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1.
Nat Commun ; 15(1): 3187, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622116

RESUMO

Transcription is crucial for the expression of genetic information and its efficient and accurate termination is required for all living organisms. Rho-dependent termination could rapidly terminate unwanted premature RNAs and play important roles in bacterial adaptation to changing environments. Although Rho has been discovered for about five decades, the regulation mechanisms of Rho-dependent termination are still not fully elucidated. Here we report that Rof is a conserved antiterminator and determine the cryogenic electron microscopy structure of Rho-Rof antitermination complex. Rof binds to the open-ring Rho hexamer and inhibits the initiation of Rho-dependent termination. Rof's N-terminal α-helix undergoes conformational changes upon binding with Rho, and is key in facilitating Rof-Rho interactions. Rof binds to Rho's primary binding site (PBS) and excludes Rho from binding with PBS ligand RNA at the initiation step. Further in vivo analyses in Salmonella Typhimurium show that Rof is required for virulence gene expression and host cell invasion, unveiling a physiological function of Rof and transcription termination in bacterial pathogenesis.


Assuntos
Fator Rho , Fatores de Transcrição , Fatores de Transcrição/metabolismo , Virulência/genética , Fator Rho/genética , Fator Rho/metabolismo , Regulação Bacteriana da Expressão Gênica , Transcrição Gênica , Bactérias/genética , Salmonella typhimurium/genética , Salmonella typhimurium/metabolismo
3.
J Leukoc Biol ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38626292

RESUMO

Conventional treatments have shown a limited efficacy for pancreatic cancer, and immunotherapy is an emerging option for treatment of this highly fatal malignancy. Neoantigen is critical to improving the efficacy of tumor-specific immunotherapy. The cancer and peripheral blood specimens from human leukocyte antigen (HLA)-A0201 positive pancreatic cancer patient were subjected to next-generation sequencing and bioinformatics analyses were performed to screen high-affinity and highly stable neoepitopes. The activation of cytotoxic T lymphocytes (CTLs) by the mutBCL2A111-20 neoepitope targeting B-cell lymphoma 2-related protein A1 (BCL2A1) mutant epitope was investigated, and the cytotoxicity of mutBCL2A111-20 neoepitope-specific CTLs to pancreatic cancer cells was evaluated. The mutBCL2A111-20 neoepitope was found to present a high immunogenicity and induce CTLs activation and proliferation, and was cytotoxic to mutBCL2A111-20 neoepitope-loaded T2 cells and pancreatic cancer PANC-1-Neo and A2-BxPC-3-Neo cells that overexpressed mutBCL2A111-20 neoepitopes, appearing a targeting neoepitope specificity. In addition, high BCL2A1 expression correlated with a low 5-year progress free interval (PFI) among pancreatic cancer patients. Our findings provide experimental supports to individualized T-cell therapy targeting mutBCL2A111-20 neoepitopes, and provide an option of immunotherapy for pancreatic cancer.

4.
JAMA Dermatol ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630453

RESUMO

This case report describes a 30-year-old man presenting with 1-year history of nonitchy red papules and patches who was subsequently treated with upadacitinib.

5.
PLoS Pathog ; 20(4): e1012123, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38607975

RESUMO

RAB GTPases (RABs) control intracellular membrane trafficking with high precision. In the present study, we carried out a short hairpin RNA (shRNA) screen focused on a library of 62 RABs during infection with porcine reproductive and respiratory syndrome virus 2 (PRRSV-2), a member of the family Arteriviridae. We found that 13 RABs negatively affect the yield of PRRSV-2 progeny virus, whereas 29 RABs have a positive impact on the yield of PRRSV-2 progeny virus. Further analysis revealed that PRRSV-2 infection transcriptionally regulated RAB18 through RIG-I/MAVS-mediated canonical NF-κB activation. Disrupting RAB18 expression led to the accumulation of lipid droplets (LDs), impaired LDs catabolism, and flawed viral replication and assembly. We also discovered that PRRSV-2 co-opts chaperone-mediated autophagy (CMA) for lipolysis via RAB18, as indicated by the enhanced associations between RAB18 and perlipin 2 (PLIN2), CMA-specific lysosomal associated membrane protein 2A (LAMP2A), and heat shock protein family A (Hsp70) member 8 (HSPA8/HSC70) during PRRSV-2 infection. Knockdown of HSPA8 and LAMP2A impacted on the yield of PRRSV-2 progeny virus, implying that the virus utilizes RAB18 to promote CMA-mediated lipolysis. Importantly, we determined that the C-terminal domain (CTD) of HSPA8 could bind to the switch II domain of RAB18, and the CTD of PLIN2 was capable of associating with HSPA8, suggesting that HSPA8 facilitates the interaction between RAB18 and PLIN2 in the CMA process. In summary, our findings elucidate how PRRSV-2 hijacks CMA-mediated lipid metabolism through innate immune activation to enhance the yield of progeny virus, offering novel insights for the development of anti-PRRSV-2 treatments.


