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High relapse rate during abstinence is a defining characteristic of drug addiction. We previously found that opioid seeking progressively increases after voluntary abstinence induced by adverse consequences of oxycodone seeking (crossing an electric barrier). Functional MRI revealed that this effect is associated with changes in functional connectivity within medial orbitofrontal cortex (mOFC)- and dorsomedial striatum (DMS)-related circuits. Here, we used a pharmacological manipulation and fMRI to determine the causal role of mOFC and DMS in oxycodone seeking after electric barrier-induced abstinence. We trained rats to self-administer oxycodone (6 h/day, 14 days). Next, we induced voluntary abstinence by exposing them to an electric barrier for 2 weeks. We inactivated the mOFC and DMS with muscimol+baclofen (GABAa and GABAb receptor agonists) and then tested them for relapse to oxycodone seeking on abstinence days 1 or 15 without the electric barrier or oxycodone. Inactivation of DMS (p < 0.001) but not mOFC decreased oxycodone seeking before or after electric barrier-induced abstinence. Functional MRI data revealed that DMS inactivation decreased cerebral blood volume levels in DMS and several distant cortical and subcortical regions (corrected p < 0.05). Furthermore, functional connectivity of DMS with several frontal, sensorimotor, and auditory regions significantly increased after DMS inactivation (corrected p < 0.05). Finally, an exploratory analysis of an existing functional MRI dataset showed that DMS inactivation restored voluntary abstinence-induced longitudinal changes in DMS functional connectivity with these brain regions (p < 0.05). Results indicate a role of DMS and related brain circuits in oxycodone seeking after voluntary abstinence, suggesting potential targets for intervention.
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Objective.The transcranial magnetic stimulation (TMS) coil induces an electric field that diminishes rapidly upon entering the brain. This presents a challenge in achieving focal stimulation of a deep brain structure. Neuronal elements, including axons, dendrites, and cell bodies, exhibit specific time constants. When exposed to repetitive TMS pulses at a high frequency, there is a cumulative effect on neuronal membrane potentials, resulting in temporal summation. This study aims to determine whether TMS pulse train at high-frequency and subthreshold intensity could induce a suprathreshold response.Approach.As a proof of concept, we developed a TMS machine in-house that could consistently output pulses up to 250 Hz, and performed experiments on 22 awake rats to test whether temporal summation was detectable under pulse trains at 100, 166, or 250 Hz.Main results.Results revealed that TMS pulses at 55% maximum stimulator output (MSO, peak dI/dt= 68.5 A/µs at 100% MSO, pulse width = 48µs) did not induce motor responses with either single pulses or pulse trains. Similarly, a single TMS pulse at 65% MSO failed to evoke a motor response in rats; however, a train of TMS pulses at frequencies of 166 and 250 Hz, but not at 100 Hz, successfully triggered motor responses and MEP signals, suggesting a temporal summation effect dependent on both pulse intensities and pulse train frequencies.Significance.We propose that the temporal summation effect can be leveraged to design the next-generation focal TMS system: by sequentially driving multiple coils at high-frequency and subthreshold intensity, areas with the most significant overlapping E-fields undergo maximal temporal summation effects, resulting in a suprathreshold response.
