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1.
Cell ; 187(18): 4819-4823, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39121858

RESUMO

More globally diverse perspectives are needed in genomic studies and precision medicine practices on non-Europeans. Here, we illustrate this by discussing the distribution of clinically actionable genetic variants involved in drug response in Andean highlanders and Amazonians, considering their environment, history, genetic structure, and historical biases in the perception of biological diversity of Native Americans.


Assuntos
Genômica , Humanos , Variação Genética , Indígenas Sul-Americanos/genética , Genoma Humano , América do Sul , Medicina de Precisão
2.
Cell ; 185(17): 3153-3168.e18, 2022 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-35926507

RESUMO

The centromere represents a single region in most eukaryotic chromosomes. However, several plant and animal lineages assemble holocentromeres along the entire chromosome length. Here, we compare genome organization and evolution as a function of centromere type by assembling chromosome-scale holocentric genomes with repeat-based holocentromeres from three beak-sedge (Rhynchospora pubera, R. breviuscula, and R. tenuis) and their closest monocentric relative, Juncus effusus. We demonstrate that transition to holocentricity affected 3D genome architecture by redefining genomic compartments, while distributing centromere function to thousands of repeat-based centromere units genome-wide. We uncover a complex genome organization in R. pubera that hides its unexpected octoploidy and describe a marked reduction in chromosome number for R. tenuis, which has only two chromosomes. We show that chromosome fusions, facilitated by repeat-based holocentromeres, promoted karyotype evolution and diploidization. Our study thus sheds light on several important aspects of genome architecture and evolution influenced by centromere organization.


Assuntos
Centrômero , Cyperaceae , Animais , Centrômero/genética , Cyperaceae/genética , Evolução Molecular , Cariótipo , Plantas/genética
3.
Plant J ; 118(6): 1832-1847, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38461471

RESUMO

Juncus is the largest genus of Juncaceae and was considered holocentric for a long time. Recent findings, however, indicated that 11 species from different clades of the genus have monocentric chromosomes. Thus, the Juncus centromere organization and evolution need to be reassessed. We aimed to investigate the major repetitive DNA sequences of two accessions of Juncus effusus and its centromeric structure by employing whole-genome analyses, fluorescent in situ hybridization, CENH3 immunodetection, and chromatin immunoprecipitation sequencing. We showed that the repetitive fraction of the small J. effusus genome (~270 Mbp/1C) is mainly composed of Class I and Class II transposable elements (TEs) and satellite DNAs. Three identified satellite DNA families were mainly (peri)centromeric, with two being associated with the centromeric protein CENH3, but not strictly centromeric. Two types of centromere organization were discerned in J. effusus: type 1 was characterized by a single CENH3 domain enriched with JefSAT1-155 or JefSAT2-180, whereas type 2 showed multiple CENH3 domains interrupted by other satellites, TEs or genes. Furthermore, while type 1 centromeres showed a higher degree of satellite identity along the array, type 2 centromeres had less homogenized arrays along the multiple CENH3 domains per chromosome. Although the analyses confirmed the monocentric organization of J. effusus chromosomes, our data indicate a more dynamic arrangement of J. effusus centromeres than observed for other plant species, suggesting it may constitute a transient state between mono- and holocentricity.


Assuntos
Centrômero , Cromossomos de Plantas , DNA Satélite , Hibridização in Situ Fluorescente , Centrômero/genética , Cromossomos de Plantas/genética , DNA Satélite/genética , Genoma de Planta/genética , Elementos de DNA Transponíveis/genética , DNA de Plantas/genética , Sequências Repetitivas de Ácido Nucleico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
4.
J Comput Chem ; 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39212073

RESUMO

Intramolecular charge transfer (ICT) effects of para-nitroaniline (pNA) in eight solvents (cyclohexane, toluene, acetic acid, dichloroethane, acetone, acetonitrile, dimethylsulfoxide, and water) are investigated extensively. The second-order algebraic diagrammatic construction, ADC(2), ab initio wave function is employed with the COSMO implicit and discrete multiscale solvation methods. We found a decreasing amine group torsion angle with increased solvent polarity and a linear correlation between the polarity and ADC(2) transition energies. The first absorption band involves π → π* transitions with ICT from the amine and the benzene ring to the nitro group, increased by 4%-11% for different solvation models of water compared to the vacuum. A second band of pNA is characterized for the first time. This band is primarily a local excitation on the nitro group, including some ICT from the amine group to the benzene ring that decreases with the solvent polarity. For cyclohexane, the COSMO implicit solvent model shows the best agreement with the experiment, while the explicit model has the best agreement for water.

