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Diabetic wounds are serious clinical complications which manifest wet condition due to the mass exudate, along with disturbed regulation of inflammation, severe oxidative stress and repetitive bacterial infection. Existing treatments for diabetic wounds remain unsatisfactory due to the lack of ideal dressings that encompass mechanical performance, adherence to moist tissue surfaces, quick repair, and diverse therapeutic benefits. Herein, we fabricated a wet adhesive, self-healing, glucose-responsive drug releasing hydrogel with efficient antimicrobial and pro-healing properties for diabetic wound treatment. PAE hydrogel was constructed with poly(acrylic acid-co-acrylamide) (AA-Am) integrated with a dynamic E-F crosslinker, which consisted of epigallocatechin gallate (EGCG) and 4-(2-acrylamidoethylcarbamoyl)-3-fluorophenylboronic acid (AFPBA). Due to the dynamic crosslinking nature of boronate esters, abundant catechol groups and hydrogen bonding, PAE hydrogel demonstrated excellent mechanical properties with about 1000 % elongation, robust adhesion to moist tissues, fast self-healing, and absorption of biofluids of 10 times of its own weight. Importantly, PAE hydrogel exhibited sustained and glucose-responsive release of EGCG. Together, the bioactive PAE hydrogel had effective antibacterial, antioxidative, and anti-inflammatory properties in vitro, and accelerated diabetic wound healing in rats via reducing tissue-inflammatory response, enhancing angiogenesis, and reprogramming of macrophages. Overall, this versatile hydrogel provides a straightforward solution for the treatment of diabetic wound, and shows potential for other wound-related application scenarios.
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P-stereogenic phosphines, renowned for their utility as ligands and catalysts, have been instrumental in the field of asymmetric catalysis. However, the catalytic asymmetric synthesis of chiral ligands possessing both axial and phosphine chirality remains a significant challenge. Here, we present the successful demonstration of a Cu-catalyzed asymmetric C-P construction using in situ generated secondary phosphine and heteroaryl chloride. By introducing a chiral NHC ligand and an achiral diphosphine auxiliary ligand, we effectively alleviated the poisoning effect caused by phosphine(III) compounds and suppressed the nonenantioselective background reaction. The reaction exhibited excellent enantioselectivity, with up to 96% ee, and good diastereoselectivity, with up to 14:1 dr, when employing less sterically hindered secondary phosphines. This particular substrate poses a significant challenge due to its strong poisoning effect in copper catalysis.
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Efficient removal and recovery of phosphorus from aquaculture tailwater is challenging due to increasing strict water environment restrictions. This study presents a sustainable approach by using microalgae-waste-derived hydrogels/membranes for phosphorus adsorption and microalgae cultivation. Waste from Euglena gracilis (or Haematococcus pluvialis), modified with magnesium, was converted into biochars (abbreviated as MEBC or MHBC). This biochars were then combined with sodium alginate to fabricate hydrogels and with polyvinyl chloride to create membranes. Due to the almost 100 % phosphorus removal of MEBC (or MHBC) biochar, the as-obtained hydrogels/membranes demonstrated excellent phosphate adsorption, reducing total phosphorus in real aquaculture tailwater from 11 mg/L to 0. Additionally, the phosphorus-saturated hydrogel served as a phosphorus source for microalgae cultivation, while the membranes facilitated microalgae harvesting with a water flux over 40 L/m2/h. This study provides an eco-friendly solution for using microalgae-waste-derived materials to effectively address phosphorus removal and recovery challenges in aquaculture tailwater.
