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1.
PLoS Genet ; 20(8): e1011360, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39172766

RESUMO

Secondary contact between closely related taxa represents a "moment of truth" for speciation-an opportunity to test the efficacy of reproductive isolation that evolved in allopatry and to identify the genetic, behavioral, and/or ecological barriers that separate species in sympatry. Sex chromosomes are known to rapidly accumulate differences between species, an effect that may be exacerbated for neo-sex chromosomes that are transitioning from autosomal to sex-specific inheritance. Here we report that, in the Solomon Islands, two closely related bird species in the honeyeater family-Myzomela cardinalis and Myzomela tristrami-carry neo-sex chromosomes and have come into recent secondary contact after ~1.1 my of geographic isolation. Hybrids of the two species were first observed in sympatry ~100 years ago. To determine the genetic consequences of hybridization, we use population genomic analyses of individuals sampled in allopatry and in sympatry to characterize gene flow in the contact zone. Using genome-wide estimates of diversity, differentiation, and divergence, we find that the degree and direction of introgression varies dramatically across the genome. For sympatric birds, autosomal introgression is bidirectional, with phenotypic hybrids and phenotypic parentals of both species showing admixed ancestry. In other regions of the genome, however, the story is different. While introgression on the Z/neo-Z-linked sequence is limited, introgression of W/neo-W regions and mitochondrial sequence (mtDNA) is highly asymmetric, moving only from the invading M. cardinalis to the resident M. tristrami. The recent hybridization between these species has thus enabled gene flow in some genomic regions but the interaction of admixture, asymmetric mate choice, and/or natural selection has led to the variation in the amount and direction of gene flow at sex-linked regions of the genome.


Assuntos
Fluxo Gênico , Introgressão Genética , Hibridização Genética , Isolamento Reprodutivo , Cromossomos Sexuais , Animais , Cromossomos Sexuais/genética , Especiação Genética , Simpatria , Masculino , Feminino , Aves/genética , Melanesia , Genética Populacional , Genoma/genética
2.
Nucleic Acids Res ; 51(16): 8383-8401, 2023 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-37526283

RESUMO

Gene functional descriptions offer a crucial line of evidence for candidate genes underlying trait variation. Conversely, plant responses to environmental cues represent important resources to decipher gene function and subsequently provide molecular targets for plant improvement through gene editing. However, biological roles of large proportions of genes across the plant phylogeny are poorly annotated. Here we describe the Joint Genome Institute (JGI) Plant Gene Atlas, an updateable data resource consisting of transcript abundance assays spanning 18 diverse species. To integrate across these diverse genotypes, we analyzed expression profiles, built gene clusters that exhibited tissue/condition specific expression, and tested for transcriptional response to environmental queues. We discovered extensive phylogenetically constrained and condition-specific expression profiles for genes without any previously documented functional annotation. Such conserved expression patterns and tightly co-expressed gene clusters let us assign expression derived additional biological information to 64 495 genes with otherwise unknown functions. The ever-expanding Gene Atlas resource is available at JGI Plant Gene Atlas (https://plantgeneatlas.jgi.doe.gov) and Phytozome (https://phytozome.jgi.doe.gov/), providing bulk access to data and user-specified queries of gene sets. Combined, these web interfaces let users access differentially expressed genes, track orthologs across the Gene Atlas plants, graphically represent co-expressed genes, and visualize gene ontology and pathway enrichments.


