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1.
Mol Cell ; 73(5): 1015-1027.e7, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30711376

RESUMO

TCRs recognize cognate pMHCs to initiate T cell signaling and adaptive immunity. Mechanical force strengthens TCR-pMHC interactions to elicit agonist-specific catch bonds to trigger TCR signaling, but the underlying dynamic structural mechanism is unclear. We combined steered molecular dynamics (SMD) simulation, single-molecule biophysical approaches, and functional assays to collectively demonstrate that mechanical force induces conformational changes in pMHCs to enhance pre-existing contacts and activates new interactions at the TCR-pMHC binding interface to resist bond dissociation under force, resulting in TCR-pMHC catch bonds and T cell activation. Intriguingly, cancer-associated somatic mutations in HLA-A2 that may restrict these conformational changes suppressed TCR-pMHC catch bonds. Structural analysis also indicated that HLA polymorphism might alter the equilibrium of these conformational changes. Our findings not only reveal critical roles of force-induced conformational changes in pMHCs for activating TCR-pMHC catch bonds but also have implications for T cell-based immunotherapy.


Assuntos
Imunidade Adaptativa , Antígeno HLA-A2/imunologia , Mecanotransdução Celular , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/imunologia , Animais , Células HEK293 , Antígeno HLA-A2/química , Antígeno HLA-A2/genética , Antígeno HLA-A2/metabolismo , Humanos , Hibridomas , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Simulação de Dinâmica Molecular , Mutação , Ligação Proteica , Conformação Proteica , Receptores de Antígenos de Linfócitos T/química , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Imagem Individual de Molécula/métodos , Relação Estrutura-Atividade , Linfócitos T/metabolismo
2.
EMBO J ; 41(2): e107739, 2022 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34913508

RESUMO

Stimulatory immune receptor NKG2D binds diverse ligands to elicit differential anti-tumor and anti-virus immune responses. Two conflicting degeneracy recognition models based on static crystal structures and in-solution binding affinities have been considered for almost two decades. Whether and how NKG2D recognizes and discriminates diverse ligands still remain unclear. Using live-cell-based single-molecule biomechanical assay, we characterized the in situ binding kinetics of NKG2D interacting with different ligands in the absence or presence of mechanical force. We found that mechanical force application selectively prolonged NKG2D interaction lifetimes with the ligands MICA and MICB, but not with ULBPs, and that force-strengthened binding is much more pronounced for MICA than for other ligands. We also integrated steered molecular dynamics simulations and mutagenesis to reveal force-induced rotational conformational changes of MICA, involving formation of additional hydrogen bonds on its binding interface with NKG2D, impeding MICA dissociation under force. We further provided a kinetic triggering model to reveal that force-dependent affinity determines NKG2D ligand discrimination and its downstream NK cell activation. Together, our results demonstrate that NKG2D has a discrimination power to recognize different ligands, which depends on selective mechanical force-induced ligand conformational changes.


Assuntos
Subfamília K de Receptores Semelhantes a Lectina de Células NK/química , Sítios de Ligação , Células Cultivadas , Antígenos de Histocompatibilidade Classe I/química , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Células K562 , Ligantes , Fenômenos Mecânicos , Simulação de Dinâmica Molecular , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Ligação Proteica , Imagem Individual de Molécula
3.
Circ Res ; 134(3): 252-265, 2024 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166470

RESUMO

BACKGROUND: Intracellular Ca2+ cycling determines myocardial contraction and relaxation in response to physiological demands. SERCA2a (sarcoplasmic/endoplasmic reticulum Ca2+-ATPase 2a) is responsible for the sequestration of cytosolic Ca2+ into intracellular stores during cardiac relaxation, and its activity is reversibly inhibited by PLN (phospholamban). However, the regulatory hierarchy of SERCA2a activity remains unclear. METHODS: Cardiomyocyte-specific ZBTB20 knockout mice were generated by crossing ZBTB20flox mice with Myh6-Cre mice. Echocardiography, blood pressure measurements, Langendorff perfusion, histological analysis and immunohistochemistry, quantitative reverse transcription-PCR, Western blot analysis, electrophysiological measurements, and chromatin immunoprecipitation assay were performed to clarify the phenotype and elucidate the molecular mechanisms. RESULTS: Specific ablation of ZBTB20 in cardiomyocyte led to a significant increase in basal myocardial contractile parameters both in vivo and in vitro, accompanied by an impairment in cardiac reserve and exercise capacity. Moreover, the cardiomyocytes lacking ZBTB20 showed an increase in sarcoplasmic reticular Ca2+ content and exhibited a remarkable enhancement in both SERCA2a activity and electrically stimulated contraction. Mechanistically, PLN expression was dramatically reduced in cardiomyocytes at the mRNA and protein levels by ZBTB20 deletion or silencing, and PLN overexpression could largely restore the basal contractility in ZBTB20-deficient cardiomyocytes. CONCLUSIONS: These data point to ZBTB20 as a fine-tuning modulator of PLN expression and SERCA2a activity, thereby offering new perspective on the regulation of basal contractility in the mammalian heart.


