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1.
bioRxiv ; 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38328206

RESUMO

Tuberculosis (TB), caused by the bacterium Mycobacterium tuberculosis (M.tb), remains a significant health concern worldwide, especially in populations with weakened or compromised immune systems, such as the elderly. Proper adaptive immune function, particularly a CD4+ T cell response, is central to host immunity against M.tb. Chronic infections, such as M.tb, as well as aging promote T cell exhaustion and senescence, which can impair immune control and promote progression to TB disease. Mitochondrial dysfunction contributes to T cell dysfunction, both in aging and chronic infections and diseases. Mitochondrial perturbations can disrupt cellular metabolism, enhance oxidative stress, and impair T-cell signaling and effector functions. This study examined the impact of mitochondrial transplantation (mito-transfer) on CD4+ T cell differentiation and function using aged mouse models and human CD4+ T cells from elderly individuals. Our study revealed that mito-transfer in naïve CD4+ T cells promoted the generation of protective effector and memory CD4+ T cells during M.tb infection in mice. Further, mito-transfer enhanced the function of elderly human T cells by increasing their mitochondrial mass and modulating cytokine production, which in turn reduced exhaustion and senescence cell markers. Our results suggest that mito-transfer could be a novel strategy to reestablish aged CD4+ T cell function, potentially improving immune responses in the elderly and chronic TB patients, with a broader implication for other diseases where mitochondrial dysfunction is linked to T cell exhaustion and senescence.

2.
Geroscience ; 46(3): 2901-2913, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38388916

RESUMO

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is still an ongoing global health crisis. Clinical data indicate that the case fatality rate (CFR) is age dependent, with a higher CFR percentage in the elderly population. We compared the pathogenesis of SARS-CoV-2 in young and aged K18-hACE2 transgenic mice. We evaluated morbidity, mortality, viral titers, immune responses, and histopathology in SARS-CoV-2-infected young and old K18-hACE2 transgenic mice. Within the limitation of having a low number of mice per group, our results indicate that SARS-CoV-2 infection resulted in slightly higher morbidity, mortality, and viral replication in the lungs of old mice, which was associated with an impaired IgM response and altered cytokine and chemokine profiles. Results of this study increase our understanding of SARS-CoV-2 infectivity and immuno-pathogenesis in the elderly population.


Assuntos
COVID-19 , Melfalan , gama-Globulinas , Idoso , Humanos , Animais , Camundongos , Camundongos Transgênicos , SARS-CoV-2 , Citocinas , Modelos Animais de Doenças
3.
J Mol Graph Model ; 128: 108702, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38219505

RESUMO

In recent years, Onco-immunotherapies (OIMTs) have been shown to be a potential therapy option for cancer. Several immunotherapies have received regulatory approval, while many others are now undergoing clinical testing or are in the early stages of development. Despite this progress, a large number of challenges to the broad use of immunotherapies to treat cancer persists. To make immunotherapy more useful as a treatment while reducing its potentially harmful side effects, we need to know more about how to improve response rates to different types of immunotherapies. Nanocarriers (NCs) have the potential to harness immunotherapies efficiently, enhance the efficiency of these treatments, and reduce the severe adverse reactions that are associated with them. This article discusses the necessity to incorporate nanomedicines in OIMTs and the challenges we confront with current anti-OIMT approaches. In addition, it examines the most important considerations for building nanomedicines for OIMT, which may improve upon current immunotherapy methods. Finally, it highlights the applications and future scenarios of using nanotechnology.


