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1.
J Nucl Cardiol ; : 101864, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38663459

RESUMO

Different types of vasculitis can be distinguished according to the blood vessel's size that is preferentially affected: large-vessel, medium-vessel, and small-vessel vasculitides. Giant cell arteritis (GCA) and Takayasu's arteritis (TAK) are the main forms of large-vessel vasculitis, and may lead to lumen narrowing. Clinical manifestations of arterial narrowing on the short- and long term include vision loss, stroke, limb ischemia, and heart failure. Imaging tools are well established diagnostic tests for large-vessel vasculitis and may aid therapy monitoring in selected cases while providing important information regarding the occurrence of vascular damage, tissue and organ complications. This review aims to provide the current status of multimodality imaging for the diagnosis and identification of vascular complications in the field of large vessel vasculitis.

2.
Macromol Rapid Commun ; : e2400129, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38778746

RESUMO

Biopolymeric implantable patches are popular scaffolds for myocardial regeneration applications. Besides being biocompatible, they can be tailored to have required properties and functionalities for this application. Recently, fibrillar biobased nanostructures prove to be valuable in the development of functional biomaterials for tissue regeneration applications. Here, periodate-oxidized nanofibrillated cellulose (OxNFC) is blended with lysozyme amyloid nanofibrils (LNFs) to prepare a self-crosslinkable patch for myocardial implantation. The OxNFC:LNFs patch shows superior wet mechanical properties (60 MPa for Young's modulus and 1.5 MPa for tensile stress at tensile strength), antioxidant activity (70% scavenging activity under 24 h), and bioresorbability ratio (80% under 91 days), when compared to the patches composed solely of NFC or OxNFC. These improvements are achieved while preserving the morphology, required thermal stability for sterilization, and biocompatibility toward rat cardiomyoblast cells. Additionally, both OxNFC and OxNFC:LNFs patches reveal the ability to act as efficient vehicles to deliver spermine modified acetalated dextran nanoparticles, loaded with small interfering RNA, with 80% of delivery after 5 days. This study highlights the value of simply blending OxNFC and LNFs, synergistically combining their key properties and functionalities, resulting in a biopolymeric patch that comprises valuable characteristics for myocardial regeneration applications.

3.
J Fish Biol ; 104(6): 1947-1959, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38553979

RESUMO

A new species of characid with remarkable sexual characteristics is described from the upper Guayabero River drainage from the Orinoco basin in Colombia. The new species is included in the genus Monotocheirodon by sharing most of the previously proposed diagnostic features of this genus. It differs from all Stevardiinae by the combination, in adult males, of an enlarged urogenital papilla in contact with the first anal-fin unbranched ray and a highly modified anal fin with enlarged and distally elongated first and second branched anal-fin rays, forming a gonopodium-like structure. In addition, it differs from congeners by the presence of an adipose fin, an incomplete lateral line, an ascending process of the premaxilla dorsally oriented, and a long snout. The new species was discovered from a poorly sampled region in Colombia and is an unexpected new record given its disjunct geographic distribution from other species of the genus. Monotocheirodon species were previously known from piedmont drainages in Bolivia and Peru. The conservation status of the new species is herein categorized following IUCN criteria.


Assuntos
Characidae , Rios , Caracteres Sexuais , Animais , Colômbia , Masculino , Feminino , Characidae/anatomia & histologia , Characidae/classificação
4.
J Magn Reson Imaging ; 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38053468

