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1.
J Exp Biol ; 227(8)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38516876

RESUMO

Artificial light at night (ALAN) is a growing environmental problem influencing the fitness of individuals through effects on their physiology and behaviour. Research on animals has primarily focused on effects on behaviour during the night, whereas less is known about effects transferred to daytime. Here, we investigated in the lab the impact of ALAN on the mating behaviour of an ecologically important freshwater amphipod, Gammarus pulex, during both daytime and nighttime. We manipulated the presence of ALAN and the intensity of male-male competition for access to females, and found the impact of ALAN on mating activity to be stronger during daytime than during nighttime, independent of male-male competition. At night, ALAN only reduced the probability of precopula pair formation, while during the daytime, it both decreased general activity and increased the probability of pair separation after pair formation. Thus, ALAN reduced mating success in G. pulex not only directly, through effects on mating behaviour at night, but also indirectly through a carry-over effect on daytime activity and the ability to remain in precopula. These results emphasise the importance of considering delayed effects of ALAN on organisms, including daytime activities that can be more important fitness determinants than nighttime activities.


Assuntos
Anfípodes , Humanos , Animais , Feminino , Masculino , Poluição Luminosa , Comportamento Animal/fisiologia , Reprodução , Luz
2.
J Immunol ; 202(4): 1229-1238, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30651343

RESUMO

AG-30/5C is an angiogenic host defense peptide that activates human mast cells (MC) via an unknown mechanism. Using short hairpin RNA-silenced human MC line LAD2 and stably transfected RBL-2H3 cells, we demonstrate that AG-30/5C induces MC degranulation via Mas-related G protein-coupled receptor X2 (MRGPRX2). Most G protein-coupled receptors signal via parallel and independent pathways mediated by G proteins and ß-arrestins. AG-30/5C and compound 48/80 induced similar maximal MC degranulation via MRGPRX2, which was abolished by pertussis toxin. However, compound 48/80 induced a robust ß-arrestin activation as determined by transcriptional activation following arrestin translocation (Tango), but AG-30/5C did not. Overnight culture of MC with compound 48/80 resulted in reduced cell surface MRGPRX2 expression, and this was associated with a significant decrease in subsequent MC degranulation in response to compound 48/80 or AG-30/5C. However, AG-30/5C pretreatment had no effect on cell surface MRGPRX2 expression or degranulation in response to compound 48/80 or AG-30/5C. Icatibant, a bradykinin B2 receptor antagonist, promotes MC degranulation via MRGPRX2 and causes pseudoallergic drug reaction. Icatibant caused MC degranulation via a pertussis toxin-sensitive G protein but did not activate ß-arrestin. A screen of the National Institutes of Health Clinical Collection library led to the identification of resveratrol as an inhibitor of MRGPRX2. Resveratrol inhibited compound 48/80-induced Tango and MC degranulation in response to compound 48/80, AG-30/5C, and Icatibant. This study demonstrates the novel finding that AG-30/5C and Icatibant serve as G protein-biased agonists for MRGPRX2, but compound 48/80 signals via both G protein and ß-arrestin with distinct differences in receptor regulation.


Assuntos
Antagonistas de Receptor B2 da Bradicinina/farmacologia , Bradicinina/análogos & derivados , Mastócitos/efeitos dos fármacos , Proteínas do Tecido Nervoso/agonistas , Peptídeos/farmacologia , Receptores Acoplados a Proteínas G/agonistas , Receptores de Neuropeptídeos/agonistas , Animais , Bradicinina/farmacologia , Células Cultivadas , Células HEK293 , Humanos , Mastócitos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Ratos , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Neuropeptídeos/metabolismo
3.
J Cell Biochem ; 121(1): 804-815, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31407360

RESUMO

Anticancer drugs exert their effects on cancer cells by deregulating many pathways linked to cell cycle, apoptosis, etc. but cancer cells gradually become resistive against anticancer drugs, thereby necessitating the development of newer generation anticancer molecules. N-end rule pathway has been shown to be involved in the degradation of many cell cycle and apoptosis-related proteins. However, the involvements of this pathway in cancer are not well established. Recently, we developed a non-peptide-based N-end rule pathway inhibitor, RF-C11 for type 1 and 2 recognition domains of E3 ubiquitin ligases. The inhibitor significantly increased the half-life of potential N-degrons leading to significant physiological changes in vivo. We hypothesized RF-C11 may be used to decipher the N-end rule pathway's role in cancer towards the development of anticancer therapeutics. In this study, we showed that RF-C11, barring noncancer cells, significantly sensitizes cancer cells towards different anticancer agents tested. We further find that the profound cellular sensitization to anticancer drugs was affected by (a) downregulation of X-linked inhibitor of apoptosis protein, an antiapoptotic protein and (b) by stabilization of RAD21, and thereby inhibiting metaphase to anaphase promotion. The study shows that RF-C11 or its analogs may be used as a novel additive in combination therapy against cancer.


