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1.
Nat Commun ; 15(1): 3854, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719830

RESUMO

Phasing down fossil fuels is crucial for climate mitigation. Even though 80-90% of fossil fuels are used to provide energy, their use as feedstock to produce plastics, fertilizers, and chemicals, is associated with substantial CO2 emissions. However, our understanding of hard-to-abate chemical production remains limited. Here we developed a chemical process-based material flow model to investigate the non-energy use of fossil fuels and CO2 emissions in China. Results show in 2017, the chemical industry used 0.18 Gt of coal, 88.8 Mt of crude oil, and 12.9 Mt of natural gas as feedstock, constituting 5%, 15%, and 7% of China's respective total use. Coal-fed production of methanol, ammonia, and PVCs contributes to 0.27 Gt CO2 emissions ( ~ 3% of China's emissions). As China seeks to balance high CO2 emissions of coal-fed production with import dependence on oil and gas, improving energy efficiency and coupling green hydrogen emerges as attractive alternatives for decarbonization.

2.
Microorganisms ; 12(3)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38543490

RESUMO

Bacillus subtilis, a probiotic bacterium with engineering potential, is widely used for the expression of exogenous proteins. In this study, we utilized the integrative plasmid pDG364 to integrate the hemagglutinin-neuraminidase (HN) gene from Newcastle disease virus (NDV) into the genome of the B. subtilis 168 model strain. We successfully constructed a recombinant B. subtilis strain (designated B. subtilis RH) that displays a truncated HN antigen fragment on the surface of its spores and further evaluated its immunogenic effects in mice. Using ELISA, we quantified the levels of IgG in serum and secretory IgA (sIgA) in intestinal contents. The results revealed that the recombinant B. subtilis RH elicited robust specific mucosal and humoral immune responses in mice. Furthermore, B. subtilis RH demonstrated potential mucosal immune adjuvant properties by fostering the development of immune organs and augmenting the number of lymphocytes in the small intestinal villi. Additionally, the strain significantly upregulated the relative expression of inflammatory cytokines such as IL-1ß, IL-6, IL-10, TNF-α, and IFN-γ in the small intestinal mucosa. In conclusion, the B. subtilis RH strain developed in this study exhibits promising mucosal immunogenic effects. It holds potential as a candidate for an anti-NDV mucosal subunit vaccine and offers a novel preventive strategy for the poultry industry against this disease.

3.
FASEB J ; 38(5): e23530, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38466314

RESUMO

Brevibacillus laterosporus is a strain of probiotic bacteria that has been widely used in pest control, cash crop, and other production areas. However, few studies have been conducted on its use as a feed additive in animals. Therefore, the probiotic potential of B. laterosporus PBC01 was evaluated by characterizing hydrophobicity, auto-aggregation activity, bile salt and simulated gastrointestinal fluid tolerance, bienzymatic, and antibacterial activity. Antibiotic susceptibility, hemolysis assays, and supplemental feeding of mice were also performed to evaluate safety features. Our results showed that B. laterosporus PBC01 had moderate hydrophobicity, high auto-agglutination ability. Meanwhile, B. laterosporus PBC01 had good tolerance to bile salt and simulated gastrointestinal fluid. It had the ability to secrete protease, cellulase, and to inhibit various pathogens. In addition, B. laterosporus PBC01 was sensitive to many antibiotics, and did not produce hemolysin. In the safety assessment of mice, it did not cause any deaths, nor did it affect the cell components of blood, antioxidant capacity, and reproductive health. The study indicated the great probiotic characteristics and safety of B. laterosporus PBC01. This may provide a theoretical basis for the clinical application and development of probiotic-based feed additives.


Assuntos
Bacillus , Brevibacillus , Animais , Camundongos , Antibacterianos/farmacologia , Ácidos e Sais Biliares
4.
ACS Nano ; 17(5): 5033-5046, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36867454

RESUMO

Effective drug delivery in the central nervous system (CNS) needs to have long blood-circulation half-lives, to pass through the blood-brain barrier (BBB), and subsequently to be taken up by target cells. Herein, a traceable CNS delivery nanoformulation (RVG-NV-NPs) is developed by encapsulating bexarotene (Bex) and AgAuSe quantum dots (QDs) within Lamp2b-RVG-overexpressed neural stem cell (NSC) membranes. The high-fidelity near-infrared-II imaging by AgAuSe QDs offers a possibility of in vivo monitoring the multiscale delivery process of the nanoformulation from the whole-body to the single-cell scale. It was revealed the synergy of acetylcholine receptor-targeting of RVG and the natural brain-homing and low immunogenicity of NSC membranes prolong the blood circulation, facilitate BBB crossing and nerve cell targeting of RVG-NV-NPs. Thus, in Alzheimer's disease (AD) mice, the intravenous delivery of as low as 0.5% of oral dose Bex showed highly effective up-regulation of the apolipoprotein E expression, resulting rapid alleviation of ∼40% ß-amyloid (Aß) level in the brain interstitial fluid after a single dose administration. The pathological progression of Aß in AD mice is completely suppressed during a 1 month treatment, thus effectively protecting neurons from Aß-induced apoptosis and maintaining the cognitive abilities of AD mice.