Assuntos
Miocárdio , Retículo Sarcoplasmático , Animais , Camundongos , Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Mamíferos , Camundongos Knockout , Contração Miocárdica/fisiologia , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Retículo Sarcoplasmático/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo
4.
Med Sci Monit ; 30: e943463, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38509664

RESUMO

BACKGROUND Intraoperative and postoperative hypothermia of patients can be caused by the use of anesthetic drugs and the complicated and time-consuming procedures of interventional surgery. This retrospective study included 184 patients to investigate the incidence and factors associated with hypothermia during intraoperative anesthesia in a single center in China between January and October 2023. MATERIAL AND METHODS A convenient sampling method was used to select 184 patients who underwent general anesthesia intervention in a tertiary hospital in Sichuan Province from January to October 2023 as the study population. The independent factors influencing the occurrence of intraoperative hypothermia were analyzed. A survey was conducted to collect 5 demographic factors, 4 preoperative-related factors, and 10 surgically related factors. According to the occurrence of intraoperative hypothermia, the independent influencing factors of unplanned hypothermia during perioperative period were further analyzed. RESULTS Among 184 patients, 64 (34.78%) experienced perioperative unplanned hypothermia, of which 5 (7.81%) cases occurred before the start of surgery, 7 (10.94%) occurred before the start of surgery after anesthesia, and 52 (81.25%) occurred during surgery. Logistic regression analysis showed that body temperature at the beginning of surgery (P<0.001), set operating room temperature (P<0.001), duration of anesthesia (P=0.006), and age (P=0.001) were independent influencing factors for unplanned hypothermia during perioperative period. CONCLUSIONS The incidence of intraoperative hypothermia is high in patients undergoing general anesthesia interventions. Age, duration of anesthesia, set operating room temperature, and body temperature at the beginning of the operation were independent influencing factors for the occurrence of unplanned hypothermia during the perioperative period.


Assuntos
Hipotermia , Humanos , Hipotermia/etiologia , Hipotermia/complicações , Temperatura Corporal , Centros de Atenção Terciária , Estudos Retrospectivos , Anestesia Geral/efeitos adversos , Complicações Intraoperatórias/epidemiologia , Complicações Intraoperatórias/etiologia
5.
BMC Pediatr ; 24(1): 82, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38279097

RESUMO

BACKGROUND: Severe neonatal hyperbilirubinemia could lead to kernicterus and neonatal death. This study aimed to analyze the association between single nucleotide polymorphisms in genes involved in bilirubin metabolism and the incidence of severe hyperbilirubinemia. METHODS: A total of 144 neonates with severe hyperbilirubinemia and 50 neonates without or mild hyperbilirubinemia were enrolled in 3 institutions between 2019 and 2020. Twelve polymorphisms of 5 genes (UGT1A1, SLCO1B1, SLCO1B3, BLVRA, and HMOX1) were analyzed by PCR amplification of genomic DNA. Genotyping was performed using an improved multiplex ligation detection reaction technique based on ligase detection reaction. RESULTS: The frequencies of the A allele in UGT1A1-rs4148323 and the C allele in SLCO1B3-rs2417940 in the severe hyperbilirubinemia group (30.2% and 90.6%, respectively) were significantly higher than those in the controls (30.2% vs.13.0%, 90.6% vs. 78.0%, respectively, both p < 0.05). Haplotype analysis showed the ACG haplotype of UGT1A1 were associated with an increased hyperbilirubinemia risk (OR 3.122, p = 0.001), whereas the GCG haplotype was related to a reduced risk (OR 0.523, p = 0.018). CONCLUSION: The frequencies of the A allele in rs4148323 and the C allele in rs2417940 are highly associated with the incidence of severe hyperbilirubinemia in Chinese Han neonates. TRIAL REGISTRATION: Trial registration number:ChiCTR1800020424; Date of registration:2018-12-29.


Assuntos
Hiperbilirrubinemia Neonatal , Polimorfismo de Nucleotídeo Único , Recém-Nascido , Humanos , Transportador 1 de Ânion Orgânico Específico do Fígado/genética , Alelos , Hiperbilirrubinemia Neonatal/genética , Glucuronosiltransferase/genética , China/epidemiologia , Membro 1B3 da Família de Transportadores de Ânion Orgânico Carreador de Soluto/genética , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo
6.
Angew Chem Int Ed Engl ; 63(6): e202314355, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-37914669

RESUMO

Cheap, stable and easy-to-handle Werner ammine salts have been known for more than a century; but they have been rarely used in organic synthesis. Herein, we report that the Werner hexammine complex [Ni(NH3 )6 ]Cl2 can be used as both a nitrogen and a catalytic nickel source that allow for the efficient amination of aryl chlorides in the presence of a catalytic amount of bipyridine ligand under the irradiation of 390-395 nm light without the need of any additional catalysts. More than 80 aryl chlorides, including more than 20 drug molecules, were aminated, demonstrating the practicality and generality of this method in synthetic chemistry. A slow NH3 release mechanism is in operation, obviating the problem of catalyst poisoning. Still interestingly, we show that the Werner salt can be easily recovered and reused, solving the problem of difficult recovery of transition metal nickel catalysts. The protocol thus provides an efficient new strategy for the synthesis of primary aryl amines.

