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1.
J Pharm Pharm Sci ; 27: 12434, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38571937

RESUMEN

Microneedle (MN)-assisted drug delivery technology has gained increasing attention over the past two decades. Its advantages of self-management and being minimally invasive could allow this technology to be an alternative to hypodermic needles. MNs can penetrate the stratum corneum and deliver active ingredients to the body through the dermal tissue in a controlled and sustained release. Long-acting polymeric MNs can reduce administration frequency to improve patient compliance and therapeutic outcomes, especially in the management of chronic diseases. In addition, long-acting MNs could avoid gastrointestinal reactions and reduce side effects, which has potential value for clinical application. In this paper, advances in design strategies and applications of long-acting polymeric MNs are reviewed. We also discuss the challenges in scale manufacture and regulations of polymeric MN systems. These two aspects will accelerate the effective clinical translation of MN products.


Asunto(s)
Sistemas de Liberación de Medicamentos , Piel , Humanos , Microinyecciones , Administración Cutánea , Preparaciones Farmacéuticas , Polímeros
2.
BMC Med ; 21(1): 464, 2023 11 27.
Artículo en Inglés | MEDLINE | ID: mdl-38012705

RESUMEN

BACKGROUND: Post-radiation nasopharyngeal necrosis (PRNN) is a severe adverse event following re-radiotherapy for patients with locally recurrent nasopharyngeal carcinoma (LRNPC) and associated with decreased survival. Biological heterogeneity in recurrent tumors contributes to the different risks of PRNN. Radiomics can be used to mine high-throughput non-invasive image features to predict clinical outcomes and capture underlying biological functions. We aimed to develop a radiogenomic signature for the pre-treatment prediction of PRNN to guide re-radiotherapy in patients with LRNPC. METHODS: This multicenter study included 761 re-irradiated patients with LRNPC at four centers in NPC endemic area and divided them into training, internal validation, and external validation cohorts. We built a machine learning (random forest) radiomic signature based on the pre-treatment multiparametric magnetic resonance images for predicting PRNN following re-radiotherapy. We comprehensively assessed the performance of the radiomic signature. Transcriptomic sequencing and gene set enrichment analyses were conducted to identify the associated biological processes. RESULTS: The radiomic signature showed discrimination of 1-year PRNN in the training, internal validation, and external validation cohorts (area under the curve (AUC) 0.713-0.756). Stratified by a cutoff score of 0.735, patients with high-risk signature had higher incidences of PRNN than patients with low-risk signature (1-year PRNN rates 42.2-62.5% vs. 16.3-18.8%, P < 0.001). The signature significantly outperformed the clinical model (P < 0.05) and was generalizable across different centers, imaging parameters, and patient subgroups. The radiomic signature had prognostic value concerning its correlation with PRNN-related deaths (hazard ratio (HR) 3.07-6.75, P < 0.001) and all causes of deaths (HR 1.53-2.30, P < 0.01). Radiogenomics analyses revealed associations between the radiomic signature and signaling pathways involved in tissue fibrosis and vascularity. CONCLUSIONS: We present a radiomic signature for the individualized risk assessment of PRNN following re-radiotherapy, which may serve as a noninvasive radio-biomarker of radiation injury-associated processes and a useful clinical tool to personalize treatment recommendations for patients with LANPC.


Asunto(s)
Neoplasias Nasofaríngeas , Recurrencia Local de Neoplasia , Humanos , Carcinoma Nasofaríngeo/genética , Estudios Retrospectivos , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/genética , Pronóstico , Neoplasias Nasofaríngeas/diagnóstico por imagen , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/radioterapia , Imagen por Resonancia Magnética/métodos
3.
New Phytol ; 237(1): 126-139, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36128660

