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1.
Int Braz J Urol ; 50(4): 489-499, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38701184

RESUMO

BACKGROUND: Robotic-assisted radical cystectomy (RARC) with intracorporeal urinary diversion (ICUD) is associated with significant morbidity and mortality. We present an alternative technique that preserves the complete mesenteric vascularization during the isolation of the intestinal segment used in ICUD, including distal vessels. This approach aims to minimize the risk of ischemia in both the ileal anastomosis and the isolated loop at the diversion site. METHODS: This cohort study included 31 patients, both male and female, who underwent RARC with ICUD from February 2018 to November 2023, performed by a single surgeon. Intraoperative and postoperative complications data were retrieved for analysis, employing our proposed mesentery-sparing technique in all cases. The primary endpoint was the incidence of intraoperative and postoperative complications directly attributable to the mesentery-sparing approach in ICUD. Secondary endpoints included other postoperative variables not directly related to mesentery preservation, such as the incidence of postoperative ileus requiring parenteral nutrition and the duration of hospitalization. RESULTS: None of the patients experienced intraoperative or postoperative complications directly related to mesentery-sparing, such as intestinal fistulae or internal hernias. The median duration of hospitalization was 6 days, and postoperative ileus necessitating total parenteral nutrition occurred in 19% of the patients. Minor complications (Clavien-Dindo grades I-II) accounted for 27.6% of the cases and major complications (grades III-V) accounted for 20.6%. CONCLUSION: The mesentery-sparing technique outlined herein offers an alternative method for preserving the vascularization of intestinal segments and reducing the risk of intestinal complications in ICUD during RARC.


Assuntos
Cistectomia , Mesentério , Complicações Pós-Operatórias , Procedimentos Cirúrgicos Robóticos , Derivação Urinária , Humanos , Cistectomia/métodos , Feminino , Masculino , Procedimentos Cirúrgicos Robóticos/métodos , Derivação Urinária/métodos , Pessoa de Meia-Idade , Idoso , Complicações Pós-Operatórias/prevenção & controle , Mesentério/cirurgia , Neoplasias da Bexiga Urinária/cirurgia , Tratamentos com Preservação do Órgão/métodos , Resultado do Tratamento , Complicações Intraoperatórias/prevenção & controle , Estudos Retrospectivos , Reprodutibilidade dos Testes , Estudos de Coortes
2.
BMC Genomics ; 24(1): 677, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37950193

RESUMO

BACKGROUND: Macrobrachium amazonicum is a freshwater prawn widely distributed in South America that is undergoing speciation, so the denomination "M. amazonicum complex" is used for it. The mitochondrial cytochrome c oxidase subunit I (COI) gene has been used to elucidate this speciation, but heteroplasmies and pseudogenes have been recorded, making separation difficult. Obtaining genes from cDNA (RNA) rather than genomic DNA is an effective tool to mitigate those two types of occurrences. The aim of this study was to assemble in silico the mitochondrial DNA (mtDNA) of the Amazonian coastal population of M. amazonicum inhabiting the state of Pará. RESULTS: Sequences were obtained from the prawn's transcriptome using the de novo approach. Six libraries of cDNA from the androgen gland, hepatopancreas, and muscle tissue were used. The mtDNA of M. amazonicum was 14,960 bp in length. It contained 13 protein-coding genes, 21 complete transfer RNAs, and the 12S and 16S subunits of ribosomal RNA. All regions were found on the light strand except tRNAGln, which was on the heavy strand. The control region (D-loop) was not recovered, making for a gap of 793 bp. The cladogram showed the formation of the well-defined Macrobrachium clade, with high support value in the established branches (91-100). The three-dimensional spatial conformation of the mtDNA-encoded proteins showed that most of them were mainly composed of major α-helices that typically shows in those proteins inserted in the membrane (mitochondrial). CONCLUSIONS: It was possible to assemble a large part of the mitochondrial genome of M. amazonicum in silico using data from other genomes deposited in GenBank and to validate it through the similarities between its COI and 16S genes and those from animals of the same region deposited in GenBank. Depositing the M. amazonicum mtDNA sequences in GenBank may help solve the taxonomic problems recorded for the species, in addition to providing complete sequences of candidate coding genes for use as biomarkers in ecological studies.


