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1.
PLoS Pathog ; 20(7): e1012362, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38976759

RESUMO

Filamentous cell growth is a vital property of fungal pathogens. The mechanisms of filamentation in the emerging multidrug-resistant fungal pathogen Candida auris are poorly understood. Here, we show that exposure of C. auris to glycerol triggers a rod-like filamentation-competent (RL-FC) phenotype, which forms elongated filamentous cells after a prolonged culture period. Whole-genome sequencing analysis reveals that all RL-FC isolates harbor a mutation in the C2H2 zinc finger transcription factor-encoding gene GFC1 (Gfc1 variants). Deletion of GFC1 leads to an RL-FC phenotype similar to that observed in Gfc1 variants. We further demonstrate that GFC1 mutation causes enhanced fatty acid ß-oxidation metabolism and thereby promotes RL-FC/filamentous growth. This regulation is achieved through a Multiple Carbon source Utilizer (Mcu1)-dependent mechanism. Interestingly, both the evolved RL-FC isolates and the gfc1Δ mutant exhibit an enhanced ability to colonize the skin. Our results reveal that glycerol-mediated GFC1 mutations are beneficial during C. auris skin colonization and infection.


Assuntos
Candida auris , Candidíase , Proteínas Fúngicas , Mutação , Candidíase/microbiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Candida auris/genética , Candida auris/metabolismo , Camundongos , Animais , Glicerol/metabolismo , Adaptação Fisiológica , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Regulação Fúngica da Expressão Gênica , Humanos
2.
Plant Cell ; 35(1): 453-468, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36190337

RESUMO

RAC/Rho of plant (ROP) GTPases are major molecular switches that control diverse signaling cascades for plant growth, development, and defense. Here, we discovered a signaling node that connects RAC/ROPs to cytokinins. Rice (Oryza sativa) plants develop a fibrous root system mainly composed of crown roots. Cytokinin signaling via a phosphorelay system is critical for crown root development. We show that OsRopGEF10, which activates RAC/ROPs, acts upstream of the cytoplasmic-nuclear shuttling phosphotransfer proteins AHPs of the cytokinin signaling pathway to promote crown root development. Mutations of OsRopGEF10 induced hypersensitivity to cytokinin, whereas overexpressing this gene reduced the cytokinin response. Loss of OsRopGEF10 function reduced the expression of the response regulator gene OsRR6, a repressor of cytokinin signaling, and impaired crown root development. Mutations in OsAHP1/2 led to increased crown root production and rescued the crown root defect of Osropgef10. Furthermore, auxin activates the ROP GTPase OsRAC3, which attenuates cytokinin signaling for crown root initiation. Molecular interactions between OsRopGEF10, OsRAC3, and OsAHP1/2 implicate a mechanism whereby OsRopGEF10-activated OsRAC3 recruits OsAHP1/2 to the cortical cytoplasm, sequestering them from their phosphorelay function in the nucleus. Together, our findings uncover the OsRopGEF10-OsRAC3-OsAHP1/2 signaling module, establish a link between RAC/ROPs and cytokinin, and reveal molecular crosstalk between auxin and cytokinin during crown root development.


Assuntos
Oryza , Oryza/metabolismo , Ativadores de GTP Fosfo-Hidrolase/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Transdução de Sinais , Citocininas/metabolismo , Ácidos Indolacéticos/metabolismo , Regulação da Expressão Gênica de Plantas
3.
PLoS Biol ; 21(12): e3002421, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38048304

RESUMO

Neuronal development orchestrates the formation of an enormous number of synapses that connect the nervous system. In developing presynapses, the core active zone structure has been found to assemble through liquid-liquid phase separation. Here, we find that the phase separation of Caenorhabditis elegans SYD-2/Liprin-α, a key active zone scaffold, is controlled by phosphorylation. We identify the SAD-1 kinase as a regulator of SYD-2 phase separation and determine presynaptic assembly is impaired in sad-1 mutants and increased by overactivation of SAD-1. Using phosphoproteomics, we find SAD-1 phosphorylates SYD-2 on 3 sites that are critical to activate phase separation. Mechanistically, SAD-1 phosphorylation relieves a binding interaction between 2 folded domains in SYD-2 that inhibits phase separation by an intrinsically disordered region (IDR). We find synaptic cell adhesion molecules localize SAD-1 to nascent synapses upstream of active zone formation. We conclude that SAD-1 phosphorylates SYD-2 at developing synapses, activating its phase separation and active zone assembly.


