic-pelagic continuum.

Use of physiologically‐based pharmacokinetic modeling to inform dosing of the opioid analgesics fentanyl and methadone in children with obesity

Obesity is an increasingly alarming public health threat, with nearly 20% of children classified as obese in the United States today. Children with obesity are commonly prescribed the opioids fentanyl and methadone, and accurate dosing is critical to reducing the risk of serious adverse events associated with overexposure. However, pharmacokinetic studies in children with obesity are challenging to conduct, so there is limited information to guide fentanyl and methadone dosing in these children. To address this clinical knowledge gap, physiologically‐based pharmacokinetic models of fentanyl and methadone were developed in adults and scaled to children with and without obesity to explore the interplay of obesity, age, and pharmacogenomics. These models included key obesity‐induced changes in physiology and pharmacogenomic effects. Model predictions captured observed concentrations in children with obesity well, with an overall average fold error of 0.72 and 1.08 for fentanyl and methadone, respectively. Model simulations support a reduced fentanyl dose (1 vs. 2 μg/kg/h) starting at an earlier age (6 years) in virtual children with obesity, highlighting the importance of considering both age and obesity status when selecting an infusion rate most likely to achieve steady‐state concentrations within the target range. Methadone dosing simulations highlight the importance of considering genotype in addition to obesity status when possible, as cytochrome P450 (CYP)2B6*6/*6 virtual children with obesity required half the dose to match the exposure of wildtype children without obesity. This physiologically‐based pharmacokinetic modeling approach can be applied to explore dosing of other critical drugs in children with obesity.

Biodegradation of hazardous naphthalene and cleaner production of rhamnolipids - Green approaches of pollution mitigation

Toxic and hazardous waste poses a serious threat to human health and the environment. Green remediation technologies are required to manage such waste materials, which is a demanding and difficult task. Here, effort was made to explore the role of Pseudomonas aeruginosa SR17 in alleviating naphthalene via catabolism and simultaneously producing biosurfactant. The results showed up to 89.2% naphthalene degradation at 35 °C and pH 7. The GC/MS analysis revealed the generation of naphthalene degradation intermediates. Biosurfactant production led to the reduction of surface tension of the culture medium to 34.5 mN/m. The biosurfactant was further characterized as rhamnolipids. LC-MS of the column purified biosurfactant revealed the presence of both mono and di rhamnolipid congeners. Rhamnolipid find tremendous application in medical field and as well as in detergent industry and since they are of biological origin, they can be used as favorable alternative against their chemical counterparts. The study demonstrated that catabolism of naphthalene and concurrent formation of rhamnolipid can result in a dual activity process, namely environmental cleanup and production of a valuable microbial metabolite. Additionally, the present-day application of rhamnolipids is highlighted.

Phytochemically stabilized chitosan encapsulated Cu and Ag nanocomposites to remove cefuroxime axetil and pathogens from the environment

Antibiotics have been a source of concern since they are causing resistance in bacteria that live in water and air. As a result, green technology was used to manufacture silver and copper nanoparticles, which were encapsulated with the biopolymer chitosan derived from the root extract of the Potentilla astrosanguinea plant. XRD, FTIR, TEM, EDX, and UV-Visible spectroscopy were methods used for structural and spectroscopic analysis. These nanomaterials have a roughly spherical 2-30 nm average size and a face-centered cubic (FCC) shape, according to the findings. The photocatalytic drug degradation and antibacterial properties of the produced nanocomposites were outstanding, with some resistance lasting longer than 180 days. The current study discovered that under UV light exposure, silver nanocomposites degrade drugs rapidly within 40 min, with an average rate of over 95%, while copper nanocomposites degrade drugs rapidly within 70 min, with an average rate of 84%. These nanocomposites have demonstrated exceptionally compelling antibacterial action against Gram-positive, Gram-negative, and fungal pathogens in addition to photocatalytic activity. The lowest recorded MIC values were 10.30 μg/mL and 10.84 μg/mL, respectively, whereas the lowest MBC values were 91.24 μg/mL and 99.50 μg/mL.

