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1.
Curr Drug Targets ; 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39385414

RESUMEN

The second largest cause of cancer-related death worldwide, Hepatocellular Carcinoma (HCC) is also the most common primary liver cancer. HCC typically arises in patients with liver cirrhosis. Existing synthetic medicines for treating chronic liver disease are ineffective and come with undesirable side effects. Although herbal remedies have widespread popularity, there is still a long road ahead before they are fully accepted by the scientific community. Secondary metabolites and phytochemicals found in plants are abundant in both the human diet and the non-human environment. Natural plant chemicals have been shown to be beneficial as therapeutic and chemopreventive treatments for a wide variety of chronic disorders. Many diseases, including HCC, can be effectively treated with the help of phytochemicals found in food. Resveratrol, curcumin, urolithin A, silibinin, quercetin, N-trans-feruloyl octopamine, emodin, lycopene, caffeine, and phloretin are all examples. Approximately, 60% of all anticancer medications are determined to be derived from natural substances, according to recent studies. Plant derivatives have played an important role in cancer due to their capacity to scavenge free radicals, limit cell proliferation, and set off apoptosis. The progression of HCC is linked to inflammatory signaling pathways, and this study sought to look at how novel approaches, such as phytomedicines, are being used to fight cancer. Recent advancements in molecular mechanisms and drug targeting for HCC have been discussed in this review.

2.
Artículo en Inglés | MEDLINE | ID: mdl-39390830

RESUMEN

There is a rapid spread of Multiple Sclerosis disorder across the globe, around 2.8 million cases of Multiple Sclerosis in the world. Multiple Sclerosis (MS) is a chronic autoimmune disease of the central nervous system characterized by demyelination, neuroinflammation, and a wide spectrum of clinical manifestations. Many drugs have been tested on MS patients but there is no effective treatment for MS till now. So to inhibit the symptoms caused by MS we performed a study in which we identified various naturally occurring materials with neuroprotective effects on the body that can treat Multiple Sclerosis. The therapeutic strategies portion of the paper reviews the array of disease-modifying therapies currently available for MS management. This paper evaluated their mechanisms of action, efficacy, and safety profiles. It also addressed emerging treatment paradigms by using different naturally occurring materials, including personalized medicine approaches and novel therapies in development. This paper provides a comprehensive overview of the current state of knowledge regarding MS, focusing on its pathogenesis, diagnostic approaches, and therapeutic strategies.

3.
Front Plant Sci ; 15: 1456414, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39363922

RESUMEN

Anthropogenic activities and subsequent global climate change instigate drastic crop productivity and yield changes. These changes comprise a rise in the number and severity of plant stress factors, which can arise simultaneously or sequentially. When abiotic stress factors are combined, their impact on plants is more substantial than that of a singleton stress factor. One such impact is the alteration of redox cellular homeostasis, which, in turn, can regulate downstream stress-responsive gene expression and resistance response. The epigenetic regulation of gene expression in response to varied stress factors is an interesting phenomenon, which, conversely, can be stable and heritable. The epigenetic control in plants in response to abiotic stress combinations and their interactions with cellular redox alteration is an emerging field to commemorate crop yield management under climate change. The article highlights the integration of the redox signaling pathways and epigenetic regulations as pivotal components in the complex network of plant responses against multi-combinatorial stresses across time and space. This review aims to lay the foundation for developing novel approaches to mitigate the impact of environmental stresses on crop productivity, bridging the gap between theoretical understanding and practical solutions in the face of a changing climate and anthropogenic disturbances.