Assuntos
Autofagia Mediada por Chaperonas , Vírus da Síndrome Respiratória e Reprodutiva Suína , Suínos , Animais , Lipólise , Regulação para Cima , Proteínas rab de Ligação ao GTP/genética , Glicoproteínas de Membrana Associadas ao Lisossomo , RNA Interferente Pequeno
6.
Mycoses ; 67(4): e13721, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38570912

RESUMO

BACKGROUND: Psoriatic patients may experience the coexistence of onychomycosis (OM). However, the evaluation of OM in psoriatics has been hindered by potential clinical differences from OM in non-psoriatics. OBJECTIVE: To assess and compare dermoscopic features between toenail OM in psoriatic and in non-psoriatic patients. PATIENTS AND METHODS: Between September 2020 and September 2023, dermoscopy was conducted on 183 affected toenails by OM in psoriatics and 232 affected toenails by OM in non-psoriatics in two centres. The dermoscopic characteristics were compared using the Chi-squared test. RESULTS: Among toenail OM cases in psoriatic subjects, the most prevalent dermoscopic features included pitting (147/183, 80.33%) and subungual hyperkeratosis (118/183, 64.48%). Conversely, toenail OM in non-psoriatics was characterized by subungual hyperkeratosis (175/232, 75.43%) and nail spikes (139/232, 59.91%). Comparative analysis revealed a significantly higher occurrence of pitting (80.33% vs. 15.96%, p < .001), periungual telangiectasis (22.40% vs. 4.74%, p < .001), oil patches (12.57% vs. 0.43%,p < .001) and transverse grooves (43.72% vs. 28.45%,p < .01) in toenail OM in psoriatics. Furthermore, toenail OM in psoriatics exhibited a significantly lower frequency of yellow structureless area (13.11% vs. 42.67%, p < .001), nail spikes (43.17% vs. 59.91%, p < .01), ruin appearance of sulphur nugget (8.20% vs. 31.03%, p < .001), dotted/blocky haemorrhage (6.01% vs. 20.69%,p < .001) and partial onycholysis (32.79% vs. 46.98%, p < .01). CONCLUSIONS: Dermoscopic features of toenail OM in psoriatic and non-psoriatic patients exhibit notable differences. OM in psoriatics shows a higher frequency of pitting and periungual telangiectasis, while a lower frequency of yellow structureless areas and nail spikes under dermoscopy.


Assuntos
Ceratose , Doenças da Unha , Onicomicose , Telangiectasia , Humanos , Onicomicose/epidemiologia , Onicomicose/complicações , Unhas , Estudos Prospectivos , Ceratose/complicações , Telangiectasia/complicações
7.
Artigo em Inglês | MEDLINE | ID: mdl-38576101

RESUMO

BACKGROUND: Ovarian cancer (OVCA) stands as one of the most fatal gynecological malignancies. Honokiol (HNK) has been substantiated by numerous studies for its anti-tumor activity against malignancies including OVCA. Consequently, this work was designed to elucidate the impact of HNK-mediated modulation of the YAP/TAZ pathway on the biological functions of OVCA cells. METHODS: OVCA cells were subjected to treatment with varying concentrations (0, 25, 50, 75, and 100 µM) of HNK, concomitant with the administration of YAP agonist (XMU). Assessment of cellular viability was executed employing the CCK-8 assay, while quantification of cellular proliferation transpired via colony formation assays. Apoptosis was ascertained using flow cytometry, and expression of apoptosis-related proteins (caspase-3, Bcl-2, Bax), EMT-related proteins (E-cadherin, N-cadherin), migration-associated proteins (MMP-2, MMP-9), and YAP/TAZ pathway-related proteins was evaluated by western blot. Transwell experiments were conducted to assess cellular migratory and invasive propensities. Xenograft tumor models were built to observe tumor growth (volume and weight), apoptosis was assessed by TUNEL staining, and Ki67 expression was evaluated through IHC. RESULTS: HNK exerted inhibitory effects on the viability and proliferative capacity of OVCA cells, elicited apoptotic responses, curtailed the migratory and invasive tendencies of cells, and downregulated the YAP/TAZ pathway. Stimulation with YAP agonist (XMU-MP-1) partially attenuated the impacts of HNK on OVCA cell biology. Experiments in vivo confirmed that HNK inhibited OVCA tumor growth. CONCLUSION: The outcomes of this investigation conclusively established that HNK orchestrated the modulation of the YAP/TAZ pathway, thereby exerting control over the malignant phenotypic manifestations of OVCA cells. The ascertained function of HNK in restraining cellular proliferation and tumor progression provided novel evidence of its anti-proliferative activity within OVCA cells.