5.
Mol Ecol ; : e17510, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39248108

RESUMO

Fluctuations in genomic repetitive fractions (repeatome) are known to impact several facets of evolution, such as ecological adaptation and speciation processes. Therefore, investigating the divergence of repetitive elements can provide insights into an important evolutionary force. However, it is not clear how the different repetitive element clades are impacted by the different factors such as ecological changes and/or phylogeny. To discuss this, we used the Neotropical legume genus Erythrostemon (Caesalpinioideae) as a model, given its ancient origin (~33 Mya), lineage-specific niche conservatism, macroecological heterogeneity, and disjunct distribution in Meso- and South American (MA and SA respectively) lineages. We performed a comparative repeatomic analysis of 18 Erythrostemon species to test the impact of environmental variables over repeats diversification. Overall, repeatome composition was diverse, with high abundances of satDNAs and Ty3/gypsy-Tekay transposable elements, predominantly in the MA and SA lineages respectively. However, unexpected repeatome profiles unrelated to the phylogeny/biogeography were found in a few MA (E. coccineus, E. pannosus and E. placidus) and SA (E. calycinus) species, related to reticulate evolution and incongruence between nuclear and plastid topology, suggesting ancient hybridizations. The plesiomorphic Tekay and satDNA pattern was altered in the MA-sensu stricto subclade with a striking genomic differentiation (expansion of satDNA and retraction of Tekay) associated with the colonization of a new environment in Central America around 20 Mya. Our data reveal that the current species-specific Tekay pool was the result of two bursts of amplification probably in the Miocene, with distinct patterns for the MA and SA repeatomes. This suggests a strong role of the Tekay elements as modulators of the genome-environment interaction in Erythrostemon, providing macroevolutionary insights about mechanisms of repeatome differentiation and plant diversification across space and time.

6.
Plant Cell Environ ; 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39254282

RESUMO

Polyploid varieties have been suggested as an alternative approach to promote drought tolerance in citrus crops. In this study, we compared the responses of diploid and tetraploid Sunki 'Tropical' rootstocks to water deficit when grafted onto 'Valencia' sweet orange trees and subjected to water withholding in isolation or competition experiments under potted conditions. Our results revealed that, when grown in isolation, tetraploid rootstocks took longer to show drought symptoms, but this advantage disappeared when grown in competition under the same soil moisture conditions. The differences in drought responses were mainly associated with variations in endogenous leaf levels of abscisic acid (ABA), hydrogen peroxide (H2O2) and carbohydrates among treatments. Overall, tetraploids were more affected by drought in individual experiments, showing higher H2O2 production, and in competition experiments, rapidly increasing ABA production to regulate stomatal closure and reduce water loss through transpiration. Therefore, our results highlight the crucial importance of evaluating diploid and tetraploid rootstocks under the same soil moisture conditions to better simulate field conditions, providing important insights to improve selection strategies for more resilient citrus rootstocks.

7.
Audiol Neurootol ; : 1-7, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38768568

RESUMO

INTRODUCTION: This study aimed to verify the influence of speech stimulus presentation and speed on auditory recognition in cochlear implant (CI) users with poorer performance. METHODS: The cross-sectional observational study applied auditory speech perception tests to fifteen adults, using three different ways of presenting the stimulus, in the absence of competitive noise: monitored live voice (MLV); recorded speech at typical speed (RSTS); recorded speech at slow speed (RSSS). The scores were assessed using the Percent Sentence Recognition Index (PSRI). The data were inferentially analysed using the Friedman and Wilcoxon tests with a 95% confidence interval and 5% significance level (p < 0.05). RESULTS: The mean age was 41.1 years, the mean duration of CI use was 11.4 years, and the mean hearing threshold was 29.7 ± 5.9 dBHL. Test performance, as determined by the PSRI, was MLV = 42.4 ± 17.9%; RSTS = 20.3 ± 14.3%; RSSS = 40.6 ± 20.7%. There was a significant difference identified for RSTS compared to MLV and RSSS. CONCLUSION: The way the stimulus is presented and the speed at which it is presented enable greater auditory speech recognition in CI users, thus favouring comprehension when the tests are applied in the MLV and RSSS modalities.