4.
Int J Mol Sci ; 25(18)2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39337695

RESUMEN

Plant defence mechanisms, including physical barriers like toughened bark and chemical defences like allelochemicals, are essential for protecting them against pests. Trees allocate non-structural carbohydrates (NSCs) to produce secondary metabolites like monoterpenes, which increase during biotic stress to fend off pests like the Eurasian spruce bark beetle, ESBB (Ips typographus). Despite these defences, the ESBB infests Norway spruce, causing significant ecological damage by exploiting weakened trees and using pheromones for aggregation. However, the mechanism of sensing and resistance towards host allelochemicals in ESBB is poorly understood. We hypothesised that the exposure of ESBB to spruce allelochemicals, especially monoterpenes, leads to an upsurge in the important detoxification genes like P450s, GSTs, UGTs, and transporters, and at the same time, genes responsible for development must be compromised. The current study demonstrates that exposure to monoterpenes like R-limonene and sabiene effectively elevated detoxification enzyme activities. The differential gene expression (DGE) analysis revealed 294 differentially expressed (DE) detoxification genes in response to R-limonene and 426 DE detoxification genes in response to sabiene treatments, with 209 common genes between the treatments. Amongst these, genes from the cytochrome P450 family 4 and 6 genes (CP4 and CP6), esterases, glutathione S-transferases family 1 (GSTT1), UDP-glucuronosyltransferase 2B genes (UDB), and glucose synthesis-related dehydrogenases were highly upregulated. We further validated 19 genes using RT-qPCR. Additionally, we observed similar high expression levels of detoxification genes across different monoterpene treatments, including myrcene and α-pinene, suggesting a conserved detoxification mechanism in ESBB, which demands further investigation. These findings highlight the potential for molecular target-based beetle management strategies targeting these key detoxification genes.


Asunto(s)
Escarabajos , Inactivación Metabólica , Monoterpenos , Picea , Animales , Monoterpenos/metabolismo , Monoterpenos/farmacología , Picea/metabolismo , Picea/genética , Escarabajos/metabolismo , Escarabajos/genética , Escarabajos/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas , Sistema Enzimático del Citocromo P-450/metabolismo , Sistema Enzimático del Citocromo P-450/genética , Corteza de la Planta/química , Corteza de la Planta/metabolismo
5.
Int J Mol Sci ; 25(17)2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39273461

RESUMEN

The northern bark beetle, Ips duplicatus, is an emerging economic pest, reportedly infesting various species of spruce (Picea spp.), pine (Pinus spp.), and larch (Larix spp.) in Central Europe. Recent climate changes and inconsistent forest management practices have led to the rapid spread of this species, leaving the current monitoring strategies inefficient. As understanding the molecular components of pheromone detection is key to developing novel control strategies, we generated antennal transcriptomes from males and females of this species and annotated the chemosensory proteins. We identified putative candidates for 69 odorant receptors (ORs), 50 ionotropic receptors (IRs), 25 gustatory receptors (GRs), 27 odorant-binding proteins (OBPs), including a tetramer-OBP, 9 chemosensory proteins (CSPs), and 6 sensory neuron membrane proteins (SNMPs). However, no sex-specific chemosensory genes were detected. The phylogenetic analysis revealed conserved orthology in bark beetle chemosensory proteins, especially with a major forest pest and co-habitant, Ips typographus. Recent large-scale functional studies in I. typographus chemoreceptors add greater significance to the orthologous sequences reported here. Nevertheless, identifying chemosensory genes in I. duplicatus is valuable to understanding the chemosensory system and its evolution in bark beetles (Coleoptera) and, generally, insects.


Asunto(s)
Antenas de Artrópodos , Escarabajos , Proteínas de Insectos , Filogenia , Receptores Odorantes , Transcriptoma , Animales , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Masculino , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Femenino , Escarabajos/genética , Escarabajos/metabolismo , Antenas de Artrópodos/metabolismo , Perfilación de la Expresión Génica/métodos
6.
Int J Mol Sci ; 25(17)2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39273604

RESUMEN

The rhizosphere is the hotspot for microbial enzyme activities and contributes to carbon cycling. Precipitation is an important component of global climate change that can profoundly alter belowground microbial communities. However, the impact of precipitation on conifer rhizospheric microbial populations has not been investigated in detail. In the present study, using high-throughput amplicon sequencing, we investigated the impact of precipitation on the rhizospheric soil microbial communities in two Norway Spruce clonal seed orchards, Lipová Lhota (L-site) and Prenet (P-site). P-site has received nearly double the precipitation than L-site for the last three decades. P-site documented higher soil water content with a significantly higher abundance of Aluminium (Al), Iron (Fe), Phosphorous (P), and Sulphur (S) than L-site. Rhizospheric soil metabolite profiling revealed an increased abundance of acids, carbohydrates, fatty acids, and alcohols in P-site. There was variance in the relative abundance of distinct microbiomes between the sites. A higher abundance of Proteobacteria, Acidobacteriota, Ascomycota, and Mortiellomycota was observed in P-site receiving high precipitation, while Bacteroidota, Actinobacteria, Chloroflexi, Firmicutes, Gemmatimonadota, and Basidiomycota were prevalent in L-site. The higher clustering coefficient of the microbial network in P-site suggested that the microbial community structure is highly interconnected and tends to cluster closely. The current study unveils the impact of precipitation variations on the spruce rhizospheric microbial association and opens new avenues for understanding the impact of global change on conifer rizospheric microbial associations.