Assuntos
Proteínas de Caenorhabditis elegans , Terminações Pré-Sinápticas , Animais , Terminações Pré-Sinápticas/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Sinapses/metabolismo , Caenorhabditis elegans/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo
4.
Proc Natl Acad Sci U S A ; 120(27): e2300625120, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37364101

RESUMO

The dehydrogenation reaction of bioderived ethanol is of particular interest for the synthesis of fuels and value-added chemicals. However, this reaction historically suffered from high energy consumption (>260 °C or >0.8 V) and low efficiency. Herein, the efficient conversion of alcohol to hydrogen and aldehyde is achieved by integrating the thermal dehydrogenation reaction with electrochemical hydrogen transfer at low temperature (120 °C) and low voltage (0.06 V), utilizing a bifunctional catalyst (Ru/C) with both thermal-catalytic and electrocatalytic activities. Specifically, the coupled electrochemical hydrogen separation procedure can serve as electrochemical hydrogen pumps, which effectively promote the equilibrium of ethanol dehydrogenation toward hydrogen and acetaldehyde production and simultaneously purifies hydrogen at the cathode. By utilizing this strategy, we achieved boosted hydrogen and acetaldehyde yields of 1,020 mmol g-1 h-1 and 1,185 mmol g-1 h-1, respectively, which are threefold higher than the exclusive ethanol thermal dehydrogenation. This work opens up a prospective route for the high-efficiency production of hydrogen and acetaldehyde via coupled thermal-electrocatalysis.

5.
FASEB J ; 38(3): e23453, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38318639

RESUMO

During early development, both genome-wide epigenetic reprogramming and metabolic remodeling are hallmark changes of normal embryogenesis. However, little is known about their relationship and developmental functions during the preimplantation window, which is essential for the acquisition of totipotency and pluripotency. Herein, we reported that glutathione (GSH), a ubiquitous intracellular protective antioxidant that maintains mitochondrial function and redox homeostasis, plays a critical role in safeguarding postfertilization DNA demethylation and is essential for establishing developmental potential in preimplantation embryos. By profiling mitochondria-related transcriptome that coupled with different pluripotency, we found GSH is a potential marker that is tightly correlated with full pluripotency, and its beneficial effect on prompting developmental potential was functionally conformed using in vitro fertilized mouse and bovine embryos as the model. Mechanistic study based on preimplantation embryos and embryonic stem cells further revealed that GSH prompts the acquisition of totipotency and pluripotency by facilitating ten-eleven-translocation (TET)-dependent DNA demethylation, and ascorbic acid (AsA)-GSH cycle is implicated in the process. In addition, we also reported that GSH serves as an oviductal paracrine factor that supports development potential of preimplantation embryos. Thus, our results not only advance the current knowledge of functional links between epigenetic reprogramming and metabolic remodeling during preimplantation development but also provided a promising approach for improving current in vitro culture system for assisted reproductive technology.


Assuntos
Desmetilação do DNA , Metilação de DNA , Animais , Bovinos , Camundongos , Blastocisto/metabolismo , Células-Tronco Embrionárias/metabolismo , Glutationa/metabolismo , Desenvolvimento Embrionário/genética
6.
Clin Infect Dis ; 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38484128

RESUMO

BACKGROUND: Oral pre-exposure prophylaxis (PrEP) with emtricitabine/tenofovir disoproxil fumarate (F/TDF) has high efficacy against HIV-1 acquisition. Seventy-two prospective studies of daily oral F/TDF PrEP were conducted to evaluate HIV-1 incidence, drug resistance, adherence, and bone and renal safety in diverse settings. METHODS: HIV-1 incidence was calculated from incident HIV-1 diagnoses after PrEP initiation and within 60 days of discontinuation. Tenofovir concentration in dried blood spots (DBS), drug resistance, and bone/renal safety indicators were evaluated in a subset of studies. RESULTS: Among 17,274 participants, there were 101 cases with new HIV-1 diagnosis (0.77 per 100 person-years; 95% CI 0.63-0.94). In 78 cases with resistance data, 18 (23%) had M184I or V, one (1.3%) had K65R, and three (3.8%) had both mutations. In 54 cases with tenofovir concentration data from DBS, 45 (83.3%), 2 (3.7%), 6 (11.1%), and 1 (1.9%) had average adherence of <2, 2-3, 4-6, and ≥7 doses/week, respectively, and the corresponding incidence was 3.9 (95% CI 2.9-5.3), 0.24 (0.060-0.95), 0.27 (0.12-0.60), and 0.054 (0.008-0.38) per 100 person-years. Adherence was low in younger participants, Hispanic/Latinx and Black participants, cisgender women, and transgender women. Bone and renal adverse event incidence rates were 0.69 and 11.8 per 100 person-years, respectively, consistent with previous reports. CONCLUSIONS: Leveraging the largest pooled analysis of global PrEP studies to date, we demonstrate that F/TDF is safe and highly effective, even with less than daily dosing, in diverse clinical settings, geographies, populations, and routes of HIV-1 exposure.

