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1.
J Exp Bot ; 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39113673

RESUMO

Successful plant reproduction depends on the adequate development of flower organs controlled by cell proliferation and other processes. The SCI1 gene regulates cell proliferation and affects the final size of the female reproductive organ. To unravel the molecular mechanism exerted by SCI1 in cell proliferation control, we searched for its interaction partners through semi-in vivo pulldown experiments, uncovering a cyclin-dependent kinase, NtCDKG;2. Bimolecular fluorescence complementation (BiFC) and co-localization experiments showed that SCI1 interacts with NtCDKG;2 and its cognate NtCyclin L in nucleoli and splicing speckles. The screening of a yeast two-hybrid (Y2H) cDNA library using SCI1 as bait revealed a novel DEAD-box RNA helicase (NtRH35). The interaction between the NtCDKG;2-NtCyclin L complex, and NtRH35 was also shown. Subcellular localization experiments showed that SCI1, NtRH35, and the NtCDKG;2-NtCyclin L complex associate with each other within splicing speckles. The Y2H screening of NtCDKG;2 and NtRH35 identified the conserved spliceosome components U2a', NKAP, and CACTIN. This work presents SCI1 and its interactors NtCDKG;2-NtCyclin L complex, and NtRH35 as new spliceosome-associated proteins. Our findings reveal a network of interactions and suggest that SCI1 may regulate cell proliferation through the splicing process. This study provides new valuable insights into the intricate molecular pathways governing plant development.

2.
Sci Rep ; 14(1): 17219, 2024 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-39060371

RESUMO

Fire plays a key role in grasslands, determining the distribution and evolution of species and boundaries with neighboring ecosystems. Evidence of community-wide responses to fire is largely based on taxonomic and functional descriptors, while the phylogenetic dimension is overlooked. Here we evaluated how the taxonomic and phylogenetic structure of grassland plant communities responded to a time since fire (TSF) gradient. We sampled 12 communities in Southern Brazil under varying TSF and calculated taxonomic species richness (S) and dominance (D), phylogenetic diversity (PD), and mean phylogenetic distances (MPD). We used Structural Equation Models to test the relationships between the environmental gradient and community descriptors. Communities with longer TSF presented higher PD and MPD but lower species richness and increased taxonomic dominance. These sites were dominated by monocots, specifically C4 grasses, but also presented exclusive clades, whereas recently-burned sites presented lower taxonomic dominance and more species distributed in a wider variety of clades. Our results indicate that these scenarios are interchangeable and dependent on fire management. Fire adaptation was not constrained by phylogenetic relatedness, contrasting with previous findings for tropical savannahs and indicating that temperate and tropical non-forest ecosystems from South America respond differently to fire, possibly due to different evolutionary histories.


Assuntos
Biodiversidade , Incêndios , Pradaria , Filogenia , Brasil , Plantas/classificação , Plantas/genética , Poaceae/genética , Poaceae/classificação , Ecossistema
3.
Heredity (Edinb) ; 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39039117

RESUMO

Neotropical fishes exhibit remarkable karyotype diversity, whose evolution is poorly understood. Here, we studied genetic differences in 60 individuals, from 11 localities of one species, the wolf fish Hoplias malabaricus, from populations that include six different "karyomorphs". These differ in Y-X chromosome differentiation, and, in several cases, by fusions with autosomes that have resulted in multiple sex chromosomes. Other differences are also observed in diploid chromosome numbers and morphologies. In an attempt to start understanding how this diversity was generated, we analyzed within- and between-population differences in a genome-wide sequence data set. We detect clear genotype differences between karyomorphs. Even in sympatry, samples with different karyomorphs differ more in sequence than samples from allopatric populations of the same karyomorph, suggesting that they represent populations that are to some degree reproductively isolated. However, sequence divergence between populations with different karyomorphs is remarkably low, suggesting that chromosome rearrangements may have evolved during a brief evolutionary time. We suggest that the karyotypic differences probably evolved in allopatry, in small populations that would have allowed rapid fixation of rearrangements, and that they became sympatric after their differentiation. Further studies are needed to test whether the karyotype differences contribute to reproductive isolation detected between some H. malabaricus karyomorphs.