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Potencial Evocado Motor , Estimulação Magnética Transcraniana , Animais , Estimulação Magnética Transcraniana/métodos , Ratos , Masculino , Potencial Evocado Motor/fisiologia , Córtex Motor/fisiologia , Ratos Sprague-DawleyRESUMO
Importance: Identifying brain-based markers of resiliency that reliably predict who is and is not at elevated risk for developing psychopathology among children who experience adverse childhood experiences (ACEs) is important for improving our mechanistic understanding of these etiological links between child adversity and psychopathology and guiding precision medicine and prevention efforts for reducing psychiatric impact of ACEs. Objective: To examine associations between ACEs and transdiagnostic psychopathology during the transition from preadolescence to early adolescence and test whether these associations are moderated by a hypothesized resilience factor, a previously identified connectome variate (CV) that is associated with higher cognitive function and lower psychopathology. Design Setting and Participants: This study was conducted in a longitudinal design based on multicenter data from a community cohort of U.S. youth aged of 9-11 at baseline, who participated in the Adolescent Brain Cognitive Development (ABCD) study (N=7,382 at baseline and 6,813 at 2-year follow-up). Linear regression models and moderation analyses were used to characterize concurrent and prospective associations between lifetime ACEs and number of DSM-5 psychiatric disorders (indexing transdiagnostic psychopathology) and to determine if individual variations in these associations were moderated by the CV derived from resting-state fMRI at baseline. Main Outcomes and Measures: Cumulative number of current DSM-5 psychiatric disorders assessed using the computerized self-admin version Kiddie Schedule for Affective Disorders and Schizophrenia (KSADS-5) and lifetime ACEs assessed from child and parent reports at baseline (9-10 years) and 2-year-follow-up (11-12 years). Results: ACE total scores correlated positively with the cumulative number of current DSM-5 psychiatric disorders at both baseline (r =.258, p < .001) and 2-year follow-up (r =.257, p < .001). The baseline CV score moderated the ACE-disorder associations at baseline (B = -0.021, p < .001) and at 2-year follow-up (B = -0.018, p = .008), as well as the association between the changes in ACE and in the number of disorders from baseline to year 2 (B = -0.012, p = .045). Post-hoc analyses further showed that the moderation effect of CV on ACE-psychopathology associations was specific to the threat-related ACEs and to female youth. Conclusions and Relevance: These findings provide preliminary evidence for a connectome-based resiliency marker and suggest that functional connectivity strength in a broad system including frontal-parietal cortices and subcortical nuclei relevant to cognitive control may protect preadolescents who have experienced lifetime ACEs--especially females and those experiencing threat-related ACEs--from developing transdiagnostic psychopathology.
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Background: Modeling brain stimulation at the microscopic scale may reveal new paradigms for a variety of stimulation modalities. Objective: We present the largest map of distributions of the extracellular electric field to date within a layer L2/L3 mouse primary visual cortex brain sample, which was enabled by automated analysis of serial section electron microscopy images with improved handling of image defects (250×140×90 µm 3 volume). Methods: We used the map to identify microscopic perturbations of the extracellular electric field and their effect on the activating thresholds of individual neurons. Previous relevant studies modeled a macroscopically homogeneous cortical volume. Result: Our immediate result is a reduction of the predicted stimulation field strength necessary for neuronal activation by a factor of approximately 0.7 (or by 30%) on average, due to microscopic perturbations of the extracellular electric field-an electric field "spatial noise" with a mean value of zero. Conclusion: Although this result is largely sample-specific, it aligns with experimental data indicating that existing macroscopic theories substantially overestimate the electric fields necessary for brain stimulation. Significance statement: Currently, there is a discrepancy between macroscopic volumetric brain modeling for brain stimulation and experimental results: experiments typically reveal lower electric intensities required for brain stimulation. This study is arguably the first attempt to model brain stimulation at the microscopic scale, enabled by automated analysis of modern scanning electron microscopy images of the brain. The immediate result is a prediction of lower electric field intensities necessary for brain stimulation, with an average reduction factor of 0.7.