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AIM: To identify latent profiles of narrative competence in nursing students and examine the association between the potential competence profiles and professional identity from a person-centred perspective. BACKGROUND: According to the Ring theory of personhood, nursing students can develop their professional identities from individual, relational and social aspects through interaction with patients, as well as listening to, understanding and responding to patients' disease narratives. However, few studies have examined the relationship between narrative competence and professional identity through the quantitative method. DESIGN: A cross-sectional analytic study. METHODS: A total of 472 nursing students responded to the survey between March and May 2023. The Professional Identity Questionnaire for Nurse Students and the Narrative Competence Scale were given to participants. Latent profile analysis was conducted to identify narrative competence profiles. The Bolck-Croon-Hagenaars method was used to analyse whether these latent profiles for narrative competence affected nursing students' general, individual, interpersonal and social professional identities. RESULTS: Latent profiles were identified as "low narrative competence" (12.1â¯%), "relatively low narrative competence" (39.9â¯%), "moderate narrative competence" (40.1â¯%) and "high narrative competence" (7.9â¯%). The profiles only show level differences rather than combinations of competence areas. These profiles had varying effects on the nursing students' general professional identities, as well as their individual, relational and social professional identities. CONCLUSION: This study highlights the significance of providing tailored guidance and support to nursing students, taking into account their unique narrative competency profile, to promote the formation of professional identity from individual, relational and social aspects. Nursing educators should effectively distinguish nursing students with inadequate narrative competence and value patients' disease narratives to promote narrative competence and professional identity.
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BACKGROUND: Individuals with schizophrenia tend to have negative coping styles and low levels of self-esteem, but it is unclear whether coping styles and self-esteem levels are altered in people in the prodromal phase of psychosis. AIMS: The study was designed to assess the role of coping style and self-esteem in the context of different phases of schizophrenia. METHODS: Recurrent Schizophrenia (ReSch), first-episode schizophrenia patients (FEP), genetic-high risk for psychosis (GHR) patients, and healthy controls (HC) (40 per group) were subjected to in-person clinical interviews. The results of these interviews were then used to gauge coping style and self-esteem using the Coping Styles Questionnaire (CSQ) and the Rosenberg's Self-Esteem Scale (RSES). Data were analyzed through ANCOVAs and logistic regression analyses. RESULTS: The results found that positive coping style (CSQ problem-solving and CSQ seeking for help) generally decline with progression through the HC, GHR, and FEP groups, while negative coping style (CSQ fantasy, CSQ repression and CSQ self-blame) generally increase with progression through the HC, GHR, and FEP groups (except that GHR group was slightly lower than HC group in CSQ self-blame). Results for members of ReSch group were in line with those of members of the FEP group in coping style. At the level of self-esteem, the GHR group was similar to the HC group and significantly higher than the FEP group and the ReSch group. Logistic regression analyses indicated that GHR group patients exhibited increased negative coping styles (CSQ fantasy) relative to members of the HC group, but had greater Positive coping style (CSQ problem-solving) than did members of the FEP group. DISCUSSION: These findings suggest that both GHR individuals experience impaired negative coping styles which expands the understanding of the psychological characteristics of the prodromal group. Further explorations are warranted to develop optimal psychosocial interventions.
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Intrinsic plasticity, a fundamental process enabling neurons to modify their intrinsic properties, plays a crucial role in shaping neuronal input-output function and is implicated in various neurological and psychiatric disorders. Despite its importance, the underlying molecular mechanisms of intrinsic plasticity remain poorly understood. In this study, a new ubiquitin ligase adaptor, protein tyrosine phosphatase receptor type N (PTPRN), is identified as a regulator of intrinsic neuronal excitability in the context of temporal lobe epilepsy. PTPRN recruits the NEDD4 Like E3 Ubiquitin Protein Ligase (NEDD4L) to NaV1.2 sodium channels, facilitating NEDD4L-mediated ubiquitination, and endocytosis of NaV1.2. Knockout of PTPRN in hippocampal granule cells leads to augmented NaV1.2-mediated sodium currents and higher intrinsic excitability, resulting in increased seizure susceptibility in transgenic mice. Conversely, adeno-associated virus-mediated delivery of PTPRN in the dentate gyrus region decreases intrinsic excitability and reduces seizure susceptibility. Moreover, the present findings indicate that PTPRN exerts a selective modulation effect on voltage-gated sodium channels. Collectively, PTPRN plays a significant role in regulating intrinsic excitability and seizure susceptibility, suggesting a potential strategy for precise modulation of NaV1.2 channels' function.