RESUMEN

The model heterocyst-forming filamentous cyanobacterium Anabaena sp. PCC 7120 (Anabaena) is a typical example of a multicellular organism capable of simultaneously performing oxygenic photosynthesis in vegetative cells and O2 -sensitive N2 -fixation inside heterocysts. The flavodiiron proteins have been shown to participate in photoprotection of photosynthesis by driving excess electrons to O2 (a Mehler-like reaction). Here, we performed a phenotypic and biophysical characterization of Anabaena mutants impaired in vegetative-specific Flv1A and Flv3A in order to address their physiological relevance in the bioenergetic processes occurring in diazotrophic Anabaena under variable CO2 conditions. We demonstrate that both Flv1A and Flv3A are required for proper induction of the Mehler-like reaction upon a sudden increase in light intensity, which is likely important for the activation of carbon-concentrating mechanisms and CO2 fixation. Under ambient CO2 diazotrophic conditions, Flv3A is responsible for moderate O2 photoreduction, independently of Flv1A, but only in the presence of Flv2 and Flv4. Strikingly, the lack of Flv3A resulted in strong downregulation of the heterocyst-specific uptake hydrogenase, which led to enhanced H2 photoproduction under both oxic and micro-oxic conditions. These results reveal a novel regulatory network between the Mehler-like reaction and the diazotrophic metabolism, which is of great interest for future biotechnological applications.


Asunto(s)
Anabaena , Dióxido de Carbono , Dióxido de Carbono/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Anabaena/genética , Anabaena/metabolismo , Oxígeno/metabolismo , Fotosíntesis/fisiología
4.
Acta Pharmacol Sin ; 44(1): 244-254, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35705687

RESUMEN

The combination of vascular endothelial growth factor (VEGF) inhibitors and tyrosine kinase inhibitors (TKIs) is newly available for molecular targeted therapy against non-small cell lung cancer (NSCLC) in clinic. However, the therapeutic benefits remain unsatisfying due to the poor drug delivery to targets of interest. In this study, we developed bevacizumab-coated gefitinib-loaded nanoparticles (BCGN) with dual-responsive drug release for inhibiting tumor angiogenesis and phosphorylation of epidermal growth factor receptor (EGFR). Through an exogenous corona strategy, bevacizumab is easily coated on gefitinib-loaded nanoparticles via electrostatic interaction. After intravenous injection, BCGN are efficiently accumulated in NSCLC tumors as confirmed by dual-model imaging. Bevacizumab is released from BCGN upon oxidation in tumor microenvironment, whereas gefitinib is released after being internalized by tumor cells and disassembled in reduction cytoplasm. The dual-responsive release of bevacizumab and gefitinib significantly inhibits tumor growth in both A549 and HCC827 human NSCLC models. Our approach provides a promising strategy to improve combinational molecular targeted therapy of NSCLC with precisely controlled drug release.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Gefitinib , Bevacizumab/uso terapéutico , Neoplasias Pulmonares/patología , Factor A de Crecimiento Endotelial Vascular , Terapia Molecular Dirigida , Quinazolinas/farmacología , Resistencia a Antineoplásicos , Línea Celular Tumoral , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Microambiente Tumoral
5.
J Environ Manage ; 340: 117969, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37084645

RESUMEN

The coexistence of nanoplastics and antibiotics in the aquatic environment has raised a complicated risk for ecosystems and human health. How the environmental factors e.g., light, regulate the interaction between nanoplastics and antibiotics and the resulting combined toxicity is poorly understood. Here, we investigated the individual and combined toxicity of polystyrene nanoplastics (nPS, 100 mg L1) and sulfamethoxazole (SMX, 2.5 and 10 mg L-1) toward the microalgae Chlamydomonas reinhardtii under low (LL, 16 µmol m-2·s-1), normal (NL, 40 µmol m-2·s-1), and high light (HL, 150 µmol m-2·s-1) in terms of cellular responses. Results indicated that the joint toxicity of nPS and SMX commonly exhibited a strong antagonistic/mitigative effect under LL/NL at 24 h, and under NL at 72 h. nPS could adsorb more SMX under LL/NL at 24 h (1.90/1.33 mg g-1) and under NL at 72 h (1.01 mg g-1), thereby alleviating SMX toxicity to C. reinhardtii. However, the self-toxicity of nPS had a negative influence on the degree of antagonism between nPS and SMX. The experimental results coupled with computational chemistry further revealed that the adsorption capacity of SMX on nPS was stimulated by low pH under LL/NL at 24 h (∼7.5), while by less co-existing saline ions (0.83 ppt) and algae-derived dissolved organic matter (9.04 mg L-1) under NL at 72 h. nPS toxicity that was responsible for the toxic action modes was mainly attributed to the shading effect induced by hetero-aggregation and hindrance of light transmittance (>60%), as well as being regulated by additives leaching (0.49-1.07 mg L-1) and oxidative stress. Overall, these findings provided a critical basis for the risk assessment and management of multiple pollutants in the complex natural environment.