Assuntos
Antineoplásicos/farmacologia , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Inibidores Enzimáticos/farmacologia , Regulação Neoplásica da Expressão Gênica , Neoplasias/tratamento farmacológico , Ubiquitina-Proteína Ligases/antagonistas & inibidores , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Proteínas de Ciclo Celular/genética , Proliferação de Células , Proteínas de Ligação a DNA/genética , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Células Tumorais Cultivadas , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética
4.
Int J Mol Sci ; 20(21)2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31652731

RESUMO

The neuropeptide substance P (SP) contributes to neurogenic inflammation through the activation of human mast cells via Mas-related G protein-coupled receptor-X2 (MRGPRX2). Using pertussis toxins and YM-254890, we demonstrated that SP induces Ca2+ mobilization and degranulation via both the Gαi and Gαq family of G proteins in rat basophilic leukemia (RBL-2H3) cells stably expressing MRGPRX2. To determine the roles of MRGPRX2's transmembrane (TM) and intracellular domains on SP-induced responses, we utilized information obtained from both structural modeling and naturally occurring MRGPRX2 missense variants. We found that highly conserved residues in TM6 (I225) and TM7 (Y279) of MRGPRX2 are essential for SP-induced Ca2+ mobilization and degranulation in transiently transfected RBL-2H3 cells. Cells expressing missense variants in the receptor's conserved residues (V123F and V282M) as well as intracellular loops (R138C and R141C) failed to respond to SP. By contrast, replacement of all five Ser/Thr residues with Ala and missense variants (S325L and L329Q) in MRGPRX2's carboxyl-terminus resulted in enhanced mast cell activation by SP when compared to the wild-type receptor. These findings suggest that MRGPRX2 utilizes conserved residues in its TM domains and intracellular loops for coupling to G proteins and likely undergoes desensitization via phosphorylation at Ser/Thr residues in its carboxyl-terminus. Furthermore, identification of gain and loss of function MRGPRX2 variants has important clinical implications for SP-mediated neurogenic inflammation and other chronic inflammatory diseases.


Assuntos
Mutação com Ganho de Função , Mutação com Perda de Função , Mastócitos/metabolismo , Proteínas do Tecido Nervoso/química , Receptores Acoplados a Proteínas G/química , Receptores de Neuropeptídeos/química , Substância P/metabolismo , Animais , Cálcio/metabolismo , Linhagem Celular Tumoral , Sequência Conservada , Humanos , Mutação de Sentido Incorreto , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Domínios Proteicos , Ratos , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Neuropeptídeos/genética , Receptores de Neuropeptídeos/metabolismo
5.
Mol Cell Biochem ; 399(1-2): 95-103, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25312902

RESUMO

Oxidative stress in the insulin target tissues has been implicated in the pathophysiology of type 2 diabetes. The study has examined the oxidative stress parameters in the mitochondria of subcutaneous white adipose tissue from obese and non-obese subjects with or without type 2 diabetes. An accumulation of protein carbonyls, fluorescent lipid peroxidation products, and malondialdehyde occurs in the adipose tissue mitochondria of obese type 2 diabetic, non-diabetic obese, and non-obese diabetic subjects with the maximum increase noticed in the obese type 2 diabetes patients and the minimum in non-obese type 2 diabetics. The mitochondria from obese type 2 diabetics, non-diabetic obese, and non-obese type 2 diabetics also produce significantly more reactive oxygen species (ROS) in vitro compared to those of controls, and apparently the mitochondrial ROS production rate in each group is proportional to the respective load of oxidative damage markers. Likewise, the mitochondrial antioxidant enzymes like superoxide dismutase and glutathione peroxidase show decreased activities most markedly in obese type 2 diabetes subjects and to a lesser degree in non-obese type 2 diabetes or non-diabetic obese subjects in comparison to control. The results imply that mitochondrial dysfunction with enhanced ROS production may contribute to the metabolic abnormality of adipose tissue in obesity and diabetes.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Mitocôndrias/metabolismo , Obesidade/metabolismo , Gordura Subcutânea/metabolismo , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Peróxido de Hidrogênio/metabolismo , Masculino , Pessoa de Meia-Idade , Oxirredução , Estresse Oxidativo , Oxirredutases/metabolismo , Gordura Subcutânea/patologia , Superóxido Dismutase/metabolismo
7.
Org Biomol Chem ; 12(11): 1793-803, 2014 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-24514758