8.
Nano Lett ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578061

RESUMO

Monolayer 2D semiconductors, such as WS2, exhibit uniquely strong light-matter interactions due to exciton resonances that enable atomically thin optical elements. Similar to geometry-dependent plasmon and Mie resonances, these intrinsic material resonances offer coherent and tunable light scattering. Thus far, the impact of the excitons' temporal dynamics on the performance of such excitonic metasurfaces remains unexplored. Here, we show how the excitonic decay rates dictate the focusing efficiency of an atomically thin lens carved directly out of exfoliated monolayer WS2. By isolating the coherent exciton radiation from the incoherent background in the focus of the lens, we obtain a direct measure of the role of exciton radiation in wavefront shaping. Furthermore, we investigate the influence of exciton-phonon scattering by characterizing the focusing efficiency as a function of temperature, demonstrating an increased optical efficiency at cryogenic temperatures. Our results provide valuable insights into the role of excitonic light scattering in 2D nanophotonic devices.

9.
Front Microbiol ; 15: 1361649, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38567079

RESUMO

Introduction: Air curing (AC) plays a crucial role in cigar tobacco leaf production. The AC environment is relatively mild, contributing to a diverse microbiome. Fungi are important components of the tobacco and environmental microbiota. However, our understanding of the composition and function of fungal communities in AC remains limited. Methods: In this study, changes in the chemical constituents and fungal community composition of cigar tobacco leaves during AC were evaluated using flow analysis and high-throughput sequencing. Results: The moisture, water-soluble sugar, starch, total nitrogen, and protein contents of tobacco leaves exhibited decreasing trends, whereas nicotine showed an initial increase, followed by a decline. As determined by high-throughput sequencing, fungal taxa differed among all stages of AC. Functional prediction showed that saprophytic fungi were the most prevalent type during the AC process and that the chemical composition of tobacco leaves is significantly correlated with saprophytic fungi. Conclusion: This study provides a deeper understanding of the dynamic changes in fungal communities during the AC process in cigar tobacco leaves and offers theoretical guidance for the application of microorganisms during the AC process.

10.
Opt Express ; 32(7): 11693-11714, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38571011

RESUMO

The foundation of an intelligent highway network is the construction of a high-density distributed strain monitoring system, which is based on sensing elements that can sensitively capture external information. In this research, the development and application for the structure of a novel strained optical fiber cable based on the weak fiber Bragg grating (wFBG) arrays are discussed. A modulation and demodulation solution of wavelength division multiplexing combined with time division multiplexing is developed by utilizing the property by which the wavelength of the strained optical fiber cable is periodically switched. Further, the strain transfer model of the optical cable is analyzed hierarchically using the theory of elasticity. The strain transfer coefficients of the overhanging region and the gluing region are combined to deduce the sensitivity model of the strained optical fiber cable. Moreover, the finite element technique is integrated to optimize the structural parameters of the optical cable for high-sensitivity or large-scale range. The strained optical fiber cable based on wFBG arrays is applied to a steel-concrete composite bridge. The static and dynamic loading tests show that the sensing optical cable can be monitored for strain variation in order to realize the functions of lane identification, weighing vehicle tonnage as well as velocity discrimination.

11.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(3): 321-324, 2024 Mar 15.
Artigo em Chinês | MEDLINE | ID: mdl-38557387

RESUMO

The male patient, one day old, was admitted to the hospital due to hypoglycemia accompanied by apnea appearing six hours after birth. The patient had transient hypoglycemia early after birth, and acute heart failure suddenly occurred on the eighth day after birth. Laboratory tests showed significantly reduced levels of adrenocorticotropic hormone and cortisol, and pituitary magnetic resonance imaging was normal. Genetic testing results showed that the patient had probably pathogenic compound heterozygous mutations of the TBX19 gene (c.917-2A>G+c.608C>T), inherited respectively from the parents. The patient was conclusively diagnosed with congenital isolated adrenocorticotropic hormone deficiency caused by mutation of the TBX19 gene. Upon initiating hydrocortisone replacement therapy, cardiac function rapidly returned to normal. After being discharged, the patient continued with the hydrocortisone replacement therapy. By the 18-month follow-up, the patient was growing and developing well. In neonates, unexplained acute heart failure requires caution for possible endocrine hereditary metabolic diseases, and timely cortisol testing and genetic testing should be conducted.


