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Nickel (Ni)-catalyzed growth of a single- or rotated-graphene layer is a well-established process above 800 K. In this report, a Au-catalyzed, low-temperature, and facile route at 500 K for graphene formation is described. The substantially lower temperature is enabled by the presence of a surface alloy of Au atoms embedded within Ni(111), which catalyzes the outward segregation of carbon atoms buried in the Ni bulk at temperatures as low as 400-450 K. The resulting surface-bound carbon in turn coalesces into graphene above 450-500 K. Control experiments on a Ni(111) surface show no evidence of carbon segregation or graphene formation at these temperatures. Graphene is identified by its out-of-plane optical phonon mode at 750 cm-1 and its longitudinal/transverse optical phonon modes at 1470 cm-1 while surface carbon is identified by its C-Ni stretch mode at 540 cm-1, as probed by high-resolution electron energy-loss spectroscopy. Dispersion measurements of the phonon modes confirm the presence of graphene. Graphene formation is observed to be maximum at 0.4 ML Au coverage. The results of these systematic molecular-level investigations open the door to graphene synthesis at the low temperatures required for integration with complementary metal-oxide-semiconductor processes.
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Exercise transiently impacts the expression, regulation, and activity of TERT/telomerase to maintain telomeres and protect the genome from insults. By protecting the telomeres (chromosome ends) and the genome, telomerase promotes cellular survival and prevents cellular senescence. By increasing cellular resiliency, via the actions of telomerase and TERT, exercise promotes healthy aging.
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Telomerase , Humanos , Telomerase/genética , Telomerase/metabolismo , Telômero/metabolismo , Senescência Celular/genéticaRESUMO
The parafascicular nucleus (Pf) in medial thalamus is interconnected with prefrontal cortex and basal ganglia. Though much research has determined its importance in cognitive regulation of behaviour, its projections to regions in subthalamus remain less known. Such connections include those to zona incerta (ZI), located immediately dorsal to subthalamic nuclei (STN) regulating motor output, and whose role in a motor context is only beginning to be investigated. We thus examined circuits from parafascicular (Pf) thalamus to ZI, and its activity during locomotion and spontaneous behaviours in mice. We found that a distinct group of CaMKIIα-positive excitatory parafascicular neurons, separated from VGLUT2-positive excitatory neurons, project widely into ZI, more than adjacent STN. Our results from fibre photometry and decoding with general linear model (GLM) indicate that PF-ZI pathways do not specifically correlate with amount of locomotion or movement velocity, but instead show more specified activity during relative directional changes of movements observed in turning, sniffing behaviours. These results hint at the PF-ZI pathway having a distinct role in directing action specificity and have implications for subcortical bases in dimensional control of behaviours.
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Núcleos Intralaminares do Tálamo/fisiologia , Atividade Motora/fisiologia , Vias Neurais/fisiologia , Zona Incerta/fisiologia , Animais , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Núcleo Subtalâmico/fisiologia , Proteína Vesicular 2 de Transporte de Glutamato/metabolismoRESUMO
A centrosome consists of a pair of centrioles and pericentriolar material (PCM). We manipulated expression of PCNT, a key PCM protein, and investigated roles of PCM in centriole behavior during mitosis. Deletion of PCNT had little effect on interphase centrosomes. However, centrioles in PCNT-deleted mitotic cells prematurely separated and frequently amplified, revealing that centrioles are limited within the spindle poles by PCNT during mitosis. It is known that specific cleavage of PCNT is necessary for centriole separation during mitotic exit. We observed delayed centriole separation in the G0 phase when a non-cleavable mutant form of PCNT was removed or when PCNT was artificially cleaved by TEV protease. Furthermore, a daughter centriole converts to a mother centriole only after experiencing both mitotic exit and specific PCNT cleavage. Based on these results, we propose that a centriole pair disengages upon entering mitosis but remains associated with the surrounding PCM proteins throughout mitosis. During mitotic exit, specific cleavage of PCNT induces PCM disintegration. As a result, a daughter centriole separates from the mother centriole and converts to a young mother centriole.
