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1.
Horm Behav ; 141: 105128, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35180615

RESUMO

Arginine-vasopressin (AVP) is a neurohypophyseal peptide that plays a critical role in the regulation of social behavior in mammals. Neuronal AVP regulates male-specific social signaling processes, such as exocrine urinary scent deposition and marking behavior in mice. In the periphery, AVP is transported to the portal bloodstream and acts as an antidiuretic hormone. These AVP dynamics imply that the central role of AVP in the stimulation of urinary marking is dissociated with the peripheral role of AVP in the retention of osmotic conditions. Using male BALB/c mice as subjects, peripheral injection of AVP decreased urinary marking and urination. In contrast, a central infusion of AVP facilitated urinary marking with no effect on urination, while an antagonist of the AVP 1a receptor inhibited marking. Centrally AVP-injected mice also exhibited typical behaviors, such as hiccough/sneeze-like reactions and flash scratching, particularly when confronted with a stimulus mouse through a wire mesh screen. Significant expression of these typical reactions in these mice resulted in the disruption of marking deposition. Further analysis of AVP synthesis illustrated that AVP levels increased in the midbrain but not in the circulation immediately after the test, particularly when confronted with a stimulus mouse. The central AVP regulates urinary marking and other typical behaviors in a dose- and situation-dependent manner. The sequential process implies that centrally synthesized AVP may be secreted into the circulation following immediate neuronal processes, and then peripheral AVP acts as an antidiuretic hormone on urinary marking behavior.


Assuntos
Arginina Vasopressina , Vasopressinas , Animais , Arginina , Arginina Vasopressina/metabolismo , Arginina Vasopressina/farmacologia , Humanos , Masculino , Mamíferos/metabolismo , Camundongos , Receptores de Vasopressinas/metabolismo , Comportamento Social , Vasopressinas/farmacologia
2.
Hum Mol Genet ; 26(19): 3797-3807, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28934393

RESUMO

Appropriate activation of the Ras/extracellular signal-regulated kinase (ERK) protein signaling cascade within the brain is crucial for optimal learning and memory. One key regulator of this cascade is the Nf1 Ras GTPase activating protein (RasGAP), which attenuates Ras/ERK signaling by converting active Ras is bound to guanosine triphosphate, activating Ras into inactive Ras is bound to guanosine diphosphate, inactivating Ras. A previous study using embryonic stem cells and embryonic stem cell-derived neurons indicated that Nf1 RasGAP activity is modulated by the highly regulated alternative splicing of Nf1 exon 23a. In this study, we generated Nf123aIN/23aIN mice, in which the splicing signals surrounding Nf1 exon 23a were manipulated to increase exon inclusion. Nf123aIN/23aIN mice are viable and exon 23a inclusion approaches 100% in all tissues, including the brain, where the exon is normally almost completely skipped. Ras activation and phosphorylation of ERK1/2 downstream of Ras are both greatly increased in Nf123aIN/23aIN mouse brain lysates, confirming that exon 23a inclusion inhibits Nf1 RasGAP activity in vivo as it does in cultured cells. Consistent with the finding of altered Ras/ERK signaling in the brain, Nf123aIN/23aIN mice showed specific deficits in learning and memory compared with Nf1+/+ mice. Nf123aIN/23aIN mice performed poorly on the T-maze and Morris water maze tests, which measure short- and long-term spatial memory, respectively. In addition, Nf123aIN/23aIN mice showed abnormally elevated context-dependent fear and a diminished ability to extinguish a cued fear response, indicating defective associative fear learning. Therefore, the regulated alternative splicing of Nf1 is an important mechanism for fine-tuning Ras/ERK signaling as well as learning and memory in mice.


Assuntos
Sistema de Sinalização das MAP Quinases , Neurofibromatose 1/genética , Proteínas ras/metabolismo , Processamento Alternativo , Animais , Células-Tronco Embrionárias/metabolismo , Éxons , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Aprendizagem , Camundongos , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Neurofibromatose 1/metabolismo , Neurofibromina 1/genética , Neurofibromina 1/metabolismo , Neurônios/metabolismo , Fosforilação , Transdução de Sinais
3.
J Neurosci ; 37(30): 7209-7218, 2017 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-28663199

