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1.
N Engl J Med ; 390(3): 230-241, 2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-38231624

RESUMEN

BACKGROUND: Simnotrelvir is an oral 3-chymotrypsin-like protease inhibitor that has been found to have in vitro activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and potential efficacy in a phase 1B trial. METHODS: In this phase 2-3, double-blind, randomized, placebo-controlled trial, we assigned patients who had mild-to-moderate coronavirus disease 2019 (Covid-19) and onset of symptoms within the past 3 days in a 1:1 ratio to receive 750 mg of simnotrelvir plus 100 mg of ritonavir or placebo twice daily for 5 days. The primary efficacy end point was the time to sustained resolution of symptoms, defined as the absence of 11 Covid-19-related symptoms for 2 consecutive days. Safety and changes in viral load were also assessed. RESULTS: A total of 1208 patients were enrolled at 35 sites in China; 603 were assigned to receive simnotrelvir and 605 to receive placebo. Among patients in the modified intention-to-treat population who received the first dose of trial drug or placebo within 72 hours after symptom onset, the time to sustained resolution of Covid-19 symptoms was significantly shorter in the simnotrelvir group than in the placebo group (180.1 hours [95% confidence interval {CI}, 162.1 to 201.6] vs. 216.0 hours [95% CI, 203.4 to 228.1]; median difference, -35.8 hours [95% CI, -60.1 to -12.4]; P = 0.006 by Peto-Prentice test). On day 5, the decrease in viral load from baseline was greater in the simnotrelvir group than in the placebo group (mean difference [±SE], -1.51±0.14 log10 copies per milliliter; 95% CI, -1.79 to -1.24). The incidence of adverse events during treatment was higher in the simnotrelvir group than in the placebo group (29.0% vs. 21.6%). Most adverse events were mild or moderate. CONCLUSIONS: Early administration of simnotrelvir plus ritonavir shortened the time to the resolution of symptoms among adult patients with Covid-19, without evident safety concerns. (Funded by Jiangsu Simcere Pharmaceutical; ClinicalTrials.gov number, NCT05506176.).


Asunto(s)
COVID-19 , Inhibidores de Proteasa de Coronavirus , Adulto , Humanos , Administración Oral , Antivirales/administración & dosificación , Antivirales/efectos adversos , Antivirales/farmacología , Antivirales/uso terapéutico , China , Proteínas M de Coronavirus/antagonistas & inhibidores , Proteínas M de Coronavirus/metabolismo , Inhibidores de Proteasa de Coronavirus/administración & dosificación , Inhibidores de Proteasa de Coronavirus/efectos adversos , Inhibidores de Proteasa de Coronavirus/farmacología , Inhibidores de Proteasa de Coronavirus/uso terapéutico , COVID-19/metabolismo , COVID-19/terapia , Tratamiento Farmacológico de COVID-19/métodos , Método Doble Ciego , Ritonavir/administración & dosificación , Ritonavir/efectos adversos , Ritonavir/farmacología , Ritonavir/uso terapéutico , SARS-CoV-2/efectos de los fármacos , Factores de Tiempo , Combinación de Medicamentos
2.
Small ; 20(5): e2305762, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37759422

RESUMEN

In the search for sustainable cathode materials for aqueous zinc ion batteries (AZIBs), vanadium (V)-based materials have garnered interest, primarily due to their abundance and multiple oxidation states. Among the contenders, Li3 VO4 (LiVO) stands out for its affordability, high specific capacity, and elevated ionic conductivity. However, its limited electrical conductivity results in significant resistance polarization, limiting its rate capability, especially under high currents. Through density functional theory (DFT) calculations, this study evaluates the electrochemical implications of carbon (C) incorporation within the LiVO matrix. The findings indicate that C integration significantly ameliorates the conductivity of LiVO. Moreover, C serves as a barrier, mitigating direct interactions between Zn2+ and LiVO, which in turn expedites Zn2+ diffusion. When considering various C materials for this role, glucose is emerged as the optimal candidate. The LiVO/C-glucose composite (LiVO/C-G) is observed to undergo dual phase transitions during charge-discharge cycles, resulting in an amorphous vanadium-oxygen (VO) derivative, paving the way for subsequent electrochemical reactions. Collectively, the insights pave a promising avenue for refining AZIB cathode design and performance.