7.
J Neurosci ; 42(41): 7833-7847, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-36414013

RESUMO

Autism is characterized by two key diagnostic criteria including social deficits and repetitive behaviors. Although recent studies implicated ventral striatum in social deficits and dorsal striatum in repetitive behaviors, here we revealed coexisting and opposite morphologic and functional alterations in the dorsostriatal direct and indirect pathways, and such alterations in these two pathways were found to be responsible, respectively, for the two abovementioned different autism-like behaviors exhibited by male mice prenatally exposed to valproate. The alteration in direct pathway was characterized by a potentiated state of basal activity, with impairment in transient responsiveness of D1-MSNs during social exploration. Concurrent alteration in indirect pathway was a depressed state of basal activity, with enhancement in transient responsiveness of D2-MSNs during repetitive behaviors. A causal relationship linking such differential alterations in these two pathways to the coexistence of these two autism-like behaviors was demonstrated by the cell type-specific correction of abnormal basal activity in the D1-MSNs and D2-MSNs of valproate-exposed mice. The findings support those differential alterations in two striatal pathways mediate the two coexisting autism-like behavioral abnormalities, respectively. This result will help in developing therapeutic options targeting these circuit alterations.SIGNIFICANCE STATEMENT Autism is characterized by two key diagnostic criteria including social deficits and repetitive behaviors. Although a number of recent studies have implicated ventral striatum in social deficits and dorsal striatum in repetitive behaviors, but social behaviors need to be processed by a series of actions, and repetitive behaviors, especially the high-order repetitive behaviors such as restrictive interests, have its scope to cognitive and emotional domains. The current study, for the first time, revealed that prenatal valproate exposure induced coexisting and differential alterations in the dorsomedial striatal direct and indirect pathways, and that these alterations mediate the two coexisting autism-like behavioral abnormalities, respectively. This result will help in developing therapeutic options targeting these circuit alterations to address the behavioral abnormalities.


Assuntos
Transtorno Autístico , Estriado Ventral , Camundongos , Animais , Masculino , Transtorno Autístico/metabolismo , Ácido Valproico , Comportamento Social , Estriado Ventral/metabolismo
8.
Acta Oncol ; 62(12): 1873-1879, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37909907

RESUMO

BACKGROUND/PURPOSE: Gastric dose parameters comparison for deep inspiration breath-hold (DIBH) or free breathing (FB) mode during radiotherapy (RT) for left-sided breast cancer patients (LSBCPs) has not been investigated before. This study aimed to analyze the impact of Active Breath Coordinator (ABC)-DIBH technique on the dose received by the stomach during RT for LSBCPs and to provide organ-specific dosimetric parameters. MATERIALS AND METHODS: The study included 73 LSBCPs. The dosimetric parameters of the stomach were compared between FB and DIBH mode. The correlation between the stomach volume and dosimetric parameters was analyzed. RESULTS: Compared to FB mode, statistically significant reductions were observed in gastric dose parameters in ABC-DIBH mode, including Dmax (46.60 vs 17.25, p < 0.001), D1cc (38.42 vs 9.60, p < 0.001), Dmean (4.10 vs 0.80, p < 0.001), V40Gy (0.50 vs 0.00, p < 0.001), V30Gy (6.30 vs 0.00, p < 0.001), V20Gy (20.80 vs 0.00, p < 0.001), V10Gy (51.10 vs 0.77, p < 0.001), and V5Gy (93.20 vs 9.60, p < 0.001). ABC-DIBH increased the distance between the stomach and the breast PTV when compared to FB, from 1.3 cm to 2.8 cm (p < 0.001). Physiologic decrease in stomach volume was not found from FB to ABC-DIBH (415.54 cm3 vs 411.61 cm3, p = 0.260). The stomach volume showed a positive correlation with V40Gy (r2 = 0.289; p < 0.05), V30Gy (r2 = 0.287; p < 0.05), V20Gy (r2 = 0.343; p < 0.05), V10Gy (r2 = 0.039; p < 0.001), V5Gy (r2 = 0.439; p < 0.001), Dmax (r2 = 0.269; p < 0.05) and D1cc (r2 = 0.278; p < 0.05) in FB mode. While in ABC-DIBH mode, most stomach dosimetric parameters were not correlated with gastric volume. CONCLUSIONS: The implementation of ABC-DIBH in LSBCPs radiotherapy resulted in lower irradiation of the stomach. Larger stomach volume was associated with statistically significantly higher dose irradiation in FB mode. To reduce radiotherapy related side effects in FB mode, patients should be fast for at least 2 hours before the CT simulation and treatment.


