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1.
Molecules ; 29(2)2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38257266

RESUMO

The innovative synthesis of 3,8-dibromo-2,9-dinitro-5,6-dihydrodiimidazo [1,2-a:2',1'-c]pyrazine and 3,9-dibromo-2,10-dinitro-6,7-dihydro-5H-diimidazo [1,2-a:2',1'-c][1,4]diazepine is described in this study. The tricyclic fused molecular structures are formed by the respective amalgamation of piperazine and homopiperazine with the imidazole ring containing nitro. Compound 1 and 2 possess excellent high-density physical properties (ρ1 = 2.49 g/cm3, ρ2 = 2.35 g/cm3) due to the presence of a fused ring structure and Br atom. In addition to their high density, they have high decomposition temperatures (Td > 290 °C) which means that they have excellent thermal stability and can be used as potential heat-resistant explosives. Low mechanical sensitivities (IS > 40 J, FS > 360 N) are observed. The twinning structure of 2 was resolved by X-ray diffraction. Non-covalent interaction analysis, Hirshfeld surfaces, 2D fingerprint plot, and Electrostatic potential analysis were used to understand the intramolecular interactions in relation to physicochemical properties. The unique structures of this type of compound provide new potential for the evolution of energetic materials.

2.
J Neurosci ; 42(16): 3394-3405, 2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-35241493

RESUMO

Feedforward and feedback pathways interact in specific dendritic domains to enable cognitive functions such as predictive processing and learning. Based on axonal projections, hierarchically lower areas are thought to form synapses primarily on dendrites in middle cortical layers, whereas higher-order areas are thought to target dendrites in layer 1 and in deep layers. However, the extent to which functional synapses form in regions of axodendritic overlap has not been extensively studied. Here, we use viral tracing in the secondary visual cortex of male mice to map brain-wide inputs to thick-tufted layer 5 pyramidal neurons. Furthermore, we provide a comprehensive map of input locations through subcellular optogenetic circuit mapping. We show that input pathways target distinct dendritic domains with far greater specificity than appears from their axonal branching, often deviating substantially from the canonical patterns. Common assumptions regarding the dendrite-level interaction of feedforward and feedback inputs may thus need revisiting.SIGNIFICANCE STATEMENT Perception and learning depend on the ability of the brain to shape neuronal representations across all processing stages. Long-range connections across different hierarchical levels enable diverse sources of contextual information, such as predictions or motivational state, to modify feedforward signals. Assumptions regarding the organization of this hierarchical connectivity have not been extensively verified. Here, we assess the synaptic connectivity of brain-wide projections onto pyramidal neurons in the visual cortex of mice. Using trans-synaptic viral tracing and subcellular optogenetic circuit mapping, we show that functional synapses do not follow the consistent connectivity rule predicted by their axonal branching patterns. These findings highlight the diversity of computational strategies operating throughout cortical networks and may aid in building better artificial networks.


Assuntos
Neurônios , Córtex Visual , Animais , Axônios/fisiologia , Dendritos/fisiologia , Retroalimentação , Masculino , Camundongos , Neurônios/fisiologia , Sinapses/fisiologia , Córtex Visual/fisiologia
3.
Angew Chem Int Ed Engl ; 62(40): e202310320, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37582683

RESUMO

Axially chiral N-substituted quinazolinones are important bioactive molecules, which are presented in many synthetic drugs. However, most strategies toward their atroposelective synthesis are mainly limited to the axially chiral arylquinazolinone frameworks. The development of modular synthetic methods to access diverse quinazolinone-based atropisomers remains scarce and challenging. Herein, we report the regio- and atroposelective synthesis of axially chiral N-vinylquinazolinones via the strategy of asymmetric allylic substitution-isomerization. The catalysis system utilized both asymmetric transition-metal catalysis and organocatalysis to efficiently afford trisubstituted and tetrasubstituted N-vinylquinazolinone atropisomers, respectively. With the meticulous design of ß-substituted allylic substrates, both Z- and E-tetrasubstituted axially chiral N-vinylquinazolinones were obtained in good yields and high enantioselectivities.

