ABSTRACT
The objectives of our study were 1) to examine whether the force-velocity-power (FvP) outcomes in the concentric and eccentric phases of flywheel (FW) squats differ among sports disciplines and 2) to investigate the association between FvP outcome variables and two key sport-performance indicators: countermovement jump height (CMJ) and change of direction (CoD) time involving 90° or 180° turns. Tests were performed by 469 athletes from five different sport disciplines and physical education students. Our results showed that FvP outcomes, when measured during the eccentric phase of the FW squat, effectively differed between athletes from different sports. However, during the concentric phase of the squat, only for the slope variable differences between sports were found. Contrary to our hypothesis, there were no statistically significant correlations between FW squat FvP outcomes and CMJ or CoD test results. These results suggest that FvP outcomes derived from FW squats may lack external validity and cannot be reliably used as a predictor of athletes' jumping and agility performance. The paper discusses possible reasons for the larger differences between sports in eccentric FvP outcomes, as well as the absence of correlations between FvP outcomes and functional tests.
ABSTRACT
OBJECTIVES: This prospective cross-sectional study aimed to delineate associations between the performance and physiological responses to the Bruce test with two field tests, the futsal intermittent endurance test (FIET) and the Yo-Yo intermittent recovery test level-2 (YYIR2) in elite male futsal players, in order to endorse one of field test to futsal coaches. METHODS: Fifteen elite futsal players (age 20 ± 3 years) have been participated in this study. Main outcome measurements included aerobic power, heart rate, blood lactate, ventilation, VO2, VCO2, VE-VO2, and VE-VCO2 indicators during FIET, YYIR2, and the Bruce test with carrying out a portable gas analyzer. RESULTS: The Bruce test is significantly correlated with FIET and YYIR2 with respect to key outcome measures, including performance (r>0.59), aerobic power (r>0.69), heart rate (r>0.80), and blood lactate levels (r>0.60). The two field tests, FIET and YYIR2, were found to exhibit strong to perfect interrelationships. When examining the indicators such as VE, VO2, VCO2, VE-VO2, and VE-VCO2, moderate to strong correlations were identified across all three testing methods. However, the relationship between the Bruce test and YYIR2 was particularly noteworthy in terms of respiratory exchange ratio (RER) and metabolic equivalent of task (METS), showing a significant correlation. CONCLUSIONS: The YYIR2 and FIET appear to be valid practical field tests for measuring aerobic fitness and performance in competitive male futsal players.
ABSTRACT
OBJECTIVES: To compile a battery of test including various aspects of physical fitness that could be used on the field and to assess whether any of these tests are associated with future traumatic knee injuries in youth female team sports athletes. DESIGN: Prospective cohort. SETTING: Sport setting. PARTICIPANTS: Female athletes (n = 117, age 15-19 years), from Swedish sport high schools, active in soccer, handball, or floorball. MAIN OUTCOME MEASURES: Differences in pre-injury tests values of 11 physical fitness tests in injured versus non-injured athletes, assessed as number of traumatic knee injuries over one season. RESULTS: 28 athletes sustained 34 traumatic knee injuries. Athletes who sustained an injury had a shorter distance on the Yo-Yo IR1 test at baseline than those without an injury (mean difference -193 m, CI -293- -65 m). None of the other tests, assessed for muscular strength, endurance, power, flexibility and dynamic knee valgus, differed between injured and non-injured athletes. CONCLUSIONS: Youth female athletes with lower intermittent endurance capacity, assessed with the Yo-Yo IR1, seemed to be at greater risk of traumatic knee injury. Neither hop performance, flexibility, dynamic knee valgus nor isolated strength tests at baseline could distinguish between injured and non-injured youth female athletes at follow-up.
Subject(s)
Athletic Injuries , Knee Injuries , Physical Fitness , Humans , Female , Prospective Studies , Adolescent , Physical Fitness/physiology , Knee Injuries/physiopathology , Athletic Injuries/physiopathology , Young Adult , Exercise Test , Muscle Strength/physiology , Athletes , SwedenABSTRACT
Lithium supply risk is increasing and driving rapid progress in lithium recovery schemes from spent lithium-ion batteries (LIBs). In this study, a facile recycling process consisting mainly of reduction roasting and NaHCO3 leaching was adopted to improve lithium recovery. The Li of spent LiNixCoyMn1-x-yO2 powder were converted to Li2CO3 and LiAlO2 with the reduction effect of C and residual Al in the roasting process. NaHCO3 leaching was utilized to selectively dissolve lithium from Li2CO3 and water-insoluble LiAlO2. The activation energy of NaHCO3 leaching was 9.31 kJâmol-1 and the leaching of lithium was a diffusion control reaction. More than 95.19 % lithium was leached and recovered as a Li2CO3 product with a purity of 99.80 %. Thus, this approach provides a green path to selective recovery of lithium with good economics.