7.
J Am Chem Soc ; 146(14): 9657-9664, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38557037

RESUMO

Hydrogen production from methanol represents an energy-sustainable way to produce ethanol, but it normally results in heavy CO2 emissions. The selective conversion of methanol into H2 and valuable chemical feedstocks offers a promising strategy; however, it is limited by the harsh operating conditions and low conversion efficiency. Herein, we realize efficient high-purity H2 and CO production from methanol by coupling the thermocatalytic methanol dehydrogenation with electrocatalytic hydrogen oxidation on a bifunctional Ru/C catalyst. Electrocatalysis enables the acceleration of C-H cleavage and reduces the partial pressure of hydrogen at the anode, which drives the chemical equilibrium and significantly enhances methanol dehydrogenation. Furthermore, a bilayer Ru/C + Pd/C electrode is designed to mitigate CO poisoning and facilitate hydrogen oxidation. As a result, a high yield of H2 (558.54 mmol h-1 g-1) with high purity (99.9%) was achieved by integrating an applied cell voltage of 0.4 V at 200 °C, superior to the conventional thermal and electrocatalytic processes, and CO is the main product at the anode. This work presents a new avenue for efficient H2 production together with valuable chemical synthesis from methanol.

8.
EMBO J ; 39(2): e100789, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31849090

RESUMO

Accurate chromosome segregation in mitosis requires sister kinetochores to bind to microtubules from opposite spindle poles. The stability of kinetochore-microtubule attachments is fine-tuned to prevent or correct erroneous attachments while preserving amphitelic interactions. Polo kinase has been implicated in both stabilizing and destabilizing kinetochore-microtubule attachments. However, the mechanism underlying Polo-destabilizing activity remains elusive. Here, resorting to an RNAi screen in Drosophila for suppressors of a constitutively active Polo mutant, we identified a strong genetic interaction between Polo and the Rod-ZW10-Zwilch (RZZ) complex, whose kinetochore accumulation has been shown to antagonize microtubule stability. We find that Polo phosphorylates Spindly and impairs its ability to bind to Zwilch. This precludes dynein-mediated removal of the RZZ from kinetochores and consequently delays the formation of stable end-on attachments. We propose that high Polo-kinase activity following mitotic entry directs the RZZ complex to minimize premature stabilization of erroneous attachments, whereas a decrease in active Polo in later mitotic stages allows the formation of stable amphitelic spindle attachments. Our findings demonstrate that Polo tightly regulates the RZZ-Spindly-dynein module during mitosis to ensure the fidelity of chromosome segregation.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/fisiologia , Cinetocoros/metabolismo , Microtúbulos/metabolismo , Mitose , Proteínas Serina-Treonina Quinases/metabolismo , Fuso Acromático , Animais , Proteínas de Ciclo Celular/metabolismo , Segregação de Cromossomos , Dineínas/metabolismo , Feminino , Cinetocoros/química , Masculino , Microtúbulos/química , Transdução de Sinais
9.
Mol Med ; 30(1): 50, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622518

RESUMO

BACKGROUND: Colorectal cancer standed as a global health challenge, ranking third in cancer incidence and second in cancer-related deaths worldwide. A deeper understanding of the intricate mechanisms driving colorectal cancer development was pressing need. STK16 had garnered attention in recent researches, while its involvement in cancer had been minimally explored. c-MYC had emerged as a key player in cancer biology. Due to its complex structure, multifunctionality, and intricate interactions, directly inhibiting the activity of c-MYC proves to be challenging. Hence, current research was directing efforts towards modulating c-MYC expression levels. METHODS: Immunoblot, Immunohistochemistry and immunoprecipitation assays were conducted to assess the indicated protein expression levels. RT-PCR was performed to detect the corresponding mRNA expression levels. The proliferation, migration, invasion, and colony formation abilities of the specified cancer cells were investigated using CCK8 assays, Brdu assays, transwell assays, and colony formation assays, respectively. Cellular and animal experiments were performed to investigate the correlation between STK16 signaling and c-MYC signaling. RESULTS: STK16 plays a positive regulatory role in the progression of colorectal cancer. Delving into the molecular mechanisms, we unveiled that STK16 phosphorylated c-MYC at serine 452, a pivotal event hindering the ubiquitin-proteasome pathway degradation of c-MYC. Importantly, colorectal cancer proliferation mediated by STK16 was found to be dependent on the phosphorylation of c-MYC at S452. Furthermore, the researchers demonstrated that STK16 knockout or pharmacological inhibition significantly curtailed colorectal cancer proliferation and c-MYC expression in in vivo animal models. CONCLUSION: We discovered that STK16 phosphorylates c-MYC at serine 452, hindering its degradation via the ubiquitin-proteasome pathway. STK16 inhibition, either genetically or pharmacologically, effectively curtails cancer growth and c-MYC expression in vivo. These findings highlight STK16 as a potential therapeutic target for colorectal cancer.