4.
Anal Bioanal Chem ; 414(19): 5917-5928, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35723722

RESUMO

Flexible sensing is an alternative to traditional sensing and possesses good flexibility and wearability. Intrinsically conductive polymers, particularly poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS), have received significant attention due to their high mechanical flexibility and good biocompatibility. Here, we report the design of highly conductive and electrochemically active PEDOT:PSS-coated plastic substrate electrodes by combining N-doped graphene (NG) or S-doped graphene (SG) with methanesulfonic acid-treated PEDOT:PSS (denoted as NG-f-MSA-PEDOT:PSS/PET and SG-f-MSA-PEDOT:PSS/PET) by a simple drop-coating method. At room temperature, the NG-f-MSA-PEDOT:PSS/PET electrode demonstrated the lowest detection limits of 17.09, 33.84, 28.30, and 44.96 nM for paracetamol, uric acid, dopamine, and catechol (S/N = 3), respectively. The NG-f-MSA-PEDOT:PSS/PET electrode had good anti-interference ability and reproducibility without employing expensive noble metals and requiring much effort to polish the surface of traditional glass carbon electrodes. Most importantly, this film electrode could maintain a stable electrochemical response under different bending and crease states and had excellent mechanical stability and flexibility.


Assuntos
Dopamina , Grafite , Acetaminofen , Compostos Bicíclicos Heterocíclicos com Pontes , Plásticos , Reprodutibilidade dos Testes , Ácido Úrico
5.
Angew Chem Int Ed Engl ; 61(51): e202210456, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36281992

RESUMO

Axially chiral molecules bearing multiple stereogenic axes are of great importance in the field of organic chemistry. However, the efficient construction of atropisomers featuring two different types of stereogenic axes has rarely been explored. Herein, we report the novel atroposelective synthesis of configurationally stable axially chiral B,N-heterocycles. By using stepwise asymmetric allylic substitution-isomerization (AASI) strategy, diaxially chiral B,N-heterocycles bearing B-C and C-N axes that are related to the moieties of axially chiral enamines and arylborons were also obtained. In this case, all four stereoisomers of diaxially chiral B,N-heterocycles were stereodivergently afforded in high enantioselectivities. Density functional theory (DFT) studies demonstrated that the NH⋅⋅⋅π interactions played a unique role in the promotion of stereospecific isomerization, thereby leading to the highly efficient central-to-axial chirality transfer.

6.
Bioorg Med Chem ; 28(13): 115574, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32546302

RESUMO

Free fatty acid receptor 1 (FFA1 or GPR40) has been studied for many years as a target for the treatment of type 2 diabetes mellitus. In order to increase potency and reduce hepatotoxicity, a series of novel compounds containing imidazo[1,2-a]pyridine scaffold as GPR40 agonist were synthesized. Compound I-14 was identified as an effective agonist as shown by the conspicuous drop in blood glucose in normal and diabetic mice. It had no risk of hepatotoxicity compared with TAK-875. Moreover, good pharmacokinetic (PK) properties of I-14 were observed (CL = 27.26 ml/h/kg, t1/2 = 5.93 h). The results indicate that I-14 could serve as a possible candidate to treat diabetes.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/síntese química , Piridinas/síntese química , Receptores Acoplados a Proteínas G/agonistas , Animais , Benzofuranos/farmacologia , Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Avaliação Pré-Clínica de Medicamentos , Teste de Tolerância a Glucose , Humanos , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/farmacocinética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fenilpropionatos/química , Piridinas/efeitos adversos , Piridinas/farmacocinética , Ratos Sprague-Dawley , Sulfonas/farmacologia
7.
J Mater Sci Mater Med ; 29(11): 162, 2018 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-30357538

