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1.
Proc Natl Acad Sci U S A ; 121(25): e2322107121, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38857396

RESUMO

The photocatalytic CO2-to-CH4 conversion involves multiple consecutive proton-electron coupling transfer processes. Achieving high CH4 selectivity with satisfactory conversion efficiency remains challenging since the inefficient proton and electron delivery path results in sluggish proton-electron transfer kinetics. Herein, we propose the fabrication of atomically adjacent anion-cation vacancy as paired redox active sites that could maximally promote the proton- and electron-donating efficiency to simultaneously enhance the oxidation and reduction half-reactions, achieving higher photocatalytic CO2 reduction activity and CH4 selectivity. Taking TiO2 as a photocatalyst prototype, the operando electron paramagnetic resonance spectra, quasi in situ X-ray photoelectron spectroscopy measurements, and high-angle annular dark-field-scanning transmission electron microscopy image analysis prove that the VTi on TiO2 as initial sites can induce electron redistribution and facilitate the escape of the adjacent oxygen atom, thereby triggering the dynamic creation of atomically adjacent dual-vacancy sites during photocatalytic reactions. The dual-vacancy sites not only promote the proton- and electron-donating efficiency for CO2 activation and protonation but also modulate the coordination modes of surface-bound intermediate species, thus converting the endoergic protonation step to an exoergic reaction process and steering the CO2 reduction pathway toward CH4 production. As a result, these in situ created dual active sites enable nearly 100% CH4 selectivity and evolution rate of 19.4 µmol g-1 h-1, about 80 times higher than that of pristine TiO2. Thus, these insights into vacancy dynamics and structure-function relationship are valuable to atomic understanding and catalyst design for achieving highly selective catalysis.

2.
Proc Natl Acad Sci U S A ; 121(9): e2315956121, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38377201

RESUMO

Photo-catalytic CO2 reduction with perovskite quantum dots (QDs) shows potential for solar energy storage, but it encounters challenges due to the intricate multi-electron photoreduction processes and thermodynamic and kinetic obstacles associated with them. This study aimed to improve photo-catalytic performance by addressing surface barriers and utilizing multiple-exciton generation in perovskite QDs. A facile surface engineering method was employed, involving the grafting of ferrocene carboxylic acid (FCA) onto CsPbBr3 (CPB) QDs, to overcome limitations arising from restricted multiple-exciton dissociation and inefficient charge transfer dynamics. Kelvin Probe Force Microscopy and XPS spectral confirmed successfully creating an FCA-modulated microelectric field through the Cs active site, thus facilitating electron transfer, disrupting surface barrier energy, and promoting multi-exciton dissociations. Transient absorption spectroscopy showed enhanced charge transfer and reduced energy barriers, resulting in an impressive CO2-to-CO conversion rate of 132.8 µmol g-1 h-1 with 96.5% selectivity. The CPB-FCA catalyst exhibited four-cycle reusability and 72 h of long-term stability, marking a significant nine-fold improvement compared to pristine CPB (14.4 µmol g-1 h-1). These results provide insights into the influential role of FCA in regulating intramolecular charge transfer, enhancing multi-exciton dissociation, and improving CO2 photoreduction on CPB QDs. Furthermore, these findings offer valuable knowledge for controlling quantum-confined exciton dissociation to enhance CO2 photocatalysis.

3.
Genes Dev ; 33(23-24): 1739-1750, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31753914

RESUMO

Proliferating cells, typically considered "nonexcitable," nevertheless, exhibit regulation by bioelectric signals. Notably, voltage-gated sodium channels (VGSC) that are crucial for neuronal excitability are also found in progenitors and up-regulated in cancer. Here, we identify a role for VGSC in proliferation of Drosophila neuroblast (NB) lineages within the central nervous system. Loss of paralytic (para), the sole gene that encodes Drosophila VGSC, reduces neuroblast progeny cell number. The type II neuroblast lineages, featuring a population of transit-amplifying intermediate neural progenitors (INP) similar to that found in the developing human cortex, are particularly sensitive to para manipulation. Following a series of asymmetric divisions, INPs normally exit the cell cycle through a final symmetric division. Our data suggests that loss of Para induces apoptosis in this population, whereas overexpression leads to an increase in INPs and overall neuroblast progeny cell numbers. These effects are cell autonomous and depend on Para channel activity. Reduction of Para expression not only affects normal NB development, but also strongly suppresses brain tumor mass, implicating a role for Para in cancer progression. To our knowledge, our studies are the first to identify a role for VGSC in neural progenitor proliferation. Elucidating the contribution of VGSC in proliferation will advance our understanding of bioelectric signaling within development and disease states.


