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1.
Philos Trans R Soc Lond B Biol Sci ; 379(1907): 20230139, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-38913066

RESUMO

One of the fundamental aims of ecological, epidemiological and evolutionary studies of host-parasite interactions is to unravel which factors affect parasite virulence. Theory predicts that virulence and transmission are correlated by a trade-off, as too much virulence is expected to hamper transmission owing to excessive host damage. Coinfections may affect each of these traits and/or their correlation. Here, we used inbred lines of the spider mite Tetranychus urticae to test how coinfection with T. evansi impacted virulence-transmission relationships at different conspecific densities. The presence of T. evansi on a shared host did not change the relationship between virulence (leaf damage) and the number of transmitting stages (i.e. adult daughters). The relationship between these traits was hump-shaped across densities, both in single and coinfections, which corresponds to a trade-off. Moreover, transmission to adjacent hosts increased in coinfection, but only at low T. urticae densities. Finally, we tested whether virulence and the number of daughters were correlated with measures of transmission to adjacent hosts, in single and coinfections at different conspecific densities. Traits were mostly independent, meaning that interspecific competitors may increase transmission without affecting virulence. Thus, coinfections may impact epidemiology and parasite trait evolution, but not necessarily the virulence-transmission trade-off.This article is part of the theme issue 'Diversity-dependence of dispersal: interspecific interactions determine spatial dynamics'.


Assuntos
Coinfecção , Interações Hospedeiro-Parasita , Tetranychidae , Animais , Virulência , Tetranychidae/fisiologia , Coinfecção/parasitologia , Coinfecção/transmissão , Feminino
2.
J Neurooncol ; 167(2): 267-273, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38349476

RESUMO

PURPOSE: High-grade gliomas (HGG) are aggressive cancers, and their recurrence is inevitable, despite advances in treatment options. While repeated tumor resection has been shown to increase survival rate, its impact on quality of life is not clearly defined. To address this gap, we compared quality of life (QoL) changes in HGG patients who underwent first-time (FTR) versus repeat surgical resections (RSR) for management of recurrence. METHODS: Forty-four adults with HGG who underwent tumor resection were included in this study and classified into either the FTR group (n = 23) or the RSR group (n = 21). All patients completed comprehensive neuropsychological evaluations that included the Functional Assessment of Cancer Therapy-General (FACT-G) and Functional Assessment of Cancer Therapy-Cognitive Function (FACT-Cog) scales, pre-operatively and at two weeks post-operatively. RESULTS: There was no difference between the FTR and RSR groups in any of the QoL indices (all p > .05), except for improved emotional well-being and worsened social well-being, suggesting minimal detrimental effects of repeat surgeries on QoL in comparison to first time surgery. CONCLUSIONS: These results suggest that repeated resection is a viable strategy in certain cases for management of HGG recurrence, with similar impact on QoL as observed in patients undergoing first time surgery. These encouraging outcomes provide useful insight to guide treatment strategies and patient and clinician decision making to optimize surgical and functional outcomes.


Assuntos
Neoplasias Encefálicas , Glioma , Adulto , Humanos , Neoplasias Encefálicas/patologia , Qualidade de Vida , Glioma/patologia , Reoperação
3.
J Evol Biol ; 37(6): 631-641, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38279952

RESUMO

Metal accumulation is used by some plants as a defence against herbivores. Yet, herbivores may adapt to these defences, becoming less susceptible. Moreover, ecosystems often contain plants that do and do not accumulate metals, but whether such heterogeneity affects herbivore adaptation remains understudied. Here, we performed experimental evolution to test whether the spider mite Tetranychus evansi adapts to plants with high cadmium concentrations, in homogeneous (plants with cadmium) or heterogeneous (plants with or without cadmium) environments. For that we used tomato plants, which accumulate cadmium, thus affecting the performance of these spider mites. We measured mite fecundity, hatching rate, and the number of adult offspring after 12 and 33 generations and habitat choice after 14 and 51 generations, detecting no trait change, which implies the absence of adaptation. We then tested whether this was due to a lack of genetic variation in the traits measured and, indeed, additive genetic variance was low. Interestingly, despite no signs of adaptation, we observed a decrease in fecundity and number of adult offspring produced on cadmium-free plants, in the populations evolving in environments with cadmium. Therefore, evolving in environments with cadmium reduces the growth rate of spider mite populations on non-accumulating plants. Possibly, other traits contributed to population persistence on plants with cadmium. This calls for more studies addressing herbivore adaptation to plant metal accumulation.