5.
J Appl Oral Sci ; 32: e20230374, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38922240

RESUMO

OBJECTIVES: to evaluate the morphological and functional characteristics of the peri-implant bone tissue that was formed during the healing process by the placement implants using two different surface treatments: hydrophilic Acqua™ (ACQ) and rough NeoPoros™ (NEO), in spontaneously hypertensive (SHR) and normotensive rats (Wistar) whether or not treated with losartan. METHODOLOGY: In total, 96 male rats (48 Wistar and 48 SHR) were divided into eight subgroups: absolute control rough (COA NEO), absolute control hydrophilic (COA ACQ), losartan control rough (COL NEO), losartan control hydrophilic (COL ACQ), SHR absolute rough (SHR NEO), SHR absolute hydrophilic (SHR ACQ), SHR losartan rough (SHRL NEO), and SHR losartan hydrophilic (SHRL ACQ). The rats medicated with losartan received daily doses of the medication. NeoPoros™ and Acqua™ implants were installed in the tibiae of the rats. After 14 and 42 days of the surgery, the fluorochromes calcein and alizarin were injected in the rats. The animals were euthanized 67 days after treatment. The collected samples were analyzed by immunohistochemistry, biomechanics, microcomputerized tomography, and laser confocal scanning microscopy analysis. RESULTS: The osteocalcin (OC) and vascular endothelium growth factor (VEGF) proteins had moderate expression in the SHRL ACQ subgroup. The same subgroup also had the highest implant removal torque. Regarding microarchitectural characteristics, a greater number of trabeculae was noted in the control animals that were treated with losartan. In the bone mineralization activity, it was observed that the Acqua™ surface triggered higher values of MAR (mineral apposition rate) in the COA, COL, and SHRL groups (p<0.05). CONCLUSION: the two implant surface types showed similar responses regarding the characteristics of the peri-implant bone tissue, even though the ACQ surface seems to improve the early stages of osseointegration.


Assuntos
Implantes Dentários , Losartan , Ratos Endogâmicos SHR , Ratos Wistar , Propriedades de Superfície , Microtomografia por Raio-X , Animais , Losartan/farmacologia , Masculino , Propriedades de Superfície/efeitos dos fármacos , Fatores de Tempo , Reprodutibilidade dos Testes , Imuno-Histoquímica , Interações Hidrofóbicas e Hidrofílicas , Osseointegração/efeitos dos fármacos , Resultado do Tratamento , Implantação Dentária Endóssea/métodos , Microscopia Confocal , Tíbia/efeitos dos fármacos , Tíbia/cirurgia , Análise de Variância , Fenômenos Biomecânicos , Valores de Referência , Osteocalcina/análise
7.
Am Heart J Plus ; 40: 100373, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38510503

RESUMO

Study objective: To evaluate the cost-effectiveness of EtCO2 monitoring during in-hospital cardiorespiratory arrest (CA) care outside the intensive care unit (ICU) and emergency room department. Design: We performed a cost-effectiveness analysis based on a simple decision model cost analysis and reported the study using the CHEERS checklist. Model inputs were derived from a retrospective Brazilian cohort study, complemented by information obtained through a literature review. Cost inputs were gathered from both literature sources and contacts with hospital suppliers. Setting: The analysis was carried out from the perspective of a tertiary referral hospital in a middle-income country. Participants: The study population comprised individuals experiencing in-hospital CA who received cardiopulmonary resuscitation (CPR) by rapid response team (RRT) in a hospital ward, not in the ICU or emergency room department. Interventions: Two strategies were assumed for comparison: one with an RRT delivering care without capnography during CPR and the other guiding CPR according to the EtCO2 waveform. Main outcome measures: Incremental cost-effectiveness rate (ICER) to return of spontaneous circulation (ROSC), hospital discharge, and hospital discharge with good neurological outcomes. Results: The ICER for EtCO2 monitoring during CPR, resulting in an absolute increase of one more case with ROSC, hospital discharge, and hospital discharge with good neurological outcome, was calculated at Int$ 515.78 (361.57-1201.12), Int$ 165.74 (119.29-248.4), and Int$ 240.55, respectively. Conclusion: In managing in-hospital CA in the hospital ward, incorporating EtCO2 monitoring is likely a cost-effective measure within the context of a middle-income country hospital with an RRT.