Assuntos
Sistemas de Liberação de Medicamentos , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Imunoterapia , Nanomedicina
4.
Adv Sci (Weinh) ; 11(5): e2303664, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37990641

RESUMO

Mitochondrial dysfunction alters cellular metabolism, increases tissue oxidative stress, and may be principal to the dysregulated signaling and function of CD4+ T lymphocytes in the elderly. In this proof of principle study, it is investigated whether the transfer of functional mitochondria into CD4+ T cells that are isolated from old mice (aged CD4+ T cells), can abrogate aging-associated mitochondrial dysfunction, and improve the aged CD4+ T cell functionality. The results show that the delivery of exogenous mitochondria to aged non-activated CD4+ T cells led to significant mitochondrial proteome alterations highlighted by improved aerobic metabolism and decreased cellular mitoROS. Additionally, mito-transferred aged CD4+ T cells showed improvements in activation-induced TCR-signaling kinetics displaying markers of activation (CD25), increased IL-2 production, enhanced proliferation ex vivo. Importantly, immune deficient mouse models (RAG-KO) showed that adoptive transfer of mito-transferred naive aged CD4+ T cells, protected recipient mice from influenza A and Mycobacterium tuberculosis infections. These findings support mitochondria as targets of therapeutic intervention in aging.


Assuntos
Envelhecimento , Doenças Mitocondriais , Humanos , Idoso , Camundongos , Animais , Linfócitos T CD4-Positivos , Linfócitos T Reguladores , Mitocôndrias
5.
J Control Release ; 365: 43-59, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37935257

RESUMO

Imprecise targeting of chemotherapeutic drugs often leads to severe toxicity during breast cancer therapy. To address this issue, we have devised a strategy to load dacarbazine (DC) into fucose-based carbon quantum dots (CQDs), which are subsequently coated with exosomes (Ex-DC@CQDs) derived from breast cancer cells. Nanoparticle tracking analysis and western blotting revealed that Ex-DC@CQDs retained the structural and functional characteristics of exosomes. We found that exosomes facilitated the transport of DC@CQDs to cancer cells via heparan sulfate proteoglycan (HSPG) receptors, followed by an augmented depolarization of the mitochondrial membrane potential, ROS generation, and induction of apoptosis leading to cell death. In vivo imaging and pharmacokinetic studies demonstrated enhanced antitumor targeting and efficacy compared to free DC which we attribute to an improved pharmacokinetic profile, a greater tumor accumulation via exosome-mediated- HSPG receptor-driven cell uptake, and sustained release of the Ex-DC@CQDs. Our findings may pave the way for the further development of biologically sourced nanocarriers for breast cancer targeting.


Assuntos
Neoplasias da Mama , Exossomos , Pontos Quânticos , Humanos , Feminino , Pontos Quânticos/química , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Exossomos/metabolismo , Dacarbazina , Proteoglicanas de Heparan Sulfato/metabolismo , Carbono/química
6.
Wiley Interdiscip Rev Cogn Sci ; 15(1): e1663, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37525620

RESUMO

Counterfactual thinking is a relatively late emerging ability in childhood with key implications for emerging social cognition and behavior.


Assuntos
Cognição Social , Pensamento , Criança , Humanos , Cognição
7.
Cogn Emot ; 38(1): 163-170, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37743725

RESUMO

Recent research has provided compelling evidence that children experience the negative counterfactual emotion of regret, by manipulating the presence of a counterfactual action that would have led to participants receiving a better outcome. However, it remains unclear if children similarly experience regret's positive counterpart, relief. The current study examined children's negative and positive counterfactual emotions in a novel gain-or-loss context. Four- to 9-year-old children (N = 136) were presented with two opaque boxes concealing information that would lead to a gain or loss of stickers, respectively. Half of the children chose between two keys that matched each box, whereas the other half were compelled to select one box because only one of the two keys matched. After seeing inside the alternative, non-chosen box, children were significantly more likely to report a change in emotion when they could have opened that box than when they could not have. The effects were similar for children who lost stickers and won stickers, and neither effect varied with age. These findings suggest that children may become capable of experiencing regret and relief around the same time, although their expression of these counterfactual emotions may vary with actual and counterfactual gains and losses.