RESUMO

There is an increasing clinical need to design dental restorative materials that combine excellent mechanical property and anti-biofilm activity. In the current study, photocurable polycation functionalized nanodiamond (QND) was synthesized and proposed as novel filler for dental resins. By reason of increased repulsive force between nanoparticles and enhanced compatibility with resin matrix, QND dispersed uniformly in reinforced resins, which would help to transfer stress and deformation from the matrix to fillers more efficiently, resulting in a significant improvement in mechanical properties. Notably, the Vickers's hardness, flexural strength and flexural modulus of resins containing 1.0 wt% QND were 44.5, 36.1 and 41.3% higher than that of control, respectively. The antibacterial activity against Streptococcus mutans (S. mutans) showed that QND-incorporated resins produced anti-adhesive property due to their hydrophilic surfaces and could suppress bacterial growth as a result of the contact-killing effect of embedded nanocomposites. As the synergistic effect of anti-adhesive and bactericidal performance, resins loading 1.0~1.5 wt% QNDs displayed excellent anti-biofilm activity. Meanwhile, the results of macrophage cytotoxicity showed that the proliferation of RAW 264.7 cells remained 84.3%, even at a concentration of 1.0 wt% QNDs after 7-day incubation. Therefore, the QND-containing dental resin with the combination of high mechanical property, bacteria-repellent capability and antibacterial performance holds great potential as a restorative material based on this scheme.


Assuntos
Biofilmes/efeitos dos fármacos , Materiais Dentários , Nanodiamantes/química , Polímeros/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Mecânica , Camundongos , Células RAW 264.7 , Streptococcus mutans/efeitos dos fármacos
8.
J Neurosci ; 36(44): 11171-11184, 2016 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-27807161

RESUMO

Zolpidem, a GABAA receptor-positive modulator, is the gold-standard drug for treating insomnia. Zolpidem prolongs IPSCs to decrease sleep latency and increase sleep time, effects that depend on α2 and/or α3 subunit-containing receptors. Compared with natural NREM sleep, zolpidem also decreases the EEG power, an effect that depends on α1 subunit-containing receptors, and which may make zolpidem-induced sleep less optimal. In this paper, we investigate whether zolpidem needs to potentiate only particular GABAergic pathways to induce sleep without reducing EEG power. Mice with a knock-in F77I mutation in the GABAA receptor γ2 subunit gene are zolpidem-insensitive. Using these mice, GABAA receptors in the frontal motor neocortex and hypothalamic (tuberomammillary nucleus) histaminergic-neurons of γ2I77 mice were made selectively sensitive to zolpidem by genetically swapping the γ2I77 subunits with γ2F77 subunits. When histamine neurons were made selectively zolpidem-sensitive, systemic administration of zolpidem shortened sleep latency and increased sleep time. But in contrast to the effect of zolpidem on wild-type mice, the power in the EEG spectra of NREM sleep was not decreased, suggesting that these EEG power-reducing effects of zolpidem do not depend on reduced histamine release. Selective potentiation of GABAA receptors in the frontal cortex by systemic zolpidem administration also reduced sleep latency, but less so than for histamine neurons. These results could help with the design of new sedatives that induce a more natural sleep. SIGNIFICANCE STATEMENT: Many people who find it hard to get to sleep take sedatives. Zolpidem (Ambien) is the most widely prescribed "sleeping pill." It makes the inhibitory neurotransmitter GABA work better at its receptors throughout the brain. The sleep induced by zolpidem does not resemble natural sleep because it produces a lower power in the brain waves that occur while we are sleeping. We show using mouse genetics that zolpidem only needs to work on specific parts and cell types of the brain, including histamine neurons in the hypothalamus, to induce sleep but without reducing the power of the sleep. This knowledge could help in the design of sleeping pills that induce a more natural sleep.