Asunto(s)
Chlamydomonas reinhardtii , Microalgas , Nanopartículas , Contaminantes Químicos del Agua , Humanos , Poliestirenos/toxicidad , Microplásticos/toxicidad , Sulfametoxazol/toxicidad , Ecosistema , Contaminantes Químicos del Agua/análisis , Antibacterianos/farmacología
6.
Future Oncol ; 18(22): 2475-2482, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35703104

RESUMEN

Background: To survey the diversity of clinical target volumes (CTVs) for locally advanced supraglottic cancer (LA-SGC) with radical radiotherapy in mainland China. Methods: Radiation oncologists from 30 provinces and four representative cases (T2N1, T3N2b, T4N0, T4N2c) were included. Results: High risk (HR)-CTV included involved and the lower adjacent level was followed by most physicians (n = 160, 97.6%). In the N0-1 stage, whether contralateral levels II-III should be included in HR- or low risk (LR)-CTV was controversial. In the N2 stage, the bilateral levels II-IVb were included in LR-CTV (75-92.5% agreement). Levels Ib, V or VIb were included in CTV requiring certain conditions. Conclusion: Involved and lower adjacent levels were as HR-CTV. Whether bilateral levels II-IV are included in HR- or LR-CTV remain controversial.


Asunto(s)
Neoplasias , Radioterapia de Intensidad Modulada , Estudios Transversales , Humanos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Radioterapia de Intensidad Modulada/efectos adversos , Tomografía Computarizada por Rayos X
7.
Chembiochem ; 21(9): 1293-1297, 2020 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-31755629

RESUMEN

In 1994, the first DNAzyme named GR5 was reported, which specifically requires Pb2+ for its RNA cleavage activity. Three years later, the 8-17 DNAzyme was isolated. The 8-17 DNAzyme and the related 17E DNAzyme are also most active with Pb2+ , although other divalent metals can work as well. GR5 and 17E have the same substrate sequence, and their catalytic loops in the enzyme strands also have a few similar and conserved nucleotides. Considering these, we hypothesized that 17E might be a special form of GR5. To test this hypothesis, we performed systematic rational evolution experiments to gradually mutate GR5 toward 17E. By using the activity ratio in the presence of Pb2+ and Mg2+ for defining these two DNAzymes, the critical nucleotide was identified to be T12 in 17E for metal specificity. In addition, G9 in GR5 is a position not found in most 17E or 8-17 DNAzymes, and G9 needs to be added to rescue GR5 activity if T12 becomes a cytosine. This study highlights the links between these two classic and widely used DNAzymes, and offers new insight into the sequence-activity relationship related to metal selectivity.