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Endocitose , Convulsões , Animais , Camundongos , Convulsões/metabolismo , Convulsões/genética , Endocitose/fisiologia , Endocitose/genética , Camundongos Transgênicos , Modelos Animais de Doenças , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Masculino , Camundongos KnockoutRESUMO
Background: During the acute heart failure (AHF), acute kidney injury (AKI) is highly prevalent in critically ill patients. The occurrence of the latter condition increases the risk of mortality in patients with acute heart failure. The current research on the relationship between nutritional risk and the occurrence of acute kidney injury in patients with acute heart failure is very limited. Methods: This retrospective cohort study utilized data from the Medical Information Mart for Intensive Care IV (MIMIC-IV, version 2.1) database. We included adult patients with AHF who were admitted to the intensive care unit in the study. Results: A total of 1310 critically ill patients with acute heart failure were included. The AUC of geriatric nutritional risk index (GNRI) (0.694) is slightly superior to that of controlling nutritional status (CONUT) (0.656) and prognostic nutritional index (PNI) (0.669). The Log-rank test revealed a higher risk of acute kidney injury in patients with high nutritional risk (p < 0.001). Multivariate COX regression analysis indicated that a high GNRI (adjusted HR 0.62, p < 0.001) was associated with a reduced risk of AKI during hospitalization in AHF patients. The final subgroup analysis demonstrated no significant interaction of GNRI in all subgroups except for diabetes subgroup and ventilation subgroup (P for interaction: 0.057-0.785). Conclusion: Our study findings suggest a correlation between GNRI and the occurrence of acute kidney injury in patients hospitalized with acute heart failure.
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Injúria Renal Aguda , Estado Terminal , Insuficiência Cardíaca , Unidades de Terapia Intensiva , Avaliação Nutricional , Estado Nutricional , Humanos , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/complicações , Feminino , Masculino , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Estudos Retrospectivos , Idoso , Unidades de Terapia Intensiva/estatística & dados numéricos , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Fatores de Risco , Medição de Risco , Avaliação Geriátrica , Prognóstico , Modelos de Riscos ProporcionaisRESUMO
RATIONALE: Paraneoplastic neurological syndrome with anti-Hu antibody (Hu-PNS) is a neurological disorder that occur in patients with malignancy. The syndrome has a wide range of presentations and can present before diagnosis of primary malignancy. Familiarity with these paraneoplastic neurological syndromes can help early recognition and take appropriate regimens. PATIENTS CONCERNS: Diagnosis and treatment of Hu-PNS. DIAGNOSES: This is retrospective study that analyzed the clinical data of this case. Through retrospective analysis and targeted antibody screening, serum anti-Hu antibody was detected. Subsequent spinal imaging revealed a mass in the paraspinal region, which was confirmed as ganglioneuroblastoma by pathologic examination. INTERVENTIONS: The child was treated with a course of intravenous immunoglobulin and radical surgical operation without chemotherapy. OUTCOMES: The neurological symptoms were gradually improved and no signs indicate disease progression or tumor recurrence. LESSONS: Hu-PNS has rarely been reported in children with ganglioneuroblastomas. They can mimic non-neoplastic processes, making detection and diagnosis difficult. Serum and/or cerebrospinal fluid onconeural antibody can strongly indicate occult cancers. Early detection of paraneoplastic neurological syndromes can help take appropriate regimens and improve prognosis.
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Ganglioneuroblastoma , Síndromes Paraneoplásicas do Sistema Nervoso , Humanos , Ganglioneuroblastoma/imunologia , Ganglioneuroblastoma/complicações , Síndromes Paraneoplásicas do Sistema Nervoso/imunologia , Síndromes Paraneoplásicas do Sistema Nervoso/diagnóstico , Masculino , Proteínas ELAV/imunologia , Autoanticorpos/sangue , Autoanticorpos/imunologia , Pré-Escolar , Estudos RetrospectivosRESUMO
BACKGROUND: Although ultra-high risk for schizophrenia (UHR) is related to both genetic and environment factors, the precise pathogenesis is still unknow. To date, few studies have explored the Genome-Wide Association Studies (GWAS) in UHR or HR individuals especially in Han population in China. METHODS: In this study, a GWAS analysis for 36 participants with UHR and 43 with HR were performed, and all deletion variations in 22q11 region were also compared. RESULTS: Sixteen individuals with UHR (44.4%) and none with HR converted into schizophrenia in follow-up after two years. Six loci including neurexin-1(NRXN1) (rs1045881), dopamine D1 receptor (DRD1) (rs686, rs4532), chitinase-3-like protein 1 (CHI3L1) (rs4950928), velocardiofacial syndrome (ARVCF) (rs165815), dopamine D2 receptor (DRD2) (rs1076560) were identified higher expression with significant difference in individuals converted into schizophrenia after two years. The Family with Sequence Similarity 230 Member H (FAM230H) gene in the 22q11 region were also found high expression in UHR group. CONCLUSIONS: Further expansion of sample size and validation studies are needed to explore the pathogenesis of these risk loci in UHR conversion into schizophrenia in the future.