Assuntos
Genes de Plantas , Transcriptoma , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Filogenia , Software , Transcriptoma/genética , Atlas como Assunto
3.
Cell Commun Signal ; 22(1): 30, 2024 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-38212807

RESUMO

Glioblastoma is the most common and aggressive primary brain tumour in adults. The development of anti-brain cancer agents are challenged by the blood-brain barrier and the resistance conferred by the local tumour microenvironment. Heptamethine cyanine dyes (HMCDs) are a class of near-infrared fluorescence compounds that have recently emerged as promising agents for drug delivery. We conjugated palbociclib, a cyclin-dependent kinase (CDK) 4/6 inhibitor, to an HMCD, MHI-148, and conducted drug activity analysis on primary patient-derived glioblastoma cell lines. In addition to the expected cytostatic activity, our in vitro studies revealed that palbociclib-MHI-148 conjugate resulted in an almost 100-fold increase in cytotoxicity compared to palbociclib alone. This shift of palbociclib from cytostatic to cytotoxic when conjugated to MHI-148 was due to increased DNA damage, as indicated by an increase in γH2AX foci, followed by an increased expression of key extrinsic apoptosis genes, including TP53, TNFR1, TRAIL, FADD and caspase 8. In addition, we observed a time-dependent increase in the cell surface expression of TNFR1, consistent with an observed increase in the secretion TNFα, followed by TNFR1 endocytosis at 48 h. The treatment of patient GBM cells with the palbociclib-MHI-148 conjugate prevented TNFα-induced NFκB translocation, suggesting conjugate-induced TNFR1 signalling favoured the TNFR1-mediated apoptotic response rather than the pro-inflammatory response pathway. Notably, pharmacological inhibition of endocytosis of TNFR1, and siRNA-knockdown of TNFR1 reversed the palbociclib-MHI-148-induced cell death. These results show a novel susceptibility of glioblastoma cells to TNFR1-dependent apoptosis, dependent on inhibition of canonical NFκB signalling using our previously reported palbociclib-HMCD conjugate. Video Abstract.


Assuntos
Antineoplásicos , Carbocianinas , Citostáticos , Glioblastoma , Indóis , Piperazinas , Piridinas , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Linhagem Celular Tumoral , Citostáticos/farmacologia , Citostáticos/uso terapêutico , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Receptores do Fator de Necrose Tumoral/fisiologia , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Microambiente Tumoral , Fator de Necrose Tumoral alfa/metabolismo
4.
Mycoses ; 67(7): e13768, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39036952

RESUMO

BACKGROUND: There is a concerning rise in antifungal-resistant dermatophytosis globally, with resistance to terbinafine conferred by point mutations in the squalene epoxidase (SQLE) gene. OBJECTIVES: Report changes in the prevalence and profile of SQLE mutations in onychomycosis patients in the United States. METHODS: A longitudinal cohort study of toenail samples was collected from suspected onychomycosis patients over an 18-month period from 2022 to 2023. Samples were submitted from across the United States and subjected to multiplex real-time polymerase chain reactions for dermatophyte detection, with further screening of SQLE mutations at four known hotspots (393Leu, 397Phe, 415Phe and 440His). RESULTS: A total of 62,056 samples were submitted (mean age: 57.5 years; female: 60.4%). Dermatophytes were detected in 38.5% of samples, primarily Trichophyton rubrum complex (83.6%) and T. mentagrophytes complex (10.7%). A survey of SQLE mutations was carried out in 22,610 dermatophyte samples; there was a significant increase in the prevalence of SQLE mutations between the first quarter of 2022 and the second quarter of 2023 (29.0 to 61.9 per 1000 persons). The Phe397Leu substitution was the predominant mutation; Phe415Ser and His440Tyr have also emerged which were previously reported as minor mutations in skin samples. The temporal change in mutation rates can be primarily attributed to the Phe415Ser substitution. Samples from elderly patients (>70 years) are more likely to be infected with the T. mentagrophytes complex including strains harbouring the Phe415Ser substitution. CONCLUSION: The prevalence of SQLE mutations among onychomycosis patients with Trichophyton infections may be underestimated. Older individuals may have a higher risk.


