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1.
J Pathol ; 259(1): 46-55, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36214539

RESUMO

Macrophage migration inhibitory factor (MIF1) is a pleiotropic cytokine involved in inflammation and cancer. Genetic knockout of Mif1 in the validated N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) model of bladder cancer (BCa) resulted in stage arrest at non-muscle-invasive disease in prior studies. Small-molecule inhibition of MIF1 reduced cancer-associated outcomes, but it did not fully recapitulate genetic models. D-dopachrome tautomerase (gene symbol DDT), commonly referred to as MIF2, is a functional homolog of MIF1, and both MIF1 and MIF2 can bind the cell surface receptor CD74 on multiple cell types to initiate a signaling cascade. It has been proposed that this interaction mediates part of the protumorigenic effects of MIF1 and MIF2 and may explain the discordance in prior studies. We hypothesized that MIF2 functions redundantly with MIF1 in BCa development and progression. The Cancer Genome Atlas (TCGA) analysis indicated MIF and DDT expression were increased in BCa patients compared to control. 4-Iodopyridine (4-IPP), a combined MIF1/MIF2 inhibitor, was more efficacious than ISO-1, a MIF1-only inhibitor, in preventing cellular proliferation in BCa cell lines. To evaluate these findings in vivo, wild-type (WT) and Mif1-/- animals were exposed to 0.05% BBN in drinking water for 16 weeks to initiate tumorigenesis and then evaluated over the subsequent 4 weeks for tumor formation and progression in the presence or absence of 4-IPP. 4-IPP reduced bladder weights in WT animals and bladder weights/tumor stage in Mif1-/- animals. To determine whether MIF1/MIF2 functioned through CD74 in BCa, WT or Cd74-/- animals were used in the same BBN model. Although these animals were partially protected against BBN-induced BCa, 4-IPP did not enhance this effect. In conclusion, our data suggest that MIF2 mechanistically functions in a similar protumorigenic manner to MIF1, and this is at least partially through CD74. Dual inhibition of MIF homologs is more efficacious at reducing tumor burden in this model of BCa. © 2022 The Pathological Society of Great Britain and Ireland.


Assuntos
Fatores Inibidores da Migração de Macrófagos , Neoplasias da Bexiga Urinária , Animais , Fatores Inibidores da Migração de Macrófagos/genética , Fatores Inibidores da Migração de Macrófagos/metabolismo , DDT , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Proliferação de Células , Transdução de Sinais
2.
J Chem Inf Model ; 63(9): 2866-2880, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-37058135

RESUMO

SARS-CoV-2 is the causative agent of COVID-19 and is responsible for the current global pandemic. The viral genome contains 5 major open reading frames of which the largest ORF1ab codes for two polyproteins, pp1ab and pp1a, which are subsequently cleaved into 16 nonstructural proteins (nsp) by two viral cysteine proteases encoded within the polyproteins. The main protease (Mpro, nsp5) cleaves the majority of the nsp's, making it essential for viral replication and has been successfully targeted for the development of antivirals. The first oral Mpro inhibitor, nirmatrelvir, was approved for treatment of COVID-19 in late December 2021 in combination with ritonavir as Paxlovid. Increasing the arsenal of antivirals and development of protease inhibitors and other antivirals with a varied mode of action remains a priority to reduce the likelihood for resistance emerging. Here, we report results from an artificial intelligence-driven approach followed by in vitro validation, allowing the identification of five fragment-like Mpro inhibitors with IC50 values ranging from 1.5 to 241 µM. The three most potent molecules (compounds 818, 737, and 183) were tested against SARS-CoV-2 by in vitro replication in Vero E6 and Calu-3 cells. Compound 818 was active in both cell models with an EC50 value comparable to its measured IC50 value. On the other hand, compounds 737 and 183 were only active in Calu-3, a preclinical model of respiratory cells, showing selective indexes twice as high as those for compound 818. We also show that our in silico methodology was successful in identifying both reversible and covalent inhibitors. For instance, compound 818 is a reversible chloromethylamide analogue of 8-methyl-γ-carboline, while compound 737 is an N-pyridyl-isatin that covalently inhibits Mpro. Given the small molecular weights of these fragments, their high binding efficiency in vitro and efficacy in blocking viral replication, these compounds represent good starting points for the development of potent lead molecules targeting the Mpro of SARS-CoV-2.