Subject(s)
Electric Power Supplies , Lithium , Recycling , Lithium/chemistry , Recycling/methods , Sodium Bicarbonate/chemistryABSTRACT
Semen cryopreservation is a crucial part of assisted reproductive techniques (ART) in animals, and recently it is gaining more and more attention among cat breeders. Even if fresh semen quality is good, sometimes spermatozoa do not survive freezing. The freezability prediction was widely studied in many species, but not in the domestic cat. The aim of this study was to verify the usefulness of osmotic challenge tests and membrane structure markers (Yo-Pro 1 and Merocyanine 540) for the prediction of the quality of post-thawed feline semen. Semen was collected by urethral catheterization from 22 male cats. After a basic evaluation of semen, 20×106 spermatozoa were cryopreserved; the rest were evaluated by flow cytometry for membrane integrity (SYBR-14/PI), acrosome status (lectin PNA/PI), mitochondrial potential (JC-1) and membrane stability (Yo-Pro 1/M540 staining). Hypo- and hyperosmotic challenge tests were also performed. The thawed samples were evaluated as fresh ones. The Pearson correlation between all parameters in fresh semen and all parameters in cryopreserved spermatozoa was assessed. Although some moderate correlations were found between the results of the osmotic tests and markers of sperm membrane stability (Yo-Pro 1 and Merocyanine 540) and post-thaw semen quality parameters, the predictive value of studied markers was rather weak - no cut-off values could be established and, based on regression models, they explained less than 40â¯% of variability in post-thaw quality. Our results confirm that cryodamage is a complex matter, in which many different factors play a role, affecting sperm motility and membrane integrity differently.
Subject(s)
Cell Membrane , Cryopreservation , Semen Analysis , Semen Preservation , Spermatozoa , Male , Animals , Cats/physiology , Spermatozoa/physiology , Cryopreservation/veterinary , Semen Analysis/veterinary , Semen Preservation/veterinary , Cell Membrane/physiology , Biomarkers , Osmotic Pressure/physiologyABSTRACT
PURPOSE: To compare the standard Yo-Yo intermittent recovery (IR) test and an agility Yo-Yo IR test with a higher number of change-of-direction movements to cardiorespiratory match performance. METHODS: The study included 11 professional male handball players (age 24.5 [4.6] y) of a German second-league team. The performance parameters of the players of the seasons 2016-17 to 2018-19 were analyzed. The Yo-Yo IR test was compared to a Yo-Yo IR test with multiple multidirectional changes of direction in response to visual stimuli, which was conducted on a SpeedCourt (Yo-Yo SC IR). Peak oxygen uptake (VO2peak) and maximum heart rate (HRmax) were measured. Between-methods differences of individual athletes were quantified with Bland-Altman plots. RESULTS: HRmax was not statistically different during the Yo-Yo SC IR test compared to the Yo-Yo IR test (181 [10] vs 188 [8] beats·min-1; P = .16). Agreement between the 2 tests was moderate for HRmax and good for heart rates >180 beats·min-1. Mean average VO2peak was 51.7 (3.9) and 50.9 (2.8) mL·min-1·kg-1 for the Yo-Yo SC IR test and the Yo-Yo IR test (P = .693), respectively. CONCLUSIONS: A Yo-Yo test with multidirectional changes of direction in response to visual stimuli yielded good agreement with the frequently used linear running tests and can be used to assess players' VO2peak. The HRmax achieved during this test should be used with caution.