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Antígenos/metabolismo , Centríolos/metabolismo , Centrossomo/metabolismo , Mitose , Células HeLa , Humanos , Interfase , Proteínas Associadas aos Microtúbulos/metabolismoRESUMO
OBJECTIVE: Genetic variants of the cytoplasmic FMR1-interacting protein 2 (CYFIP2) encoding an actin-regulatory protein are associated with brain disorders, including intellectual disability and epilepsy. However, specific in vivo neuronal defects and potential treatments for CYFIP2-associated brain disorders remain largely unknown. Here, we characterized Cyfip2 heterozygous (Cyfip2+/- ) mice to understand their neurobehavioral phenotypes and the underlying pathological mechanisms. Furthermore, we examined a potential treatment for such phenotypes of the Cyfip2+/- mice and specified a neuronal function mediating its efficacy. METHODS: We performed behavioral analyses of Cyfip2+/- mice. We combined molecular, ultrastructural, and in vitro and in vivo electrophysiological analyses of Cyfip2+/- prefrontal neurons. We also selectively reduced CYFIP2 in the prefrontal cortex (PFC) of mice with virus injections. RESULTS: Adult Cyfip2+/- mice exhibited lithium-responsive abnormal behaviors. We found increased filamentous actin, enlarged dendritic spines, and enhanced excitatory synaptic transmission and excitability in the adult Cyfip2+/- PFC that was restricted to layer 5 (L5) neurons. Consistently, adult Cyfip2+/- mice showed increased seizure susceptibility and auditory steady-state responses from the cortical electroencephalographic recordings. Among the identified prefrontal defects, lithium selectively normalized the hyperexcitability of Cyfip2+/- L5 neurons. RNA sequencing revealed reduced expression of potassium channel genes in the adult Cyfip2+/- PFC. Virus-mediated reduction of CYFIP2 in the PFC was sufficient to induce L5 hyperexcitability and lithium-responsive abnormal behavior. INTERPRETATION: These results suggest that L5-specific prefrontal dysfunction, especially hyperexcitability, underlies both the pathophysiology and the lithium-mediated amelioration of neurobehavioral phenotypes in adult Cyfip2+/- mice, which can be implicated in CYFIP2-associated brain disorders. ANN NEUROL 2020;88:526-543.
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Proteínas Adaptadoras de Transdução de Sinal/genética , Compostos de Lítio/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/fisiopatologia , Convulsões/genética , Animais , Comportamento Animal/efeitos dos fármacos , Haploinsuficiência , Camundongos , Camundongos Mutantes , Neurônios/efeitos dos fármacos , Neurônios/patologia , Córtex Pré-Frontal/patologia , Convulsões/fisiopatologiaRESUMO
Porphyrin-derived molecules have received much attention for use in solar energy conversion devices, such as artificial leaves and dye-sensitized solar cells. Because of their technological importance, a molecular-level understanding of the mechanism for supramolecular structure formation in a liquid, as well as their stability under ultraviolet (UV) irradiation, is important. Here, we observed the self-assembled structure of free-base, copper(II), and nickel(II) octaethylporphyrin formed on Au(111) in a dodecane solution using scanning tunneling microscopy (STM). As evident in the STM images, the self-assembled monolayers (SAMs) of these three porphyrins on the Au(111) surface showed hexagonal close-packed structures when in dodecane solution. Under UV irradiation (λ = 365 nm), the porphyrin molecules in the SAM or the dodecane solution move extensively and form new porphyrin clusters on the Au sites that have a high degree of freedom. Consequently, the Au(111) surface was covered with disordered porphyrin clusters. However, we found that the porphyrin molecules decomposed under UV irradiation at 254 nm. Molecular-scale observation of the morphological evolution of the porphyrin SAM under UV irradiation can provide a fundamental understanding of the degradation processes of porphyrin-based energy conversion devices.