Assuntos
Genoma Mitocondrial , Palaemonidae , Animais , DNA Mitocondrial/genética , Palaemonidae/genética , DNA Complementar , Transcriptoma , RNA de Transferência/genética , Filogenia
3.
Front Neural Circuits ; 16: 747910, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36034337

RESUMO

Epilepsy is one of the most common neurological disorders worldwide. Recent findings suggest that the brain is a complex system composed of a network of neurons, and seizure is considered an emergent property resulting from its interactions. Based on this perspective, network physiology has emerged as a promising approach to explore how brain areas coordinate, synchronize and integrate their dynamics, both under perfect health and critical illness conditions. Therefore, the objective of this paper is to present an application of (Dynamic) Bayesian Networks (DBN) to model Local Field Potentials (LFP) data on rats induced to epileptic seizures based on the number of arcs found using threshold analytics. Results showed that DBN analysis captured the dynamic nature of brain connectivity across ictogenesis and a significant correlation with neurobiology derived from pioneering studies employing techniques of pharmacological manipulation, lesion, and modern optogenetics. The arcs evaluated under the proposed approach achieved consistent results based on previous literature, in addition to demonstrating robustness regarding functional connectivity analysis. Moreover, it provided fascinating and novel insights, such as discontinuity between forelimb clonus and generalized tonic-clonic seizure (GTCS) dynamics. Thus, DBN coupled with threshold analytics may be an excellent tool for investigating brain circuitry and their dynamical interplay, both in homeostasis and dysfunction conditions.


Assuntos
Epilepsia , Animais , Ratos , Teorema de Bayes , Encéfalo , Convulsões
4.
Insects ; 13(2)2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35206754

RESUMO

Interactive movements of bees facilitate the division and organization of collective tasks, notably when they need to face internal or external environmental challenges. Here, we present a Bayesian and computational approach to track the movement of several honey bee, Apis mellifera, workers at colony level. We applied algorithms that combined tracking and Kernel Density Estimation (KDE), allowing measurements of entropy and Probability Distribution Function (PDF) of the motion of tracked organisms. We placed approximately 200 recently emerged and labeled bees inside an experimental colony, which consists of a mated queen, approximately 1000 bees, and a naturally occurring beehive background. Before release, labeled bees were fed for one hour with uncontaminated diets or diets containing a commercial mixture of synthetic fungicides (thiophanate-methyl and chlorothalonil). The colonies were filmed (12 min) at the 1st hour, 5th and 10th days after the bees' release. Our results revealed that the algorithm tracked the labeled bees with great accuracy. Pesticide-contaminated colonies showed anticipated collective activities in peripheral hive areas, far from the brood area, and exhibited reduced swarm entropy and energy values when compared to uncontaminated colonies. Collectively, our approach opens novel possibilities to quantify and predict potential alterations mediated by pollutants (e.g., pesticides) at the bee colony-level.

5.
Entropy (Basel) ; 23(10)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34682064

RESUMO

Entropy is a concept that emerged in the 19th century. It used to be associated with heat harnessed by a thermal machine to perform work during the Industrial Revolution. However, there was an unprecedented scientific revolution in the 20th century due to one of its most essential innovations, i.e., the information theory, which also encompasses the concept of entropy. Therefore, the following question is naturally raised: "what is the difference, if any, between concepts of entropy in each field of knowledge?" There are misconceptions, as there have been multiple attempts to conciliate the entropy of thermodynamics with that of information theory. Entropy is most commonly defined as "disorder", although it is not a good analogy since "order" is a subjective human concept, and "disorder" cannot always be obtained from entropy. Therefore, this paper presents a historical background on the evolution of the term "entropy", and provides mathematical evidence and logical arguments regarding its interconnection in various scientific areas, with the objective of providing a theoretical review and reference material for a broad audience.