Subject(s)
Athletic Performance , Exercise Test , Heart Rate , Oxygen Consumption , Physical Endurance , Humans , Male , Heart Rate/physiology , Oxygen Consumption/physiology , Athletic Performance/physiology , Young Adult , Physical Endurance/physiology , Exercise Test/methods , Adult , Sports/physiology , Cardiorespiratory Fitness/physiology , Competitive Behavior/physiologyABSTRACT
The structure collapse issues have long restricted the application of polycrystalline LiNixCoyMn1-x-yO2 (NCM) at high voltages beyond 4.4 V vs Li/Li+. Herein, for LiNi0.55Co0.12Mn0.33O2 (P-NCM), rapid surface degradation is observed upon the first charge, along with serious particle fragmentation upon repeated cycles. To alleviate these issues, a surface Co enrichment strategy is proposed [i.e., Co-enriched NCM (C-NCM)], which promotes the in situ formation of a robust surface rock-salt (RS) layer upon charge, serving as a highly stable interface for effective Li+ migration. Benefiting from this stabilized surface RS layer, Li+ extraction occurs mainly through this surface RS layer, rather than along the grain boundaries (GBs), thus reducing the risk of GBs' cracking and even particle fragmentation upon cycles. Besides, O loss and TM (TM = Ni, Co, and Mn) dissolution are also effectively reduced with fewer side reactions. The C-NCM/graphite cell presents a highly reversible capacity of 205.1 mA h g-1 at 0.2 C and a high capacity retention of 86% after 500 cycles at 1 C (1 C = 200 mA g-1), which is among the best reported cell performances. This work provides a different path for alleviating particle fragmentation of NCM cathodes.
ABSTRACT
Opsoclonus myoclonus syndrome (OMS) is a rare neurological disorder characterized by irregular, continuous, and chaotic eye saccades accompanied by myoclonus, defined by brief, shock-like muscle spasms in the arms or legs. This syndrome often presents with additional features such as cerebellar syndrome, nycthemeral rhythm disorders, hallucinosis, and irritability-type behavioral disorders. In adults, OMS is predominantly paraneoplastic, necessitating screening for onconeural antibodies (ONA). While specific medications for OMS are lacking, addressing the underlying cause may ameliorate its clinical manifestations. The presence of opsoclonus-myoclonus should prompt urgent and thorough investigation for an underlying cancer, given its frequent association with paraneoplastic neurological syndrome (PNS). Here, we present the case of a 39-year-old patient with opsoclonus associated with cerebellar ataxia, revealing a breast neoplasm with positive anti-YO antibodies. Through the review of the literature, we discuss the epidemiological, clinical, diagnostic, and therapeutic aspects of this rare situation.
ABSTRACT
Lifestyle interventions remain the treatment of choice for patients with obesity and metabolic complications, yet are difficult to maintain and often lead to cycles of weight loss and regain (weight cycling). Literature on weight cycling remains controversial and we therefore investigated the association between weight cycling and metabolic complications using preexistent obese mice. Ldlr-/-.Leiden mice received a high-fat diet (HFD) for 20 weeks to induce obesity. Subsequently, weight-cycled mice were switched between the healthy chow diet and HFD for four 2-week periods and compared to mice that received HFD for the total study period. Repeated weight cycling tended to decrease body weight and significantly reduced fat mass, whereas adipose tissue inflammation was similar relative to HFD controls. Weight cycling did not significantly affect blood glucose or plasma insulin levels yet significantly reduced plasma free fatty acid and alanine transaminase/aspartate transaminase levels. Hepatic macrovesicular steatosis was similar and microvesicular steatosis tended to be increased upon weight cycling. Weight cycling resulted in a robust decrease in hepatic inflammation compared to HFD controls while hepatic fibrosis and atherosclerosis development were not affected. These results argue against the postulate that repeated weight cycling leads to unfavorable metabolic effects, when compared to a continuous unhealthy lifestyle, and in fact revealed beneficial effects on hepatic inflammation, an important hallmark of non-alcoholic steatohepatitis.
