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GPR39 is a receptor involved in zincergic neurotransmission, and its role in regulating psychological functions is an active area of research. The purported roles of GPR39 at the cellular level include regulation of inflammatory and oxidative stress response, and modulation of GABAergic and endocannabinoid neurotransmission. GPR39 knock-out (KO) mice exhibit episodic-like and spatial memory (ELM and SM, respectively) deficits throughout their lifetime, and are similar in that respect to senescent wild-type (WT) conspecifics. Since a role for zinc has been postulated in neurodegenerative disorders, in this study we investigated the possibility of a pharmacological rescue of both types of declarative memory with memantine - a noncompetitive NMDAR antagonist used for slowing down dementia; or, a putative GPR39 agonist - TC-G 1008. First, we tested adult WT and GPR39KO male mice under acute 5 mg/kg memantine or vehicle treatment in an object recognition task designed to simultaneously probe the "what?", "where?" and "when?" components of ELM. Next, we investigated the impact of chronic memantine or TC-G 1008 on ELM and SM (Morris water maze, MWM) in both WT and GPR39KO mice. Following chronic experiments, we assessed with qRT-PCR hippocampal gene expression of targets previously associated with GPR39. We report: no effects of acute memantine on ELM; a tendency to improve the "where?" component of ELM in both WT and GPR39 KO mice following 12 days of memantine; and, a disruption of SM in GPR39KO mice after 24 days of memantine treatment. The latter result was associated with upregulation of Htr1a hippocampal expression.
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Memantina , Zinc , Animales , Masculino , Ratones , Expresión Génica , Hipocampo/metabolismo , Memantina/farmacología , Memantina/metabolismo , Ratones Noqueados , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Memoria Espacial , Zinc/metabolismoRESUMEN
Health-promoting effects of medicinal mushrooms have been postulated for centuries in folk medicine in Asia and Europe and are currently being verified by scientific research. Lion's mane (Hericium erinaceus, HE) is an arboreal medicinal mushroom that has been shown to improve short-term memory of healthy mice, and to modulate stress-coping strategies of rodents. HE shares bioactive compounds with other arboreal medicinal mushrooms such as the pink oyster mushroom (Pleurotus djamor, PDJ) and agarikon (Fomitopsis officinalis, FO), but their effects in vivo have not been investigated. The aim of this study was to compare the effects of dietary supplementation with HE, FO, or PDJ on long-term memory, anxiety-like behavior, and hippocampal gene expression of healthy male mice. CD-1 mice were fed with either control or mushroom-supplemented (2 mg/g of dry chow) diets for 40 days and underwent object novelty recognition and elevated plus maze tests before hippocampi collection. Only HE-supplemented animals displayed long-term memory (one sample t-test against chance level of novelty preference ratio). Supplementation had no effect on anxiety-like behavior, but its effect on the frequency of arm visits of the elevated plus maze apparatus was modulated by the amount of ingested food - an effect that was absent in control animals. We also observed that mice with higher weight gain had lower expression of Gsk3ß and Mtor in their hippocampi. We discuss the relevance of these results for rodent behavioral studies of dietary mushroom supplementation.
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Agaricus , Suplementos Dietéticos , Ratones , Masculino , Animales , Memoria a Largo Plazo , AsiaRESUMEN
Swelling and shrinkage anisotropy affect the susceptibility to an assembly of wooden elements by changing designed clearances or interference fits. This work described the new method to measure mounting holes' moisture-induced shape instability and its verification using three sets of twin samples made of Scots pinewood. Each set of samples contained a pair with different grain patterns. All samples were conditioned under reference conditions (relative air humidity-RH = 60% and temperature 20 °C), and their moisture content (MC) reached equilibrium (10.7 ± 0.1%). On the side of each sample, the seven mounting holes of 12 mm in diameter were drilled. Immediately after drilling, Set 1 was used to measure the effective hole diameter with 15 cylindrical plug-gauges with diameters of 0.05 mm step, while Set 2 and Set 3 were separately re-seasoned by six months in two extreme conditions. Set 2 was conditioned with air at 85% RH (reached an equilibrium MC of 16.6 ± 0.5%), while Set 3 was exposed to air at 35% RH (reached an equilibrium MC of 7.6 ± 0.1%). Results of the plug gauge tests highlighted that holes in the samples subjected to swelling (Set 2) increased an effective diameter in the range of 12.2-12.3 mm (1.7-2.5%), while samples subjected to shrinking (Set 3) reduced the effective diameter to 11.9-11.95 mm (0.8-0.4%). To accurately reproduce the complex shape of the deformation, gypsum casts of holes were made. The 3D optical scanning method was used to read the gypsum casts' shape and dimensions. The 3D surface map of deviations analysis provided more detailed information than the plug-gauge test results. Both the shrinking and swelling of the samples changed the shapes and sizes of the holes, but shrinking reduced the effective diameter of the hole more than swelling increased it. The moisture-induced changes in the shape of holes are complex: the holes ovalized with a different range, depending on the wood grain pattern and hole depth, and were slightly extended in diameter at the bottom. Our study provides a new way to measure 3D hole initial shape changes in wooden elements during desorption and absorption.