Assuntos
Cádmio , Herbivoria , Tetranychidae , Animais , Tetranychidae/fisiologia , Tetranychidae/genética , Cádmio/metabolismo , Solanum lycopersicum , Adaptação Fisiológica , Fertilidade , Feminino
4.
World Neurosurg ; 182: e34-e44, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37952880

RESUMO

BACKGROUND: Intramedullary spinal cord tumors are challenging to resect, and their postoperative neurological outcomes are often difficult to predict, with few studies assessing this outcome. METHODS: We reviewed the medical records of all patients surgically treated for Intramedullary spinal cord tumors at our multisite tertiary care institution (Mayo Clinic Arizona, Mayo Clinic Florida, Mayo Clinic Rochester) between June 2002 and May 2020. Variables that were significant in the univariate analyses were included in a multivariate logistic regression. "MissForest" operating on the Random Forest algorithm, was used for data imputation, and K-prototype was used for data clustering. Heatmaps were added to show correlations between postoperative neurological deficit and all other included variables. Shapley Additive exPlanations were implemented to understand each feature's importance. RESULTS: Our query resulted in 315 patients, with 160 meeting the inclusion criteria. There were 53 patients with astrocytoma, 66 with ependymoma, and 41 with hemangioblastoma. The mean age (standard deviation) was 42.3 (17.5), and 48.1% of patients were women (n = 77/160). Multivariate analysis revealed that pathologic grade >3 (OR = 1.55; CI = [0.67, 3.58], P = 0.046 predicted a new neurological deficit. Random Forest algorithm (supervised machine learning) found age, use of neuromonitoring, histology of the tumor, performing a midline myelotomy, and tumor location to be the most important predictors of new postoperative neurological deficits. CONCLUSIONS: Tumor grade/histology, age, use of neuromonitoring, and myelotomy type appeared to be most predictive of postoperative neurological deficits. These results can be used to better inform patients of perioperative risk.


Assuntos
Astrocitoma , Ependimoma , Hemangioblastoma , Neoplasias da Medula Espinal , Humanos , Feminino , Masculino , Neoplasias da Medula Espinal/patologia , Procedimentos Neurocirúrgicos/efeitos adversos , Procedimentos Neurocirúrgicos/métodos , Astrocitoma/cirurgia , Ependimoma/cirurgia , Ependimoma/patologia , Hemangioblastoma/cirurgia , Medula Espinal/patologia , Estudos Retrospectivos , Resultado do Tratamento , Estudos Multicêntricos como Assunto
5.
ACS Biomater Sci Eng ; 9(12): 6870-6879, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37943794

RESUMO

Dermatomycoses are typical hair, skin, or nail infections caused mainly by dermatophytes and nondermatophytes: Trichophyton, Microsporum, Epidermophyton, and Candida. In addition to the esthetical impact, pain, and nail deformity, these mycoses can be a source of severe disease. The high cost of treatment, toxicity, and the emergence of resistant infectious agents justifies research into new drugs. This work evaluates the fungicidal activity of nanocomposites (NCs) based on reduced graphene oxide (rGO) loaded with silver (Ag) nanoparticles (rGO/Ag) against clinical isolates of dermatophytes and Candida species. This is an unprecedented study in which, for the first time, hybrid nanocompounds based on Ag/rGO were tested against Epidermophytom, Microsporum, and Trichophyton species (dermatophytes agents). In this paper, we synthesize rGO using different concentrations of Ag by hydrolysis of metal salt AgNO3 and follow the growth of nanocrystals on sheets of rGO provided by the NaBH4. The NCs were analyzed by X-ray diffraction analysis, and the NC morphology, silver distribution on the rGO surface, and crystalline information were investigated by transmission electron microscopy. Antifungal susceptibility assay was performed by the microdilution method based on modified Clinical and Laboratory Standards Institute (CLSI) protocol. Time-kill kinetics was conducted to monitor the effect of the composite to inhibit fungal cells or promote structural changes, avoiding germination. The toxicological evaluation of the NCs was born in an in vivo model based on Galleria mellonella (G. mellonella). Minimum inhibitory concentration (MIC) values of the rGO/Ag NCs ranged from 1.9 to 125 µg/mL. The best inhibitory activity was obtained for rGO/Ag12%, mainly against Candida spp. and Epidermophyton floccosum. In the presence of sorbitol, MIC values of rGO/Ag NCs were higher (ranging from 15.6 to 250 µg/mL), indicating the action mechanism on the cell wall. Both yeast and dermatophytes clinical isolates were inhibited at a minimum of 6 and 24 h, respectively, but after 2 and 12 h, they had initial antifungal interference. All hybrid formulations of rGO/Ag NCs were not toxic for G. mellonella. This study provides insights into an alternative therapeutic strategy for controlling dermatomycoses.