6.
Epilepsy Behav ; 122: 108166, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34343958

RESUMO

Electrical Stimulation (ES) of the nervous system is a promising alternative to treat refractory epilepsy. Recent developments in the area have led to a novel method involving a non-standard form of electrical stimulation with randomized inter-pulse intervals called non-periodic stimulation (NPS). Although it is an interesting approach, there is limited statistical proof to confirm its effectiveness. Therefore this brief communication presents a survival analysis of a pre-clinical trial to assess the significance of NPS therapy. The experiment comprised four groups of rats that have been compared: two with and two without NPS treatment. ES was applied bilaterally to the amygdala in animals subjected to the pentylenetetrazole continuous infusion (10 mg/ml/min) model, myoclonic or tonic-clonic generalized seizures were triggered. The Kaplan-Meier estimator was used to develop survival functions and the Logrank test was carried out to check the differences among groups. The first comparison was made between two groups of rats that developed generalized tonic-clonic seizures (GTC groups), those who received NPS treatment took longer to develop epileptic seizures. The logrank test proved statistical difference due to reaching a p-value of 7%. The second comparison was performed between two groups of rats that developed myoclonic seizures (MYO groups), and once again better survival probabilities were observed for the NPS group. The Logrank test revealed a p-value of 0.5% thereof. Thus, a survival analysis of NPS treatment proved effectiveness against seizures by promoting an anticonvulsant effect. By comparing the groups selected for this study, it was found that the NPS treatment yielded better results, mainly against myoclonic seizures.


Assuntos
Epilepsia Resistente a Medicamentos , Pentilenotetrazol , Animais , Anticonvulsivantes/uso terapêutico , Epilepsia Resistente a Medicamentos/tratamento farmacológico , Pentilenotetrazol/toxicidade , Ratos , Convulsões/tratamento farmacológico , Análise de Sobrevida
7.
J Robot Surg ; 15(6): 829-839, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33426578

RESUMO

Radical prostatectomy is a commonly adopted treatment for localized/locally advanced prostate cancer in men with a life expectancy of ten years or more. Robotic-assisted radical prostatectomy (RARP) is comparable to open radical prostatectomy on cancer control and complication rates; however, new evidence suggests that RARP may have better functional outcomes, especially with respect to urinary incontinence and erectile dysfunction. Some of the surgical steps of RARP are not adequately described in published literature and, as such, may have an impact on the final outcomes of the procedure. We organized a Brazilian experts' panel to evaluate best practices in RARP. The confection of the recommendations broadly involved: selection of the experts; establishment of working groups; systematic review of the literature and elaboration of a questionnaire; and construction of the final text with the approval of all participants. The participants reviewed the publications in English from December 2019 to February 2020. A one-round Delphi technique was employed in 188 questions. Five reviewers worked on the final recommendations using consensual and non-consensual questions. We found 59.9% of questions with greater than 70% agreement that were considered consensual. Non-consensual questions were reported according to the responses. The recommendations were based on evidence-based literature and individual perceptions adapted to the Brazilian reality, although some issues remain controversial. We believe that these recommendations may help urologists involved in RARP and hope that future discussions on this surgical procedure may evolve over the ensuing years.


Assuntos
Neoplasias da Próstata , Procedimentos Cirúrgicos Robóticos , Consenso , Humanos , Masculino , Guias de Prática Clínica como Assunto , Próstata , Prostatectomia , Neoplasias da Próstata/cirurgia , Procedimentos Cirúrgicos Robóticos/métodos , Resultado do Tratamento
8.
Urol Case Rep ; 34: 101441, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33102127

RESUMO

Penile cancer has a high incidence in developing countries. The gold standard treatment is penectomy, however, due to its mutilating nature, organ-preserving techniques such as Mohs' micrography have been developed. This is indicated in small and low-grade invasive tumors, as well as in situ neoplasia. In this regard, we report the case of a young patient with a neoplastic injury in the glans, who had undergone Mohs' micrographic surgery and who achieved satisfactory aesthetic, functional, and oncological results. Despite the recurrence, he had a new surgery by the same method with good outcomes.