RESUMO

The whisker system is an important sensory organ with extensive neural representations in the brain of the mouse. Patterned neural modules (barrelettes) in the ipsilateral principal sensory nucleus of the trigeminal nerve (PrV) correspond to the whiskers. Axons of the PrV barrelette neurons cross the midline and confer the whisker-related patterning to the contralateral ventroposteromedial nucleus of the thalamus, and subsequently to the cortex. In this way, specific neural modules called barreloids and barrels in the contralateral thalamus and cortex represent each whisker. Partial midline crossing of the PrV axons, in a conditional Robo3 mutant (Robo3R3-5cKO) mouse line, leads to the formation of bilateral whisker maps in the ventroposteromedial, as well as the barrel cortex. We used voltage-sensitive dye optical imaging and somatosensory and motor behavioral tests to characterize the consequences of bifacial maps in the thalamocortical system. Voltage-sensitive dye optical imaging verified functional, bilateral whisker representation in the barrel cortex and activation of distinct cortical loci following ipsilateral and contralateral stimulation of the specific whiskers. The mutant animals were comparable with the control animals in sensorimotor tests. However, they showed noticeable deficits in all of the whisker-dependent or -related tests, including Y-maze exploration, horizontal surface approach, bridge crossing, gap crossing, texture discrimination, floating in water, and whisking laterality. Our results indicate that bifacial maps along the thalamocortical system do not offer a functional advantage. Instead, they lead to impairments, possibly due to the smaller size of the whisker-related modules and interference between the ipsilateral and contralateral whisker representations in the same thalamus and cortex.SIGNIFICANCE STATEMENT The whisker sensory system plays a quintessentially important role in exploratory behavior of mice and other nocturnal rodents. Here, we studied a novel mutant mouse line, in which the projections from the brainstem to the thalamus are disrupted. This led to formation of bilateral whisker maps in both the thalamus and the cortex. The two whisker maps crowd in a space normally devoted to the contralateral map alone and in a nonoverlapping fashion. Stimulation of the whiskers on either side activates the corresponding region of the map. Mice with bilateral whisker maps perform well in general sensorimotor tasks but show poor performance in specific tests that require whisker-dependent tactile discrimination. These observations indicate that contralateral, instead of bilateral, representation of the sensory space plays a critical role in acuity and fine discrimination during somesthesis.


Assuntos
Comportamento Animal/fisiologia , Comportamento Exploratório/fisiologia , Rede Nervosa/fisiologia , Córtex Somatossensorial/fisiologia , Tato/fisiologia , Vibrissas/fisiologia , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Desempenho Psicomotor/fisiologia , Vibrissas/inervação
4.
Mol Ther ; 25(1): 127-139, 2017 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-28129109

RESUMO

Dominant missense mutations in TAR DNA-binding protein 43 (TDP-43) cause amyotrophic lateral sclerosis (ALS), and the cytoplasmic accumulation of TDP-43 represents a pathological hallmark in ALS and frontotemporal lobar degeneration (FTD). Behavioral investigation of the transgenic mouse model expressing the disease-causing human TDP-43 M337V mutant (TDP-43M337V mice) is encumbered by premature death in homozygous transgenic mice and a reported lack of phenotype assessed by tail elevation and footprint in hemizygous transgenic mice. Here, using a battery of motor-coordinative and cognitive tests, we report robust motor-coordinative and cognitive deficits in hemizygous TDP-43M337V mice by 8 months of age. After 12 months of age, cortical neurons are significantly affected by the mild expression of mutant TDP-43, characterized by cytoplasmic TDP-43 mislocalization, mitochondrial dysfunction, and neuronal loss. Compared with age-matched non-transgenic mice, TDP-43M337V mice demonstrate a similar expression of total TDP-43 but higher levels of TDP-43 in mitochondria. Interestingly, a TDP-43 mitochondrial localization inhibitory peptide abolishes cytoplasmic TDP-43 accumulation, restores mitochondrial function, prevents neuronal loss, and alleviates motor-coordinative and cognitive deficits in adult hemizygous TDP-43M337V mice. Thus, this study suggests hemizygous TDP-43M337V mice as a useful animal model to study TDP-43 toxicity and further consolidates mitochondrial TDP-43 as a novel therapeutic target for TDP-43-linked neurodegenerative diseases.