Assuntos
Proliferação de Células/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila/citologia , Drosophila/genética , Células-Tronco Neurais/citologia , Canais de Sódio/genética , Canais de Sódio/metabolismo , Animais , Apoptose , Contagem de Células , Linhagem da Célula/genética , Expressão Gênica , Técnicas de Silenciamento de Genes
4.
Proc Natl Acad Sci U S A ; 120(44): e2307320120, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37871220

RESUMO

The selective photocatalytic conversion of CO2 and H2O to high value-added C2H4 remains a great challenge, mainly attributed to the difficulties in C-C coupling of reaction intermediates and desorption of C2H4* intermediates from the catalyst surface. These two key issues can be simultaneously overcome by alloying Ag with Cu which gives enhanced activity to both reactions. Herein, we developed a facile stepwise photodeposition strategy to load Cu-Ag alloy sub-nanoclusters (ASNCs) on TiO2 for CO2 photoreduction to produce C2H4. The optimized catalyst exhibits a record-high C2H4 formation rate (1110.6 ± 82.5 µmol g-1 h-1) with selectivity of 49.1 ± 1.9%, which is an order-of-magnitude enhancement relative to current work for C2H4 photosynthesis. The in situ FT-IR spectra combined with DFT calculations reveal the synergistic effect of Cu and Ag in Cu-Ag ASNCs, which enable an excellent C-C coupling capability like Ag and promoted C2H4* desorption property like Cu, thus advancing the selective and efficient production of C2H4. The present work provides a deeper understanding on cluster chemistry and C-C coupling mechanism for CO2 reduction on ASNCs and develops a feasible strategy for photoreduction CO2 to C2 fuels or industrial feedstocks.

5.
Brain Behav Immun ; 119: 648-664, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38677623

RESUMO

The high prevalence of major depressive disorder (MDD) frequently imposes severe constraints on psychosocial functioning and detrimentally impacts overall well-being. Despite the growing interest in the hypothesis of mitochondrial dysfunction, the precise mechanistic underpinnings and therapeutic strategies remain unclear and require further investigation. In this study, an MDD model was established in mice using lipopolysaccharide (LPS). Our research findings demonstrated that LPS exposure induced depressive-like behaviors and disrupted mitophagy by diminishing the mitochondrial levels of PINK1/Parkin in the brains of mice. Furthermore, LPS exposure evoked the activation of the NLRP3 inflammasome, accompanied by a notable elevation in the concentrations of pro-inflammatory factors (TNF-α, IL-1ß, and IL-6). Additionally, neuronal apoptosis was stimulated through the JNK/p38 pathway. The administration of BGP-15 effectively nullified the impact of LPS, corresponding to the amelioration of depressive-like phenotypes and restoration of mitophagy, prevention of neuronal injury and inflammation, and suppression of reactive oxygen species (ROS)-mediated NLRP3 inflammasome activation. Furthermore, we elucidated the involvement of mitophagy in BGP-15-attenuated depressive-like behaviors using the inhibitors targeting autophagy (3-MA) and mitophagy (Mdivi-1). Notably, these inhibitors notably counteracted the antidepressant and anti-inflammatory effects exerted by BGP-15. Based on the research findings, it can be inferred that the antidepressant properties of BGP-15 in LPS-induced depressive-like behaviors could potentially be attributed to the involvement of the mitophagy pathway. These findings offer a potential novel therapeutic strategy for managing MDD.


Assuntos
Depressão , Inflamassomos , Lipopolissacarídeos , Mitocôndrias , Mitofagia , Proteína 3 que Contém Domínio de Pirina da Família NLR , Animais , Mitofagia/efeitos dos fármacos , Camundongos , Masculino , Inflamassomos/metabolismo , Inflamassomos/efeitos dos fármacos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Depressão/metabolismo , Depressão/tratamento farmacológico , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Espécies Reativas de Oxigênio/metabolismo , Modelos Animais de Doenças , Transtorno Depressivo Maior/metabolismo , Inflamação/metabolismo , Comportamento Animal/efeitos dos fármacos , Proteínas Quinases/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Furanos , Indenos , Sulfonamidas
6.
Reprod Biomed Online ; 49(2): 103912, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38810314