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Really interesting new gene (RING) finger protein 170 (RNF170) is an E3 ubiquitin ligase known to mediate ubiquitination-dependent degradation of type-I inositol 1,4,5-trisphosphate receptors (ITPR1). It has recently been demonstrated that a point mutation of RNF170 gene is linked with autosomal-dominant sensory ataxia (ADSA), which is characterized by an age-dependent increase of walking abnormalities, a rare genetic disorder reported in only two families. Although this mutant allele is known to be dominant, the functional identity thereof has not been clearly established. Here, we generated mice lacking Rnf170 (Rnf170(-/-)) to evaluate the effect of its loss of function in vivo. Remarkably, Rnf170(-/-) mice began to develop gait abnormalities in old age (12 months) in the form of asynchronous stepping between diagonal limb pairs with a fixed step sequence during locomotion, while age-matched wild-type mice showed stable gait patterns using several step sequence repertoires. As reported in ADSA patients, they also showed a reduced sensitivity for proprioception and thermal nociception. Protein blot analysis revealed that the amount of Itpr1 protein was significantly elevated in the cerebellum and spinal cord but intact in the cerebral cortex in Rnf170(-/-) mice. These results suggest that the loss of Rnf170 gene function mediates ADSA-associated phenotypes and this gives insights on the cure of patients with ADSA and other age-dependent walking abnormalities.
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Ataxia/congênito , Marcha/fisiologia , Ubiquitina-Proteína Ligases/genética , Fatores Etários , Animais , Ataxia/genética , Ataxia/fisiopatologia , Marcha/genética , Humanos , Camundongos , Camundongos Knockout , Ubiquitina-Proteína Ligases/deficiênciaRESUMO
Carbon monoxide (CO) is one of the most-studied molecules among the many modern industrial chemical reactions available. Following the Langmuir-Hinshelwood mechanism, CO conversion starts with adsorption on a catalyst surface, which is a crucially important stage in the kinetics of the catalytic reaction. Stepped surfaces show enhanced catalytic activity because they, by nature, have dense active sites. Recently, it was found that surface-sensitive adsorption of CO is strongly related to surface restructuring via roughening of a stepped surface. In this scanning tunneling microscopy study, we observed the thermal evolution of surface restructuring on a representative stepped platinum catalyst, Pt(557). CO adsorption at 1.4 mbar CO causes the formation of a broken-step morphology, as well as CO-induced triangular Pt clusters that exhibit a reversible disordered-ordered transition. Thermal instability of the CO-induced platinum clusters on the stepped surface was observed, which is associated with the reorganization of the repulsive CO-CO interactions at elevated temperature.
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This study describes a new effort toward understanding the interaction mechanisms between antibiotic-resistant Salmonella Typhimurium and phages. The antibiotic susceptibility, ß-lactamase activity, bacterial motility, gene expression, and lytic activity were evaluated in ciprofloxacin-induced antibiotic-sensitive Salmonella Typhimurium (ASST(CIP)) and ciprofloxacin-induced antibiotic-resistant S. Typhimurium (ARST(CIP)), which were compared to the wild-type strains (ASST(WT) and ARST(WT)). The MIC values of ampicillin, norfloxacin, chloramphenicol, and tetracycline were significantly increased to > 512, 16, 16, and 256 µg/ml, respectively, in the ARST(CIP). The lowest and highest extracellular lactamase activities were observed in ASST(WT) (6.85 µmol/min/ml) and ARST(CIP) (48.83 µmol/min/ml), respectively. The acrA, lpfE, and hilA genes were significantly upregulated by more than tenfold in both ASST(CIP) and ARST(CIP). The induction of multiple antibiotic resistance resulted from the increased efflux pump activity (AcrAB-TolC). The highest phage adsorption rates were more than 95 % for ASST(WT), ASST(CIP), and ARST(WT), while the lowest adsorption rate was 52 % for ARST(CIP) at 15 min of infection. The least lytic activity of phage was 20 % against the ARST(CIP), followed by ASST(CIP) (30 %). The adsorption rate of phage against ARST(CIP) was 52 % at 15 min of infection, which resulted in the decrease in lytic activity (12 %). Understanding the interaction of phage and bacteria is essential for the practical application of phage to control and detect antibiotic-resistant bacteria. The results provide useful information for understanding the binding specificity of phages for multiple antibiotic-resistant pathogens.