9.
Int. braz. j. urol ; 45(4): 671-678, July-Aug. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1019884

RESUMO

ABSTRACT Introduction Penile cancer (PC) occurs less frequently in Europe and in the United States than in South America and parts of Africa. Lymph node (LN) involvement is the most important prognostic factor, and inguinal LN (ILN) dissection can be curative; however, ILN dissection has high morbidity. A nomogram was previously developed based on clinicopathological features of PC to predict ILN metastases. Our objective was to conduct an external validation of the previously developed nomogram based on our population. Materials and methods We included men with cN0 ILNs who underwent ILN dissection for penile carcinoma between 2000 and 2014. We performed external validation of the nomogram considering three different external validation methods: k-fold, leave-one-out, and bootstrap. We also analyzed prognostic variables. Performance was quantified in terms of calibration and discrimination (receiver operator characteristic curve). A logistic regression model for positive ILNs was developed based on clinicopathological features of PC. Results We analyzed 65 men who underwent ILN dissection (cN0). The mean age was 56.8 years. Of 65 men, 24 (36.9%) presented with positive LNs. A median 21 ILNs were removed. Considering the three different methods used, we concluded that the previously developed nomogram was not suitable for our sample. Conclusions In our study, the previously developed nomogram that was applied to our population had low accuracy and low precision for correctly identifying patients with PC who have positive ILNs.


Assuntos
Humanos , Masculino , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Penianas/patologia , Carcinoma/patologia , Nomogramas , Canal Inguinal/patologia , Linfonodos/patologia , Metástase Linfática/diagnóstico , Valores de Referência , Modelos Logísticos , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores de Risco , Curva ROC , Proteína Supressora de Tumor p53/análise , Estatísticas não Paramétricas , Gradação de Tumores , Excisão de Linfonodo , Pessoa de Meia-Idade , Estadiamento de Neoplasias
10.
Int Braz J Urol ; 45(4): 671-678, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31136111

RESUMO

INTRODUCTION: Penile cancer (PC) occurs less frequently in Europe and in the United States than in South America and parts of Africa. Lymph node (LN) involvement is the most important prognostic factor, and inguinal LN (ILN) dissection can be curative; however, ILN dissection has high morbidity. A nomogram was previously developed based on clinicopathological features of PC to predict ILN metastases. Our objective was to conduct an external validation of the previously developed nomogram based on our population. MATERIALS AND METHODS: We included men with cN0 ILNs who underwent ILN dissection for penile carcinoma between 2000 and 2014. We performed external validation of the nomogram considering three different external validation methods: k-fold, leave-oneout, and bootstrap. We also analyzed prognostic variables. Performance was quantified in terms of calibration and discrimination (receiver operator characteristic curve). A logistic regression model for positive ILNs was developed based on clinicopathological features of PC. RESULTS: We analyzed 65 men who underwent ILN dissection (cN0). The mean age was 56.8 years. Of 65 men, 24 (36.9%) presented with positive LNs. A median 21 ILNs were removed. Considering the three different methods used, we concluded that the previously developed nomogram was not suitable for our sample. CONCLUSIONS: In our study, the previously developed nomogram that was applied to our population had low accuracy and low precision for correctly identifying patients with PC who have positive ILNs.


Assuntos
Carcinoma/patologia , Canal Inguinal/patologia , Linfonodos/patologia , Metástase Linfática/diagnóstico , Nomogramas , Neoplasias Penianas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Modelos Logísticos , Excisão de Linfonodo , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Curva ROC , Valores de Referência , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores de Risco , Estatísticas não Paramétricas , Proteína Supressora de Tumor p53/análise
11.
Phys Ther Sport ; 36: 92-100, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30703643

RESUMO

OBJECTIVES: Analyze the effects of 3 gait retraining: forefoot landing (FFOOT), 10% step rate increase (SR10%) and forward trunk lean (FTL) on lower limb biomechanics and clinical measurements in patellofemoral pain (PFP) runners. DESIGN: Case series report. SETTINGS: Biomechanical laboratory and treadmill running. PARTICIPANTS: Eighteen recreational PFP runners randomized in 3 groups. MAIN OUTCOME MEASURES: Lower limb kinematics and muscle activation were assessed at baseline and 2-week post-training. Pain intensity and function limitation, measured by AKPS (Anterior Knee Pain Scale) and LEFS (Lower Extremity Functional Scale) assessed at baseline, post-training and 6-month follow-up. Repeated measures analysis of variance was used to compare the effects of gait retraining. RESULTS: FFOOT and FTL increased the AKPS score at post-training(P = .001; P = .008) and 6-month follow-up(P < .001; P < .001). SR10% increased the AKPS score from baseline to 6-month follow-up(P = .006). Pain and LEFS score were improved after gait retraining regardless group. FFOOT presented greater gastrocnemius(P = .037) and rectus femoris pre-activation(P = .006) at post-retraining session. Gait retraining reduced the muscle activity during stance phase and increased during the late-swing regardless group. CONCLUSION: The three techniques presented clinical benefits, improvement of pain symptoms and functional scores, was not accompanied with significant biomechanics differences that could entirely explain this clinical improvement after the intervention.