Contemporary Strategies to Promote Dialysis Access Fistula Maturation

Background: The inability of a newly created arteriovenous fistula to support hemodialysis due to non-maturation results in increased complications secondary to catheter dependence. Methods: In view of the highly variable approaches by providers with heterogenous backgrounds (general surgery, vascular surgery, interventional radiology and interventional nephrology, urology, transplant surgery, etc.) we sought to describe a collection of algorithms that have functioned well in our hands to manage this challenging clinical problem and guide trainees and practicing clinicians alike.Results: Physical examination along with selective duplex ultrasound and fistulogram can identify most pathologies underlying non-maturation.Conclusion: Both endovascular and open techniques can be employed to optimize maturation rates in this complex population.

CRISPR use in diagnosis and therapy for COVID-19

Since the beginning of the COVID-19 pandemic, many diagnostic approaches (RT-qPCR, RAPID, LFA) have been adopted, with RT-qPCR being the most popular/gold standard. But, one of the major problems of COVID-19 diagnostics is the presentation of a wide range of symptoms which varies among different patients and needs early diagnosis for better management. Even though RT-qPCR is a precise molecular technique false negative results may be obtained. On the other hand, CRISPR-based SARS-CoV-2 detection approaches are cost and time efficient, highly sensitive and specific, and do not require sophisticated instruments. Moreover, they also show promise for increased scalability and diagnostic tests can be carried out at the point-of-care (POC). The CRISPR can be customized to the target of any genomic region of interest within the desired genome possessing a broad range of other applications and has been efficiently implemented for diagnosis of SARS-CoV-2. The CRISPR/Cas systems provide the specific gene targeting with immense potential to develop new generation diagnostics and therapeutics. Moreover, with the CRISPR/Cas based therapeutics, multiplexing is possible, where different sgRNAs or crRNAs can be guided to more than one target within the same gene thus decreasing the possibility of viral escape mutants. As an exceptionally efficient tool CRISPR/Cas13 and CARVER (Cas13-assisted restriction of viral expression and readout) systems can be implemented to target a broad range of ssRNA viruses that can be used for both, diagnosis and treatment for a variety of viral diseases including SARS-CoV-2. However, the efficacy and safety of the CRISPR-based therapeutics needs to be assessed in pre-clinical and clinical settings. Although the CRISPR biotechnologies are not very helpful to control the present pandemic of COVID-19 it is hopeful that the limitations of the CRISPR/Cas system can be overcome in the near future. The CRISPR based strategies may lead to a new era in the field of disease diagnosis and therapeutic development that would make us better prepared for future viral threats.

Residual ctDNA after treatment predicts early relapse in patients with early-stage non-small cell lung cancer

BACKGROUND

Identification of residual disease in patients with localized non-small cell lung cancer (NSCLC) following treatment with curative intent holds promise to identify patients at risk of relapse. New methods can detect circulating tumour DNA (ctDNA) in plasma to fractional concentrations as low as a few parts per million, and clinical evidence is required to inform their use.

PATIENTS AND METHODS

We analyzed 363 serial plasma samples from 88 patients with early-stage NSCLC (48.9%/28.4%/22.7% at stage I/II/III), predominantly adenocarcinomas (62.5%), treated with curative intent by surgery (n = 61), surgery and adjuvant chemotherapy/radiotherapy (n = 8), or chemoradiotherapy (n = 19). Tumour exome sequencing identified somatic mutations and plasma was analyzed using patient-specific RaDaR™ assays with up to 48 amplicons targeting tumour-specific variants unique to each patient.

RESULTS

ctDNA was detected before treatment in 24%, 77% and 87% of patients with stage I, II and III disease, respectively, and in 26% of all longitudinal samples. The median tumour fraction detected was 0.042%, with 63% of samples <0.1% and 36% of samples <0.01%. ctDNA detection had clinical specificity >98.5% and preceded clinical detection of recurrence of the primary tumour by a median of 212.5 days. ctDNA was detected after treatment in 18/28 (64.3%) of patients who had clinical recurrence of their primary tumour. Detection within the landmark timepoint 2 weeks to 4 months after treatment end occurred in 17% of patients, and was associated with shorter recurrence-free survival [hazard ratio (HR): 14.8, P <0.00001] and overall survival (HR: 5.48, P <0.0003). ctDNA was detected 1-3 days after surgery in 25% of patients yet was not associated with disease recurrence. Detection before treatment was associated with shorter overall survival and recurrence-free survival (HR: 2.97 and 3.14, P values 0.01 and 0.003, respectively).

CONCLUSIONS

ctDNA detection after initial treatment of patients with early-stage NSCLC using sensitive patient-specific assays has potential to identify patients who may benefit from further therapeutic intervention.