Assuntos
Arthrodermataceae , Dermatomicoses , Nanocompostos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candida , Prata/farmacologia , Trichophyton , Dermatomicoses/tratamento farmacológico
6.
Evol Lett ; 7(1): 58-66, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37065437

RESUMO

Virulence is expected to be linked to parasite fitness via transmission. However, it is not clear whether this relationship is genetically determined, nor if it differs when transmission occurs continuously during, or only at the end of, the infection period. Here, we used inbred lines of the macroparasitic spider mite Tetranychus urticae to disentangle genetic vs. nongenetic correlations among traits, while varying parasite density and opportunities for transmission. A positive genetic correlation between virulence and the number of transmitting stages produced was found under continuous transmission. However, if transmission occurred only at the end of the infection period, this genetic correlation disappeared. Instead, we observed a negative relationship between virulence and the number of transmitting stages, driven by density dependence. Thus, within-host density dependence caused by reduced opportunities for transmission may hamper selection for higher virulence, providing a novel explanation as to why limited host availability leads to lower virulence.

7.
Clin Neurol Neurosurg ; 221: 107408, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35985096

RESUMO

OBJECTIVE: To determine the postdrome's prevalence and characterize its clinical manifestations, to assess the impact of these symptoms on the patients' activities of daily living, work activity and quality of life and to assess the factors that influence the postdrome's frequency and duration. METHODS: One hundred patients with migraine were screened about the occurrence of postdrome and its characteristics using a self-fulfilled questionnaire. RESULTS: Ninety-four patients reported between 1 and 23 postdrome symptoms (mean 8.0 ± 4.3 symptoms). The most reported symptoms were fatigue, difficulty with concentration and head discomfort. The frequency of the headache did not influence the frequency of the postdrome but correlated with the number of postdrome symptoms and the postdrome's duration. 82.8 % of patients reported an impact in quality of life. Most of the patients (77.4 %) did not report a difference in the duration of the postdrome when taking medication to relieve the migraine headache. Discomfort felt did not differ between patients prescribed with different abortive medication. Patients prescribed with NSAID reported more postdrome symptoms while patients prescribed with triptans identified a bigger impact in quality of life. CONCLUSION: Postdrome symptoms are frequent, diverse and cause significant disability. Abortive treatment directed to pain control is not efficient in postdrome symptoms. Understanding this phase may enhance our understanding of migraine and lead to better therapeutic approaches.


Assuntos
Transtornos de Enxaqueca , Qualidade de Vida , Atividades Cotidianas , Anti-Inflamatórios não Esteroides/uso terapêutico , Humanos , Transtornos de Enxaqueca/diagnóstico , Transtornos de Enxaqueca/tratamento farmacológico , Transtornos de Enxaqueca/epidemiologia , Triptaminas/uso terapêutico
9.
Plant Environ Interact ; 3(4): 170-178, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37283609

RESUMO

The effects of metals on plants and herbivores, as well as the interaction among the latter, are well documented. However, the effects of simultaneous herbivory and metal accumulation remain poorly studied. Here, we shed light on this topic by infesting cadmium-accumulating tomato plants (Solanum lycopersicum), either exposed to cadmium or not, with herbivorous spider mites, Tetranychus urticae or T. evansi during 14 days. Whereas on plants without cadmium T. evansi had higher growth rate than T. urticae, on plants with cadmium both mite species had similar growth rates, which were lower than on plants without metal. Plants were affected by both cadmium toxicity and by herbivory, as shown by leaf reflectance, but not on the same wavelengths. Moreover, changes in leaf reflectance on the wavelength affected by herbivores were similar on plants with and without cadmium, and vice versa. Long-term effects of cadmium and herbivory did not affect H2O2 concentrations in the plant. Finally, plants infested with spider mites did not accumulate more cadmium, suggesting that metal accumulation is not induced by herbivory. We thus conclude that cadmium accumulation affects two congeneric herbivore species differently and that the effects of herbivory and cadmium toxicity on plants may be disentangled, via leaf reflectance, even during simultaneous exposure.