Assuntos
Antivirais , COVID-19 , Humanos , Antivirais/farmacologia , Antivirais/química , SARS-CoV-2 , Inteligência Artificial , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , Simulação de Acoplamento Molecular
3.
Glob Chang Biol ; 23(6): 2250-2261, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28231634

RESUMO

Invasive species are a significant threat to global biodiversity, but our understanding of how invasive species impact native communities across space and time remains limited. Based on observations in an old field in Southeast Michigan spanning 35 years, our study documents significant impacts of habitat change, likely driven by the invasion of the shrub, Elaeagnus umbellata, on the nest distribution patterns and population demographics of a native ant species, Formica obscuripes. Landcover change in aerial photographs indicates that E. umbellata expanded aggressively, transforming a large proportion of the original open field into dense shrubland. By comparing the ant's landcover preferences before and after the invasion, we demonstrate that this species experienced a significant unfavorable change in its foraging areas. We also find that shrub landcover significantly moderates aggression between nests, suggesting nests are more related where there is more E. umbellata. This may represent a shift in reproductive strategy from queen flights, reported in the past, to asexual nest budding. Our results suggest that E. umbellata may affect the spatial distribution of F. obscuripes by shifting the drivers of nest pattern formation from an endogenous process (queen flights), which led to a uniform pattern, to a process that is both endogenous (nest budding) and exogenous (loss of preferred habitat), resulting in a significantly different clustered pattern. The number and sizes of F. obscuripes nests in our study site are projected to decrease in the next 40 years, although further study of this population's colony structures is needed to understand the extent of this decrease. Elaeagnus umbellata is a common invasive shrub, and similar impacts on native species might occur in its invasive range, or in areas with similar shrub invasions.


Assuntos
Formigas , Ecossistema , Espécies Introduzidas , Plantas , Animais , Michigan
4.
Cancers (Basel) ; 15(6)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36980540

RESUMO

Pyruvate dehydrogenase kinase 4 (PDK4) is a mitochondrial isozyme in the PDK family (PDK1-4) partially responsible for phosphorylation of pyruvate dehydrogenase (PDH). Phosphorylation of PDH is thought to result in a pro-proliferative shift in metabolism that sustains growth of cancer cells. Previous data from our lab indicate the pan-PDK inhibitor dichloroacetate (DCA) or acute genetic knockdown of PDK4 blocks proliferation of bladder cancer (BCa) cells. The goal of this study was to determine the role of PDK4 in an in vivo BCa model, with the hypothesis that genetic depletion of PDK4 would impair formation of BCa. PDK4-/- or WT animals were exposed to N-Butyl-N-(4-hydroxybutyl) nitrosamine (BBN) for 16 weeks, and tumors were allowed to develop for up to 7 additional weeks. PDK4-/- mice had significantly larger tumors at later time points. When animals were treated with cisplatin, PDK4-/- animals still had larger tumors than WT mice. PDK4 expression was assessed in human tissue and in mice. WT mice lost expression of PDK4 as tumors became muscle-invasive. Similar results were observed in human samples, wherein tumors had less expression of PDK4 than benign tissue. In summary, PDK4 has a complex, multifunctional role in BCa and may represent an underrecognized tumor suppressor.

5.
Nat Rev Urol ; 19(8): 495-509, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35798831

RESUMO

Ageing is correlated with elevated bladder cancer incidence, morbidity and mortality. Advanced age is also associated with elevated markers of chronic inflammation and perturbations in gut and urinary tract microbiota. One reason for the increased incidence and mortality of bladder cancer in the elderly might be that age-associated changes in multiple microbiomes induce systemic metabolic changes that contribute to immune dysregulation with potentially tumorigenic effects. The gut and urinary microbiomes could be dysregulated in bladder cancer, although the effect of these changes is poorly understood. Each of these domains - the immune system, gut microbiome and urinary microbiome - might also influence the response of patients with bladder cancer to treatment. Improved understanding of age-related alterations to the immune system and gut and urinary microbiomes could provide possible insight into the risk of bladder cancer development and progression in the elderly. In patients with bladder cancer, improved understanding of microbiota might also provide potential targets for therapeutic intervention.