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PURPOSE: Among various test methods for different human joints, the use of robot systems has attracted major interest and inherits the potential to become a gold standard in biomechanical testing in the future. A key issue associated with those robot-based platforms is the accurate definition of parameters, e.g., tool center point (TCP), length of tool or anatomical trajectories of movements. These must be precisely correlated to the physiological parameters of the examined joint and its corresponding bones. Exemplified for the human hip joint, we are creating an accurate calibration procedure for a universal testing platform by using a six degree-of-freedom (6 DOF) robot and optical tracking system for recognition of anatomical movements of the bone samples. METHODS: A six degree-of-freedom robot (TX 200, Stäubli) has been installed and configured. The physiological range of motion of the hip joint composed of a femur and a hemipelvis was recorded with an optical 3D movement and deformation analysis system (ARAMIS, GOM GmbH). The recorded measurements were processed by automatic transformation procedure (created in Delphi software) and evaluated in 3D CAD system. RESULTS: The physiological ranges of motion were reproduced for all degrees of freedom with the six degree-of-freedom robot in adequate accuracy. With the establishment of a special calibration procedure by using a combination of different coordinate systems, we were able to achieve a standard deviation of the TCP depending of the axis between 0.3 and 0.9 mm and for the length of tool between + 0.67 and - 0.40 mm (3D CAD processing) resp. + 0.72 mm to - 0.13 mm (Delphi transformation). The accuracy between the manual and robotic movement of the hip shows an average deviation between - 0.36 and + 3.44 mm for the points on the movement trajectories. CONCLUSION: A six degree-of-freedom robot is appropriate to reproduce the physiological range of motion of the hip joint. The described calibration procedure is universal and can be used for hip joint biomechanical tests allowing to apply clinically relevant forces and investigate testing stability of reconstructive osteosynthesis implant/endoprosthetic fixations, regardless of the length of the femur, size of the femoral head and acetabulum or whether the entire pelvis or only the hemipelvis will be used.
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Procedimientos Quirúrgicos Robotizados , Humanos , Calibración , Articulación de la Cadera , Acetábulo , FémurRESUMEN
Referred pain/sensation provoked by trigger points suits the nociplastic pain criteria. There is a debate over whether trigger points are related to a peripheral phenomenon or central sensitization (CS) processes. Referred pain is considered a possible sign of CS, which occurs probably mainly due to the abnormal activity of the immune and autonomic nervous systems. To confirm abnormal autonomic reactivity within the referred pain zone of active trigger points, a new diagnostic tool, the Skorupska Protocol® (the SP test®), was applied. The test uses noxious stimulation (10 minutes of dry needling under infrared camera control) as a diagnostic tool to confirm abnormal autonomic nervous system activity. A response to the SP test® of healthy subjects with referred pain sensations provoked by latent trigger points (LTrPs) stimulation was not explored before. The study aims at examining if LTrPs can develop an autonomic response. Methods. Two groups of healthy subjects, (i) gluteus minimus LTrPs with referred pain (n = 20) and (ii) control (n = 27), were examined using the SP test®. Results. Abnormal autonomic activity within the referred pain zone was confirmed for all analyzed LTrPs subjects. 70% of control subjects had no feature of vasodilatation and others presented minor vasomotor fluctuations. The size of vasomotor reactivity within the referred pain zone was LTrPs 11.1 + 10.96% vs. control 0.8 + 0.6% (p < 0.05). Conclusions. Noxious stimulation of latent TrPs induces abnormal autonomic nervous system activity within the referred pain zone. The observed phenomenon supports the concept of central nervous system involvement in the referred pain patomechanizm.