10.
Motriz (Online) ; 28: e10220005821, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1394480

RESUMO

Abstract Aim: This study aimed to analyze the difference between tactical, technical, and physical variables in selected and unselected top players of the 2018 FIFA World Cup. Methods: A sample data of 1049 soccer players were collected by the multiple-camera computerised tracking system. Subsequently, data were analyzed and divided into two groups: selected (man of the match and top 10 players of the World Cup) and unselected players (other players). Twenty-six performance variables were used to assess tactical (passing), technical (goals, assist, shots, and fouls), and physical variables (height, distance covered, distance with and without the ball, number of sprints, maximal speed, and intensities zone 1 [low] to 5 [high]). Results: The selected players had more tactical (performed and completed more long, middle, and short pass), technical (goal for, assist, shots, shots on goal, fouls committed on them), and physical variables (covered more distance and distance with the ball, more sprints, greater speed and distance in low intensity [zone 1]). However, they were shorter in height and covered less distance in moderate intensity [zones 2 and 3] when compared to unselected players (p < 0.05). Conclusion: This study suggests that the selected players have more tactical, technical, and physical variables than the unselected players. Our findings could be used as a trustworthy tool (performance variables) to characterize the top players of the World Cup.


Assuntos
Humanos , Aptidão , Futebol , Avaliação de Desempenho Profissional , Atletas , Análise de Variância , Análise de Dados
11.
World Neurosurg ; 155: e548-e563, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34481106

RESUMO

OBJECTIVE: There is a paucity of clinical evidence that guides perioperative glycemia management in patients undergoing craniotomy for brain tumor resection. The purpose of this study was to better understand global perceptions and practices related to glycemia management in these patients. METHODS: Neuroanesthesiologists throughout North America, South America, Europe, and Asia filled out a brief online questionnaire related to their perceptions and practices regarding glycemia management in patients undergoing craniotomy for brain tumor resection. RESULTS: Over 4 weeks, 435 participants practicing in 34 countries across 6 continents participated in this survey. Although responders in North America were found to perceive a higher risk hyperglycemia compared with those practicing in European (P = 0.024) and South Asian (P = 0.007) countries, responders practicing in South Asian countries (P = 0.030), Middle Eastern countries (P = 0.029), and South American (P = 0.005) countries were more likely than those from North America to remeasure glucose after an initial normal glucose measurement at incision. Responders from North America reported that a higher blood glucose threshold was necessary for them to delay or cancel the surgery compared with responders in Slavic (P < 0.001), European (P = 0.002), South American (P = 0.002), and Asian and Pacific (P < 0.001) countries. Responders from North America were more likely to report that they would delay or cancel the surgery because of a higher blood glucose threshold. CONCLUSIONS: Our survey results suggest that perceptions and practices related to blood glucose management in patients undergoing brain tumor resection are variable. This study highlights the need for stronger clinical evidence and guidelines to help guide decisions for when and how to manage blood glucose derangements in these patients.


Assuntos
Anestesiologistas/psicologia , Neoplasias Encefálicas/cirurgia , Craniotomia , Índice Glicêmico , Assistência Perioperatória/métodos , Inquéritos e Questionários , Atitude do Pessoal de Saúde , Neoplasias Encefálicas/sangue , Gerenciamento Clínico , Feminino , Saúde Global , Índice Glicêmico/fisiologia , Humanos , Internacionalidade , Masculino
12.
An Acad Bras Cienc ; 93(4): e20200096, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34495200

RESUMO

Biochar has been used to reuse the agro-industrial wastes and improve soil quality. Several studies have been carried out to show the impact of biochar on physical and chemical soil attributes. However, there are still gaps regarding the effects on as microbial biomass and enzymatic activities that are important to determine sensitive indicators to evaluate changes in management practices. The objective of this study was to assess the effect of two biochars on the chemical, microbial biomass carbon, and the enzymatic activities in an Entisol cultivated with bean. We evaluate two types of coffee biochar: ground and husks, four doses (4, 8, 12, and 16 Mg ha-1) and control. All treatments received organic fertilization with cow manure. Husks biochar increase the soil pH, Ca, and K, also contributing to the reduction of toxic aluminum contents and raising the concentrations of P labile. The treatments that received ground biochar showed higher soil organic carbon, microbial biomass, ß-glucosidase, and fluorescein diacetate. Biochar produced from coffee residues increased sandy soil quality. We showed the first report on the beneficial impact of coffee biochar on enzymatic and microbiological quality of sandy soil cultivated with the bean.