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Estudo de Associação Genômica Ampla , Esquizofrenia , Humanos , Esquizofrenia/genética , Feminino , Masculino , China , Adulto , Seguimentos , Adulto Jovem , Predisposição Genética para Doença/genética , Povo Asiático/genética , População do Leste AsiáticoRESUMO
Voltage-gated sodium (NaV) channels mediate a plethora of electrical activities. NaV channels govern cellular excitability in response to depolarizing stimuli. Inactivation is an intrinsic property of NaV channels that regulates cellular excitability by controlling the channel availability. The fast inactivation, mediated by the Ile-Phe-Met (IFM) motif and the N-terminal helix (N-helix), has been well-characterized. However, the molecular mechanism underlying NaV channel slow inactivation remains elusive. Here, we demonstrate that the removal of the N-helix of NaVEh (NaVEhΔN) results in a slow-inactivated channel, and present cryo-EM structure of NaVEhΔN in a potential slow-inactivated state. The structure features a closed activation gate and a dilated selectivity filter (SF), indicating that the upper SF and the inner gate could serve as a gate for slow inactivation. In comparison to the NaVEh structure, NaVEhΔN undergoes marked conformational shifts on the intracellular side. Together, our results provide important mechanistic insights into NaV channel slow inactivation.
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Microscopia Crioeletrônica , Ativação do Canal Iônico , Canais de Sódio Disparados por Voltagem , Canais de Sódio Disparados por Voltagem/metabolismo , Canais de Sódio Disparados por Voltagem/química , Humanos , Animais , Células HEK293 , Modelos MolecularesRESUMO
Late sodium current (INa) inhibitors are a new subclass of antiarrhythmic agents. To overcome the drawbacks, e.g., low efficacy and inhibition effect on K+ current, of the FDA-approved late INa inhibitor ranolazine, chain amide 6a-6q, 1,4-disubstituted piperazin-2-ones 7a-7s, and their derivatives 8a-8n were successively designed, synthesized, and evaluated in vitro on the NaV1.5-transfected HEK293T cells by the whole-cell patch clamp recording assay at the concentration of 40 µM. Among the new skeleton compounds, 7d showed the highest efficacy (IC50 = 2.7 µM) and good selectivity (peak/late ratio >30 folds), as well as excellent pharmacokinetics properties in mice (T1/2 of 3.5 h, F = 90%, 3 mg/kg, po). It exhibited low hERG inhibition and was able to reverse the ATX-II-induced augmentation of late INa phenotype of LQT3 model in isolated rabbit hearts. These results suggest the application potentials of 7d in the treatments of arrhythmias related to the enhancement of late INa.