RESUMO

An efficient diastereoselective synthesis of brevipolide H derivative is described. The approach features the use of (i) catalytic asymmetric transfer hydrogenation, (ii) hydroxyl-directed cyclopropanation, and (iii) substrate-controlled catalytic epoxidation and ring-closing metathesis. Remarkably, in this convergent synthesis process, stereogenic centers were installed through catalytic reactions with high stereocontrol, which greatly facilitates the synthesis of stereo-divergent derivatives.


Assuntos
Ciclopropanos/síntese química , Ciclopropanos/química , Células HEK293 , Humanos , Lippia/química , Células MCF-7 , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Pironas , Estereoisomerismo
8.
Int Rev Cell Mol Biol ; 386: 167-222, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38782499

RESUMO

Historically, KRAS has been considered 'undruggable' inspite of being one of the most frequently altered oncogenic proteins in solid tumors, primarily due to the paucity of pharmacologically 'druggable' pockets within the mutant isoforms. However, pioneering developments in drug design capable of targeting the mutant KRAS isoforms especially KRASG12C-mutant cancers, have opened the doors for emergence of combination therapies comprising of a plethora of inhibitors targeting different signaling pathways. SHP2 signaling pathway, primarily known for activation of intracellular signaling pathways such as KRAS has come up as a potential target for such combination therapies as it emerged to be the signaling protein connecting KRAS and the immune signaling pathways and providing the link for understanding the overlapping regions of RAS/ERK/MAPK signaling cascade. Thus, SHP2 inhibitors having potent tumoricidal activity as well as role in immunomodulation have generated keen interest in researchers to explore its potential as combination therapy in KRAS mutant solid tumors. However, the excitement with these combination therapies need to overcome challenges thrown up by drug resistance and enhanced toxicity. In this review, we will discuss KRAS and SHP2 signaling pathways and their roles in immunomodulation and regulation of tumor microenvironment and also analyze the positive effects and drawbacks of the different combination therapies targeted at these signaling pathways along with their present and future potential to treat solid tumors.


Assuntos
Imunomodulação , Neoplasias , Proteína Tirosina Fosfatase não Receptora Tipo 11 , Proteínas Proto-Oncogênicas p21(ras) , Transdução de Sinais , Humanos , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/terapia , Transdução de Sinais/efeitos dos fármacos , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Imunomodulação/efeitos dos fármacos , Animais , Resultado do Tratamento , Terapia de Alvo Molecular
9.
Int Rev Cell Mol Biol ; 386: 81-131, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38782502

RESUMO

Autophagy and Unfolded Protein Response (UPR) can be regarded as the safe keepers of cells exposed to intense stress. Autophagy maintains cellular homeostasis, ensuring the removal of foreign particles and misfolded macromolecules from the cytoplasm and facilitating the return of the building blocks into the system. On the other hand, UPR serves as a shock response to prolonged stress, especially Endoplasmic Reticulum Stress (ERS), which also includes the accumulation of misfolded proteins in the ER. Since one of the many effects of viral infection on the host cell machinery is the hijacking of the host translational system, which leaves in its wake a plethora of misfolded proteins in the ER, it is perhaps not surprising that UPR and autophagy are common occurrences in infected cells, tissues, and patient samples. In this book chapter, we try to emphasize how UPR, and autophagy are significant in infections caused by six major oncolytic viruses-Epstein-Barr (EBV), Human Papilloma Virus (HPV), Human Immunodeficiency Virus (HIV), Human Herpesvirus-8 (HHV-8), Human T-cell Lymphotropic Virus (HTLV-1), and Hepatitis B Virus (HBV). Here, we document how whole-virus infection or overexpression of individual viral proteins in vitro and in vivo models can regulate the different branches of UPR and the various stages of macro autophagy. As is true with other viral infections, the relationship is complicated because the same virus (or the viral protein) exerts different effects on UPR and Autophagy. The nature of this response is determined by the cell types, or in some cases, the presence of diverse extracellular stimuli. The vice versa is equally valid, i.e., UPR and autophagy exhibit both anti-tumor and pro-tumor properties based on the cell type and other factors like concentrations of different metabolites. Thus, we have tried to coherently summarize the existing knowledge, the crux of which can hopefully be harnessed to design vaccines and therapies targeted at viral carcinogenesis.