Assuntos
Neoplasias Colorretais , Transdução de Sinais , Animais , Humanos , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/metabolismo , Regulação Neoplásica da Expressão Gênica , Fosforilação , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Serina/metabolismo , Ubiquitinas/genética
10.
Anal Chem ; 96(24): 10003-10012, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38853531

RESUMO

Fc-fusion proteins are an emerging class of protein therapeutics that combine the properties of biological ligands with the unique properties of the fragment crystallizable (Fc) domain of an immunoglobulin G (IgG). Due to their diverse higher-order structures (HOSs), Fc-fusion proteins remain challenging characterization targets within biopharmaceutical pipelines. While high-resolution biophysical tools are available for HOS characterization, they frequently demand extended time frames and substantial quantities of purified samples, rendering them impractical for swiftly screening candidate molecules. Herein, we describe the development of ion mobility-mass spectrometry (IM-MS) and collision-induced unfolding (CIU) workflows that aim to fill this technology gap, where we focus on probing the HOS of a model Fc-Interleukin-10 (Fc-IL-10) fusion protein engineered using flexible glycine-serine linkers. We evaluate the ability of these techniques to probe the flexibility of Fc-IL-10 in the absence of bulk solvent relative to other proteins of similar size, as well as localize structural changes of low charge state Fc-IL-10 ions to specific Fc and IL-10 unfolding events during CIU. We subsequently apply these tools to probe the local effects of glycine-serine linkers on the HOS and stability of IL-10 homodimer, which is the biologically active form of IL-10. Our data reveals that Fc-IL-10 produces significantly more structural transitions during CIU and broader IM profiles when compared to a wide range of model proteins, indicative of its exceptional structural dynamism. Furthermore, we use a combination of enzymatic approaches to annotate these intricate CIU data and localize specific transitions to the unfolding of domains within Fc-IL-10. Finally, we detect a strong positive, quadratic relationship between average linker mass and fusion protein stability, suggesting a cooperative influence between glycine-serine linkers and overall fusion protein stability. This is the first reported study on the use of IM-MS and CIU to characterize HOS of Fc-fusion proteins, illustrating the practical applicability of this approach.


Assuntos
Fragmentos Fc das Imunoglobulinas , Espectrometria de Massas , Desdobramento de Proteína , Proteínas Recombinantes de Fusão , Fragmentos Fc das Imunoglobulinas/química , Proteínas Recombinantes de Fusão/química , Espectrometria de Massas/métodos , Interleucina-10/química , Interleucina-10/metabolismo , Espectrometria de Mobilidade Iônica/métodos , Estabilidade Proteica , Humanos , Imunoglobulina G/química
11.
Small ; 20(26): e2311205, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38267814

RESUMO

Urea, as one of the most sustainable organic solutes, denies the high salt consumption in commercial electrolytes with its peculiar solubility in water. The bi-mixture of urea-H2O shows the eutectic feature for increased attention in aqueous Zn-ion electrochemical energy storage (AZEES) technologies. While the state-of-the-art aqueous electrolyte recipes are still pursuing the high-concentrated salt dosage with limited urea adoption and single-anion selection category. Here, a dual-anion urea-based (DAU) electrolyte composed of dual-Zn salts and urea-H2O-induced solutions is reported, contributing to a stable electric double-layer construction and in situ organic/inorganic SEI formation. The optimized ZT2S0.5-20U electrolytes show a high initial Coulombic efficiency of 93.2% and durable Zn-ion storage ≈4000 h regarding Zn//Cu and Zn//Zn stripping/plating procedures. The assembled Zn//activated carbon full cells maintain ≈100% capacitance over 50 000 cycles at 4 A g-1 in coin cell and ≈98% capacitance over 20 000 cycles at 1 A g-1 in pouch cell setups. A 12 × 12 cm2 pouch cell assembly illustrates the practicality of AZEES devices by designing the cheap, antifreezing, and nonflammable DAU electrolyte system coupling proton donor-acceptor molecule and multi-anion selection criteria, exterminating the critical technical barriers in commercialization.