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Piperazinas , Animais , Coelhos , Células HEK293 , Humanos , Piperazinas/farmacologia , Piperazinas/química , Piperazinas/síntese química , Piperazinas/farmacocinética , Antiarrítmicos/farmacologia , Antiarrítmicos/química , Antiarrítmicos/farmacocinética , Antiarrítmicos/síntese química , Bloqueadores dos Canais de Sódio/farmacologia , Bloqueadores dos Canais de Sódio/química , Bloqueadores dos Canais de Sódio/síntese química , Bloqueadores dos Canais de Sódio/farmacocinética , Camundongos , Síndrome do QT Longo/induzido quimicamente , Relação Estrutura-Atividade , Masculino , Canal de Sódio Disparado por Voltagem NAV1.5/metabolismo , Coração/efeitos dos fármacos , Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Canais de Potássio Éter-A-Go-Go/metabolismo , Canal de Potássio ERG1/antagonistas & inibidores , Canal de Potássio ERG1/metabolismo , Doença do Sistema de Condução CardíacoRESUMO
Purpose: Exosomes are important "messengers" in cell-cell interactions, but their potential effects on palatal fusion are still unknown. This study aimed to explore the role and mechanism of exosomes derived from palatal mesenchymal cells in epithelial-mesenchymal communication during palatogenesis. Methods: The expression of exosome marker CD63 and CD81 in palatal cells during palatogenesis was detected by immunofluorescence staining. After being purified from the supernatant of human embryonic palatal mesenchymal (HEPM) cells, exosomes (HEPM-EXO) were characterized by nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM) and Western blot. HEPM-EXO were co-cultured with human immortalized oral epithelial cells (HIOEC). The effects of HEPM-EXO on the cell proliferation, migration, apoptosis and epithelial-mesenchymal transition (EMT) of HIOEC were evaluated. The proteins encapsulated in HEPM-EXO were analyzed by proteomic analysis. Results: The extensive expression of CD63 and CD81 in palatal epithelial and mesenchymal cells were continuously detected during E12.5~E14.5, suggesting that exosomes were involved in the process of palatal fusion. The expression of CD63 was also observed in the acellular basement membrane between the palatal epithelium and the mesenchyme in vivo, and HEPM-EXO could be internalized by HIOEC in vitro, suggesting that exosomes are potent to diffuse through the cellular tissue boundary to mediate palatal cell-cell communication. Exposure of HEPM-EXO to HIOEC substantially inhibited the proliferation and stimulated the migration of HIOEC, but had no significant effect on cell apoptosis and EMT. Proteomic analysis revealed the basic characteristics of the proteins in HEPM-EXO and that exosomal THBS1 may potentially regulate the cell behaviors of HIOEC, which needs further verification. Gene ontology (GO) analysis uncovered that the proteins highly expressed in HEPM-EXO are closely related to wound healing, implying a promising therapeutic opportunity of HEPM-EXO in tissue injury treatment with future studies. Conclusion: HEPM-EXO mediated cell-cell communication by regulating cell proliferation and migration of oral epithelial cells during palatogenesis.
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Exossomos , Humanos , Exossomos/metabolismo , Proteômica , Comunicação Celular , Células Epiteliais , CicatrizaçãoRESUMO
The nonselective calcium-permeable Transient Receptor Potential Cation Channel Subfamily V Member4 (TRPV4) channel regulates various physiological activities. Dysfunction of TRPV4 is linked to many severe diseases, including edema, pain, gastrointestinal disorders, lung diseases, and inherited neurodegeneration. Emerging TRPV4 antagonists show potential clinical benefits. However, the molecular mechanisms of TRPV4 antagonism remain poorly understood. Here, cryo-electron microscopy (cryo-EM) structures of human TRPV4 are presented in-complex with two potent antagonists, revealing the detailed binding pockets and regulatory mechanisms of TRPV4 gating. Both antagonists bind to the voltage-sensing-like domain (VSLD) and stabilize the channel in closed states. These two antagonists induce TRPV4 to undergo an apparent fourfold to twofold symmetry transition. Moreover, it is demonstrated that one of the antagonists binds to the VSLD extended pocket, which differs from the canonical VSLD pocket. Complemented with functional and molecular dynamics simulation results, this study provides crucial mechanistic insights into TRPV4 regulation by small-molecule antagonists, which may facilitate future drug discovery targeting TRPV4.