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Antibacterianos/farmacologia , Bacteriófagos/genética , Ciprofloxacina/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Ampicilina/farmacologia , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Sítios de Ligação , Cloranfenicol/farmacologia , Proteínas de Membrana Transportadoras/biossíntese , Proteínas de Membrana Transportadoras/genética , Testes de Sensibilidade Microbiana , Norfloxacino/farmacologia , Salmonella typhimurium/virologia , Tetraciclina/farmacologia , Transativadores/biossíntese , Transativadores/genética , beta-Lactamases/genéticaRESUMO
BACKGROUND: Bacteria treated with different classes of antibiotics exhibit changes in susceptibility to successive antibiotic treatments. This study was designed to evaluate the influence of sequential antibiotic treatments on the development of antibiotic resistance in Klebsiella pneumoniae associated with ß-lactamase and efflux pump activities. METHODS: The antibiotic susceptibility, ß-lactamase activity, and efflux activity were determined in K. pneumoniae grown at 37 °C by adding initial (0 h) and second antibiotics (8 or 12 h). Treatments include control (CON; no first and second antibiotic addition), no initial antibiotic addition followed by 1 MIC ciprofloxacin addition (CON-CIP), no initial antibiotic addition followed by 1 MIC meropenem addition (CON-MER), initial 1/4 MIC ciprofloxacin addition followed by no antibiotic addition (1/4CIP-CON), initial 1/4 MIC ciprofloxacin addition followed by 1 MIC ciprofloxacin addition (1/4CIP-CIP), and initial 1/4 MIC ciprofloxacin addition followed by 1 MIC meropenem addition (1/4CIP-MER). RESULTS: Compared to the CON, the initial addition of 1/4 MIC ciprofloxacin inhibited the growth of K. pneumoniae throughout the incubation period. The ciprofloxacin treatments (CON-CIP and 1/4CIP-CIP) showed significant reduction in the number of K. pneumoniae cells compared to meropenem (CON-MER and 1/4CIP-MER). The 1/4CIP-CIP achieved a further 1 log reduction of K. pneumoniae, when compared to the 1/4CIP-CON and 1/CIP-MER. The increase in sensitivity of K. pneumoniae to cefotaxime, kanamycin, levofloxacin, nalidixic acid was observed for CON-CIP. Noticeable cross-resistance pattern was observed at the 1/4CIP-CIP, showing the increased resistance of K. pneumoniae to chloramphenicol, ciprofloxacin, kanamycin, levofloxacin, nalidixic acid norfloxacin, sulphamethoxazole/trimethoprim, and tetracycline. The levels of ß-lactamase activities were estimated to be 8.4 µmol/min/ml for CON, 7.7 µmol/min/ml for 1/4CIP-CON and as low as 2.9 µmol/min/ml for CON-CIP. Compared to the absence of phenylalanine-arginine-ß-naphthylamide (PAßN), the fluorescence intensity of EtBr was increased in K. pneumoniae cells treated at the CON, CON-CIP, and CON-MER in the presence of PAßN. However, the efflux pump activity remained in K. pneumoniae cells treated at the 1/CIP, 1/CIP-CIP, and 1/CIP-MER in the presence of PAßN. CONCLUSION: The results suggest that the pre-exposed antibiotic history, treatment order, and concentrations influenced the development of multiple antibiotic resistant associated with ß-lactamase and efflux pump activities. This study highlights the importance of antibiotic treatment conditions, which would be taken into consideration when new antibiotic strategy is designed to prevent antibiotic resistance.
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Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Klebsiella pneumoniae/efeitos dos fármacos , Proteínas de Bactérias/metabolismo , Ciprofloxacina/farmacologia , Humanos , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/genética , Levofloxacino/farmacologia , Testes de Sensibilidade Microbiana , beta-Lactamases/metabolismoRESUMO
In vivo calcium imaging of neural activity is an indispensable approach for understanding the mechanisms and functions of neural system. Development of advanced imaging tools and various genetically encoded calcium indicators allows us to simultaneously record the activity of different neural populations. Here, we present a protocol for acquiring neural activity of two discrete neural populations in mice using dual-color fiber photometry. We describe steps for injecting viral constructs and implanting the fiber optic through stereotaxic surgery, calcium signal acquisition, and data analysis. We also describe the incorporation of electroencephalogram and electromyography recordings with dual-color fiber photometry analysis. For complete details on the use and execution of this protocol, please refer to Shin et al.1.