Assuntos
Comportamento de Escolha , Emoções , Criança , Humanos , Pré-Escolar
8.
Biomacromolecules ; 24(12): 5780-5796, 2023 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-38006339

RESUMO

In the current study, we aimed to develop lyotropic crystalline nanoconstructs (LCNs) based on poly(l-glutamic acid) (PLG) with a two-tier strategy. The first objective was to confer pH-responsive charge conversion properties to facilitate the delivery of both doxorubicin (DOX) and buparvaquone (BPQ) in combination (B + D@LCNs) to harness their synergistic effects. The second goal was to achieve targeted delivery to sigma receptors within the tumor tissues. To achieve this, we designed a pH-responsive charge conversion system using a polymer consisting of poly(ethylenimine), poly(l-lysine), and poly(l-glutamic acid) (PLG), which was then covalently coupled with methoxybenzamide (MBA) for potential sigma receptor targeting. The resulting B + D@LCNs were further modified by surface functionalization with PLG-MBA to confer both sigma receptor targeting and pH-responsive charge conversion properties. Our observations indicated that at physiological pH 7.4, P/B + D-MBA@LCNs exhibited a negative charge, while under acidic conditions (pH 5.5, characteristic of the tumor microenvironment), they acquired a positive charge. The particle size of P/B + D-MBA@LCNs was determined to be 168.23 ± 2.66 nm at pH 7.4 and 201.23 ± 1.46 nm at pH 5.5. The crystalline structure of the LCNs was confirmed through small-angle X-ray scattering (SAXS) diffraction patterns. Receptor-mediated endocytosis, facilitated by P/B + D-MBA@LCNs, was confirmed using confocal laser scanning microscopy and flow cytometry. The P/B + D-MBA@LCNs formulation demonstrated a higher rate of G2/M phase arrest (55.20%) compared to free B + D (37.50%) and induced mitochondrial depolarization (59.39%) to a greater extent than P/B + D@LCNs (45.66%). Pharmacokinetic analysis revealed significantly improved area under the curve (AUC) values for both DOX and BPQ when administered as P/B + D-MBA@LCNs, along with enhanced tumor localization. Tumor regression studies exhibited a substantial reduction in tumor size, with P/B + D-MBA@LCNs leading to 3.2- and 1.27-fold reductions compared to B + D and nontargeted P/B + D@LCNs groups, respectively. In summary, this two-tier strategy demonstrates substantial promise for the delivery of a drug combination through the prototype formulation. It offers a potential chemotherapeutic option by minimizing toxic effects on healthy cells while maximizing therapeutic efficacy.


Assuntos
Neoplasias da Mama , Nanopartículas , Receptores sigma , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Ácido Glutâmico , Espalhamento a Baixo Ângulo , Difração de Raios X , Doxorrubicina/química , Concentração de Íons de Hidrogênio , Receptores sigma/uso terapêutico , Nanopartículas/química , Portadores de Fármacos/química , Microambiente Tumoral
9.
Biomater Adv ; 155: 213672, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37976833

RESUMO

In the present investigation, we have strategically synthesized Glutathione (GSH) stimuli-sensitive analogues using carbamate linkers (CL) of DOX (DOX-CL) and RB (RB-CL) which were then anchored to gold nanoparticles (Au-DOX-CL, Au-RB-CL) using mPEG as a spacer. It was observed that carbamate linkage (CL) with four carbon spacer is critical, to position the terminal thiol group, to access the carbamate group efficiently to achieve GSH-assisted release of DOX and RB in tumor-specific environment. When assessed for GSH reductase activity in MDA-MB 231 cell lines, Au-DOX-CL and Au-RB-CL showed nearly 4.18 and 3.13 fold higher GSH reductive activity as compared to the control group respectively. To achieve spatial tumor targeting with a high payload of DOX and RB, Au-DOX-CL and Au-RB-CL were encapsulated in the cell-penetrating peptide (CPP) modified liquid crystalline cubosomes i.e. CPP-Cu(Au@CL-DR). After internalization, the prototype nanocarriers release respective drugs at a precise GSH concentration inside the tumor tissues, amplifying drug concentration to a tune of five-fold. The drug concentrations remain within the therapeutic window for 72 h with a significant reduction of RB (7.8-fold) and DOX (6-fold) concentrations in vital organs, rendering reduced toxicity and improved survival. Overall, this constitutes a promising chemotherapeutic strategy against cancer and its potential application in the offing.