Assuntos
Disfunção Cognitiva/genética , Disfunção Cognitiva/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mutação , Desempenho Psicomotor , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Animais , Encéfalo/citologia , Encéfalo/metabolismo , Encéfalo/patologia , Locomoção , Camundongos , Camundongos Transgênicos , Atividade Motora , Força Muscular , Neurônios/metabolismo , Fragmentos de Peptídeos , Transporte Proteico
5.
J Neurosci ; 34(36): 12001-14, 2014 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-25186746

RESUMO

NMDARs play a major role in patterning of topographic sensory maps in the brain. Genetic knock-out of the essential subunit of NMDARs in excitatory cortical neurons prevents whisker-specific neural pattern formation in the barrel cortex. To determine the role of NMDARs en route to the cortex, we generated sensory thalamus-specific NR1 (Grin1)-null mice (ThNR1KO). A multipronged approach, using histology, electrophysiology, optical imaging, and behavioral testing revealed that, in these mice, whisker patterns develop in the trigeminal brainstem but do not develop in the somatosensory thalamus. Subsequently, there is no barrel formation in the neocortex yet a partial afferent patterning develops. Whisker stimulation evokes weak cortical activity and presynaptic neurotransmitter release probability is also affected. We found several behavioral deficits in tasks, ranging from sensorimotor to social and cognitive. Collectively, these results show that thalamic NMDARs play a critical role in the patterning of the somatosensory thalamic and cortical maps and their impairment may lead to pronounced behavioral defects.


Assuntos
Conectoma , Aprendizagem em Labirinto , Proteínas do Tecido Nervoso/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Córtex Somatossensorial/fisiologia , Tálamo/metabolismo , Percepção do Tato , Animais , Potenciais Evocados , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/genética , Receptores de N-Metil-D-Aspartato/genética , Comportamento Social , Córtex Somatossensorial/metabolismo , Tálamo/fisiologia , Núcleos do Trigêmeo/metabolismo , Núcleos do Trigêmeo/fisiologia , Vibrissas/inervação , Vibrissas/fisiologia
6.
Neuroendocrinology ; 100(2-3): 162-77, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25300872

RESUMO

Exposure to stressors such as foot shock (FS) leads to increased expression of multiple inflammatory factors, including the proinflammatory cytokine interleukin-1 (IL-1) in the brain. Studies have indicated that there are sex differences in stress reactivity, suggesting that the fluctuations in gonadal steroid levels across the estrous cycle may play a regulatory role in the stress-induced cytokine expression. The present studies were designed to investigate the role of 17-ß-estradiol (E2) and progesterone (Pg) in regulating the cytokine response within the paraventricular nucleus (PVN) of the hypothalamus through analysis of gene expression with real-time RT-PCR. Regularly cycling female rats showed a stress-induced increase in PVN IL-1 levels during the diestrous, proestrous, and estrous stages. During the metestrous stage, no change in IL-1 levels was seen following FS; however, estrogen receptor (ER)-ß levels did increase. Ovariectomy resulted in an increase in PVN IL-1 levels, which was attenuated by treatment with estradiol benzoate (10 or 50 µg), indicating an E2-mediated anti-inflammatory effect. Ovariectomized rats treated with Pg (500 or 1,250 µg) showed no alteration in IL-1 levels, but Pg did up-regulate ER-ß gene expression. The results from the current study implicate a potential mechanism through which high availability of endogenous Pg during the metestrous stage increases ER-ß sensitivity, which in turn attenuates the PVN IL-1 response to stress. Thus, the interaction between gonadal steroid hormones and their central receptors may exert a powerful inhibitory effect on neuroimmune consequences of stress throughout the estrous cycle.


Assuntos
Estradiol/metabolismo , Ciclo Estral/metabolismo , Interleucina-1/metabolismo , Núcleo Hipotalâmico Paraventricular/metabolismo , Progesterona/metabolismo , Estresse Psicológico/metabolismo , Animais , Modelos Animais de Doenças , Eletrochoque , Estradiol/análogos & derivados , Estradiol/farmacologia , Receptor beta de Estrogênio/metabolismo , Feminino , Neuroimunomodulação/efeitos dos fármacos , Neuroimunomodulação/fisiologia , Ovariectomia , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Progesterona/administração & dosagem , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Substâncias para o Controle da Reprodução/farmacologia
7.
J Med Imaging Radiat Sci ; 55(3): 101412, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38679515

RESUMO

INTRODUCTION: Simulation-based education has been particularly valuable as a preclinical training method that adequately prepares students for clinical practice, including simulation in educational programs enhances the quality of learning outcomes. However, relevant previous research has exhibited several crucial limitations, with most of them having focused solely on the setup procedures. This study aimed to outline the development of an educational application in radiationtherapy and emphasizes the essential factors that radiation therapist technologists(RTTs) must consider in the treatment room from the perspective of experienced RTTs. METHOD: We connected the virtual pendants to the linear accelerator components using C# programming and Unity. Customized scripts were assigned to specific linear accelerator (LINAC) functions, and the patient and RTT avatars were developed. We also included audio feedback for the realistic gantry movement sounds. RESULT: This study outlines various aspects of radiotherapy procedures duringtreatment, such as the simulation of patient positioning, treatment fields, and pendantfunctions, aimed toward enabling the effective use of virtual reality technology inradiation therapy. DISCUSSION: This study explores the potential of an avatar-based app for radiotherapy education, providing foundational data for future trials. CONCLUSION: Simulation learning is the most advantageous pre-clinical instrument for equipping students with the skills necessary for clinical practice. This study's resultsare expected to facilitate radiotherapy students' adoption of clinical replacement applications and improve collaborative partnerships and knowledge sharing. Notably, this application complements traditional learning methods, further enhancing the overall educational experience.