Assuntos
Carbono , Solo , Biomassa , Carbono/análise , Carvão Vegetal , Café , Areia
13.
J Neurosurg Spine ; 35(6): 834-843, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34416733

RESUMO

OBJECTIVE: High-grade spinal glioma (HGSG) is a rare but aggressive tumor that occurs in both adults and children. Histone H3 K27M mutation correlates with poor prognosis in children with diffuse midline glioma. However, the role of H3 K27M mutation in the prognosis of adults with HGSG remains unclear owing to the rarity of this mutation, conflicting reports, and the absence of multicenter studies on this topic. METHODS: The authors studied a cohort of 30 adult patients with diffuse HGSG who underwent histological confirmation of diagnosis, surgical intervention, and treatment between January 2000 and July 2020 at six tertiary academic centers. The primary outcome was the effect of H3 K27M mutation status on progression-free survival (PFS) and overall survival (OS). RESULTS: Thirty patients (18 males and 12 females) with a median (range) age of 50.5 (19-76) years were included in the analysis. Eighteen patients had H3 K27M mutation-positive tumors, and 12 had H3 K27M mutation-negative tumors. The median (interquartile range) PFS was 3 (10) months, and the median (interquartile range) OS was 9 (23) months. The factors associated with increased survival were treatment with concurrent chemotherapy/radiation (p = 0.006 for PFS, and p ≤ 0.001 for OS) and American Spinal Injury Association grade C or better at presentation (p = 0.043 for PFS, and p < 0.001 for OS). There were no significant differences in outcomes based on tumor location, extent of resection, sex, or H3 K27M mutation status. Analysis restricted to HGSG containing necrosis and/or microvascular proliferation (WHO grade IV histological features) revealed increased OS for patients with H3 K27M mutation-positive tumors (p = 0.017). CONCLUSIONS: Although H3 K27M mutant-positive HGSG was associated with poor outcomes in adult patients, the outcomes of patients with H3 K27M mutant-positive HGSG were somewhat more favorable compared with those of their H3 K27M mutant-negative HGSG counterparts. Further preclinical animal studies and larger clinical studies are needed to further understand the age-dependent effects of H3 K27M mutation.


Assuntos
Neoplasias Encefálicas , Glioma , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Feminino , Glioma/genética , Glioma/patologia , Glioma/terapia , Histonas/genética , Humanos , Masculino , Mutação/genética , Prognóstico
14.
J Neurooncol ; 153(1): 65-77, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33811630

RESUMO

BACKGROUND: En bloc spondylectomy is the gold standard for surgical resection of sacral chordomas (CHO), but the effect of extent of resection on recurrence and survival in patients with CHO of the cervical spine remains elusive. METHODS: MEDLINE, Embase, Scopus, and Cochrane were systematically reviewed. Patients with cervical CHO treated at three tertiary-care academic institutions were reviewed for inclusion. We performed an individual participant data meta-analysis to assess the overall survival (OS) and progression free survival (PFS) after en bloc-gross total resection (GTR) and intralesional-GTR compared to subtotal resection (STR). We then performed an intention-to-treat analysis including all patients with attempted en bloc resection in the en bloc group, regardless of the surgical margins. RESULTS: There was a total of 13 series including 161 patients with cervical CHO, including our current series of 22 patients. GTR (en bloc-GTR + intralesional-GTR) was associated with a significant decrease in the risk of local progression (pooled hazard ratio (PHR) = 0.22; 95% CI 0.08-0.59; p = 0.003) and risk of death (PHR 0.31; 95%; CI 0.12-0.83; p = 0.020). A meta-regression analyses determined that intralesional-GTR improved PFS (PHR 0.35; 95% CI 0.16-0.76; p = 0.009) as well as OS (PHR 0.25; 95% CI 0.08-0.79; p = 0.019) when compared to STR. En bloc-GTR was associated with a significant reduction in the risk of local progression (PHR 0.06; 95% CI 0.01-0.77; p = 0.030), but not a decreased OS (PHR 0.50; 95% CI 0.19-1.27; p = 0.145). Our intention-to-treat analyses revealed a near significant improvement in OS for the en bloc group (PHR: 0.15; 95% CI 0.02-1.22; p = 0.054), and nearly identical improvement in PFS. Radiation data was not available for the studies included in the meta-analysis. CONCLUSION: This is the first and only meta-analysis of patients with cervical CHO. We found that both en bloc-GTR and intralesional-GTR resulted in improved local tumor control when compared to STR.