RESUMO

BACKGROUND: Pancreatic cystic lesions (PCLs) are frequent on MRI and are thought to be associated with pancreatic adenocarcinoma (PDAC) necessitating long-term surveillance based on older studies suffering from selection bias. PURPOSE: To establish the percentage of patients with PCLs on MRI with a present or future PDAC. STUDY TYPE: Systematic review, meta-analysis. POPULATION: Adults with PCLs on MRI and a present or future diagnosis of PDAC were eligible. MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Scopus were searched to April 2022 (PROSPERO:CRD42022320502). Studies limited to PCLs not requiring surveillance, <100 patients, or those with a history/genetic risk of PDAC were excluded. FIELD STRENGTH/SEQUENCE: ≥1.5 T with ≥1 T2-weighted sequence. ASSESSMENT: Two investigators extracted data, with discrepancies resolved by a third. QUADAS-2 assessed bias. PDAC was diagnosed using a composite reference standard. STATISTICAL TESTS: A meta-analysis of proportions was performed at the patient-level with 95% confidence intervals (95% CI). RESULTS: Eight studies with 1289 patients contributed to the percentage of patients with a present diagnosis of PDAC, and 10 studies with 3422 patients to the percentage with a future diagnosis. Of patients with PCLs on MRI, 14.8% (95% CI 2.4-34.9) had a PDAC at initial MRI, which decreased to 6.0% (2.2-11.3) for studies at low risk of bias. For patients without PDAC on initial MRI, 2.0% (1.1-3.2) developed PDAC during surveillance, similar for low risk of bias studies at 1.9% (0.7-3.6), with no clear trend of increased PDAC for longer surveillance durations. For patients without worrisome features or high-risk stigmata, 0.9% (0.1-2.2) developed PDAC during surveillance. Of 10, eight studies had a median surveillance ≥3 years (range 3-157 months). Sources of bias included retrospectively limiting PCLs to those with histopathology and inconsistent surveillance protocols. DATA CONCLUSION: A low percentage of patients with PCLs on MRI develop PDAC while on surveillance. The first MRI revealing a PCL should be scrutinized for PDAC. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

5.
J Fish Biol ; 103(5): 1073-1084, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37427785

RESUMO

A new rheophilic species of the genus Rineloricaria is described for the Amazon basin in Colombia. Rineloricaria cachivera n. sp. differs from its congeners by having anterior to the first predorsal plate, an inconspicuous saddle-like mark; the presence of dark, diffuse blotches, present as unified dark colouration along most of the dorsal portion of the head, without bands or spots on the head; a long snout that occupies more than half the head length (HL), between 58.0% and 66.3% HL; a naked portion on the cleithral area from the border of lower lip reaching the origin of pectoral fin; and by having five series of lateral plates in longitudinal rows below the dorsal fin. The new species is morphologically similar to Rineloricaria daraha; however, it can be distinguished by the presence of six branched pectoral fin rays (vs. seven) and the lower lip surface with short thick papillae (vs. long finger papillae). An identification key to the Rineloricaria species of the Amazon River basin in Colombia is provided. The new species is herein categorized as Least Concern, following the IUCN criteria.


Assuntos
Peixes-Gato , Papilas Gustativas , Animais , Rios , Colômbia , Brasil
6.
Int J Mol Sci ; 24(13)2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-37445810

RESUMO

Intracellular pH (pHi) regulation is a challenge for the exocrine pancreas, where the luminal secretion of bicarbonate-rich fluid is accompanied by interstitial flows of acid. This acid-base transport requires a plethora of ion transporters, including bicarbonate transporters and the Na+/H+ exchanger isoform 1 (NHE1), which are dysregulated in Pancreatic Ductal Adenocarcinoma (PDAC). PDAC progression is favored by a Collagen-I rich extracellular matrix (ECM) which exacerbates the physiological interstitial acidosis. In organotypic cultures of normal human pancreatic cells (HPDE), parenchymal cancer cells (CPCs) and cancer stem cells (CSCs) growing on matrices reproducing ECM changes during progression, we studied resting pHi, the pHi response to fluxes of NaHCO3 and acidosis and the role of NHE1 in pHi regulation. Our findings show that: (i) on the physiological ECM, HPDE cells have the most alkaline pHi, followed by CSCs and CPCs, while a Collagen I-rich ECM reverses the acid-base balance in cancer cells compared to normal cells; (ii) both resting pHi and pHi recovery from an acid load are reduced by extracellular NaHCO3, especially in HPDE cells on a normal ECM; (iii) cancer cell NHE1 activity is less affected by NaHCO3. We conclude that ECM composition and the fluctuations of pHe cooperate to predispose pHi homeostasis towards the presence of NaHCO3 gradients similar to that expected in the tumor.