8.
Mol Phylogenet Evol ; 189: 107929, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37726037

RESUMO

Ameroglossum is a rare plant genus endemic to northeastern of Brazil, initially monospecific (A. pernambucense) and recently expanded by the description of eight new species and two related genera. The genus was initially placed in the family Scrophulariaceae, but this has never been phylogenetically tested. This group is ecologically restricted to rocky inselberg habitats that function as island-like systems (ILS) with spatial fragmentation, limited area, environmental heterogeneity, temporal isolation and low connectivity. Here we use a phylogenetic perspective to test the hypothesis that Ameroglossum diversification was related to island-like radiation in inselbergs. Our results support that Ameroglossum is monophyletic only with the inclusion of Catimbaua and Isabelcristinia (named here as Ameroglossum sensu lato) and this group was well-supported in the family Linderniaceae. Biogeographic analyses suggest that the ancestral of Ameroglossum and related genus arrived in South America c.a. 15 million years ago by long-distance dispersal, given the ancestral distribution of Linderniaceae in Africa. In rocky outcrop habitats, Ameroglossum s.l. developed floral morphological specialization associated with pollinating hummingbirds, compatible with an island-like model. However, no increase in speciation rate was detected, which may be related to high extinction rates and/or slow diversification rate in this ecologically restrictive environment. Altogether, in Ameroglossum key innovations involving flowers seem to have offered opportunities for evolution of greater phenotypic diversity and occupation of new niches in rocky outcrop environments.


Assuntos
Ecossistema , Lamiales , Filogenia , Flores/genética , Brasil
9.
Genetica ; 151(4-5): 311-321, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37566292

RESUMO

In the Neotropical region, one of the most diverse families of freshwater fishes is the monophyletic Serrasalmidae. Karyotypically, the family shows high diversity in chromosome numbers (2n = 54 to 64). However, little is discussed about whether the chromosomal changes are associated with cladogenetic events within this family. In the present study, we evaluated the role of chromosomal changes in the evolutionary diversification of Serrasalmidae. Our phylogenetic sampling included 36 species and revealed three main clades. The ancestral chromosome number reconstruction revealed the basic number 2n = 54 and a high frequency of ascending dysploid events in the most derived lineages. Our biogeographic reconstruction suggests an Amazonian origin of the family at 48-38 Mya, with independent colonization of other basins between 15 and 8 Mya. We did not find specific chromosomal changes or increased diversification rates correlated with the colonization of a new environment. On the other hand, an increase in the diversification rate was detected involving the genus Serrasalmus and Pygocentrus in the Miocene, correlated with the stasis of 2n = 60. Our data demonstrate that chromosomal rearrangements might have played an important evolutionary role in major cladogenetic events in Serrasalmidae, revealing them as a possible evolutionary driver in their diversification.


Assuntos
Caraciformes , Animais , Filogenia , Caraciformes/genética , Evolução Biológica , Especiação Genética , Cariótipo
10.
Ann Bot ; 131(5): 813-825, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36815646

RESUMO

BACKGROUND AND AIMS: Satellite DNAs (satDNAs) are repetitive sequences composed by tandemly arranged, often highly homogenized units called monomers. Although satDNAs are usually fast evolving, some satDNA families can be conserved across species separated by several millions of years, probably because of their functional roles in the genomes. Tyba was the first centromere-specific satDNA described for a holocentric organism, until now being characterized for only eight species of the genus Rhynchospora Vahl. (Cyperaceae). Here, we characterized Tyba across a broad sampling of the genus, analysing and comparing its evolutionary patterns with other satDNAs. METHODS: We characterized the structure and sequence evolution of satDNAs across a robust dadated phylogeny based on Hybrid Target-Capture Sequencing (hyb-seq) of 70 species. We mined the repetitive fraction for Tyba-like satellites to compare its features with other satDNAs and to construct a Tyba-based phylogeny for the genus. KEY RESULTS: Our results show that Tyba is present in the majority of examined species of the genus, spanning four of the five major clades and maintaining intrafamily pairwise identity of 70.9% over 31 Myr. In comparison, other satellite families presented higher intrafamily pairwise identity but are phylogenetically restricted. Furthermore, Tyba sequences could be divided into 12 variants grouped into three different clade-specific subfamilies, showing evidence of traditional models of satDNA evolution, such as the concerted evolution and library models. Besides, a Tyba-based phylogeny showed high congruence with the hyb-seq topology. Our results show structural indications of a possible relationship of Tyba with nucleosomes, given its high curvature peaks over conserved regions and overall high bendability values compared with other non-centromeric satellites. CONCLUSIONS: Overall, Tyba shows a remarkable sequence conservation and phylogenetic significance across the genus Rhynchospora, which suggests that functional roles might lead to long-term stability and conservation for satDNAs in the genome.