RESUMO

RESEARCH QUESTION: What are the metabolic characteristics of follicular fluid in patients with ovarian endometriosis undergoing IVF? DESIGN: This was an exploratory cohort study on endometriosis. In total, 19 infertile patients with ovarian endometriosis diagnosed by laparoscopy, and 23 controls matched in terms of age and body mass index (women with infertility due to male or tubal factors) were enrolled in this study. All patients underwent IVF treatment with a gonadotrophin-releasing hormone antagonist protocol, and follicular fluid was collected at oocyte retrieval. The metabolomics of follicular fluid samples was analysed using an ultra-high-performance liquid chromatography Orbitrap Exploris mass spectrometer (UHPLC-OE-MS). The best combination of biomarkers was selected by performing stepwise logistic regression analysis with backward elimination. RESULTS: Fifteen metabolites were identified as biomarkers associated with endometriosis. A final model containing 8-hydroxy-2-deoxyguanosine, biotin, n-acetyl-L-methionine and n-methylnicotinamide was constructed. Receiver operating characteristic analysis confirmed the value of these parameters in diagnosing endometriosis, with sensitivity of 94.7% and specificity of 95.7%. Enrichment analysis via the Kyoto Encyclopedia of Genes and Genome showed that 15 metabolites were enriched in eight metabolic pathways. CONCLUSION: Metabolomics based on UHPLC-OE-MS effectively characterized the metabolomics analysis of follicular fluid in patients with ovarian endometriosis. These findings may provide a new basis for better understanding of how diseases progress, and for the discovery of new biomarkers.

7.
BMC Pregnancy Childbirth ; 24(1): 38, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38183004

RESUMO

BACKGROUND: The risk factors associated with niche on the cesarean scar have been reported, however, the degree of these factors associated with large niche and the accumulation effects of these risk factors on the development of large niche are unclear. METHODS: Large niche was evaluated by transvaginal sonography during mid-follicular phase. Logistic regression model was used to assess 32 risk factors by univariate analysis. Then, a scoring model based on the screened risk factors was generated. The performance of this model was evaluated by area under curve (AUC). Finally, the scoring model was applied in 123 women to assess the external validation. RESULT(S): In the training cohort study, 163 women were diagnosed with large niche. The final scoring model involves eight risk factors with the rating scores including age at delivery (30-34 years: 1 point; ≥ 35 years: 4.5 points), retroflexed uterus (8.5 points), meconium-stained amniotic fluid (4.5 points), twice CSs (4.0 points), postpartum endometritis (4.5 points), premature rupture of membranes (2.5 points), intrahepatic cholestasis of pregnancy (mild to moderate: 3 points; severe: 6.5 points), and cervical dilatation (1-3 cm: 2.0 points; 4-10 cm: 4.5 points). The accumulation effect with a cut-off value of 8.0 in the scoring was associated with the large niche after CS. CONCLUSION(S): This is the first scoring model to objectively quantify the risk of a large niche after CS. Optimal risk factors control by avoiding high score factors and multiple factors accumulation may eliminate the risk of large niche development.


Assuntos
Cesárea , Colestase Intra-Hepática , Gravidez , Humanos , Feminino , Adulto , Cesárea/efeitos adversos , Estudos de Coortes , Área Sob a Curva , Fatores de Risco
8.
Cell Mol Biol Lett ; 29(1): 68, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38730334

RESUMO

BACKGROUND: Members of the nucleotide-binding oligomerization domain, leucine rich repeat and pyrin domain containing (NLRP) family regulate various physiological and pathological processes. However, none have been shown to regulate actin cap formation or spindle translocation during the asymmetric division of oocyte meiosis I. NLRP4E has been reported as a candidate protein in female fertility, but its function is unknown. METHODS: Immunofluorescence, reverse transcription polymerase chain reaction (RT-PCR), and western blotting were employed to examine the localization and expression levels of NLRP4E and related proteins in mouse oocytes. small interfering RNA (siRNA) and antibody transfection were used to knock down NLRP4E and other proteins. Immunoprecipitation (IP)-mass spectrometry was used to identify the potential proteins interacting with NLRP4E. Coimmunoprecipitation (Co-IP) was used to verify the protein interactions. Wild type (WT) or mutant NLRP4E messenger RNA (mRNA) was injected into oocytes for rescue experiments. In vitro phosphorylation was employed to examine the activation of steroid receptor coactivator (SRC) by NLRP4E. RESULTS: NLRP4E was more predominant within oocytes compared with other NLRP4 members. NLRP4E knockdown significantly inhibited actin cap formation and spindle translocation toward the cap region, resulting in the failure of polar body extrusion at the end of meiosis I. Mechanistically, GRIN1, and GANO1 activated NLRP4E by phosphorylation at Ser429 and Thr430; p-NLRP4E is translocated and is accumulated in the actin cap region during spindle translocation. Next, we found that p-NLRP4E directly phosphorylated SRC at Tyr418, while p-SRC negatively regulated p-CDC42-S71, an inactive form of CDC42 that promotes actin cap formation and spindle translocation in the GTP-bound form. CONCLUSIONS: NLRP4E activated by GRIN1 and GANO1 regulates actin cap formation and spindle translocation toward the cap region through upregulation of p-SRC-Tyr418 and downregulation of p-CDC42-S71 during meiosis I.