12.
Cancer Causes Control ; 35(5): 799-815, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38206498

RESUMO

PURPOSE: One in six incident cancers in the U.S. is a second primary cancer (SPC). Although primary cancers vary considerably by race and ethnicity, little is known about the population-based occurrence of SPC across these groups. METHODS: Using Surveillance, Epidemiology, and End Results (SEER) 12 data and relative to the general population, we calculated standardized incidence ratios (SIRs) and 95% confidence intervals (CIs) for SPC among 2,457,756 Hispanics, non-Hispanic Asian American/Pacific Islanders (NHAAPI), non-Hispanic black (NHB), and non-Hispanic whites (NHW) cancer survivors aged 45 years or older when diagnosed with a first primary cancer (FPC) from 1992 to 2015. RESULTS: The risk of second primary bladder cancer after first primary prostate cancer was higher than expected in Hispanic (SIR = 1.18, 95% CI: 1.01-1.38) and NHAAPI (SIR = 1.41, 95% CI: 1.20-1.65) men than NHB and NHW men. Among women with a primary breast cancer, Hispanic, NHAAPI, and NHB women had a nearly 1.5-fold higher risk of a second primary breast cancer, while NHW women had a 6% lower risk. Among men with prostate cancer whose SPC was diagnosed 2 to <12 months, NHB men were at higher risk for colorectal cancer and Hispanic and NHW men for non-Hodgkin's lymphoma. In the same time frame for breast cancer survivors, Hispanic and NHAAPI women were significantly more likely than NHB and NHW women to be diagnosed with a second primary lung cancer. CONCLUSION: Future studies of SPC should investigate the role of shared etiologies, stage of diagnosis, treatment, and lifestyle factors after cancer survival across different racial and ethnic populations.


Assuntos
Etnicidade , Segunda Neoplasia Primária , Programa de SEER , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sobreviventes de Câncer/estatística & dados numéricos , Etnicidade/estatística & dados numéricos , Incidência , Segunda Neoplasia Primária/epidemiologia , Segunda Neoplasia Primária/etnologia , Grupos Raciais/estatística & dados numéricos , Fatores de Risco , Estados Unidos/epidemiologia , Hispânico ou Latino , Nativo Asiático-Americano do Havaí e das Ilhas do Pacífico , Negro ou Afro-Americano , Brancos
13.
Ann Rheum Dis ; 83(1): 121-132, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37666645

RESUMO

OBJECTIVES: To provide an overview and in-depth analysis of temporal trends in prevalence of musculoskeletal (MSK) disorders in women of childbearing age (WCBA) at global, regional and national levels over the last 30 years, with a special focus on their associations with age, period and birth cohort. METHODS: Estimates and 95% uncertainty intervals (UIs) for MSK disorders prevalence in WCBA were extracted from the Global Burden of Diseases, Injuries and Risk Factors Study 2019. An age-period-cohort model was adopted to estimate the overall annual percentage change of prevalence (net drift, % per year), annual percentage change of prevalence within each age group (local drift, % per year), fitted longitudinal age-specific rates adjusted for period deviations (age effects) and period/cohort relative risks (period/cohort effects) from 1990 to 2019. RESULTS: In 2019, the global number of MSK disorders prevalence in WCBA was 354.57 million (95% UI: 322.64 to 387.68). Fifty countries had at least one million prevalence, with India, China, the USA, Indonesia and Brazil being the highest accounting for 51.03% of global prevalence. From 1990 to 2019, a global net drift of MSK disorders prevalence in WCBA was -0.06% (95% CI: -0.07% to -0.05%) per year, ranging from -0.09% (95% CI: -0.10% to -0.07%) in low-middle sociodemographic index (SDI) region to 0.10% (95% CI: 0.08% to 0.12%) in high-middle SDI region, with 138 countries presenting increasing trends, 24 presenting decreasing trends and 42 presenting relatively flat trends. As reflected by local drift, higher SDI regions had more age groups showing rising prevalence whereas lower SDI regions had more declining prevalence. Globally, an increasing occurrence of MSK disorders prevalence in WCBA beyond adolescent and towards the adult stage has been prominent. Age effects illustrated similar patterns across different SDI regions, with risk increasing with age. High SDI region showed generally lower period risks over time, whereas others showed more unfavourable period risks. High, high-middle and middle SDI regions presented unfavourable prevalence deteriorations, whereas others presented favourable prevalence improvements in successively birth cohorts. CONCLUSIONS: Although a favourable overall temporal trend (net drift) of MSK disorders prevalence in WCBA was observed over the last 30 years globally, there were 138 countries showing unfavourable rising trends, coupled with deteriorations in period/cohort risks in many countries, collectively raising concerns about timely realisation of the Targets of Sustainable Development Goal. Improvements in the MSK disorders-related prevention, management and treatment programmes in WCBA could decline the relative risk for successively younger birth cohorts and for all age groups over period progressing.