8.
Radiol Phys Technol ; 17(1): 288-296, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38316688

RESUMO

Previous radiation protection-measure studies for medical staff who perform X-ray fluoroscopy have employed simulations to investigate the use of protective plates and their shielding effectiveness. Incorporating directional information enables users to gain a clearer understanding of how to position protective plates effectively. Therefore, in this study, we propose the visualization of the directional vectors of scattered rays. X-ray fluoroscopy was performed; the particle and heavy-ion transport code system was used in Monte Carlo simulations to reproduce the behavior of scattered rays in an X-ray room by reproducing a C-arm X-ray fluoroscopy system. Using the calculated results of the scattered-ray behavior, the vectors of photons scattered from the phantom were visualized in three dimensions. A model of the physician was placed on the directional vectors and dose distribution maps to confirm the direction of the scattered rays toward the physician when the protective plate was in place. Simulation accuracy was confirmed by measuring the ambient dose equivalent and comparing the measured and calculated values (agreed within 10%). The directional vectors of the scattered rays radiated outward from the phantom, confirming a large amount of backscatter radiation. The use of a protective plate between the patient and the physician's head part increased the shielding effect, thereby enhancing radiation protection for the physicians compared to cases without the protective plate. The use of directional vectors and the surrounding dose-equivalent distribution of this method can elucidate the appropriate use of radiation protection plates.


Assuntos
Exposição Ocupacional , Proteção Radiológica , Humanos , Espalhamento de Radiação , Proteção Radiológica/métodos , Simulação por Computador , Raios X , Fluoroscopia , Imagens de Fantasmas , Doses de Radiação , Exposição Ocupacional/prevenção & controle
9.
Radiat Prot Dosimetry ; 200(8): 779-790, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38767288

RESUMO

Photon energy is higher than the (γ,n) threshold, allowing it to interact with the nuclei of materials with high z properties and liberate fast neutrons. This represents a potentially harmful source of radiation for humans and the environment. This study validated the Monte Carlo simulation, using the particle and heavy-ion transport code system (PHITS) on a TrueBeam 10-MV linear particle accelerator's head shielding model and then used this PHITS code to simulate a photo-neutron spectrum for the transport of the beam. The results showed that, when comparing the simulated to measured PDD and crosslines, 100% of the γ-indexes were <1 (γ3%/3mm) for both simulations, for both phase-space data source and a mono energy source. Neutron spectra were recorded in all parts of the TrueBeam's head, as well as photon neutron spectra at three points on the beamline.


Assuntos
Simulação por Computador , Método de Monte Carlo , Nêutrons , Aceleradores de Partículas , Fótons , Aceleradores de Partículas/instrumentação , Humanos , Proteção Radiológica/métodos , Íons Pesados , Doses de Radiação , Cabeça/efeitos da radiação , Radiometria/métodos
10.
Peptides ; 175: 171178, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38368908

RESUMO

Engaging in positive social (i.e., prosocial) interactions during adolescence acts to modulate neural circuits that determine adult adaptive behavior. While accumulating evidence indicates that a strong craving for prosocial behavior contributes to sustaining neural development, the consequences of social deprivation during adolescence on social neural circuits, including those involving oxytocin (OXT) and vasopressin (AVP), are poorly characterized. We evaluated adaptive behaviors in socially isolated mice, including anxiety-like, social, and defensive behaviors, along with OXT and AVP neural profiles in relevant brain regions. Social isolation from postnatal day (P-)22 to P-48 induced enhanced defensive and exploratory behaviors, in nonsocial and social contexts. Unlike OXT neurons, AVP+ cell density in the paraventricular nucleus of the hypothalamus increases with age in males. Social isolation also modulated gene expression in the medial amygdala (MeA), including the upregulation of OXT receptors in males and the downregulation of AVP1a receptors in both sexes. Socially isolated mice showed an enhanced defensive, anogenital approach toward a novel adult female during direct social interactions. Subsequent c-Fos mapping revealed diminished neural activity in restricted brain areas, including the MeA, lateral septum, and posterior intralaminar nucleus of the thalamus, in socially isolated mice. These data indicate that neural signals arising from daily social interactions invoke region-specific modification of neuropeptide expression that coordinates with altered defensiveness and neural responsivities, including OXT- and AVP-projecting regions. The present findings indicate an involvement of OXT and AVP circuits in adolescent neural and behavioral plasticity that is tuned by daily social interaction.