Assuntos
Actinas , Meiose , Oócitos , Proteína cdc42 de Ligação ao GTP , Animais , Oócitos/metabolismo , Camundongos , Feminino , Actinas/metabolismo , Actinas/genética , Proteína cdc42 de Ligação ao GTP/metabolismo , Proteína cdc42 de Ligação ao GTP/genética , Fosforilação , Fuso Acromático/metabolismo
9.
Proc Natl Acad Sci U S A ; 118(41)2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34607954

RESUMO

BRCA1 germline mutations are associated with an increased risk of breast and ovarian cancer. Recent findings of others suggest that BRCA1 mutation carriers also bear an increased risk of esophageal and gastric cancer. Here, we employ a Brca1/Trp53 mouse model to show that unresolved replication stress (RS) in BRCA1 heterozygous cells drives esophageal tumorigenesis in a model of the human equivalent. This model employs 4-nitroquinoline-1-oxide (4NQO) as an RS-inducing agent. Upon drinking 4NQO-containing water, Brca1 heterozygous mice formed squamous cell carcinomas of the distal esophagus and forestomach at a much higher frequency and speed (∼90 to 120 d) than did wild-type (WT) mice, which remained largely tumor free. Their esophageal tissue, but not that of WT control mice, revealed evidence of overt RS as reflected by intracellular CHK1 phosphorylation and 53BP1 staining. These Brca1 mutant tumors also revealed higher genome mutation rates than those of control animals; the mutational signature SBS4, which is associated with tobacco-induced tumorigenesis; and a loss of Brca1 heterozygosity (LOH). This uniquely accelerated Brca1 tumor model is also relevant to human esophageal squamous cell carcinoma, an often lethal tumor.


Assuntos
Proteína BRCA1/genética , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/genética , Perda de Heterozigosidade/genética , Proteína Supressora de Tumor p53/genética , 4-Nitroquinolina-1-Óxido/toxicidade , Animais , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Quinase 1 do Ponto de Checagem/metabolismo , Modelos Animais de Doenças , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/induzido quimicamente , Carcinoma de Células Escamosas do Esôfago/patologia , Feminino , Mutação em Linhagem Germinativa/genética , Heterozigoto , Humanos , Perda de Heterozigosidade/efeitos dos fármacos , Masculino , Camundongos , Camundongos Knockout , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/metabolismo
10.
Molecules ; 29(7)2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38611949

RESUMO

Olibanum is a resinous traditional Chinese medicine that is directly used as a powder. It is widely used in China and is often combined with other traditional Chinese medicine powders to promote blood circulation and relieve pain, as well as to treat rheumatism, rheumatoid arthritis, and osteoarthritis. Powdered traditional Chinese medicine is often easily contaminated by microorganisms and 60Co irradiation is one of the good sterilization methods. Volatile organic compounds (VOCs) are the main active ingredient of olibanum. The aim of this study was to validate the optimum doses of 60Co irradiation and its effect on VOCs. 60Co irradiation was applied in different doses of 0 kGy, 1.5 kGy, 3.0 kGy, and 6.0 kGy. Changes in VOCs were detected using gas chromatography ion mobility spectrometry. A total of 81 VOCs were identified. The odor fingerprint results showed that, with an increase in irradiation dose, most of the VOCs of olibanum changed. Through principal component analysis, cluster analysis, and partial least squares discriminant analysis, it was demonstrated that, at 1.5 kGy, the impact of radiation on the VOCs of olibanum was minimal, indicating this is a relatively good irradiation dose. This study provides a theoretical basis for the irradiation processing and quality control of resinous medicinal materials such as olibanum and it also provides a good reference for irradiation technology development and its application to functional foods, thus making it both significant from a research perspective and useful from an application perspective.


