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1.
Braz J Med Biol Res ; 56: e12484, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36946840

RESUMO

Borderline personality disorder (BPD) is a severe psychiatric condition that affects up to 2.7% of the population and is highly linked to functional impairment and suicide. Despite its severity, there is a lack of knowledge about its pathophysiology. Studies show genetic influence and childhood violence as factors that may contribute to the development of BPD; however, the involvement of neuroinflammation in BPD remains poorly investigated. This article aimed to explore the pathophysiology of BPD according to the levels of brain-derived neurotrophic factor (BDNF), inflammatory cytokines, and oxidative stress substances that exacerbate neuronal damage. Few articles have been published on this theme. They show that patients with BPD have a lower level of BDNF and a higher level of tumor necrosis factor (TNF)-α and interleukin (IL)-6 in peripheral blood, associated with increased plasma levels of oxidative stress markers, such as malondialdehyde and 8-hydroxy-2-deoxyguanosine. Therefore, more research on the topic is needed, mainly with a pre-clinical and clinical focus.


Assuntos
Transtorno da Personalidade Borderline , Humanos , Criança , Transtorno da Personalidade Borderline/epidemiologia , Transtorno da Personalidade Borderline/genética , Transtorno da Personalidade Borderline/psicologia , Fator Neurotrófico Derivado do Encéfalo/genética , Interleucina-6 , Fator de Necrose Tumoral alfa
2.
Braz. j. med. biol. res ; 56: e12484, 2023. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1420761

RESUMO

Borderline personality disorder (BPD) is a severe psychiatric condition that affects up to 2.7% of the population and is highly linked to functional impairment and suicide. Despite its severity, there is a lack of knowledge about its pathophysiology. Studies show genetic influence and childhood violence as factors that may contribute to the development of BPD; however, the involvement of neuroinflammation in BPD remains poorly investigated. This article aimed to explore the pathophysiology of BPD according to the levels of brain-derived neurotrophic factor (BDNF), inflammatory cytokines, and oxidative stress substances that exacerbate neuronal damage. Few articles have been published on this theme. They show that patients with BPD have a lower level of BDNF and a higher level of tumor necrosis factor (TNF)-α and interleukin (IL)-6 in peripheral blood, associated with increased plasma levels of oxidative stress markers, such as malondialdehyde and 8-hydroxy-2-deoxyguanosine. Therefore, more research on the topic is needed, mainly with a pre-clinical and clinical focus.

3.
Arq. bras. med. vet. zootec. (Online) ; 73(3): 589-597, May-June 2021. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1278368

RESUMO

This study aimed to evaluate the effectiveness of bridge plating of simple tibial fractures in dogs by minimally invasive plate osteosynthesis (MIPO). Medical and radiographic records of twenty-nine dogs with simple tibial fractures that underwent bridge fixation by MIPO were retrospectively evaluated. The clinical outcome was classified considering the presence of lameness at the end of the treatment. The tibial mechanical joint angles were measured and compared with the values described in the literature. Additionally, fragment apposition and implant disposition were evaluated. Based on the modified Radiographic Union Scale for Tibial fractures, the moment of clinical union was determined. Clinically, at the end of treatment, only one patient presented lameness at a trot. While there was no significant difference between the bone alignment in the frontal plane values and the values described in the literature (P>0.05), the caudal proximal tibial angle was significantly higher (P=0.001). The median fragment apposition was considered acceptable. The average bridge plate ratio, plate working length, and plate screw density were 0.8, 0.57, and 0.48, respectively. The median time to clinical union was 30 days. Bridge plating in simple tibial fractures resulted in fast healing and low complication rates.(AU)


