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1.
Redox Biol ; 75: 103285, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39128229

RESUMEN

The ability of Mycobacterium tuberculosis (Mtb) to tolerate nitric oxide (•NO) and superoxide (O2•-) produced by phagocytes contributes to its success as a human pathogen. Recombination of •NO and O2•- generates peroxynitrite (ONOO-), a potent oxidant produced inside activated macrophages causing lethality in diverse organisms. While the response of Mtb toward •NO and O2•- is well established, how Mtb responds to ONOO- remains unclear. Filling this knowledge gap is important to understand the persistence mechanisms of Mtb during infection. We synthesized a series of compounds that generate both •NO and O2•-, which should combine to produce ONOO-. From this library, we identified CJ067 that permeates Mtb to reliably enhance intracellular ONOO- levels. CJ067-exposed Mtb strains, including multidrug-resistant (MDR) and extensively drug-resistant (XDR) clinical isolates, exhibited dose-dependent, long-lasting oxidative stress and growth inhibition. In contrast, Mycobacterium smegmatis (Msm), a fast-growing, non-pathogenic mycobacterial species, maintained redox balance and growth in response to intracellular ONOO-. RNA-sequencing with Mtb revealed that CJ067 induces antioxidant machinery, sulphur metabolism, metal homeostasis, and a 4Fe-4S cluster repair pathway (suf operon). CJ067 impaired the activity of the 4Fe-4S cluster-containing TCA cycle enzyme, aconitase, and diminished bioenergetics of Mtb. Work with Mtb strains defective in SUF and IscS involved in Fe-S cluster biogenesis pathways showed that both systems cooperatively protect Mtb from intracellular ONOO- in vitro and inducible nitric oxide synthase (iNOS)-dependent growth inhibition during macrophage infection. Thus, Mtb is uniquely sensitive to intracellular ONOO- and targeting Fe-S cluster homeostasis is expected to promote iNOS-dependent host immunity against tuberculosis (TB).


Asunto(s)
Metabolismo Energético , Homeostasis , Proteínas Hierro-Azufre , Mycobacterium tuberculosis , Oxidación-Reducción , Ácido Peroxinitroso , Mycobacterium tuberculosis/metabolismo , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/efectos de los fármacos , Ácido Peroxinitroso/metabolismo , Proteínas Hierro-Azufre/metabolismo , Proteínas Hierro-Azufre/genética , Humanos , Óxido Nítrico/metabolismo , Estrés Oxidativo , Mycobacterium smegmatis/metabolismo , Mycobacterium smegmatis/genética , Mycobacterium smegmatis/efectos de los fármacos , Superóxidos/metabolismo , Macrófagos/metabolismo , Macrófagos/microbiología , Tuberculosis/microbiología , Tuberculosis/metabolismo
2.
Biochem Biophys Rep ; 39: 101793, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39161580

RESUMEN

Plasminogen activator inhibitor-1 (PAI-1/Serpin E1) is classically known for its antifibrinolytic activity via inhibiting uPA and tPA of the fibrinolytic pathway. PAI-1 has a paradoxical role in tumor progression, and its molecular functions are poorly understood. PAI-1 is a widely accepted secretory protease inhibitor, however, a study suggested the localization of PAI-1 in the cytoplasm and the nucleus. Besides the plethora of its biological functions as a secretory protein, intracellular localization, and functions of PAI-1 remain unexplored at the molecular level. In this study, using various in silico approaches, we showed that PAI-1 possesses a nuclear export signal. Using the CRM1-specific inhibitor leptomycin B, we demonstrated that PAI-1 has a functional CRM1-dependent NES, indicating the possibility of its nuclear localization. Further, we confirm that PAI-1 is localized in the nucleus of endothelial cells using fluorescence microscopy and immunoprecipitation. Notably, we identified an unconventional distribution of PAI-1 in the PML bodies of the nucleus of normal endothelial cells, while the protein was restricted in the cytoplasm of slow-growing cells. The data showed that the localization of PAI-1 in PML bodies is highly correlated with the growth potential of endothelial cells. This conditional nucleocytoplasmic shuttling of PAI-1 during the aging of cells could impart a strong link to its age-related functions and tumor progression. Together, this study identifies the novel behavior of PAI-1 that might be linked with cell aging and may be able to unveil the elusive role of PAI-1 in tumor progression.