Asunto(s)
ADN Catalítico/metabolismo , Plomo/química , Magnesio/química , ARN/metabolismo , Técnicas Biosensibles , Catálisis , ARN/genética
8.
Analyst ; 145(4): 1384-1388, 2020 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-31998880

RESUMEN

GR5 is the first reported DNAzyme, which has RNA cleavage activity in the presence of Pb2+. Due to its excellent selectivity, GR5 has been a popular DNAzyme for developing biosensors for Pb2+. The activity of DNAzymes is often affected by pH and salt, which may in turn affect the sensitivity of related sensors. Although pH can be readily controlled by using a buffer, the effect of salt is more complex. To have a systematic understanding, we herein measured the cleavage activity of GR5 in various concentrations of Na+ and Mg2+. Both metals inhibited the DNAzyme with Pb2+, and the inhibition constants were 1.8 mM Mg2+ and 33.4 mM Na+. For anions, F- inhibited GR5 more strongly than Br-, while Cl- was the least inhibiting anion, which was consistent with the solubility of their lead salts. The reaction can work similarly in many Good's buffers, while phosphate buffer should be avoided. Finally, GR5 is an optimal sequence based on the truncation and elongation studies. This study reveals important solution conditions that should be considered when designing and testing related biosensors for metal detection.


Asunto(s)
Técnicas Biosensibles/métodos , Colorimetría/métodos , ADN Catalítico/química , Plomo/análisis , Aniones , Secuencia de Bases , Tampones (Química) , Cationes , ADN Catalítico/metabolismo , Concentración de Iones de Hidrógeno , Magnesio/química , Concentración Osmolar , Sensibilidad y Especificidad , Alineación de Secuencia , Sodio/química
9.
Risk Anal ; 40(7): 1481-1506, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32426876

RESUMEN

The United States is funding homeland security programs with a large budget (e.g., 74.4 billion for FY 2019). A number of game-theoretic defender-attacker models have been developed to study the optimal defense resource allocation strategies for the government (defender) against the strategic adversary (attacker). However, to the best of our knowledge, the substitution or complementary effects between different types of defensive resources (e.g., human resource, land resource, and capital resource) have not been taken into consideration even though they exist in practice. The article fills this gap by studying a sequential game-theoretical resource allocation model and then exploring how the joint effectiveness of multiple security investments influences the defensive budget allocation among multiple potential targets. Three false belief models have been developed in which only the defender, only the attacker, and both the defender and attacker hold false beliefs about the joint effectiveness of resources. Regression analysis shows that there are significant substitution effects between human and capital resources. The results show that the defender will suffer a higher loss if he fails to consider the substitution or complementary effects. Interestingly, if the attacker holds a false belief while the defender does not, the defender will suffer an even higher loss, especially when the resources are substitutes. However, if both the attacker and defender hold false beliefs, there will be lower loss when resources are complementary. The results also show that the defender should allocate the highly effective resource when the resources substitute each other. This article provides some new insights to the homeland security resource allocation.

10.
Cell Physiol Biochem ; 45(5): 2021-2030, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29529605

RESUMEN

BACKGROUND/AIMS: Acetic acid (AcOH), a short-chain fatty acid, is reported to have some beneficial effects on metabolism. Therefore, the aim of this study was to investigate the regulatory mechanism of acetic acid on hepatic lipid metabolism in BRL-3A cells. METHODS: We cultured and treated BRL-3A cells with different concentrations of sodium acetate (neutralized acetic acid) and BML-275 (an AMPKα inhibitor). The total lipid droplet area was measured by oil red O staining, and the triglyceride content was determined by a triglyceride detection kit. We detected mRNA and protein levels of lipid metabolism-related signalling molecules by RT-PCR and Western blot. RESULTS: Acetic acid treatment increased AMPKα phosphorylation, which subsequently increased the expression and transcriptional activity of peroxisome proliferator-activated receptor α and upregulated the expression of lipid oxidation genes. These changes ultimate led to increasing levels of lipid oxidation in BRL-3A cells. Furthermore, elevated AMPKα phosphorylation reduced the expression and transcriptional activity of the sterol regulatory element-binding protein 1c, which reduced the expression of lipogenic genes, thereby decreasing lipid biosynthesis in BRL-3A cells. Consequently, triglyceride content in acetate-treated BRL-3A cells was significantly decreased. CONCLUSIONS: These results indicate that acetic acid activates the AMPKα signalling pathway, leading to increased lipid oxidation and decreased lipid synthesis in BRL-3A cells, thereby reducing liver fat accumulation in vitro.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Ácido Acético/toxicidad , Metabolismo de los Lípidos/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Acil-CoA Oxidasa/genética , Acil-CoA Oxidasa/metabolismo , Animales , Apoptosis/efectos de los fármacos , Carnitina O-Palmitoiltransferasa/genética , Carnitina O-Palmitoiltransferasa/metabolismo , Línea Celular , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , PPAR alfa/genética , PPAR alfa/metabolismo , Fosforilación/efectos de los fármacos , Pirazoles/farmacología , Pirimidinas/farmacología , Ratas , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/genética , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Triglicéridos/metabolismo
11.
Risk Anal ; 38(2): 215-225, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28799659