Asunto(s)
Microbiota , Picea , Rizosfera , Microbiología del Suelo , Picea/microbiología , Microbiota/genética , Bacterias/genética , Bacterias/clasificación , Bacterias/metabolismo , Suelo/química , Lluvia , Semillas/crecimiento & desarrollo , Semillas/microbiología , Cambio Climático
7.
Biochimie ; 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39128491

RESUMEN

Unicellular protozoan parasite Leishmania donovani is the causative agent for visceral leishmaniasis (VL) or Kala-azar, a neglected fatal parasitic disease. The conventional treatment of VL consists of therapeutic agents having several shortcomings such as toxicity, high cost, efficacy variance and increased drug resistance. Therefore, there is a desperate need to develop an effective treatment against the parasite. Previous reports suggested that flavonoids can inhibit the enzyme Leishmania donovani DNA topoisomerase I (LdTopILS). Therefore, for the first time in this present study, we divulge HSP (one of the natural sources of flavonoids), as a potent natural antileishmanial compound with efficacy in BALB/c mice at 20 mg/kg of body weight, inhibits LdTopILS at 97 % of its activity at 160 µM in preincubation condition (competitively). It binds with free enzyme and does not allow it to bind with the substrate DNA. Moreover, HSP does not stabilize DNA-topoisomerase I cleavable complex. Thus, HSP acts a catalytic topoisomerase I inhibitor, which inhibits complete activity by binding with Lys269 and Thr411 of large subunit of the enzyme. On the other hand, HSP induces the topo I-mediated programmed cell death process by the formation of cellular reactive oxygen species, resulting in depolarization of mitochondrial membrane potential, followed by fragmentation of nuclear DNA. Therefore, the present study illuminates a natural flavonoid that in future might be a promising lead for the treatment of VL.

8.
Artículo en Inglés | MEDLINE | ID: mdl-39154319

RESUMEN

Visual predictive checks (VPC) are commonly used to evaluate pharmacometrics models. However their performance may be hampered if patients with worse outcomes drop out earlier, as often occurs in clinical trials, especially in oncology. While methods accounting for dropouts have appeared in literature, they vary in assumptions, flexibility, and performance, and the differences between them are not widely understood. This manuscript aims to elucidate which methods can be used to handle VPC with dropout and when, along with a more informative VPC approach using confidence intervals. Additionally, we propose constructing the confidence interval based on the observed data instead of the simulated data. The theoretical framework for incorporating dropout in VPCs is developed and applied to propose two approaches: full and conditional. The full approach is implemented using a parametric time-to-event model, while the conditional approach is implemented using both parametric and Cox proportional-hazard (CPH) models. The practical performances of these approaches are illustrated with an application to the tumor growth dynamics (TGD) modeling of data from two cancer clinical trials of nivolumab and docetaxel, where patients were followed until disease progression. The dataset consisted of 3504 tumor size measurements from 855 subjects, which were described by a TGD model. The dropout of subjects was described by a Weibull or CPH model. Simulated datasets were also used to further illustrate the properties of the VPC methods. The results showed that the more familiar full approach might not provide meaningful improvement for TGD model evaluation over the naive approach of not adjusting for dropout, and could be outperformed by the conditional approach using either the Weibull model or the Cox proportional hazard model. Overall, including confidence intervals in VPC should improve interpretation, the conditional approach was shown to be more generally applicable when dropout occurs, and the nonparametric approach could provide additional robustness.