Assuntos
Acidose , Neoplasias , Humanos , Concentração de Íons de Hidrogênio , Bicarbonatos/metabolismo , Matriz Extracelular/metabolismo , Colágeno Tipo I , Ductos Pancreáticos/metabolismo , Células Epiteliais/metabolismo , Trocadores de Sódio-Hidrogênio
7.
Lancet Oncol ; 23(11): 1419-1429, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36174583

RESUMO

BACKGROUND: Despite the high burden of cervical cancer, access to preventive measures remains low in India. A single-dose immunisation schedule could facilitate the scale-up of human papillomavirus (HPV) vaccination, contributing to global elimination of cervical cancer. We projected the effect of single-dose quadrivalent HPV vaccination in India in comparison with no vaccination or to a two-dose schedule. METHODS: In this modelling study, we adapted an HPV transmission model (EpiMetHeos) to Indian data on sexual behaviour (from the Demographic and Health Survey and the Indian National AIDS Control Organisation), HPV prevalence data (from two local surveys, from the states of Tamil Nadu and West Bengal), and cervical cancer incidence data (from Cancer Incidence in Five Continents for the period 2008-12 [volume XI], and the Indian National Centre for Disease Informatics and Research for the period 2012-16). Using the model, we projected the nationwide and state-specific effect of HPV vaccination on HPV prevalence and cervical cancer incidence, and lifetime risk of cervical cancer, for 100 years after the introduction of vaccination or in the first 50 vaccinated birth cohorts. Projections were derived under a two-dose vaccination scenario assuming life-long protection and under a single-dose vaccination scenario with protection duration assumptions derived from International Agency for Research on Cancer (IARC) India vaccine trial data, in combination with different vaccination coverages and catch-up vaccination age ranges. We used two thresholds to define cervical cancer elimination: an age-standardised incidence rate of less than 4 cases per 100 000 woman-years, and standardised lifetime risk of less than 250 cases per 100 000 women born. FINDINGS: Assuming vaccination in girls aged 10 years, with 90% coverage, and life-long protection by two-dose or single-dose schedule, HPV vaccination could reduce the prevalence of HPV16 and HPV18 infection by 97% (80% UI 96-99) in 50 years, and the lifetime risk of cervical cancer by 71-78% from 1067 cases per 100 000 women born under a no vaccination scenario to 311 (80% UI 284-339) cases per 100 000 women born in the short term and 233 (219-252) cases per 100 000 women born in the long term in vaccinated cohorts. Under this scenario, we projected that the age-standardised incidence rate threshold for elimination could be met across India (range across Indian states: 1·6 cases [80% UI 1·5-1·7] to 4·0 cases [3·8-4·4] per 100 000 woman-years), while the complementary threshold based on standardised lifetime risk was attainable in 17 (68%) of 25 states, but not nationwide (range across Indian states: 207 cases [80% UI 194-223] to 477 cases [447-514] per 100 000 women born). Under the considered assumptions of waning vaccine protection, single-dose vaccination was projected to have a 21-100% higher per-dose efficiency than two-dose vaccination. Single-dose vaccination with catch-up for girls and women aged 11-20 years was more impactful than two-dose vaccination without catch-up, with reduction of 39-65% versus 38% in lifetime risk of cervical cancer across the ten catch-up birth cohorts and the first ten routine vaccination birth cohorts. INTERPRETATION: Our evidence-based projections suggest that scaling up cervical cancer prevention through single-dose HPV vaccination could substantially reduce cervical cancer burden in India. FUNDING: The Bill & Melinda Gates Foundation.