RESUMEN

The government, private sectors, and others users of the Internet are increasingly faced with the risk of cyber incidents. Damage to computer systems and theft of sensitive data caused by cyber attacks have the potential to result in lasting harm to entities under attack, or to society as a whole. The effects of cyber attacks are not always obvious, and detecting them is not a simple proposition. As the U.S. federal government believes that information sharing on cybersecurity issues among organizations is essential to safety, security, and resilience, the importance of trusted information exchange has been emphasized to support public and private decision making by encouraging the creation of the Information Sharing and Analysis Center (ISAC). Through a decision-theoretic approach, this article provides new perspectives on ISAC, and the advent of the new Information Sharing and Analysis Organizations (ISAOs), which are intended to provide similar benefits to organizations that cannot fit easily into the ISAC structure. To help understand the processes of information sharing against cyber threats, this article illustrates 15 representative information sharing structures between ISAC, government, and other participating entities, and provide discussions on the strategic interactions between different stakeholders. This article also identifies the costs of information sharing and information security borne by different parties in this public-private partnership both before and after cyber attacks, as well as the two main benefits. This article provides perspectives on the mechanism of information sharing and some detailed cost-benefit analysis.

12.
Drug Dev Ind Pharm ; 44(5): 808-816, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29216752

RESUMEN

Swellable microneedles (SMNs) are made of hydrogels and can deliver drug with controlled delivery rate by the cross-link density of the hydrogel. In this study, an acryl resin-based SMNs was developed for poorly water-soluble drugs. The making process of the SMNs is very simple and only need 60 min. The SMNs has high mechanical strength and is not easily broken. In-vitro release of SMNs-loaded model drug, granisetron base (GRB), was investigated. The results showed that seven days controlled release of GRB was obtained when SMNs contained pore-foaming agents (1.5% dicalcium phosphate (CaHPO4) and 1.5% polyvinylpyrrolidone (PVP)). The maximum amount delivered into skin was 86.158 ± 7.82% of the initial GRB (2.1 mg) loaded on SMNs preparation. Pharmacokinetics study in rats indicated a dose-dependent profile of plasma GRB concentrations and that the controlled release of 2.1 mg dose was observed for 144 hours. In conclusion, these SMNs provided a potential minimally invasive route for controlled-release systemic delivery of poorly water-soluble drugs.


Asunto(s)
Resinas Acrílicas/química , Granisetrón/administración & dosificación , Hidrogeles/química , Povidona/química , Animales , Preparaciones de Acción Retardada , Sistemas de Liberación de Medicamentos , Edema , Granisetrón/química , Ratas , Piel
13.
Sensors (Basel) ; 18(1)2017 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-29301236