Assuntos
Neocórtex/fisiologia , Neurônios/fisiologia , Piridinas/administração & dosagem , Receptores de GABA-A/metabolismo , Sono/efeitos dos fármacos , Sono/fisiologia , Animais , Relação Dose-Resposta a Droga , Feminino , Histamínicos/administração & dosagem , Hipnóticos e Sedativos/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neocórtex/citologia , Neocórtex/efeitos dos fármacos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Medicamentos Indutores do Sono/administração & dosagem , Zolpidem
9.
J Mater Sci Mater Med ; 28(7): 103, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28534286

RESUMO

Research on the incorporation of cutting-edge nano-antibacterial agent for designing dental materials with potent and long-lasting antibacterial property is demanding and provoking work. In this study, a novel resin-based dental material containing photocurable core-shell AgBr/cationic polymer nanocomposite (AgBr/BHPVP) was designed and developed. The shell of polymerizable cationic polymer not only provided non-releasing antibacterial capability for dental resins, but also had the potential to polymerize with other methacrylate monomers and prevented nanoparticles from aggregating in the resin matrix. As a result, incorporation of AgBr/BHPVP nanocomposites did not adversely affect the flexural strength and modulus but greatly increased the Vicker's hardness of resin disks. By continuing to release Ag+ ions without the impact of anaerobic environment, resins containing AgBr/BHPVP nanoparticles are particularly suitable to combat anaerobic cariogenic bacteria. By reason of the combined bactericidal effect of the contact-killing cationic polymers and the releasing-killing Ag+ ions, AgBr/BHPVP-containing resin disks had potent bactericidal activity against S. mutans. The long-lasting antibacterial activity was also achieved through the sustained release of Ag+ ions due to the core-shell structure of the nanocomposites. The results of macrophage cytotoxicity showed that the cell viability of dental resins loading less than 1.0 wt% AgBr/BHPVP was close to that of neat resins. The AgBr/BHPVP-containing dental resin with dual bactericidal capability and long term antimicrobial effect is a promising material aimed at preventing second caries and prolonging the longevity of resin composite restorations.


Assuntos
Brometos/administração & dosagem , Preparações de Ação Retardada/administração & dosagem , Cura Luminosa de Adesivos Dentários/métodos , Nanocápsulas/administração & dosagem , Nanocompostos/administração & dosagem , Resinas Sintéticas/síntese química , Compostos de Prata/administração & dosagem , Streptococcus mutans/efeitos dos fármacos , Antibacterianos/administração & dosagem , Antibacterianos/química , Antibacterianos/efeitos da radiação , Brometos/química , Brometos/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada/síntese química , Preparações de Ação Retardada/efeitos da radiação , Difusão , Combinação de Medicamentos , Dureza/efeitos dos fármacos , Luz , Nanocápsulas/química , Nanocápsulas/efeitos da radiação , Nanocápsulas/ultraestrutura , Nanocompostos/química , Nanocompostos/efeitos da radiação , Poliaminas/química , Poliaminas/efeitos da radiação , Polieletrólitos , Resinas Sintéticas/administração & dosagem , Resinas Sintéticas/efeitos da radiação , Compostos de Prata/química , Compostos de Prata/efeitos da radiação
10.
Front Med (Lausanne) ; 11: 1321599, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38384419