9.
Artículo en Inglés | MEDLINE | ID: mdl-39136278

RESUMEN

Mavacamten is a selective, allosteric, reversible cardiac myosin inhibitor that has been developed for the treatment of adults with symptomatic obstructive hypertrophic cardiomyopathy (HCM). A population pharmacokinetic (PopPK) model was developed to characterize mavacamten pharmacokinetics (PK) and the variation in mavacamten exposure associated with intrinsic and extrinsic factors. Data from 12 clinical studies (phases 1, 2, and 3) were used. Evaluable participants were those who had at least one mavacamten concentration measurement with associated sampling time and dosing information. The base model included key covariates: body weight, cytochrome P450 isozyme 2C19 (CYP2C19) phenotype with respect to PK, and formulation. The final model was generated using stepwise covariate testing and refinement processes. Simulations were performed to evaluate PK: apparent clearance (CL/F); apparent central and peripheral volumes of distribution; and steady-state average, trough, and maximum concentrations. Overall, 9244 measurable PK observations from 497 participants were included. A two-compartment model structure was selected. After stepwise covariate model building and refinement, additional covariates included were: specified mavacamten dose, omeprazole or esomeprazole administration, health/disease status, estimated glomerular filtration rate, fed status, and sex. The final PopPK model accurately characterized mavacamten concentrations. At any given dose, CYP2C19 phenotype was the most influential covariate on exposure parameters (e.g., median CL/F was reduced by 72% in CYP2C19:poor metabolizers compared with the reference participant [CYP2C19:normal metabolizer]). CL/F was also approximately 16% higher in women than in men but lower in participants receiving concomitant omeprazole or esomeprazole (by 33% and 42%, respectively) than in participants not receiving such concomitant therapy.

10.
Br J Clin Pharmacol ; 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39054780

RESUMEN

AIMS: Nivolumab is approved as adjuvant treatment in subjects with resected oesophageal or gastroesophageal junction cancer (EC/GEJC) based on results from the pivotal CheckMate 577 trial. We present a model-based clinical pharmacology profiling and benefit-risk assessment of nivolumab as adjuvant treatment in subjects with resected EC/GEJC supporting a less frequent dosing regimen. METHODS: Population pharmacokinetic (popPK) analysis was conducted to characterize nivolumab pharmacokinetics (PK) using clinical data from 1493 subjects from seven monotherapy clinical studies across multiple solid tumours. The exposure-response (E-R) analyses included data from 756 patients from CheckMate 577. E-R relationships for efficacy and safety were characterized by evaluating the relationship between nivolumab exposure and disease-free survival (DFS) for efficacy; and time to first occurrence of Grade ≥2 immune-mediated adverse events (Gr2 + IMAEs) for safety. RESULTS: Nivolumab exposure was found to be associated with both DFS and risk of Gr2 + IMAEs. However, the hazard ratios (HRs) (95% confidence interval [CI]) at the 5th and 95th percentiles of nivolumab exposure were similar for DFS and Gr2 + IMAEs, indicating flat E-R relationships within the exposure range produced by the studied regimen. Model-predicted probability of DFS and Gr2 + IMAEs were similar between the two regimens of 240 mg every 2 weeks or 480 mg every 4 weeks for 16 weeks followed by 480 mg Q4W up to 1 year. CONCLUSIONS: The analyses demonstrated a flat E-R relationship over the range of exposures produced by the studied regimen and supported the approval of an alternative dosing regimen with less frequent dosing in patients with adjuvant EC/GEJC.

11.
J Assoc Physicians India ; 72(6): 15-19, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38881128

RESUMEN

BACKGROUND: The modified Ponticelli regimen (mPR) is a first-line therapy in patients with idiopathic membranous nephropathy (IMN); however, it has a less favorable safety profile. Though mycophenolate mofetil (MMF) + steroid (S) is not recommended by Kidney Disease Improving Global Outcomes guidelines, it can be used as an alternative to mPR due to higher tolerability and steroid-sparing effect. Thus, we compared the safety and effectiveness of MMF + S and mPR regimens in patients with IMN. METHODS: This randomized, open-label study enrolled patients with adult-onset nephrotic syndrome (NS) and biopsy-proven IMN. Forty-two patients were allocated to MMF + S group (MMF 1 gm twice daily + oral prednisolone 0.5 mg/kg/day; n = 21) and mPR group [methylprednisolone (1 gm intravenous) for 3 days followed by alternating monthly cycles of oral prednisolone (0.5 mg/kg/day) for the next 27 days and cyclophosphamide (2 mg/kg/day) for 6 months; n = 21]. The primary outcome measure was change in urinary protein creatinine ratio (UPCR). RESULTS: At 6 months, both groups demonstrated a significant increase in serum albumin levels and estimated glomerular filtration rate (eGFR) (both p-values <0.0001) as well as a decrease in 24-hour proteinuria (MMF + S group: p-value = 0.003, and mPR group: p-value <0.0001) and UPCR (both p-values <0.0001). However, the groups did not differ in any of these parameters at any of the monthly follow-up visits. Moreover, the groups did not differ significantly in terms of the composite remission rates (61.91% for MMF + S group and 71.43% for mPR group). CONCLUSION: MMF + S and mPR had comparable tolerability and effectiveness, with MMF-associated advantage of reduced steroid exposure.