RESUMEN

The solid Earth deforms elastically in response to variations of surface atmosphere, hydrology, and ice/glacier mass loads. Continuous geodetic observations by Global Positioning System (CGPS) stations and Gravity Recovery and Climate Experiment (GRACE) record such deformations to estimate seasonal and secular mass changes. In this paper, we present the seasonal variation of the surface mass changes and the crustal vertical deformation in the South China Block (SCB) identified by GPS and GRACE observations with records spanning from 1999 to 2016. We used 33 CGPS stations to construct a time series of coordinate changes, which are decomposed by empirical orthogonal functions (EOFs) in SCB. The average weighted root-mean-square (WRMS) reduction is 38% when we subtract GRACE-modeled vertical displacements from GPS time series. The first common mode shows clear seasonal changes, indicating seasonal surface mass re-distribution in and around the South China Block. The correlation between GRACE and GPS time series is analyzed which provides a reference for further improvement of the seasonal variation of CGPS time series. The results of the GRACE observations inversion are the surface deformations caused by the surface mass change load at a rate of about -0.4 to -0.8 mm/year, which is used to improve the long-term trend of non-tectonic loads of the GPS vertical velocity field to further explain the crustal tectonic movement in the SCB and surroundings.

14.
Bull Environ Contam Toxicol ; 99(6): 719-727, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29080111

RESUMEN

The ecotoxicity of α-Fe2O3 nanoparticles (NPs) and its interaction with a typical natural organic matter (NOM), fulvic acid (FA) on the physiological responses of Synechococcus sp. PCC7942 was studied. α-Fe2O3 NPs inhibited the algae growth at concentration higher than 10 mg L-1 and induced oxidative stress, indicated by enhanced antioxidant enzymes activities, elevated protein and sugar content. FA could efficiently recover cell growth and reduce antioxidant enzyme activities which induced by α-Fe2O3 NPs, indicating the toxicity of NPs was alleviated in the presence of FA. α-Fe2O3 NPs could form large aggregates coating on cell surface and inhibit cell growth. FTIR spectra verified FA interacted with α-Fe2O3 NPs through carboxyl groups, partly replaced the binding sites of α-Fe2O3 NPs on algal cell walls, thus reduced NPs aggregates coating on cell surface. This favors reducing the oxidative stress caused by direct contact and increasing light availability, thus mitigate NPs toxicity.


Asunto(s)
Benzopiranos/química , Compuestos Férricos/química , Nanopartículas/química , Synechococcus/fisiología , Antioxidantes , Estrés Oxidativo , Synechococcus/metabolismo
15.
Plant Cell Rep ; 35(1): 1-4, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26441055

RESUMEN

KEY MESSAGE: Photorespiration in Chlorella protothecoides plays an important role in photoprotection of photosystem (PS) II in the late phase of H(2) photoproduction, allowing PSII to supply more electrons to hydrogenase.


Asunto(s)
Chlorella/fisiología , Hidrógeno/metabolismo , Nitrógeno/deficiencia , Oxígeno/metabolismo , Chlorella/efectos de la radiación , Electrones , Hidrógeno/análisis , Hidrogenasas/metabolismo , Luz , Oxígeno/análisis , Complejo de Proteína del Fotosistema II/metabolismo , Proteínas de Plantas/metabolismo
16.
Planta ; 241(4): 1005-14, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25544543

RESUMEN

MAIN CONCLUSION: The AOX pathway in C. protothecoides plays an important role in the photoprotection of PSII by alleviating the inhibition of the repair of the photodamaged PSII during H2 photoproduction. We had demonstrated that nitrogen limitation (LN) substantially enhanced H2 photoproduction in Chlorella protothecoides. In the present study, the mitochondrial alternative oxidase (AOX) pathway capacity was found to increase significantly during H2 photoproduction under LN or under LN simultaneously with sulfur deprivation (LNS) conditions. The purpose of this study was to clarify the role of the AOX pathway during H2 photoproduction in C. protothecoides. The AOX pathway can affect H2 photoproduction in the following ways: (1) consuming O2, which is favorable for the establishment of anaerobiosis; (2) consuming NADPH and competing with hydrogenase for photosynthetic electrons, which would decrease the H2 photoproduction; (3) protecting photosystem (PS) II, which is a direct electron source for H2 photoproduction, from photoinhibition. In LN and LNS cultures, the inhibition of the AOX pathway reduced the H2 photoproduction significantly, and did not increase the amount of O2. But, the inhibition of the AOX pathway decreased the maximal photochemical efficiency of PSII (F v/F m) and the actual photochemical efficiency of PSII (Φ PSII) significantly, leading to photoinhibition, which would decrease the photosynthetic electrons transferred to hydrogenase. And, the inhibition of the AOX pathway did not change the level of photoinhibition in the presence of D1 protein synthesis inhibitor chloramphenicol, indicating that the inhibition of the AOX pathway did not accelerate the photodamage to PSII directly but inhibited the repair of the photodamaged PSII. Therefore, the mitochondrial AOX pathway in C. protothecoides plays an important role in the photoprotection of PSII by alleviating the inhibition of the repair of the photodamaged PSII during H2 photoproduction, which is thus able to supply more electrons to hydrogenase under LN and LNS conditions.