Subject(s)
Liver , Non-alcoholic Fatty Liver Disease , Humans , Mice , Animals , Liver/metabolism , Mice, Obese , Weight Cycling , Non-alcoholic Fatty Liver Disease/etiology , Non-alcoholic Fatty Liver Disease/metabolism , Obesity/complications , Inflammation/metabolism , Diet, High-Fat/adverse effects , Mice, Inbred C57BLABSTRACT
We investigated the effects of far-infrared radiation (FIR) lamp therapy on changes in muscle damage and performance parameters following six sets of 15-min Loughborough intermittent shuttle test (LIST), a simulated soccer match. Twenty-four elite female soccer players (20-24 y) were assigned into FIR or sham treatment group (n = 12/group). The participants received a 60-min FIR or sham treatment (30 min per muscle) over knee extensors (KE) and flexors (KF) at 2, 25, 49, 73, and 97 h post-LIST. Maximal voluntary isometric contraction (MVC) torque and muscle soreness of the KE and KF, plasma creatine kinase (CK) activity as muscle damage markers, and several performance parameters including countermovement jump (CMJ) and Yo-Yo intermittent recovery test level 1 (YYIR1) were measured before and 1, 24, 48, 72, 96, and 120 h post-LIST. Changes in the measures were compared between groups by a mixed-design two-way ANOVA. The running distance covered during LIST and changes in the measures at 1-h post-LIST (before the treatment) were similar (p = 0.118-0.371) between groups. Changes in muscle damage markers at 24-120 h post-LIST were smaller (p < 0.05, η2 = 0.208-0.467) for the FIR (e.g., MVC-KE torque decrease at 48-h post-LIST: -1 ± 2%, peak KE soreness: 16 ± 10 mm, peak CK: 172 ± 42 IU/L) than sham group (-11 ± 9%, 33 ± 7 mm, 466 ± 220 IU/L, respectively). Performance parameters recovered faster (p < 0.05, η2 = 0.142-0.308) to baseline for the FIR (e.g., decreases at 48-h post-LIST; CMJ: 0 ± 1%, YYIR1: 0 ± 1%) than sham group (-6 ± 2%, -9 ± 6%, respectively). These results suggest that the FIR lamp therapy was effective for enhancing recovery from a soccer match.
Subject(s)
Athletic Performance , Soccer , Humans , Female , Soccer/physiology , Myalgia/radiotherapy , Knee/physiology , Knee Joint , Athletic Performance/physiologyABSTRACT
PURPOSE: In Football, the high-intensity running bouts during matches are considered decisive. Interestingly, recent studies showed that peak fat oxidation rates (PFO) are higher in football players than other athletes. This study aimed to investigate whether PFO increases following a pre-season. Secondarily, and due to COVID-19, we investigated whether PFO is related to the physical performance in a subgroup of semi-professional male football players. METHODS: Before and after 8 weeks of pre-season training, 42 sub-elite male football players (18 semi-professionals and 24 non-professionals) had a dual-energy x-ray absorptiometry scan and performed a graded exercise test on a treadmill for the determination of PFO, the exercise intensity eliciting PFO (Fatmax) and peak oxygen uptake (VÌO2peak). Additionally, the semi-professional players performed a Yo-Yo Intermittent Recovery Test level 2 (YYIR2) before and after pre-season training to determine football-specific running performance. RESULTS: PFO increased by 11 ± 10% (mean ± 95% CI), p = 0.031, and VÌO2peak increased by 5 ± 1%, p < 0.001, whereas Fatmax was unchanged (+12 ± 9%, p = 0.057), following pre-season training. PFO increments were not associated with increments in VÌO2peak (Pearson's r2 = 0.00, p = 0.948) or fat-free mass (FFM) (r2 = 0.00, p = 0.969). Concomitantly, YYIR2 performance increased in the semi-professional players by 39 ± 17%, p < 0.001, which was associated with changes in VÌO2peak (r2 = 0.35, p = 0.034) but not PFO (r2 = 0.13, p = 0.244). CONCLUSIONS: PFO, VÌO2peak, and FFM increased following pre-season training in sub-elite football players. However, in a subgroup of semi-professional players, increments in PFO were not associated with improvements in YYIR2 performance nor with increments in VÌO2peak and FFM.
Subject(s)
Athletic Performance , Running , Soccer , Humans , Male , Exercise Test , Oxygen , SeasonsABSTRACT
Connexin proteins are the building blocks of gap junctions and connexin hemichannels. Both provide a pathway for cellular communication. Gap junctions support intercellular communication mechanisms and regulate homeostasis. In contrast, open connexin hemichannels connect the intracellular compartment and the extracellular environment, and their activation fuels inflammation and cell death. The development of clinically applicable connexin hemichannel blockers for therapeutic purposes is therefore gaining momentum. This chapter describes a well-established protocol optimized for assessing connexin hemichannel activity by using the reporter dye Yo-Pro1.