Assuntos
Cordoma , Vértebras Cervicais/cirurgia , Cordoma/cirurgia , Humanos , Estudos Multicêntricos como Assunto , Estudos Retrospectivos , Neoplasias da Coluna Vertebral/cirurgia , Resultado do Tratamento
15.
Neurosurg Clin N Am ; 32(1): 1-8, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33223018

RESUMO

The clinical presentation of glioblastomas is varied, and definitive diagnosis requires pathologic examination and study of the tissue. Management of glioblastomas includes surgery and adjuvant chemotherapy and radiotherapy, with surgery playing an important role in the prognosis of these patients. Awake craniotomy plays a crucial role in tumors in or adjacent to eloquent areas, allowing surgeons to maximize resection, while minimizing iatrogenic deficits. However, the prognosis remains dismal. This article presents the perioperative management of patients with glioblastoma including tools and surgical adjuncts to maximize extent of resection and minimize poor outcomes.


Assuntos
Neoplasias Encefálicas/diagnóstico , Glioblastoma/diagnóstico , Glioblastoma/cirurgia , Procedimentos Neurocirúrgicos/métodos , Assistência Perioperatória/métodos , Humanos , Monitorização Intraoperatória , Período Perioperatório , Resultado do Tratamento
16.
Folia Morphol (Warsz) ; 80(4): 972-979, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33169355

RESUMO

BACKGROUND: Bone remodelling represents the most remarkable bone response to mechanical stress and mineral homeostasis. It is the consequence of complex highly orchestrated and tightly regulated cellular processes taking place in a specialised entity - the bone remodelling compartment (BRC). MATERIALS AND METHODS: Cementum is an understudied tissue that requires more research to understand its biology, pathology, and potential for regeneration. Although analogue to bone in structure and composition distinct structural and functional differences were ascribed to each of these mineralised tissues. The precise role of cementocytes in cementum turnover is unclear but they may work the same way as osteocytes in bone remodelling, regulating the full process. RESULTS: Although cementum is not liable to regular physiological remodelling as bone is, pathological cases triggered by orthodontic forces or large periapical periodontitis, those lesions can acutely induce cementum remodelling. Nevertheless, the cellular mechanisms behind this particular remodelling process are yet to be identified, as its eventual involvement of specialised anatomic structures as the BRC. CONCLUSIONS: Hypothesizing that similar cellular mechanisms underlie bone and cementum remodelling, the present work shows, for the first time, the histological evidence of a specialized remodelling compartment in dental hard tissues.


Assuntos
Cemento Dentário , Osteócitos
17.
World Neurosurg ; 146: 64-74, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33229311

RESUMO

The study of brain connectomics has led to a rapid evolution in the understanding of human brain function. Traditional localizationist theories are being replaced by more accurate network, or hodologic, approaches that model brain function as widespread processes dependent on cortical and subcortical structures, as well as the white matter tracts (WMTs) that link these areas. Recent surgical literature suggests that WMTs may be more critical to preserve than cortical structures because of the comparably lower capacity of recovery of the former when damaged. Given the relevance of eloquent WMTs to neurologic function and thus quality of life, neurosurgical interventions must be tailored to maximize their preservation. Direct electric stimulation remains a vital tool for identification and avoidance of these critical tracts. Neurosurgeons therefore require proper understanding of the anatomy and function of WMTs, as well as the reported contemporary tasks used during intraoperative stimulation. We review the relevant tracts involved in language, visuospatial, and motor networks and the updated direct electric stimulation-based mapping tasks that aid in their preservation. The dominant-hemisphere language WMTs have been mapped using picture naming, semantic association, word repetition, reading, and writing tasks. For monitoring of vision and spatial functions, the modified picture naming and line bisection tasks, as well as the recording of visual evoked potentials, have been used. Repetitive movements and monitoring of motor evoked potentials and involuntary movements have been applied for preservation of the motor networks.