Assuntos
Neoplasias da Mama , Neoplasias Unilaterais da Mama , Humanos , Feminino , Neoplasias da Mama/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Dosagem Radioterapêutica , Suspensão da Respiração , Neoplasias Unilaterais da Mama/radioterapia , Estômago , Doses de Radiação , Coração/efeitos da radiação , Órgãos em Risco/efeitos da radiação
9.
Oral Dis ; 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36975762

RESUMO

OBJECTIVE: To compare the personalities, social avoidance and distress, and anxiety status of Chinese patients with and without objective halitosis, and investigate the association among these psychological disorders. METHODS: Patients who complained of bad breath and diagnosed with objective halitosis were enrolled into the halitosis group, while patients without objective halitosis were enrolled into the control group. The questionnaires included the sociodemographic profile of the participants, Eysenck Personality Questionnaire (EPQ), Social Avoidance and Distress Scale (SAD), and Beck Anxiety Inventory (BAI). RESULTS: A total of 280 patients were assigned into objective halitosis group (n = 146) and control group (n = 134). The extraversion subscales (E) score of the EPQ in the halitosis group were significantly lower than that in the control group (p = 0.001). The total SAD score and proportion of patients with anxiety symptoms in the BAI scale in the objective halitosis was significantly higher than that in the control group (p < 0.05). There was a negative correlation between the extraversion subscale and the total SAD score, Social Avoidance and Social Distress subscales (p < 0.001). CONCLUSION: Patients with objective halitosis have more introverted personality traits and are more likely to have social avoidance and distress than the nonhalitosis population.

10.
Altern Ther Health Med ; 29(1): 156-162, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36074963

RESUMO

Objective: To compare the analgesic effect of oral sucrose water (Su) vs local application of lidocaine liposome (LC) in blood collection and intramuscular injection in neonates. Methods: A total of 300 neonates admitted to Sichuan Provincial People's Hospital in China between June 2019 and December 2021 who were to receive intramuscular injection and heel blood collection were enrolled in the study. The neonates were assigned to one of the following groups (n = 30 in each): control, 30% Su, 25% Su, 24% Su, 12% Su, 8% Su, LC 15-min, LC 30-min, LC 45-min or the combination group. The groups received different concentrations of Su or the application of LC liposome at different timepoints and the control group was given no analgesia. Before and after puncture, the Neonatal Facial Coding System-Revised (NFCS-R) was used for pain evaluation in the neonates. The heart rate (HR), respiratory rate, blood oxygen saturation (SpO2) and blood pressure (BP) in each group were compared, and the starting and ending time of crying and latent crying time were recorded and analyzed. After the optimal concentration of Su and optimal application time of LC were understood, the combination group was used to evaluate the analgesic effect of Su combined with LC. Results: Using various concentrations of Su, neonate pain was alleviated to varying degrees; 24%, 25%, and 30% Su did not reveal any difference in various investigation items, although their effect was superior to 8% and 12% Su. The LC 30-min and LC 45-min groups performed better than the LC 15-min group with regard to NFCS-R score, vital signs and BP. However, no notable difference was observed between the LC 15-min and LC 45-min groups in latent time. Moreover, the combination of 24% Su and application of LC 30 minutes before puncture provided a better analgesic effect than a single anesthesia intervention. Conclusion: The combination of 24% Su and the application of LC 30 minutes before puncture delivered better analgesic effect than a single anesthesia intervention alone.


Assuntos
Lidocaína , Lipossomos , Recém-Nascido , Humanos , Lidocaína/uso terapêutico , Lipossomos/uso terapêutico , Sacarose/uso terapêutico , Injeções Intramusculares , Dor/tratamento farmacológico , Analgésicos
11.
BMC Biol ; 20(1): 108, 2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35550070

RESUMO

BACKGROUND: Cannabinoids and their derivatives attract strong interest due to the tremendous potential of their psychoactive effects for treating psychiatric disorders and symptoms. However, their clinical application is restricted by various side-effects such as impaired coordination, anxiety, and learning and memory disability. Adverse impact on dorsal striatum-dependent learning is an important side-effect of cannabinoids. As one of the most important forms of learning mediated by the dorsal striatum, reinforcement learning is characterized by an initial association learning phase, followed by habit learning. While the effects of cannabinoids on habit learning have been well-studied, little is known about how cannabinoids influence the initial phase of reinforcement learning. RESULTS: We found that acute activation of cannabinoid receptor type 1 (CB1R) by the synthetic cannabinoid HU210 induced dose-dependent impairment of association learning, which could be alleviated by intra-dorsomedial striatum (DMS) injection of CB1R antagonist. Moreover, acute exposure to HU210 elicited enhanced synaptic transmission in striatonigral "direct" pathway medium spiny neurons (MSNs) but not indirect pathway neurons in DMS. Intriguingly, enhancement of synaptic transmission that is also observed after learning was abolished by HU210, indicating cannabinoid system might disrupt reinforcement learning by confounding synaptic plasticity normally required for learning. Remarkably, the impaired response-reinforcer learning was also induced by selectively enhancing the D1-MSN (MSN that selectively expresses the dopamine receptor type 1) activity by virally expressing excitatory hM3Dq DREADD (designer receptor exclusively activated by a designer drug), which could be rescued by specifically silencing the D1-MSN activity via hM4Di DREADD. CONCLUSION: Our findings demonstrate dose-dependent deleterious effects of cannabinoids on association learning by disrupting plasticity change required for learning associated with the striatal direct pathway, which furthers our understanding of the side-effects of cannabinoids and the underlying mechanisms.