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Síndromes del Dolor Miofascial , Dolor Referido , Humanos , Sensibilización del Sistema Nervioso Central , Músculo Esquelético , Puntos Disparadores , Sistema Nervioso AutónomoRESUMEN
As a neuromodulator, zinc regulates synaptic plasticity, learning and memory. Synaptic zinc is also a crucial factor in the development of toxic forms of amyloid beta protein and, subsequently, of Alzheimer's dementia (AD). Therefore, efforts to pinpoint mechanisms underlying zinc-dependent cognitive functions might aid AD research, by providing potential novel targets for drugs. One of the most understudied proteins in this regard is a zinc-sensing metabotropic receptor: GPR39. In this study we investigated the impact of GPR39 knock-out (KO) on age-related memory decline in mice of both sexes, by comparing them to age-matched wild-type (WT) littermates. We also tested the effects of a GPR39 agonist (TC-G 1008) on declarative memory of old animals, and its disruption in adult mice. We observed episodic-like memory (ELM) and spatial memory (SM) deficits in male GPR39 KO mice, as well as intact procedural memory in GPR39 KO mice regardless of age and sex. ELM was also absent in old WT male mice, and all female mice regardless of their genotype. Acute application of TC-G 1008 (10 mg/kg) reversed a deficit in two of three ELM components in old WT male mice, and had no promnesic effect on consolidation interference of ELM in adult WT mice. We discuss the possible neurobiological mechanisms and the translational value of these results for potential add-on pharmacotherapy of AD aimed at the zinc-sensing receptor.
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Enfermedad de Alzheimer , Zinc , Ratones , Masculino , Femenino , Animales , Zinc/metabolismo , Péptidos beta-Amiloides/metabolismo , Hipocampo/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Ratones Noqueados , Trastornos de la Memoria/tratamiento farmacológico , Trastornos de la Memoria/metabolismo , Proteínas Portadoras/metabolismo , Enfermedad de Alzheimer/metabolismo , Expresión Génica , Modelos Animales de EnfermedadRESUMEN
Gluteal syndrome (GS) mimicking sciatica is a new disease that has been recently recognized and included in the International Classification of Diseases, 11th Revision. The present study examines nociplastic pain involvement in GS and sciatica patients using a new Skorupska protocol (SP) test that provokes amplified vasodilatation in the area of expected muscle-referred pain. A positive test is confirmed if there is (i) a development of autonomic referred pain (AURP) and (ii) an increase in the delta of average temperature (Δ⸰) > 0.3 °C at the end of the stimulation and during the observation SP phases. Chronic GS (n = 20) and sciatica (n = 30) patients were examined. The SP test confirmed muscle-referred pain for (i) all GS patients with 90.6% positive thermograms (Δ⸰ 0.6 ± 0.8 °C; maximum AURP 8.9 ± 13.6% (both p < 0.05)) and (ii) those sciatica (n = 8) patients who reported pain sensation during the test with 20.6% positive thermograms (Δ⸰ 0.7 ± 0.7 °C; maximum AURP 15.1 ± 17.8% (both p < 0.05)). The remaining sciatica (n = 22) patients did not report pain during the test and presented a Δ⸰ decrease and the AURP size below 1%. Conclusion: Amplified vasodilatation suggesting nociplastic pain involvement was confirmed for all GS and sciatica patients who reported painful sensations in the zone typical for gluteus minimus referred pain during the test.
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The trigger points (TrPs) related to chronic low back pain that mimic sciatica have been lately recognized and included in the International Classification of Diseases, 11th Revision. This study examined the MATLAB software utility for the objective stratification of low back pain patients using the Minimally Invasive Procedure (MIP). The two diagnostic MIP parameters were: average temperature (ΔTavr) and autonomic referred pain (AURP). Chronic sciatica patients with TrPs (n = 20) and without TrPs (n = 20) were examined using the MIP. A significant increase in both parameters was confirmed for the thigh ROI of the TrP-positive patients, with ΔTavr being the leading parameter (p = 0.016, Exp(ß) = 2.603). A continued significance of both parameters was confirmed from 6'00â³ to 15'30â³ (p < 0.05). The maximum AURP value was confirmed at 13'30â³ (p < 0.05) (TrPs(+) 20.4 ± 19.9% vs. TrPs(-) 3.77 ± 9.14%; p = 0.000; CI (0.347,0.348)).
