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1.
Adv Mater ; 36(25): e2402532, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38563503

RESUMO

Due to inherent differences in cellular composition and metabolic behavior with host cells, tumor-harbored bacteria can discriminatorily affect tumor immune landscape. However, the mechanisms by which intracellular bacteria affect antigen presentation process between tumor cells and antigen-presenting cells (APCs) are largely unknown. The invasion behavior of attenuated Salmonella VNP20009 (VNP) into tumor cells is investigated and an attempt is made to modulate this behavior by modifying positively charged polymers on the surface of VNP. It is found that non-toxic chitosan oligosaccharide (COS) modified VNP (VNP@COS) bolsters the formation of gap junction between tumor cells and APCs by enhancing the ability of VNP to infect tumor cells. On this basis, a bacterial biohybrid is designed to promote in situ antigen cross-presentation through intracellular bacteria induced gap junction. This bacterial biohybrid also enhances the expression of major histocompatibility complex class I molecules on the surface of tumor cells through the incorporation of Mdivi-1 coupled with VNP@COS. This strategic integration serves to heighten the immunogenic exposure of tumor antigens; while, preserving the cytotoxic potency of T cells. A strategy is proposed to precisely controlling the function and local effects of microorganisms within tumors.


Assuntos
Apresentação de Antígeno , Quitosana , Junções Comunicantes , Salmonella , Humanos , Quitosana/química , Linhagem Celular Tumoral , Junções Comunicantes/metabolismo , Salmonella/imunologia , Animais , Apresentação Cruzada , Camundongos , Oligossacarídeos/química , Neoplasias/imunologia , Neoplasias/patologia , Células Apresentadoras de Antígenos/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Antígenos de Histocompatibilidade Classe I/imunologia
2.
Nano Lett ; 24(15): 4602-4609, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38567988

RESUMO

Oxygen vacancy (OV) engineering has been widely applied in different types of metal oxide-based photocatalytic reactions. Our study has shown that the redistributed OVs resulting from voids in CeO2 rods lead to significant differences in the band structure in space. The flat energy band within the highly crystallized bulk region hinders the recombination of photogenerated carrier pairs during the transfer process. The downward curved energy band in the surface region enhances the activation of the absorbents. Therefore, the localization of the band structure through crystal structure regionalization renders V-CeO2 capable of achieving efficient utilization of photogenerated carriers. Practically, the V-CeO2 rod shows a remarkable turnover number of 190.58 µmol g-1 h-1 in CO2 photoreduction, which is ∼9.4 times higher than that of D-CeO2 (20.46 µmol g-1 h-1). The designed modularization structure in our work is expected to provide important inspiration and guidance in coordinating the kinetic behavior of carriers in OV defect-rich photocatalysts.

3.
Nano Lett ; 24(1): 130-139, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38150297

RESUMO

Photothermal immunotherapy has become a promising strategy for tumor treatment. However, the intrinsic drawbacks like light instability, poor immunoadjuvant effect, and poor accumulation of conventional inorganic or organic photothermal agents limit their further applications. Based on the superior carrying capacity and active tumor targeting property of living bacteria, an immunoadjuvant-intensified and engineered tumor-targeting bacterium was constructed to achieve effective photothermal immunotherapy. Specifically, immunoadjuvant imiquimod (R837)-loaded thermosensitive liposomes (R837@TSL) were covalently decorated onto Rhodobacter sphaeroides (R.S) to obtain nanoimmunoadjuvant-armed bacteria (R.S-R837@TSL). The intrinsic photothermal property of R.S combined R837@TSL to achieve in situ near-infrared (NIR) laser-controlled release of R837. Meanwhile, tumor immunogenic cell death (ICD) caused by photothermal effect of R.S-R837@TSL, synergizes with released immunoadjuvants to promote maturation of dendritic cells (DCs), which enhance cytotoxic T lymphocytes (CTLs) infiltration for further tumor eradication. The photosynthetic bacteria armed with immunoadjuvant-loaded liposomes provide a strategy for immunoadjuvant-enhanced cancer photothermal immunotherapy.