Assuntos
Canabinoides , Aprendizagem por Associação , Canabinoides/metabolismo , Canabinoides/farmacologia , Corpo Estriado/metabolismo , Humanos , Neurônios/fisiologia , Transmissão Sináptica
12.
Eat Weight Disord ; 28(1): 47, 2023 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-37243772

RESUMO

OBJECTIVE: The rapid spread of the Omicron variant of COVID-19 in China had resulted in campus lockdown in many universities since February 2022, profoundly affecting students' daily lives. Campus lockdown conditions differ considerably from home quarantine, so that the eating patterns of university students may be different. Thus, the current study aimed to: (1) investigate university students' eating patterns during campus lockdown; (2) identify factors associated with their disordered eating. METHOD: An online survey about recent life changes, disordered eating, stress, depression, and anxiety was carried out from April 8th to May 16th, 2022. A total of 2541 responses from 29 provinces/cities of China were received. RESULTS: 2213 participants were included in the main analysis, and other 86 participants were analyzed separately as a subgroup due to their diagnosis of eating disorder. Participants who were undergoing campus lockdown (the lockdown group) showed less disordered eating than those who had never been in campus lockdown (the never-lockdown group), as well as those who had experienced campus lockdown before (the once-lockdown group). However, they perceived more stress and felt more depressed. Being female, higher BMI, gaining weight, increasing exercise, spending more time on social media, higher level of depression and anxiety were all related to disordered eating in the lockdown group. CONCLUSIONS: Disordered eating among Chinese university students was less prevalent during campus lockdown due to the strict and regular diet. However, there is a potential risk of "revenge eating" after campus lockdown ends. Thus, there should be further tracking and related prevention. LEVEL OF EVIDENCE: IV, uncontrolled trials without any interventions.


Assuntos
COVID-19 , Transtornos da Alimentação e da Ingestão de Alimentos , Humanos , Feminino , Masculino , COVID-19/prevenção & controle , SARS-CoV-2 , Universidades , Controle de Doenças Transmissíveis , Transtornos da Alimentação e da Ingestão de Alimentos/epidemiologia , Estudantes
13.
Angew Chem Int Ed Engl ; 62(51): e202312255, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-37921242

RESUMO

In nature, cytochrome c oxidases catalyze the 4e- oxygen reduction reaction (ORR) at the heme/Cu site, in which CuI is used to assist O2 activation. Because of the thermodynamic barrier to generate CuI , synthetic Fe-porphyrin/Cu complexes usually show moderate electrocatalytic ORR activity. We herein report on a Co-corrole/Co complex 1-Co for energy-efficient electrocatalytic ORR. By hanging a CoII ion over Co corrole, 1-Co realizes electrocatalytic 4e- ORR with a half-wave potential of 0.89 V versus RHE, which is outstanding among corrole-based electrocatalysts. Notably, 1-Co outperforms Co corrole hanged with CuII or ZnII . We revealed that the hanging CoII ion can provide an electron to improve O2 binding thermodynamically and dynamically, a function represented by the biological CuI ion of the heme/Cu site. This work is significant to present a remarkable ORR electrocatalyst and to show the vital role of a second-sphere redox-active metal ion in promoting O2 binding and activation.

14.
J Biol Chem ; 295(19): 6652-6664, 2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32209651

RESUMO

Assembled α-synuclein in nerve cells and glial cells is the defining pathological feature of neurodegenerative diseases called synucleinopathies. Seeds of α-synuclein can induce the assembly of monomeric protein. Here, we used sucrose gradient centrifugation and transiently transfected HEK 293T cells to identify the species of α-synuclein from the brains of homozygous, symptomatic mice transgenic for human mutant A53T α-synuclein (line M83) that seed aggregation. The most potent fractions contained Sarkosyl-insoluble assemblies enriched in filaments. We also analyzed six cases of idiopathic Parkinson's disease (PD), one case of familial PD, and six cases of multiple system atrophy (MSA) for their ability to induce α-synuclein aggregation. The MSA samples were more potent than those of idiopathic PD in seeding aggregation. We found that following sucrose gradient centrifugation, the most seed-competent fractions from PD and MSA brains are those that contain Sarkosyl-insoluble α-synuclein. The fractions differed between PD and MSA, consistent with the presence of distinct conformers of assembled α-synuclein in these different samples. We conclude that α-synuclein filaments are the main driving force for amplification and propagation of pathology in synucleinopathies.