Assuntos
Carga Global da Doença , Doenças Musculoesqueléticas , Adulto , Adolescente , Humanos , Feminino , Prevalência , Fatores de Risco , Estudos de Coortes , Doenças Musculoesqueléticas/epidemiologia , Saúde Global , Anos de Vida Ajustados por Qualidade de Vida , Incidência
14.
Opt Express ; 32(6): 8623-8637, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571117

RESUMO

In fiber-terahertz integrated communication systems, nonlinear distortion and inter-symbol interference (ISI) will degrade transmission performance. Pre-compensation is an efficient method to handle the channel distortion as it can avoid noise boosting during channel compensation and reduce receiver side signal processing algorithmic complexity at user-end (UE) considering the asymmetric access scenario. In this paper, we propose and experimentally demonstrate a neural-network (NN)-based carrier-less amplitude phase (CAP) modulated signal generation and end-to-end optimization method for a fiber-terahertz integrated communication system. The CAP signal is generated directly from quadrature amplitude modulation symbols and pre-compensated through a transmitter NN, which allows the receiver to demodulate the signal with simple linear digital signal process (DSP). In generating the CAP signal, the NN based transmitter learns a group of filters, which can generate, up-convert, and pre-compensate the signals. Based on the proposed method, a fiber-terahertz integration access system at 220 GHz is demonstrated and a sensitivity gain of 1.2 dB is achieved at a transmission speed of 50 Gbps and the forward error correction (FEC) bit error rate (BER) threshold of 1 × 10-2 compared with the baseline after 10-km fiber transmission and 1-m wireless delivering.

15.
Toxicol Appl Pharmacol ; 486: 116914, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522585

RESUMO

Ferroptosis has been shown to be involved in carbon tetrachloride (CCl4)-induced acute liver injury (ALI). The mitochondrion-targeted antioxidant MitoQ can eliminate the production of mitochondrial reactive oxygen species (mtROS). This study investigated the role of MitoQ in CCl4-induced hepatocytic ferroptosis and ALI. MDA and 4HNE were elevated in CCl4-induced mice. In vitro, CCl4 exposure elevated the levels of oxidized lipids in HepG2 cells. Alterations in the mitochondrial ultrastructure of hepatocytes were observed in the livers of CCl4-evoked mice. Ferrostatin-1 (Fer-1) attenuated CCl4-induced hepatic lipid peroxidation, mitochondrial ultrastructure alterations and ALI. Mechanistically, acyl-CoA synthetase long-chain family member 4 (ACSL4) was upregulated in CCl4-exposed human hepatocytes and mouse livers. The ACSL4 inhibitor rosiglitazone alleviated CCl4-induced hepatic lipid peroxidation and ALI. ACSL4 knockdown inhibited oxidized lipids in CCl4-exposed human hepatocytes. Moreover, CCl4 exposure decreased the mitochondrial membrane potential and OXPHOS subunit levels and increased the mtROS level in HepG2 cells. Correspondingly, MitoQ pretreatment inhibited the upregulation of ACSL4 in CCl4-evoked mouse livers and HepG2 cells. MitoQ attenuated lipid peroxidation in vivo and in vitro after CCl4 exposure. Finally, MitoQ pretreatment alleviated CCl4-induced hepatocytic ferroptosis and ALI. These findings suggest that MitoQ protects against hepatocyte ferroptosis in CCl4-induced ALI via the mtROS-ACSL4 pathway.


Assuntos
Tetracloreto de Carbono , Doença Hepática Induzida por Substâncias e Drogas , Coenzima A Ligases , Ferroptose , Hepatócitos , Camundongos Endogâmicos C57BL , Compostos Organofosforados , Espécies Reativas de Oxigênio , Regulação para Cima , Animais , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Regulação para Cima/efeitos dos fármacos , Células Hep G2 , Coenzima A Ligases/metabolismo , Coenzima A Ligases/genética , Camundongos , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Doença Hepática Induzida por Substâncias e Drogas/patologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Ferroptose/efeitos dos fármacos , Tetracloreto de Carbono/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Masculino , Compostos Organofosforados/farmacologia , Ubiquinona/análogos & derivados , Ubiquinona/farmacologia , Antioxidantes/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos
16.
Chemistry ; 30(40): e202400907, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38649319