Assuntos
Nanopartículas , Neoplasias , Rhodobacter sphaeroides , Humanos , Adjuvantes Imunológicos , Lipossomos , Imiquimode , Neoplasias/patologia , Imunoterapia , Linhagem Celular Tumoral , Fototerapia
4.
J Control Release ; 359: 347-358, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37277054

RESUMO

Temozolomide (TMZ) is an oral DNA-alkylating drug used in colorectal cancer (CRC) chemotherapy. In this work, we proposed a safe and biomimetic platform for macrophages-targeted delivery of TMZ and O6-benzylguanine (O6-BG). TMZ was loaded in poly (D, l-lactide-coglycolide) (PLGA) nanoparticles, followed by sequential coating with O6-BG-grafted chitosan (BG-CS) layers and yeast shell walls (YSW) via layer-by-layer assembly (LBL) process, forming TMZ@P-BG/YSW biohybrids. Due to the yeast cell membrane-camouflage, TMZ@P-BG/YSW particles exhibited significantly enhanced colloidal stability as well as low premature drug leakage in simulated gastrointestinal conditions. In vitro drug release profiles of TMZ@P-BG/YSW particles revealed noticeable higher TMZ release in simulated tumor acidic environment within 72 h. Meanwhile, O6-BG could down-regulate MGMT expression in CT26 colon carcinoma cells, ultimately facilitating TMZ-induced tumor cell death. After oral delivery of yeast cell membrane-camouflaged particles containing fluorescent tracer (Cy5), TMZ@P-BG/YSW and bare YSW displayed high retention time of 12 h in the colon and small intestine (ileum). Correspondingly, oral gavage administration of TMZ@P-BG/YSW particles afforded favorable tumor-specific retention and superior tumor growth inhibition. Overall, TMZ@P-BG/YSW is validated to be a safe, targetable and effective formulation, paving a new avenue towards highly effective and precise treatment of malignancies.


Assuntos
Nanopartículas , Neoplasias , Dacarbazina/farmacologia , Saccharomyces cerevisiae , O(6)-Metilguanina-DNA Metiltransferase , Temozolomida , Membrana Celular/metabolismo , Antineoplásicos Alquilantes/farmacologia , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico
5.
Adv Mater ; 35(38): e2302551, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37310059

RESUMO

Local lung microbiota is closely associated with lung tumorigenesis and therapeutic response. It is found that lung commensal microbes induce chemoresistance in lung cancer by directly inactivating therapeutic drugs via biotransformation. Accordingly, an inhalable microbial capsular polysaccharide (CP)-camouflaged gallium-polyphenol metal-organic network (MON) is designed to eliminate lung microbiota and thereby abrogate microbe-induced chemoresistance. As a substitute for iron uptake, Ga3+ released from MON acts as a "Trojan horse" to disrupt bacterial iron respiration, effectively inactivating multiple microbes. Moreover, CP cloaks endow MON with reduced immune clearance by masquerading as normal host-tissue molecules, significantly increasing residence time in lung tissue for enhanced antimicrobial efficacy. In multiple lung cancer mice models, microbe-induced drug degradation is remarkably inhibited when drugs are delivered by antimicrobial MON. Tumor growth is sufficiently suppressed and mouse survival is prolonged. The work develops a novel microbiota-depleted nanostrategy to overcome chemoresistance in lung cancer by inhibiting local microbial inactivation of therapeutic drugs.


Assuntos
Anti-Infecciosos , Gálio , Neoplasias Pulmonares , Microbiota , Nanopartículas , Animais , Camundongos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Polifenóis , Pulmão/metabolismo , Ferro , Neoplasias Pulmonares/tratamento farmacológico , Polissacarídeos
6.
Nano Lett ; 23(12): 5595-5602, 2023 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-37327393

RESUMO

Chronic inflammation and hypoxia in the microenvironment of diabetic foot ulcers (DFUs) can result in sustained vascular impairment, hindering tissue regeneration. While both nitric oxide and oxygen have been shown to promote wound healing in DFUs through anti-inflammatory and neovascularization, there is currently no available therapy that delivers both. We present a novel hydrogel consisting of Weissella and Chlorella, which alternates between nitric oxide and oxygen production to reduce chronic inflammation and hypoxia. Further experiments indicate that the hydrogel accelerates wound closure, re-epithelialization, and angiogenesis in diabetic mice and improves the survival of skin grafts. This dual-gas therapy holds promise as a potential treatment option for the management of diabetic wounds.