Assuntos
Insuficiência Adrenal , Insuficiência Cardíaca , Hipoglicemia , Recém-Nascido , Humanos , Masculino , Hidrocortisona/uso terapêutico , Hipoglicemia/etiologia , Insuficiência Adrenal/congênito , Insuficiência Adrenal/diagnóstico , Insuficiência Adrenal/genética , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/genética , Hormônio Adrenocorticotrópico
12.
Sci Rep ; 14(1): 7625, 2024 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561344

RESUMO

Stroke survivors frequently experience difficulties in daily activities, such as bathing, feeding, and mobility. This study aimed to evaluate the reliability and validity of a computer-adaptive test-Longshi scale (CAT-LS) for assessing activities of daily living (ADL) in stroke survivors. This cross-sectional study collected data using an electronic application. The ADL function of stroke survivors in rehabilitation departments of hospitals was assessed using both the CAT-LS and BI. Correlations between the CAT-LS and Barthel index (BI) and concurrent validity were evaluated using Pearson's correlation test and multiple linear regression. Interrater reliability was evaluated using the intraclass correlation coefficient based on a two-way random effect. The internal consistency of the CAT-LS was assessed using Cronbach's coefficient (α) and corrected item-total correlations. Overall, 103 medical institutions in China were used in this study. In total, 7151 patients with stroke were included in this study. The CAT-LS classified patients into three ADL groups (bedridden, domestic, and community) with significantly different BI scores (P < 0.05). The CAT-LS results obtained using the decision-tree scoring model were consistent with the scores for each BI item. A strong correlation was observed between CAT-LS and BI (Pearson's r: 0.6-0.894, P < 0.001). The CAT-LS demonstrated good internal consistency (Cronbach's α, 0.803-0.894) and interrater reliability (ICC, 0.928-0.979). CAT-LS is time-efficient and requires < 1 min to administer. The CAT-LS is a reliable and valid tool for assessing ADL function in stroke survivors and can provide rapid and accurate assessments that reduce the burden on healthcare professionals. Further validation of this tool in other populations and settings is necessary.Study registration number: No.: ChiCTR2000034067; http://www.chictr.org.cn/showproj.aspx?proj=54770 .


Assuntos
Atividades Cotidianas , Acidente Vascular Cerebral , Humanos , Estudos Transversais , Reprodutibilidade dos Testes , Sobreviventes
13.
BMC Nurs ; 23(1): 224, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561758

RESUMO

BACKGROUND: Mental health problems are critical and common in medical staff working in Intensive Care Units (ICU) even at the late stage of COVID-19, particularly for nurses. There is little research to explore the inner relationships between common syndromes, such as depression and burnout. Network analysis (NA) was a novel approach to quantified the correlations between mental variables from the perspective of mathematics. This study was to investigate the interactions between burnout and depression symptoms through NA among ICU nurses. METHOD: A cross-sectional study with a total of 616 Chinese nurses in ICU were carried out by convenience sampling from December 19, 2022 to January19, 2023 via online survey. Burnout symptoms were measured by Maslach Burnout Inventory-General Survey (MBI-GS) (Chinese version), and depressive symptoms were assessed by the 9-item Patient Health Questionnaire (PHQ-9). NA was applied to build interactions between burnout and depression symptoms. We identified central and bridge symptoms by R package qgraph in the network model. R package bootnet was used to examined the stability of network structure. RESULTS: The prevalence of burnout and depressive symptoms were 48.2% and 64.1%, respectively. Within depression-burnout network, PHQ4(Fatigue)-MBI2(Used up) and PHQ4(Fatigue)-MBI5(Breakdown) showed stronger associations. MBI2(Used up) had the strongest expected influence central symptoms, followed by MBI4(Stressed) and MBI7 (Less enthusiastic). For bridge symptoms. PHQ4(Fatigue), MBI5(Breakdown) and MBI2(Used up) weighed highest. Both correlation stability coefficients of central and bridge symptoms in the network structure were 0.68, showing a high excellent level of stability. CONCLUSION: The symptom of PHQ4(Fatigue) was the bridge to connect the emotion exhaustion and depression. Targeting this symptom will be effective to detect mental disorders and relieve mental syndromes of ICU nurses at the late stage of COVID-19 pandemic.