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Fotometria , Tálamo , Animais , Camundongos , Fotometria/métodos , Tálamo/diagnóstico por imagem , Tálamo/fisiologia , Cálcio/metabolismo , Eletroencefalografia/métodos , Eletromiografia/métodosRESUMO
Telomere shortening occurs with aging in immune cells and may be related to immunosenescence. Exercise can upregulate telomerase activity and attenuate telomere shortening in immune cells, but it is unknown if exercise impacts other immune tissues such as the thymus. This study aimed to examine human telomerase reverse transcriptase (hTERT) alternative splicing (AS) in response to aging and exercise in thymus tissue. Transgenic mice with a human TERT bacterial artificial chromosome integrated into its genome (hTERT-BAC) were utilized in two different exercise models. Mice of different ages were assigned to an exercise cage (running wheel) or not for 3 weeks prior to thymus tissue excision. Middle-aged mice (16 months) were exposed or not to treadmill running (30 min at 60% maximum speed) prior to thymus collection. hTERT transcript variants were measured by RT-PCR. hTERT transcripts decreased with aging (r = - 0.7511, p < 0.0001) and 3 weeks of wheel running did not counteract this reduction. The ratio of exons 7/8 containing hTERT to total hTERT transcripts increased with aging (r = 0.3669, p = 0.0423) but 3 weeks of voluntary wheel running attenuated this aging-driven effect (r = 0.2013, p = 0.4719). Aging increased the expression of senescence marker p16 with no impact of wheel running. Thymus regeneration transcription factor, Foxn1, went down with age with no impact of wheel running exercise. Acute treadmill exercise did not induce any significant changes in thymus hTERT expression or AS variant ratio (p > 0.05). In summary, thymic hTERT expression is reduced with aging. Exercise counteracted a shift in hTERT AS ratio with age. Our data demonstrate that aging impacts telomerase expression and that exercise impacts dysregulated splicing that occurs with aging.
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Animals must simultaneously select and balance multiple action contingencies in ambiguous situations: for instance, evading danger during feeding. This has rarely been examined in the context of information selection; despite corticothalamic pathways that mediate sensory attention being relatively well characterized, neural mechanisms filtering conflicting actions remain unclear. Here, we develop a new loom/feed test to observe conflict between naturally induced fear and feeding and identify a novel anterior cingulate cortex (ACC) output to the ventral anterior and ventral lateral thalamus (VA/VL) that adjusts selectivity between these innate actions. Using micro-endoscopy and fiber photometry, we reveal that activity in corticofugal outputs was lowered during unbalanced/singularly occupied periods, as were the resulting decreased thalamic initiation-related signals for less-favored actions, suggesting that the integration of ACC-thalamic firing may directly regulate the output of behavior choices. Accordingly, the optoinhibition of ACC-VA/VL circuits induced high bias toward feeding at the expense of defense. To identify upstream "commander" cortical cells gating this output, we established dual-order tracing (DOT)-translating ribosome affinity purification (TRAP)-a scheme to label upstream neurons with transcriptome analysis-and found a novel population of neurotensin-positive interneurons (ACCNts). The photoexcitation of ACCNts cells indeed caused similarly hyper-selective behaviors. Collectively, this new "corticofugal action filter" scheme suggests that communication in multi-step cingulate circuits may critically influence the summation of motor signals in thalamic outputs, regulating bias between innate action types.