Assuntos
Radioisótopos de Cobalto , Franquincenso , Compostos Orgânicos Voláteis , Espectrometria de Mobilidade Iônica , Cromatografia Gasosa-Espectrometria de Massas , Resinas Vegetais
11.
J Neurosci ; 42(29): 5755-5770, 2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35705488

RESUMO

Extinguishing the previously acquired fear is critical for the adaptation of an organism to the ever-changing environment, a process requiring the engagement of GABAA receptors (GABAARs). GABAARs consist of tens of structurally, pharmacologically, and functionally heterogeneous subtypes. However, the specific roles of these subtypes in fear extinction remain largely unexplored. Here, we observed that in the medial prefrontal cortex (mPFC), a core region for mood regulation, the extrasynaptically situated, δ-subunit-containing GABAARs [GABAA(δ)Rs], had a permissive role in tuning fear extinction in male mice, an effect sharply contrasting to the established but suppressive role by the whole GABAAR family. First, the fear extinction in individual mice was positively correlated with the level of GABAA(δ)R expression and function in their mPFC. Second, knockdown of GABAA(δ)R in mPFC, specifically in its infralimbic (IL) subregion, sufficed to impair the fear extinction in mice. Third, GABAA(δ)R-deficient mice also showed fear extinction deficits, and re-expressing GABAA(δ)Rs in the IL of these mice rescued the impaired extinction. Further mechanistic studies demonstrated that the permissive effect of GABAA(δ)R was associated with its role in enabling the extinction-evoked plastic regulation of neuronal excitability in IL projection neurons. By contrast, GABAA(δ)R had little influence on the extinction-evoked plasticity of glutamatergic transmission in these cells. Altogether, our findings revealed an unconventional and permissive role of extrasynaptic GABAA receptors in fear extinction through a route relying on nonsynaptic plasticity.SIGNIFICANCE STATEMENT The medial prefrontal cortex (mPFC) is one of the kernel brain regions engaged in fear extinction. Previous studies have repetitively shown that the GABAA receptor (GABAAR) family in this region act to suppress fear extinction. However, the roles of specific GABAAR subtypes in mPFC are largely unknown. We observed that the GABAAR-containing δ-subunit [GABAA(δ)R], a subtype of GABAARs exclusively situated in the extrasynaptic membrane and mediating the tonic neuronal inhibition, works oppositely to the whole GABAAR family and promotes (but does not suppress) fear extinction. More interestingly, in striking contrast to the synaptic GABAARs that suppress fear extinction by breaking the extinction-evoked plasticity of glutamatergic transmission, the GABAA(δ)R promotes fear extinction through enabling the plastic regulation of neuronal excitability in the infralimbic subregion of mPFC. Our findings thus reveal an unconventional role of GABAA(δ)R in promoting fear extinction through a route relying on nonsynaptic plasticity.


Assuntos
Extinção Psicológica , Medo , Animais , Medo/fisiologia , Masculino , Camundongos , Neurônios/metabolismo , Plásticos/metabolismo , Plásticos/farmacologia , Córtex Pré-Frontal/fisiologia , Receptores de GABA-A/metabolismo , Ácido gama-Aminobutírico/farmacologia
12.
Glia ; 71(7): 1715-1728, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36971019

RESUMO

Our previous studies indicated that RhoA knockdown or inhibition could alleviate the proliferation, migration, and differentiation of Schwann cells. However, the role of RhoA in Schwann cells during nerve injury and repair is still unknown. Herein, we developed two lines of Schwann cells conditional RhoA knockout (cKO) mice by breeding RhoAflox / flox mice with PlpCre -ERT2 or DhhCre mice. Our results indicate that RhoA cKO in Schwann cells accelerates axonal regrowth and remyelination after sciatic nerve injury, which enhances the recovery of nerve conduction and hindlimb gait, and alleviates the amyotrophy in gastrocnemius muscle. Mechanistic studies in both in vivo and in vitro models revealed that RhoA cKO could facilitate Schwann cell dedifferentiation via JNK pathway. Schwann cell dedifferentiation subsequently promotes Wallerian degeneration by enhancing phagocytosis and myelinophagy, as well as stimulating the production of neurotrophins (NT-3, NGF, BDNF, and GDNF). These findings shed light on the role of RhoA in Schwann cells during nerve injury and repair, indicating that cell type-specific RhoA targeting could serve as a promising molecular therapeutic strategy for peripheral nerve injury.