Assuntos
Infecções por Papillomavirus , Vacinas contra Papillomavirus , Neoplasias do Colo do Útero , Feminino , Humanos , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/prevenção & controle , Infecções por Papillomavirus/tratamento farmacológico , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/prevenção & controle , Índia/epidemiologia , Papillomavirus Humano 16
8.
Theor Appl Genet ; 135(2): 405-419, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34807267

RESUMO

KEY MESSAGE: New forms of the coefficient of determination can help to forecast the accuracy of genomic prediction and optimize experimental designs in multi-environment trials with genotype-by-environment interactions. In multi-environment trials, the relative performance of genotypes may vary depending on the environmental conditions, and this phenomenon is commonly referred to as genotype-by-environment interaction (G[Formula: see text]E). With genomic prediction, G[Formula: see text]E can be accounted for by modeling the genetic covariance between trials, even when the overall experimental design is highly unbalanced between trials, thanks to the genomic relationship between genotypes. In this study, we propose new forms of the coefficient of determination (CD, i.e., the expected model-based square correlation between a genetic value and its corresponding prediction) that can be used to forecast the genomic prediction reliability of genotypes, both for their trial-specific performance and their mean performance. As the expected prediction reliability based on these new CD criteria is generally a good approximation of the observed reliability, we demonstrate that they can be used to optimize multi-environment trials in the presence of G[Formula: see text]E. In addition, this reliability may be highly variable between genotypes, especially in unbalanced designs with complex pedigree relationships between genotypes. Therefore, it can be useful for breeders to assess it before selecting genotypes based on their predicted genetic values. Using a wheat population evaluated both for simulated and phenology traits, and two maize populations evaluated for grain yield, we illustrate this approach and confirm the value of our new CD criteria.


Assuntos
Melhoramento Vegetal , Projetos de Pesquisa , Genômica , Genótipo , Modelos Genéticos , Fenótipo , Reprodutibilidade dos Testes
9.
Med Res Rev ; 41(3): 1499-1538, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33274768

RESUMO

Prostate cancer (PCa), one of the most commonly diagnosed cancers worldwide, still presents important unmet clinical needs concerning treatment. In the last years, the metabolic reprogramming and the specificities of tumor cells emerged as an exciting field for cancer therapy. The unique features of PCa cells metabolism, and the activation of specific metabolic pathways, propelled the use of metabolic inhibitors for treatment. The present work revises the knowledge of PCa metabolism and the metabolic alterations that underlie the development and progression of the disease. A focus is given to the role of bioenergetic sources, namely, glucose, lipids, and glutamine sustaining PCa cell survival and growth. Moreover, it is described as the action of oncogenes/tumor suppressors and sex steroid hormones in the metabolic reprogramming of PCa. Finally, the status of PCa treatment based on the inhibition of metabolic pathways is presented. Globally, this review updates the landscape of PCa metabolism, highlighting the critical metabolic alterations that could have a clinical and therapeutic interest.


Assuntos
Neoplasias da Próstata , Humanos , Masculino , Redes e Vias Metabólicas , Oncogenes , Neoplasias da Próstata/tratamento farmacológico
10.
Int J Mol Sci ; 22(8)2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33921242

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest malignancies. Present-day treatments have not shown real improvements in reducing the high mortality rate and the short survival of the disease. The average survival is less than 5% after 5 years. New innovative treatments are necessary to curtail the situation. The very dense pancreatic cancer stroma is a barrier that impedes the access of chemotherapeutic drugs and at the same time establishes a pro-proliferative symbiosis with the tumor, thus targeting the stroma has been suggested by many authors. No ideal drug or drug combination for this targeting has been found as yet. With this goal in mind, here we have explored a different complementary treatment based on abundant previous publications on repurposed drugs. The cell surface protein CD44 is the main receptor for hyaluronan binding. Many malignant tumors show over-expression/over-activity of both. This is particularly significant in pancreatic cancer. The independent inhibition of hyaluronan-producing cells, hyaluronan synthesis, and/or CD44 expression, has been found to decrease the tumor cell's proliferation, motility, invasion, and metastatic abilities. Targeting the hyaluronan-CD44 pathway seems to have been bypassed by conventional mainstream oncological practice. There are existing drugs that decrease the activity/expression of hyaluronan and CD44: 4-methylumbelliferone and bromelain respectively. Some drugs inhibit hyaluronan-producing cells such as pirfenidone. The association of these three drugs has never been tested either in the laboratory or in the clinical setting. We present a hypothesis, sustained by hard experimental evidence, suggesting that the simultaneous use of these nontoxic drugs can achieve synergistic or added effects in reducing invasion and metastatic potential, in PDAC. A non-toxic, low-cost scheme for inhibiting this pathway may offer an additional weapon for treating pancreatic cancer.