Assuntos
Hipotálamo , Ocitocina , Masculino , Camundongos , Feminino , Animais , Hipotálamo/metabolismo , Ocitocina/metabolismo , Receptores de Ocitocina/genética , Receptores de Ocitocina/metabolismo , Isolamento Social , Tonsila do Cerebelo/metabolismo , Comportamento Social , Arginina Vasopressina/metabolismo
11.
Chem Senses ; 38(5): 391-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23564012

RESUMO

Rodents rely on olfactory stimuli to communicate information between conspecifics that is critical for health and survival. For example, rodents that detect a food odor simultaneously with the social odor carbon disulfide (CS(2)) will acquire a preference for that food. Disruption of the chemosensory transduction cascade in CS(2-)sensitive olfactory sensory neurons (OSNs) that express the receptor guanylyl cyclase type D (GC-D; GC-D+ OSNs) will prevent mice from acquiring these preferences. GC-D+ OSNs also respond to the natriuretic peptide uroguanylin, which is excreted into urine and feces. We analyzed if uroguanylin could also act as a social stimulus to promote the acquisition of food preferences. We found that feces of mice that had eaten odored food, but not unodored food, promoted a strong preference for that food in mice exposed to the feces. Olfactory exploration of uroguanylin presented with a food odor similarly produced a preference that was absent when mice were exposed to the food odor alone. Finally, the acquisition of this preference was dependent on GC-D+ OSNs, as mice lacking GC-D (Gucy2d(-)(/-) mice) showed no preference for the demonstrated food. Together with our previous findings, these results demonstrate that the diverse activators of GC-D+ OSNs elicit a common behavioral result and suggest that this specialized olfactory subsystem acts as a labeled line for a type of associative olfactory learning.


Assuntos
Preferências Alimentares/efeitos dos fármacos , Guanilato Ciclase/metabolismo , Peptídeos Natriuréticos/farmacologia , Neurônios Receptores Olfatórios/efeitos dos fármacos , Receptores de Superfície Celular/metabolismo , Animais , Guanilato Ciclase/deficiência , Ligantes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios Receptores Olfatórios/enzimologia , Neurônios Receptores Olfatórios/metabolismo , Receptores de Superfície Celular/deficiência
12.
Physiol Behav ; 272: 114373, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37805136

RESUMO

The three-chamber test, the so-called sociability test, has been widely used to assess social deficits based on impaired socially oriented investigations in rodent models. An innate motivation for investigating conspecifics is theoretically a prerequisite for gaining sociability scores in this paradigm. However, several relevant factors mediating investigatory motives, such as familiarity, attractiveness, and aggression, may affect sociability scores, which must be verified to obtain an adequate evaluation of the psychiatric phenotypes exhibited by disease-relevant rodent models. We assessed the social and non-social factors that mediate proximity preference by the three-chamber test with standard C57BL/6 J (B6) mice and low sociability BTBR+ltpr3tf/J (BTBR) mice. Strains of the opponents had no effect. Sexual cues (i.e., opposite sex) increased proximity preference in both strains of mice; in contrast, novel objects induced an approach in B6 mice but avoidance in BTBR mice. Single-housing before testing, stimulated social motive, affected BTBR mice but not B6 mice. BTBR females showed increased proximity preference across the sessions, and BTBR males showed increased preference toward a male B6 stimulus, but not a male BTBR stimulus. The male preference was restored when the male BTBR stimulus was anesthetized. In addition, self-grooming was facilitated by social and non-social novelty cues in both strains. B6 mice predominantly exhibited an investigatory approach toward social or non-social stimuli, whereas BTBR mice recognized social cues but tended to show avoidance. The three-chamber test could evaluate approach-avoidance strategies in target mouse strains that comprise innate social distance between mice.