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BACKGROUND AND PURPOSE: Lung cancer surgery patients experience severe physical and mental symptoms, which seriously affect their quality of life and prognosis. Mindful breathing training is a promising strategy to improve their symptoms, but its effectiveness is affected by training compliance, and diary-based rehabilitation instruction has been shown to help improve training compliance. Therefore, the aim of this study was to evaluate the effects of mindful breathing training combined with diary-based rehabilitation guidance on improving perioperative outcomes in lung cancer surgery patients. MATERIALS AND METHODS: This single-center, assessor-blinded, prospective, three-arm randomized controlled trial was conducted from November 1, 2021 to November 1, 2022. Patients diagnosed with primary non-small cell lung cancer and scheduled for thoracoscopic surgery were randomly allocated to the combined intervention group, the mindful breathing group or the control group, with 34 patients in each group. The control group received routine care, while the mindful breathing group received mindful breathing training and routine care. The combined intervention group received both mindful breathing training and diary-based rehabilitation guidance, along with routine care. RESULTS: The per-protocol analysis revealed that patients in the mindful breathing group experienced statistically significant improvements in dyspnea, fatigue and anxiety. Patients in the combined intervention group had statistically significant improvements in dyspnea, fatigue, anxiety, depression, exercise self-efficacy and training compliance. CONCLUSION: This study provides evidence that mindful breathing training combined with diary-based rehabilitation guidance can be effective in improving perioperative outcomes in lung cancer patients. It can be applied in clinical practice in the future.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/cirurgia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Qualidade de Vida , Estudos Prospectivos , DispneiaRESUMO
AIM: To identify and appraise the quality of evidence of transitional care interventions on quality of life in lung cancer patients. BACKGROUND: Quality of life is a strong predictor of survival. The transition from hospital to home is a high-risk period for patients' readmission and death, which seriously affect their quality of life. DESIGN: Systematic review and meta-analysis. METHODS: The PubMed, Embase, Cochrane Library, Web of Science and CINAHL databases were searched from inception to 22 October 2022. The primary outcome was quality of life. Statistical analysis was conducted using Review Manager 5.4, results were expressed as standard mean difference (SMD) with a 95% confidence interval (CI). The risk of bias of the included studies was assessed using the Cochrane risk of bias assessment tool. This study was complied with PRISMA guidelines and previously registered in PROSPERO (CRD42023429464). RESULTS: Fourteen randomized controlled trials were included consisting of a total of 1700 participants, and 12 studies were included in the meta-analysis. It was found that transitional care interventions significantly improved quality of life (SMD = 0.21, 95% CI: 0.02 to 0.40, p = .03) and helped reduce symptoms (SMD = -0.65, 95% CI: -1.13 to -0.18, p = .007) in lung cancer patients, but did not significantly reduce anxiety and depression, and the effect on self-efficacy was unclear. CONCLUSIONS: This study shows that transitional care interventions can improve quality of life and reduce symptoms in patients, and that primarily educational interventions based on symptom management theory appeared to be more effective. But, there was no statistically significant effect on anxiety and depression. RELEVANCE TO CLINICAL PRACTICE: This study provides references for the application of transitional care interventions in the field of lung cancer care, and encourages nurses and physicians to apply transitional care plans to facilitate patients' safe transition from hospital to home. PATIENT OR PUBLIC CONTRIBUTION: No Patient or Public Contribution.
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Neoplasias Pulmonares , Qualidade de Vida , Cuidado Transicional , Humanos , Neoplasias Pulmonares/psicologia , Neoplasias Pulmonares/enfermagem , Neoplasias Pulmonares/terapia , Qualidade de Vida/psicologia , Cuidado Transicional/normasRESUMO
Objective. Transcranial magnetic stimulation (TMS) coil design involves a tradeoff among multiple parameters, including magnetic flux density (B), inductance (L), induced electric (E) field, focality, penetration depth, coil heating, etc. Magnetic materials with high permeability have been suggested to enhance coil efficiency. However, the introduction of magnetic core invariably increases coil inductance compared to its air-core counterpart, which in turn weakens theEfield. Our lab previously reported a rodent-specific TMS coil with silicon steel magnetic core, achieving 2 mm focality. This study aims to better understand the tradeoffs amongB,L,andEin the presence of magnetic core.Approach. The magnetic core initially operates within the linear range, transitioning to the nonlinear range when it begins to saturate at high current levels and reverts to the linear range as coil current approaches zero; both linear and nonlinear analyses were performed. Linear analysis assumes a weak current condition when magnetic core is not saturated; a monophasic TMS circuit was employed for this purpose. Nonlinear analysis assumes a strong current condition with varying degrees of core saturation.Main results. Results reveal that, the secondaryEfield generated by the silicon steel core substantially changed the dynamics during TMS pulse. Linear and nonlinear analyses revealed that higher inductance coils produced stronger peakEfields and longerEfield waveforms. On a macroscopic scale, the effects of these two factors on neuronal activation could be conceptually explained through a one-time-constant linear membrane model. Four coils with differentB,L,andEcharacteristics were designed and constructed. BothEfield mapping and experiments on awake rats confirmed that inductance could be much higher than previously anticipated, provided that magnetic material possesses a high saturation threshold.Significance. Our results highlight the novel potentials of magnetic core in TMS coil designs, especially for small animals.