Assuntos
Antifúngicos , Arthrodermataceae , Farmacorresistência Fúngica , Onicomicose , Esqualeno Mono-Oxigenase , Terbinafina , Humanos , Onicomicose/microbiologia , Onicomicose/epidemiologia , Onicomicose/tratamento farmacológico , Esqualeno Mono-Oxigenase/genética , Feminino , Pessoa de Meia-Idade , Masculino , Terbinafina/farmacologia , Terbinafina/uso terapêutico , Farmacorresistência Fúngica/genética , Estados Unidos/epidemiologia , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Estudos Longitudinais , Idoso , Arthrodermataceae/genética , Arthrodermataceae/efeitos dos fármacos , Adulto , Mutação , Estudos de Coortes , Trichophyton/genética , Trichophyton/efeitos dos fármacos , Adulto Jovem , Prevalência , Mutação Puntual , Idoso de 80 Anos ou mais , Adolescente , Unhas/microbiologia
5.
J Eur Acad Dermatol Venereol ; 38(3): 480-495, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38010049

RESUMO

Nondermatophyte moulds (NDMs) are widely distributed and can be detected in association with mycotic nails; however, sometimes it can be challenging to establish the role of NDMs in the pathogenesis of onychomycosis (i.e. causative vs. contaminant). In studies where the ongoing invasive presence of NDMs is confirmed through repeat cultures, the global prevalence of NDMs in onychomycosis patients is estimated at 6.9% with the 3 most common genus being: Aspergillus, Scopulariopsis and Fusarium. NDM onychomycosis can, in many cases, appear clinically indistinguishable from dermatophyte onychomycosis. Clinical features suggestive of NDMs include proximal subungual onychomycosis with paronychia associated with Aspergillus spp., Fusarium spp. and Scopulariopsis brevicaulis, as well as superficial white onychomycosis in a deep and diffused pattern associated with Aspergillus and Fusarium. Longitudinal streaks seen in patients with distal and lateral onychomycosis may serve as an additional indicator. For diagnosis, light microscopic examination should demonstrate fungal filaments consistent with an NDM with at least two independent isolations in the absence of a dermatophyte; the advent of molecular testing combined with histological assessment may serve as an alternative with improved sensitivity and turnover time. In most instances, antifungal susceptibility testing has limited value. Information on effective treatments for NDM onychomycosis is relatively scarce, unlike the situation in the study of dermatophyte onychomycosis. Terbinafine and itraconazole therapy (continuous and pulsed) appear effective to varying extents for treating onychomycosis caused by Aspergillus, Fusarium or Scopulariopsis. There is scant literature on oral treatments for Neoscytalidium.


Assuntos
Onicomicose , Paroniquia , Humanos , Onicomicose/diagnóstico , Onicomicose/tratamento farmacológico , Onicomicose/epidemiologia , Terbinafina/uso terapêutico , Itraconazol/uso terapêutico , Resultado do Tratamento
6.
BMC Bioinformatics ; 24(1): 317, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37608271

RESUMO

BACKGROUND: Transposable elements (TEs) are short, mobile DNA elements that are known to play important roles in the genomes of many eukaryotic species. The identification and categorization of these elements is a critical task for many genomic studies, and the continued increase in the number of de novo assembled genomes demands new tools to improve the efficiency of this process. For this reason, we developed RepBox, a suite of Python scripts that combine several pre-existing family-specific TE detection methods into a single user-friendly pipeline. RESULTS: Based on comparisons of RepBox with the standard TE detection software RepeatModeler, we find that RepBox consistently classifies more elements and is also able to identify a more diverse array of TE families than the existing methods in plant genomes. CONCLUSIONS: The performance of RepBox on two different plant genomes indicates that our toolbox represents a significant improvement over existing TE detection methods, and should facilitate future TE annotation efforts in additional species.