Subject(s)
Connexin 43 , Connexins , Humans , Connexin 43/metabolism , Connexins/metabolism , Gap Junctions/metabolism , Cell Communication , Inflammation/metabolismABSTRACT
A 77-year-old female with a subacute progression of ataxia and serum anti-Yo antibodies was suspected to have paraneoplastic cerebellar degeneration (PCD). An examination of an underlying cancer showed no abnormality in the gynecological organs, but the findings did show a mass in the Douglas fossa. The mass was resected and diagnosed as stage IIB peritoneal serous papillary carcinoma (PSPC), a rare gynecologic cancer that is difficult to diagnose in the early stages. PCD was treated with intravenous immunoglobulin (IVIG). For an early diagnosis and treatment, PSPC should be included in the list of malignancies that cause PCD with anti-Yo antibodies.
ABSTRACT
This study examines the thermoluminescent (TL) properties of undoped Ca4YO(BO3)3 phosphor, focusing on how it behaves under a variety of experimental conditions. The IRSL-TL 565 nm was chosen as the appropriate detection filter among various optical detection filter combinations. During the preheating trials conducted at a rate of 2 °C/s, the TL peak exhibited increased intensity, particularly around 200 °C. The experimental outcomes demonstrated a reliable linear relationship (R2 = 0.996 and b = 1.015) in the dose response of undoped preheated Ca4YO(BO3)3 within the range of 1-200 Gy. The investigation encompasses a range of techniques, including the TM-Tstop method, computerized glow curve deconvolution (CGCD) analysis, and theoretical modelling. The application of the TM-Tstop method to samples irradiated with a 5 Gy dose revealed distinct zones on the TM versus Tstop diagram, signifying the presence of at least two discernible components within the TL glow curve, specifically, a single general order kinetics peak and a continuous distribution. The analysis of activation energy versus preheated temperature exhibited a stepwise curve, indicating five trap levels with depths ranging between 1.13 eV and 1.40 eV. The CGCD method also revealed the superposition of at least five distinct TL glow peaks. It was observed that their activation energies were consistent with the Tm-Tstop experiment. Furthermore, the low Figure of Merit (FOM) value of 1.18% indicates high reliability in the goodness-of-fit measure. These findings affirm the reliability and effectiveness of the employed methods in characterizing the TL properties of the Ca4YO(BO3)3 phosphor under investigation. Theoretical models, including the semi-localized transition model, were introduced to explain anomalous observations in TL glow peak intensities and heating rate patterns. While providing a conceptual framework, these models may require adjustments to accurately capture the specific characteristics uncovered through CGCD analysis. As a potential application, the study suggests that the characterized TL properties of Ca4YO(BO3)3 phosphor could be utilized in dosimetric applications, such as radiation dose measurements, owing to its reliable linear response within a broad dose range.
ABSTRACT
Gynecologic and breast malignancies are the cancers most commonly associated with paraneoplastic neurologic syndromes, of which the foremost is Yo [Purkinje cell antibody, type 1 (PCA-1)] paraneoplastic cerebellar degeneration. Yo syndrome affects women in the sixth decade and manifests as a subacute severe cerebellar ataxia. The association of the typical clinical picture with the detection of Yo antibodies in a patient's serum or CSF defines the diagnosis. Yo syndrome is always associated with a cancer, and the search for the underlying tumor should focus on ovarian and breast cancers and be repeated overtime if negative. The Yo autoantibodies are directed against the Yo antigens, aberrantly overexpressed by tumor cells with frequent somatic mutations and gene amplifications. The massive infiltration of these tumors by immune cells suggests that they are the site of the immune tolerance breakdown, leading to the destruction of Purkinje cells harboring the Yo antigens. Despite a growing understanding of the immunologic mechanisms, efficient therapeutic options are still lacking. Anti-Ri and antiamphiphysin syndromes are rarer and associated with breast cancers; a wide variety of other rare paraneoplastic neurologic syndromes have been described in association with gynecologic and breast malignancies that, though sharing some similarities, may have specific immune and genetics features leading to the immune tolerance breakdown.