Assuntos
Agressão , Comportamento Social , Feminino , Camundongos , Masculino , Animais , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Camundongos Endogâmicos
13.
Curr Res Neurobiol ; 5: 100102, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37638344

RESUMO

Brain serotonin (5-hydroxytryptamine, 5-HT) is a key molecule for the mediation of depression-related brain states, but the neural mechanisms underlying 5-HT mediation need further investigation. A possible mechanism of the therapeutic antidepressant effects is neurogenic cell production, as stimulated by 5-HT signaling. Neurogenesis, the proliferation of neural stem cells (NSCs), and cell differentiation and maturation occur across brain regions, particularly the hippocampal dentate gyrus and the subventricular zone, throughout one's lifespan. 5-HT plays a major role in the mediation of neurogenic processes, which in turn leads to the therapeutic effect on depression-related states. In this review article, we aim to identify how the neuronal 5-HT system mediates the process of neurogenesis, including cell proliferation, cell-type differentiation and maturation. First, we will provide an overview of the neurogenic cell transformation that occurs in brain regions containing or lacking NSCs. Second, we will review brain region-specific mechanisms of 5-HT-mediated neurogenesis by comparing regions localized to NSCs, i.e., the hippocampus and subventricular zone, with those not containing NSCs. Highlighting these 5-HT mechanisms that mediate neurogenic cell production processes in a brain-region-specific manner would provide unique insights into the role of 5-HT in neurogenesis and its associated effects on depression.

14.
Res Sq ; 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36909537

RESUMO

Oxytocin (OXT) a neuropeptide synthesized in the hypothalamic nuclei has a variety of function including socio-emotional processes in mammals. While the neural circuits and signaling pathways in central OXT converge in the paraventricular nucleus of the hypothalamus (PVN), we illuminate specific function of discrete PVN OXT circuits, which connect to the medial amygdala (MeA) and the bed nucleus of the stria terminalis (BnST) in mouse models. The OXTPVN→BnST projections are innervated from entire portions of the PVN, while those OXTPVN→MeA projections are asymmetrically innervated from the posterior portion of the PVN. Compared with OXT neurons in B6 wild type mice, BTBR mice that are recognized as a behavior-based autism model exhibited defect in the OXTPVN→BnST projection. We demonstrate that chemogenetic activation of OXTPVN→MeA circuit enhances anxiety-like behavior and facilitates social approach behavior, while activation of OXTPVN→BnST circuit suppresses anxiety-like behavior along with inhibiting social approach. This chemogenetic manipulation on the OXTPVN→BnST circuit proves ineffective in BTBR mice. Accordingly, chemogenetic activation of OXTPVN neurons that stimulate both OXT circuits induces OXT receptor expressions in both MeA and BnST as with those by social encounter in B6 mice. The induction of OXT receptor genes in the BnST was not observed in BTBR mice. These data support the hypothesis that OXT circuits serve as a regulator for OXT signaling in PVN to control socio-emotional approach/avoidance behavior, and a defect of OXTPVN→BnST circuit contributes to autism-like social phenotypes in BTBR mice.

15.
Radiol Phys Technol ; 16(2): 203-211, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36877400

RESUMO

The use of cone-beam computed tomography (CBCT) is expanding owing to its installation in linear accelerators for radiation therapy, and the imaging dose induced by this system has become the center of attention. Here, the dose to patients caused by the CBCT imager was investigated. Organ doses and effective doses for male and female mesh-type reference computational phantoms (MRCPs) and pelvis CBCT mode, routinely used for pelvic irradiation, were estimated using the Particle and Heavy Ion Transport Code System. The simulation results were confirmed based on the point-dose measurements. The estimated organ doses for male MRCPs with/without raised arms and for female MRCPs with/without raised arms were 0.00286-35.6 mGy, 0.00286-35.1 mGy, 0.00933-39.5 mGy, and 0.00931-39.0 mGy, respectively. The anticipated effective doses for male MRCPs with/without raised arms and female MRCPs with/without raised arms irradiated by pelvis CBCT mode were 4.25 mSv, 4.16 mSv, 7.66 mSv, and 7.48 mSv, respectively. The results of this study will be useful for patients who undergo image-guided radiotherapy with CBCT. However, because this study only covered one type of cancer with one type of imager, and image quality was not considered, more studies should be conducted to estimate the radiation dose from imaging devices in radiation therapy.