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AIM: To see if three-dimensional (3D) methods could bring new understanding to acetabular changes in shape and orientation in the spastic hip and in which direction(s) acetabular orientation might change, which is crucial for planning appropriate hip correction surgery. METHOD: We performed a retrospective study of pelvic computed tomography (CT) examinations in 20 consecutive patients (10 females, 10 males). The mean age of patients was 12 years 9 months (SD 2y; range: 9-16y) at the time of the CT examination. The control group consisted of 18 consecutive pelvic CT examinations (36 acetabula) of deceased individuals (six females, 12 males) aged 4 to 17 years (mean age: 10y 6mo; SD 5y 2mo) whose whole-body CT scans were taken shortly after their death. We compared 3D CT reconstructions of 28 unstable and dislocated hips in children with bilateral cerebral palsy (Gross Motor Function Classification System levels IV and V) with the unaffected side and typically developing controls to assess spatial orientation (inclination, anteversion, and tilt), acetabular volume, and surface area. Additionally, we analysed the multiple factors that may lead to structural and spatial changes of the acetabulum. RESULTS: Patients with dislocated and spastic hips had significantly lower anteversion (-3.2° and -1.4° respectively, p<0.001), increased inclination (85.2° and 85.3° respectively, p<0.001), and decreased tilt (24.6° [p=0.014] and 20.7° [p=0.013] respectively) compared with typically developing individuals. Regarding acetabular volume and surface area, dislocated and unstable hips had significantly lower volume (17.6ml vs 31.5ml respectively, p<0.001) and surface area (28.9cm2 vs 36.2cm2 respectively, p<0.001) than unaffected hips. Among several factors, only Reimer's migration index had an influence on acetabular orientation (i.e. anteversion, p=0.01), volume (p<0.001), and surface (p=0.004). INTERPRETATION: Acetabula in patients with spastic hip disease were severely retroverted with increased steepness; acetabular orientation was distorted superoposteriorly. In rare cases, acetabular orientation was distorted only superiorly or superoanteriorly. WHAT THIS PAPER ADDS: Acetabular orientation was distorted superoposteriorly in most patients with severe bilateral cerebral palsy. More pronounced acetabular changes were found in hips with a higher Reimer's migration index.
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Acetábulo/patología , Parálisis Cerebral/patología , Articulación de la Cadera/patología , Acetábulo/diagnóstico por imagen , Adolescente , Parálisis Cerebral/diagnóstico por imagen , Niño , Preescolar , Femenino , Articulación de la Cadera/diagnóstico por imagen , Humanos , Imagenología Tridimensional , Masculino , Estudios Retrospectivos , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND: The newly proposed low back pain treatment requires case classification according to the pain mechanism (nociceptive, neuropathic or nociplastic) to determine the most effective therapeutic approach. However, there is a lack of objective tools for distinguishing these pain mechanisms. The aim of the study was to identify which symptoms, signs, and standard diagnostic parameters would allow predicting the nociplastic pain (NP) subtype among low back leg pain (LBLP) patients. METHODS: A retrospective analysis of an LBLP case-control study database was carried out. The presence of NP was assumed if the patient presented with myofascial pain syndrome (MPS) and developed a short-term intensive vasodilatation reaction in the perceived lower leg pain area after provocation by a minimally invasive procedure. Clinical data and standard LBLP diagnostic parameters were analyzed to classify patients as NP (+) vs NP (-). Next, to predict NP probability, logistic regression analysis and a diagnostic classification tree were constructed. RESULTS: NP was confirmed in 43.75% of LBLP patients. Women represented 95.24% of all NP (+) patients. The diagnostic classification tree indicated that NP was highly probable if the LBLP subject was female and the result of a positive straight leg raise (SLR) test was lower than 45 degrees. If the SLR test result was greater than or equal to 45 degrees, a negative result on the Bragard test would have diagnostic value. This classification tree was approved to a certain extent in the logistic regression model (deviance residuals, min: -1.8519; 1Q: -0.5551; median: -0.1907; 3Q: 0.6565 and max: 2.1058) but should be verified in a larger group of subjects. CONCLUSION: Female sex, but not clinical data or standard diagnostic parameters, is indicative of nociplastic pain in LBLP patients. More sophisticated statistical methods, based on directly measurable parameters, should be proposed to distinguish NP involvement in LBLP.