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Silício , Estimulação Magnética Transcraniana , Ratos , Animais , Desenho de Equipamento , Estimulação Magnética Transcraniana/métodos , Roedores , Eletricidade , AçoRESUMO
BACKGROUND: Cognitive function and general psychopathology are two important classes of human behavior dimensions that are individually related to mental disorders across diagnostic categories. However, whether these two transdiagnostic dimensions are linked to common or distinct brain networks that convey resilience or risk for the development of psychiatric disorders remains unclear. METHODS: The current study is a longitudinal investigation with 11,875 youths from the Adolescent Brain Cognitive Development (ABCD) Study at ages 9 to 10 years at the onset of the study. A machine learning approach based on canonical correlation analysis was used to identify latent dimensional associations of the resting-state functional connectome with multidomain behavioral assessments including cognitive functions and psychopathological measures. For the latent resting-state functional connectivity factor showing a robust behavioral association, its ability to predict psychiatric disorders was assessed using 2-year follow-up data, and its genetic association was evaluated using twin data from the same cohort. RESULTS: A latent functional connectome pattern was identified that showed a strong and generalizable association with the multidomain behavioral assessments (5-fold cross-validation: ρ = 0.68-0.73 for the training set [n = 5096]; ρ = 0.56-0.58 for the test set [n = 1476]). This functional connectome pattern was highly heritable (h2 = 74.42%, 95% CI: 56.76%-85.42%), exhibited a dose-response relationship with the cumulative number of psychiatric disorders assessed concurrently and at 2 years post-magnetic resonance imaging scan, and predicted the transition of diagnosis across disorders over the 2-year follow-up period. CONCLUSIONS: These findings provide preliminary evidence for a transdiagnostic connectome-based measure that underlies individual differences in the development of psychiatric disorders during early adolescence.
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PROBLEM IDENTIFICATION: Systematic reviews in adults with cancer have shown the benefits of combined aerobic and resistance exercise (CE) interventions on physical and psychological fitness. However, data on the efficacy of CE interventions for children and adolescents are limited and discordant. LITERATURE SEARCH: The PubMed®, Embase®, Cochrane Central Register of Controlled Trials, Web of Science, and China National Knowledge Infrastructure electronic databases were searched from inception to April 19, 2022. DATA EVALUATION: Nine randomized controlled trials met the inclusion criteria. A quantitative synthesis method was used to investigate the effects of CE interventions on fatigue, cardiorespiratory fitness, physical activity levels, and health-related quality of life. SYNTHESIS: This systematic review and meta-analysis indicates that CE interventions have beneficial effects on the fatigue, cardiorespiratory fitness, and physical activity levels of this population. IMPLICATIONS FOR PRACTICE: Healthcare providers should implement CE interventions during hospital care and recommend home-based CE interventions to patients who have barriers to performing hospital-based sessions.