Assuntos
Encéfalo/metabolismo , Sinucleinopatias/metabolismo , alfa-Sinucleína/química , alfa-Sinucleína/metabolismo , Animais , Encéfalo/patologia , Células HEK293 , Homozigoto , Humanos , Camundongos , Camundongos Transgênicos , Sinucleinopatias/genética , Sinucleinopatias/patologia
15.
Mol Psychiatry ; 25(5): 977-992, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31142818

RESUMO

Stressful life events induce abnormalities in emotional and cognitive behaviour. The endogenous opioid system plays an essential role in stress adaptation and coping strategies. In particular, the µ-opioid receptor (µR), one of the major opioid receptors, strongly influences memory processing in that alterations in µR signalling are associated with various neuropsychiatric disorders. However, it remains unclear whether µR signalling contributes to memory impairments induced by acute stress. Here, we utilized pharmacological methods and cell-type-selective/non-cell-type-selective µR depletion approaches combined with behavioural tests, biochemical analyses, and in vitro electrophysiological recordings to investigate the role of hippocampal µR signalling in memory-retrieval impairment induced by acute elevated platform (EP) stress in mice. Biochemical and molecular analyses revealed that hippocampal µRs were significantly activated during acute stress. Blockage of hippocampal µRs, non-selective deletion of µRs or selective deletion of µRs on GABAergic neurons (µRGABA) reversed EP-stress-induced impairment of memory retrieval, with no effect on the elevation of serum corticosterone after stress. Electrophysiological results demonstrated that stress depressed hippocampal GABAergic synaptic transmission to CA1 pyramidal neurons, thereby leading to excitation/inhibition (E/I) imbalance in a µRGABA-dependent manner. Pharmaceutically enhancing hippocampal GABAA receptor-mediated inhibitory currents in stressed mice restored their memory retrieval, whereas inhibiting those currents in the unstressed mice mimicked the stress-induced impairment of memory retrieval. Our findings reveal a novel pathway in which endogenous opioids recruited by acute stress predominantly activate µRGABA to depress GABAergic inhibitory effects on CA1 pyramidal neurons, which subsequently alters the E/I balance in the hippocampus and results in impairment of memory retrieval.


Assuntos
Neurônios GABAérgicos/metabolismo , Hipocampo/metabolismo , Hipocampo/patologia , Transtornos da Memória/etiologia , Transtornos da Memória/fisiopatologia , Receptores Opioides mu/metabolismo , Estresse Psicológico/complicações , Estresse Psicológico/fisiopatologia , Animais , Região CA1 Hipocampal/metabolismo , Região CA1 Hipocampal/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
16.
BMC Pediatr ; 21(1): 162, 2021 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-33827496

RESUMO

BACKGROUND: The implementation of early intervention (EI) in medical settings is time-consuming and resource-intensive, which limits its extensive use. In 2018, the Chinese Eugenics Association developed a home-based, post-discharge EI program. This study aims at evaluating the impact of this EI program on neurodevelopment and physical growth of early preterm infants. METHODS: This study was a prospective, partially blinded, randomized controlled trial (RCT), followed by an open phase. A total of 73 infants born at 28+ 0 ~ 31+ 6 weeks' gestation who were admitted to the Children's Hospital of Chongqing Medical University between December 1, 2019, and June 31, 2020, were enrolled. Another 33 infants were retrospectively recruited as the reference group. Thirty-seven infants randomized in the first early intervention, then standard care (EI-SC) group performed a 30-day EI during RCT period, while 36 infants allocated to SC-EI group were given EI in the following open phase. The test of infant motor performance (TIMP), development quotient (DQ), and anthropometric measures (length, weight, head circumference) were measured at the baseline (T0), termination of the RCT (T1), and termination of the open phase (T2). Repeated measures analysis was performed for comparison among groups. RESULTS: From T0 to T1, both groups had significant improvements in all outcome measures (all p < 0.001). A 30-day EI program was more effective in improving TIMP than standard care (from 53.12 ± 8.79 to 83.50 ± 11.85 in EI-SC group vs from 50.52 ± 8.64 to 75.97 ± 13.44 in SC-EI group, F = 4.232, p = 0.044). EI-SC group also had greater improvements in length, weight, and head circumference than SC-EI group (all p < 0.05). From T0 to T2, there was no significant difference regarding the improvements in all outcomes between the groups (all p > 0.05). At the endpoint of T2, the EI-SC and SC-EI group had similar TIMP and anthropometric measures, but much higher than the reference group (all p < 0.05). CONCLUSIONS: These findings demonstrated that a home-based, post-discharge EI program in this study was a practical approach to promote motor development and physical growth in early preterm infants. TRIAL REGISTRATION: CHICTR, CTR1900028330, registered December 19, 2019, https:// http://www.chictr.org.cn/showproj.aspx?proj=45706.