Objetivou-se avaliar a efetividade da estabilização em ponte de fraturas tibiais simples em cães utilizando-se a técnica de osteossíntese minimamente invasiva com placa (MIPO). Registros médicos e radiográficos de 29 cães com fraturas simples de tíbia, fixadas em ponte por meio da MIPO, foram retrospectivamente avaliados. O resultado clínico foi classificado com base na deambulação ao final do tratamento. Os ângulos articulares mecânicos da tíbia foram aferidos e comparados aos valores descritos na literatura. Adicionalmente, foram avaliadas a aposição dos fragmentos e a disposição dos implantes. Por meio da escala modificada de união radiográfica para fraturas de tíbia, determinou-se o momento de união clínica. Clinicamente, ao final do tratamento, apenas um animal apresentou claudicação ao trote. Não houve diferença significativa entre o alinhamento ósseo no plano frontal quando comparado com dados da literatura (P>0,05), enquanto, no plano sagital, o ângulo mecânico caudal proximal da tíbia foi significativamente maior (P=0,001). A mediana para aposição dos fragmentos foi considerada aceitável. As médias para relação placa em ponte, comprimento de trabalho da placa e densidade de parafusos da placa foram, respectivamente, 0,8; 0,57 e 0,48. A mediana para união clínica foi de 30 dias. A estabilização em ponte de fraturas tibiais simples resultou em rápida consolidação óssea, com baixas taxas de complicação.(AU)


Assuntos
Animais , Cães , Fraturas da Tíbia/veterinária , Consolidação da Fratura , Fixação Interna de Fraturas/veterinária , Radiografia/veterinária
4.
Arq. bras. med. vet. zootec. (Online) ; 73(3): 647-652, May-June 2021. ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1278370

RESUMO

The treatment of fractures from the thoracic limb in giant anteaters is extremely challenging. Unfamiliar and peculiar anatomical characteristics, robust musculature and the imminent need for an early return to limb function highlight such challenges. The objective of this report was to describe the successful use of anatomical osteosynthesis with a robust locking compression plate in a humeral fracture of an adult giant anteater. The patient was rescued on the highway after being run over and presented for treatment at the Veterinary Teaching Hospital. Surgical stabilization was performed using a craniomedial approach to the humerus, using a customized broad 3.5mm locking compression plate. The patient presented early limb support at 24 hours postoperatively. Radiographic monitoring was performed at 30, 60 and 90 days postoperatively, and bone healing was observed without any complications. It is concluded that the treatment of humerus fractures in giant anteaters requires robust fixation. The use of a reinforced locking compression plate system proved to be effective and adequate to the mechanical load that an adult individual of this species needs for early use of the thoracic limb and, at the same time, efficient in controlling interfragmentary movement, which allowed fracture consolidation.(AU)


O tratamento das fraturas do membro torácico dos tamanduás-bandeira (Myrmecophaga tridactyla) é extremamente desafiador. Características anatômicas pouco familiares e peculiares, musculatura muito desenvolvida e necessidade iminente de retorno precoce à função do membro destacam tais desafios. Objetivou-se, neste relato, descrever a utilização com sucesso da osteossíntese anatômica com placa bloqueada robusta em fratura umeral de um tamanduá-bandeira. O paciente foi resgatado em rodovia após atropelamento e atendido no Hospital Veterinário Universitário. Após sedação e avaliação física completa, foi realizado exame radiográfico, o qual revelou fratura completa oblíqua curta em diáfise média de úmero esquerdo. A estabilização cirúrgica foi realizada por abordagem craniomedial ao úmero, utilizando-se placa bloqueada (LCP) do sistema 3,5mm customizada. O paciente apresentou apoio precoce do membro com 24 horas de pós-operatório. Realizou-se acompanhamento radiográfico aos 30, 60 e 90 dias, sendo observada união clínica sem quaisquer complicações. Conclui-se que o tratamento das fraturas do úmero em tamanduás-bandeira exige robustez na fixação. A utilização de sistema reforçado de placa bloqueada mostrou-se efetiva e adequada à carga mecânica de que um indivíduo adulto dessa espécie necessita para uso precoce do membro torácico e, ao mesmo tempo, eficiente no controle da movimentação interfragmentária, o qual permitiu consolidação da fratura.(AU)


Assuntos
Animais , Consolidação da Fratura , Eutérios/cirurgia , Fixação Interna de Fraturas/métodos , Fixação Interna de Fraturas/veterinária , Fraturas do Úmero/cirurgia , Fraturas do Úmero/veterinária , Placas Ósseas/veterinária , Animais Selvagens/cirurgia
5.
Neuropathol Appl Neurobiol ; 46(3): 240-254, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31216593