Assuntos
Microbioma Gastrointestinal , Microbiota , Neoplasias da Bexiga Urinária , Idoso , Envelhecimento , Humanos , Sistema Imunitário
6.
Urology ; 149: 187-192, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33412223

RESUMO

OBJECTIVE: To determine if MOSES technology improves efficiency and short-term outcomes in holmium laser ablation of the prostate (HoLAP). METHODS: A retrospective review of patients who underwent HoLAP between August 2016 and November 2019 was conducted. All procedures before and after the implementation of MOSES technology at our institution were evaluated. Preoperative patient characteristics and intraoperative data were collected. Postoperative International Prostate Symptom Score, quality of life, and postvoid residual measurements at 6 weeks and 3 months postoperatively were analyzed. RESULTS: This cohort included 65 males who underwent HoLAP, 32 without and 33 with MOSES. Patients in the MOSES group were slightly older, but no other differences in baseline characteristics were observed between the two groups. Ablation time was similar at 49.6 ± 26.1 minutes without and 40.7 ± 41.2 minutes with MOSES (P = .38). However, HoLAP with MOSES had significantly higher ablation efficiency (0.59 ± 0.24 g/min without vs 0.86 0.5 g/min with MOSES, P = .01). On multivariable regression modeling, HoLAP without MOSES added 12 minutes to operating time (estimate 12.3, standard error 3.44, P < .01) after controlling for prostate size and laser energy usage. Duration of catheterization, urinary incontinence and need for reoperation within 3 months were similar. There were no differences between groups in International Prostate Symptom Score, quality of life, or postvoid residual at 3 months postoperatively. CONCLUSION: Utilization of MOSES technology resulted in improved efficiency in HoLAP, translating into time savings in the operating room. Postoperative outcomes out to 3 months were similar among patients who underwent the procedure utilizing either laser pulse mode. Further studies are needed to investigate long-term outcomes as the use of MOSES is likely to become more commonly utilized.


Assuntos
Terapia a Laser/métodos , Lasers de Estado Sólido/uso terapêutico , Sintomas do Trato Urinário Inferior/cirurgia , Prostatectomia/métodos , Hiperplasia Prostática/cirurgia , Idoso , Humanos , Terapia a Laser/instrumentação , Terapia a Laser/estatística & dados numéricos , Sintomas do Trato Urinário Inferior/etiologia , Sintomas do Trato Urinário Inferior/psicologia , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Próstata/patologia , Próstata/cirurgia , Prostatectomia/instrumentação , Prostatectomia/estatística & dados numéricos , Hiperplasia Prostática/complicações , Hiperplasia Prostática/patologia , Qualidade de Vida , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Resultado do Tratamento
7.
ISME Commun ; 1(1): 80, 2021 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-37938270

RESUMO

Autism Spectrum Disorder (ASD) is a complex neurodevelopmental disorder influenced by both genetic and environmental factors. Recently, gut dysbiosis has emerged as a powerful contributor to ASD symptoms. In this study, we recruited over 100 age-matched sibling pairs (between 2 and 8 years old) where one had an Autism ASD diagnosis and the other was developing typically (TD) (432 samples total). We collected stool samples over four weeks, tracked over 100 lifestyle and dietary variables, and surveyed behavior measures related to ASD symptoms. We identified 117 amplicon sequencing variants (ASVs) that were significantly different in abundance between sibling pairs across all three timepoints, 11 of which were supported by at least two contrast methods. We additionally identified dietary and lifestyle variables that differ significantly between cohorts, and further linked those variables to the ASVs they statistically relate to. Overall, dietary and lifestyle features were explanatory of ASD phenotype using logistic regression, however, global compositional microbiome features were not. Leveraging our longitudinal behavior questionnaires, we additionally identified 11 ASVs associated with changes in reported anxiety over time within and across all individuals. Lastly, we find that overall microbiome composition (beta-diversity) is associated with specific ASD-related behavioral characteristics.

8.
Acta Crystallogr F Struct Biol Commun ; 73(Pt 1): 54-61, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28045395

RESUMO

Streptococcus pneumoniae is an opportunistic respiratory pathogen that remains a major cause of morbidity and mortality globally, with infants and the elderly at the highest risk. S. pneumoniae relies entirely on carbohydrates as a source of carbon and dedicates a third of all uptake systems to carbohydrate import. The structure of the carbohydrate-free substrate-binding protein SP0092 at 1.61 Šresolution reveals it to belong to the newly proposed subclass G of substrate-binding proteins, with a ligand-binding pocket that is large enough to accommodate complex oligosaccharides. SP0092 is a dimer in solution and the crystal structure reveals a domain-swapped dimer with the monomer subunits in a closed conformation but in the absence of carbohydrate ligand. This closed conformation may be induced by dimer formation and could be used as a mechanism to regulate carbohydrate uptake.