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Giro do Cíngulo , Vias Neurais , Neurotensina , Animais , Giro do Cíngulo/metabolismo , Giro do Cíngulo/fisiologia , Camundongos , Masculino , Vias Neurais/fisiologia , Neurotensina/metabolismo , Tálamo/metabolismo , Tálamo/fisiologia , Camundongos Endogâmicos C57BL , Medo/fisiologia , Comportamento AlimentarRESUMO
Palladium catalysts are frequently employed in processes where methanol is an energy vector or carrier, being useful for the synthesis of methanol from mixtures of carbon dioxide and hydrogen (CO2/H2) or its steam reforming on demand. Results of synchrotron-based ambient pressure X-ray photoelectron spectroscopy for the adsorption of methanol on a Pd(111) model catalyst show a rich surface chemistry and complex phenomena that strongly depend on pressure and temperature. At low pressures (<10-6 Torr) and temperatures (<300 K), CO is the dominant decomposition product. As the pressure increases, cleavage of C-H, O-H, and C-O bonds is observed, and at elevated temperatures (400-600 K) the formation of CO and CHx/C fragments compete on the surface. Thus, existing reaction networks for methanol decomposition must be modified. Furthermore, surface and subsurface hydrogen (coming from PdHx) play a significant role in the stability and removal of CHx and C species.
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The adsorption properties of CO2 on the SrTiO3(001) surface were investigated using ambient pressure X-ray photoelectron spectroscopy under elevated pressure and temperature conditions. On the Nb-doped TiO2-enriched (1 × 1) SrTiO3 surface, CO2 adsorption, i.e., the formation of CO3 surface species, occurs first at the oxygen lattice site under 10-6 mbar CO2 at room temperature. The interaction of CO2 molecules with oxygen vacancies begins when the CO2 pressure increases to 0.25 mbar. The adsorbed CO3 species on the Nb-doped SrTiO3 surface increases continuously as the pressure increases but starts to leave the surface as the surface temperature increases, which occurs at approximately 373 K on the defect-free surface. On the undoped TiO2-enriched (1 × 1) SrTiO3 surface, CO2 adsorption also occurs first at the lattice oxygen sites. Both the doped and undoped SrTiO3 surfaces exhibit an enhancement of the CO3 species with the presence of oxygen vacancies, thus indicating the important role of oxygen vacancies in CO2 dissociation. When OH species are removed from the undoped SrTiO3 surface, the CO3 species begin to form under 10-6 mbar at 573 K, thus indicating the critical role of OH in preventing CO2 adsorption. The observed CO2 adsorption properties of the various SrTiO3 surfaces provide valuable information for designing SrTiO3-based CO2 catalysts.
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In consideration of the limited number of FDA-approved drugs for autism spectrum disorder (ASD), significant efforts have been devoted to identifying novel drug candidates. Among these, 5-HT7R modulators have garnered considerable attention due to their potential in alleviating autism-like behaviors in ASD animal models. In this study, we designed and synthesized biphenyl-3-ylmethylpyrrolidines 3 and biphenyl-3-yl-dihydroimidazoles 4 as 5-HT7R modulators. Through extensive biological tests of 3 and 4 in G protein and ß-arrestin signaling pathways of 5-HT7R, it was determined that 2-(2'-methoxy-[1,1'-biphenyl]-3-yl)-4,5-dihydro-1H-imidazole 4h acted as a 5-HT7R antagonist in both signaling pathways. In in vivo study with Shank3-/- transgenic (TG) mice, the self-grooming behavior test was performed with 4h, resulting in a significant reduction in the duration of self-grooming. In addition, an immunohistochemical experiment with 4h restored reduced neurogenesis in Shank3-/- TG mice, which is confirmed by the quantification of doublecortin (DCX) positive neurons, suggesting the promising therapeutic potential of 4h.