RESUMO

AIMS: In the search for blood-based biomarkers of neurodegenerative diseases, we characterized the concentration of total prion protein (t-PrP) in the plasma of neurodegenerative dementias. We aimed to assess its accuracy in this differential diagnostic context. METHODS: Plasma t-PrP was measured in 520 individuals including healthy controls (HC) and patients diagnosed with neurological disease control (ND), Alzheimer's disease (AD), sporadic Creutzfeldt-Jakob disease (sCJD), frontotemporal dementia (FTD), Lewy body dementia (LBD) and vascular dementia (VaD). Additionally, t-PrP was quantified in genetic prion diseases and iatrogenic CJD. The accuracy of t-PrP discriminating the diagnostic groups was evaluated and correlated with demographic, genetic and clinical data in prion diseases. Markers of blood-brain barrier impairment were investigated in sCJD brains. RESULTS: Compared to HC and ND, elevated plasma t-PrP concentrations were detected in sCJD, followed by FTD, AD, VaD and LBD. In sCJD, t-PrP was associated neither with age nor sex, but with codon 129 PRNP genotype. Plasma t-PrP concentrations correlated with cerebrospinal fluid (CSF) markers of neuro-axonal damage, but not with CSF t-PrP. In genetic prion diseases, plasma t-PrP was elevated in all type of mutations investigated. In sCJD brain tissue, extravasation of immunoglobulin G and the presence of swollen astrocytic end-feet around the vessels suggested leakage of blood-brain barrier as a potential source of increased plasma t-PrP. CONCLUSIONS: Plasma t-PrP is elevated in prion diseases regardless of aetiology. This pilot study opens the possibility to consider plasma t-PrP as a promising blood-based biomarker in the diagnostic of prion disease.


Assuntos
Biomarcadores/sangue , Demência/diagnóstico , Doenças Neurodegenerativas/diagnóstico , Doenças Priônicas/diagnóstico , Proteínas Priônicas/sangue , Adulto , Idoso , Demência/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Neurodegenerativas/sangue , Doenças Priônicas/sangue
6.
Arq. bras. med. vet. zootec. (Online) ; 70(6)nov.-dez. 2018. ilus, graf, tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-970336

RESUMO

Objetivou-se com este trabalho comparar biomecanicamente os posicionamentos dorsal e medial da placa bloqueada na artrodese do carpo em cães. Para isso, foram utilizados sete pares de membros torácicos de cães eutanasiados por razões não relacionadas ao estudo, em que sete membros foram estabilizados com placa dorsal, e seus respectivos pares com placa em posicionamento medial. Os membros com as articulações radiocarpometacarpianas estabilizadas cirurgicamente foram submetidos a ensaio de compressão axial em máquina universal de ensaios de materiais, e os dados de limite de elasticidade, rigidez estrutural, carga máxima e carga no momento da fratura dos posicionamentos foram comparados por meio do teste de Student-Newman-Keuls, a um nível de significância de 5%. Todos os membros foram fraturados no terço distal do terceiro metacarpo; nos membros com placa dorsal, a fratura ocorreu distal ao orifício distal e, nos membros com placa medial, a fratura ocorreu no último orifício dos metacarpos dois e três. Não houve dobra ou quebra de placas e parafusos e não houve diferença significativa entre os posicionamentos dorsal e medial dos implantes quanto aos parâmetros avaliados.(AU)


The aim of this study was to compare biomechanically the dorsal and medial positions of the locking plates on carpal arthrodesis in dogs. For this, seven pairs of thoracic limbs of dogs were used, in which seven limbs were stabilized with dorsal plate and seven limbs with plate in medial positioning. The members with the surgically stabilized radiocarpal-metacarpal joints were submitted to axial compression testing in a universal testing machine and the yield load, structural rigidity, maximum load and ultimate load of the positioning were compared by Student-Newman-Keuls test at a significance level of 5%. All members fractured in the distal third of the third metacarpal, in the limbs with dorsal plate the fracture occurred distal to the distal hole and in the members with medial plate the fracture occurred in the last hole of the metacarpals two and three. There was no bending or broken implants. There was no significant biomechanical differencebetween the dorsal and medial positions of the implants.(AU)


Assuntos
Animais , Cães , Artrodese/veterinária , Fenômenos Biomecânicos , Cães/anormalidades
7.
Phys Rev E ; 94(6-1): 062602, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28085454