Asunto(s)
Chlorella/metabolismo , Hidrógeno/metabolismo , Mitocondrias/enzimología , Proteínas Mitocondriales/metabolismo , Oxidorreductasas/metabolismo , Proteínas de Plantas/metabolismo , Proteínas Algáceas/genética , Proteínas Algáceas/metabolismo , Chlorella/genética , Hidrogenasas/metabolismo , Luz , Proteínas Mitocondriales/genética , Oxidorreductasas/genética , Fotosíntesis , Complejo de Proteína del Fotosistema II/metabolismo , Hojas de la Planta/enzimología , Proteínas de Plantas/genética , Azufre/metabolismo
17.
J Ind Microbiol Biotechnol ; 42(4): 543-51, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25605047

RESUMEN

It has been found that recombinant Saccharomyces cerevisiae 6525 can produce high concentration of ethanol in one-step fermentation from the extract of Jerusalem artichoke tubers or inulin. However, the utilization rate of raw materials was low and the fermentation process was costly and complicated. Therefore, in this study, after the optimum processing conditions for ethanol production in fed-batch fermentation were determined in flask, the recombinant S. cerevisiae 6525 was first used to produce ethanol from the dry powder of Jerusalem artichoke tubers in 5-L agitating fermentor. After 72 h of fermentation, around 84.3 g/L ethanol was produced in the fermentation liquids, and the conversion efficiency of inulin-type sugars to ethanol was 0.453, or 88.6 % of the theoretical value of 0.511. This study showed high feasibility of bioethanol industrial production from the Jerusalem artichoke tubers and provided a basis for it in the future.


Asunto(s)
Etanol/metabolismo , Fermentación , Helianthus/metabolismo , Tubérculos de la Planta/metabolismo , Saccharomyces cerevisiae/metabolismo , Técnicas de Cultivo Celular por Lotes , Reactores Biológicos , Etanol/provisión & distribución , Estudios de Factibilidad , Helianthus/química , Inulina/metabolismo , Tubérculos de la Planta/química , Saccharomyces cerevisiae/genética , Factores de Tiempo
18.
J Hazard Mater ; 476: 135062, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-38959831

RESUMEN

Microplastics (MPs) are emerging pollutants, causing potential threats to aquatic ecosystems and serious concern in aggregating with microalgae (critical primary producers). When entering water bodies, MPs are expected to sink below the water surface and disperse into varying water compartments with different light intensities. However, how light influences the aggregation processes of algal cells onto MPs and the associated molecular coupling mechanisms and derivative risks remain poorly understood. Herein, we investigated the aggregation behavior between polystyrene microplastics (mPS, 10 µm) and Chlorella pyrenoidosa under low (LL, 15 µmol·m-2·s-1), normal (NL, 55 µmol·m-2·s-1), and high light (HL, 150 µmol·m-2·s-1) conditions from integrated in vivo and in silico assays. The results indicated that under LL, the mPS particles primarily existed independently, whereas under NL and HL, C. pyrenoidosa tightly bounded to mPS by secreting more protein-rich extracellular polymeric substances. Infrared spectroscopy analysis and density functional theory calculation revealed that the aggregation formation was driven by non-covalent interaction involving van der Waals force and hydrogen bond. These processes subsequently enhanced the deposition and adherence capacity of mPS and relieved its phytotoxicity. Overall, our findings advance the practical and theoretical understanding of the ecological impacts of MPs in complex aquatic environments.