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Neoplasias , Qualidade de Vida , Adulto , Humanos , Adolescente , Criança , Neoplasias/terapia , China , Fadiga/terapia , Terapia por ExercícioRESUMO
Objective: This study aims to describe a MATLAB software package for transcranial magnetic stimulation (TMS) coil analysis and design. Approach: Electric and magnetic fields of the coils as well as their self- and mutual (for coil arrays) inductances are computed, with or without a magnetic core. Solid and stranded (Litz wire) conductors are also taken into consideration. The starting point is the centerline of a coil conductor(s), which is a 3D curve defined by the user. Then, a wire mesh and a computer aided design (CAD) mesh for the volume conductor of a given cross-section (circular, elliptical, or rectangular) are automatically generated. Self- and mutual inductances of the coil(s) are computed. Given the conductor current and its time derivative, electric and magnetic fields of the coil(s) are determined anywhere in space.Computations are performed with the fast multipole method (FMM), which is the most efficient way to evaluate the fields of many elementary current elements (current dipoles) comprising the current carrying conductor at a large number of observation points. This is the major underlying mathematical operation behind both inductance and field calculations. Main Results: The wire-based approach enables precise replication of even the most complex physical conductor geometries, while the FMM acceleration quickly evaluates large quantities of elementary current filaments. Agreement to within 0.74% was obtained between the inductances computed by the FMM method and ANSYS Maxwell 3D for the same coil model. Although not provided in this study, it is possible to evaluate non-linear magnetic cores in addition to the linear core exemplified. An experimental comparison was carried out against a physical MagVenture C-B60 coil; the measured and simulated inductances differed by only 1.25%, and nearly perfect correlation was found between the measured and computed E-field values at each observation point. Significance: The developed software package is applicable to any quasistatic inductor design, not necessarily to the TMS coils only.
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BACKGROUND: Cancer itself and surgery put a heavy burden on lung cancer patients, physiologically and psychologically. Enhancing self-efficacy during high-intensity interval training is essential for achieving the full benefit of pulmonary rehabilitation in lung cancer patients. OBJECTIVE: This study aimed to explore the effects of high-intensity interval training combined with team empowerment education on patients with lung resection. METHODS: This is a quasi-experimental trial with a pretest-posttest design. Participants were assigned to one of the 3 groups according to the order of admission: (1) combined intervention group, (2) intervention group, or (3) routine care group. The outcome measures included dyspnea, exercise capacity, exercise self-efficacy, anxiety, depression, postoperative indwelling time of thoracic drainage tube, and total in-hospital stay. RESULTS: Per-protocol results showed that dyspnea, exercise capacity, exercise self-efficacy, anxiety, and depression of the patients in the combined intervention group were significantly improved. However, no significant difference was observed in postoperative indwelling time of thoracic drainage tube or total in-hospital stay among the 3 groups. CONCLUSION: This hospital-based short-term high-intensity interval training combined with team empowerment education for lung cancer patients undergoing surgery was safe and feasible, indicating this program can be a promising strategy to manage perioperative symptoms. IMPLICATIONS FOR PRACTICE: This study provides evidence supporting preoperative high-intensity interval training as a promising method to make the best use of preoperative time, thus improving adverse symptoms in lung cancer patients undergoing surgery, and also provides a new strategy to raise exercise self-efficacy and promote patients' rehabilitation.
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Optogenetics is a widely used technology with potential for translational research. A critical component of such applications is the ability to track the location of the transduced opsin in vivo. To address this problem, we engineered an excitatory opsin, ChRERα (hChR2(134R)-V5-ERα-LBD), that could be visualized using positron emission tomography (PET) imaging in a noninvasive, longitudinal, and quantitative manner. ChRERα consists of the prototypical excitatory opsin channelrhodopsin-2 (ChR2) and the ligand-binding domain (LBD) of the human estrogen receptor α (ERα). ChRERα showed conserved ChR2 functionality and high affinity for [18F]16α-fluoroestradiol (FES), an FDA-approved PET radiopharmaceutical. Experiments in rats demonstrated that adeno-associated virus (AAV)-mediated expression of ChRERα enables neural circuit manipulation in vivo and that ChRERα expression could be monitored using FES-PET imaging. In vivo experiments in nonhuman primates (NHPs) confirmed that ChRERα expression could be monitored at the site of AAV injection in the primary motor cortex and in long-range neuronal terminals for up to 80 weeks. The anatomical connectivity map of the primary motor cortex identified by FES-PET imaging of ChRERα expression overlapped with a functional connectivity map identified using resting state fMRI in a separate cohort of NHPs. Overall, our results demonstrate that ChRERα expression can be mapped longitudinally in the mammalian brain using FES-PET imaging and can be used for neural circuit modulation in vivo.