3.
Environ Pollut ; 352: 124122, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38723707

RESUMEN

In viticulture, the use of synthetic chemical formulations introduces insecticide residues into harvested grapes and further into processed grape products, posing a safety concern to consumers. This study investigated the fate of ten insecticide residues and their metabolites from vine to wine. A rapid validated multi-residue approach using QuEChERS extraction and LC-MS/MS configuration was employed for targeted analysis in grape, pomace, and wine. The targeted insecticides showed satisfactory mean recoveries (76.03-111.95%) and precision (RSD = 0.75-7.90%) across the three matrices, with a matrix effect ranging from -16.88 to 35.18%, particularly higher in pomace. Preliminary grape washing effectively removed 15.52-61.31% of insecticide residues based on water solubility and systemic nature. Residue dissipation during fermentation ranged from 73.19% to 87.15% with a half-life spanning from 1 to 5.5 days. The mitigation rate was observed at 12.85-26.81% for wine and 17.76-51.55% for pomace, with the highest transfer rate for buprofezin (51.55%) to pomace and fipronil (25.72%) to wine. Calculated processing factors (PF) for final wine ranged from 0.16 to 0.44, correlating strongly with the octanol-water partition ratio of targeted insecticides. The reported PF, calculated hazard quotient (HQ) (0.003-5.800%), and chronic hazard index (cHI) (2.041-10.387%) indicate reduced residue concentrations in wine and no potential chronic risk to consumers, ensuring a lower dietary risk to wine consumers.


Asunto(s)
Insecticidas , Residuos de Plaguicidas , Vitis , Vino , Insecticidas/análisis , Residuos de Plaguicidas/análisis , Vitis/química , Medición de Riesgo/métodos , Vino/análisis , Cinética , Espectrometría de Masas en Tándem/métodos , Contaminación de Alimentos/análisis , Cromatografía Liquida/métodos
4.
J Vis Exp ; (206)2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38738900

RESUMEN

Bacterial cytoskeletal proteins such as FtsZ and MreB perform essential functions such as cell division and cell shape maintenance. Further, FtsZ and MreB have emerged as important targets for novel antimicrobial discovery. Several assays have been developed to identify compounds targeting nucleotide binding and polymerization of these cytoskeletal proteins, primarily focused on FtsZ. Moreover, many of the assays are either laborious or cost-intensive, and ascertaining whether these proteins are the cellular target of the drug often requires multiple methods. Finally, the toxicity of the drugs to eukaryotic cells also poses a problem. Here, we describe a single-step cell-based assay to discover novel molecules targeting bacterial cytoskeleton and minimize hits that might be potentially toxic to eukaryotic cells. Fission yeast is amenable to high-throughput screens based on microscopy, and a visual screen can easily identify any molecule that alters the polymerization of FtsZ or MreB. Our assay utilizes the standard 96-well plate and relies on the ability of the bacterial cytoskeletal proteins to polymerize in a eukaryotic cell such as the fission yeast. While the protocols described here are for fission yeast and utilize FtsZ from Staphylococcus aureus and MreB from Escherichia coli, they are easily adaptable to other bacterial cytoskeletal proteins that readily assemble into polymers in any eukaryotic expression hosts. The method described here should help facilitate further discovery of novel antimicrobials targeting bacterial cytoskeletal proteins.


Asunto(s)
Antibacterianos , Proteínas Bacterianas , Proteínas del Citoesqueleto , Schizosaccharomyces , Schizosaccharomyces/efectos de los fármacos , Schizosaccharomyces/metabolismo , Proteínas del Citoesqueleto/metabolismo , Proteínas del Citoesqueleto/antagonistas & inhibidores , Antibacterianos/farmacología , Antibacterianos/química , Proteínas Bacterianas/metabolismo , Evaluación Preclínica de Medicamentos/métodos
5.
Int J Radiat Biol ; 100(5): 689-708, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38306495