Asunto(s)
Quimioterapia Combinada , Glomerulonefritis Membranosa , Inmunosupresores , Ácido Micofenólico , Prednisolona , Humanos , Glomerulonefritis Membranosa/tratamiento farmacológico , Ácido Micofenólico/uso terapéutico , Ácido Micofenólico/administración & dosificación , Masculino , Femenino , Adulto , Inmunosupresores/administración & dosificación , Inmunosupresores/uso terapéutico , Prednisolona/administración & dosificación , Prednisolona/uso terapéutico , Persona de Mediana Edad , Glucocorticoides/administración & dosificación , Glucocorticoides/uso terapéutico , Ciclofosfamida/uso terapéutico , Ciclofosfamida/administración & dosificación , Metilprednisolona/administración & dosificación , Metilprednisolona/uso terapéutico , Resultado del Tratamiento
12.
Int J Mol Sci ; 25(11)2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38892311

RESUMEN

Plants and insects coevolved as an evolutionarily successful and enduring association. The molecular arms race led to evolutionary novelties regarding unique mechanisms of defence and detoxification in plants and insects. While insects adopt mechanisms to conquer host defence, trees develop well-orchestrated and species-specific defence strategies against insect herbivory. However, current knowledge on the molecular underpinnings of fine-tuned tree defence responses against different herbivore insects is still restricted. In the current study, using a multi-omics approach, we unveiled the defence response of Populus tremula against aphids (Chaitophorus populialbae) and spongy moths (Lymantria dispar) herbivory. Comparative differential gene expression (DGE) analyses revealed that around 272 and 1203 transcripts were differentially regulated in P. tremula after moth and aphid herbivory compared to uninfested controls. Interestingly, 5716 transcripts were differentially regulated in P. tremula between aphids and moth infestation. Further investigation showed that defence-related stress hormones and their lipid precursors, transcription factors, and signalling molecules were over-expressed, whereas the growth-related counterparts were suppressed in P. tremula after aphid and moth herbivory. Metabolomics analysis documented that around 37% of all significantly abundant metabolites were associated with biochemical pathways related to tree growth and defence. However, the metabolic profiles of aphid and moth-fed trees were quite distinct, indicating species-specific response optimization. After identifying the suitable reference genes in P. tremula, the omics data were further validated using RT-qPCR. Nevertheless, our findings documented species-specific fine-tuning of the defence response of P. tremula, showing conservation on resource allocation for defence overgrowth under aphid and moth herbivory. Such findings can be exploited to enhance our current understanding of molecular orchestration of tree responses against herbivory and aid in developing insect pest resistance P. tremula varieties.


Asunto(s)
Áfidos , Regulación de la Expresión Génica de las Plantas , Herbivoria , Mariposas Nocturnas , Populus , Transcriptoma , Populus/genética , Populus/parasitología , Populus/metabolismo , Animales , Áfidos/fisiología , Mariposas Nocturnas/fisiología , Mariposas Nocturnas/genética , Metabolómica/métodos , Perfilación de la Expresión Génica , Metaboloma
13.
Sci Rep ; 14(1): 10792, 2024 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-38734752