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PURPOSE: The aim of this study is to assess the pelvis's morphology and spatial orientation of the acetabulum, and their relation to the severity of Congenital Femoral Deficiency (CFD) using 3D imaging. Defining these pathologies is crucial for adequate surgical correction. METHODS: The shape and structure of the acetabulum and pelvis were evaluated in 14 children with unilateral CFD via 3D computed tomography (CT) scans, and then analysed with geometric morphometrics (Procrustes ANOVA). The association between pelvic directional asymmetry and CFD classifications (Aitken, Paley) was assessed. The affected acetabulum's orientation was compared to the non-affected side, and the variability of orientation in different CFD types was evaluated (bivariate correlation). RESULTS: The hemipelvis with CFD is characterized by a smaller acetabulum, a laterally curved ischium and a less upright ilium (p < 0.001). Multivariate regressions revealed a greater level of pelvis asymmetry in more severe types of CFD (p < 0.001). The acetabulum orientation assessment showed a significant decrease in mean anteversion (1.3°) and inclination (9.6°) angle, when compared to the non-affected side (26°and 17.1° respectively; p < 0.001). CONCLUSIONS: The affected side of the pelvis is considerably smaller and more deformed, and this should be considered during limb lengthening. The acetabulum presents with significant dysplasia due to its severe retroversion and steepness (superoposterior distortion). This should not be interpreted as a simple wall deficit, but as a complete acetabular misalignment (often misinterpreted in 2D imagery). Using transiliac osteotomies (e.g. Dega, Salter) is debatable due to abnormal acetabular orientation (superoposterior malalignment). Therefore, alternative options, e.g. San Diego or triple pelvic osteotomy, should be considered.
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With more people reaching an advanced age in modern society, there is a growing need for strategies to slow down age-related neuropathology and loss of cognitive functions, which are a hallmark of Alzheimer's disease. Neuroprotective drugs and candidate drug compounds target one or more processes involved in the neurodegenerative cascade, such as excitotoxicity, oxidative stress, misfolded protein aggregation and/or ion dyshomeostasis. A growing body of research shows that a G-protein coupled zinc (Zn2+) receptor (GPR39) can modulate the abovementioned processes. Zn2+itself has a diverse activity profile at the synapse, and by binding to numerous receptors, it plays an important role in neurotransmission. However, Zn2+ is also necessary for the formation of toxic oligomeric forms of amyloid beta, which underlie the pathology of Alzheimer's disease. Furthermore, the binding of Zn2+ by amyloid beta causes a disruption of zincergic signaling, and recent studies point to GPR39 and its intracellular targets being affected by amyloid pathology. In this review, we present neurobiological findings related to Zn2+ and GPR39, focusing on its signaling pathways, neural plasticity, interactions with other neurotransmission systems, as well as on the effects of pathophysiological changes observed in Alzheimer's disease on GPR39 function. Direct targeting of the GPR39 might be a promising strategy for the pharmacotherapy of zincergic dyshomeostasis observed in Alzheimer's disease. The information presented in this article will hopefully fuel further research into the role of GPR39 in neurodegeneration and help in identifying novel therapeutic targets for dementia.
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Enfermedad de Alzheimer/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Zinc/metabolismo , Animales , Sistema Nervioso Central/fisiopatología , Humanos , Redes y Vías MetabólicasRESUMEN
OBJECTIVES: The study aimed to compare the accuracy of different methods of data acquisition and data reconstruction and to assess their usefulness for 3D printing of tooth replicas. METHODS: 3-dimensional models of molar and canine teeth obtain utilizing CBCT examination with different protocols, and optical scanning was compared with models derived from micro-computed (micro-CT) examination using Geomagic Studio Qualify software. A pairwise comparison of 3D models with analysis of standard deviation and the value of the mean distance of given surfaces was performed. RESULTS: Standard deviation and the value of the mean distance were lowest for optical scanning followed by CBC in high and standard resolution in all tested protocols. Models, obtained with high-resolution CBCT protocols, of teeth in and outside of alveolar bone showed similar average distance parameters, but standard deviation parameter was significantly lower for models of teeth scanned outside of the socket. Good surface representation on all models was seen at relatively smooth areas while in areas of high changes in the geometry CBCT based models performed inferiorly to those obtained from an optical scanner. CONCLUSIONS: In case of teeth of noncomplicated texture, independently from a position (within or outside the alveolar socket), the high-resolution CBCT seems to be a sufficient method to obtain data for 3D printed tooth replica. Optical scanning performs better when a detailed replica is necessary.