Assuntos
Nanopartículas Metálicas , Neoplasias , Humanos , Portadores de Fármacos/química , Ouro/química , Carbamatos , Nanopartículas Metálicas/química , Doxorrubicina/farmacologia , Doxorrubicina/química , Doxorrubicina/uso terapêutico , Neoplasias/tratamento farmacológico , Glutationa/química
10.
J Control Release ; 363: 290-348, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37714434

RESUMO

Nanovesicles and bio-vesicles (BVs) have emerged as promising tools to achieve targeted cancer therapy due to their ability to overcome many of the key challenges currently being faced with conventional chemotherapy. These challenges include the diverse and often complex pathophysiology involving the progression of cancer, as well as the various biological barriers that circumvent therapeutic molecules reaching their target site in optimum concentration. The scientific evidence suggests that surface-functionalized nanovesicles and BVs camouflaged nano-carriers (NCs) both can bypass the established biological barriers and facilitate fourth-generation targeting for the improved regimen of treatment. In this review, we intend to emphasize the role of surface-functionalized nanovesicles and BVs camouflaged NCs through various approaches that lead to an improved internalization to achieve improved and targeted oncotherapy. We have explored various strategies that have been employed to surface-functionalize and biologically modify these vesicles, including the use of biomolecule functionalized target ligands such as peptides, antibodies, and aptamers, as well as the targeting of specific receptors on cancer cells. Further, the utility of BVs, which are made from the membranes of cells such as mesenchymal stem cells (MSCs), white blood cells (WBCs), red blood cells (RBCs), platelets (PLTs) as well as cancer cells also been investigated. Lastly, we have discussed the translational challenges and limitations that these NCs can encounter and still need to be overcome in order to fully realize the potential of nanovesicles and BVs for targeted cancer therapy. The fundamental challenges that currently prevent successful cancer therapy and the necessity of novel delivery systems are in the offing.


Assuntos
Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Ligantes , Peptídeos/uso terapêutico
11.
Immunohorizons ; 7(6): 412-420, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37279084

RESUMO

Mechanisms to shorten the duration of tuberculosis (TB) treatment include new drug formulations or schedules and the development of host-directed therapies (HDTs) that better enable the host immune system to eliminate Mycobacterium tuberculosis. Previous studies have shown that pyrazinamide, a first-line antibiotic, can also modulate immune function, making it an attractive target for combinatorial HDT/antibiotic therapy, with the goal to accelerate clearance of M. tuberculosis. In this study, we assessed the value of anti-IL-10R1 as an HDT along with pyrazinamide and show that short-term anti-IL-10R1 blockade during pyrazinamide treatment enhanced the antimycobacterial efficacy of pyrazinamide, resulting in faster clearance of M. tuberculosis in mice. Furthermore, 45 d of pyrazinamide treatment in a functionally IL-10-deficient environment resulted in sterilizing clearance of M. tuberculosis. Our data suggest that short-term IL-10 blockade with standard TB drugs has the potential to improve clinical outcome by reducing the treatment duration.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Animais , Camundongos , Pirazinamida/farmacologia , Pirazinamida/uso terapêutico , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Interleucina-10
12.
Child Dev ; 94(5): e296-e307, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37226682

RESUMO

When making moral judgments of past actions, adults often think counterfactually about what could have been done differently. Considerable evidence suggests that counterfactual thinking emerges around age 6, but it remains unknown how this development influences children's moral judgments. Across two studies, Australian children aged 4-9 (N = 236, 142 Females) were told stories about two characters who had a choice that led to a good or bad outcome, and two characters who had no choice over a good or bad outcome. Results showed that 4- and 5-year-olds' moral judgments were influenced only by the actual outcome. From age 6, children's moral judgments were also influenced by the counterfactual choices that had been available to the characters.