RESUMEN

PURPOSE: This research endeavor was undertaken to elucidate the impact of an innovative ascorbate formulation on the regeneration process of full-thickness excision wounds in a rat model exposed to whole-body gamma irradiation, replicating conditions akin to combat or radiation emergency scenarios. MATERIALS AND METHODS: We established a comprehensive rat model by optimizing whole body γ-radiation doses (5-9 Gy) and full-thickness excision wound sizes (1-3 cm2) to mimic radiation combined injury (RCI). The developed RCI model was used to explore the healing potential of ascorbate formulation. The study includes various treatment groups (i.e., sham control, radiation alone, wound alone, radiation + wound, and radiation + wound + formulation). The ascorbate formulation was applied twice daily, with a 12-hour gap between each application, starting 1 hour after the initiation of the wound. The healing potential of the formulation in the RCI context was evaluated over 14 days through hematological, molecular, and histological parameters. RESULTS: The combination of a 5 Gy radiation dose and a 1 cm2 wound was identified as the optimal setting to develop the RCI model for subsequent studies. The formulation was used topically immediately following RCI, and then twice daily until complete healing. Treatment with the ascorbate formulation yielded noteworthy outcomes and led to a substantial reduction (p < .05) in the wound area, accelerated epithelialization periods, and an increased wound contraction rate. The formulation's localized healing response improved organ weights, normalized blood parameters, and enhanced hematopoietic and immune systems. A gene expression study revealed the treatment up-regulated TGF-ß and FGF, and down-regulated PDGF-α, TNF-α, IL-1ß, IL-6, MIP-1α, and MCP-1 (p < .05). Histopathological assessments supported the formulation's effectiveness in restoring cellular architecture and promoting tissue regeneration. CONCLUSION: Topical application of the ascorbate formulation in RCI resulted in a significant improvement in delayed wound healing, leading to accelerated wound closure by mitigating the expression of inflammatory responses.


Asunto(s)
Administración Tópica , Ácido Ascórbico , Piel , Cicatrización de Heridas , Animales , Ácido Ascórbico/farmacología , Ácido Ascórbico/administración & dosificación , Ratas , Cicatrización de Heridas/efectos de los fármacos , Cicatrización de Heridas/efectos de la radiación , Piel/efectos de la radiación , Piel/efectos de los fármacos , Piel/lesiones , Piel/patología , Masculino , Modelos Animales de Enfermedad , Traumatismos Experimentales por Radiación/tratamiento farmacológico , Traumatismos Experimentales por Radiación/patología , Ratas Sprague-Dawley , Rayos gamma , Irradiación Corporal Total
6.
Adv Sci (Weinh) ; 11(16): e2308617, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38421139

RESUMEN

The limited availability of molecularly targeted low-molecular-weight imaging agents for monitoring multiple myeloma (MM)-targeted therapies has been a significant challenge in the field. In response, a first-in-class peptide-based radiotracer, [68Ga]Ga-AJ206, is developed that can be seamlessly integrated into the standard clinical workflow and is specifically designed to noninvasively quantify CD38 levels and pharmacodynamics by positron emission tomography (PET). A bicyclic peptide, AJ206, is synthesized and exhibits high affinity to CD38 (KD: 19.1 ± 0.99 × 10-9 m) by surface plasmon resonance. Further, [68Ga]Ga-AJ206-PET shows high contrast within 60 min and suitable absorbed dose estimates for clinical use. Additionally, [68Ga]Ga-AJ206 detects CD38 expression in cell line-derived xenografts, patient-derived xenografts (PDXs), and disseminated disease models in a manner consistent with flow cytometry and immunohistochemistry findings. Moreover, [68Ga]Ga-AJ206-PET successfully quantifies CD38 pharmacodynamics in PDXs, revealing increased CD38 expression in the tumor following all-trans retinoic acid (ATRA) therapy. In conclusion, [68Ga]Ga-AJ206 exhibits the salient features required for clinical translation, providing CD38-specific high-contrast images in multiple models of MM. [68Ga]Ga-AJ206-PET could be useful for quantifying total CD38 levels and pharmacodynamics during therapy to evaluate approved and new therapies in MM and other diseases with CD38 involvement.


Asunto(s)
ADP-Ribosil Ciclasa 1 , Radioisótopos de Galio , Mieloma Múltiple , Tomografía de Emisión de Positrones , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/metabolismo , Mieloma Múltiple/diagnóstico por imagen , Animales , ADP-Ribosil Ciclasa 1/metabolismo , Ratones , Humanos , Tomografía de Emisión de Positrones/métodos , Radiofármacos/farmacocinética , Modelos Animales de Enfermedad , Péptidos/metabolismo , Glicoproteínas de Membrana/metabolismo , Línea Celular Tumoral
7.
Exp Clin Transplant ; 21(10): 791-800, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37965953