RESUMO

Introduction: Critically ill patients are more susceptible to malnutrition due to their severe illness. Moreover, elderly patients who are critically ill lack specific nutrition recommendations, with nutritional care in the intensive care units (ICUs) deplorable for the elderly. This study aims to investigate nutrition treatment and its correlation to mortality in elderly patients who are critically ill in intensive care units. Method: A multiple-center prospective cohort study was conducted in China from 128 intensive care units (ICUs). A total of 1,238 elderly patients were included in the study from 26 April 2017. We analyzed the nutrition characteristics of elderly patients who are critically ill, including initiated timing, route, ways of enteral nutrition (EN), and feeding complications, including the adverse aspects of feeding, acute gastrointestinal injury (AGI), and feeding interruption. Multivariate logistic regression analysis was used to screen out the impact of nutrition treatment on a 28-day survival prognosis of elderly patients in the ICU. Result: A total of 1,238 patients with a median age of 76 (IQR 70-83) were enrolled in the study. The Sequential Organ Failure (SOFA) median score was 7 (interquartile range: IQR 5-10) and the median Acute Physiology and Chronic Health Evaluation (APACHE) II was 21 (IQR 16-25). The all-cause mortality score was 11.6%. The percentage of nutritional treatment initiated 24 h after ICU admission was 58%, with an EN of 34.2% and a parenteral nutrition (PN) of 16.0% in elderly patients who are critically ill. Patients who had gastrointestinal dysfunction with AGI stage from 2 to 4 were 25.2%. Compared to the survivors' group, the non-survivors group had a lower ratio of EN delivery (57% vs. 71%; p = 0.015), a higher ratio of post-pyloric feeding (9% vs. 2%; p = 0.027), and higher frequency of feeding interrupt (24% vs. 17%, p = 0.048). Multivariable logistics regression analysis showed that patients above 76 years old with OR (odds ratio) 2.576 (95% CI, 1.127-5.889), respiratory rate > 22 beats/min, and ICU admission for 24 h were independent risk predictors of the 28-day mortality study in elderly patients who are critically ill. Similarly, other independent risk predictors of the 28-day mortality study were those with an OR of 2.385 (95%CI, 1.101-5.168), lactate >1.5 mmol/L, and ICU admission for 24 h, those with an OR of 7.004 (95%CI, 2.395-20.717) and early PN delivery within 24 h of ICU admission, and finally those with an OR of 5.401 (95%CI, 1.175-24.821) with EN delivery as reference. Conclusion: This multi-center prospective study describes clinical characteristics, the mode and timing of nutrition treatment, frequency of AGI, and adverse effects of nutrition in elderly ICU patients. According to this survey, ICU patients with early PN delivery, older age, faster respiratory rate, and higher lactate level may experience poor prognosis.

11.
Reg Anesth Pain Med ; 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233353

RESUMO

INTRODUCTION: Local anesthetic-induced neurotoxicity contributes to perioperative nerve damage; however, the underlying mechanisms remain unclear. Here, we investigated the role of the paraventricular thalamus (PVT)-nucleus accumbens (NAc) projections in neurotoxicity induced by ropivacaine, a local anesthetic agent. METHODS: Ropivacaine (58 mg/kg, intraperitoneal administration) was used to construct the local anesthetic systemic toxicity (LAST) mice model. We first identified neural projections from the PVT to the NAc through the expression of a retrograde tracer and virus. The inhibitory viruses (rAAV-EF1α-DIO-hm4D(Gi)-mCherry-WPREs: AAV2/retro and rAAV-CaMKII-CRE-WPRE-hGh: AAV2/9) were injected into the mice model to assess the effects of the specific inhibition of the PVT-NAc pathway on neurological behaviors in the presence of clozapine-N-oxide. The inhibition of the PVT-NAc pathway was evaluated by immunofluorescence staining of c-Fos-positive neurons and Ca2+ signals in CaMKIIa neurons. RESULTS: We successfully identified a circuit connecting the PVT and NAc in C57BL/6 mice. Ropivacaine administration induced the activation of the PVT-NAc pathway and seizures. Specific inhibition of NAc-projecting CaMKII neurons in the PVT was sufficient to inhibit the neuronal activity in the NAc, which subsequently decreased ropivacaine-induced neurotoxicity. CONCLUSION: These results reveal the presence of a dedicated PVT-NAc circuit that regulates local anesthetic-induced neurotoxicity and provide a potential mechanistic explanation for the treatment and prevention of LAST.