Assuntos
Julgamento , Princípios Morais , Adulto , Feminino , Criança , Humanos , Pré-Escolar , Austrália , Desenvolvimento Infantil
13.
Colloids Surf B Biointerfaces ; 226: 113316, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37086687

RESUMO

Chondroitin anchored crystalline nano-capsules bearing Imatinib (IMT), and simvastatin (SMV) was developed using Poly (L-lactic acid) (PLLA) by two-step method, i.e., firstly, by synthesizing chondroitin (CSA) anchored simvastatin (SMV) using cystamine as a spacer (SMV-SS-CSA) for disulfide triggered glutathione (GSH) sensitive release and secondly, by developing phenyl boronic ester grafted Pluronic F68 (PEPF) for H2O2 responsive release. By combining these conjugates, we have prepared crystalline nano-capsules (CNs) for preferential targeting of CD44 receptors. The developed CNs were spherical when characterized through SEM, TEM, and AFM for surface morphology, while changes in particle size and crystalline structure were confirmed through Quasi-Elastic light scattering (QELS) and Wide Angle X-ray Scattering (WAXS). The enhanced cellular uptake was noted in chondroitin-modified nano-capsules IMT/SMV-SS-CSA@CNs compared to unmodified nano-capsules IMT+SMV@CNs. IMT/SMV-SS-CSA@CNs displayed significantly higher G2/M phase arrest (76.9%) than unmodified nano-capsules. The prototype formulation (IMT/SMV-SS-CSA@CNs) showed an overall improved pharmacokinetic profile in terms of both half-life and AUC0-α. When tested in the 4T1 subcutaneously injected tumor-bearing Balb/c mice model, the tumor growth inhibition rate of IMT/SMV-SS-CSA@CNs was significantly higher (91%) than the IMT+SMV combination. Overall, the findings suggest that the proposed dual responsive chondroitin-modified drug delivery could have a step forward in achieving spatial and temporal targeting at the tumor site.


Assuntos
Peróxido de Hidrogênio , Neoplasias , Animais , Camundongos , Mesilato de Imatinib/farmacologia , Sinvastatina , Condroitina , Oxirredução
14.
Mol Pharm ; 20(4): 1914-1932, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36848489

RESUMO

A two-tier approach has been proposed for targeted and synergistic combination therapy against metastatic breast cancer. First, it comprises the development of a paclitaxel (PX)-loaded redox-sensitive self-assembled micellar system using betulinic acid-disulfide-d-α-tocopheryl poly(ethylene glycol) succinate (BA-Cys-T) through carbonyl diimidazole (CDI) coupling chemistry. Second, hyaluronic acid is anchored to TPGS (HA-Cys-T) chemically through a cystamine spacer to achieve CD44 receptor-mediated targeting. We have established that there is significant synergy between PX and BA with a combination index of 0.27 at a molar ratio of 1:5. An integrated system comprising both BA-Cys-T and HA-Cys-T (PX/BA-Cys-T-HA) exhibited significantly higher uptake than PX/BA-Cys-T, indicating preferential CD44-mediated uptake along with the rapid release of drugs in response to higher glutathione concentrations. Significantly higher apoptosis (42.89%) was observed with PX/BA-Cys-T-HA than those with BA-Cys-T (12.78%) and PX/BA-Cys-T (33.38%). In addition, PX/BA-Cys-T-HA showed remarkable enhancement in the cell cycle arrest, improved depolarization of the mitochondrial membrane potential, and induced excessive generation of ROS when tested in the MDA-MB-231 cell line. An in vivo administration of targeted micelles showed improved pharmacokinetic parameters and significant tumor growth inhibition in 4T1-induced tumor-bearing BALB/c mice. Overall, the study indicates a potential role of PX/BA-Cys-T-HA in achieving both temporal and spatial targeting against metastatic breast cancer.