RESUMEN

Inflammatory bowel disease is not uncommon among kidney transplant recipients. In transplant patients with chronic diarrhea and abdominal pain, de novo inflammatory bowel disease can be considered among differential diagnoses, after exclusion of infectious causes and drug-induced diarrhea. Inflammatory bowel disease, in the cnnnontext of organ transplant, is associated with a higherrisk of morbidity, increased rate of hospitalization, and higher mortality.Therefore, a multidisciplinary approach, before and after transplant, among a gastroenterologist specialized in inflammatory bowel disease, a gastrointestinal surgeon, and a transplant clinician is essential, given the higher clinical complexity for this subgroup of patients. Limited data are available on management of inflammatory bowel disease in kidney transplant recipients, although the concurrent use of immunosuppressive therapy can mitigate flare-ups but with increased infection risks. Colorectal cancer can be a serious complication of inflammatory bowel disease; hence, patient compliance with regular colonoscopy surveillance programs is crucial. Patients with inflammatory bowel disease who are undergoing kidney transplant have a shorter overall survival rate compared with matched control groups. However, inferences based on studies involving inflammatory bowel disease in kidney transplant recipients are blighted by small sample sizes,thus making it difficult to draw accurate conclusions. Our review was undertaken to comprehensively report the clinical approaches to kidney transplant recipients with inflammatory bowel disease, describing their clinical course, outcomes, and management plan.


Asunto(s)
Enfermedades Inflamatorias del Intestino , Trasplante de Riñón , Trasplante de Órganos , Humanos , Trasplante de Riñón/efectos adversos , Enfermedades Inflamatorias del Intestino/diagnóstico , Enfermedades Inflamatorias del Intestino/terapia , Enfermedades Inflamatorias del Intestino/complicaciones , Trasplante de Órganos/efectos adversos , Colonoscopía/efectos adversos , Diarrea
8.
Org Lett ; 25(46): 8188-8193, 2023 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-37796466

RESUMEN

Herein, a first-ever heterogeneous Pd/C-catalyzed single-step tandem approach for the synthesis of 2-carboxamidocyclohexane-1,3-diones via direct carbonylative C-H amidation of cyclohexane-1,3-diones is reported. The reaction progressed under base-, oxidant-, and ligand-free conditions employing oxalic acid as a CO surrogate and sodium azide as a nitrogen precursor in a double-layer vial system.

9.
J Immunother Cancer ; 11(10)2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37793856

RESUMEN

BACKGROUND: Combination therapies that aim to improve the clinical efficacy to immune checkpoint inhibitors have led to the need for non-invasive and early pharmacodynamic biomarkers. Positron emission tomography (PET) is a promising non-invasive approach to monitoring target dynamics, and programmed death-ligand 1 (PD-L1) expression is a central component in cancer immunotherapy strategies. [18F]DK222, a peptide-based PD-L1 imaging agent, was investigated in this study using humanized mouse models to explore the relationship between PD-L1 expression and therapy-induced changes in cancer. METHODS: Cell lines and xenografts derived from three non-small cell lung cancers (NSCLCs) and three urothelial carcinomas (UCs) were used to validate the specificity of [18F]DK222 for PD-L1. PET was used to quantify anti-programmed cell death protein-1 (PD-1) therapy-induced changes in PD-L1 expression in tumors with and without microsatellite instability (MSI) in humanized mice. Furthermore, [18F]DK222-PET was used to validate PD-L1 pharmacodynamics in the context of monotherapy and combination immunotherapy in humanized mice bearing A375 melanoma xenografts. PET measures of PD-L1 expression were used to establish a relationship between pathological and immunological changes. Lastly, spatial distribution analysis of [18F]DK222-PET was developed to assess the effects of different immunotherapy regimens on tumor heterogeneity. RESULTS: [18F]DK222-PET and biodistribution studies in mice with NSCLC and UC xenografts revealed high but variable tumor uptake at 60 min that correlated with PD-L1 expression. In MSI tumors treated with anti-PD-1, [18F]DK222 uptake was higher than in control tumors. Moreover, [18F]DK222 uptake was higher in A375 tumors treated with combination therapy compared with monotherapy, and negatively correlated with final tumor volumes. In addition, a higher number of PD-L1+ cells and higher CD8+-to-CD4+ cell ratio was observed with combination therapy compared with monotherapy, and positively correlated with PET. Furthermore, spatial distribution analysis showed higher [18F]DK222 uptake towards the core of the tumors in combination therapy, indicating a more robust and distinct pattern of immune cell infiltration. CONCLUSION: [18F]DK222-PET has potential as a non-invasive tool for monitoring the effects of immunotherapy on tumors. It was able to detect variable PD-L1 expression in tumors of different cancer types and quantify therapy-induced changes in tumors. Moreover, [18F]DK222-PET was able to differentiate the impact of different therapies on tumors.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Animales , Ratones , Antígeno B7-H1 , Distribución Tisular , Tomografía de Emisión de Positrones/métodos , Inmunoterapia/métodos
10.
J Tissue Viability ; 32(4): 550-563, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37414707