Assuntos
Neoplasias Pélvicas , Radioterapia Guiada por Imagem , Humanos , Masculino , Adulto , Feminino , Radioterapia Guiada por Imagem/métodos , Neoplasias Pélvicas/diagnóstico por imagem , Neoplasias Pélvicas/radioterapia , Dosagem Radioterapêutica , Simulação por Computador , Imagens de Fantasmas , Tomografia Computadorizada de Feixe Cônico/métodos , Método de Monte Carlo , Doses de Radiação
16.
Psychoneuroendocrinology ; 149: 106004, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36543023

RESUMO

BTBR T+ Itpr3tf/J (BTBR) mice display several behavioral characteristics, including social deficits resembling the core symptoms of human autism. Atypical social behaviors include sequential processes of assembled cognitive-behavior components, such as recognition, investigatory assessment, and signaling response. This study aimed to elucidate the neural circuits responsible for the regulation of the social signaling response, as shown by scent marking behavior in male mice. We first assessed the recognition and investigatory patterns of male BTBR mice compared to those of C57BL/6 J (B6) mice. Next, we examined their scent-marking behavior as innate social signaling responses adjusted to a confronted feature of social stimuli and situations, along with the expression of c-Fos as a marker of neuronal activity in selected brain areas involved in the regulation of social behavior. The function of the targeted brain area was confirmed by chemogenetic manipulation. We also examined the social peptides, oxytocin and vasopressin neurons of the major brain regions that are associated with the regulation of social behavior. Our data indicate that male BTBR mice are less responsive to the presentation of social stimuli and the expression of social signaling responses, which is paralleled by blunted c-Fos responsivity and vasopressin neurons morphological changes in selected brain areas, including the posterior bed nucleus of the stria terminalis (pBnST) and lateral habenula (LHb) in BTBR mice. Further investigation of LHb function revealed that chemogenetic inhibition and activation of LHb activity can induce a change in scent marking responses in both B6 and BTBR mice. Our elucidation of the downstream LHb circuits controlling scent marking behavior indicates intact function in BTBR mice. The altered morphological characteristics of oxytocin neurons in the paraventricular nucleus of the hypothalamus and vasopressin-positive neurons and axonal projections in the pBnST and LHb appear to underlie the dysfunction of scent marking responses in BTBR mice. (300/300 words).


Assuntos
Transtorno Autístico , Habenula , Núcleos Septais , Humanos , Camundongos , Masculino , Animais , Transtorno Autístico/metabolismo , Ocitocina , Núcleos Septais/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Comportamento Social , Modelos Animais de Doenças
17.
Neuropharmacology ; 237: 109634, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37301467

RESUMO

The inbred mouse strain, BTBR T+Itpr3tf/J (BTBR), possesses neuronal and circuit abnormalities that underlie atypical behavioral profiles resembling the major symptoms of human autism spectrum disorder (ASD). Forebrain serotonin (5-HT) transmission has been implicated in ASD-related behavioral alterations. In this study, we assessed 5-HT signals and the functional responsiveness in BTBR mice compared to standard C57BL/6J (B6) control mice to elucidate how 5-HT alterations contribute to behavioral abnormalities in BTBR mice. A lower number of 5-HT neurons in the median raphe, but not in the dorsal raphe, was observed in male and female BTBR mice. Acute systemic injection of buspirone, a 5-HT1A receptor agonist, induced c-Fos in several brain regions in both B6 and BTBR mice; however, blunted c-Fos induction in BTBR mice was documented in the cingulate cortex, basolateral amygdala (BLA), and ventral hippocampus (Hipp). Decreased c-Fos responses in these regions are associated with a lack of buspirone effects on anxiety-like behavior in BTBR mice. Analysis of mRNA expression following acute buspirone injection indicated that 5HTR1a gene downregulation (or upregulation) occurred in the BLA and Hipp of B6 mice, respectively, but not BTBR mice. The mRNA expression of factors associated with neurogenesis or the pro-inflammatory state was not consistently altered by acute buspirone injection. Therefore, 5-HT responsivity via 5-HT1A receptors in the BLA and Hipp are linked to anxiety-like behavior, in which circuits are disrupted in BTBR mice. Other distinct 5-HT circuits from the BLA and Hipp that regulate social behavior are restricted but preserved in BTBR mice.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Humanos , Camundongos , Masculino , Feminino , Animais , Transtorno Autístico/metabolismo , Transtorno do Espectro Autista/metabolismo , Buspirona , Serotonina , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Comportamento Social , Modelos Animais de Doenças , Fenótipo , RNA Mensageiro/metabolismo
18.
Phys Med ; 116: 103181, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38000101