Assuntos
Nanoestruturas , Neoplasias , Animais , Camundongos , Paclitaxel/química , Sistemas de Liberação de Medicamentos , Micelas , Oxirredução , Ácido Hialurônico/química , Linhagem Celular Tumoral
16.
Philos Trans R Soc Lond B Biol Sci ; 377(1866): 20210346, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-36314147

RESUMO

Adults often reason about what might have happened had they chosen an alternative course of action in the past, which can elicit the counterfactual emotion of regret. It is unclear whether young children's emotions are similarly impacted by counterfactual thinking about past possibilities. In this study, 4- to 9-year-old children (N = 160) opened one of two boxes, which concealed small and large prizes, respectively. Some children had the means to open either box, whereas other children only had the means to open one box. After seeing that the prize they did not obtain was larger than the one they did obtain, children were significantly more likely to report a negative change in emotion when the non-obtained prize had been a straightforward counterfactual possibility than when it had not. This shows that even young children experience counterfactual emotions following choices, which may ultimately drive them to make better choices in the future. This article is part of the theme issue 'Thinking about possibilities: mechanisms, ontogeny, functions and phylogeny'.


Assuntos
Emoções , Criança , Adulto , Humanos , Pré-Escolar
17.
Life Sci ; 309: 121020, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36191680

RESUMO

AIMS: Postmenopausal osteoporosis is one of the world's biggest yet unnoticed health issues. After ovariectomy, declined estrogen level significantly contributes to the elevation of bone marrow adiposity and bone loss leading to osteoporosis. Therapeutics to prevent osteoporosis addressing various aspects are now in short supply. In this study we made an approach to synthesize nanoparticles of naturally occurring PPAR-γ inhibitor, betulinic acid (BA/NPs) and tested the same in altered bone metabolisms developed after ovariectomy. MAIN METHODS: The osteogenic efficacy of BA/NPs was established in human and rat primary osteoblast cells using qRT-PCR and immunoblot analysis. Furthermore, lineage allocations of multipotent bone marrow stromal cells were evaluated. Various aspects of altered bone metabolism after ovariectomy such as bone marrow adiposity and pathological bone loss were evaluated using µCT and histological assessments. KEY FINDINGS: BA/NPs exert potential osteogenic efficacy by modulating key osteogenic markers such as RUNX2 and BMP2. Mechanistically BA/NPs regulate osteoblastogenesis through Wnt/ß-catenin signaling. Further, BA/NPs showed the potential to inhibit the differentiation of multipotent BMSCs towards adipogenesis while favouring the osteogenic lineage via Wnt/ß-catenin pathway. In the in vivo study, increased bone marrow adiposity was reduced in ovariectomized rats after BA/NPs treatment as assessed by histology and µCT analysis. Loss of bone mineral density as a hallmark of pathological bone loss was also abrogated by BA/NPs. Furthermore, increased obesity after OVX was also prevented in BA/NPs treated animals. SIGNIFICANCE: Our findings imply that BA/NPs could be used further as a viable drug lead to counteract various pathophysiological challenges after menopause.


Assuntos
Nanopartículas , Osteoporose , Feminino , Ratos , Humanos , Animais , beta Catenina/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Medula Óssea/metabolismo , Adiposidade , PPAR gama/metabolismo , Via de Sinalização Wnt , Osteogênese , Diferenciação Celular , Osteoporose/tratamento farmacológico , Osteoporose/etiologia , Osteoporose/metabolismo , Ovariectomia , Estrogênios/uso terapêutico , Obesidade , Ácido Betulínico
18.
Environ Technol ; : 1-12, 2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-35848153