Assuntos
Cyperaceae , DNA Satélite , DNA Satélite/genética , Cyperaceae/genética , Filogenia , Centrômero/genética , Sequências Repetitivas de Ácido Nucleico , Evolução Molecular
11.
J Oral Pathol Med ; 52(10): 961-970, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37783225

RESUMO

BACKGROUND: Oral squamous cell carcinoma is characterized by high rates of morbidity and mortality. Evidence obtained for different types of cancer shows that tumor initiation, progression, and therapeutic resistance are regulated by heat shock factor 1. This research aimed to analyze the effects of heat shock factor 1 on the biological behavior of oral squamous cell carcinoma. METHODS: Clinicopathological and immunoexpression study of heat shock factor 1 in 70 cases of oral tongue SCC and functional assays by gene silencing of this factor in an oral tongue SCC cell line. RESULTS: Heat shock factor 1 was overexpressed in oral tongue SCC specimens compared to normal oral mucosa (p < 0.0001) and in the SCC15 line compared to immortalized keratinocytes (p < 0.005). No significant associations were observed between overexpression of heat shock factor 1 and clinicopathological parameters or survival rates of the oral tongue SCC cases in the present sample. In vitro experiments showed that heat shock factor 1 silencing inhibited cell proliferation (p < 0.005) and cell cycle progression, with the accumulation of cells in the G0/G1 phase (p < 0.01). In addition, heat shock factor 1 silencing reduced cell invasion capacity (p < 0.05) and epithelial-mesenchymal transition, characterized by a decrease in vimentin expression (p < 0.05) and an increase in E-cadherin expression (p < 0.001). CONCLUSION: Heat shock factor 1 may exert several functions that help maintain cell stability under the stressful conditions of the tumor microenvironment. Thus, strategies targeting the regulation of this protein may in the future be a useful therapeutic tool to control the progression of oral squamous cell carcinoma.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Neoplasias da Língua , Humanos , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Resposta ao Choque Térmico , Neoplasias Bucais/patologia , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Neoplasias da Língua/patologia , Microambiente Tumoral
12.
J Phys Chem A ; 127(14): 3096-3103, 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37017103

RESUMO

Sequential quantum mechanics/molecular mechanics (QM/MM) calculations combining the average solvent electrostatic configuration (ASEC) and the free energy gradient method are employed to locate minimum structures of α- and ß-alanine in a water environment. Herein, we study the solvation effects in the nuclear magnetic resonance (NMR) spectroscopy, vibrational circular dichroism (VCD) spectroscopy, and electronic circular dichroism (ECD) spectroscopy of dl-α-alanine and ß-alanine molecules. Our results point out that the ASEC-FEG (average solvent electrostatic configuration with the free energy gradient) method is a suitable approach for finding equilibrium structures of the alanine molecules in aqueous solution. Its accuracy is checked by comparing the optimized structures with those reached by the polarizable continuum model (PCM) and via experimental data. NMR parameters and vibrational and electronic UV-vis spectra are computed with a remarkable agreement with their corresponding experimental values.

13.
J Phys Chem A ; 127(3): 619-626, 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36648308

RESUMO

Within the framework of Density Functional Theory (DFT), the relevance of the term Hartree-Fock exchange (HFE) for a variety of molecular properties is a critical point. For this reason, we spend efforts to understand these relationships in nuclear magnetic resonance (NMR) parameters in a water solvent. This work takes advantage of the appropriate aug-cc-pVTZ-J basis set and the Minnesota family of DFT methods, which consider different portions of HFE contributions. With regard to solvent participation, the results are based on a sequential Monte Carlo/Quantum Mechanics procedure, which builds the structures of the liquid under realistic thermodynamic conditions. Compared to the accurate results of second-order polarization propagator approximation (SOPPA) and experimental data, all NMR parameters show a huge dependence on the size of the HFE contribution. For instance, the inclusion of this term in 1JOH and 2JHH indirect spin-spin couplings does vary with 49.661 and 25.459 Hz, respectively. The M06-HF method accounts for 100% of HFE and better matches the σO and σH shielding constants. On the other hand, 1JOH and 2JHH demand a medium contribution (54% of HFE), the best description being associated with the M06-2X method. Thus, the dependence varies regarding the phenomenology of the property in focus and the order for independent treatments. For elements that participate in hydrogen bonds simultaneously as donor and acceptor actors, the results indicate that explicit solvent molecules must be considered in the quantum mechanical calculations for better modeling of paramagnetic shielding constants.