Assuntos
Encéfalo/cirurgia , Estimulação Elétrica/métodos , Monitorização Neurofisiológica Intraoperatória/métodos , Vias Neurais , Substância Branca , Mapeamento Encefálico/métodos , Humanos , Procedimentos Neurocirúrgicos
18.
Ecol Evol ; 10(15): 8405-8415, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32788989

RESUMO

Few studies have tested how plant quality and the presence of competitors interact in determining how herbivores choose between different leaves within a plant. We investigated this in two herbivorous spider mites sharing tomato plants: Tetranychus urticae, which generally induces plant defenses, and Tetranychus evansi, which suppresses them, creating asymmetrical effects on coinfesting competitors. On uninfested plants, both herbivore species preferred young leaves, coinciding with increased mite performance. On plants with heterospecifics, the mites did not prefer leaves on which they had a better performance. In particular, T. urticae avoided leaves infested with T. evansi, which is in agreement with T. urticae being outcompeted by T. evansi. In contrast, T. evansi did not avoid leaves with the other species, but distributed itself evenly over plants infested with heterospecifics. We hypothesize that this behavior of T. evansi may prevent further spread of T. urticae over the shared plant. Our results indicate that leaf age determines within-plant distribution of herbivores only in absence of competitors. Moreover, they show that this distribution depends on the order of arrival of competitors and on their effects on each other, with herbivores showing differences in behavior within the plant as a possible response to the outcome of those interactions.

19.
Ecol Evol ; 10(14): 7291-7305, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32760529

RESUMO

Laboratory studies are often criticized for not being representative of processes occurring in natural populations. One reason for this is the fact that laboratory populations generally do not capture enough of the genetic variation of natural populations. This can be mitigated by mixing the genetic background of several field populations when creating laboratory populations. From these outbred populations, it is possible to generate inbred lines, thereby freezing and partitioning part of their variability, allowing each genotype to be characterized independently. Many studies addressing adaptation of organisms to their environment, such as those involving quantitative genetics or experimental evolution, rely on inbred or outbred populations, but the methodology underlying the generation of such biological resources is usually not explicitly documented. Here, we developed different procedures to circumvent common pitfalls of laboratory studies, and illustrate their application using two haplodiploid species, the spider mites Tetranychus urticae and Tetranychus evansi. First, we present a method that increases the chance of capturing high amounts of variability when creating outbred populations, by performing controlled crosses between individuals from different field-collected populations. Second, we depict the creation of inbred lines derived from such outbred populations, by performing several generations of sib-mating. Third, we outline an experimental evolution protocol that allows the maintenance of a constant population size at the beginning of each generation, thereby preventing bottlenecks and diminishing extinction risks. Finally, we discuss the advantages of these procedures and emphasize that sharing such biological resources and combining them with available genetic tools will allow consistent and comparable studies that greatly contribute to our understanding of ecological and evolutionary processes.

20.
ACS Appl Mater Interfaces ; 12(15): 17745-17751, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32250100

RESUMO

Monitoring carbon dioxide (CO2) levels is extremely important in a wide range of applications. Although metal oxide-based chemoresistive sensors have emerged as a promising approach for CO2 detection, the development of efficient CO2 sensors at low temperature remains a challenge. Herein, we report a low-temperature hollow nanostructured CeO2-based sensor for CO2 detection. We monitor the changes in the electrical resistance after CO2 pulses in a relative humidity of 70% and show the high performance of the sensor at 100 °C. The yolk-shell nanospheres have not only 2 times higher sensitivity but also significantly increased stability and reversibility, faster response times, and greater CO2 adsorption capacity than commercial ceria nanoparticles. The improvements in the CO2 sensing performance are attributed to hollow and porous structure of the yolk-shell nanoparticles, allowing for enhanced gas diffusion and high specific surface area. We present an easy strategy to enhance the electrical and sensing properties of metal oxides at a low operating temperature that is desirable for practical applications of CO2 sensors.

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