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Neoplasias da Mama , Receptor alfa de Estrogênio , Ratos , Humanos , Animais , Feminino , Receptor alfa de Estrogênio/metabolismo , Opsinas/metabolismo , Tomografia por Emissão de Pósitrons , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Primatas , Estradiol/metabolismo , Neoplasias da Mama/metabolismo , Mamíferos/metabolismoRESUMO
AIM: To investigate the effectiveness of internet-based self-management interventions on pulmonary function in patients with chronic obstructive pulmonary disease (COPD). DESIGN: Systematic review and meta-analysis. DATA SOURCES: Eight electronic databases including PubMed, Web of Science, Cochrane library, Embase, CINAHL, China National Knowledge Infrastructure, Wangfang and Weipu databases were systematically searched from inception of the database to January 10, 2022. METHODS: Statistical analysis was performed using Review Manager 5.4 and results were reported as mean difference (MD) or standard mean difference (SMD) with 95% confidence intervals (CI). Outcomes were the forced expiratory volume in 1 second (FEV1), forced volume capacity (FVC) and percent of FEV1/FVC. The Cochrane Risk of Bias Tool was used to assess the risk of bias of included studies. The study protocol was not registered. RESULTS: Eight randomized controlled trials (RCTs) including 476 participants met the inclusion criteria and were included in meta-analysis. It was found that internet-based self-management interventions showed a significant improvement in FVC(L), while FEV1 (%), FEV1 (L), FEV1/FVC (%) and FVC (%) did not significantly improve. CONCLUSIONS: Internet-based self-management interventions were effective in improving pulmonary function in patients with COPD, caution should be exercised in interpreting the results. RCTs of higher quality are needed in the future to further demonstrate the effectiveness of the intervention. RELEVANCE TO CLINICAL PRACTICE: It provides evidence for internet-based self-management interventions in improving pulmonary function in patients with COPD. IMPACT: The results suggested that internet-based self-management interventions could improve the pulmonary function in people with COPD. This study provides a promising alternative method for patients with COPD who have difficulty seeking face-to-face self-management interventions, and the intervention can be applied in clinical settings. PATIENT OR PUBLIC CONTRIBUTION: No Patient or Public Contribution.
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Doença Pulmonar Obstrutiva Crônica , Autogestão , Humanos , China , Internet , Doença Pulmonar Obstrutiva Crônica/terapia , Qualidade de Vida , TelemedicinaRESUMO
BACKGROUND: Cancer itself and surgery pose a heavy burden on adults with lung cancer. Yoga breathing exercises have been proposed as a form of pulmonary rehabilitation exercises to improve these patients' perioperative outcomes. OBJECTIVE: To investigate the impact of yoga breathing exercises based on a problem-solving model on dyspnea, exercise capacity, anxiety, depression, and postoperative indwelling time of thoracic drainage tube and compliance in adults with lung cancer undergoing surgery. METHODS: One hundred eight lung cancer patients were randomly assigned to receive problem-solving model-based yoga breathing exercises, yoga breathing exercises, or usual care. Outcomes were collected at admission, the day before surgery, and at discharge. RESULTS: Patients in the combined intervention group showed a significantly greater improvement in dyspnea, exercise capacity, and anxiety compared with the control group. Yoga breathing training can significantly improve patients' dyspnea and anxiety. Significant difference favoring the combined group was observed in exercise capability and compliance between the 2 intervention groups. However, there was no significant difference in depression or indwelling time of thoracic drainage tube among the 3 groups at any time point. CONCLUSION: Findings indicate that yoga breathing exercises are effective in alleviating perioperative symptoms of lung resection patients. Compared with yoga breathing exercises, applying additional problem-solving model may achieve a better effect. IMPLICATIONS FOR PRACTICE: Yoga breathing exercises can be considered as a promising pulmonary rehabilitation strategy for lung cancer patients with surgery. The problem-solving model could be integrated into yoga breathing exercises in clinical practice to enhance the rehabilitation effect.