Assuntos
Chlorella , Diabetes Mellitus Experimental , Pé Diabético , Animais , Camundongos , Óxido Nítrico/uso terapêutico , Oxigênio , Diabetes Mellitus Experimental/terapia , Cicatrização , Hidrogéis/uso terapêutico , Pé Diabético/terapia , Hipóxia , Inflamação
7.
Nano Lett ; 23(10): 4375-4383, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-37159332

RESUMO

Microorganism-mediated self-assembling of living formulations holds great promise for disease therapy. Here, we constructed a prebiotic-probiotic living capsule (PPLC) by coculturing probiotics (EcN) with Gluconacetobacter xylinus (G. xylinus) in a prebiotic-containing fermentation broth. Through shaking the culture, G. xylinus secretes cellulose fibrils that can spontaneously encapsulate EcN to form microcapsules under shear forces. Additionally, the prebiotic present in the fermentation broth is incorporated into the bacterial cellulose network through van der Waals forces and hydrogen bonding. Afterward, the microcapsules were transferred to a selective LB medium, which facilitated the colonization of dense probiotic colonies within them. The in vivo study demonstrated that PPLC-containing dense colonies of EcN can antagonize intestinal pathogens and restore microbiota homeostasis by showing excellent therapeutic performance in treating enteritis mice. The in situ self-assembly of probiotics and prebiotics-based living materials provides a promising platform for the treatment of inflammatory bowel disease.


Assuntos
Doenças Inflamatórias Intestinais , Prebióticos , Animais , Camundongos , Cápsulas , Técnicas de Cocultura , Celulose
8.
Biomaterials ; 296: 122072, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36878091

RESUMO

Alcohol intoxication causes serious diseases, whereas current treatments are mostly supportive and unable to convert alcohol into nontoxic products in the digestive tract. To address this issue, an oral intestinal-coating coacervate antidote containing acetic acid bacteria (AAB) and sodium alginate (SA) mixture was constructed. After oral administration, SA reduces absorption of ethanol and promotes the proliferation of AAB, and AAB converts ethanol to acetic acid or carbon dioxide and water by two sequential catalytic reactions in the presence of membrane-bound alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH). In vivo study shows that the bacteria-based coacervate antidote can significantly reduce the blood alcohol concentration (BAC) and effectively alleviates alcoholic liver injury in mice. Given the convenience and effectiveness of oral administration, AAB/SA can be used as a promising candidate antidote for relieving alcohol-induced acute liver injury.


Assuntos
Intoxicação Alcoólica , Antídotos , Camundongos , Animais , Antídotos/farmacologia , Antídotos/uso terapêutico , Concentração Alcoólica no Sangue , Etanol/farmacologia , Fígado , Aldeído Desidrogenase/farmacologia
9.
Nanoscale Horiz ; 8(4): 489-498, 2023 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-36786021

RESUMO

Combinations of multiple enzymes for cascade catalysis have been widely applied in biomedicine, but the integration of a natural bioenzyme with an inorganic nanozyme is less developed. Inspired by the abundant content of superoxide dismutase (SOD) in Spirulina platensis (SP), we establish an integrated cascade catalysis for anti-inflammation therapy by decorating catalase (CAT)-biomimetic ceria nanoparticles (CeO2) onto the SP surface via electrostatic interaction to build microalgae-based biohybrids. The biohybrids exhibit combined catalytical competence for preferentially transforming superoxide anion radicals (O2˙-) to hydrogen peroxide (H2O2), and subsequently catalyzing H2O2 disproportionation to water and oxygen. In ulcerative colitis and Crohn's disease, the biohybrids reveal a satisfactory therapeutic effect owing to the synergistic reactive oxygen species (ROS)-scavenging capacity, suggesting a new train of thought for enzyme-based biomedical application.