Assuntos
Proteínas de Bactérias/química , Oligossacarídeos/química , Receptores de Superfície Celular/química , Streptococcus pneumoniae/química , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Clonagem Molecular , Cristalografia por Raios X , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Modelos Moleculares , Oligossacarídeos/metabolismo , Plasmídeos/química , Plasmídeos/metabolismo , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Streptococcus pneumoniae/metabolismo , Especificidade por Substrato
9.
J Int Soc Sports Nutr ; 14: 46, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29209154

RESUMO

BACKGROUND: Pre-workout supplements purportedly enhance feelings of energy, reduce fatigue and improve exercise performance. The purpose of this study was to examine the performance effects of caffeinated and non-caffeinated multi-ingredient pre-workout supplements. METHODS: In a counterbalanced, double-blind, placebo-controlled design, eccentric and concentric force production during lower body resistance exercise on a mechanized squat device were assessed after supplement ingestion. Repetitions-in-reserve/RPE and subjective feelings of energy, focus and fatigue were also examined. Twenty-one resistance-trained adults (12 F, 9 M) completed three conditions in random order: caffeinated supplement, non-caffeinated supplement and placebo. Subjects were not informed of the presence of a placebo condition. Thirty minutes after supplement ingestion, a 3-repetition maximum test and 5 sets of 6 repetitions were completed using the squat device. Each repetition involved 4-s eccentric and concentric phases, and the force signal throughout each repetition was sampled from a load cell contained within the squat device. The scaled and filtered force signals were analyzed using customized software. Repeated measures analysis of variance and appropriate follow-up analyses were utilized to compare dependent variables, and relevant effect sizes (d) were calculated. RESULTS: Supplement or placebo ingestion led to similar subjective responses (p > 0.05). Energy (+8 to 44%; d = 0.3 to 0.8) and focus (+8 to 25%; d = 0.3 to 0.5) were acutely increased by supplement or placebo ingestion and decreased as the exercise session progressed. Fatigue was acutely decreased by supplement or placebo ingestion (-7 to 38%; d = -0.1 to -0.6) and increased as the exercise session progressed. Eccentric and concentric forces were unimproved by supplementation during the exercise sets for both sexes. In the non-caffeinated supplement condition only, maximal eccentric force production was lower during sets 3 to 5, as compared to set 1 (p < 0.05). Effect size data indicated that both the caffeinated and non-caffeinated supplements may contribute to small increases in concentric force production in males (+5 to 20%, d = 0.2 to 0.4 relative to placebo), but not females. CONCLUSIONS: As compared to placebo, caffeinated and non-caffeinated multi-ingredient pre-workout supplements failed to improve concentric and eccentric force production. In males, effect size data indicate a possible small benefit of supplementation on concentric force production, although this was not statistically significant. When resistance-trained subjects were unaware of the presence of a placebo, resistance exercise performance was similar regardless of whether a placebo or multi-ingredient supplement was ingested.


Assuntos
Cafeína/farmacologia , Suplementos Nutricionais , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiologia , Treinamento Resistido , Análise de Variância , Método Duplo-Cego , Fadiga , Feminino , Alimentos Formulados , Humanos , Masculino , Resistência Física/efeitos dos fármacos , Resistência Física/fisiologia , Fatores Sexuais , Fenômenos Fisiológicos da Nutrição Esportiva , Adulto Jovem
10.
J Appl Crystallogr ; 47(Pt 5): 1781-1783, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25294981

RESUMO

The macromolecular crystallography (MX) user experience at synchrotron radiation facilities continues to evolve, with the impact of developments in X-ray detectors, computer hardware and automation methods making it possible for complete data sets to be collected on timescales of tens of seconds. Data can be reduced in a couple of minutes and in favourable cases structures solved and refined shortly after. The information-rich database ISPyB, automatically populated by data acquisition software, data processing and structure solution pipelines at the Diamond Light Source beamlines, allows users to automatically track MX experiments in real time. In order to improve the synchrotron users' experience, efficient access to the data contained in ISPyB is now provided via an iOS 6.0+ app for iPhones and iPads. This provides users, both local and remote, with a succinct summary of data collection, visualization of diffraction images and crystals, and key metrics for data quality in real time.

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