Assuntos
Autofagia , Resposta a Proteínas não Dobradas , Humanos , Carcinogênese/patologia , Carcinogênese/metabolismo , Animais , Estresse do Retículo Endoplasmático
10.
Int Rev Cell Mol Biol ; 385: 211-226, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38663960

RESUMO

Breast cancer (BC) heterogeneity is a key trait of BC tumors with crucial implications on tumorigenesis, diagnosis, and therapeutic modalities. It is influenced by tumor intrinsic features and by the tumor microenvironment (TME) composition of different intra-tumoral regions, which in turn affect cancer progression within patients. In this mini review, we will highlight the mechanisms that generate cancer heterogeneity in BC and how they affect the responses to cancer therapies.


Assuntos
Neoplasias da Mama , Microambiente Tumoral , Humanos , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/terapia , Feminino , Animais
11.
Biology (Basel) ; 12(2)2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36829496

RESUMO

Immune checkpoint blockade (ICB) has emerged as a novel therapeutic tool for cancer therapy in the last decade. Unfortunately, a small number of patients benefit from approved immune checkpoint inhibitors (ICIs). Therefore, multiple studies are being conducted to find new ICIs and combination strategies to improve the current ICIs. In this review, we discuss some approved immune checkpoints, such as PD-L1, PD-1, and CTLA-4, and also highlight newer emerging ICIs. For instance, HLA-E, overexpressed by tumor cells, represents an immune-suppressive feature by binding CD94/NKG2A, on NK and T cells. NKG2A blockade recruits CD8+ T cells and activates NK cells to decrease the tumor burden. NKG2D acts as an NK cell activating receptor that can also be a potential ICI. The adenosine A2A and A2B receptors, CD47-SIRPα, TIM-3, LAG-3, TIGIT, and VISTA are targets that also contribute to cancer immunoresistance and have been considered for clinical trials. Their antitumor immunosuppressive functions can be used to develop blocking antibodies. PARPs, mARTs, and B7-H3 are also other potential targets for immunosuppression. Additionally, miRNA, mRNA, and CRISPR-Cas9-mediated immunotherapeutic approaches are being investigated with great interest. Pre-clinical and clinical studies project these targets as potential immunotherapeutic candidates in different cancer types for their robust antitumor modulation.

12.
Am J Clin Exp Urol ; 11(2): 121-135, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37168943

RESUMO

PURPOSE: To assess whether therapeutic and toxic effects of intravesical lidocaine are determined by coincident serum levels. MATERIAL AND METHODS: Published clinical trials and case studies on instilled lidocaine 1-2% that reported serum lidocaine levels were analyzed using model independent pharmacokinetic equations to compute the absorbed dose fraction (F) for linear regression with the respective dwell times. RESULTS: Rapid absorption of intravesical lidocaine is evinced by the serum levels of 0.16±0.3 mg/L at 5 min in bladder cancer patients coinciding with the rapid onset of pain relief (<5 min) and blood pressure drop (≥10 mm Hg) in spinal cord injured patients. Serum levels at 5 min are raised five-fold by alkalinization for a tertiary amine with pKa of 7.8 and a linear rise in F with longer dwell time (r2 = 0.80; P<0.005) conforms to passive, paracellular diffusion of amphiphilic lidocaine (log P of 1.68) around umbrella cell borders with absorption rate at least five times faster than the terminal elimination rate, and therefore the delay in blood sampling after instillation is unwarranted. A rapid resolution of therapeutic and toxic effects is predicated on the extensive dilution of absorbed lidocaine with a rapid distribution half-life of 3.6 min in body weight dependent Vd - 15 times larger than blood volume, 0.13-4.5 L/kg which necessitates dose adjustment in children. CONCLUSION: Whether rapid absorption of instilled lidocaine is complicated by an equally rapid and extensive dilution in body weight dependent Vd can be resolved by early blood sampling (<30 min) for: evidence-based medicine, avoidance of lidocaine toxicity in children and to educate the evolution of lidocaine solution to gel and devices.