RESUMO

PURPOSE: In this study, we aimed to establish a method for predicting the probability of each acute radiation dermatitis (ARD) grade during the head and neck Volumetric Modulated Arc Therapy (VMAT) radiotherapy planning phase based on Bayesian probability. METHODS: The skin dose volume >50 Gy (V50), calculated using the treatment planning system, was used as a factor related to skin toxicity. The empirical distribution of each ARD grade relative to V50 was obtained from the ARD grades of 119 patients (55, 50, and 14 patients with G1, G2, and G3, respectively) determined by head and neck cancer specialists. Using Bayes' theorem, the Bayesian probabilities of G1, G2, and G3 for each value of V50 were calculated with an empirical distribution. Conversely, V50 was obtained based on the Bayesian probabilities of G1, G2, and G3. RESULTS: The empirical distribution for each graded patient group demonstrated a normal distribution. The method predicted ARD grades with 92.4 % accuracy and provided a V50 value for each grade. For example, using the graph, we could predict that V50 should be ≤24.5 cm3 to achieve G1 with 70 % probability. CONCLUSIONS: The Bayesian probability-based ARD prediction method could predict the ARD grade at the treatment planning stage using limited patient diagnostic data that demonstrated a normal distribution. If the probability of an ARD grade is high, skin care can be initiated in advance. Furthermore, the V50 value during treatment planning can provide radiation oncologists with data for strategies to reduce ARD.


Assuntos
Neoplasias de Cabeça e Pescoço , Radiodermite , Radioterapia de Intensidade Modulada , Humanos , Teorema de Bayes , Neoplasias de Cabeça e Pescoço/radioterapia , Radiodermite/tratamento farmacológico , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos , Probabilidade , Planejamento da Radioterapia Assistida por Computador/métodos , Dosagem Radioterapêutica
19.
Brain Behav Immun ; 26(1): 40-9, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21798342

RESUMO

Odorant cues released by rodents play a key role in mate preference/selection. The goal of the following series of studies was to determine the impact of acute illness, and the potential role of the inflammatory response, on the release of illness-associated odor cues from female rats. Adult female Sprague-Dawley rats were injected with lipopolysaccharide (LPS, 100 µg/kg) and their soiled bedding was used as a stimulus to naïve male odor recipients. While odored bedding from sick males elicited a robust avoidance response evidenced by decreased sniffing, avoidance and burying behavior, odored bedding from sick females elicited only a reduction in sniffing, indicating a reduction in odor attractiveness. Odor cues from ovariectomized, but not sham-operated females decreased sniffing behavior and increased avoidance in male odor recipients. Acute estradiol benzoate (EB, 20 µg/kg) replacement into ovariectomized females restored the investigatory response of male recipients toward odor cues, while LPS administration into ovariectomized oil or EB treated females had little impact on odor attractiveness. Measurement of cytokines in both brain (the paraventricular nucleus of the hypothalamus) and blood from female odor donors indicated increased expression of TNF-α, IL-1ß, and IL-6 following LPS, which was not affected by EB treatment. These findings illustrate a critical sexual dimorphism by demonstrating that acute illness reduces the attractiveness of female odor, whereas odor cues from sick males are highly aversive. Moreover, the attractiveness of female odor appears to be associated with circulating ovarian hormone levels, but not central or peripheral inflammatory cytokines.


Assuntos
Sinais (Psicologia) , Citocinas/fisiologia , Doença/psicologia , Estrogênios/fisiologia , Odorantes , Comportamento Social , Animais , Encéfalo/patologia , Estradiol/análogos & derivados , Estradiol/farmacologia , Estrogênios/farmacologia , Ciclo Estral/fisiologia , Comportamento Exploratório/fisiologia , Feminino , Hormônios/sangue , Imunidade/fisiologia , Lipopolissacarídeos/farmacologia , Masculino , Ovariectomia , Núcleo Hipotalâmico Paraventricular/fisiologia , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Caracteres Sexuais , Olfato/fisiologia
20.
Neurosci Biobehav Rev ; 136: 104597, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35248677

RESUMO

Arginine vasopressin (AVP) is a neurohypophysial hormone that coordinatively regulates central socio-emotional behavior and peripheral control of antidiuretic fluid homeostasis. Most mammals, including rodents, utilize exocrine or urine-contained scent marking as a social signaling tool that facilitates social adaptation. The exocrine scent marking behavior is postulated to fine-tune sensory and cognitive abilities to recognize key social features via exocrine/urinary olfactory cues and subsequently control exocrine deposition or urinary marking through the mediation of osmotic fluid balance. AVP is implicated as a major player in controlling both recognition and signaling responses. This review provides constructive hypotheses on the coordinative processes of the AVP neurohypophysial circuits in the systemic regulations of fluid control and social-communicative behavior, via the expression of exocrine scent marking, and further emphasizes a potential role of AVP in a common mechanism underlying social communication in rodents.


Assuntos
Arginina Vasopressina , Odorantes , Animais , Humanos , Mamíferos , Olfato , Comportamento Social
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