RESUMEN

Epilepsy is a chronic neurological disease, characterized by spontaneous, unprovoked, recurrent seizures that may lead to long-term disability and premature death. Despite significant efforts made to improve epilepsy detection clinically and pre-clinically, the pervasive presence of noise in EEG signals continues to pose substantial challenges to their effective application. In addition, discriminant features for epilepsy detection have not been investigated yet. The objective of this study is to develop a hybrid model for epilepsy detection from noisy and fragmented EEG signals. We hypothesized that a hybrid model could surpass existing single models in epilepsy detection. Our approach involves manual noise rejection and a novel statistical channel selection technique to detect epilepsy even from noisy EEG signals. Our proposed Base-2-Meta stacking classifier achieved notable accuracy (0.98 ± 0.05), precision (0.98 ± 0.07), recall (0.98 ± 0.05), and F1 score (0.98 ± 0.04) even with noisy 5-s segmented EEG signals. Application of our approach to the specific problem like detection of epilepsy from noisy and fragmented EEG data reveals a performance that is not only superior to others, but also is translationally relevant, highlighting its potential application in a clinic setting, where EEG signals are often noisy or scanty. Our proposed metric DF-A (Discriminant feature-accuracy), for the first time, identified the most discriminant feature with models that give A accuracy or above (A = 95 used in this study). This groundbreaking approach allows for detecting discriminant features and can be used as potential electrographic biomarkers in epilepsy detection research. Moreover, our study introduces innovative insights into the understanding of these features, epilepsy detection, and cross-validation, markedly improving epilepsy detection in ways previously unavailable.


Asunto(s)
Electroencefalografía , Epilepsia , Electroencefalografía/métodos , Humanos , Epilepsia/diagnóstico , Epilepsia/fisiopatología , Procesamiento de Señales Asistido por Computador , Algoritmos , Relación Señal-Ruido
14.
Artículo en Inglés | MEDLINE | ID: mdl-38695527

RESUMEN

Mavacamten is the first cardiac myosin inhibitor approved by the US Food and Drug Administration for the treatment of adults with symptomatic obstructive hypertrophic cardiomyopathy (HCM). The phase III EXPLORER-HCM (NCT03470545) study used a dose-titration scheme based on mavacamten exposure and echocardiographic assessment of Valsalva left ventricular outflow tract gradient (VLVOTg) and left ventricular ejection fraction (LVEF). Using population pharmacokinetic/exposure-response modeling and simulations of virtual patients, this in silico study evaluated alternative dose-titration regimens for mavacamten, including regimens that were guided by echocardiographic measures only. Mavacamten exposure-response models for VLVOTg (efficacy) and LVEF (safety) were developed using patient data from five clinical studies and characterized using nonlinear mixed-effects models. Simulations of five echocardiography-guided regimens were performed in virtual cohorts constructed based on either expected or equal population distributions of cytochrome P450 2C19 (CYP2C19) metabolizer phenotypes. Each regimen aimed to maximize the proportions of patients who achieved a VLVOTg below 30 mm Hg while maintaining LVEF above 50% over 40 weeks and 104 weeks, respectively. The exposure-response models successfully characterized mavacamten efficacy and safety parameters. Overall, the simulated regimen with the optimal benefit-risk profile across CYP2C19 phenotypes had steps for down-titration at weeks 4 and 8 (for VLVOTg <20 mm Hg), and up-titration at week 12 (for VLVOTg ≥30 mm Hg and LVEF ≥55%), and every 12 weeks thereafter. This simulation-optimized regimen is recommended in the mavacamten US prescribing information.

16.
Sci Total Environ ; 926: 171286, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38428617

RESUMEN

Vacuolar-type (H+)-ATPase (vATPase) is a conserved multi-subunit eukaryotic enzyme composed of 14 subunits that form a functional complex consisting of an ATP-hydrolytic domain (V1) and a proton-translocation domain (V0). ATP hydrolysis and subsequent H+ translocation rely heavily on a fully assembled V1/V0 complex. Since vATPase is crucial for insect survival, it is a viable molecular target for pest control. However, detailed functional analyses of the 14 subunits and their suitability for pest control have not been fully explored in a single insect species. In this study, we identified 22 vATPase subunit transcripts that correspond to 13 subunits (A1, A2, B, C, D, E, F, G, H, a1, a2, c and d) in the white-backed planthopper (WBPH), Sogatella furcifera, a major hemipteran pest of rice. RNAi screens using microinjection and spray-based methods revealed that the SfVHA-F, SfVHA-a2 and SfVHA-c2 subunits are critical. Furthermore, star polymer (SPc) nanoparticles were utilized to conduct spray-induced and nanoparticle-delivered gene silencing (SI-NDGS) to evaluate the pest control efficacy of RNAi targeting the SfVHA-F, SfVHA-a2 and SfVHA-c2 transcripts. Target mRNA levels and vATPase enzymatic activity were both reduced. Honeydew excreta was likewise reduced in WBPH treated with dsRNAs targeting SfVHA-F, SfVHA-a2 and SfVHA-c2. To assess the environmental safety of the nanoparticle-wrapped dsRNAs, Cyrtorhinus lividipennis Reuter, a major natural enemy of planthoppers, was also sprayed with dsRNAs targeting SfVHA-F, SfVHA-a2 and SfVHA-c2. Post-spray effects of dsSfVHA-a2 and dsSfVHA-c2 on C. lividipennis were innocuous. This study identifies SfVHA-a2 and SfVHA-c2 as promising targets for biorational control of WBPH and lays the foundation for developing environment-friendly RNAi biopesticides.