Assuntos
Doença de Alzheimer , Camundongos , Animais , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/tratamento farmacológico , Encéfalo/metabolismo , Barreira Hematoencefálica/metabolismo , Peptídeos beta-Amiloides/metabolismo , Membrana Celular/metabolismo
5.
Biotechnol J ; 17(10): e2200006, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35765726

RESUMO

Axonal transport plays a significant role in the establishment of neuronal polarity, axon growth, and synapse formation during neuronal development. The axon of a naturally growing neuron is a highly complex and multifurcated structure with a large number of bends and branches. Nowadays, the study of dynamic axonal transport in morphologically complex neurons is greatly limited by the technological barrier. Here, a sparse gene transfection strategy was developed to locate fluorescent mCherry in the lysosome of primary neurons, thus enabling us to track the lysosome-based axonal transport with a single-particle resolution. Thereby, several axonal transport models were observed, including the forward or backward transport model, stop-and-go model, repeated back-and-forth transport model, and cross-branch transport model. Then, the accurate single-particle velocity quantification by TrackMate revealed a highly heterogeneous and discontinuous transportation process of lysosome-based axonal transport in freely orientated axons. And, multiple physical factors, such as the axonal structure and the size of particles, were disclosed to affect the velocity of particle transporting in freely orientated axons. The combined single-particle fluorescence tracking and TrackMate assay can be served as a facile tool for evaluating axonal transport in neuronal development and axonal transport-related diseases.


Assuntos
Transporte Axonal , Axônios , Transporte Axonal/fisiologia , Axônios/metabolismo , Fluorescência , Lisossomos , Neurônios
6.
Biomed Mater ; 17(2)2022 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-35073527

RESUMO

Controllable regulation of stem cell differentiation is a critical concern in stem cell-based regenerative medicine. In particular, there are still great challenges in controlling the directional differentiation of neural stem cells (NSCs) into neurons. Herein, we developed a novel linear-branched poly(ß-amino esters) (S4-TMPTA-BDA-DT, STBD) through a two-step reaction. The synthesized linear-branched polymers possess multiple positively charged amine terminus and degradable intermolecular ester bonds, thus endowing them with excellent properties such as high gene load, efficient gene delivery, and effective gene release and transcription in cells. In the mCherry transfection test, a high transfection efficiency of approximately 70% was achieved in primary NSCs after a single transfection. Moreover, STBD also showed high biocompatibility to NSCs without disturbing their viability and neural differentiation. With the high gene delivery property, STBD is capable of delivering siRNA (shSOX9) expression plasmid into NSCs to significantly interfere with the expression of SOX9, thus enhancing the neuronal differentiation and maturation of NSCs. The STBD/DNA nano-polyplex represents a powerful non-viral approach of gene delivery for manipulating the differentiation of stem cells, showing broad application prospects in NSC-based regenerative therapy for treating neurodegenerative diseases.


Assuntos
Ésteres , Células-Tronco Neurais , Diferenciação Celular/genética , DNA/química , Transfecção
7.
Adv Mater ; 33(13): e2006357, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33624894

RESUMO

Alzheimer's disease (AD) is a common dementia that is currently incurable. The existing treatments can only moderately relieve the symptoms of AD to slow down its progress. How to achieve effective neural regeneration to ameliorate cognitive impairments is a major challenge for current AD treatment. Here, the therapeutic potential of a nanoformulation-mediated neural stem cell (NSC) therapy capable of simultaneous Aß clearance and neural regeneration is investigated in a murine model. Genetically engineered NSCs capable of stably and continuously expressing neprilysin (NEP) are developed to enhance Aß degradation and NSC survival in the brain. A PBAE-PLGA-Ag2 S-RA-siSOX9 (PPAR-siSOX9) nanoformulation with high gene/drug deliverability is synthesized to overcome AD microenvironment-associated adverse effects and to promote neuronal differentiation of the NEP-expressing NSCs. For achieving accurate stereotactic transplantation, Ag2 S quantum-dot-based fluorescence imaging is used to guide NSC transplantation in real time. This strategy shows numerous benefits, including efficient and long-lasting Aß degradation, improved neural regeneration, and accurate cell transplantation. It is shown that a single administration of this therapy achieves long-term efficacy (6 months) with respect to memory reversal and improvement of learning deficits.


Assuntos
Doença de Alzheimer/terapia , Precursor de Proteína beta-Amiloide/metabolismo , Nanomedicina/métodos , Regeneração Nervosa , Transplante de Células-Tronco , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Animais , Composição de Medicamentos , Camundongos , Presenilina-1/metabolismo
8.
Adv Sci (Weinh) ; 7(8): 1903783, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32328436

RESUMO

Light-based technique, including optical imaging and photoregulation, has become one of the most important tools for both fundamental research and clinical practice, such as cell signal sensing, cancer diagnosis, tissue engineering, drug delivery, visual regulation, neuromodulation, and disease treatment. In particular, low energy near-infrared (NIR, 700-1700 nm) light possesses lower phototoxicity and higher tissue penetration depth in living systems as compared with ultraviolet/visible light, making it a promising tool for in vivo applications. Currently, the NIR light-based imaging and photoregulation strategies have offered a possibility to real-time sense and/or modulate specific cellular events in deep tissues with subcellular accuracy. Herein, the recent progress with respect to NIR light for monitoring and modulating the spatiotemporal dynamics of cell functions in living systems are summarized. In particular, the applications of NIR light-based techniques in cancer theranostics, regenerative medicine, and neuroscience research are systematically introduced and discussed. In addition, the challenges and prospects for NIR light-based cell sensing and regulating techniques are comprehensively discussed.