3.
Small ; 19(39): e2301870, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37236170

RESUMEN

Aqueous zinc ion batteries (AZIBs) have attracted attention as a promising candidate for secondary battery energy storage due to their safety and environmental benefits. However, the vanadium-based cathode material NH4 V4 O10 has the problem of structural instability. In this paper, it is found by density functional theory calculation that excessive NH4 + located in the interlayer will repel the Zn2+ during the process of Zn2+ insertion. This results in the distortion of the layered structure, further affects the diffusion of Zn2+ and reduces the reaction kinetics. Therefore, part of the NH4 + is removed by heat treatment. In addition, the introduction of Al3+ into the material by hydrothermal method is able to further enhance its zinc storage properties. This dual-engineering strategy shows excellent electrochemical performance (578.2 mAh g-1 at 0.2 A g-1 ). This study provides valuable insights for the development of high performance AZIBs cathode materials.

4.
Small ; 19(50): e2304668, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37626454

RESUMEN

The inherent slow diffusion dynamics of aqueous zinc-ion batteries (AZIBs) act as a significant hindrance to their universal utilization as energy storage systems, largely attributed to the scarcity of superior cathode materials. In this study, a novel method that amalgamates oxygen defect engineering and polymer intercalation, guided by theoretical computations, to confront this challenge, is introduced. This approach begins with density functional theory calculations, demonstrating that the shielding effect rendered by polypyrrole (PPy) between NH4 V3 O8 (NVO) layers, along with the cooperative influence of oxygen defects (Od ), optimizes the kinetic transport of Zn2+ . Leveraging these theoretical outcomes, a two-step hydrothermal synthesis procedure is devised to fabricate PPy-intercalated NVO embedded with Od (NVO-Od @PPy). The empirical findings corroborate the theoretical predictions, showcasing that the NVO-Od @PPy//Zn system manifests exceptional cycling stability. Specifically, the NVO-Od @PPy electrode delivers an optimal reversible capacity, yielding 421 mAh g-1 at a current density of 0.1 A g-1 . Remarkably, even at an elevated current density of 10 A g-1 , it sustains a capacity of 175.7 mAh g-1 , while maintaining a capacity retention of 99% over 1000 cycles. This research provides pivotal insights for the engineering of high-performing cathode materials for AZIBs, paving the way for their future advancements.

5.
Small ; 18(47): e2204180, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36228084

RESUMEN

Aqueous zinc ion batteries are a promising alternative secondary battery technology due to their excellent safety and environmental friendliness. Vanadium-based compounds as a highly promising class of cathode materials still suffer from structural collapse and slow kinetics. Studies have shown that metal ion pre-introduction is an effective method to solve these problems and enhance battery performance. Here, the introduction of Al3+ , Cr3+ , Cu2+ and Fe3+ is found to effectively reduce the migration energy barrier of Zn2+ with the density functional theory calculations, while Al3+ exhibits the best induction effects. Subsequently, Al0.34 V5 O12 ·2.4H2 O (AlVOH) nanoribbons are synthesized by hydrothermal introduction of Al3+ , demonstratin excellent electrochemical properties (407.8 mAh g-1 at 0.2 A g-1 and 176.3 mAh g-1 after 2000 cycles at 20 A g-1 ). By further compounding with redox graphene (rGO), AlVOH/rGO exhibits high capacitance and specific capacity (460.4 mAh g-1 at 0.2 A g-1 and 180.6 mAh g-1 after 2000 cycles at 20 A g-1 ). In addition, it is found that the introduction of metal ions adjusts the structural water content of the material. Especially, the introduction of Al3+ can increase the interlayer structural water content and make the electrochemical properties of the material more stable.