Subject(s)
Breast Neoplasms , Paraneoplastic Cerebellar Degeneration , Female , Humans , Breast Neoplasms/complications , Paraneoplastic Cerebellar Degeneration/etiology , Paraneoplastic Cerebellar Degeneration/diagnosis , Autoantibodies , Purkinje Cells/pathologyABSTRACT
Weight cycling is a likely consequence of striving to lose weight after internalizing body image ideals, making upward social comparisons, and experiencing weight stigma. Despite weight cycling's potential physical and psychological consequences, the interplay of weight cycling, social pressures, and experienced and internalized stigma have not been qualitatively explored. Thus, through in-depth interviews of 36 weight-cycling adults, this study sought to understand how people negotiate weight cycling. Interviews informed the development of a qualitative model of weight cycling, which was derived from a theory-neutral inductive analysis. The model's stages included entering the cycle, undergoing the cycle, and challenging the cycle. Participants were triggered to enter the cycle due to weight stigma caused by social pressures. Within the cycle, interviewees internalized weight stigma and engaged in disordered weight management behaviors. Some participants challenged the cycle by becoming more self-aware and mitigating their toxic dieting behaviors. However, it was very difficult, if not impossible, for many to fully exit weight cycling and the restraints of previous weight management thinking and patterns. Our investigation underscores the seriousness of weight cycling and suggests ways to combat weight cycling on both macro and individual levels. It may also be useful to consider weight cycling as disordered eating in hopes of shifting society's dangerous focus on rapid weight loss.
Subject(s)
Body Image , Qualitative Research , Social Stigma , Humans , Female , Adult , Male , Body Image/psychology , Middle Aged , Interviews as Topic , Young Adult , Weight Loss , Self ConceptABSTRACT
Purkinje cell cytoplasmic autoantibody type 1 (PCA1), also known as anti-Yo, is a 'high-risk' paraneoplastic antibody, associated with rapidly progressive cerebellar syndrome. In patients with this syndrome, various MRI abnormalities have been documented, including atrophy in the cerebellum and brainstem, T2 hyperintensity in the brainstem and spinal cord, and cranial nerve enhancement. This report introduces an imaging finding, cerebellar leptomeningeal enhancement, which was observed in all three cases at early stages. Despite neurological deterioration, all patients underwent immunotherapy, and subsequent follow-up MRI revealed resolution of the leptomeningeal enhancement, suggesting that this feature is distinct from meningeal carcinomatosis.
Subject(s)
Cerebellar Diseases , Paraneoplastic Cerebellar Degeneration , Paraneoplastic Syndromes , Humans , Paraneoplastic Cerebellar Degeneration/diagnostic imaging , Paraneoplastic Cerebellar Degeneration/metabolism , Purkinje Cells/metabolism , Autoantibodies , Nerve Tissue Proteins , Cerebellum/metabolism , Cerebellar Diseases/diagnostic imaging , Cerebellar Diseases/metabolismABSTRACT
PURPOSE OF REVIEW: There is a common perception among the public that yo-yo dieting, defined as repeated cycles of weight loss followed by weight regain, results in accumulation of fat in the body and lower metabolic rate, thus hindering subsequent attempts to lose weight. We evaluated the effects of weight-cycling on body weight and body mass index (BMI), body composition including fat mass (FM) and lean body mass (LBM), and resting metabolic rate (RMR), by systematically reviewing existing scientific literature. RECENT FINDINGS: Twenty-three cross-sectional and cohort studies (including subjects with a history of weight-cycling compared to those without such history) and interventional studies (evaluating physiological effects during one or more cycles of weight loss and regain) were identified, conducted in generally healthy adults across various age groups, races, and both genders, who had normal weight, overweight, or obesity. Eighteen studies investigated the association between weight-cycling and body weight or BMI, and thirteen of them found no significant association. Fifteen out of twenty studies also found no increase in FM, and none of eighteen studies found a decrease in LBM. Twelve out of fourteen studies reported no adverse changes in RMR either. The overwhelming majority of evidence suggests that weight-cycling (yo-yo effect) is not associated with any adverse effects in body weight, body composition, and metabolic rate. Accordingly, healthy individuals who struggle with overweight or obesity should not be discouraged from repeated attempts to lose the excess weight.