Assuntos
Terapia por Exercício/métodos , Marcha/fisiologia , Síndrome da Dor Patelofemoral/reabilitação , Adulto , Fenômenos Biomecânicos/fisiologia , Feminino , Humanos , Extremidade Inferior/fisiologia , Masculino , Medição da Dor , Síndrome da Dor Patelofemoral/fisiopatologia , Corrida/fisiologia
12.
Rio de Janeiro; Eldorado; 2019. 216 p.
Monografia em Português | LILACS | ID: biblio-1103219

RESUMO

O livro é o resultado do conhecimento e expertise de uma equipe multidisciplinar do IFF/Fiocruz. Nele, o leitor encontrará os elementos necessários para refletir sobre o cuidado de crianças e adolescentes internados com dificuldades de voltar para casa, seja por dependência tecnológica, por complicações próprias das suas condições crônicas ou por falta de recursos para obter os cuidados e a assistência domiciliar que precisam para a desospitalização, além da atenção à doença.


Assuntos
Humanos , Criança , Criança , Saúde Pública , Doença Crônica , Assistência Domiciliar
13.
Artif Intell Med ; 90: 53-60, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30076067

RESUMO

Globally, the proportion of elderly individuals in the population has increased substantially in the last few decades. However, the risk factors that should be managed in advance to ensure a natural process of mental decline due to aging remain unknown. In this study, a dataset consisting of a Brazilian elderly sample was modelled using a Bayesian Network (BN) approach to uncover connections between cognitive performance measures and potential influence factors. Regarding its structure (a Directed Acyclic Graph), it was investigated the probabilistic dependence mechanism between two variables of medical interest: the suspected risk factor known as Metabolic Syndrome (MetS) and the indicator of mental decline referred to as Cognitive Impairment (CI). In this investigation, the concept known in the context of a BN as D-separation has been employed. Results of the conducted study revealed that the dependence between MetS and Cognitive Variables (CI and its direct determinants) in fact exists and depends on both Body Mass Index (BMI) and age.


Assuntos
Cognição , Disfunção Cognitiva/epidemiologia , Mineração de Dados/métodos , Síndrome Metabólica/epidemiologia , Fatores Etários , Idoso , Envelhecimento/psicologia , Teorema de Bayes , Índice de Massa Corporal , Brasil/epidemiologia , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/psicologia , Estudos Transversais , Bases de Dados Factuais , Feminino , Humanos , Masculino , Síndrome Metabólica/diagnóstico , Síndrome Metabólica/psicologia , Medição de Risco , Fatores de Risco
14.
Magn Reson Imaging ; 45: 1-6, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28893660

RESUMO

A four-channel Tic-Tac-Toe (TTT) transmit RF coil was designed and constructed for foot and ankle imaging at 7T MRI. Numerical simulations using an in-house developed FDTD package and experimental analyses using a homogenous phantom show an excellent agreement in terms of B1+ field distribution and s-parameters. Simulations performed on an anatomically detailed human lower leg model demonstrated an B1+ field distribution with a coefficient of variation (CV) of 23.9%/15.6%/28.8% and average B1+ of 0.33µT/0.56µT/0.43µT for 1W input power (i.e., 0.25W per channel) in the ankle/calcaneus/mid foot respectively. In-vivo B1+ mapping shows an average B1+ of 0.29µT over the entire foot/ankle. This newly developed RF coil also presents acceptable levels of average SAR (0.07W/kg for 10g per 1W of input power) and peak SAR (0.34W/kg for 10g per 1W of input power) over the whole lower leg. Preliminary in-vivo images in the foot/ankle were acquired using the T2-DESS MRI sequence without the use of a dedicated receive-only array.