Assuntos
Adenocarcinoma/tratamento farmacológico , Carcinoma Ductal Pancreático/tratamento farmacológico , Receptores de Hialuronatos/genética , Hialuronan Sintases/genética , Ácido Hialurônico/genética , Adenocarcinoma/genética , Adenocarcinoma/patologia , Bromelaínas/uso terapêutico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Receptores de Hialuronatos/antagonistas & inibidores , Hialuronan Sintases/antagonistas & inibidores , Ácido Hialurônico/antagonistas & inibidores , Himecromona/uso terapêutico , Terapia de Alvo Molecular , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Metástase Neoplásica , Piridonas/farmacologia , Piridonas/uso terapêutico , Transdução de Sinais/efeitos dos fármacos
11.
J Fish Biol ; 98(4): 1186-1191, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33244758

RESUMO

Two specimens of Micromyzon akamai, an eyeless and miniaturized species previously known only from the deep channels of the eastern Amazon basin in Brazil, are reported from the Curaray River, a tributary of the Napo River in Ecuador. The new specimens are the first records of Micromyzon in the headwaters of the Amazon River and the first records of M. akamai outside Brazil. External morphological characters and a phylogenetic analysis of cytochrome c oxidase I (coI) gene support the identification of the new specimens as M. akamai. Nevertheless, the new specimens also indicate that some features previously hypothesized to be apomorphic for M. akamai are intraspecifically variable.


Assuntos
Distribuição Animal , Peixes-Gato/fisiologia , Animais , Brasil , Peixes-Gato/anatomia & histologia , Equador , Filogenia , Rios , Especificidade da Espécie
12.
Nonlinear Dyn ; 105(4): 3763-3773, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34456509

RESUMO

Despite the huge relevance of vaccines for preventing COVID-19, physical isolation and quarantine of infected individuals are still the key strategies to fight against the COVID-19 pandemic. Based on a COVID-19 transmission epidemiological model governed by ordinary differential equations, here we propose an intermittent non-pharmacological protocol to control the fraction of infected individuals. In our approach, unlike what generically happens for numerical simulation models, we provide a global analysis of the model, giving qualitative information about every initial condition. Under some simple hypothesis and variations of parameters, we present some bifurcations and we are able to predict the minimum social distancing effort that do not collapse the health system.

13.
J Neurochem ; 153(4): 455-467, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31811731

RESUMO

Brain adenosine concentrations can reach micromolar concentrations in stressful situations such as stroke, neurodegenerative diseases or hypoxic regions of brain tumours. Adenosine can act by receptor-independent mechanism by reversing the reaction catalysed by S-adenosylhomocysteine (SAH) hydrolase, leading to SAH accumulation and inhibition of S-adenosylmethionine (SAM)-dependent methyltransferases. Astrocytes are essential in maintaining brain homeostasis but their pathological activation and uncontrolled proliferation plays a role in neurodegeneration and glioma. Adenosine can affect cell proliferation, but the effect of increased adenosine concentration on proliferation of astrocytes is not clarified and was addressed in present work. Human astrocytes (HA) were treated for 3 days with test drugs. Cell proliferation/viability was assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium assay and by cell counting. Cell death was evaluated by assessing lactate dehydrogenase release and by western blot analysis of αII-Spectrin cleavage. 30 µM-Adenosine caused a 40% ± 3% (p < .05, n = 5) reduction in cell proliferation/viability, an effect reversed by 2U/ml-adenosine deaminase, but unchanged in the presence of antagonists of any of the adenosine receptors. Adenosine alone did not induce cell death. 100 µM-Homocysteine alone caused 16% ± 3% (p < .05) decrease in HA proliferation. Combined action of adenosine and homocysteine decreased HA proliferation by 76% ± 4%, an effect higher (p < .05) than the sum of the effects of adenosine and homocysteine alone (56% ± 5%). The inhibitory effect of adenosine on HA proliferation/viability was mimicked by two adenosine kinase inhibitors and attenuated in the presence of folate (100 µM) or SAM (50-100 µM). The results suggest that adenosine reduces HA proliferation by a receptor-independent mechanism probably involving reversal of SAH hydrolase-catalysed reaction.