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Microscopia Crioeletrônica , Canais de Cátion TRPV , Canais de Cátion TRPV/antagonistas & inibidores , Canais de Cátion TRPV/metabolismo , Canais de Cátion TRPV/química , Canais de Cátion TRPV/genética , Humanos , Microscopia Crioeletrônica/métodos , Simulação de Dinâmica Molecular , Sítios de LigaçãoRESUMO
Intestinal macrophages play crucial roles in both intestinal inflammation and immune homeostasis. They can adopt two distinct phenotypes, primarily determined by environmental cues. These phenotypes encompass the classically activated pro-inflammatory M1 phenotype, as well as the alternatively activated anti-inflammatory M2 phenotype. In regular conditions, intestinal macrophages serve to shield the gut from inflammatory harm. However, when a combination of genetic and environmental elements influences the polarization of these macrophages, it can result in an M1/M2 macrophage activation imbalance, subsequently leading to a loss of control over intestinal inflammation. This shift transforms normal inflammatory responses into pathological damage within the intestines. In patients with ulcerative colitis-associated colorectal cancer (UC-CRC), disorders related to intestinal inflammation are closely correlated with an imbalance in the polarization of intestinal M1/M2 macrophages. Therefore, reinstating the equilibrium in M1/M2 macrophage polarization could potentially serve as an effective approach to the prevention and treatment of UC-CRC. This paper aims to scrutinize the clinical evidence regarding Chinese medicine (CM) in the treatment of UC-CRC, the pivotal role of macrophage polarization in UC-CRC pathogenesis, and the potential mechanisms through which CM regulates macrophage polarization to address UC-CRC. Our objective is to offer fresh perspectives for clinical application, fundamental research, and pharmaceutical advancement in UC-CRC.
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Neoplasias Associadas a Colite , Progressão da Doença , Macrófagos , Humanos , Macrófagos/patologia , Neoplasias Associadas a Colite/patologia , Neoplasias Associadas a Colite/tratamento farmacológico , Neoplasias Colorretais/patologia , Animais , Colite Ulcerativa/patologia , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/complicaçõesRESUMO
Increased cortisol levels in the preovulatory follicular fluid suggests a role of glucocorticoid in human ovulation. However, the mechanisms through which cortisol regulates the ovulatory process remain poorly understood. In this study, we examined the upregulation of f5 mRNA by glucocorticoid and its receptor (Gr) in the preovulatory follicles of zebrafish. Our findings demonstrate a significant increase in 11ß-hydroxysteroid dehydrogenase type 2 (hsd11b2), a cortisol response gene, in preovulatory follicles. Additionally, hydrocortisone exerts a dose- and time-dependent upregulation of f5 mRNA in these follicles. Importantly, this stimulatory effect is Gr-dependent, as it was completely abolished in gr-/- mutants. Furthermore, site-directed mutagenesis identified a glucocorticoid response element (GRE) in the promoter of zebrafish f5. Interestingly, successive incubation of hydrocortisone and the native ovulation-inducing steroid, progestin (17α,20ß-dihydroxy-4-pregnen-3-one, DHP), further enhanced f5 expression in preovulatory follicles. Overall, our results indicate that the dramatic increase of f5 expression in preovulatory follicles is partially attributable to the regulation of glucocorticoid and Gr.
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Glucocorticoides , Hidrocortisona , Folículo Ovariano , Receptores de Glucocorticoides , Regulação para Cima , Peixe-Zebra , Animais , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Folículo Ovariano/metabolismo , Folículo Ovariano/efeitos dos fármacos , Feminino , Glucocorticoides/farmacologia , Regulação para Cima/efeitos dos fármacos , Receptores de Glucocorticoides/metabolismo , Receptores de Glucocorticoides/genética , Hidrocortisona/farmacologia , Hidrocortisona/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Ovulação/efeitos dos fármacos , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2/metabolismo , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2/genética , Regiões Promotoras GenéticasRESUMO
Biological soil crusts are of great significance for environment health and sustainable development in arid and semi-arid areas. Cyanobacteria, Microcoleus vaginatus, Scytonema sp., Nostoc sp., and Anabaena sp. are the dominant species in microbial community of biological soil crusts worldwide. Considering their broad application prospect, it is meaningful to cultivate them extensively. We examined the effects of temperature (10, 20, 25, 30, 35 â) and initial pH (4, 6, 8, 10, 12) on biomass and solution pH towards the four species of cyanobacteria with liquid culture in laboratory. The results showed that the biomass of the four cyanobacterial species grew slowly under 20 â, and that all species could grow in 25-35 â, with the highest growth rate at 25 and 30 â. The optimum culture temperature of different cyanobacterial species was slightly different. The optimum culture temperature was 25-30 â for Scytonema sp. and Nostoc sp., and 30 â for M. vaginatus and Anabaena sp. The four cyanobacterial species had a strong ability to adjust solution pH and proliferate in five different initial pH conditions. The highest maximum biomass and specific growth rate were recorded in the culture environment with initial pH of 4, while the lowest maximum biomass and specific growth rate were observed in initial pH of 12. Our results would provide scientific basis for the propagation of dominant cyanobacteria in biological soil crusts.