14.
Biomaterials ; 308: 122565, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38603823

RESUMO

As bacterial keratitis progresses rapidly, prompt intervention is necessary. Current diagnostic processes are time-consuming and invasive, leading to improper antibiotics for treatment. Therefore, innovative strategies for diagnosing and treating bacterial keratitis are urgently needed. In this study, Cu2-xSe@BSA@NTRP nanoparticles were developed by loading nitroreductase-responsive probes (NTRPs) onto Cu2-xSe@BSA. These nanoparticles exhibited integrated fluorescence imaging and antibacterial capabilities. In vitro and in vivo experiments showed that the nanoparticles produced responsive fluorescence signals in bacteria within 30 min due to an interaction between the released NTRP and bacterial endogenous nitroreductase (NTR). When combined with low-temperature photothermal therapy (PTT), the nanoparticles effectively eliminated E. coli and S. aureus, achieved antibacterial efficacy above 95% and facilitated the re-epithelialization process at the corneal wound site in vivo. Overall, the Cu2-xSe@BSA@NTRP nanoparticles demonstrated potential for rapid, noninvasive in situ diagnosis, treatment, and visualization assessment of therapy effectiveness in bacterial keratitis.

15.
Curr Probl Cardiol ; : 102572, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38604416

RESUMO

One of the most common micro vascular complications of diabetes is diabetic peripheral neuropathy (DPN). The well-recognized risk factors for DPN are hyperglycemia, dyslipidemia, and hypertension. DPN is associated with a high mortality rate and poor prognosis. Its pathogenesis is not fully understood, and clinical treatment is focused on relieving its clinical symptoms, as well as improving blood sugar control and cardiovascular risk factors. DPN and its clinically effective treatments need to be studied. Microvascular complications of diabetes present a significant challenge due to their diverse presentations, significant morbidity, and as strong predictors of cardiovascular disease. Prevention and management strategies should focus on lifestyle modification, education and awareness, systematic screening for early complications, and intensive management of modifiable risk factors. There was an association between DPN and DKD as well as CVD, BMI and age demonstrated. These may indicate that in case of having one diabetes complication diagnosed, it is important to screen for others, including macrovascular ones, as they may be undiagnosed due to their "silent" nature. Further studies are expected to strengthen basic research on the subject, reveal modern medical mechanisms, and provide fresh ideas and innovative methods for the treatment of DPN.

16.
Artigo em Inglês | MEDLINE | ID: mdl-38607191

RESUMO

Background: Repeated episodes of jaundice and pruritus are common in a group of autosomal recessive liver diseases known as benign recurrent intrahepatic cholestasis. Benign recurrent intrahepatic cholestasis (BRIC) is divided into two types, type 1 and type 2, and is caused by mutations in the ATP8B1 and ABCB11 genes. Here, we report a rare case of BRIC type 2 mutation. Case presentation: A 45-year-old Chinese man had three frequent episodes of jaundice marked by extensive excoriation and severe pruritis, although he had no prior history of jaundice. Laboratory investigations showed no evidence of liver damage caused by viral, autoimmune, or acquired metabolic etiologies. The CT scan revealed an enlarged gallbladder with numerous punctate high-density shadows, while no wall thickening was observed. Endoscopic ultrasonography showed no evidence of dilation of the intrahepatic and extrahepatic bile duct, as well as the absence of gallstone. Diagnostic evaluation: Immunohistochemical examinations of liver biopsy samples showed cytokeratin-7 positive hepatocytes, suggesting chronic intrahepatic cholestasis. The reticulin fiberstaining demonstrated that the portions of the hepatic plate in the center of the lobule were asymmetrically organized,and somewhat enlarged, with collapsed areas indicating intralobular inflammation. Moreover, there were areas of collapse that indicated the presence of intralobular inflammation. Whole exome sequencing revealed mutations in the ABCB11 gene; c.3084A>G, p.A1028A homozygous mutation (chr2-169789016), and c.2594C>T, p.A865V heterozygous mutation (chr2-169801131). Based on these findings, the final diagnosis of the patient was metabolism-related jaundice. Treatment: Apart from receiving tapering dosage of prednisone to lower bilirubin levels, the patient received no extra care. Conclusion: The comprehensive diagnosis of a middle-aged male patient with BRIC-2, which involved extensive radiological, hematological, and genetic investigations, informed a tailored tapering prednisone regimen, highlighting the importance of personalized medicine in managing atypical presentations of this rare cholestatic disorder.