Assuntos
Intervenção Médica Precoce , Alta do Paciente , Criança , Intervenção Educacional Precoce , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro
17.
Plant Dis ; 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33406861

RESUMO

Plum is commercially cultivated worldwide for the rich nutrient in its fruit. In May 2019, plum with symptoms of fruit rot were collected from fields located in Liuma town, Guizhou Province, China. The incidence of the disease varied from 10 to 20%, which was observed in 15 plum orchards (18 hectares) surveyed. Estimated yield loss was~5 to 10% for each field. Diseased fruits showed deformity, wilting and sunken lesions, and subsequenly became melanized and rotted. Diseased tissues were surface disinfected with 70% ethanol for 45 s and rinsed with sterile distilled water three times. Four morphologically similar colonies with white fluffy aerial mycelium and a reddish pigment were obtained after 3 days incubation on potato dextrose agar (PDA) at 25°C. Four single-spore isolates produced conidia with 1 to 2 septa that were sickle-shaped, thin-walled with a tapering and curved apical cell, measuring 15.6 to 29.6 × 4.8 to 8.7 µm (average 19.5×5.9 µm, n=50). Based on the cultural and conidial morphology, the isolates were identified as Fusarium (Mun et al. 2012; Leslie and Summerell 2006). DNA of two isolates was extracted using the Ezup Column Fungal Genomic DNA Extraction Kit (Sangon Bioengineering Shanghai, LTD.). To confirm the morphological diagnosis, DNA sequence data from three loci were obtained. PCR amplification was carried out with universal primers ITS1/ITS4 (White et al. 1990), translation elongation factor (EF-1α), EF1-H (5'-ATGGGTAAGGAAGACAAGAC-3') and EF2-T (5'-GGAAGTACCAGTGATCATGTT-3') (O'Donnell et al. 1998) and the second largest subunit of RNA polymerase II (RPB2), 5F2(5'-GGGGWGAYCAGAAGAAGGC-3') and 7cR (5'-CCCATRGCTTGYTTRCCCAT-3') (O'Donnell et al. 2007). Primers ITS1 and ITS4 produced a 559-bp amplicon (GenBank accession. MW085028). BLAST analysis showed 100% sequence identity to sequences of several species, deposited in GenBank, including F. fujikuroi. The EF-1α sequence (MW086868) was 100% identical to that of Fusarium fujikuroi (MN193860.1). The RPB2 primers amplified a fragment (MW086869) that was 99.9% identical to that of F. fujikuroi (MN193888.1). The BLASTn results based on the partial EF-1α and RPB2 sequences suggest isolate HJGF1 is F. fujikuroi. A pathogenicity assay was conducted using an agar disk inoculation method on plum. Fruits were stab inoculated with HJGF1 by piercing 1-mm at 3 points using a sterile needle, and fruits were mock inoculated with sterile PDA, each fruit was inoculated with three disks. (Fig. 1). The treated fruit were maintained in a growth chamber with 90% relative humidity at 25°C, and a daily 12-h photoperiod. After 5 days, the artificially inoculated fruit showed blotches with sunken lesions similar to those observed in the orchards, whereas no symptoms were observed on the control fruit. The experiment was repeated twice with similar results. F. fujikuroi was reisolated from infected tissues and confirmed by sequence analysis. To our knowledge, this is the first report of F. fujikuroi causing fruit blotch of plum in China. Considering the economic importance of plum in China and throughout the world, F. fujikuroi may be an emerging problem for plum cultivation. Thus, further study of fruit blotch of plum is warranted.

18.
Cancer Control ; 27(1): 1073274820922553, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32420748

RESUMO

Vascular endothelial growth factor (VEGF) and its receptor (VEGFR) are highly expressed in nasopharyngeal carcinoma; therefore, blocking the binding of VEGF and VEGFR may be a potential way to treat nasopharyngeal carcinoma. Apatinib inhibits tumor angiogenesis. Previous studies have suggested that treatment with apatinib has an antitumor effect on nasopharyngeal carcinoma. This study will investigate the effect of apatinib combined with radiotherapy. In this study, nude mice injected with CNE-2 nasopharyngeal carcinoma cells were randomly divided into 6 groups. Therapeutic effects were assessed by evaluating tumor inhibition rate, phosphorylation of VEGFR-2, CD31, partial oxygen pressure, and tumor metabolism. We found that the tumor inhibition of mice in the treated groups was better compared to that of the control group. In mice treated with apatinib alone, angiogenesis was prevented, and the tumor tissue partial oxygen pressure was reduced, thereby achieving an antitumor effect. Moreover, the tumor inhibitory effect of combined treatment was stronger than treatment with either apatinib or radiotherapy alone. Compared with monotherapy treatment, combined treatment better resisted angiogenesis. Apatinib combined with radiotherapy to treat nasopharyngeal carcinoma has synergistic effects, which may be related to enhanced antiangiogenesis.