9.
J Nat Prod ; 79(8): 2022-31, 2016 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-27441892

RESUMO

Six new dibenzo-α-pyrones, rhizopycnolides A (1) and B (2) and rhizopycnins A-D (3-6), together with eight known congeners (7-14), were isolated from the endophytic fungus Rhizopycnis vagum Nitaf22 obtained from Nicotiana tabacum. The structures of the new compounds were unambiguously elucidated using NMR, HRESIMS, TDDFT ECD calculation, and X-ray crystallography data. Rhizopycnolides A (1) and B (2) feature an uncommon γ-butyrolactone-fused dibenzo-α-pyrone tetracyclic skeleton (6/6/6/5), while rhizopycnin B (4) was the first amino group containing dibenzo-α-pyrone. Rhizopycnolides A (1) and B (2) are proposed to be biosynthesized from polyketide and tricarboxylic acid cycle pathways. The isolated compounds were tested for their antibacterial, antifungal, and cytotoxic activities. Among them, rhizopycnolide A (1), rhizopycnins C (5) and D (6), TMC-264 (8), penicilliumolide D (11), and alternariol (12) were active against the tested pathogenic bacteria Agrobacterium tumefaciens, Bacillus subtilis, Pseudomonas lachrymans, Ralstonia solanacearum, Staphylococcus hemolyticus, and Xanthomonas vesicatoria with MIC values in the range 25-100 µg/mL. Rhizopycnin D (6) and TMC-264 (8) strongly inhibited the spore germination of Magnaporthe oryzae with IC50 values of 9.9 and 12.0 µg/mL, respectively. TMC-264 (8) showed potent cytotoxicity against five human cancer cell lines (HCT-116, HepG2, BGC-823, NCI-H1650, and A2780) with IC50 values of 3.2-7.8 µM.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Ascomicetos/química , Cromonas/isolamento & purificação , Cromonas/farmacologia , Policetídeos/isolamento & purificação , Policetídeos/farmacologia , 4-Butirolactona/química , Agrobacterium tumefaciens/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antifúngicos/química , Antifúngicos/isolamento & purificação , Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/metabolismo , Cromonas/química , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Células HCT116 , Células Hep G2 , Compostos Heterocíclicos com 3 Anéis/química , Compostos Heterocíclicos com 3 Anéis/farmacologia , Humanos , Lactonas/farmacologia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Policetídeos/química , Pseudomonas/efeitos dos fármacos , Ralstonia solanacearum/efeitos dos fármacos , Staphylococcus/efeitos dos fármacos , Nicotiana/microbiologia , Xanthomonas vesicatoria/efeitos dos fármacos
10.
Molecules ; 19(9): 14221-34, 2014 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-25211003

RESUMO

Hyalodendriella sp. Ponipodef12, an endophytic fungus from the hybrid "Neva" of Populus deltoides × P. nigra, is a high producer of the bioactive dibenzo-α-pyrones botrallin and TMC-264. However, both the botrallin and TMC-264 produced by Hyalodendriella sp. Ponipodef12 were retained as both intracellular and extracellular products. The aim of this study was to evaluate an in situ macroporous resin adsorption for enhancement of botrallin and TMC-264 production in mycelial liquid culture of Hyalodendriella sp. Ponipodef12. Production of botrallin and TMC-264 was most effectively enhanced by macroporous resin DM-301 among the thirteen nonionic macroporous resins tested. The highest botrallin yield (51.47 mg/L, which was 2.29-fold higher than the control at 22.49 mg/L) was obtained by adding resin DM-301 at 4.38% (g/mL) to the culture broth on day 24 and allowing a period of 4 days for adsorption. The highest TMC-264 yield reached 47.74 mg/L, which was 11.76-fold higher than that of the control (4.06 mg/L), and was achieved by adding DM-301 resin at 4.38% (w/v) in the culture broth on day 24 and allowing a period of 6 days for adsorption. The results show that in situ resin adsorption is an effective strategy for enhancing production of botrallin and TMC-264, and also for facilitating their recovery from mycelial liquid culture of Hyalodendriella sp. Ponipodef12.


Assuntos
Compostos Heterocíclicos com 3 Anéis/isolamento & purificação , Pironas/isolamento & purificação , Adsorção , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/metabolismo , Reatores Biológicos , Técnicas de Cultura , Compostos Heterocíclicos com 3 Anéis/metabolismo , Micélio/crescimento & desenvolvimento , Micélio/metabolismo , Porosidade , Pironas/metabolismo , Resinas Sintéticas/química
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