Asunto(s)
Hemípteros , Heterópteros , Oryza , Plaguicidas , Animales , Oryza/genética , Interferencia de ARN , Medición de Riesgo , Adenosina Trifosfato
17.
Clin Cancer Res ; 30(14): 3050-3058, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38295151

RESUMEN

PURPOSE: Progression-free survival (PFS) was significantly improved with nivolumab 480 mg plus relatlimab 160 mg fixed-dose combination (FDC) every 4 weeks (Q4W) versus nivolumab alone in patients with previously untreated advanced melanoma in RELATIVITY-047. In addition, RELATIVITY-020 (Part D) demonstrated a manageable safety profile and potential for durable response with nivolumab plus relatlimab in previously treated patients. Here, we evaluate the clinical pharmacology profile (CPP) of nivolumab plus relatlimab to support the approved regimen for adult and adolescent patients with advanced melanoma and its continued clinical development in solid tumors. EXPERIMENTAL DESIGN: The pharmacokinetics (PK) and immunogenicity of relatlimab and nivolumab were assessed using data from RELATIVITY-047 and RELATIVITY-020. Patients with advanced solid tumors received relatlimab alone or nivolumab plus relatlimab as single-agent vials (SAV) or FDC. PK was characterized using a population PK (popPK) model. RESULTS: Relatlimab demonstrated nonlinear and time-varying PK. Nonlinearity in relatlimab PK represented approximately 31% of total CL of relatlimab 160 mg Q4W. Relatlimab PK was dose proportional at doses ≥160 mg Q4W. Geometric mean exposures were similar for SAV and FDC cohorts receiving equivalent dosing regimens. No dose adjustment was required for covariates. Incidence of relatlimab antidrug antibodies was <6% for nivolumab plus relatlimab and had no clinically meaningful impact. There was no PK-related drug interaction of nivolumab plus relatlimab. CONCLUSIONS: The CPP of relatlimab alone or in combination with nivolumab supports the approved dosing in advanced melanoma and the continued evaluation of nivolumab and relatlimab across other solid tumors. See related commentary by Gopalakrishnan and Amaria, p. 2862.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias , Nivolumab , Humanos , Nivolumab/administración & dosificación , Nivolumab/farmacología , Nivolumab/farmacocinética , Adolescente , Femenino , Adulto , Masculino , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Persona de Mediana Edad , Adulto Joven , Anciano , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/farmacocinética , Melanoma/tratamiento farmacológico , Melanoma/patología
18.
Clin Pharmacol Ther ; 115(3): 412-421, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38069528

RESUMEN

The transition from intravenous (i.v.) to subcutaneous (s.c.) administration of biologics is a critical strategy in drug development aimed at improving patient convenience, compliance, and therapeutic outcomes. Focusing on the increasing role of model-informed drug development (MIDD) in the acceleration of this transition, an in-depth overview of the essential clinical pharmacology, and regulatory considerations for successful i.v. to s.c. bridging for biologics after the i.v. formulation has been approved are presented. Considerations encompass multiple aspects beginning with adequate pharmacokinetic (PK) and pharmacodynamic (i.e., exposure-response) evaluations which play a vital role in establishing comparability between the i.v. and s.c. routes of administrations. Selected key recommendations and points to consider include: (i) PK characterization of the s.c. formulation, supported by the increasing preclinical understanding of the s.c. absorption, and robust PK study design and analyses in humans; (ii) a thorough characterization of the exposure-response profiles including important metrics of exposure for both efficacy and safety; (iii) comparability studies designed to meet regulatory considerations and support approval of the s.c. formulation, including noninferiority studies with PK and/or efficacy and safety as primary end points; and (iv) comprehensive safety package addressing assessments of immunogenicity and patients' safety profile with the new route of administration. Recommendations for successful bridging strategies are evolving and MIDD approaches have been used successfully to accelerate the transition to s.c. dosing, ultimately leading to improved patient experiences, adherence, and clinical outcomes.