RESUMO

Hybrid supercapacitors (HSCs) bridge the unique advantages of batteries and capacitors and are considered promising energy storage devices for hybrid vehicles and other electronic gadgets. Lithium-ion capacitors (LICs) have attained particular interest due to their higher energy and power density than traditional supercapacitor devices. The limited voltage window and the deterioration of anode materials upsurged the demand for efficient and stable electrode materials. Two-dimensional (2D) molybdenum sulfide (MoS2) is a promising candidate for developing efficient and durable LICs due to its wide lithiation potential and unique layer structure, enhancing charge storage efficiency. Modifying the extrinsic features, such as the dimensions and shape at the nanoscale, serves as a potential path to overcome the sluggish kinetics observed in the LICs. Herein, the MoS2 nanoflowers have been synthesized through a hydrothermal route. The developed LIC exhibited a specific capacitance of 202.4 F g-1 at 0.25 A g-1 and capacitance retention of >90 % over 5,000 cycles. Using an ether electrolyte improved the voltage window (2.0 V) and enhanced the stability performance. The ex-situ material characterization after the stability test reveals that the storage mechanism in MoS2-LICs is not diffusion-controlled. Instead, the fast surface redox reactions, especially intercalation/deintercalation of ions, are more prominent for charge storage.

17.
Pharmacol Res ; 201: 107091, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38316371

RESUMO

Inhibition of checkpoint kinase 1 (Chk1) has shown to overcome resistance to poly (ADP-ribose) polymerase (PARP) inhibitors and expand the clinical utility of PARP inhibitors in a broad range of human cancers. Pristimerin, a naturally occurring pentacyclic triterpenoid, has been the focus of intensive studies for its anticancer potential. However, it is not yet known whether low dose of pristimerin can be combined with PARP inhibitors by targeting Chk1 signaling pathway. In this study, we investigated the efficacy, safety and molecular mechanisms of the synergistic effect produced by the combination olaparib and pristimerin in TP53-deficient and BRCA-proficient cell models. As a result, an increased expression of Chk1 was correlated with TP53 mutation, and pristimerin preferentially sensitized p53-defective cells to olaparib. The combination of olaparib and pristimerin resulted in a more pronounced abrogation of DNA synthesis and induction of DNA double-strand breaks (DSBs). Moreover, pristimerin disrupted the constitutional levels of Chk1 and DSB repair activities. Mechanistically, pristimerin promoted K48-linked polyubiquitination and proteasomal degradation of Chk1 while not affecting its kinase domain and activity. Importantly, combinatorial therapy led to a higher rate of tumor growth inhibition without apparent hematological toxicities. In addition, pristimerin suppressed olaparib-induced upregulation of Chk1 and enhanced olaparib-induced DSB marker γΗ2ΑΧ in vivo. Taken together, inhibition of Chk1 by pristimerin has been observed to induce DNA repair deficiency, which may expand the application of olaparib in BRCA-proficient cancers harboring TP53 mutations. Thus, pristimerin can be combined for PARP inhibitor-based therapy.


Assuntos
Antineoplásicos , Triterpenos , Humanos , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Quinase 1 do Ponto de Checagem/metabolismo , Triterpenos/farmacologia , Triterpenos/uso terapêutico , Proteína Supressora de Tumor p53/metabolismo , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Triterpenos Pentacíclicos , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Ubiquitinação , DNA
18.
J Immunol ; 208(7): 1595-1615, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35304419

RESUMO

IL-22 is a multifaceted cytokine with both pro- and anti-inflammatory functions that is implicated in multiple pathologies. However, the role of IL-22 in maternal-fetal immunity in late gestation is poorly understood. In this study, we first showed that IL-22+ T cells coexpressing retinoic acid-related orphan receptor γt (ROR-γt) are enriched at the human maternal-fetal interface of women with preterm labor and birth, which was confirmed by in silico analysis of single-cell RNA sequencing data. T cell activation leading to preterm birth in mice was preceded by a surge in IL-22 in the maternal circulation and amniotic cavity; however, systemic administration of IL-22 in mice did not induce adverse perinatal outcomes. Next, using an ex vivo human system, we showed that IL-22 can cross from the choriodecidua to the intra-amniotic space, where its receptors (Il22ra1, Il10rb, and Il22ra2) are highly expressed by murine gestational and fetal tissues in late pregnancy. Importantly, amniotic fluid concentrations of IL-22 were elevated in women with sterile or microbial intra-amniotic inflammation, suggesting a dual role for this cytokine. The intra-amniotic administration of IL-22 alone shortened gestation and caused neonatal death in mice, with the latter outcome involving lung maturation and inflammation. IL-22 plays a role in host response by participating in the intra-amniotic inflammatory milieu preceding Ureaplasma parvum-induced preterm birth in mice, which was rescued by the deficiency of IL-22. Collectively, these data show that IL-22 alone is capable of causing fetal injury leading to neonatal death and can participate in host defense against microbial invasion of the amniotic cavity leading to preterm labor and birth.