Assuntos
Elementos de DNA Transponíveis , Eucariotos , Humanos , Elementos de DNA Transponíveis/genética , Células Eucarióticas , Genoma de Planta , Genômica
7.
Value Health ; 26(9): 1334-1344, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37187234

RESUMO

OBJECTIVES: This study aimed to evaluate the real-world impacts of a chronic obstructive pulmonary disease (COPD) care pathway program on healthcare utilization and costs in Saskatchewan, Canada. METHODS: A difference-in-differences evaluation of a real-life deployment of a COPD care pathway, using patient-level administrative health data in Saskatchewan, was conducted. The intervention group (n = 759) included adults (35+ years) with spirometry-confirmed COPD diagnosis recruited into the care pathway program in Regina between April 1, 2018 and March 31, 2019. The 2 control groups comprised adults (35+ years) with COPD who lived in Saskatoon during the same period (n = 759) or Regina between April 1, 2015 and March 31, 2016 (n = 759) who did not participate in the care pathway. RESULTS: Compared with the individuals in the Saskatoon control groups, individuals in the COPD care pathway group had shorter inpatient hospital length of stay (average treatment effect on the treated [ATT] -0.46, 95% CI -0.88 to -0.04) but a higher number of general practitioner visits (ATT 1.46, 95% CI 1.14 to 1.79) and specialist physician visits (ATT 0.84, 95% CI 0.61 to 1.07). Regarding healthcare costs, individuals in the care pathway group had higher COPD-related specialist visit costs (ATT $81.70, 95% CI $59.45 to $103.96) but lower COPD-related outpatient drug dispensation costs (ATT -$4.81, 95% CI -$9.34 to -$0.27). CONCLUSIONS: The care pathway reduced inpatient hospital length of stay, but increased general practitioner and specialist physician visits for COPD-related services within the first year of implementation.


Assuntos
Procedimentos Clínicos , Doença Pulmonar Obstrutiva Crônica , Adulto , Humanos , Estudos de Coortes , Saskatchewan , Doença Pulmonar Obstrutiva Crônica/terapia , Custos de Cuidados de Saúde , Aceitação pelo Paciente de Cuidados de Saúde , Estudos Retrospectivos
8.
Dermatol Surg ; 49(6): 598-602, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37027247

RESUMO

BACKGROUND: The prevalence of work-related musculoskeletal disorders (WRMD) is increasing among all surgical specialties. OBJECTIVE: Results of a cross-sectional survey of hair transplant surgeons were analyzed, with the aims to (1) determine the prevalence of WRMD, (2) assess risk factors associated with musculoskeletal (MSK) symptoms, and (3) identify mitigation measures. MATERIALS AND METHODS: A survey pertaining to demographics, MSK-related symptoms and its impacts, and pain mitigation measures taken, if any, were distributed to 834 hair transplant surgeons. Risk factors associated with pain severity were assessed using linear regression. RESULTS: Overall, 78.5% (73 of 93) respondents had experienced pain when performing surgery. Musculoskeletal symptoms were most severe in the neck, followed by upper/lower back, and extremities. Number of grafts performed per session of follicular unit extraction positively correlated with pain severity; female surgeons and surgeons aged >71 years were at higher risk. A majority expressed concern that WRMD may limit their career and agreed to a need for improved workplace education. Strength training and ergonomic improvements of surgical procedure were not commonly adopted. CONCLUSION: In sum, WRMD can be debilitating in health care professionals. Workplace ergonomic adjustments and physical exercise programs may be warranted to better mitigate MSK symptoms.


Assuntos
Dor Musculoesquelética , Doenças Profissionais , Cirurgiões , Humanos , Feminino , Estudos Transversais , Doenças Profissionais/epidemiologia , Doenças Profissionais/etiologia , Inquéritos e Questionários , Prevalência , Cabelo
9.
J Eur Acad Dermatol Venereol ; 37(9): 1706-1717, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37210652

RESUMO

Antifungal resistance has become prevalent worldwide. Understanding the factors involved in spread of resistance allows the formulation of strategies to slow resistance development and likewise identify solutions for the treatment of highly recalcitrant fungal infections. To investigate the recent explosion of resistant strains, a literature review was performed focusing on four main areas: mechanisms of resistance to antifungal agents, diagnosis of superficial fungal infections, management, and stewardship. The use of traditional diagnostic tools such as culture, KOH analysis and minimum inhibitory concentration values on treatment were investigated and compared to the newer techniques such as molecular methods including whole genome sequencing, and polymerase chain reaction. The management of terbinafine-resistant strains is discussed. We have emphasized the need for antifungal stewardship including increasing surveillance for resistant infection.