Assuntos
Quimiorradioterapia/métodos , Carcinoma Nasofaríngeo/terapia , Piridinas/farmacologia , Animais , Feminino , Camundongos , Camundongos Nus , Fosforilação/efeitos dos fármacos , Molécula-1 de Adesão Celular Endotelial a Plaquetas/efeitos dos fármacos , Distribuição Aleatória , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/efeitos dos fármacos
19.
BMC Vet Res ; 16(1): 129, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32381017

RESUMO

BACKGROUND: Recombinant Salmonella enterica serotype Choleraesuis (S. Choleraesuis) vaccine vector could be used to deliver heterologous antigens to prevent and control pig diseases. We have previously shown that a live-attenuated S. Choleraesuis vaccine candidate strain rSC0011 (ΔPcrp527::TT araC PBADcrp Δpmi-2426 ΔrelA199::araC PBADlacI TT ΔasdA33, Δ, deletion, TT, terminator) delivering SaoA, a conserved surface protein in most of S. suis serotypes, provided excellent protection against S. suis challenge, but occasionally lead to morbidity (enteritidis) in vaccinated mice (approximately 1 in every 10 mice). Thus, alternated attenuation method was sought to reduce the reactogenicity of strain rSC0011. Herein, we described another recombinant attenuated S. Choleraesuis vector, rSC0012 (ΔPfur88:: TT araC PBADfur Δpmi-2426 ΔrelA199:: araC PBADlacI TT ΔasdA33) with regulated delayed fur mutation to avoid inducing disease symptoms while exhibiting a high degree of immunogenicity. RESULTS: The strain rSC0012 strain with the ΔPfur88::TT araC PBADfur mutation induced less production of inflammatory cytokines than strain rSC0011 with the ΔPcrp527::TT araC PBADcrp mutation in mice. When delivering the same pS-SaoA plasmid, the intraperitoneal LD50 of rSC0012 was 18.2 times higher than that of rSC0011 in 3-week-old BALB/C mice. rSC0012 with either pS-SaoA or pYA3493 was cleared from spleen and liver tissues 7 days earlier than rSC0011 with same vectors after oral inoculation. The strain rSC0012 synthesizing SaoA induced high titers of anti-SaoA antibodies in both systemic (IgG in serum) and mucosal (IgA in vaginal washes) sites, as well as increased level of IL-4, the facilitator of Th2-type T cell immune response in mice. The recombinant vaccine rSC0012(pS-SaoA) conferred high percentage of protection against S. suis or S. Choleraesuis challenge in BALB/C mice. CONCLUSIONS: The live-attenuated Salmonella enterica serotype Choleraesuis vaccine rSC0012(pS-SaoA) with regulated delayed fur mutation provides a foundation for the development of a safe and effective vaccine against S. Choleraesuis and S. suis.


Assuntos
Salmonella enterica/genética , Infecções Estreptocócicas/imunologia , Streptococcus suis/imunologia , Animais , Feminino , Camundongos Endogâmicos BALB C , Mutação , Vacinas contra Salmonella/efeitos adversos , Vacinas contra Salmonella/genética , Vacinas contra Salmonella/imunologia , Sorogrupo , Streptococcus suis/genética , Vacinas Atenuadas/efeitos adversos , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia , Vacinas Sintéticas/efeitos adversos , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia
20.
Oral Dis ; 26(7): 1576-1585, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32352617

RESUMO

OBJECTIVE: The present case-control study aimed to compare the psychological status of patients with and without halitosis, and investigate the association between psychological disorders and halitosis. METHODS: Patients who complained about bad breath and diagnosed with genuine halitosis were assigned to the halitosis group, while patients without genuine halitosis were assigned to the control group (n = 106, each group). Information on the demographics and Symptom Checklist-90 (SCL-90) of participants was collected. The organoleptic score and Halimeter measurement were used to measure halitosis. RESULTS: The mean SCL-90 score of participants in the halitosis group (0.63) was significantly greater than that in the control group (0.48) (p = .002). The scores of the domains of interpersonal sensitivity, anxiety, depression, and paranoid ideation were found to be significantly different between the two groups (p < .05). However, there were no significant differences in SCL-90 scores between the mild and moderate-severe halitosis groups (p = .479). CONCLUSION: The psychological status of genuine halitosis patients was significantly worse than normal patients without halitosis complaint and also without halitosis. The main problems were in the aspects of interpersonal sensitivity, anxiety, depression, and paranoia. However, the negative impact was not related to the severity of halitosis.


Assuntos
Halitose , Ansiedade , Povo Asiático , Estudos de Casos e Controles , Halitose/etiologia , Humanos , Inquéritos e Questionários
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