RESUMEN

A complete characterization of the burn wound based on cutaneous architectural changes and inflammatory response is extremely important to provide evidence for progressive changes in the burn wound. Burn wounds are highly susceptible to conversion into deeper wounds, which need special care and attention; thereby, the complete characterization of burn wound type and their subsequent inflammatory status in the cutaneous system at the earliest is of paramount importance. Inflammatory markers at different degrees will help clinicians devise better and more specific treatment strategies for each burn type. The present study is carried out to profile pro-inflammatory gene expression along with immune cell quantification, vascular perfusion, and histopathological assessment in the cutaneous system of murine models. The study revealed that burn injury caused an immediate increase in vascular perfusion in superficial and partial-thickness burns, whereas there was a decrease in vascular perfusion in full-thickness burns. An influx of lymphocytes at the edges of burn wounds in each type of burn injury was well-orchestrated with the event of vascular perfusion. Further, pro-inflammatory gene expression profiling revealed significant upregulation vis-à-vis upregulation of TNF-α and MCP-1 genes, with an increase in the number of neutrophils following 72 h of injury that evidently cemented the conversion of superficial burn into partial-thickness burn. The molecular findings were profoundly supported by the histopathological changes. Thus, our foundational studies show distinct characteristic cutaneous changes correlated with the expression of key pro-inflammatory genes in three different types of burn injuries. Characterization of these cutaneous inflammatory responses provides a promising future for medical interventions involved with different degrees of burn injury, and it will also help in the pre-clinical testing of therapies for burn injury.


Asunto(s)
Quemaduras , Traumatismos de los Tejidos Blandos , Humanos , Ratones , Animales , Piel/patología , Factor de Necrosis Tumoral alfa , Neutrófilos , Quemaduras/complicaciones , Quemaduras/terapia
11.
bioRxiv ; 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37214794

RESUMEN

PURPOSE: The limited availability of molecularly targeted low-molecular-weight imaging agents for monitoring multiple myeloma (MM)-targeted therapies has been a significant challenge in the field. In response, we developed [68Ga]Ga-AJ206, a peptide-based radiotracer that can be seamlessly integrated into the standard clinical workflow and is specifically designed to non-invasively quantify CD38 levels and pharmacodynamics by positron emission tomography (PET). EXPERIMENTAL DESIGN: We synthesized a high-affinity binder for quantification of CD38 levels. Affinity was tested using surface plasmon resonance, and In vitro specificity was evaluated using a gallium-68-labeled analog. Distribution, pharmacokinetics, and CD38 specificity of the radiotracer were assessed in MM cell lines and in primary patient-derived myeloma cells and xenografts (PDX) with cross-validation by flow cytometry and immunohistochemistry. Furthermore, we investigated the radiotracer's potential to quantify CD38 pharmacodynamics induced by all-trans retinoic acid therapy (ATRA). RESULTS: [68Ga]Ga-AJ206 exhibited high CD38 binding specificity (KD: 19.1±0.99 nM) and CD38-dependent In vitro binding. [68Ga]Ga-AJ206-PET showed high contrast within 60 minutes and suitable absorbed dose estimates for clinical use. Additionally, [68Ga]Ga-AJ206 detected CD38 expression in xenografts, PDXs and disseminated disease models in a manner consistent with flow cytometry and immunohistochemistry findings. Moreover, [68Ga]Ga-AJ206-PET successfully quantified CD38 pharmacodynamics in PDXs, revealing increased CD38 expression in the tumor following ATRA therapy. CONCLUSIONS: [68Ga]Ga-AJ206 exhibited the salient features required for clinical translation, providing CD38-specific high contrast images in multiple models of MM. [68Ga]Ga-AJ206-PET could be useful for quantifying total CD38 levels and pharmacodynamics during therapy to evaluate approved and new therapies in MM and other diseases with CD38 involvement.

12.
Environ Sci Pollut Res Int ; 30(16): 45570-45586, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36813938

RESUMEN

The demand for freshwater is exponentially rising in today's society, with industrial and manufacturing growth resulting in increased pollution of environmental assets. Therefore, one of the primary challenges for researchers is to produce freshwater using straightforward, inexpensive technology. Around the world, there are various arid and desert areas where ground water is scarce and rainfall is less common. The majority of the world's water sources, including lakes and rivers are brackish or saltwater, making them unsuitable for irrigation, drinking, or even basic household needs. Solar distillation (SD) overcomes the gap between the scarcity and productivity of water. The SD is a technique for purifying water that yields ultrapure water that is superior to bottled water sources. Despite the fact that SD is a straightforward technology, due to its large thermal capacity and lengthy processing times, productivity seems to be low. Researchers have endeavored to create several designs of stills in order to increase yield and have concluded that wick-type solar stills (WSSs) are efficient and effective. When compared to a traditional system, WSS improves efficiency by around 60%. Installing a multi-wick basin-type inverted absorber solar still (MWBIASS) delivers an instantaneous energy efficiency, destroyed exergy percentage and annual cost per kilogram of yield approximately 50.59%, 84.73%, and Rs. 0.91 (0.012 US$), respectively. This comparison review serves as a resource for prospective researchers looking to enhance the performance of WSSs while focusing on the most adroit aspects.