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Objective.Accurate modeling of transcranial magnetic stimulation (TMS) coils with the magnetic core is largely an open problem since commercial (quasi) magnetostatic solvers do not output specific field characteristics (e.g. induced electric field) and have difficulties when incorporating realistic head models. Many open-source TMS softwares do not include magnetic cores into consideration. This present study reports an algorithm for modeling TMS coils with a (nonlinear) magnetic core and validates the algorithm through comparison with finite-element method simulations and experiments.Approach.The algorithm uses the boundary element fast multipole method applied to all facets of a tetrahedral core mesh for a single-state solution and the successive substitution method for nonlinear convergence of the subsequent core states. The algorithm also outputs coil inductances, with or without magnetic cores. The coil-core combination is solved only once i.e. before incorporating the head model. The resulting primary TMS electric field is proportional to the total vector potential in the quasistatic approximation; it therefore also employs the precomputed core magnetization.Main results.The solver demonstrates excellent convergence for typical TMS field strengths and for analyticalB-Happroximations of experimental magnetization curves such as Froelich's equation or an arctangent equation. Typical execution times are 1-3 min on a common multicore workstation. For a simple test case of a cylindrical core within a one-turn coil, our solver computed the small-signal inductance nearly identical to that from ANSYS Maxwell. For a multiturn rodent TMS coil with a core, the modeled inductance matched the experimental measured value to within 5%.Significance.Incorporating magnetic core in TMS coil design has advantages of field shaping and energy efficiency. Our software package can facilitate model-informed design of more efficiency TMS systems and guide selection of core material. These models can also inform dosing with existing clinical TMS systems that use magnetic cores.
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Software , Estimulação Magnética Transcraniana , Estimulação Magnética Transcraniana/métodos , Análise de Elementos Finitos , Algoritmos , Fenômenos Magnéticos , Encéfalo/fisiologiaRESUMO
As a critical node connecting the forebrain with the midbrain, the lateral habenula (LHb) processes negative feedback in response to aversive events and plays an essential role in value-based decision-making. Compulsive drug use, a hallmark of substance use disorder, is attributed to maladaptive decision-making regarding aversive drug-use-related events and has been associated with dysregulation of various frontal-midbrain circuits. To understand the contributions of frontal-habenula-midbrain circuits in the development of drug dependence, we employed a rat model of methamphetamine self-administration (SA) in the presence of concomitant footshock, which has been proposed to model compulsive drug-taking in humans. In this longitudinal study, functional MRI data were collected at pretraining baseline, after 20 d of long-access SA phase, and after 5 d of concomitant footshock coupled with SA (punishment phase). Individual differences in response to punishment were quantified by a "compulsivity index (CI)," defined as drug infusions at the end of punishment phase, normalized by those at the end of SA phase. Functional connectivity of LHb with the frontal cortices and substantia nigra (SN) after the punishment phase was positively correlated with the CI in rats that maintained drug SA despite receiving increasing-intensity footshock. In contrast, functional connectivity of the same circuits was negatively correlated with CI in rats that significantly reduced SA. These findings suggest that individual differences in compulsive drug-taking are reflected by alterations within frontal-LHb-SN circuits after experiencing the negative consequences from SA, suggesting these circuits may serve as unique biomarkers and potential therapeutic targets for individualized treatment of addiction.