RESUMO

Depletion forces exerted by self-propelled particles on circular and elliptical passive objects are studied using numerical simulations. We show that a bath of active particles can induce repulsive and attractive forces which are sensitive to the shape and orientation of the passive objects (either horizontal or vertical ellipses). The resultant force on the passive objects due to the active particles is studied as a function of the shape and orientation of the passive objects, magnitude of the angular noise, and distance between the passive objects. By increasing the distance between obstacles the magnitude of the repulsive depletion force increases, as long as such a distance is less than one active particle diameter. For longer distances, the magnitude of the force always decreases with increasing distance. We also found that attractive forces may arise for vertical ellipses at high enough area fraction.

8.
Artigo em Inglês | MEDLINE | ID: mdl-24730841

RESUMO

Diffusive properties of interacting magnetic dipoles confined in a parabolic narrow channel and in the presence of a periodic modulated (corrugated) potential along the unconfined direction are studied using Brownian dynamics simulations. We compare our simulation results with the analytical result for the effective diffusion coefficient of a single particle by Festa and d'Agliano [Physica A 90, 229 (1978)] and show the importance of interparticle interaction on the diffusion process. We present results for the diffusion of magnetic dipoles as a function of linear density, strength of the periodic modulation and commensurability factor.

9.
Artigo em Inglês | MEDLINE | ID: mdl-24730844

RESUMO

The ground state of colloidal magnetic particles in a modulated channel are investigated as a function of the tilt angle of an applied magnetic field. The particles are confined by a parabolic potential in the transversal direction while in the axial direction a periodic substrate potential is present. By using Monte Carlo simulations, we construct a phase diagram for the different crystal structures as a function of the magnetic field orientation, strength of the modulated potential, and the commensurability factor of the system. Interestingly, we found first- and second-order phase transitions between different crystal structures, which can be manipulated by the orientation of the external magnetic field. A reentrant behavior is found between two- and four-chain configurations, with continuous second-order transitions. Novel configurations are found consisting of frozen solitons of defects. By changing the orientation and/or strength of the magnetic field and/or the strength and periodicity of the substrate potential, the system transits through different phases.

10.
Neuroscience ; 268: 236-46, 2014 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-24662848

RESUMO

Inflammation, oxidative and nitrosative stress underlie depression being assessed in rodents by the systemic administration of lipopolysacharide (LPS). There is an increasing body of evidence of an involvement of nitric oxide (NO) pathway in depression, but this issue was not investigated in LPS-induced model. Thus, herein we evaluated the effects of NO-pathway-modulating drugs, named aminoguanidine, l-NAME, sildenafil and l-arginine, on the behavioral (forced swimming test [FST], sucrose preference [SPT] and prepulse inhibition [PPI] of the startle) and neurochemical (glutathione [GSH], lipid peroxidation, IL-1ß) alterations in the prefrontal cortex, hippocampus and striatum as well as in BDNF levels in the hippocampus 24h after LPS (0.5mg/kg, i.p.) administration, a time-point related to depressive-like behavior. Twenty-four hours post LPS there was an increase in immobility time in the FST, decrease in sucrose preference and PPI levels accompanied by a decrease in GSH levels and an increase in lipid peroxidation, IL-1ß and hippocampal BDNF levels suggestive of a depressive-like state. The pretreatment with the NOS inhibitors, l-NAME and aminoguanidine as well as sildenafil prevented the behavioral and neurochemical alterations induced by LPS, although sildenafil and l-NAME were not able to prevent the increase in hippocampal BDNF levels induced by LPS. The iNOS inhibitor, aminoguanidine, and imipramine prevented all behavioral and neurochemical alterations induced by LPS. l-arginine did not prevent the alterations in immobility time, sucrose preference and GSH induced by LPS. Taken together our results show that the NO-cGMP pathway is important in the modulation of the depressive-like alterations induced by LPS.