17.
Environ Microbiome ; 19(1): 22, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589941

RESUMO

BACKGROUND: Most researches on sponge holobionts focus primarily on symbiotic microbes, yet data at the level of the sponge hologenome are still relatively scarce. Understanding of the sponge host and its microbial gene expression profiles and the host-microbes interplay in different niches represents a key aspect of sponge hologenome. Using the Hawaiian demosponge Mycale grandis in different niches as a model, i.e. on rocks, on the surface of coral Porites compressa, under alga Gracilaria salicornia, we compared the bacterial and fungal community structure, functional gene diversity, expression pattern and the host transcriptome by integrating open-format (deep sequencing) and closed-format (GeoChip microarray) high-throughput techniques. RESULTS: Little inter-niche variation in bacterial and fungal phylogenetic diversity was detected for M. grandis in different niches, but a clear niche-dependent variability in the functional gene diversity and expression pattern of M. grandis host and its symbiotic microbiota was uncovered by GeoChip microarray and transcriptome analyses. Particularly, sponge host genes related to innate immunity and microbial recognition showed a strong correlation with the microbial symbionts' functional gene diversity and transcriptional richness in different niches. The cross-niche variability with respect to the symbiont functional gene diversity and the transcriptional richness of M. grandis holobiont putatively reflects the interplay of niche-specific selective pressure and the symbiont functional diversity. CONCLUSIONS: Niche-dependent gene expression profiles of M. grandis hologenome and the host-microbes interplay were suggested though little inter-niche variation in bacterial and fungal diversity was detected, particularly the sponge innate immunity was found to be closely related to the symbiotic microbes. Altogether, these findings provide novel insights into the black box of one sponge holobiont in different niches at the hologenome level.

18.
Colloids Surf B Biointerfaces ; 239: 113882, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38593511

RESUMO

Bacterial infections threaten public health, and novel therapeutic strategies critically demand to be explored. Herein, poly(amino acid) (PAA)-based drug delivery nanoparticles (NPs) were designed for eliminating Methicillin resistant Staphylococcus aureus (MRSA) via tunable release of antibiotic. Using N-acryloyl amino acids (valine, valine methyl ester, aspartic acid, serine) as monomers, four kinds of amphiphilic PAAs were synthesized via photoinduced electron/energy transfer-reversible addition fragmentation chain-transfer (PET-RAFT) polymerization and were further assembled into nano-sized delivery systems. Their assemble behavior was drove mainly by hydrophobic/hydrophilic interaction, which determined the particle size, efficacy of drug loading and release; but numerous hydrogen bonding (HB) interaction also played an important role in regulating morphologies of the NPs and enriching drug-binding capacity. By changing the HB- and hydrophobic-interaction of the PAAs, the particle sizes (240.7 nm-302.7 nm), the drug loading efficiency (9.57%-19.76%), and the Rifampicin (Rif) release rate (49.6%-69.7%) of the PAA-based NPs could be tunable. Specially, the antimicrobial properties of the Rif-loaded NPs are found to be related to the release of Rif, which was determined by its hydrophobic interaction with hydrophobic blocks and HB interaction with hydrophilic blocks. These studies provide a new outlook for the design of delivery systems for the therapy of bacterial infection.

20.
Food Sci Biotechnol ; 33(6): 1359-1369, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38585560

RESUMO

An antibacterial nano-hydrogel (ginger essential oil nanoemulsion hydrogel, GEONH) based on Schiff base reaction was prepared using double-formaldehyde micro fibrillated cellulose (DAMFC) and carboxymethyl chitosan (CMCS) loaded with ginger essential oil nanoemulsion (GEON). It was found that when the mass ratio of DAMFC/CMCS/GEON was 1/9/270, the gel time, the water absorbency, gel strength, and morphology were the best. The results of X-ray diffraction and FT-IR confirmed that the aldehyde group on the DAMFC molecular chain formed a stable chemical crosslinking with the amino group on the CMCS molecular chain, resulting in a change in the crystal structure. GEONH showed excellent bactericidal activity against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. Simultaneously, the prepared GEONH decreased the total viable count, Malondialdehyde, and total sulfhydryl content and improved the taste in the storage of boiled salted duck. Therefore, GEONH film is a promising fresh-keeping packaging for storing meat products. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-023-01437-4.

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