Asunto(s)
Productos Biológicos , Humanos , Administración Intravenosa
19.
CPT Pharmacometrics Syst Pharmacol ; 13(1): 168-179, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37873561

RESUMEN

An exposure-response (E-R) safety analysis was conducted across adult and pediatric (<18 years) studies to evaluate the potential impact of higher nivolumab and/or ipilimumab exposures in adolescents (≥12 to <18 years) versus adults with melanoma using the approved adult dosing regimens for nivolumab alone or in combination with ipilimumab. Data from 3507 patients across 15 studies were used to examine the relationship between nivolumab-ipilimumab daily average exposure and time to grade 2+ immune-mediated adverse events (gr2+ IMAEs). Results from the E-R safety model showed ipilimumab, but not nivolumab, exposure to be a statistically significant predictor of gr2+ IMAEs. Significant covariates included sex (41% higher risk for women than men), line of therapy (19% higher for first-line than later-line), and treatment setting (26% lower for adjuvant than advanced melanoma). Younger age and lower body weight (BW) were each associated with a lower risk of gr2+ IMAEs (hazard ratio [HR]: 0.830 for 15-year-olds versus 60-year-olds and 0.84 for BW 52 kg versus 75 kg). For adolescents with melanoma treated with nivolumab in the advanced or adjuvant settings, these results are supportive of nivolumab flat dosing regimens for adolescents greater than or equal to 40 kg and BW-based dosing for adolescents less than 40 kg. These results also support adult weight-based dosing regimens for nivolumab plus ipilimumab in adolescents with advanced melanoma. This analysis suggests that although higher exposures are predicted in adolescents with lower weight compared with adults, there is no predicted immune-mediated safety risk when treated with the approved adult dosing of nivolumab with/without ipilimumab.


Asunto(s)
Melanoma , Adulto , Masculino , Adolescente , Humanos , Femenino , Niño , Melanoma/tratamiento farmacológico , Melanoma/patología , Nivolumab , Ipilimumab/efectos adversos , Anticuerpos Monoclonales , Estadificación de Neoplasias , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos
20.
Insect Biochem Mol Biol ; 165: 104061, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38151136

RESUMEN

Host shift is ecologically advantageous and a crucial driver for herbivore insect speciation. Insects on the non-native host obtain enemy-free space and confront reduced competition, but they must adapt to survive. Such signatures of adaptations can often be detected at the gene expression level. It is astonishing how bark beetles cope with distinct chemical environments while feeding on various conifers. Hence, we aim to disentangle the six-toothed bark beetle (Ips sexdentatus) response against two different conifer defences upon host shift (Scots pine to Norway spruce). We conducted bioassay and metabolomic analysis followed by RNA-seq experiments to comprehend the beetle's ability to surpass two different terpene-based conifer defence systems. Beetle growth rate and fecundity were increased when reared exclusively on spruce logs (alternative host) compared to pine logs (native host). Comparative gene expression analysis identified differentially expressed genes (DEGs) related to digestion, detoxification, transporter activity, growth, signalling, and stress response in the spruce-feeding beetle gut. Transporter genes were highly abundant during spruce feeding, suggesting they could play a role in pumping a wide variety of endogenous and xenobiotic compounds or allelochemicals out. Trehalose transporter (TRET) is also up-regulated in the spruce-fed beetle gut to maintain homeostasis and stress tolerance. RT-qPCR and enzymatic assays further corroborated some of our findings. Taken together, the transcriptional plasticity of key physiological genes plays a crucial role after the host shift and provides vital clues for the adaptive potential of bark beetles on different conifer hosts.


Asunto(s)
Escarabajos , Gorgojos , Animales , Escarabajos/metabolismo , Gorgojos/metabolismo , Perfilación de la Expresión Génica , Terpenos/metabolismo , Expresión Génica
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