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Habenula , Metanfetamina , Transtornos Relacionados ao Uso de Substâncias , Humanos , Ratos , Animais , Habenula/fisiologia , Estudos Longitudinais , Comportamento Compulsivo , Lobo Frontal/diagnóstico por imagemRESUMO
Nicotine exposure is associated with regional changes in brain nicotinic acetylcholine receptors subtype expression patterns as a function of dose and age at the time of exposure. Moreover, nicotine dependence is associated with changes in brain circuit functional connectivity, but the relationship between such connectivity and concomitant regional distribution changes in nicotinic acetylcholine receptor subtypes following nicotine exposure is not understood. Although smoking typically begins in adolescence, developmental changes in brain circuits and nicotinic acetylcholine receptors following chronic nicotine exposure remain minimally investigated. Here, we combined in vitro nicotinic acetylcholine receptor autoradiography with resting state functional magnetic resonance imaging to measure changes in [3H]nicotine binding and α4ß2 subtype nicotinic acetylcholine receptor binding and circuit connectivity across the brain in adolescent (postnatal Day 33) and adult (postnatal Day 68) rats exposed to 6 weeks of nicotine administration (0, 1.2 and 4.8â mg/kg/day). Chronic nicotine exposure increased nicotinic acetylcholine receptor levels and induced discrete, developmental stage changes in regional nicotinic acetylcholine receptor subtype distribution. These effects were most pronounced in striatal, thalamic and cortical regions when nicotine was administered during adolescence but not in adults. Using these regional receptor changes as seeds, resting state functional magnetic resonance imaging identified dysregulations in cortico-striatal-thalamic-cortical circuits that were also dysregulated following adolescent nicotine exposure. Thus, nicotine-induced increases in cortical, striatal and thalamic nicotinic acetylcholine receptors during adolescence modifies processing and brain circuits within cortico-striatal-thalamic-cortical loops, which are known to be crucial for multisensory integration, action selection and motor output, and may alter the developmental trajectory of the adolescent brain. This unique multimodal study significantly advances our understanding of nicotine dependence and its effects on the adolescent brain.
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This meta-analysis was conducted to systematically evaluate the efficacy and safety of auricular acupressure on sleep quality in patients with lung cancer. Nine articles with a total of 802 patients were retrieved after searching on 11 electronic databases. Results of the meta-analysis showed that auricular acupressure improved sleep score (standard mean difference: -0.80, 95% confidence intervals: -1.30 to -0.30, P = .002) and reduced sleep disturbance rate (risk ratio: 0.65, 95% confidence intervals: 0.51-0.84, P = .001) and sleep medicine usage (risk ratio: 0.26, 95% confidence intervals: 0.11-0.65, P = .004) significantly. Our review suggests that auricular acupressure is effective and relatively safe in improving sleep quality among patients with lung cancer.
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Acupressão , Neoplasias Pulmonares , Transtornos do Sono-Vigília , Acupressão/métodos , Humanos , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/terapia , Qualidade do Sono , Transtornos do Sono-Vigília/etiologia , Transtornos do Sono-Vigília/terapiaRESUMO
BACKGROUND: Theta burst stimulation (TBS) is an efficient noninvasive neuromodulation paradigm that has been widely adopted, clinically. However, the efficacy of TBS treatment remains similarly modest as conventional 10 Hz repetitive transcranial magnetic stimulation (rTMS). OBJECTIVE/HYPOTHESIS: To develop a new TBS paradigm that enhances the effects of TMS administration while maintaining high time-efficiency. METHODS: We describe here a new TMS paradigm, named High-Density Theta Burst Stimulation (hdTBS). This paradigm delivers up to 6 pulses per burst, as opposed to only 3 in conventional TBS, while maintaining the inter-burst interval of 200 ms (or 5 Hz) - a critical parameter in inducing long-term potentiation. This paradigm was implemented on a TMS stimulator developed in-house; its physiological effects were assessed in the motor cortex of awake rats using a rodent specific focal TMS coil. Microwire electrodes were implanted into each rat's limb muscles to longitudinally record motor-evoked potential (MEP). Four different TBS paradigms (3, 4, 5 or 6 pulses per burst, 200 s per session) were tested; MEP signals were recorded immediately before (baseline) and up to 35 min post each TBS session. RESULTS: We developed a stimulator based on a printed-circuit board strategy. The stimulator was able to deliver stable outputs of up to 6 pulses per burst. Animal experiments (n = 15) revealed significantly different aftereffects induced by the four TBS paradigms (Friedman test, p = 0.018). Post hoc analysis further revealed that, in comparison to conventional 3-pulse TBS, 5- and 6-pulse TBS enhanced the aftereffects of MEP signals by 56% and 92%, respectively, while maintaining identical time efficiency. CONCLUSION(S): A new stimulation paradigm is proposed, implemented and tested in the motor cortex of awake rats using a focal TMS coil developed in the lab. We observed enhanced aftereffects as assessed by MEP, with no obvious adverse effects, suggesting the translational potentials of this paradigm.