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Imagenología Tridimensional , Imagen Óptica , Tomografía Computarizada por Rayos X , Diente/diagnóstico por imagen , Animales , Tomografía Computarizada de Haz Cónico , Perros , Humanos , Modelos Dentales , Microtomografía por Rayos XRESUMEN
BACKGROUND: The significantly accelerated development of human society in the last millennium has brought about changes in human behavior and body mass that may have influenced human bone morphology. Our objective was to analyze the variation in pelvic shape and size in males from modern and medieval populations. METHODS: We obtained 22 pelvic girdles of adult males from a medieval cemetery located in Cedynia, Poland. The control group comprised 31 contemporary male pelves from individuals inhabiting the same region. The analyzed parameters were: interspinous distance (ISD), intercristal distance (ICD), intertuberous distance (ITD), anatomic conjugate of the pelvis, height of the pelvis (HP), iliac opening angle (IOA), iliac tilt angle (ITA), and ISD/ITD/HP ratio. Geometric morphometrics was used to analyze differences in shape in the pelves. All analyses were carried out on three-dimensional CT reconstructions of pelves. RESULTS: ISD, ICD, and IOA were significantly greater in modern pelves than in those from Cedynia, but no significant differences were seen between the two groups in ITD, anatomical conjugate, HP, or ITA. ISD/ITD/HP ratios were significantly lower in the Cedynia group. Geometric morphometrics revealed significant differences in pelvic shape between the analyzed groups. DISCUSSION: The pelves of modern males are larger, wider, and flatter than those of medieval males. Changes in the set of daily activities that produce mechanical loading and estimated body mass may constitute the main factors explaining pelvic variability. However, differences in ontogenesis should also be taken into consideration, especially since growth in past populations is often found to be reduced relative to modern populations.
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Depressive disorders are often associated with cognitive biases. In this study, we investigated, in an animal model, whether cognitive judgement bias, measured as a stable and enduring behavioural trait, could modulate the effects of antidepressant drugs on other cognitive processes associated with depression. For this purpose, we identified rats displaying 'pessimistic' and 'optimistic' traits in a series of ambiguous-cue interpretation (ACI) tests. Subsequently, in the preclinical version of the probabilistic reversal-learning (PRL) test, allowing multiple reversals within a test session, we compared the effects of acute administration of 5 different antidepressant (AD) drugs (agomelatine, escitalopram, clomipramine, mirtazapine and venlafaxine) on cognitive flexibility and sensitivity to positive/negative feedback in optimistic and pessimistic animals. We report that, following acute treatment with agomelatine, the proportion of lose-shift behaviours in the PRL test was significantly reduced in pessimistic animals compared to optimists. We also demonstrate that acute treatment with another antidepressant drug, mirtazapine, significantly increased the sensitivity of rats to positive feedback, as indexed by the increased proportion of win-stay behaviour following probabilistic reward. This effect was independent of cognitive bias and was associated with a reduced number of reversals made by the animals. Three other tested drugs had no significant effects on behavioural measures assessed in our study.