Asunto(s)
Agua Potable , Energía Solar , Purificación del Agua , Agua , Destilación , Estudios Prospectivos , Luz Solar , Purificación del Agua/métodos , Lagos
13.
Mol Biol Cell ; 34(3): ar16, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36652338

RESUMEN

Bacterial cell division proteins, especially the tubulin homologue FtsZ, have emerged as strong targets for developing new antibiotics. Here, we have utilized the fission yeast heterologous expression system to develop a cell-based assay to screen for small molecules that directly and specifically target the bacterial cell division protein FtsZ. The strategy also allows for simultaneous assessment of the toxicity of the drugs to eukaryotic yeast cells. As a proof-of-concept of the utility of this assay, we demonstrate the effect of the inhibitors sanguinarine, berberine, and PC190723 on FtsZ. Though sanguinarine and berberine affect FtsZ polymerization, they exert a toxic effect on the cells. Further, using this assay system, we show that PC190723 affects Helicobacter pylori FtsZ function and gain new insights into the molecular determinants of resistance to PC190723. On the basis of sequence and structural analysis and site-specific mutations, we demonstrate that the presence of salt bridge interactions between the central H7 helix and ß-strands S9 and S10 mediates resistance to PC190723 in FtsZ. The single-step in vivo cell-based assay using fission yeast enabled us to dissect the contribution of sequence-specific features of FtsZ and cell permeability effects associated with bacterial cell envelopes. Thus, our assay serves as a potent tool to rapidly identify novel compounds targeting polymeric bacterial cytoskeletal proteins like FtsZ to understand how they alter polymerization dynamics and address resistance determinants in targets.


Asunto(s)
Berberina , Schizosaccharomyces , Schizosaccharomyces/metabolismo , Antibacterianos/farmacología , Proteínas del Citoesqueleto/metabolismo , Proteínas Bacterianas/metabolismo
14.
Clin Cancer Res ; 29(3): 581-591, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36449662

RESUMEN

PURPOSE: Immune checkpoint therapy (ICT) is currently ineffective in a majority of patients. Tumor drug exposure measurements can provide vital insights into mechanisms involved in the resistance of solid tumors to those therapeutics; however, tools to quantify in situ drug exposure are few. We have investigated the potential of programmed death-ligand 1 (PD-L1) pharmacodynamics, quantified using PET, to inform on the tumor exposure of anti-PD-L1 (aPD-L1) therapeutics. EXPERIMENTAL DESIGN: To noninvasively quantify PD-L1 levels, we first developed a novel peptide-based gallium-68-labeled binder, [68Ga]Ga-DK223, and evaluated its in vivo distribution, pharmacokinetics, and PD-L1 specificity in preclinical models of triple-negative breast cancer and urothelial carcinoma with variable PD-L1 expression. We then quantified baseline and accessible PD-L1 levels in tumors as a noninvasive pharmacodynamic measure to assess tumor exposure to two aPD-L1 antibodies (avelumab and durvalumab). RESULTS: DK223 exhibited a KD of 1.01±0.83 nmol/L for PD-L1 and inhibited the PD-1:PD-L1 interaction in a dose-dependent manner. [68Ga]Ga-DK223 provides high-contrast PET images within 60 minutes of administration and detects PD-L1 in an expression-dependent manner in xenograft models. PD-L1 pharmacodynamics measured using [68Ga]Ga-DK223-PET revealed that avelumab and durvalumab had similar exposure early during therapy, but only durvalumab exhibited sustained exposure at the tumor. CONCLUSIONS: [68Ga]Ga-DK223 detected variable PD-L1 levels and exhibited salient features required for clinical translation. [68Ga]Ga-DK223-PET could be useful for quantifying total PD-L1 levels at baseline and accessible PD-L1 levels during therapy to understand drug exposure at the tumor, thus supporting its use for guiding and optimizing ICT.