Subject(s)
Obesity , Overweight , Adult , Female , Humans , Male , Cross-Sectional Studies , Obesity/metabolism , Weight Gain , Weight Loss/physiology , Body Mass Index , Body CompositionABSTRACT
Modeling paraneoplastic neurological diseases to understand the immune mechanisms leading to neuronal death is a major challenge given the rarity and terminal access of patients' autopsies. Here, we present a pilot study aiming at modeling paraneoplastic cerebellar degeneration with Yo autoantibodies (Yo-PCD). Female mice were implanted with an ovarian carcinoma cell line expressing CDR2 and CDR2L, the known antigens recognized by anti-Yo antibodies. To boost the immune response, we also immunized the mice by injecting antigens with diverse adjuvants and immune checkpoint inhibitors. Ataxia and gait instability were assessed in treated mice as well as autoantibody levels, Purkinje cell density, and immune infiltration in the cerebellum. We observed the production of anti-Yo antibodies in the CSF and serum of all immunized mice. Brain immunoreaction varied depending on the site of implantation of the tumor, with subcutaneous administration leading to a massive infiltration of immune cells in the meningeal spaces, choroid plexus, and cerebellar parenchyma. However, we did not observe massive Purkinje cell death nor any motor impairments in any of the experimental groups. Self-sustained neuro-inflammation might require a longer time to build up in our model. Unusual tumor antigen presentation and/or intrinsic, species-specific factors required for pro-inflammatory engagement in the brain may also constitute strong limitations to achieve massive recruitment of antigen-specific T-cells and killing of antigen-expressing neurons in this mouse model.
Subject(s)
Cerebellar Ataxia , Paraneoplastic Cerebellar Degeneration , Humans , Mice , Female , Animals , Pilot Projects , Cerebellum/pathology , Purkinje Cells/metabolism , Cerebellar Ataxia/pathology , AutoantibodiesABSTRACT
Resumo A psicologia do ego é reconhecida como uma releitura norte-americana da psicanálise, e teve Ernst Kris - que foi próximo de Freud - como um de seus fundadores. Apesar deste autor utilizar-se de textos freudianos para firmar os fundamentos de sua teoria, sustenta-se que a psicologia do ego mais se distancia do que se aproxima da obra de Freud. Este estudo visa demonstrar de que forma isso ocorre. Para isso, situa-se brevemente quem foi Ernst Kris e quais são as críticas já existentes à psicologia do ego. Num segundo momento, analisa-se o artigo "Ego Psychology and Interpretation in Psychoanalytic Therapy", de Kris, em confronto com a teoria de Freud. Por último, expõe-se a crítica de Lacan. Destaca-se que a crítica lacaniana remete a questões referentes à ética da psicanálise e ao lugar do analista na direção do tratamento.
Abstract Ego Psychology is a North-American re-reading of psychoanalysis and had Ernst Kris - a man who was close to Freud - as one of its founders. Despite using Freudian texts to establish its foundations, Ego Psychology distances itself from Freud's psychoanalysis. This study demonstrates how this occurs by briefly discussing who Ernst Kris was and the existing criticisms of Ego Psychology. Secondly, it analyzes Ernst Kris's article "Ego Psychology and Interpretation in Psychoanalytic Therapy" against Freud's theory, to finally present Lacan's critique, which refers to issues related to the ethics of psychoanalysis and the analyst's role in directing treatment.
Resumen La Psicología del Yo se considera como una relectura estadounidense del psicoanálisis y tuvo a Ernst Kris -quien era cercano a Freud- como uno de sus fundadores. A pesar de que Ernst Kris utiliza textos freudianos para establecer los fundamentos de su teoría, se sostiene que la Psicología del Yo se aleja más de la obra de Freud que se acerca a ella. Este estudio tiene como objetivo demostrar cómo ocurre esto. Para ello, se sitúa brevemente quién es Ernst Kris y cuáles son las críticas ya existentes a la Psicología del Yo. En segundo lugar, se analiza el artículo "Ego Psychology and interpretation in psychoanalytic therapy", de Ernst Kris, en confrontación con la teoría de Freud. Y, por último, se expone la crítica de Lacan. Se destaca que la crítica lacaniana remite a cuestiones relacionadas con la ética del psicoanálisis y el lugar del analista en la dirección del tratamiento.
Résumé La psychologie de l'égo est une relecture nord-américaine de la psychanalyse dont Ernst Kris, un homme proche de Freud, est l'un des fondateurs. Bien qu'elle utilise des textes freudiens pour établir ses fondements, la psychologie de l'égo s'éloigne de la pensée freudienne. Pour démontrer cet écart, cette étude aborde la figure de Ernst Kris et des critiques existantes à l'égard de la psychologie de l'égo. Ensuite, elle analyse l'article « Ego Psychology and interpretation in psychoanalytic therapy ¼ par rapport à la théorie de Freud, pour enfin présenter la critique de Lacan, qui se réfère à des questions liées à l'éthique de la psychanalyse et au rôle de l'analyste dans la direction du traitement.