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Antidepresivos/farmacología , Retroalimentación Psicológica/efectos de los fármacos , Optimismo , Pesimismo , Aprendizaje por Probabilidad , Aprendizaje Inverso/efectos de los fármacos , Acetamidas/farmacología , Animales , Cognición/efectos de los fármacos , Función Ejecutiva/efectos de los fármacos , Juicio/efectos de los fármacos , Masculino , Personalidad/efectos de los fármacos , Pruebas Psicológicas , Ratas Sprague-Dawley , RecompensaRESUMEN
RATIONALE: Depression is characterized by an excessive attribution of value to negative feedback. This imbalance in feedback sensitivity can be measured using the probabilistic reversal-learning (PRL) task. This task was initially designed for clinical research, but introduction of its rodent version provides a new and much needed translational paradigm to evaluate potential novel antidepressants. OBJECTIVES: In the present study, we aimed at evaluating the effects of a compound showing clear antidepressant properties-ketamine (KET)-on the sensitivity of rats to positive and negative feedback in the PRL paradigm. METHODS: We trained healthy rats in an operant version of the PRL task. For successful completion of the task, subjects had to learn to ignore infrequent and misleading feedback, arising from the probabilistic (80:20) nature of the discrimination. Subsequently, we evaluated the effect of KET (5, 10, and 20 mg/kg) on feedback sensitivity 1, 24, and 48 h after administration. RESULTS: We report that acute administration of the highest dose of KET (20 mg/kg) rapidly and persistently decreases the proportion of lose-shift responses made by rats after receiving negative feedback. CONCLUSION: Present results suggest that KET decreases negative feedback sensitivity and that changes in this basic neurocognitive function might be one of the factors responsible for its antidepressant action.
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Antidepresivos/farmacología , Ketamina/farmacología , Aprendizaje Inverso/efectos de los fármacos , Animales , Relación Dosis-Respuesta a Droga , Masculino , Ratas , Ratas Sprague-DawleyRESUMEN
Although the cognitive theory has implicated judgment bias in various psychopathologies, its role in decision making under risk remains relatively unexplored. In the present study, we assessed the effects of cognitive judgment bias on risky choices in rats. First, we trained and tested the animals on the rat version of the probability-discounting (PD) task. During discrete trials, the rats chose between two levers; a press on the "small/certain" lever always resulted in the delivery of one reward pellet, whereas a press on the "large/risky" lever resulted in the delivery of four pellets. However, the probability of receiving a reward from the "large/risky" lever gradually decreased over the four trial blocks. Subsequently, the rats were re-trained and evaluated on a series of ambiguous-cue interpretation (ACI) tests, which permitted their classification according to the display of "optimistic" or "pessimistic" traits. Because dopamine (DA) has been implicated in both: risky choices and optimism, in the last experiment, we compared the reactivity of the dopaminergic system in the "optimistic" and "pessimistic" animals using the apomorphine (APO; 2 mg/kg s.c.) sensitivity test. We demonstrated that as risk increased, the proportion of risky lever choices decreased significantly slower in "optimists" compared with "pessimists" and that these differences between the two groups of rats were associated with different levels of dopaminergic system reactivity. Our findings suggest that cognitive judgment bias, risky decision-making and DA are linked, and they provide a foundation for further investigation of the behavioral traits and cognitive processes that influence risky choices in animal models.
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AIM: Lately, the diagnostic value of magnetic resonance imaging, Lasègue sign and classic neurological signs have been considered not accurate enough to distinguish the radicular from non-radicular low back with leg pain (LBLP) and a calculation of the symptomatic side muscle volume has been indicated as a probable valuable marker. However, only the multifidus muscle volume has been calculated so far. The main objective of the study was to verify whether LBLP subjects presented symptomatic side pelvic muscle atrophy compared to healthy volunteers. The second aim was to assess the inter-rater reliability of 3-D manual method for segmenting and measuring the volume of the gluteus maximus, gluteus medius, gluteus minimus and piriformis muscles in both LBLP patients and healthy subjects. METHOD: Two independent raters analyzed MR images of LBLP and healthy subjects towards muscle volume of four pelvic muscles, i.e. the piriformis, gluteus minimus, gluteus medius and gluteus maximus. For both sides, the MR images of the muscles without adipose tissue infiltration were manually segmented in 3-D medical images. RESULTS: Symptomatic muscle atrophy was confirmed in only over 50% of LBLP subjects (gluteus maximus (p<0.001), gluteus minimus (p<0.01) and piriformis (p<0.05)). The ICC values indicated that the inter-rater reproducibility was greater than 0.90 for all measurements (LBLP and healthy subjects), except for the measurement of the right gluteus medius muscle in LBLP patients, which was equal to 0.848. CONCLUSION: More than 50% of LBLP subjects presented symptomatic gluteus maximus, gluteus minimus and piriformis muscle atrophy. 3-D manual segmentation reliably measured muscle volume in all the measured pelvic muscles in both healthy and LBLP subjects. To answer the question of what kind of muscle atrophy is indicative of radicular or non-radicular pain further studies are required.