6.
Int J Mol Sci ; 20(19)2019 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-31569411

RESUMEN

In central lymphoid tissues, mature lymphocytes are generated and pathogenic autoreactive lymphocytes are deleted. However, it is currently known that a significant number of potentially pathogenic autoreactive lymphocytes escape the deletion and populate peripheral lymphoid tissues. Therefore, peripheral mechanisms are present to prevent these potentially pathogenic autoreactive lymphocytes from harming one's own tissues. One such mechanism is dictated by regulatory T (Treg) cells. So far, the most extensively studied Treg cells are CD4+Foxp3+ Treg cells. However, recent clinical trials for the treatment of immune-mediated diseases using CD4+ Foxp3+ Treg cells met with limited success. Accordingly, it is necessary to explore the potential importance of other Treg cells such as CD8+ Treg cells. In this regard, one extensively studied CD8+ Treg cell subset is Qa-1(HLA-E in human)-restricted CD8+ Treg cells, in which Qa-1(HLA-E) molecules belong to a group of non-classical major histocompatibility complex Ib molecules. This review will first summarize the evidence for the presence of Qa-1-restricted CD8+ Treg cells and their regulatory mechanisms. Major discussions will then focus on the potential clinical translation of Qa-1-restricted CD8+ Treg cells. At the end, we will briefly discuss the current status of human studies on HLA-E-restricted CD8+ Treg cells as well as potential future directions.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Antígenos de Histocompatibilidad Clase I/inmunología , Linfocitos T Reguladores/inmunología , Investigación Biomédica Traslacional , Animales , Linfocitos T CD8-positivos/metabolismo , Epítopos/inmunología , Humanos , Enfermedades del Sistema Inmune/etiología , Enfermedades del Sistema Inmune/metabolismo , Enfermedades del Sistema Inmune/terapia , Inmunomodulación , Péptidos/inmunología , Linfocitos T Reguladores/metabolismo , Vacunación
7.
Cells ; 13(17)2024 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-39273035

RESUMEN

Inflammatory bowel disease (IBD) is a chronic inflammatory disorder in the intestines without a cure. Current therapies suppress inflammation to prevent further intestinal damage. However, healing already damaged intestinal epithelia is still an unmet medical need. Under physiological conditions, Lgr5+ intestinal stem cells (ISCs) in the intestinal crypts replenish the epithelia every 3-5 days. Therefore, understanding the regulation of Lgr5+ ISCs is essential. Previous data suggest vitamin D signaling is essential to maintain normal Lgr5+ ISC function in vivo. Our recent data indicate that to execute its functions in the intestines optimally, 1,25(OH)2D requires high concentrations that, if present systemically, can cause hypercalcemia (i.e., blood calcium levels significantly higher than physiological levels), leading to severe consequences. Using 5-bromo-2'-deoxyuridine (BrdU) to label the actively proliferating ISCs, our previous data suggested that de novo synthesized locally high 1,25(OH)2D concentrations effectively enhanced the migration and differentiation of ISCs without causing hypercalcemia. However, although sparse in the crypts, other proliferating cells other than Lgr5+ ISCs could also be labeled with BrdU. This current study used high-purity Lgr5+ ISC lines and a mouse strain, in which Lgr5+ ISCs and their progeny could be specifically tracked, to investigate the effects of de novo synthesized locally high 1,25(OH)2D concentrations on Lgr5+ ISC function. Our data showed that 1,25(OH)2D at concentrations significantly higher than physiological levels augmented Lgr5+ ISC differentiation in vitro. In vivo, de novo synthesized locally high 1,25(OH)2D concentrations significantly elevated local 1α-hydroxylase expression, robustly suppressed experimental colitis, and promoted Lgr5+ ISC differentiation. For the first time, this study definitively demonstrated 1,25(OH)2D's role in Lgr5+ ISCs, underpinning 1,25(OH)2D's promise in IBD therapy.


Asunto(s)
Receptores Acoplados a Proteínas G , Células Madre , Vitamina D , Animales , Receptores Acoplados a Proteínas G/metabolismo , Células Madre/metabolismo , Células Madre/efectos de los fármacos , Células Madre/citología , Vitamina D/farmacología , Vitamina D/análogos & derivados , Vitamina D/metabolismo , Ratones , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efectos de los fármacos , Regeneración/efectos de los fármacos , Ratones Endogámicos C57BL , Colitis/metabolismo , Colitis/inducido químicamente , Colitis/patología , Intestinos/efectos de los fármacos
8.
Lancet Infect Dis ; 24(2): 129-139, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38006892