13.
Drugs Aging ; 40(3): 241-261, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36879156

RESUMO

This article provides an overview of the diagnosis and the treatment of lower urinary tract symptoms in older adults complicated by the neurodegenerative changes in the micturition reflex and further confounded by age-related decline in hepatic and renal clearance raising the propensity of adverse drug reactions. The first-line drug treatment for lower urinary tract symptoms, orally administered antimuscarinics, fails to reach the equilibrium dissociation constant of muscarinic receptors even at their maximum plasma concentration and tends to evoke a half-maximal response at a muscarinic receptor occupancy of just 0.206% in the bladder with a minimal difference from exocrine glands, which raises the adverse drug reaction risk. On the contrary, intravesical antimuscarinics are instilled at concentrations 1000-fold higher than the oral maximum plasma concentration and the equilibrium dissociation constant erects a downhill concentration gradient that drives passive diffusion and achieves a mucosal concentration around ten-fold lower than the instilled concentration for a long-lasting occupation of muscarinic receptors in mucosa and sensory nerves. A high local concentration of antimuscarinics in the bladder triggers alternative mechanisms of action and is supposed to engage retrograde transport to nerve cell bodies for neuroplastic changes that underlie a long-lasting therapeutic effect, while an intrinsically lower systemic uptake of the intravesical route lowers the muscarinic receptor occupancy of exocrine glands to lower the adverse drug reaction relative to the oral route. Thus, the traditional pharmacokinetics and pharmacodynamics of oral treatment are upended by intravesical antimuscarinics to generate a dramatic improvement (~ 76%) noted in a meta-analysis of studies enrolling children with neurogenic lower urinary tract symptoms on the primary endpoint of maximum cystometric bladder capacity as well as the secondary endpoints of filling compliance and uninhibited detrusor contractions. The therapeutic success of intravesical multidose oxybutynin solution or oxybutynin entrapped in the polymer for sustained release in the pediatric population bodes well for patients with lower urinary tract symptoms at the other extreme of the age spectrum. Though generally used to predict oral drug absorption, Lipinski's rule of five can also explain the ten-fold lower systemic uptake from the bladder of positively charged trospium over oxybutynin, a tertiary amine. Chemodenervation by an intradetrusor injection of onabotulinumtoxinA is merited for patients with idiopathic overactive bladder discontinuing oral treatment because of a lack of efficacy. However, age-related peripheral neurodegeneration potentiates the adverse drug reaction risk of urinary retention that motivates the quest of liquid instillation, delivering larger fraction of onabotulinumtoxinA to the mucosa as opposed to muscle by an intradetrusor injection can also probe the neurogenic and myogenic predominance of idiopathic overactive bladder. Overall, the treatment paradigm of lower urinary tract symptoms in older adults should be tailored to individual's overall health status and the risk tolerance for adverse drug reactions.


Assuntos
Toxinas Botulínicas Tipo A , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Sintomas do Trato Urinário Inferior , Bexiga Urinária Hiperativa , Idoso , Humanos , Administração Intravesical , Toxinas Botulínicas Tipo A/uso terapêutico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/tratamento farmacológico , Sintomas do Trato Urinário Inferior/tratamento farmacológico , Antagonistas Muscarínicos/efeitos adversos , Receptores Muscarínicos/uso terapêutico , Bexiga Urinária Hiperativa/tratamento farmacológico
14.
Artigo em Inglês | MEDLINE | ID: mdl-36645405

RESUMO

INTRODUCTION: This meta-analysis was conducted to compare the circulating lipocalin-2 levels in polycystic ovary syndrome (PCOS). EVIDENCE ACQUISITION: Relevant studies were retrieved by online database and manual searching. The standardized mean differences (SMDs) with 95% confidence intervals (CIs) were obtained by a random-effects meta-analysis. The subgroup analysis based on the Body Mass Index (BMI) and the homeostasis model assessment-estimated insulin resistance (HOMA-IR) was conducted. Meta-analysis of correlations and meta-regression were performed for the associations of lipocalin-2 with the metabolic and hormonal covariates. The funnel plot analysis was used for publication bias. EVIDENCE SYNTHESIS: The combined effect size including a total of 13 studies showed no significant difference in lipocalin-2 levels between PCOS and control groups. However, the subgroup meta-analysis based on insulin resistance showed a significant difference in the circulatory lipocalin-2 levels in PCOS as compared to controls in both HOMA-IR<3 (SMD=-1.15, Z=2.42, P=0.02) and HOMA-IR>3 subgroups (SMD=0.91, Z=2.43, P=0.02). CONCLUSIONS: There were significant associations of lipocalin-2 with age, BMI, estrogen and hyperandrogenism in PCOS. Lipocalin-2 level alterations in PCOS are associated to insulin resistance. More is the insulin resistance, higher is the lipocalin-2 level in PCOS as compared to controls.