12.
Nat Commun ; 15(1): 3254, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627395

RESUMO

The past century has witnessed a large number of reports on the Z/E isomerization of alkenes. However, the vast majority of them are still limited to the isomerization of di- and tri-substituted alkenes. The stereospecific Z/E isomerization of tetrasubstituted alkenes remains to be an underdeveloped area, thus lacking in a stereodivergent synthesis of axially chiral alkenes. Herein we report the atroposelective synthesis of tetrasubstituted alkene analogues by asymmetric allylic substitution-isomerization, followed by their Z/E isomerization via triplet energy transfer photocatalysis. In this regard, the stereodivergent synthesis of axially chiral N-vinylquinolinones is achieved efficiently. Mechanistic studies indicate that the benzylic radical generation and distribution are two key factors for preserving the enantioselectivities of axially chiral compounds.

13.
Curr Res Neurobiol ; 6: 100130, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38694514

RESUMO

A fundamental problem in neuroscience is how neurons select for their many inputs. A common assumption is that a neuron's selectivity is largely explained by differences in excitatory synaptic input weightings. Here we describe another solution to this important problem. We show that within the first order visual thalamus, the type of inhibition provided by thalamic interneurons has the potential to alter the input selectivity of thalamocortical neurons. To do this, we developed conductance injection protocols to compare how different types of synchronous and asynchronous GABA release influence thalamocortical excitability in response to realistic patterns of retinal ganglion cell input. We show that the asynchronous GABA release associated with tonic inhibition is particularly efficient at maintaining information content, ensuring that thalamocortical neurons can distinguish between their inputs. We propose a model where alterations in GABA release properties results in rapid changes in input selectivity without requiring structural changes in the network.

14.
bioRxiv ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37662298

RESUMO

To understand the neural basis of behavior, it is essential to sensitively and accurately measure neural activity at single neuron and single spike resolution. Extracellular electrophysiology delivers this, but it has biases in the neurons it detects and it imperfectly resolves their action potentials. To minimize these limitations, we developed a silicon probe with much smaller and denser recording sites than previous designs, called Neuropixels Ultra (NP Ultra). This device samples neuronal activity at ultra-high spatial density (~10 times higher than previous probes) with low noise levels, while trading off recording span. NP Ultra is effectively an implantable voltage-sensing camera that captures a planar image of a neuron's electrical field. We use a spike sorting algorithm optimized for these probes to demonstrate that the yield of visually-responsive neurons in recordings from mouse visual cortex improves up to ~3-fold. We show that NP Ultra can record from small neuronal structures including axons and dendrites. Recordings across multiple brain regions and four species revealed a subset of extracellular action potentials with unexpectedly small spatial spread and axon-like features. We share a large-scale dataset of these brain-wide recordings in mice as a resource for studies of neuronal biophysics. Finally, using ground-truth identification of three major inhibitory cortical cell types, we found that these cell types were discriminable with approximately 75% success, a significant improvement over lower-resolution recordings. NP Ultra improves spike sorting performance, detection of subcellular compartments, and cell type classification to enable more powerful dissection of neural circuit activity during behavior.

15.
J Neurosci ; 32(38): 13062-75, 2012 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-22993424

RESUMO

The activity of histaminergic neurons in the tuberomammillary nucleus (TMN) of the hypothalamus correlates with an animal's behavioral state and maintains arousal. We examined how GABAergic inputs onto histaminergic neurons regulate this behavior. A prominent hypothesis, the "flip-flop" model, predicts that increased and sustained GABAergic drive onto these cells promotes sleep. Similarly, because of the histaminergic neurons' key hub-like place in the arousal circuitry, it has also been suggested that anesthetics such as propofol induce loss of consciousness by acting primarily at histaminergic neurons. We tested both these hypotheses in mice by genetically removing ionotropic GABA(A) or metabotropic GABA(B) receptors from histidine decarboxylase-expressing neurons. At the cellular level, histaminergic neurons deficient in synaptic GABA(A) receptors were significantly more excitable and were insensitive to the anesthetic propofol. At the behavioral level, EEG profiles were recorded in nontethered mice over 24 h. Surprisingly, GABAergic transmission onto histaminergic neurons had no effect in regulating the natural sleep-wake cycle and, in the case of GABA(A) receptors, for propofol-induced loss of righting reflex. The latter finding makes it unlikely that the histaminergic TMN has a central role in anesthesia. GABA(B) receptors on histaminergic neurons were dispensable for all behaviors examined. Synaptic inhibition of histaminergic cells by GABA(A) receptors, however, was essential for habituation to a novel environment.