Assuntos
Pé/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Imagens de Fantasmas , Tornozelo/anatomia & histologia , Tornozelo/diagnóstico por imagem , Desenho de Equipamento , Pé/diagnóstico por imagem , Humanos , Modelos Biológicos , Ondas de Rádio
15.
Artigo em Inglês | MEDLINE | ID: mdl-29164109

RESUMO

The knowledge of motion dynamics during running activity is crucial to enhance the development of rehabilitation techniques and injury prevention programs. Recent studies investigated the interaction between joints, using several analysis techniques, as cross-correlation, sensitivity analysis, among others. However, the direction of the joints pairing is still not understood. This paper proposes a study of the influence direction pattern in healthy runners by using kinematic data together with partial directed coherence, a frequency approach of Granger causality. The analysis was divided into three anatomical planes, sagittal, frontal, and transverse, and using data from ankle, knee, hip, and trunk segments. Results indicate a predominance of proximal to distal influence during running, reflecting a centralized anatomic source of movements. These findings highlight the necessity of managing proximal joints movements, in addition to motor control and core (trunk and hip) strengthening training to lumbar spine, knee, and ankle injuries prevention and rehabilitation.

16.
J Comput Neurosci ; 43(2): 159-171, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28791522

RESUMO

Directed information transfer measures are increasingly being employed in modeling neural system behavior due to their model-free approach, applicability to nonlinear and stochastic signals, and the potential to integrate repetitions of an experiment. Intracellular physiological recordings of graded synaptic potentials provide a number of additional challenges compared to spike signals due to non-stationary behaviour generated through extrinsic processes. We therefore propose a method to overcome this difficulty by using a preprocessing step based on Singular Spectrum Analysis (SSA) to remove nonlinear trends and discontinuities. We apply the method to intracellular recordings of synaptic responses of identified motor neurons evoked by stimulation of a proprioceptor that monitors limb position in leg of the desert locust. We then apply normalized delayed transfer entropy measures to neural responses evoked by displacements of the proprioceptor, the femoral chordotonal organ, that contains sensory neurones that monitor movements about the femoral-tibial joint. We then determine the consistency of responses within an individual recording of an identified motor neuron in a single animal, between repetitions of the same experiment in an identified motor neurons in the same animal and in repetitions of the same experiment from the same identified motor neuron in different animals. We found that delayed transfer entropy measures were consistent for a given identified neuron within and between animals and that they predict neural connectivity for the fast extensor tibiae motor neuron.


Assuntos
Entropia , Extremidades/fisiologia , Modelos Neurológicos , Neurônios Motores/fisiologia , Movimento/fisiologia , Potenciais de Ação/fisiologia , Algoritmos , Animais , Estimulação Elétrica , Feminino , Gafanhotos , Masculino , Distribuição Normal , Análise Espectral
17.
R Soc Open Sci ; 4(1): 160866, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28280585

RESUMO

Bees are key pollinators whose population numbers are declining, in part, owing to the effects of different stressors such as insecticides and fungicides. We have analysed the susceptibility of the Africanized honeybee, Apis mellifera, and the stingless bee, Partamona helleri, to commercial formulations of the insecticides deltamethrin and imidacloprid. The toxicity of fungicides based on thiophanate-methyl and chlorothalonil were investigated individually and in combination, and with the insecticides. Results showed that stingless bees were more susceptible to insecticides than honeybees. The commercial fungicides thiophanate-methyl or chlorothalonil caused low mortality, regardless of concentration; however, their combination was as toxic as imidacloprid to both species, and over 400-fold more toxic than deltamethrin for A. mellifera. There were highly synergistic effects on mortality caused by interactions in the mixture of imidacloprid and the fungicides thiophanate-methyl, chlorothalonil and the combined fungicide formulation in A. mellifera, and also to a lesser extent in P. helleri. By contrast, mixtures of the deltamethrin and the combined fungicide formulation induced high synergy in P. helleri, but had little effect on the mortality of A. mellifera. Differences in physiology and modes of action of agrochemicals are discussed as key factors underlying the differences in susceptibility to agrochemicals.

18.
J Comput Neurosci ; 38(2): 427-38, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25643986

RESUMO

Understanding the patterns of interconnections between neurons in complex networks is an enormous challenge using traditional physiological approaches. Here we combine the use of an information theoretic approach with intracellular recording to establish patterns of connections between layers of interneurons in a neural network responsible for mediating reflex movements of the hind limb of an insect. By analysing delayed mutual information of the synaptic and spiking responses of sensory neurons, spiking and nonspiking interneurons in response to movement of a joint receptor that monitors the position of the tibia relative to the femur, we are able to predict the patterns of interconnections between the layers of sensory neurons and interneurons in the network, with results matching closely those known from the literature. In addition, we use cross-correlation methods to establish the sign of those interconnections and show that they also show a high degree of similarity with those established for these networks over the last 30 years. The method proposed in this paper has great potential to elucidate functional connectivity at the neuronal level in many different neuronal networks.