Assuntos
Antidepressivos/farmacologia , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Transtorno Depressivo/tratamento farmacológico , Inibidores Enzimáticos/farmacologia , Piperazinas/farmacologia , Sulfonas/farmacologia , Animais , Arginina/farmacologia , Comportamento Animal/fisiologia , Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , GMP Cíclico/metabolismo , Transtorno Depressivo/metabolismo , Transtorno Depressivo/prevenção & controle , Modelos Animais de Doenças , Guanidinas/farmacologia , Imipramina/farmacologia , Interleucina-1beta/metabolismo , Lipopolissacarídeos , Masculino , Camundongos , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Purinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Citrato de Sildenafila
11.
Artigo em Inglês | MEDLINE | ID: mdl-23410331

RESUMO

The diffusion of a system of ferromagnetic dipoles confined in a quasi-one-dimensional parabolic trap is studied using Brownian dynamics simulations. We show that the dynamics of the system is tunable by an in-plane external homogeneous magnetic field. For a strong applied magnetic field, we find that the mobility of the system, the exponent of diffusion, and the crossover time among different diffusion regimes can be tuned by the orientation of the magnetic field. For weak magnetic fields, the exponent of diffusion in the subdiffusive regime is independent of the orientation of the external field.


Assuntos
Coloides/química , Difusão , Campos Magnéticos , Modelos Químicos , Reologia/métodos , Simulação por Computador , Tamanho da Partícula
12.
Phys Rev E Stat Nonlin Soft Matter Phys ; 85(3 Pt 1): 031147, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22587078

RESUMO

Diffusive properties of a monodisperse system of interacting particles confined to a quasi-one-dimensional channel are studied using molecular dynamics simulations. We calculate numerically the mean-squared displacement (MSD) and investigate the influence of the width of the channel (or the strength of the confinement potential) on diffusion in finite-size channels of different shapes (i.e., straight and circular). The transition from single-file diffusion to the two-dimensional diffusion regime is investigated. This transition [regarding the calculation of the scaling exponent (α) of the MSD (Δx(2)(t) ∝ t(α)] as a function of the width of the channel is shown to change depending on the channel's confinement profile. In particular, the transition can be either smooth (i.e., for a parabolic confinement potential) or rather sharp (i.e., for a hard-wall potential), as distinct from infinite channels where this transition is abrupt. This result can be explained by qualitatively different distributions of the particle density for the different confinement potentials.


Assuntos
Algoritmos , Coloides/química , Difusão , Modelos Químicos , Modelos Moleculares , Nanopartículas/química , Simulação por Computador , Nanopartículas/ultraestrutura
13.
Br J Ophthalmol ; 93(5): 688-91, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19208678

RESUMO

AIMS: To compare the amount of intraoperative intraocular bleeding in patients with diabetes with macula-involving tractional retinal detachment (TRD) undergoing pars plana vitrectomy (PPV) with and without preoperative intravitreal bevacizumab (IVB) injection. METHODS: An institutional study was carried out with consecutive patients with diabetic retinopathy and macula-involving TRD of recent (3 months) onset who were randomly assigned to PPV only (PPV group) or PPV combined with one IVB (1.5 mg/0.06 ml) injection 2 weeks prior to surgery (bevacizumab (BEV)/PPV group). All patients underwent 23-gauge PPV 3 weeks after baseline. The main outcome measure was erythrocyte count in the fluid retrieved from the vitrectomy cassette using a Neubauer counting chamber. RESULTS: The study included 20 patients. The mean erythrocyte count was 14,865x10(3) (SD 19,332x10(3); median 4,500x10(3)) cells in the BEV/PPV group, and 176,240x10(3) (SD 108,375x10(3); median 166,600x10(3)) cells in the PPV group. The mean erythrocyte count was significantly lower in the BEV/PPV group than in the PPV group (p<0.0001). No major adverse events were identified. CONCLUSION: Preoperative IVB injection was associated with reduced intraocular bleeding during 23-gauge PPV for diabetic macula-involving TRD. Further studies are needed to confirm our preliminary findings. TRIAL REGISTRATION NUMBER: NCT00690768.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Perda Sanguínea Cirúrgica/prevenção & controle , Retinopatia Diabética/cirurgia , Descolamento Retiniano/cirurgia , Vitrectomia/efeitos adversos , Adulto , Idoso , Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais Humanizados , Bevacizumab , Contagem de Eritrócitos , Feminino , Humanos , Injeções , Masculino , Pessoa de Meia-Idade , Medicação Pré-Anestésica , Estudos Prospectivos , Resultado do Tratamento , Corpo Vítreo
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