Assuntos
Traumatismos dos Nervos Periféricos , Neuropatia Ciática , Camundongos , Animais , Desdiferenciação Celular , Nervo Isquiático/metabolismo , Células de Schwann/metabolismo , Neuropatia Ciática/metabolismo , Regeneração Nervosa/fisiologia , Traumatismos dos Nervos Periféricos/metabolismo
13.
Cell Mol Neurobiol ; 43(7): 3161-3178, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37338781

RESUMO

Glaucoma is a group of diseases characterized by the degeneration of retinal ganglion cells (RGCs) and progressive, irreversible vision loss. High intraocular pressure (IOP) heightens the likelihood of glaucoma and correlates with RGC loss. While the current glaucoma therapy prioritizes lower the IOP; however, RGC, and visual loss may persist even when the IOP is well-controlled. As such, discovering and creating IOP-independent neuroprotective strategies for safeguard RGCs is crucial for glaucoma management. Investigating and clarifying the mechanism behind RGC death to counteract its effects is a promising direction for glaucoma control. Empirical studies of glaucoma reveal the role of multiple regulated cell death (RCD) pathways in RGC death. This review delineates the RCD of RGCs following IOP elevation and optic nerve damage and discusses the substantial benefits of mitigating RCD in RGCs in preserving visual function.


Assuntos
Glaucoma , Morte Celular Regulada , Animais , Células Ganglionares da Retina/metabolismo , Pressão Intraocular , Glaucoma/terapia , Glaucoma/metabolismo , Neuroproteção , Modelos Animais de Doenças
14.
Biometrics ; 79(3): 2157-2170, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-35894546

RESUMO

The existing methods for subgroup analysis can be roughly divided into two categories: finite mixture models (FMM) and regularization methods with an ℓ1 -type penalty. In this paper, by introducing the group centers and ℓ2 -type penalty in the loss function, we propose a novel center-augmented regularization (CAR) method; this method can be regarded as a unification of the regularization method and FMM and hence exhibits higher efficiency and robustness and simpler computations than the existing methods. In particular, its computational complexity is reduced from the O ( n 2 ) $O(n^2)$ of the conventional pairwise-penalty method to only O ( n K ) $O(nK)$ , where n is the sample size and K is the number of subgroups. The asymptotic normality of CAR is established, and the convergence of the algorithm is proven. CAR is applied to a dataset from a multicenter clinical trial, Buprenorphine in the Treatment of Opiate Dependence; a larger R2 is produced and three additional significant variables are identified compared to those of the existing methods.


Assuntos
Algoritmos , Aprendizagem
15.
Bioorg Chem ; 141: 106869, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37797454

RESUMO

The opioids have been used for more than a thousand years and are not only the most widely prescribed drugs for moderate to severe pain and acute pain, but also the preferred drugs. However, their non-analgesic effects, especially respiratory depression and potential addiction, are important factors that plague the safety of clinical use and are an urgent problem for pharmacological researchers to address. Current research on analgesic drugs has evolved into different directions: de-opioidization; application of pharmacogenomics to individualize the use of opioids; development of new opioids with less adverse effects. The development of new opioid drugs remains a hot research topic, and with the in-depth study of opioid receptors and intracellular signal transduction mechanisms, new research ideas have been provided for the development of new opioid analgesics with less side effects and stronger analgesic effects. The development of novel opioid drugs in turn includes selective opioid receptor ligands, biased opioid receptor ligands, and multi-target opioid receptor ligands and positive allosteric modulators (PAMs) or antagonists and the single compound as multi-targeted agnoists/antagonists for different receptors. PAMs strategies are also getting newer and are the current research hotspots, including the BMS series of compounds and others, which are extensive and beyond the scope of this review. This review mainly focuses on the selective/biased/multi-targeted MOR/DOR/KOR (mu opioid receptor/delta opioid receptor/kappa opioid receptor) small molecule ligands and involves some cryo-electron microscopy (cryoEM) and structure-based approaches as well as the single compound as multi-targeted agnoists/antagonists for different receptors from 2019 to 2022, including discovery history, activities in vitro and vivo, and clinical studies, in an attempt to provide ideas for the development of novel opioid analgesics with fewer side effects.