Assuntos
Microalgas , Peróxido de Hidrogênio , Superóxidos , Superóxido Dismutase , Anti-Inflamatórios/uso terapêutico , Catálise
10.
Environ Res ; 223: 115441, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36758917

RESUMO

Two-dimensional La2Ti2O7 nanosheets with regular morphology and good dispersion were prepared by the hydrothermal method under a magnetic field. Zero-dimensional Pt quantum dots (Pt-QDs) were loaded on the La2Ti2O7 nanosheets. The electron-hole separation and carrier transfer in the Pt-loaded La2Ti2O7 nanosheets were significantly enhanced. The La2Ti2O7 nanosheets loaded with 3 wt% Pt-QDs exhibit the largest NO removal efficiency of 51% and less than 3.2 ppb NO2 intermediate pollutant in 30 min. The high photocatalytic ability was attributed to the surface plasmon resonance in Pt-QDs and the enhanced electron-hole separation. A large number of e-, h+, •OH and •O2- active species were formed on the surface of Pt-loaded La2Ti2O7 nanosheets under light irradiation. The conversion pathway from NO to NO3- was verified by the in situ diffuse reflectance infrared Fourier-transform spectroscopy and DFT calculation. This work supplies a feasible approach to responsive photocatalysts for efficient, stable, and selective NO removal avoiding the NO2 secondary pollutant.


Assuntos
Pontos Quânticos , Pontos Quânticos/química , Luz , Dióxido de Nitrogênio , Titânio
11.
J Control Release ; 356: 59-71, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36842488

RESUMO

The endogenous H2S plays an important role in the occurrence and development of colon cancer, and is related to the abnormal blood vessels. Here, we reported on a sulfhydryl hyaluronid-based hydrogel (HA-SH) synthesized by amide reaction and further obtained a bacterial hydrogel by loading Thiobacillus denitrificans to the hydrogel for targeting adhesion to the colon. It was found that the loaded bacteria in HA-SH hydrogel can scavenge excess H2S in colon cancer, then promote tumor vascular normalization and improve the delivery of chemotherapy drug CPT to inhibit tumor progression. Both in vivo and in vitro experiments show that the self-crosslinked bacterial hydrogel has satisfactory effects in inhibiting tumor progression and promoting tumor vascular normalization in colon cancer. This study presents an efficient method to target the colon and consume overexpressed H2S in colon cancer to inhabit tumor progression, providing a new way for oral drug treatment of colon cancer.


Assuntos
Neoplasias do Colo , Hidrogéis , Humanos , Hidrogéis/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Bactérias
12.
Clin Transl Med ; 13(1): e1129, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36650118

RESUMO

BACKGROUND: The therapeutic value of targeted therapies in patients with lung cancer is reduced when tumours acquire secondary resistance after an initial period of successful treatment. However, the molecular events behind the resistance to targeted therapies in lung cancer remain largely unknown. AIMS: To discover the important role and mechanism of lncRNA BC in promoting tumor metastasis and influencing clinical prognosis of LUAD. MATERIALS & METHODS: Microarrays were used to screen a comprehensive set of lncRNAs with differential expression profiles in lung cancer cells. The functional role and mechanism of lncRNA were further investigated by gain- and loss-of-function assays. RNA pull-down, protein assays, and mass spectrometry were used to identify proteins that interacted with lncRNA. TaqMan PCR was used to measure lncRNA in lung adenocarcinoma and adjacent nontumor tissues from 428 patients. The clinical significance of lncRNA identified was statistically confirmed in this cohort of patients. RESULTS: In this study, we show that the long non-coding RNA BC009639 (BC) is involved in acquired resistance to EGFR-targeted therapies. Among the 235 long non-coding RNAs that were differentially expressed in lung cancer cell lines, with different metastatic potentials, BC promoted growth, invasion, metastasis, and resistance to EGFR-tyrosine kinase inhibitors (EGFR-TKIs), both in vitro and in vivo. BC was highly expressed in 428 patients with lung adenocarcinoma (LUAD) and high BC expression correlated with reduced efficacy of EGFR-TKI therapy. To uncover the molecular mechanism of BC-mediated EGFR-TKI resistance in lung cancer, we screened and identified nucleolin and hnRNPK that interact with BC. BC formed the splicing complex with nucleolin and hnRNPK to facilitate the production of a non-protein-coding inositol monophosphatase domain containing 1 (IMPAD1) splice variant, instead of the protein-coding variant. The BC-mediated alternative splicing (AS) of IMPAD1 resulted in the induction of the epithelial-mesenchymal transition and resistance to EGFR-TKI in lung cancer. High BC expression correlated with clinical progress and poor survival among 402 patients with LUAD. DISSCUSSION: Through alternative splicing, BC boosted the non-coding IMPAD1-203 transcript variant while suppressing the IMPAD1-201 variant. In order to control the processing of pre-mRNA, BC not only attracted RNA binding proteins (NCL, IGF2BP1) or splicing factors (hnRNPK), but also controlled the formation of the splicing-regulator complex by creating RNA-RNA-duplexes. CONCLUSION: Our results reveal an important role for BC in mediating resistance to EGFR-targeted therapy in LUAD through IMPAD1 AS and in implication for the targeted therapy resistance.