14.
J Thromb Thrombolysis ; 55(2): 339-345, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36401731

RESUMO

The use of direct oral anticoagulants (DOACs) is widely increasing in the United States (US). Warfarin has been the conventional anticoagulant used in the past few decades, but it has been gradually replaced by DOACs. The objective of the study was to analyze trends in utilization, reimbursement, and price for those anticoagulants in the US Medicaid population. Retrospective data analysis was conducted using the National Summary Files for the Medicaid State Drug Utilization Data. Study drugs included dabigatran, rivaroxaban, apixaban, edoxaban and warfarin. The study assessed secular trends of utilization, reimbursement, and per-prescription price. The data was collected from the first quarter of 2000 through to the second quarter of 2020 restricted for outpatient prescriptions only. During the 21-year study period, a substantial rise in total expenditures on warfarin and DOACs was observed from $144 million in 2000 to $694 million in 2020. Moreover, the utilization of DOACs has increased significantly since the first approval of Xarelto in 2010 from 1079 in 2011 to 1.5 million in 2019. The per-prescription price of DOACs increased from an average of $200 in 2011 to $407 in 2020. Conversely, the total number of prescriptions of Warfarin and branded Coumadin decreased from 2.4 million to 1.4 million and from 3.9 million to less than a million, respectively. The present study demonstrated a change in the trends of US expenditure and utilization for warfarin and DOACs with DOACs representing the majority of market share of both spending per prescription and reimbursement.


Assuntos
Fibrilação Atrial , Varfarina , Humanos , Estados Unidos , Varfarina/uso terapêutico , Medicaid , Estudos Retrospectivos , Anticoagulantes/uso terapêutico , Rivaroxabana/uso terapêutico , Dabigatrana/uso terapêutico , Administração Oral , Fibrilação Atrial/tratamento farmacológico
15.
MAGMA ; 35(1): 17-27, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34910266

RESUMO

OBJECTIVE: To evaluate the feasibility of intravoxel incoherent motion (IVIM) in assessing blood-brain barrier (BBB) integrity and microvasculature in tumoral tissue of glioma patients. METHODS: Images from 8 high-grade and 4 low-grade glioma patients were acquired on a 3 T MRI scanner. Acquisition protocol included pre- and post-contrast T1- and T2-weighted imaging, FLAIR, dynamic susceptibility contrast (DSC), and susceptibility-weighted imaging (SWI). In addition, IVIM was acquired with 15 b-values and fitted under the non-negative least square (NNLS) model to output the diffusion (D) and pseudo-diffusion (D*) coefficients, perfusion fraction (f), and f times D* (fD*) maps. RESULTS: IVIM perfusion-related maps were sensitive to (1) blood flow and perfusion alterations within the microvasculature of brain tumors, in agreement with intra-tumoral susceptibility signal (ITSS); (2) enhancing areas of BBB breakdown in agreement with DSC maps as well as areas of BBB abnormality that was not detected on DSC maps; (3) enhancing perfusion changes within edemas; (4) detecting early foci of increased perfusion within low-grade gliomas. CONCLUSION: The results suggest IVIM may be a promising approach to delineate tumor extension and progression in size, and to predict histological grade, which are clinically relevant information that characterize tumors and guide therapeutic decisions in patients with glioma.