Assuntos
Adenosina/farmacologia , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Proliferação de Células/efeitos dos fármacos , Agonistas do Receptor Purinérgico P1/farmacologia , Receptores Purinérgicos P1/metabolismo , Proliferação de Células/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Córtex Cerebral/citologia , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Humanos
14.
J Fish Biol ; 97(6): 1748-1769, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32914431

RESUMO

Epactionotus species are known for inhabiting the rocky-bottom stretches of fast-flowing rivers in a limited geographic area along the Atlantic coast of southern Brazil. These species are endemic to single coastal river drainages (two neighbouring drainages for Epactionotus bilineatus) isolated from each other by the coastal lacustrine environments or the Atlantic Ocean. E. bilineatus is from the Maquiné and Três Forquilhas River basins, both tributaries of the Tramandaí River system, whereas E. itaimbezinho is endemic to the Mampituba River drainage and Epactionotus gracilis to the Araranguá River drainage. Recent fieldwork in the Atlantic coastal drainages of southern Brazil revealed new populations in the Urussanga, Tubarão, d'Una and Biguaçu River drainages. Iterative species delimitation using molecular data (cytochrome c oxidase subunit I) and morphology (morphometrics and meristics) was applied to evaluate species recognition of isolated populations. With regard to new data, the genus was re-diagnosed, the status of Epactionotus species/populations was re-evaluated, formerly described species were supported and population structure was recognized. As for the newly discovered populations, both morphological and molecular data strongly support the population from the Biguaçu River drainage, in Santa Catarina State, as a new species. Molecular data revealed strong per-basin population structure, which may be related to species habitat specificity and low or no dispersal among drainages.


Assuntos
Peixes-Gato/classificação , Variação Genética , Filogenia , Animais , Oceano Atlântico , Brasil , Peixes-Gato/anatomia & histologia , Peixes-Gato/genética , Deriva Genética , Rios , Especificidade da Espécie
15.
J Fish Biol ; 96(4): 886-904, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32039475

RESUMO

A new species of Trichomycterus endemic to the Ribeira de Iguape River basin, southeastern Brazil, was studied based on morphological and molecular evidence. This species had an outer layer of coloration composed of scattered, round, black or dark-brown spots smaller or equivalent in size to the circumference of the eye; eight pectoral-fin rays; 28-29 opercular odontodes; 54-56 interopercular odontodes; and supraorbital line of the laterosensory system not interrupted, with pores s2 absent. Two other species of Trichomycterus from the Ribeira de Iguape River basin are recorded, and their taxonomic status is discussed: Trichomycterus alternatus and Trichomycterus jacupiranga were not differentiated using molecular analysis but may be consistently distinguished based on morphology. The phylogenetic relationships of the co-occurring species, T. alternatus and Cambeva zonata, were inferred using mitochondrial data, reinforcing the taxonomic status of these recently revised species that have a complex taxonomy. In addition, a new combination for Trichomycterus taroba with its inclusion in the genus Cambeva is recommended.


Assuntos
Peixes-Gato/classificação , Filogenia , Animais , Brasil , Peixes-Gato/anatomia & histologia , Peixes-Gato/genética , Mitocôndrias/genética , Rios , Especificidade da Espécie
16.
Int J Mol Sci ; 22(1)2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33375106