Assuntos
Potenciais de Ação/fisiologia , Interneurônios/fisiologia , Modelos Neurológicos , Movimento/fisiologia , Redes Neurais de Computação , Células Receptoras Sensoriais/fisiologia , Animais , Membro Posterior/fisiologia , Insetos
19.
Man Ther ; 20(1): 79-83, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25081219

RESUMO

Foot misalignments, such as forefoot varus (FV), have been associated with musculoskeletal injuries in the proximal joints of the lower limb. Previous theories suggested that this association occurs because FV influences knee and hip kinematics during closed kinetic chain activities. However, research on the effects of FV in the kinematics of the lower limb is very scarce. Therefore, the purpose of this study was to compare the knee and hip kinematics between subjects with and without FV during a functional weight-bearing activity. Forty-six healthy adolescents were divided into two groups: group of subjects with FV (VG, n = 23) and group of subjects with aligned forefoot (CG, n = 23). A kinematic evaluation was conducted while the subjects performed a single-leg squat task. The variables of interest were hip internal rotation and adduction and knee abduction excursions at 15°, 30°, 45° and 60° of knee flexion. Between-group comparisons were performed with multivariate analysis of variance. Results showed that the VG presented greater hip internal rotation when compared with the CG across all evaluated knee flexion angles (P = 0.02-0.0001). No differences between groups were observed in hip adduction or knee abduction (P > 0.05). These results indicate that FV influences the transverse plane hip movement patterns during a functional weight-bearing activity. Considering that excessive hip internal rotation has been associated with knee injuries, these findings might contribute for a better understanding of the link between FV and injuries of the proximal joints of the lower limb.


Assuntos
Deformidades Congênitas do Pé/fisiopatologia , Articulação do Quadril/fisiopatologia , Articulação do Joelho/fisiopatologia , Adolescente , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Amplitude de Movimento Articular/fisiologia , Reprodutibilidade dos Testes , Rotação
20.
Man Ther ; 20(1): 189-93, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25261089

RESUMO

Patellofemoral pain (PFP) is a common lower extremity condition observed in sports clinics. Recently, it has been suggested that trunk motion could affect hip and knee biomechanics in the frontal plane. Thus, the purpose of the study was compare trunk kinematics, strength and muscle activation between people with PFP and healthy participants. In addition, the associations among trunk biomechanics, hip and knee kinematics were analysed. Thirty people with PFP and thirty pain-free individuals participated. The peak ipsilateral trunk lean, hip adduction, and knee abduction were evaluated with an electromagnetic tracking system, and the surface electromyographic signals of the iliocostalis and external oblique muscle were recorded during single-leg squats. Trunk extension and trunk flexion with rotation isometric strength and side bridge tests were quantified using a handheld dynamometer. Compared with the control group, the PFP group demonstrated increased ipsilateral trunk lean, hip adduction and knee abduction (p = 0.02-0.04) during single-leg squat accompanied with decreased trunk isometric strength (p = < 0.001-0.009). There was no between-group difference in trunk muscle activation. Only in the control group, ipsilateral trunk lean was significantly correlated with hip adduction (r = -0.66) and knee abduction (r = 0.49); also, the side bridge test correlated with knee abduction (r = -0.51). Differences in trunk, hip and knee biomechanics were found in people with PFP. No relationship among trunk, hip and knee biomechanics was found in the PFP group, suggesting that people with PFP show different movement patterns compared to the control group.


Assuntos
Articulação do Quadril/fisiopatologia , Articulação do Joelho/fisiopatologia , Síndrome da Dor Patelofemoral/fisiopatologia , Tórax/fisiopatologia , Adolescente , Adulto , Fenômenos Biomecânicos , Estudos de Casos e Controles , Eletromiografia , Feminino , Humanos , Masculino , Força Muscular/fisiologia , Rotação
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