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Cianobactérias , Clima Desértico , Temperatura , Solo , Concentração de Íons de Hidrogênio , Microbiologia do SoloRESUMO
The voltage-gated calcium channel CaV1.2 is essential for cardiac and vessel smooth muscle contractility and brain function. Accumulating evidence demonstrates that malfunctions of CaV1.2 are involved in brain and heart diseases. Pharmacological inhibition of CaV1.2 is therefore of therapeutic value. Here, we report cryo-EM structures of CaV1.2 in the absence or presence of the antirheumatic drug tetrandrine or antihypertensive drug benidipine. Tetrandrine acts as a pore blocker in a pocket composed of S6II, S6III, and S6IV helices and forms extensive hydrophobic interactions with CaV1.2. Our structure elucidates that benidipine is located in the DIII-DIV fenestration site. Its hydrophobic sidechain, phenylpiperidine, is positioned at the exterior of the pore domain and cradled within a hydrophobic pocket formed by S5DIII, S6DIII, and S6DIV helices, providing additional interactions to exert inhibitory effects on both L-type and T-type voltage gated calcium channels. These findings provide the structural foundation for the rational design and optimization of therapeutic inhibitors of voltage-gated calcium channels.
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Canais de Cálcio Tipo L , Canais de Cálcio Tipo L/metabolismo , Estrutura Secundária de ProteínaRESUMO
Epileptogenesis, arising from alterations in synaptic strength, shares mechanistic and phenotypic parallels with memory formation. However, direct evidence supporting the existence of seizure memory remains scarce. Leveraging a conditioned seizure memory (CSM) paradigm, we found that CSM enabled the environmental cue to trigger seizure repetitively, and activating cue-responding engram cells could generate CSM artificially. Moreover, cue exposure initiated an analogous process of memory reconsolidation driven by mammalian target of rapamycin-brain-derived neurotrophic factor signaling. Pharmacological targeting of the mammalian target of rapamycin pathway within a limited time window reduced seizures in animals and interictal epileptiform discharges in patients with refractory seizures. Our findings reveal a causal link between seizure memory engrams and seizures, which leads us to a deeper understanding of epileptogenesis and points to a promising direction for epilepsy treatment.
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Eletroencefalografia , Epilepsia , Animais , Humanos , Convulsões/etiologia , Sirolimo , Serina-Treonina Quinases TOR , MamíferosRESUMO
Identifying drug-protein interactions (DPIs) is crucial in drug discovery and repurposing. Computational methods for precise DPI identification can expedite development timelines and reduce expenses compared with conventional experimental methods. Lately, deep learning techniques have been employed for predicting DPIs, enhancing these processes. Nevertheless, the limitations observed in prior studies, where many extract features from complete drug and protein entities, overlooking the crucial theoretical foundation that pharmacological responses are often correlated with specific substructures, can lead to poor predictive performance. Furthermore, certain substructure-focused research confines its exploration to a solitary fragment category, such as a functional group. In this study, addressing these constraints, we present an end-to-end framework termed BCMMDA for predicting DPIs. The framework considers various substructure types, including branch chains, common substructures, and specific fragments. We designed a specific feature learning module by combining our proposed multi-dimensional attention mechanism with convolutional neural networks (CNNs). Deep CNNs assist in capturing the synergistic effects among these fragment sets, enabling the extraction of relevant features of drugs and proteins. Meanwhile, the multi-dimensional attention mechanism refines the relationship between drug and protein features by assigning attention vectors to each drug compound and amino acid. This mechanism empowers the model to further concentrate on pivotal substructures and elements, thereby improving its ability to identify essential interactions in DPI prediction. We evaluated the performance of BCMMDA on four well-known benchmark datasets. The results indicated that BCMMDA outperformed state-of-the-art baseline models, demonstrating significant improvement in performance.