RESUMO

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal disease. Gemcitabine (GEM) is used as the gold standard drug in PDAC treatment. However, due to its poor efficacy, it remains urgent to identify novel strategies to overcome resistance issues. In this context, an intense stroma reaction and the presence of cancer stem cells (CSCs) have been shown to influence PDAC aggressiveness, metastatic potential, and chemoresistance. METHODS: We used three-dimensional (3D) organotypic cultures grown on an extracellular matrix composed of Matrigel or collagen I to test the effect of the new potential therapeutic prodrug 4-(N)-stearoyl-GEM, called C18GEM. We analyzed C18GEM cytotoxic activity, intracellular uptake, apoptosis, necrosis, and autophagy induction in both Panc1 cell line (P) and their derived CSCs. RESULTS: PDAC CSCs show higher sensitivity to C18GEM treatment when cultured in both two-dimensional (2D) and 3D conditions, especially on collagen I, in comparison to GEM. The intracellular uptake mechanisms of C18GEM are mainly due to membrane nucleoside transporters' expression and fatty acid translocase CD36 in Panc1 P cells and to clathrin-mediated endocytosis and CD36 in Panc1 CSCs. Furthermore, C18GEM induces an increase in cell death compared to GEM in both cell lines grown on 2D and 3D cultures. Finally, C18GEM stimulated protective autophagy in Panc1 P and CSCs cultured on 3D conditions. CONCLUSION: We propose C18GEM together with autophagy inhibitors as a valid alternative therapeutic approach in PDAC treatment.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Desoxicitidina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Matriz Extracelular/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Técnicas de Cultura de Órgãos/métodos , Pró-Fármacos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Colágeno/metabolismo , Colágeno Tipo I/metabolismo , Desoxicitidina/farmacologia , Combinação de Medicamentos , Humanos , Laminina/metabolismo , Células-Tronco Neoplásicas/metabolismo , Neoplasias Pancreáticas/patologia , Proteoglicanas/metabolismo
17.
Mol Phylogenet Evol ; 140: 106604, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31470134

RESUMO

The pike-characin Oligosarcus is a group of Characidae composed of 22 species, which have mostly allopatric distributed species in southeastern South America and sympatric occurrence of few species. Oligosarcus shares a similar distribution pattern with other fish genera and therefore, can help us to understand biogeographic events that influenced freshwater fish distribution in the southeastern South America. Our paper presents the most extensive taxonomic coverage for molecular analysis of Oligosarcus and uses various methods to examine the evolutionary history of the genus. Phylogenetic relationships among species of Oligosarcus were examined using a multilocus dataset by Maximum Likelihood and Bayesian methods. A relaxed molecular clock was used to estimate lineage divergence times, which provide a framework to examine the biogeographic history of this clade across the drainage basins of southeastern South America. Oligosarcus was resolved as monophyletic with strong support, and related to lineages currently assigned to the genus Astyanax. Within Oligosarcus, two groups of approximately equal species richness were resolved as monophyletic, mainly restricted to continental and coastal drainages of southeastern South America. Oligosarcus radiation is estimated to the late Neogene, with its origin in the Pliocene and most speciation events occurring in the Pleistocene. Some apomorphic characteristics associated with piscivory (e.g. large caniniform teeth) in Oligosarcus likely have evolved once, and are convergent to similar phenotypes observed in a distantly related clade of Astyanax (formerly Bramocharax). In addition, the presence of morphological convergence within the genus Oligosarcus (e.g. trophic morphology) seems to explain the difference between the present molecular hypothesis and some previous morphological studies. Ancestral geographical range estimation using analytical methods (e.g. DIVALIKE and DEC) demonstrated the effects of different Landscape Evolution Models (LEMs) on diversification of Oligosarcus. The results suggest that the two main Oligosarcus clades evolved in allopatry in continental and coastal drainages, with subsequent range extension and vicariance events that established the modern distributions. LEM analyses indicate the importance of formation of riverine barriers across the watershed of the La Plata basin and the effects of sea-level changes during the Pleistocene for delineating lineage distributions of Oligosarcus.