Assuntos
Barreira Hematoencefálica , Glioma , Microvasos , Barreira Hematoencefálica/diagnóstico por imagem , Barreira Hematoencefálica/patologia , Barreira Hematoencefálica/fisiopatologia , Imagem de Difusão por Ressonância Magnética/métodos , Estudos de Viabilidade , Glioma/irrigação sanguínea , Glioma/diagnóstico por imagem , Glioma/patologia , Glioma/fisiopatologia , Humanos , Microcirculação , Microvasos/diagnóstico por imagem , Microvasos/patologia , Movimento (Física)
16.
Ann Bot ; 128(7): 835-848, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34050647

RESUMO

BACKGROUND AND AIMS: With the advance of high-throughput sequencing, reduced-representation methods such as target capture sequencing (TCS) emerged as cost-efficient ways of gathering genomic information, particularly from coding regions. As the off-target reads from such sequencing are expected to be similar to genome skimming (GS), we assessed the quality of repeat characterization in plant genomes using these data. METHODS: Repeat composition obtained from TCS datasets of five Rhynchospora (Cyperaceae) species were compared with GS data from the same taxa. In addition, a FISH probe was designed based on the most abundant satellite found in the TCS dataset of Rhynchospora cephalotes. Finally, repeat-based phylogenies of the five Rhynchospora species were constructed based on the GS and TCS datasets and the topologies were compared with a gene-alignment-based phylogenetic tree. KEY RESULTS: All the major repetitive DNA families were identified in TCS, including repeats that showed abundances as low as 0.01 % in the GS data. Rank correlations between GS and TCS repeat abundances were moderately high (r = 0.58-0.85), increasing after filtering out the targeted loci from the raw TCS reads (r = 0.66-0.92). Repeat data obtained by TCS were also reliable in developing a cytogenetic probe of a new variant of the holocentromeric satellite Tyba. Repeat-based phylogenies from TCS data were congruent with those obtained from GS data and the gene-alignment tree. CONCLUSIONS: Our results show that off-target TCS reads can be recycled to identify repeats for cyto- and phylogenomic investigations. Given the growing availability of TCS reads, driven by global phylogenomic projects, our strategy represents a way to recycle genomic data and contribute to a better characterization of plant biodiversity.


Assuntos
Genoma de Planta , Sequenciamento de Nucleotídeos em Larga Escala , DNA , Genoma de Planta/genética , Filogenia , Análise de Sequência de DNA
17.
Plant Cell Rep ; 40(8): 1377-1393, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33074436

RESUMO

KEY MESSAGE: The tomato mutant Never ripe (Nr), a loss-of-function for the ethylene receptor SlETR3, shows enhanced growth, associated with increased carbon assimilation and a rewiring of the central metabolism. Compelling evidence has demonstrated the importance of ethylene during tomato fruit development, yet its role on leaf central metabolism and plant growth remains elusive. Here, we performed a detailed characterization of Never ripe (Nr) tomato, a loss-of-function mutant for the ethylene receptor SlETR3, known for its fruits which never ripe. However, besides fruits, the Nr gene is also constitutively expressed in vegetative tissues. Nr mutant showed a growth enhancement during both the vegetative and reproductive stage, without an earlier onset of leaf senescence, with Nr plants exhibiting a higher number of leaves and an increased dry weight of leaves, stems, roots, and fruits. At metabolic level, Nr also plays a significant role with the mutant showing changes in carbon assimilation, carbohydrates turnover, and an exquisite reprogramming of a large number of metabolite levels. Notably, the expression of genes related to ethylene signaling and biosynthesis are not altered in Nr. We assess our results in the context of those previously published for tomato fruits and of current models of ethylene signal transduction, and conclude that ethylene insensitivity mediated by Nr impacts the whole central metabolism at vegetative stage, leading to increased growth rates.


Assuntos
Etilenos/metabolismo , Proteínas de Plantas/genética , Solanum lycopersicum/fisiologia , Carbono/metabolismo , Frutas/genética , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Solanum lycopersicum/genética , Solanum lycopersicum/crescimento & desenvolvimento , Mutação , Fotossíntese , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Transdução de Sinais , Amido/metabolismo , Sacarose/metabolismo
18.
BMC Womens Health ; 21(1): 174, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33892709

RESUMO

BACKGROUND: Human papillomavirus (HPV) and Trichomonas vaginalis (TV) infections are the most common sexually transmitted infections (STIs) globally. The latter has contributed to a variety of adverse outcomes for both sexes. Moreover, in Brazil, epidemiological studies on patients with STIs are limited. Therefore, this study aimed to determine the prevalence of TV and its association with HPV in women undergoing cervical cancer screening. METHODS: Women with a normal cervix were recruited from a community-based cervical cancer screening program. Gynecological examinations were conducted, and questionnaires were provided. Vaginal canal and uterine cervix samples were collected for cytological examinations (reported using the 2001 Bethesda System) and tested for the presence of TV and HPV DNA. RESULTS: In total, 562 women who attended public primary healthcare were included in the study. The T. vaginalis was present in 19.0% (107) and HPV DNA was present in 46.8% (263) of women. Among the women of TV 73.8% (79) had a co-infection with HPV (p = 0.001). CONCLUSIONS: We concluded that a TV infection is associated with an HPV infection of the cervix as well as with the cervical cytological abnormalities. Further studies could reveal the mechanisms by which these two organisms interact at the cellular level, with control for shared behavioral risk factors.