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Imagenología Tridimensional , Pierna , Dolor de la Región Lumbar/diagnóstico , Imagen por Resonancia Magnética , Músculo Esquelético/patología , Músculo Esquelético/fisiopatología , Pelvis/patología , Estudios de Casos y Controles , Humanos , Examen Neurológico , Tamaño de los Órganos , Reproducibilidad de los ResultadosRESUMEN
BACKGROUND: Although acetabulum orientation is well established anatomically and radiographically, its relation to the innominate bone has rarely been addressed. If explored, it could open the discussion on patomechanisms of such complex disorders as femoroacetabular impingement (FAI). We therefore evaluated the influence of pelvic bone position and structure on acetabular spatial orientation. We describe this relation and its clinical implications. METHODS: This retrospective study was based on computed tomography scanning of three-dimensional models of 31 consecutive male pelvises (62 acetabulums). All measurements were based on CT spatial reconstruction with the use of highly specialized software (Rhinoceros). Relations between acetabular orientation (inclination, tilt, anteversion angles) and pelvic structure were evaluated. The following parameters were evaluated to assess the pelvic structure: iliac opening angle, iliac tilt angle, interspinous distance (ISD), intertuberous distance (ITD), height of the pelvis (HP), and the ISD/ITD/HP ratio. The linear and nonlinear dependence of the acetabular angles and hemipelvic measurements were examined with Pearson's product - moment correlation and Spearman's rank correlation coefficient. Correlations different from 0 with p < 0.05 were considered statistically significant. RESULTS: Comparison of the axis position with pelvis structure with orientation in the horizontal plane revealed a significant positive correlation between the acetabular anteversion angle and the iliac opening angle (p = 0.041 and 0.008, respectively). In the frontal plane, there was a positive correlation between the acetabular inclination angle and the iliac tilt angle (p = 0.025 and 0.014, respectively) and the acetabular inclination angle and the ISD/ITD/HP ratio (both p = 0.048). CONCLUSIONS: There is a significant correlation of the hemipelvic structure and acetabular orientation under anatomic conditions, especially in the frontal and horizontal planes. In the anteroposterior view, the more tilted-down innominate bone causes a more caudally oriented acetabulum axis, whereas in the horizontal view this relation is reversed. This study may serve as a basis for the discussion on the role of the pelvis in common disorders of the hip.
Asunto(s)
Acetábulo/diagnóstico por imagen , Tomografía Computarizada Multidetector , Huesos Pélvicos/diagnóstico por imagen , Puntos Anatómicos de Referencia , Humanos , Imagenología Tridimensional , Masculino , Modelos Anatómicos , Interpretación de Imagen Radiográfica Asistida por Computador , Estudios Retrospectivos , Programas InformáticosRESUMEN
BACKGROUND: The study aimed to compare sex differences in the morphology and spatial orientation of pelvic acetabula to advance the understanding of hip anatomy. MATERIAL AND METHODS: The study was based on three-dimensional reconstructions of computed tomography images of 50 female and 50 male acetabula. The images were used for spatial analysis of hip acetabula relative to the base of the sacral bone as the plane of reference. Statistical analysis was performed to compare angles relevant to the actual axis of the acetabulum (inclination angle, anteversion angle, tilt angle) as well as the volume and inner surface area of the acetabulum. RESULTS: Both the inclination and tilt angles of the acetabulum did not differ significantly between the groups, the respective values being: 68.61° and 26.53° in females and 70.56° and 30.19° in males (p>0.05). The anteversion angle was significantly larger for female acetabula (38.27° compared to 32.05° in men, with p=0.0008), while the volume and the inner surface area were significantly smaller in women (p=0.0007 and 0.0001 respectively). CONCLUSIONS: 1. Acetabular orientation is sex-specific, with female acetabula being more forward-oriented than those of men. 2. The volume and inner surface area of acetabula also differ between the sexes, being smaller in women. 3. Regardless of the plane of reference, sexual dimorphism of the acetabulum is constant. 4. Awareness of the above sex-dependent differences is necessary for preoperative planning before orthopaedic surgeries (such as hip arthroplasty or operative treatment of FAI).