Assuntos
Adenocarcinoma , Processamento Alternativo , Neoplasias Pulmonares , RNA Longo não Codificante , Humanos , Adenocarcinoma/genética , Adenocarcinoma/patologia , Processamento Alternativo/genética , Linhagem Celular Tumoral , Receptores ErbB/genética , Receptores ErbB/metabolismo , Pulmão/metabolismo , Neoplasias Pulmonares/patologia , RNA Longo não Codificante/metabolismo
13.
J Control Release ; 353: 591-610, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36503071

RESUMO

Intracellular Methicillin-Resistant Staphylococcus aureus (MRSA) remains a major factor of refractory and recurrent infections, which cannot be well addressed by antibiotic therapy. Here, we design a cellular infectious microenvironment-activatable polymeric nano-system to mediate targeted intracellular drug delivery for macrophage reprogramming and intracellular MRSA eradication. The polymeric nano-system is composed of a ferrocene-decorated polymeric nanovesicle formulated from poly(ferrocenemethyl methacrylate)-block-poly(2-methacryloyloxyethyl phosphorylcholine) (PFMMA-b-PMPC) copolymer with co-encapsulation of clofazimine (CFZ) and interferon-γ (IFN-γ). The cellular-targeting PMPC motifs render specific internalization by macrophages and allow efficient intracellular accumulation. Following the internalization, the ferrocene-derived polymer backbone sequentially undergoes hydrophobic-to-hydrophilic transition, charge reversal and Fe release in response to intracellular hydrogen peroxide over-produced upon infection, eventually triggering endosomal escape and on-site cytosolic drug delivery. The released IFN-γ reverses the immunosuppressive status of infected macrophages by reprogramming anti-inflammatory M2 to pro-inflammatory M1 phenotype. Meanwhile, intracellular Fe2+-mediated Fenton reaction together with antibiotic CFZ contributes to increased intracellular hydroxyl radical (•OH) generation. Ultimately, the nano-system achieves robust potency in ablating intracellular MRSA and antibiotic-tolerant persisters by synchronous immune modulation and efficient •OH killing, providing an innovative train of thought for intracellular MRSA control.


Assuntos
Antibacterianos , Macrófagos , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Interferon gama , Macrófagos/imunologia , Metalocenos/uso terapêutico , Staphylococcus aureus Resistente à Meticilina/imunologia , Polímeros/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/imunologia , Nanoestruturas/uso terapêutico
14.
Adv Sci (Weinh) ; 10(4): e2205480, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36479844

RESUMO

Systematic administration of antibiotics to treat infections often leads to the rapid evolution and spread of multidrug-resistant bacteria. Here, an in situ-formed biotherapeutic gel that controls multidrug-resistant bacterial infections and accelerates wound healing is reported. This biotherapeutic gel is constructed by incorporating stable microbial communities (kombucha) capable of producing antimicrobial substances and organic acids into thermosensitive Pluronic F127 (polyethylene-polypropylene glycol) solutions. Furthermore, it is found that the stable microbial communities-based biotherapeutic gel possesses a broad antimicrobial spectrum and strong antibacterial effects in diverse pathogenic bacteria-derived xenograft infection models, as well as in patient-derived multidrug-resistant bacterial xenograft infection models. The biotherapeutic gel system considerably outperforms the commercial broad-spectrum antibacterial gel (0.1% polyaminopropyl biguanide) in pathogen removal and infected wound healing. Collectively, this biotherapeutic strategy of exploiting stable symbiotic consortiums to repel pathogens provides a paradigm for developing efficient antibacterial biomaterials and overcomes the failure of antibiotics to treat multidrug-resistant bacterial infections.