Assuntos
Analgésicos Opioides , Receptores Opioides kappa , Analgésicos Opioides/farmacologia , Analgésicos Opioides/uso terapêutico , Receptores Opioides mu , Microscopia Crioeletrônica , Analgésicos , Ligantes
16.
Cell Mol Life Sci ; 79(1): 63, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35006382

RESUMO

Conventional angiogenic factors, such as vascular endothelial growth factor (VEGF), regulate both pathological and physiological angiogenesis indiscriminately, and their inhibitors may elicit adverse side effects. Secretogranin III (Scg3) was recently reported to be a diabetes-restricted VEGF-independent angiogenic factor, but the disease selectivity of Scg3 in retinopathy of prematurity (ROP), a retinal disease in preterm infants with concurrent pathological and physiological angiogenesis, was not defined. Here, using oxygen-induced retinopathy (OIR) mice, a surrogate model of ROP, we quantified an exclusive binding of Scg3 to diseased versus healthy developing neovessels that contrasted sharply with the ubiquitous binding of VEGF. Functional immunohistochemistry visualized Scg3 binding exclusively to disease-related disorganized retinal neovessels and neovascular tufts, whereas VEGF bound to both disorganized and well-organized neovessels. Homozygous deletion of the Scg3 gene showed undetectable effects on physiological retinal neovascularization but markedly reduced the severity of OIR-induced pathological angiogenesis. Furthermore, anti-Scg3 humanized antibody Fab (hFab) inhibited pathological angiogenesis with similar efficacy to anti-VEGF aflibercept. Aflibercept dose-dependently blocked physiological angiogenesis in neonatal retinas, whereas anti-Scg3 hFab was without adverse effects at any dose and supported a therapeutic window at least 10X wider than that of aflibercept. Therefore, Scg3 stringently regulates pathological but not physiological angiogenesis, and anti-Scg3 hFab satisfies essential criteria for development as a safe and effective disease-targeted anti-angiogenic therapy for ROP.


Assuntos
Inibidores da Angiogênese/farmacologia , Cromograninas/imunologia , Cromograninas/metabolismo , Neovascularização Patológica/genética , Neovascularização Retiniana/patologia , Retinopatia da Prematuridade/patologia , Animais , Capilares/metabolismo , Cromograninas/antagonistas & inibidores , Cromograninas/genética , Modelos Animais de Doenças , Fragmentos Fab das Imunoglobulinas/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oxigênio/efeitos adversos , Receptores de Fatores de Crescimento do Endotélio Vascular , Proteínas Recombinantes de Fusão/farmacologia , Neovascularização Retiniana/genética , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores
17.
Graefes Arch Clin Exp Ophthalmol ; 261(12): 3437-3447, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37566303

RESUMO

PURPOSE: To assess the relationship between the distribution of intra-retinal hyper-reflective foci (IHRF) on optical coherence tomography (OCT) and progression of intermediate age-related macular degeneration (iAMD) over 2 years. METHODS: Cirrus OCT volumes of the macula of subjects enrolled in the Amish Eye Study with 2 years of follow-up were evaluated for the presence of iAMD and IHRF at baseline. The IHRF were counted in a series of 5 sequential en face slabs from outer to inner retina. The number of IHRF in each slab at baseline and the change in IHRF from baseline to year 2 were correlated with progression to late AMD at 2 years. RESULTS: Among 120 eyes from 71 patients with iAMD, 52 eyes (43.3%) of 42 patients had evidence of both iAMD and IHRF at baseline. Twenty-three eyes (19.0%) showed progression to late AMD after 2 years. The total IHRF count increased from 243 at baseline to 604 at 2 years, with a significant increase in the IHRF number in each slab, except for the innermost slab 5 which had no IHRF at baseline or follow-up. The IHRF count increased from 121 to 340 in eyes that showed progression to late AMD. The presence of IHRF in the outermost retinal slabs 1 and 2 was independently associated with a significant risk of progression to late AMD. A greater increase in IHRF count over 2 years in these same slabs 1 and 2 was also associated with a higher risk of conversion to late AMD. CONCLUSIONS: The risk of progression to late AMD appears to be significantly associated with the distribution and extent of IHRF in the outermost retinal layers. This observation may point to significant pathophysiologic differences of IHRF in inner versus outer layers of the retina.


Assuntos
Macula Lutea , Degeneração Macular , Humanos , Pré-Escolar , Progressão da Doença , Retina , Degeneração Macular/complicações , Tomografia de Coerência Óptica/métodos , Angiofluoresceinografia
18.
Graefes Arch Clin Exp Ophthalmol ; 261(11): 3165-3176, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37392262