Assuntos
Characidae/classificação , Filogenia , Filogeografia , Rios , Animais , Teorema de Bayes , Calibragem , Characidae/genética , Fósseis , América do Sul , Especificidade da Espécie , Fatores de Tempo
18.
Mol Phylogenet Evol ; 132: 265-274, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30528083

RESUMO

With 22 described species, Phalloceros is the most species-rich genus of Poeciliidae in South America. Phalloceros diversity is characterized by high degrees of endemism and sympatry in coastal and inland drainages in southeastern South America. The taxa are also characterized by pronounced differentiation in sexual characters (i.e., female urogenital papilla and male gonopodium), which might have contributed to their diversification. Here we estimate phylogenetic relationships based on more than 18,000 loci in 93 individuals representing 19 described species and two putative undescribed species. Morphologically defined species correspond to monophyletic species lineages, with individuals within a species clustering together in phylogenetic estimates, with the main exception being P. harpagos, supporting undiscovered diversity in this morphospecies. Shifts in the female and male sexual traits (i.e., urogenital papilla and gonopodium) occurred in concert multiple times along the phylogeny highlighting the role of sexual selection in driving divergence in this genus. Out of 22 valid species, 14 species are found in sympatry with at least one other species of this genus. However, most co-occurrences are observed among non-sister species suggesting that diversification among closely related species involved mostly allopatric speciation, with only two instances of sympatric sister-species observed. A strong mismatch in sexual traits among sympatric taxa suggests that co-existence may be linked to divergent sexual traits that maintain species genetic distinctiveness through mechanical disruptions of interbreeding.


Assuntos
Ciprinodontiformes/classificação , Animais , Biodiversidade , Ciprinodontiformes/anatomia & histologia , DNA/química , DNA/genética , DNA/metabolismo , Especiação Genética , Fenótipo , Filogenia , Filogeografia , Polimorfismo de Nucleotídeo Único , América do Sul
19.
Nature ; 499(7459): 471-5, 2013 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-23823723

RESUMO

Most great ape genetic variation remains uncharacterized; however, its study is critical for understanding population history, recombination, selection and susceptibility to disease. Here we sequence to high coverage a total of 79 wild- and captive-born individuals representing all six great ape species and seven subspecies and report 88.8 million single nucleotide polymorphisms. Our analysis provides support for genetically distinct populations within each species, signals of gene flow, and the split of common chimpanzees into two distinct groups: Nigeria-Cameroon/western and central/eastern populations. We find extensive inbreeding in almost all wild populations, with eastern gorillas being the most extreme. Inferred effective population sizes have varied radically over time in different lineages and this appears to have a profound effect on the genetic diversity at, or close to, genes in almost all species. We discover and assign 1,982 loss-of-function variants throughout the human and great ape lineages, determining that the rate of gene loss has not been different in the human branch compared to other internal branches in the great ape phylogeny. This comprehensive catalogue of great ape genome diversity provides a framework for understanding evolution and a resource for more effective management of wild and captive great ape populations.


Assuntos
Variação Genética , Hominidae/genética , África , Animais , Animais Selvagens/genética , Animais de Zoológico/genética , Sudeste Asiático , Evolução Molecular , Fluxo Gênico/genética , Genética Populacional , Genoma/genética , Gorilla gorilla/classificação , Gorilla gorilla/genética , Hominidae/classificação , Humanos , Endogamia , Pan paniscus/classificação , Pan paniscus/genética , Pan troglodytes/classificação , Pan troglodytes/genética , Filogenia , Polimorfismo de Nucleotídeo Único/genética , Densidade Demográfica
20.
An Acad Bras Cienc ; 91(suppl 1): e20180149, 2019 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-30785469

RESUMO

Fake news has been certainly the expression of the moment: from political round table discussions to newspapers to social and mainstream media. It is everywhere. With such an intense discussion and yet few effective ways to combat it, what can be done? Providing methods to fight back even the least harming hoax is a social responsibility. To look for authenticity in a wide sea of fake news, every detail is a lead. Image appearance and semantic content of text and images are some of the main properties, which can be analyzed to reveal even the slightest lie. In this vein, this work overviews some recent methods applicable to the verification of dubious content in text and images, and discusses how we can put them together as an option to curb away the proliferation of unverified and phony "facts". We briefly present the main idea behind each method, highlighting real situations where they can be applied and discussing expected results. Ultimately, we show how new research areas are working to seamlessly stitch together all these methods so as to provide a unified analysis and to establish the synchronization in space and time - the X-Coherence of heterogeneous sources of information documenting real-world events.

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