Asunto(s)
Carcinoma de Células Transicionales , Neoplasias de la Vejiga Urinaria , Humanos , Tomografía de Emisión de Positrones/métodos , Antígeno B7-H1/metabolismo , Péptidos
15.
J Radiol Prot ; 42(4)2022 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-36317279

RESUMEN

Combined radiation injury occurs when radiation is accompanied by any other form of trauma. The past experiences of Hiroshima, Nagasaki, and Chernobyl have revealed that a large number of victims of such nuclear accidents or attacks suffer from combined radiation injuries. The possibility of a nuclear attack seems very far-fetched, but the destruction that would occur in such an event would be massive, with a huge lossof lives. Therefore, preparedness for the same should be done beforehand. The severity of combined radiation depends upon various factors, such as radiation dose, type, tissues affected, and traumas. The article focuses on combined radiation burn injury (CRBI) which may arise due to the combination of ionising radiation with thermal burns. CRBI can have varied effects on different organs like the hematopoietic, digestive, lymphatic, cardiovascular, and respiratory systems. Some of the most profound lethal effects are hematopoietic dysfunction, gastrointestinal leakage, bacterial translocation to other organ sites, pulmonary fibrosis, and pneumonitis. In this article, we have attempted to accumulate the knowledge of ongoing research on the functioning of different organ systems, which are affected due to CRBI and possible countermeasures to minimize the effects, thus improving survival.


Asunto(s)
Quemaduras , Traumatismos por Radiación , Liberación de Radiactividad Peligrosa , Humanos , Quemaduras/complicaciones , Traumatismos por Radiación/complicaciones
16.
Indian Heart J ; 74(5): 363-368, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36007555

RESUMEN

OBJECTIVES: This prospective, randomized study assessed short-term outcomes and safety of ultra-low contrast percutaneous coronary intervention(ULC-PCI) vs conventional PCI in high risk for contrast induced acute kidney injury(CI-AKI) patients presenting with acute coronary syndrome(ACS). BACKGROUND: Patients at an increased risk of developing CI-AKI can be identified prior to PCI based on their pre-procedural risk scores. ULC-PCI is a novel contrast conservation strategy in such high risk patients for prevention of CI-AKI. METHODS: 82 patients undergoing PCI for ACS were enrolled having estimated glomerular filtration rate(eGFR) < 60 ml/min/1.73 m2 and moderate to very high pre-procedural risk of developing CI-AKI as calculated by Maioli risk calculator. They were randomized into two groups of 41 patients each of ULC-PCI (contrast volume ≤ patient's eGFR) and conventional PCI (contrast volume ≤ 3xpatient's eGFR). Primary end point was development of CI-AKI. RESULTS: Baseline clinical and angiographic characteristics were similar between groups. Primary outcome of CI-AKI occurred more in patients of the conventional PCI group [7 (17.1%)] than in the ULC PCI group [(0 patients), p = 0.012]. Contrast volume (41.02 (±9.8) ml vs 112.54 (±25.18) ml; P < 0.0001) was markedly lower in the ULC-PCI group. No significant difference in secondary safety outcomes between two study arms at 30 days. IVUS was used in 17% patients in ULC PCI. CONCLUSION: ULC-PCI in patients with increased risk of developing CI-AKI is feasible, appears safe, and has the potential to decrease the incidence of CI-AKI specially in resource limited setting such as ours where coronary imaging by IVUS is not possible in every patient.


Asunto(s)
Lesión Renal Aguda , Intervención Coronaria Percutánea , Humanos , Intervención Coronaria Percutánea/métodos , Medios de Contraste/efectos adversos , Resultado del Tratamiento , Lesión Renal Aguda/etiología , Tasa de Filtración Glomerular , Factores de Riesgo , Angiografía Coronaria/métodos
18.
Drug Chem Toxicol ; 45(2): 594-603, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32160796

RESUMEN

In India, traditional herbal medicines have been an essential part of therapy for the last centuries. However, a large portion of the general populace is using these therapies in combination with allopathy lacking a proper understanding of possible interactions (synergistic or antagonistic) between the herbal product and the allopathic drug. This is based on the assumption that herbal drugs are relatively safe, i.e. without side effects. We have established a comprehensive understanding of the possible herb-drug interactions and identified interaction patterns between the most common herbs and drugs currently in use in the Indian market. For this purpose, we listed common interactors (herbs and allopathic drugs) using available scientific literature. Drugs were then categorized into therapeutic classes and aligned to produce a recognizable pattern present only if interactions were observed between a drug class and herb in the scientific literature. Interestingly, the top three categories (with highest interactors), antibiotics, oral hypoglycemics, and anticonvulsants, displayed synergistic interactions only. Another major interactor category was CYP450 enzymes, a natural component of our metabolism. Both activation and inhibition of CYP450 enzymes were observed. As many allopathic drugs are known CYP substrates, inhibitors or inducers, ingestion of an interacting herb could result in interaction with the co-administered drug. This information is largely unavailable for the Indian population and should be studied in greater detail to avoid such interactions. Although this information is not absolute, the systematic literature review proves the existence of herb-drug interactions in the literature and studies where no interaction was detected are equally important.