Assuntos
Dermatomicoses , Onicomicose , Humanos , Antifúngicos/uso terapêutico , Antifúngicos/farmacologia , Onicomicose/diagnóstico , Onicomicose/tratamento farmacológico , Onicomicose/microbiologia , Terbinafina/uso terapêutico , Dermatomicoses/tratamento farmacológico , Farmacorresistência Fúngica
10.
J Eur Acad Dermatol Venereol ; 37(2): 243-255, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36196052

RESUMO

Onychomycosis is caused by dermatophytes, non-dermatophytes and yeasts. It has a global prevalence of 5.5%, requires long treatment periods, and has high relapse rates following therapy. Oral antifungals are generally the most common treatment. While effective, they have limitations such as drug-drug interactions, hepatotoxicity and adverse side effects; thus, they cannot be used in several populations. Topical antifungals do not have the safety limitations but are typically not as effective. The primary challenge of topical treatment is the permeation of drug molecules across the nail plate barrier, which is a highly cross-linked keratin network. The use of drugs and formulations with favourable characteristics such as small size, absence of lipophilicity, hydrophilic nature, hydrating properties and appropriate pH can greatly improve permeation. Here, we review physical, nanoparticle-based, formulation-based, mechanical and chemical drug delivery strategies to improve the permeation of drugs across the nail plate.


Assuntos
Onicomicose , Humanos , Onicomicose/tratamento farmacológico , Antifúngicos , Preparações Farmacêuticas , Unhas , Sistemas de Liberação de Medicamentos , Administração Tópica
11.
Pediatr Dermatol ; 39(2): 173-181, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35060179

RESUMO

BehÒ«et disease is a multisystem inflammatory disease and variable vessel vasculitis involving primarily the oral and genital mucosa, skin, and eyes. Diagnosis is challenging due to the lack of a specific diagnostic test and overlap with other autoinflammatory diseases. Treatment of pediatric BehÒ«et disease aims to reduce inflammation and prevent future flares. The goal of this review is to provide guidance on the diagnostic workup and multidisciplinary approach of pediatric BehÒ«et disease and review evidence-based treatment strategies for patients with refractory mucocutaneous manifestations.


Assuntos
Síndrome de Behçet , Vasculite , Síndrome de Behçet/diagnóstico , Criança , Humanos , Inflamação , Pele
12.
Molecules ; 27(3)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35164144

RESUMO

The CDK4/6 inhibitor palbociclib, combined with endocrine therapy, has been shown to be effective in postmenopausal women with estrogen receptor-positive, HER2-negative advanced or metastatic breast cancer. However, palbociclib is not as effective in the highly aggressive, triple-negative breast cancer that lacks sensitivity to chemotherapy or endocrine therapy. We hypothesized that conjugation of the near-infrared dye MHI-148 with palbociclib can produce a potential theranostic in triple-negative, as well as estrogen receptor-positive, breast cancer cells. In our study, the conjugate was found to have enhanced activity in all mammalian cell lines tested in vitro. However, the conjugate was cytotoxic and did not induce G1 cell cycle arrest in breast cancer cells, suggesting its mechanism of action differs from the parent compound palbociclib. The study highlights the importance of investigating the mechanism of conjugates of near-infrared dyes to therapeutic compounds, as conjugation can potentially result in a change of mechanism or target, with an enhanced cytotoxic effect in this case.