Asunto(s)
Chlorella , Microalgas , Microplásticos , Poliestirenos , Contaminantes Químicos del Agua , Microplásticos/toxicidad , Microplásticos/química , Poliestirenos/química , Poliestirenos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/efectos de la radiación , Microalgas/efectos de los fármacos , Microalgas/efectos de la radiación , Chlorella/metabolismo , Chlorella/efectos de la radiación , Chlorella/efectos de los fármacos , Medición de Riesgo , Luz
19.
Pathogens ; 13(8)2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39204292

RESUMEN

Engineered circular RNAs (circRNAs) are a class of single-stranded RNAs with head-to-tail covalently linked structures that integrate open reading frames (ORFs) and internal ribosome entry sites (IRESs) with the function of coding and expressing proteins. Compared to mRNA vaccines, circRNA vaccines offer a more improved method that is safe, stable, and simple to manufacture. With the rapid revelation of the biological functions of circRNA and the success of Severe Acute Respiratory Coronavirus Type II (SARS-CoV-2) mRNA vaccines, biopharmaceutical companies and researchers around the globe are attempting to develop more stable circRNA vaccines for illness prevention and treatment. Nevertheless, research on circRNA vaccines is still in its infancy, and more work and assessment are needed for their synthesis, delivery, and use. In this review, based on the current understanding of the molecular biological properties and immunotherapeutic mechanisms of circRNA, we summarize the current preparation methods of circRNA vaccines, including design, synthesis, purification, and identification. We discuss their delivery strategies and summarize the challenges facing the clinical application of circRNAs to provide references for circRNA vaccine-related research.

20.
Mar Environ Res ; 196: 106414, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38394975

RESUMEN

Estuaries, acting as transitional habitats receiving species introductions from both freshwater and marine sources, undergo significant impacts from global climate changes. Planktonic microorganisms contribute significantly to estuarine biodiversity and ecological stability. These microorganisms primarily fall into three groups: eukaryotic plankton, particle-associated bacteria, and free-living bacteria. Understanding the structural characteristics and interactions within these subcommunities is crucial for comprehending estuarine dynamics. We collected samples from three distinct locations (< 0.1 PSU, 6.6 PSU, and 19 PSU) within the Yangtze River estuary. Samples underwent analysis for physicochemical indicators, while microbial communities were subjected to 16S/18S rRNA amplicon sequencing. Additionally, simulated mixing experiments were conducted using samples of varying salinities. Estuary samples, combined with simulated experiments, were employed to collectively examine the structural characteristics and assembly processes of estuarine microbes. Our research highlights the considerable impact of phylogenetic classification on prokaryotic behavior in these communities. We observed a transition in assembly processes from primarily stochastic for particle-associated bacteria to a predominant influence of homogeneous selection as salinity increased. Particle-associated bacterial communities exhibited a greater influence of stochastic processes compared to free-living bacteria, showcasing higher stability in diversity. The variations in composition and structure of estuarine microbial subcommunities were influenced by diverse environmental factors. Particle-associated bacteria displayed elevated network characterization values and established closer interactions with eukaryotic plankton. Structural equation modeling (SEM) analysis revealed that free-living bacteria displayed a heightened sensitivity to environmental factors and exerted a more significant influence on assembly processes and network characteristics. Simulated mixing in these environments resulted in the loss of species with similar microbial taxonomic relationships. The functioning of bacterioplankton is influenced by salinity and the processes governing their assembly, particularly in relation to different living states. These findings significantly contribute to our understanding of the intricate interplay between prokaryotic and eukaryotic plankton microorganisms in highly dynamic environments, laying a robust foundation for further exploration into the ecological mechanisms governing microbial dynamics in estuaries.


Asunto(s)
Microbiota , Plancton , Ríos , Estuarios , Filogenia , Organismos Acuáticos , Bacterias/genética , Ecosistema
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