Assuntos
Neurônios GABAérgicos/fisiologia , Histamina/metabolismo , Inibição Neural/fisiologia , Sono/fisiologia , Inconsciência/fisiopatologia , Vigília/fisiologia , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Animais Recém-Nascidos , Biofísica , Encéfalo/metabolismo , Estimulação Elétrica , Eletroencefalografia , Eletromiografia , Comportamento Exploratório/efeitos dos fármacos , Comportamento Exploratório/fisiologia , Neurônios GABAérgicos/efeitos dos fármacos , Proteínas de Fluorescência Verde/genética , Habituação Psicofisiológica/genética , Histidina Descarboxilase/genética , Histidina Descarboxilase/metabolismo , Hipnóticos e Sedativos/efeitos adversos , Região Hipotalâmica Lateral/citologia , Técnicas In Vitro , Lisina/análogos & derivados , Lisina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação/genética , Inibição Neural/efeitos dos fármacos , Inibição Neural/genética , Técnicas de Patch-Clamp , Propofol/efeitos adversos , Proteínas/genética , Proteínas/metabolismo , RNA Mensageiro/metabolismo , RNA não Traduzido , Receptores de GABA-A/deficiência , Reflexo/efeitos dos fármacos , Reflexo/genética , Sono/efeitos dos fármacos , Sono/genética , Inconsciência/induzido quimicamente , Vigília/genética , beta-Galactosidase/metabolismo
16.
Org Lett ; 25(30): 5661-5665, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37471513

RESUMO

A series of bistetrazole-based energetic salts bearing a nitrogen-rich fused ring were designed and synthesized. Among them, compounds 4-10 showed good detonation properties and excellent thermostability. By treating nitrogen-rich fused ring 3 with concentrated hydrochloric acid, a new type of Dimroth rearrangement was observed that afforded compound 12 efficiently. This new transformation herein constitutes a valuable addition to the Dimroth rearrangement.

17.
PLoS One ; 18(3): e0278053, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36996085

RESUMO

Monosynaptically restricted rabies viruses have been used for more than a decade for synaptic connectivity tracing. However, the verisimilitude of quantitative conclusions drawn from these experiments is largely unknown. The primary reason is the simple metrics commonly used, which generally disregard the effect of starter cell numbers. Here we present an experimental dataset with a broad range of starter cell numbers and explore their relationship with the number of input cells across the brain using descriptive statistics and modelling. We show that starter cell numbers strongly affect input fraction and convergence index measures, making quantitative comparisons unreliable. Furthermore, we suggest a principled way to analyse rabies derived connectivity data by taking advantage of the starter vs input cell relationship that we describe and validate across independent datasets.


Assuntos
Vírus da Raiva , Raiva , Humanos , Encéfalo
18.
ACS Appl Mater Interfaces ; 15(12): 15311-15320, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36926825

RESUMO

An innovative synthesis of 5-((1H-tetrazol-5-yl)methyl)-4H-1,2,4-triazole-3,4-diamine (TMT) based on triazole and tetrazole frameworks bearing double amino groups was reported. It is worth mentioning that TMT is insensitive to impact and friction (IS > 40 J, FS > 360 N), thus enabling it to have an exceptional thermal decomposition behavior that is superior to RDX and TNT. Meanwhile, it also has relatively high energetic performance (Dv = 8.417 km/s). A series of energy-containing salts TMT-1-8 were also investigated for their potential applications. Except for TMT-4 and TMT-7, the remaining nitrogen-rich salts have initial decomposition temperatures above 200 °C. Furthermore, the salts with positive heat generation all have extraordinary gas production, especially for TMT-1 (Vo = 840.5 dm3/kg), TMT-2 (Vo = 803.9 dm3/kg), and TMT-7 (Vo = 844.3 dm3/kg). The low mechanical sensitivities of the TMT series were discovered, and a majority of them have impact sensitivities exceeding 40 J with friction sensitivities exceeding 360 N which are superior to TNT (IS = 15 J, FS = 353 N). The intermolecular and intramolecular interactions of the crystals TMT-1-3 were explored by Hirshfeld surfaces, 2D fingerprint plots, noncovalent interaction (NCI) analysis, and electrostatic potential surface analysis to understand the physicochemical property changes in relation to the structure. Consequently, this novel tri/tetrazole and polyamine system as a promising material provides the impetus for the development of gas generators and propellants.