8.
J. appl. oral sci ; 32: e20230374, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1564709

RESUMO

Abstract Hypertensive individuals present alterations in their calcium metabolism that consequently decrease the concentration of this mineral in the bone tissue. Objectives to evaluate the morphological and functional characteristics of the peri-implant bone tissue that was formed during the healing process by the placement implants using two different surface treatments: hydrophilic Acqua™ (ACQ) and rough NeoPoros™ (NEO), in spontaneously hypertensive (SHR) and normotensive rats (Wistar) whether or not treated with losartan. Methodology In total, 96 male rats (48 Wistar and 48 SHR) were divided into eight subgroups: absolute control rough (COA NEO), absolute control hydrophilic (COA ACQ), losartan control rough (COL NEO), losartan control hydrophilic (COL ACQ), SHR absolute rough (SHR NEO), SHR absolute hydrophilic (SHR ACQ), SHR losartan rough (SHRL NEO), and SHR losartan hydrophilic (SHRL ACQ). The rats medicated with losartan received daily doses of the medication. NeoPoros™ and Acqua™ implants were installed in the tibiae of the rats. After 14 and 42 days of the surgery, the fluorochromes calcein and alizarin were injected in the rats. The animals were euthanized 67 days after treatment. The collected samples were analyzed by immunohistochemistry, biomechanics, microcomputerized tomography, and laser confocal scanning microscopy analysis. Results The osteocalcin (OC) and vascular endothelium growth factor (VEGF) proteins had moderate expression in the SHRL ACQ subgroup. The same subgroup also had the highest implant removal torque. Regarding microarchitectural characteristics, a greater number of trabeculae was noted in the control animals that were treated with losartan. In the bone mineralization activity, it was observed that the Acqua™ surface triggered higher values of MAR (mineral apposition rate) in the COA, COL, and SHRL groups (p<0.05). Conclusion the two implant surface types showed similar responses regarding the characteristics of the peri-implant bone tissue, even though the ACQ surface seems to improve the early stages of osseointegration.

9.
Nat Commun ; 14(1): 5367, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37666834

RESUMO

Motivated by the recent report of room-temperature superconductivity at near-ambient pressure in N-doped lutetium hydride, we performed a comprehensive, detailed study of the phase diagram of the Lu-N-H system, looking for superconducting phases. We combined ab initio crystal structure prediction with ephemeral data-derived interatomic potentials to sample over 200,000 different structures. Out of the more than 150 structures predicted to be metastable within ~50 meV from the convex hull we identify 52 viable candidates for conventional superconductivity, for which we computed their superconducting properties from Density Functional Perturbation Theory. Although for some of these structures we do predict a finite superconducting Tc, none is even remotely compatible with room-temperature superconductivity as reported by Dasenbrock et al. Our work joins the broader community effort that has followed the report of near-ambient superconductivity, confirming beyond reasonable doubt that no conventional mechanism can explain the reported Tc in Lu-N-H.

10.
Health Qual Life Outcomes ; 21(1): 87, 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37568236

RESUMO

BACKGROUND: In Brazil, cancer patients and caregivers of cancer patients seek judicial intervention for free access to medications from the public health system. Indeed, the COVID-19 pandemic potentially affected the health-related quality of life of cancer patients and caregivers of cancer patients. This study aimed to describe the sociodemographic profile and assess the health-related quality of life of patients and caregivers in the state of Goias, Brazil, in 2020. METHODS: A cross-sectional study was conducted using the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36) and a sociodemographic questionnaire. RESULTS: A total of 88 (67,7%) patients and 42 (32,3%) caregivers participated in the study, mostly women (55,5%); aged from 18 to 60 (66%) years old; with up to nine years of education (73,1%) and monthly family income lower than the minimum wage (69,2%); married or in a stable union (92,3%); living with multiple people in the same household (73,8%). The quality of life domains with the best scores were mental health for patients and pain for caregivers. The most affected quality of life domain was physical limitation for patients and caregivers. Factors associated with better quality of life were female gender and age between 18 and 60 years in patients, more than 9 years of education, living with multiple people in the same house, and having a monthly family income higher than US$200 for caregivers. CONCLUSION: The study found evidence of physical and emotional vulnerability during the pandemic, highlighting the need to strengthen public policies of assistance support to this population.


Assuntos
COVID-19 , Neoplasias , Humanos , Feminino , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Masculino , Qualidade de Vida/psicologia , Pandemias , Cuidadores/psicologia , Estudos Transversais , COVID-19/epidemiologia
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