RESUMO

PURPOSE: To assess the relationship between qualitative diabetic retinopathy (DR) scales with the precise numbers and surface area of DR lesions within the Early Treatment Diabetic Retinopathy Study (ETDRS) standard seven field (S7F) region on ultrawide-field (UWF) color fundus images. METHODS: In this study, we collected UWF images from adult patients with diabetes. Poor-quality images and eyes with any pathology precluding assessment of DR severity were excluded. The DR lesions were manually segmented. DR severity was graded according to the International Clinical Diabetic Retinopathy (ICDR) and AA protocol by two masked graders within the ETDRS S7F. These lesions' numbers and surface area were computed and correlated against the DR scores using the Kruskal-Wallis H test. Cohen's Kappa was performed to determine the agreement between two graders. RESULTS: One thousand five hundred and twenty eyes of 869 patients (294 females, 756 right eyes) with a mean age of 58.7 years were included. 47.4% were graded as no DR, 2.2% as mild non-proliferative DR (NPDR), 24.0% as moderate NPDR, 6.3% as severe NPDR, and 20.1% as proliferative DR (PDR). The area and number of DR lesions generally increased as the ICDR level increased up to severe NPDR, but decreased from severe NPDR to PDR. There was perfect intergrader agreement on the DR severity. CONCLUSION: A quantitative approach reveals that DR lesions' number and area generally correlate with ICDR-based categorical DR severity levels with an increasing trend in the number and area of DR lesions from mild to severe NPDR and a decrease from severe NPDR to PDR.

19.
BMC Nephrol ; 24(1): 184, 2023 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-37349734

RESUMO

BACKGROUND: Relationships between adulthood modifiable risk factors and chronic kidney disease (CKD) are well-established, but associations with childhood risk factors are unclear. This study systematically assesses the published evidence about childhood modifiable risk factors and adulthood CKD. METHODS: We searched MEDLINE, EMBASE, and Web of Science to 6th May 2022. Articles were included if (1) they were population-based longitudinal studies, (2) exposures were potentially modifiable, for example through pharmacological or lifestyle modifications, including clinical conditions/measures (diabetes, blood pressure, adiposity, and dyslipidaemia); health behaviours (smoking, alcohol consumption, physical activity, fitness, and poor nutrition); and socio-economic factors (socio-economic position), and occurred during childhood (ages 2-19 years), and (3) outcome was CKD or surrogate markers of CKD in adulthood (ages 20 years or older). Three reviewers independently extracted the data. RESULTS: 15,232 articles were identified after deduplication; 17 articles met the inclusion criteria, reporting childhood blood pressure (n = 8), adiposity (n = 4), type 2 diabetes (n = 1), socio-economic position (n = 1), famine (n = 1), cardiorespiratory fitness (n = 1), and a healthy lifestyle score (n = 1). The results suggested positive associations of childhood adiposity, type 2 diabetes, and low socio-economic position and cardiorespiratory fitness in females with CKD in adulthood. Findings were inconsistent on associations between childhood BP and CKD in adulthood. Childhood healthy lifestyle score and exposure to famine were not associated with risk of CKD in adulthood. CONCLUSIONS: The limited evidence suggests childhood factors may contribute to the CKD risk in adulthood, particularly adiposity, type 2 diabetes, and low socio-economic position and cardiorespiratory fitness in females. Further high-quality community-based studies are needed with long-term follow-up and investigation of a broader range of modifiable risk factors.


Assuntos
Diabetes Mellitus Tipo 2 , Insuficiência Renal Crônica , Feminino , Humanos , Diabetes Mellitus Tipo 2/complicações , Fatores de Risco , Obesidade/complicações , Pressão Sanguínea , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/complicações
20.
J Cell Physiol ; 237(5): 2357-2373, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35288937

RESUMO

Polypyrimidine tract-binding protein (PTB), as a member of the heterogeneous nuclear ribonucleoprotein family, functions by rapidly shuttling between the nucleus and the cytoplasm. PTB is involved in the alternative splicing of pre-messenger RNA (mRNA) and almost all steps of mRNA metabolism. PTB regulation is organ-specific; brain- or muscle-specific microRNAs and long noncoding RNAs partially contribute to regulating PTB, thereby modulating many physiological and pathological processes, such as embryonic development, cell development, spermatogenesis, and neuron growth and differentiation. Previous studies have shown that PTB knockout can inhibit tumorigenesis and development. The knockout of PTB in glial cells can be reprogrammed into functional neurons, which shows great promise in the field of nerve regeneration but is controversial.


Assuntos
Ribonucleoproteínas Nucleares Heterogêneas , Proteína de Ligação a Regiões Ricas em Polipirimidinas , Processamento Alternativo/genética , Ribonucleoproteínas Nucleares Heterogêneas/genética , Neurônios/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , RNA Mensageiro/genética
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