Assuntos
Alphapapillomavirus , Infecções por Papillomavirus , Trichomonas vaginalis , Neoplasias do Colo do Útero , Brasil , Detecção Precoce de Câncer , Feminino , Humanos , Masculino , Papillomaviridae/genética , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/epidemiologia , Prevalência , Fatores de Risco
19.
J Therm Biol ; 97: 102881, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33863445

RESUMO

This study aimed to evaluate the use of thermal imaging obtained by infrared thermography (IRT) to detect cases of subclinical mastitis in dairy cows under commercial conditions of compost barn systems in a region of Brazil with a semiarid climate. Twenty-eight crossbred cows were evaluated twice a day for one week using IRT. Three thermal images were obtained for each cow, referring to the anatomical regions of the right and left fore udder and rear udder. A computer program was used to analyze the images and obtain the right fore udder temperature (RFUT, °C), left fore udder temperature (LFUT, °C), rear udder temperature (RUT, °C), and average udder temperature (AUT, °C). In addition, samples of milk from each quarter of the udder were collected for somatic cell count (SCC) to correlate the diseases observed on the thermal image with any infection in the udder region. The results obtained using IRT were subjected to regression and correlation analyses. It was observed that LFUT, RAQT, RUT, and AUT were adjusted in quadratic polynomial models with good prediction of SCC (i.e., infection) with R2 = 0.92, 0.97, 0.86, and 0.94, respectively. The region of the anterior quarters of the udder was the most promising for imaging, stronger correlations were obtained between LFUT and RFUT with SCC (r = 0.87 and 0.88, respectively). The IRT is a practical technology capable of detecting cases of mastitis in dairy cows with good precision, especially with thermal images from the anatomical region of the front quarters of the udder. However, more detailed studies are needed to make thermal imaging processing a more useful method for routine activities on farms in compost barn systems.


Assuntos
Mastite/diagnóstico , Termografia , Animais , Temperatura Corporal , Bovinos , Contagem de Células/veterinária , Compostagem , Feminino , Abrigo para Animais , Raios Infravermelhos , Glândulas Mamárias Animais/fisiologia , Mastite/veterinária , Leite/citologia
20.
Ecotoxicol Environ Saf ; 195: 110449, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32220791

RESUMO

Environmental pollutants affect fish species differently because their routes of exposure make them more critical to a specific group regarding foraging habits or food preferences. However, the association between local problems and environmental conditions makes a particular species more suitable for use in monitoring programs. Thus, this study compared muscle accumulation of metals (Al, Ba, Cr, Cu, Fe, Mn, Ti and Zn) and toxicogenetic damage to three neotropical species from the Itapemirim River Basin (Brazil) with distinct foraging habits and feeding preferences: Geophagus brasiliensis (benthopelagic - omnivorous); Harttia sp. (benthic - detritivorous); and Leporinus copellandii (pelagic - omnivorous). There was seasonal influence on muscle metal concentrations: Ba and Mn concentrations in G. brasiliensis, Cr in Harttia sp. and Zn, Al and Fe in L. copellandii increased during the rainy season. G. brasiliensis was the most sensitive species, since it had a statistically higher prevalence of erythrocytic nuclear abnormalities, which was influenced by seasonality. This result might be an effect of its benthopelagic habits, which favors contact with a larger group of contaminants due to its interaction with both water column and sediment. The present study showed the differential sensitivity of fish species and that the combination of chemical analysis of pollutants with evaluation of toxicogenetic responses helps to choose the best species for field studies.


Assuntos
Peixes/metabolismo , Metais/metabolismo , Metais/toxicidade , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Brasil , Ciclídeos/metabolismo , Dano ao DNA , Monitoramento Ambiental , Comportamento Alimentar , Peixes/fisiologia , Músculos/metabolismo , Rios
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