Assuntos
Anti-Infecciosos , Infecções Bacterianas , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias , Poloxaleno/farmacologia , Infecções Bacterianas/tratamento farmacológico
15.
Nano Lett ; 22(21): 8608-8617, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36259687

RESUMO

The chemotherapeutic effectiveness of pancreatic ductal adenocarcinoma (PDAC) is severely hampered by insufficient intratumoral delivery of antitumor drugs. Here, we demonstrate that enhanced pancreatic cancer chemotherapy can be achieved by probiotic spore-based oral drug delivery system via gut-pancreas axis translocation. Clostridium butyricum spores resistant to harsh external stress are extracted as drug carriers, which are further covalently conjugated with gemcitabine-loaded mesoporous silicon nanoparticles (MGEM). The spore-based oral drug delivery system (SPORE-MGEM) migrates upstream into pancreatic tumors from the gut, which increases intratumoral drug accumulation by ∼3-fold compared with MGEM. In two orthotopic PDAC mice models, tumor growth is markedly suppressed by SPORE-MGEM without obvious side effects. Leveraging the biological contact of the gut-pancreas axis, this probiotic spore-based oral drug delivery system reveals a new avenue for enhancing PDAC chemotherapy.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Probióticos , Camundongos , Animais , Linhagem Celular Tumoral , Esporos Bacterianos , Carcinoma Ductal Pancreático/tratamento farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Sistemas de Liberação de Medicamentos , Pâncreas/patologia , Neoplasias Pancreáticas
16.
ACS Cent Sci ; 8(9): 1306-1317, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36188344

RESUMO

Clinical treatment efficacy of oral bacterial therapy has been largely limited by insufficient gut retention of probiotics. Here, we developed a bioorthogonal-mediated bacterial delivery strategy for enhancing probiotics colonization by modulating bacterial adhesion between probiotics and gut inhabitants. Metabolic amino acid engineering was applied to metabolically incorporate azido-decorated d-alanine into peptidoglycans of gut inhabitants, which could enable in situ bioorthogonal conjugation with dibenzocyclooctyne (DBCO)-modified probiotics. Both in vitro and in vivo studies demonstrated that the occurrence of the bioorthogonal reaction between azido- and DBCO-modified bacteria could result in obvious bacterial adhesion even in a complex physiological environment. DBCO-modified Clostridium butyricum (C. butyricum) also showed more efficient reservation in the gut and led to obvious disease relief in dextran sodium sulfate-induced colitis mice. This strategy highlights metabolically modified gut inhabitants as artificial reaction sites to bind with DBCO-decorated probiotics via bioorthogonal reactions, which shows great potential for enhancing bacterial colonization.

17.
Nano Lett ; 22(21): 8735-8743, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36286590

RESUMO

The chemotherapy efficacy of nanodrugs is restricted by poor tumor targeting and uptake. Here, an engineered biohybrid living material (designated as EcN@HPB) is constructed by integrating paclitaxel and BAY-876 bound human serum albumin nanodrugs (HPB) with Escherichia coli Nissle 1917 (EcN). Due to the inherent tumor tropism of EcN, EcN@HPB could actively target the tumor site and competitively deprive glucose through bacterial respiration. Thus, albumin would be used as an alternative nutrient source for tumor metabolism, which significantly promotes the internalization of HPB by tumor cells. Subsequently, BAY-876 internalized along with HPB nanodrugs would further depress glucose uptake of tumor cells via inhibiting glucose transporter 1 (GLUT1). Together, the decline of glucose bioavailability of tumor cells would activate and promote the macropinocytosis in an AMP-activated protein kinase (AMPK)-dependent manner, resulting in more uptake of HPB by tumor cells and boosting the therapeutic outcome of paclitaxel.