Assuntos
Antineoplásicos , Neoplasias da Mama/tratamento farmacológico , Carbocianinas , Citotoxinas , Indóis , Piperazinas , Piridinas , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Neoplasias da Mama/metabolismo , Células CHO , Carbocianinas/química , Carbocianinas/farmacologia , Cricetulus , Citotoxinas/química , Citotoxinas/farmacologia , Feminino , Células HEK293 , Humanos , Indóis/química , Indóis/farmacologia , Piperazinas/química , Piperazinas/farmacologia , Piridinas/química , Piridinas/farmacologia
13.
Bioorg Med Chem Lett ; 50: 128336, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34438012

RESUMO

Cytoprotective agents are mainly used to protect the gastrointestinal tract linings and in the treatment of gastric ulcers. These agents are devoid of appreciable cytotoxic or cytostatic effects, and medicinal chemistry efforts to modify them into anticancer agents are rare. A drug repurposing campaign initiated in our laboratory with the primary focus of discovering brain cancer drugs resulted in drug-dye conjugate 1, a combination of the cytoprotective agent troxipide and heptamethine cyanine dye MHI 148. The drug-dye conjugate 1 was evaluated in three different patient-derived adult glioblastoma cell lines, commercially available U87 glioblastoma, and one paediatric glioblastoma cell line. In all cases, the conjugate 1 showed potent cytotoxic activity with nanomolar potency (EC50: 267 nM). Interestingly, troxipide alone does not show any cytotoxic and cytostatic activity in the above cell lines. We also observe a synergistic effect of 1 with temozolomide (TMZ), the standard drug used for glioblastoma treatment, even though the cell lines we used in this study were resistant to TMZ treatment. Herein we disclose the synthesis and in vitro activity of drug-dye conjugate 1 for treatment of difficult-to-treat brain cancers such as glioblastoma.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Carbocianinas/química , Glioblastoma/tratamento farmacológico , Indóis/química , Piperidinas/química , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular , Desenho de Fármacos , Reposicionamento de Medicamentos , Quimioterapia Combinada , Humanos , Estrutura Molecular , Temozolomida/administração & dosagem , Temozolomida/uso terapêutico
14.
Skin Therapy Lett ; 26(1): 5-10, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33539062

RESUMO

Onychomycosis, a difficult-to-treat fungal nail infection, is more prevalent in the elderly. Efinaconazole 10% topical solution is a firstline therapy for onychomycosis, based on phase III trials of 12-month treatment; the slow growth of onychomycotic nails suggests a longer treatment period may increase efficacy. This is the first efficacy and safety data for a 24-month duration of efinaconazole 10% topical solution treatment for onychomycosis. Enrolled patients (N = 101) with mild to moderate distal lateral subungual onychomycosis applied efinaconazole to all affected toenails once daily for 18-24 months. Efficacy and safety were evaluated at months 6, 12, 18, and 24 (M6, M12, M18, and M24). The study is ongoing; to date, 47 patients have completed to M24. Mycological cure (MC) was 60.0% at M12, increasing to 74.2% at M24; effective cure (MC and ≤10% clinical involvement of the target toenail) was 17.8% at M12, rising to 19.4% at M24. Mild to moderate application site reactions were the only efinaconazole-related adverse events in 8 patients (7.9%). Increased age, increased severity of onychomycosis, and the presence of mixed infections (dermatophyte plus non-dermatophyte moulds) may drive a need for longer treatment durations. Although the data are interim, there is a trend of increasing efficacy beyond M12 use, without increased safety risk, even in patients >70 years of age.