15.
Curr Oncol ; 30(5): 4632-4647, 2023 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-37232808

RESUMO

This review article gives an overview of the current state of the art of bladder cancer imaging and then discusses in depth the scientific and technical merit of a novel imaging approach, tracing its evolution from murine cancer models to cancer patients. While the poor resolution of soft tissue obtained by widely available imaging options such as abdominal sonography and radiation-based CT leaves them only suitable for measuring the gross tumor volume and bladder wall thickening, dynamic contrast-enhanced magnetic resolution imaging (DCE MRI) is demonstrably superior in resolving muscle invasion. However, major barriers still exist in its adoption. Instead of injection for DCE-MRI, intravesical contrast-enhanced MRI (ICE-MRI) instills Gadolinium chelate (Gadobutrol) together with trace amounts of superparamagnetic agents for measurement of tumor volume, depth, and aggressiveness. ICE-MRI leverages leaky tight junctions to accelerate passive paracellular diffusion of Gadobutrol (604.71 Daltons) by treading the paracellular ingress pathway of fluorescein sodium and of mitomycin (<400 Daltons) into bladder tumor. The soaring cost of diagnosis and care of bladder cancer could be mitigated by reducing the use of expensive operating room resources with a potential non-surgical imaging option for cancer surveillance, thereby reducing over-diagnosis and over-treatment and increasing organ preservation.


Assuntos
Compostos Organometálicos , Neoplasias da Bexiga Urinária , Humanos , Animais , Camundongos , Estadiamento de Neoplasias , Imageamento por Ressonância Magnética/métodos , Neoplasias da Bexiga Urinária/diagnóstico por imagem
16.
Virol J ; 9: 3, 2012 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-22217077

RESUMO

BACKGROUND: Influenza A virus encodes for eleven proteins, of which HA, NA, NS1 and PB1-F2 have been implicated in viral pathogenicity and virulence. Thus, in addition to the HA and NA gene segments, monitoring diversity of NS1 and PB1-F2 is also important. METHODS: 55 out of 166 circulating influenza A strains (31 H1N1 and 24 H3N2) were randomly picked during 2007-2009 and NS and PB1-F2 genes were sequenced. Phylogenetic analysis was carried out with reference to the prototype strains, concurrent vaccine strains and other reference strains isolated world wide. RESULTS: Comparative analysis of both nucleotide and deduced amino acid sequences, revealed presence of NS gene with A/PR/8/34(H1N1)-like mutations (H4N, Q21R, A22V, K44R, N53D, C59R, V60A, F103S and M106I) in both RNA-binding and effector domain of NS1 protein, and G63E, the HPAI-H5N1-like mutation in NEP/NS2 of five A/H1N1 strains of 2007 and 2009. NS1 of other A/H1N1 strains clustered with concurrent A/H1N1 vaccine strains. Of 31 A/H1N1 strains, five had PB1-F2 similar to the H3N2 strains; six had non-functional PB1-F2 protein (11 amino acids) similar to the 2009 pandemic H1N1 strains and rest 20 strains had 57 amino acids PB1-F2 protein, similar to concurrent A/H1N1 vaccine strain. Interestingly, three A/H1N1 strains with H3N2-like PB1-F2 protein carried primitive PR8-like NS gene. Full gene sequencing of PB1 gene confirmed presence of H3N2-like PB1 gene in these A/H1N1 strains. CONCLUSION: Overall the study highlights reassortment event involving gene segments other than HA and NA in the co-circulating A/H1N1 and A/H3N2 strains and their importance in complexity of influenza virus genetics. In contrast, NS and PB1-F2 genes of all A/H3N2 eastern India strains were highly conserved and homologous to the concurrent A/H3N2 vaccine strains suggesting that these gene segments of H3N2 viruses are evolutionarily more stable compared to H1N1 viruses.