Asunto(s)
Preparaciones Farmacéuticas , Plantas Medicinales , Sistema Enzimático del Citocromo P-450/metabolismo , Interacciones de Hierba-Droga , India , Plantas Medicinales/metabolismo
19.
J Biomol Struct Dyn ; 40(22): 11545-11559, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34348081

RESUMEN

A well-validated in-silico approach can provide promising drug candidates for the treatment of the ongoing CoVID19 pandemic. In this study, we have screened 32 phytochemical constituents (PCCs) with Mpro binding site (PDB:6W63) based on which we identified three possible candidates that are likely to be effective against CoVID19-viz., licoleafol (binding energy: -8.1 kcal/mol), epicatechin gallate (-8.5 kcal/mol) and silibinin (-8.4 kcal/mol) that result in higher binding affinity than the known inhibitor, X77 (-7.7 kcal/mol). Molecular dynamics (MD) simulations of PCCs-Mpro complex confirmed molecular docking results with high structural and dynamical stability. The selected compounds were found to exhibit low mean squared displacements (licoleafol: 2.25 ± 0.43 Å, epicatechin gallate: 1.93 ± 0.35 Å, and silibinin: 1.39 ± 0.19 Å) and overall low fluctuations of the binding complexes (root mean squared fluctuations below 2 Å). Visualization of the MD trajectories and structural analyses revealed that they remain confined to the initial binding region, with mean fluctuations lower than 3 Å. To access the collective motion of the atoms, we performed principal component analysis demonstrating that the first 10 principal components are the major contributors (approximate contribution of 80%) and are responsible for the overall PCCs motion. Considering that the three selected PCCs share the same flavan backbone and exhibit antiviral activity against hepatitis C, we opine that licoleafol, epi-catechin gallate, and silibinin can be promising anti-CoVID19 drug candidates. Communicated by Ramaswamy H. Sarma.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Simulación del Acoplamiento Molecular , Silibina/farmacología , Antivirales/farmacología , Simulación de Dinámica Molecular , Inhibidores de Proteasas
20.
Curr Pharm Biotechnol ; 23(2): 287-299, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33719970

RESUMEN

BACKGROUND: Sulfur Mustard is a strong vesicant and chemical warfare agent that imposes toxicity to the lungs, eyes, and skin after accidental or intended exposure. OBJECTIVES: The current study was intended to explore in vitro and in vivo decontamination properties of electrolytically generated HOCl (hypochlorous acid) against CEES (2-chloroethyle ethyle sulphide), a known sulfur mustard simulant & vesicating agent. METHODS: in vitro studies were carried out using UV spectroscopy and GC-MS methods. In vivo studies were performed in Strain A and immune-compromised mice by subcutaneous as well as prophylactic topical administration of HOCl pretreated CEES. The blister formation and mortality were considered as end-point. Histopathological study was conducted on skin samples by H & E method. DNA damage studies measuring γ-H2AX and ATM have been carried out in human blood using flow cytometry. Anti-bacterial action was tested by employing broth micro dilution methods. A comparative study was also carried out with known oxidizing agents. RESULTS: The topical application of pre-treated CEES at 5, 30 min and 1 h time points showed significant (p<0.001) inhibition of blister formation. DNA damage study showed reduced mean fluorescence intensity of DSBs nearly 17-20 times, suggesting that HOCl plays a protective role against DNA damage. Histopathology showed no sign of necrosis in the epidermis upto 5 min although moderate changes were observed at 30 min. Pretreated samples were analyzed for detection of reaction products with m/z value of 75.04, 69.08, 83.93, 85.95, 123.99, 126.00, and 108.97. HOCl showed a strong bactericidal effect at 40 ppm. The absorbance spectra of HOCl treated CEES showed lowered peaks in comparison to CEES alone and other oxidizing agents. CONCLUSION: In a nutshell, our results signify the decontamination role of HOCl for biological surface application.


Asunto(s)
Sustancias para la Guerra Química , Gas Mostaza , Animales , Sustancias para la Guerra Química/farmacología , Descontaminación , Ácido Hipocloroso/farmacología , Ratones , Gas Mostaza/farmacología , Piel
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