Assuntos
Antifúngicos/uso terapêutico , Dermatoses do Pé/tratamento farmacológico , Onicomicose/tratamento farmacológico , Triazóis/uso terapêutico , Administração Cutânea , Idoso , Antifúngicos/administração & dosagem , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Triazóis/administração & dosagem
15.
Bioconjug Chem ; 31(7): 1724-1739, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32530288

RESUMO

This review covers the application of heptamethine cyanine dye (HMCD) mediated drug delivery. A relatively small number of HMCDs possess tumor targeting abilities, and this has spurred interest from research groups to explore them as drug delivery systems. Their tumor selectivity is primarily attributed to their uptake by certain isoforms of organic anion transporting polypeptides (OATPs) which are overexpressed in cancer tissues, although there are other possible mechanisms for the observed selectivity still under investigation. This specificity is confirmed using various cancer cell lines and is accompanied by moderate cytotoxicity. Their retention in tumor tissue is facilitated by the formation of albumin adducts as revealed by published mechanistic studies. HMCDs are also organelle selective dyes with specificity toward mitochondria and lysosomes, and with absorption and emission in the near-infrared region. This makes them valuable tools for biomedical imaging, especially in the field of fluorescence-guided tumor surgery. Furthermore, conjugating antitumor agents to HMCDs is providing novel drugs that await clinical testing. HMCD development as theranostic agents with dual tumor targeting and treatment capability signals a new approach to overcome drug resistance (mediated through evasion of efflux pumps) and systemic toxicity, the two parameters which have long plagued drug discovery.


Assuntos
Antineoplásicos/administração & dosagem , Carbocianinas/administração & dosagem , Corantes/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Linfoma de Burkitt/tratamento farmacológico , Carbocianinas/farmacologia , Carbocianinas/uso terapêutico , Descoberta de Drogas , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Humanos , Neoplasias Renais/tratamento farmacológico , Masculino , Medicina de Precisão , Neoplasias da Próstata/tratamento farmacológico
16.
Bioorg Med Chem Lett ; 30(14): 127252, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32527552

RESUMO

We describe the synthesis and in vitro activity of drug-dye conjugate 1, which is a combination of the PARP inhibitor rucaparib and heptamethine cyanine dye IR-786. The drug-dye conjugate 1 was evaluated in three different patient-derived glioblastoma cell lines and showed strong cytotoxic activity with nanomolar potency (EC50: 128 nM), which was a 780 fold improvement over rucaparib itself. We also observe a synergistic effect of 1 with temozolomide (TMZ), the standard drug for treatment for glioblastoma even though these cell lines were resistant to TMZ treatment. We envisage such conjugates to be worth exploring for their utility in the treatment of various brain cancers.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Carbocianinas/farmacologia , Glioblastoma/tratamento farmacológico , Indóis/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Poli(ADP-Ribose) Polimerases/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Carbocianinas/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Indóis/química , Estrutura Molecular , Inibidores de Poli(ADP-Ribose) Polimerases/síntese química , Inibidores de Poli(ADP-Ribose) Polimerases/química , Relação Estrutura-Atividade
17.
BMC Genomics ; 20(1): 420, 2019 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-31133004

RESUMO

BACKGROUND: The process of crop domestication often consists of two stages: initial domestication, where the wild species is first cultivated by humans, followed by diversification, when the domesticated species are subsequently adapted to more environments and specialized uses. Selective pressure to increase sugar accumulation in certain varieties of the cereal crop Sorghum bicolor is an excellent example of the latter; this has resulted in pronounced phenotypic divergence between sweet and grain-type sorghums, but the genetic mechanisms underlying these differences remain poorly understood. RESULTS: Here we present a new reference genome based on an archetypal sweet sorghum line and compare it to the current grain sorghum reference, revealing a high rate of nonsynonymous and potential loss of function mutations, but few changes in gene content or overall genome structure. We also use comparative transcriptomics to highlight changes in gene expression correlated with high stalk sugar content and show that changes in the activity and possibly localization of transporters, along with the timing of sugar metabolism play a critical role in the sweet phenotype. CONCLUSIONS: The high level of genomic similarity between sweet and grain sorghum reflects their historical relatedness, rather than their current phenotypic differences, but we find key changes in signaling molecules and transcriptional regulators that represent new candidates for understanding and improving sugar metabolism in this important crop.