Assuntos
Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Influenza Humana/virologia , Vírus Reordenados/isolamento & purificação , Proteínas não Estruturais Virais/genética , Proteínas Virais/genética , Sequência de Aminoácidos , Sequência de Bases , Análise por Conglomerados , Humanos , Índia , Vírus da Influenza A Subtipo H1N1/classificação , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H3N2/classificação , Vírus da Influenza A Subtipo H3N2/genética , Dados de Sequência Molecular , Nariz/virologia , Faringe/virologia , Filogenia , RNA Viral/genética , Vírus Reordenados/classificação , Vírus Reordenados/genética , Análise de Sequência de DNA
17.
Org Lett ; 24(26): 4804-4809, 2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35758604

RESUMO

The hydrogen borrowing strategy is an economical method for the α-functionalization of ketones. While this strategy is extremely advantageous, it does not lend itself to the synthesis of ß,ß-disubstituted ketones. This can be achieved, if the in situ generated metal hydride can be intercepted with a nucleophilic coupling partner. We present a multicomponent strategy for the coupling of alcohols, ketones, and boronic acids using only 1 mol % nickel catalyst and without the need for added ligands.

18.
IFAC Pap OnLine ; 55(10): 1307-1312, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-38620785

RESUMO

The COVID-19 pandemic has shown that stock outs of essential items like hand sanitizers, tissue papers and other items of hygiene and daily use have been characteristic of a supply chain, especially immediately following a pandemic wave. Consequently, retailers have to indulge in substantial supplier management efforts to ensure product availability during a pandemic wave. Using a piecewise deterministic differential game, we model a scenario where, while anticipating a pandemic wave, a supplier decides on product availability efforts to ensure product availability under the impending threat of stock outs. A market leader coordinating retailer, on the other hand, decides on the proportion of the costs of the efforts to be shared with the supplier.

19.
J Food Biochem ; 46(10): e14282, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35735162

RESUMO

In recent years, the application of phytochemicals to prevent or treat diseases has received greater attention. These phytochemicals have little or no toxicity against healthy tissues and are thus considered as ideal compounds. An impressive number of modern drugs are obtained from natural sources based on their traditional value. D-Pinitol is a natural compound that is derived from soy and soy products. It is a potentially active molecule that belongs to the class of inositols. D-pinitol has been pharmacologically evaluated for its potent antioxidant, anti-diabetic, anti-inflammatory, anti-cancer, hepatoprotective, cardioprotective, renoprotective, neuroprotective, immunosuppressive, and anti-osteoporotic efficacies. This review is an attempt to validate the plausible pharmacological effects of D-pinitol using various in vivo and in vitro studies. PRACTICAL IMPLICATIONS: The consumption of plant-based products has been significantly increased all over the world. The active phytochemicals that are found in plants are stated to have numerous health promoting functions for the treatment of diabetes, cancer, inflammation, cardiac diseases, liver dysfunction, and many other. D-Pinitol is abundantly present in soybeans that possess notable therapeutic activities. Understanding the effects of D-Pinitol would potentially help in applying this compound in clinical research for the treatment of different disorders.


Assuntos
Antioxidantes , Fabaceae , Anti-Inflamatórios/farmacologia , Inositol/análogos & derivados , Inositol/farmacologia , Compostos Fitoquímicos , Glycine max/química
20.
Org Lett ; 23(14): 5389-5393, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34170145

RESUMO

Catalyst controlled site-selective C-H functionalization is a challenging but powerful tool in organic synthesis. Polarity-matched and sterically controlled hydrogen atom transfer (HAT) provides an excellent opportunity for site-selective functionalization. As such, the dual Ni/photoredox system was successfully employed to generate acyl radicals from aldehydes via selective formyl C-H activation and subsequently cross-coupled to generate ketones, a ubiquitous structural motif present in the vast majority of natural and bioactive molecules. However, only a handful of examples that are constrained to the use of aryl halides are developed. Given the wide availability of amines, we developed a cross-coupling reaction via C-N bond cleavage using the economic nickel and TBADT catalyst for the first time. A range of alkyl and aryl aldehydes were cross-coupled with benzylic and allylic pyridinium salts to afford ketones with a broad spectrum of functional group tolerance. High regioselectivity toward formyl C-H bonds even in the presence of α-methylene carbonyl or α-amino/oxy methylene was obtained.

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