19.
ACS Appl Mater Interfaces ; 15(4): 5720-5731, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36662519

RESUMO

Fe-based materials containing Fe-Nx sites have emerged as promising electrocatalysts in the oxygen reduction reaction (ORR), but they still suffer structural instability which may lead to loss of catalytic activity. Herein, a novel electrocatalyst Fe3C-FeSA@3DCN with the coexistence of Fe3C nanoparticles and Fe single atoms (FeSA) in a three-dimensional conductive network (3DCN) is prepared via lattice confinement and defect trapping strategies with an Fe atomic loading of as high as 4.36%. In the ORR process, the limiting current density of Fe3C-FeSA@3DCN reaches 5.72 mA cm-2, with an onset potential of 0.926 V and a Tafel slope of 66 mV/decade, showing better catalytic activity and stability than Pt/C catalysts. Notably, its assembled aqueous and solid-state Zn-air batteries (ZABs) achieve peak power densities of 166 and 56 mW cm-2, respectively, with a long service life of up to 200 h at a current density of 5 mA cm-2. In addition, the assembled ZAB can provide a constant voltage on activated carbon electrodes to perform capacitive deionization to adsorb different ions. The importance of the Fe species active sites generated by Fe3C and FeSA in the material for ORR activity to boost the electron transfer and mass transfer is demonstrated by a simple selective poisoning experiment.

20.
Front Cell Infect Microbiol ; 13: 1121444, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37056709

RESUMO

Objectives: We aimed to evaluate the association between ß-blocker therapy and mortality in patients with sepsis. Methods: Patients with sepsis were selected from the Medical Information Mart for Intensive Care (MIMIC)-III. Propensity score matching (PSM) was used to balance the baseline differences. A multivariate Cox regression model was used to assess the relationship between ß-blocker therapy and mortality. The primary outcome was the 28-day mortality. Results: A total of 12,360 patients were included in the study, involving 3,895 who received ß-blocker therapy and 8,465 who did not. After PSM, 3,891 pairs of patients were matched. The results showed that ß-blockers were associated with improved 28- (hazards ratio (HR) 0.78) and 90-day (HR 0.84) mortality. Long-acting ß-blockers were associated with improved 28-day survival (757/3627 [20.9%] vs. 583/3627 [16.1%], P < 0.001, HR0.76) and 90-day survival (1065/3627 [29.4%] vs.921/3627 [25.4%], P < 0.001, HR 0.77). Short-acting ß-blocker treatment did not reduce the 28-day and 90-day mortality (61/264 [23.1%] vs. 63/264 [23.9%], P = 0.89 and 83/264 [31.4%] vs. 89/264 [31.7%], P = 0.8, respectively). Conclusions: ß-blockers were associated with improved 28- and 90-day mortality in patients with sepsis and septic shock. Long-acting ß-blocker therapy may have a protective role in patients with sepsis, reducing the 28-day and 90-day mortality. However, short-acting ß-blocker (esmolol) treatment did not reduce the mortality in sepsis.


Assuntos
Sepse , Choque Séptico , Humanos , Pontuação de Propensão , Sepse/tratamento farmacológico , Antagonistas Adrenérgicos beta/uso terapêutico , Choque Séptico/tratamento farmacológico , Estudos Retrospectivos
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