RESUMO

ABSTRACTIndia is an agricultural country and near about 500 MT of agricultural wastes are generated each year. India has huge reserves of low-grade iron ore fines. Therefore, considering the availability of these two, the present study mainly focuses on utilization of solid waste in iron and steel industry; also, biomass being carbon-neutral fuel, promotes mitigation of environmental issues. To carry out this study, agricultural wastes like groundnut shell and corn cob which contain more than 70% of volatile matter were considered. Hence, an attempt has been taken to utilize this volatiles as well as char (prepared at 350°C) of corn cob and groundnut shell as a reducing agent for reduction of iron ore pellets. Maximum reduction percentage was achieved at 1000°C and 75 min using corn cob as a reductant, i.e. 78.38% with its volatile and 92.01% using its char. Higher intensity of elemental iron is also reflected by X-ray Diffraction analysis of reduced pellets. Further, cost estimation of reduction of iron ore pellets was also done using both the reducing agents, which signifies that the reduction process using biomass volatiles is much more economical than biochar. The total cost of producing DRI from corn cob volatiles is 56% less than coal followed by groundnut shell volatiles 53.36% and minimum in the case of groundnut shell char 36.17%.Highlights Effects of biomass volatiles and char on iron ore pellets reduction @ 1000°C at different time interval of 15, 30, 45, 60 & 75 min.Comparative assessment of iron ore pellets reduction through XRD and FESEM analysis.Economic evaluation of iron ore reduction using volatiles and char of biomass.

19.
J Control Release ; 346: 43-70, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35405165

RESUMO

The multi-dimensional challenge of drug resistance is one of the pivotal hindrances for cancer chemotherapy. A reductive approach to define and distinguish the main aspects of drug resistance, such as tumor growth kinetics about tumor micro-environment (tumor multifariousness), therapeutic pressure, physical barricades, irreversible genetic mutation, as well as role of the immune system, are the main causes of failure in cancer therapy are presented systematically. We are focusing on general approaches to reduce drug resistance: earlier diagnosis of tumors allowing for cancer halting; dynamic surveillance throughout treatment; the adding of new therapeutic strategies and improve pharmacodynamics precepts resulting in profound effects; and identification of cancerous cells repositories using high-throughput monitoring, as well as the interoperability of clinical- gene mapping statics are described in detail. These strategies could be potentially constructed for any tumor at any precise moment and used to guide therapy selection. Chemotherapeutic agents results in mild improved survival in clinical trials owing to several pathophysiologic obstacles, such as intra-tumoral dispersion, invasion & intra-cellular transportation. This review highlights recent advancements in developing new therapeutic innovations to combat drug resistance in cancer therapy by overcoming various barricades in the tumor microenvironment.


Assuntos
Antineoplásicos , Neoplasias , Resistencia a Medicamentos Antineoplásicos , Humanos , Mutação , Neoplasias/patologia , Microambiente Tumoral
20.
J Immunol ; 208(6): 1406-1416, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35181640

RESUMO

Mycobacterium bovis bacillus Calmette-Guérin (BCG) immunization still remains the best vaccination strategy available to control the development of active tuberculosis. Protection afforded by BCG vaccination gradually wanes over time and although booster strategies have promise, they remain under development. An alternative approach is to improve BCG efficacy through host-directed therapy. Building upon prior knowledge that blockade of IL-10R1 during early Mycobacterium tuberculosis infection improves and extends control of M. tuberculosis infection in mice, we employed a combined anti-IL-10R1/BCG vaccine strategy. An s.c. single vaccination of BCG/anti-IL10-R1 increased the numbers of CD4+ and CD8+ central memory T cells and reduced Th1 and Th17 cytokine levels in the lung for up to 7 wk postvaccination. Subsequent M. tuberculosis challenge in mice showed both an early (4 wk) and sustained long-term (47 wk) control of infection, which was associated with increased survival. In contrast, protection of BCG/saline-vaccinated mice waned 8 wk after M. tuberculosis infection. Our findings demonstrate that a single and simultaneous vaccination with BCG/anti-IL10-R1 sustains long-term protection, identifying a promising approach to enhance and extend the current BCG-mediated protection against TB.


Assuntos
Mycobacterium bovis , Mycobacterium tuberculosis , Tuberculose , Animais , Vacina BCG , Camundongos , Receptores de Interleucina-10 , Tuberculose/prevenção & controle , Vacinação
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