Assuntos
Trabalho de Parto Prematuro , Nascimento Prematuro , Líquido Amniótico , Animais , Feminino , Humanos , Recém-Nascido , Interleucinas/metabolismo , Camundongos , Gravidez , Nascimento Prematuro/metabolismo , Receptores de Interleucina/metabolismo , Interleucina 22
19.
J Immunol ; 208(8): 1857-1872, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35379748

RESUMO

Pregnant women are at increased risk of adverse outcomes, including preeclampsia and preterm birth, that may result from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Pregnancy imprints specific maternal immune responses that can modulate host susceptibility to microbial infection; therefore, recent studies have focused on the humoral response against SARS-CoV-2 in pregnant women. However, the pregnancy-specific cellular immune responses triggered by SARS-CoV-2 infection are poorly understood. In this study, we undertook an extensive in vitro investigation to determine the cellular immune responses to SARS-CoV-2 particles and proteins/peptides in pregnant women. First, we show that SARS-CoV-2 particles do not alter the pregnancy-specific oxidative burst of neutrophils and monocytes. Yet, SARS-CoV-2 particles/proteins shift monocyte activation from the classical to intermediate states in pregnant, but not in nonpregnant, women. Furthermore, SARS-CoV-2 proteins, but not particles or peptide pools, mildly enhance T cell activation during pregnancy. As expected, B cell phenotypes are heavily modulated by SARS-CoV-2 particles in all women; yet, pregnancy itself further modified such responses in these adaptive immune cells. Lastly, we report that pregnancy itself governs cytokine responses in the maternal circulation, of which IFN-ß and IL-8 were diminished upon SARS-CoV-2 challenge. Collectively, these findings highlight the differential in vitro responses to SARS-CoV-2 in pregnant and nonpregnant women and shed light on the immune mechanisms implicated in coronavirus disease 2019 during pregnancy.


Assuntos
COVID-19 , Complicações Infecciosas na Gravidez , Nascimento Prematuro , Feminino , Humanos , Imunidade Celular , Recém-Nascido , Gravidez , Resultado da Gravidez , Gestantes , SARS-CoV-2
20.
Environ Res ; 257: 119267, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38815718

RESUMO

Natural pyrethrins are widely used in agriculture because of their good insecticidal activity. Meanwhile, natural pyrethrins play an important role in the safety evaluation of pyrethroids as precursors for structural development of pyrethroid insecticides. However, there are fewer studies evaluating the neurological safety of natural pyrethrins on non-target organisms. In this study, we used SH-SY5Y cells and zebrafish embryos to explore the neurotoxicity of natural pyrethrins. Natural pyrethrins were able to induce SH-SY5Y cells damage, as evidenced by decreased viability, cycle block, apoptosis and DNA damage. The apoptotic pathway may be related to the involvement of mitochondria and the results showed that natural pyrethrins induced a rise in Capase-3 viability, Ca2+ overload, a decrease in adenosine triphosphate (ATP) and a collapse of mitochondrial membrane potential in SH-SY5Y cells. Natural pyrethrins may mediate DNA damage in SH-SY5Y cells through oxidative stress. The results showed that natural pyrethrins induced an increase in reactive oxygen species (ROS) levels, superoxide dismutase (SOD) activity, malondialdehyde (MDA) content and catalase (CAT) activity, and induced a decrease in glutathione peroxidase (GPx) activity in SH-SY5Y cells. In vivo, natural pyrethrins induced developmental malformations in zebrafish embryos, which were mainly characterized by pericardial edema and yolk sac edema. Meanwhile, the results showed that natural pyrethrins induced damage to the Huc-GFP axis and disturbed lipid metabolism in the head of zebrafish embryos. Further results showed elevated ROS levels and apoptosis in the head of zebrafish embryos, which corroborated with the results of the cell model. Finally, the results of mRNA expression assay of neurodevelopment-related genes indicated that natural pyrethrins exposure interfered with their expression and led to neurodevelopmental damage in zebrafish embryos. Our study may raise concerns about the neurological safety of natural pyrethrins on non-target organisms.


Assuntos
Embrião não Mamífero , Piretrinas , Peixe-Zebra , Animais , Peixe-Zebra/embriologia , Piretrinas/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Humanos , Espécies Reativas de Oxigênio/metabolismo , Apoptose/efeitos dos fármacos , Inseticidas/toxicidade , Dano ao DNA/efeitos dos fármacos , Linhagem Celular Tumoral , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos
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