Assuntos
Infecções por Escherichia coli , Nanopartículas , Neoplasias , Humanos , Disponibilidade Biológica , Escherichia coli/genética , Escherichia coli/metabolismo , Glucose/metabolismo , Nanopartículas/uso terapêutico , Neoplasias/tratamento farmacológico , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico
18.
Front Oncol ; 12: 943761, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36033509

RESUMO

Objectives: The prognostic significance of acute lymphoblastic leukemia (ALL) patients with central nervous system leukemia (CNSL) at diagnosis is controversial. We aimed to determine the impact of CNSL at diagnosis on the clinical outcomes of childhood B-cell ALL in the South China Children's Leukemia Group (SCCLG). Methods: A total of 1,872 childhood patients were recruited for the study between October 2016 and July 2021. The diagnosis of CNSL depends on primary cytological examination of cerebrospinal fluid, clinical manifestations, and imaging manifestations. Patients with CNSL at diagnosis received two additional courses of intrathecal triple injections during induction. Results: The frequency of CNLS at the diagnosis of B-cell ALL was 3.6%. Patients with CNSL at diagnosis had a significantly higher mean presenting leukocyte count (P = 0.002) and poorer treatment response (P <0.05) compared with non-CNSL patients. Moreover, CNSL status was associated with worse 3-year event-free survival (P = 0.030) and a higher risk of 3-year cumulative incidence of relapse (P = 0.008), while no impact was observed on 3-year overall survival (P = 0.837). Multivariate analysis revealed that CNSL status at diagnosis was an independent predictor with a higher cumulative incidence of relapse (hazard ratio = 2.809, P = 0.016). Conclusion: CNSL status remains an adverse prognostic factor in childhood B-cell ALL, indicating that additional augmentation of CNS-directed therapy is warranted for patients with CNSL at diagnosis.

19.
Nanotechnology ; 33(42)2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35817015

RESUMO

Type II p-n heterojunction and direct Z-scheme heterojunction are identical staggered band alignments, but were reported ambiguously in many composite photocatalysts because their carriers migrate in opposite directions. In this research, metal oxides CuO, NiO and Co3O4-based heterojunctions with Na0.9Mg0.45Ti3.55O8(NMTO) were synthesized via a simple hydrothermal method. The CuO/NMTO heterojunction was demonstrated as a direct Z-scheme heterojunction, whereas the NiO/NMTO and Co3O4/NMTO heterojunctions showed type II p-n band alignment, distinguished by the direct observation of carrier migration under light illumination, and confirmed by the x-ray photoelectron spectroscopy, Mott-Schottky measurements, ultraviolet photoelectron spectra and capture experiments. These all heterojunctions enjoyed better photocatalytic performance to degrade methylene blue and antibiotics (Enrofloxacin, Metronidazole and tetracycline) than the pure NMTO, attributed to their effective separation of the photoinduced electron-hole pairs owing to the staggered band alignment. Prominently, the NiO/NMTO and Co3O4/NMTO p-n heterojunctions exhibited superior degradation ability to the CuO/NMTO Z-scheme heterojunction. The initial relative Fermi position of two semiconductors is the prerequisite to determine whether the p-n heterojunction or direct Z-scheme heterojunction is built because the electrons diffuse from one semiconductor with a higher Fermi level to another with a lower Fermi level while the holes diffuse reversely until a united Fermi level when they combine. The built-in electric field at the heterojunction interface is determined by the difference in the initial Fermi levels or work functions of two semiconductors, regulating the separation ability of photogenerated electrons and holes to affect the photocatalytic performance. Thus, the high difference in the initial Fermi levels of semiconductors is crucial in the development of heterojunctions with staggered band alignment to obtain high performance in photocatalytic reactions.

20.
Sci China Chem ; 65(6): 1010-1075, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35505924

RESUMO

Biomedical polymers have been extensively developed for promising applications in a lot of biomedical fields, such as therapeutic medicine delivery, disease detection and diagnosis, biosensing, regenerative medicine, and disease treatment. In this review, we summarize the most recent advances in the synthesis and application of biomedical polymers, and discuss the comprehensive understanding of their property-function relationship for corresponding biomedical applications. In particular, a few burgeoning bioactive polymers, such as peptide/biomembrane/microorganism/cell-based biomedical polymers, are also introduced and highlighted as the emerging biomaterials for cancer precision therapy. Furthermore, the foreseeable challenges and outlook of the development of more efficient, healthier and safer biomedical polymers are discussed. We wish this systemic and comprehensive review on highlighting frontier progress of biomedical polymers could inspire and promote new breakthrough in fundamental research and clinical translation.

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