Assuntos
Genoma de Planta , Sorghum/genética , Açúcares/metabolismo , DNA de Plantas/química , Perfilação da Expressão Gênica , Genômica/normas , Genótipo , Padrões de Referência , Homologia de Sequência do Ácido Nucleico , Sorghum/metabolismo
18.
Bioorg Med Chem Lett ; 29(18): 2617-2621, 2019 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-31378572

RESUMO

We describe the synthesis of drug-dye conjugate 1 between anaplastic lymphoma kinase inhibitor Crizotinib and heptamethine cyanine dye IR-786. The drug-dye conjugate 1 was evaluated in three different patient-derived glioblastoma cell lines and showed potent cytotoxic activity with nanomolar potency (EC50: 50.9 nM). We also demonstrate evidence for antiproliferative activity of 1 with single digit nanomolar potency (IC50: 4.7 nM). Furthermore, the cytotoxic effects conveyed a dramatic, 110-fold improvement over Crizotinib. This improvement was even more pronounced (492-fold) when 1 was combined with Temozolomide, the standard drug for treatment for glioblastoma. This work lays the foundation for future exploration of similar tyrosine kinase inhibitor drug-dye conjugates for the treatment of glioblastoma.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Carbocianinas/farmacologia , Crizotinibe/farmacologia , Citostáticos/farmacologia , Corantes Fluorescentes/farmacologia , Glioblastoma/tratamento farmacológico , Antineoplásicos/síntese química , Antineoplásicos/química , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/metabolismo , Carbocianinas/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Crizotinibe/química , Citostáticos/síntese química , Citostáticos/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Glioblastoma/diagnóstico por imagem , Glioblastoma/metabolismo , Humanos , Estrutura Molecular , Imagem Óptica , Relação Estrutura-Atividade
19.
Cult Med Psychiatry ; 43(1): 134-159, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30121724

RESUMO

It is important to recognize that experiences of racial and gendered violence are a sad legacy of colonialism. The experiences of historical trauma are on-going. These affect the mental and physical wellbeing of individuals, families and communities. Addressing historical trauma through community-informed practices is central to creating space for meaningful change. This paper outlines results from a seven-week activity-based research workshop conducted on three separate occasions with urban-based First Nations and Metis women and girls (aged 8-12). Using a decolonizing theoretical framework, this paper examines data collected within three specific arts-based activities: empowerment bracelets, "I'm proud of you" charm bracelets and "Who I am" pictures. Women were hesitant to discuss future plans, as many were not confident that their daughters would be in contact with their maternal families when they become teenagers. Girls observed and mimicked the thoughts and actions of their mothers, step-mothers, aunts, older sisters and grandmothers. They demonstrated the role they already play within the discourse of what it means to be female living within their communities. This paper concludes with the implicit harm reduction approach women and girls used when exploring the impacts of trauma while envisioning a healthier future.


Assuntos
Colonialismo , Redução do Dano , Indígenas Norte-Americanos/psicologia , Relação entre Gerações , Comportamento Autodestrutivo/prevenção & controle , Adolescente , Adulto , Arteterapia/métodos , Criança , Família , Feminino , Humanos , Saúde Mental , Comportamento Autodestrutivo/etnologia
20.
Health Promot Pract ; 20(5): 648-651, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31253061

RESUMO

The authors met during a career development experience where they discussed the commonalities of their successes and challenges conducting creative strengths-based health promotion research with underserved communities during their graduate and postgraduate training. They identified changes to health promotion pedagogy that they would like to see in the future. These include understanding both the strengths and the challenges of creative strengths-based health promotion research conducted with underserved communities, ensuring that reflexivity and flexibility is a component of the process, developing support networks for trainees, understanding personal limitations to effect change, and supporting self-care. They hope that trainees and health education programs will learn from their experiences.


Assuntos
Educação de Pós-Graduação/organização & administração , Promoção da Saúde/organização & administração , Área Carente de Assistência Médica , Apoio ao Desenvolvimento de Recursos Humanos/organização & administração , Canadá , Humanos
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