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Transtorno do Espectro Autista , Compostos de Bifenilo , Animais , Camundongos , Serotonina , beta-Arrestinas , Transdução de Sinais , Camundongos Transgênicos , Proteínas de Ligação ao GTP , Modelos Animais de Doenças , Proteínas dos Microfilamentos , Proteínas do Tecido NervosoRESUMO
Despite clinical data stretching over millennia, the neurobiological basis of the effectiveness of acupuncture in treating diseases of the central nervous system has remained elusive. Here, using an established model of acupuncture treatment in Parkinson's disease (PD) model mice, we show that peripheral acupuncture stimulation activates hypothalamic melanin-concentrating hormone (MCH) neurons via nerve conduction. We further identify two separate neural pathways originating from anatomically and electrophysiologically distinct MCH neuronal subpopulations, projecting to the substantia nigra and hippocampus, respectively. Through chemogenetic manipulation specifically targeting these MCH projections, their respective roles in mediating the acupuncture-induced motor recovery and memory improvements following PD onset are demonstrated, as well as the underlying mechanisms mediating recovery from dopaminergic neurodegeneration, reactive gliosis, and impaired hippocampal synaptic plasticity. Collectively, these MCH neurons constitute not only a circuit-based explanation for the therapeutic effectiveness of traditional acupuncture, but also a potential cellular target for treating both motor and non-motor PD symptoms.
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Auditory-induced arousal is a defense mechanism of animals against potential dangers. Although the thalamus is the neural substrate that relays sensory information to the cortex, its function is reduced during slow-wave sleep (SWS), also known as deep sleep. Despite this, animals are capable of waking up in response to external sensory stimuli, suggesting the existence of neural circuits that are involved in this response. Here, we report that kainate-class-type ionotropic glutamate receptor subunit 4 (GRIK4)-positive mediodorsal (MD) thalamic neurons act as a neural substrate for arousals from SWS. These neurons become active during arousal from SWS and their photoactivation can induce arousal from SWS. Moreover, we show that these neurons are influenced by glutamatergic neurons in the brainstem, the activity of which increases during auditory-induced arousals. These results suggest that this brainstem-MD pathway can mediate wakefulness from SWS.
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Sono de Ondas Lentas , Sono , Animais , Sono/fisiologia , Nível de Alerta/fisiologia , Tálamo/fisiologia , Vigília/fisiologia , Tronco EncefálicoRESUMO
Size- and shape-tailored copper (Cu) nanocrystals can offer vicinal planes for facile carbon dioxide (CO2) activation. Despite extensive reactivity benchmarks, a correlation between CO2 conversion and morphology structure has not yet been established at vicinal Cu interfaces. Herein, ambient pressure scanning tunneling microscopy reveals step-broken Cu nanocluster evolutions on the Cu(997) surface under 1 mbar CO2(g). The CO2 dissociation reaction produces carbon monoxide (CO) adsorbate and atomic oxygen (O) at Cu step-edges, inducing complicated restructuring of the Cu atoms to compensate for increased surface chemical potential energy at ambient pressure. The CO molecules bound at under-coordinated Cu atoms contribute to the reversible Cu clustering with the pressure gap effect, whereas the dissociated oxygen leads to irreversible Cu faceting geometries. Synchrotron-based ambient pressure X-ray photoelectron spectroscopy identifies the chemical binding energy changes in CO-Cu complexes, which proves the characterized real-space evidence for the step-broken Cu nanoclusters under CO(g) environments. Our in situ surface observations provide a more realistic insight into Cu nanocatalyst designs for efficient CO2 conversion to renewable energy sources during C1 chemical reactions.
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Soil contamination is associated with a high potential for health issues. This study aimed to investigate the bioaccumulation of heavy metals and its associated health impact among residents near a mining area. We performed environmental monitoring by analyzing lead (Pb), cadmium (Cd), and arsenic (As) levels in soil and rice samples, as well as biomonitoring by analyzing blood and urine samples from 58 residents living near the mine. Additionally, concentration trends were investigated among 26 participants in a 2013 study. The Cd and As levels in the soil samples and Cd levels in the rice samples exceeded the criteria for concern. The geometric mean blood Cd level (2.12 µg/L) was two times higher than that in the general population aged > 40 years. The blood Cd level showed decreasing trends from the previous measurements of 4.56-2.25 µg/L, but was still higher than that in the general population. The blood and urine Cd levels were higher in those with a low estimated glomerular filtration rate (eGFR) than in those with normal eGFR. In conclusion, heavy metals from mining areas can accumulate in soil and rice, adversely impacting human health. Continuous environmental monitoring and biomonitoring are required to ensure the safety of residents.