RESUMEN

BACKGROUND: Spread of SARS-CoV-2 led to a global pandemic, and there remains unmet medical needs in the treatment of Omicron infections. VV116, an oral antiviral agent that has potent activity against SARS-CoV-2, was compared with a placebo in this phase 3 study to investigate its efficacy and safety in patients with mild-to-moderate COVID-19. METHODS: This multicentre, double-blind, phase 3, randomised controlled study enrolled adults in hospitals for infectious diseases and tertiary general hospitals in China. Eligible patients were randomly assigned in a 1:1 ratio using permuted block randomisation to receive oral VV116 (0·6 g every 12 h on day 1 and 0·3 g every 12 h on days 2-5) or oral placebo (on the same schedule as VV116) for 5 days. Randomisation stratification factors included SARS-CoV-2 vaccination status and the presence of high-risk factors for progression to severe COVID-19. Inclusion criteria were a positive SARS-CoV-2 test, an initial onset of COVID-19 symptoms 3 days or less before the first study dose, and a score of 2 or more for any target COVID-19-related symptoms in the 24 h before the first dose. Patients who had severe or critical COVID-19 or who had taken any antiviral drugs were excluded from the study. The primary endpoint was the time to clinical symptom resolution for 2 consecutive days. Efficacy analyses were performed on a modified intention-to-treat population, comprising all patients who received at least one dose of VV116 or placebo, tested positive for SARS-CoV-2 nucleic acid, and did not test positive for influenza virus before the first dose. Safety analyses were done on all participants who received at least one dose of VV116 or placebo. This study was registered with ClinicalTrials.gov, NCT05582629, and has been completed. FINDINGS: A total of 1369 patients were randomly assigned to treatment groups and 1347 received either VV116 (n=674) or placebo (n=673). At the interim analysis, VV116 was superior to placebo in reducing the time to sustained clinical symptom resolution among 1229 patients (hazard ratio [HR] 1·21, 95% CI 1·04-1·40; p=0·0023). At the final analysis, a substantial reduction in time to sustained clinical symptom resolution was observed for VV116 compared with placebo among 1296 patients (HR 1·17, 95% CI 1·04-1·33; p=0·0009), consistent with the interim analysis. The incidence of adverse events was similar between groups (242 [35·9%] of 674 patients vs 283 [42·1%] of 673 patients). INTERPRETATION: Among patients with mild-to-moderate COVID-19, VV116 significantly reduced the time to sustained clinical symptom resolution compared with placebo, with no observed safety concerns. FUNDING: Shanghai Vinnerna Biosciences, Shanghai Science and Technology Commission, and the National Key Research and Development Program of China. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Asunto(s)
Adenosina , COVID-19 , Adulto , Humanos , SARS-CoV-2 , Vacunas contra la COVID-19 , China/epidemiología , Método Doble Ciego , Adenosina/análogos & derivados
9.
J Vis Exp ; (155)2020 01 22.
Artículo en Inglés | MEDLINE | ID: mdl-32065153

RESUMEN

Inflammatory bowel disease (IBD) is an inflammatory chronic disease in the gastrointestinal tract (GUT). In the United States, there are approximately 1.4 million IBD patients. It is generally accepted that a dysregulated immune response to gut bacteria initiates the disease and disrupts the mucosal epithelial barrier. We recently show that gut-homing regulatory T (Treg) cells are a promising therapy for IBD. Accordingly, this article presents a protocol for in vivo augmentation of gut-homing Treg cell induction. In this protocol, dendritic cells are engineered to produce locally high concentrations of two molecules de novo, active vitamin D (1,25-dihydroxyvitamin D or 1,25[OH]2D) and active vitamin A (retinoic acid or RA). We chose 1,25(OH)2D and RA based on previous findings showing that 1,25(OH)2D can induce the expression of regulatory molecules (e.g., forkhead box P3 and interleukin-10) and that RA can stimulate the expression of gut-homing receptors in T cells. To generate such engineered dendritic cells, we use a lentiviral vector to transduce dendritic cells to overexpress two genes. One gene is the cytochrome P450 family 27 subfamily B member 1 that encodes 25-hydroxyvitamin D 1α-hydroxylase, which physiologically catalyzes the synthesis of 1,25(OH)2D. The other gene is the aldehyde dehydrogenase 1 family member A2 that encodes retinaldehyde dehydrogenase 2, which physiologically catalyzes the synthesis of RA. This protocol can be used for future investigation of gut-homing Treg cells in vivo.


Asunto(s)
Enfermedades Inflamatorias del Intestino/inmunología , Linfocitos T Reguladores/inmunología , Humanos
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