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1.
Infect Immun ; 92(4): e0048323, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38501672

RESUMO

Aspergillus fumigatus (A. fumigatus) is one of the common pathogens of fungal keratitis. Fungal growth and invasion cause excessive inflammation and corneal damage, leading to severe vision loss. Neutrophils are the primary infiltrating cells critical for fungal clearance. Cathelicidin [LL-37 in humans and cathelicidin-related antimicrobial peptide (CRAMP) in mice], a natural antimicrobial peptide, can directly inhibit the growth of many pathogens and regulate immune responses. However, the role of cathelicidin and its effect on neutrophils in A. fumigatus keratitis remain unclear. By establishing A. fumigatus keratitis mouse models, we found that cathelicidin was increased in A. fumigatus keratitis. It could reduce fungal loads, lower clinical scores, and improve corneal transparency. Restriction of CRAMP on fungal proliferation was largely counteracted in CD18-/- mice, in which neutrophils cannot migrate into infected sites. When WT neutrophils were transferred into CD18-/- mice, corneal fungal loads were distinctly reduced, indicating that neutrophils are vital for CRAMP-mediated resistance. Furthermore, cathelicidin promoted neutrophils to phagocytose and degrade conidia both in vitro and in vivo. CXC chemokine receptor 2 (CXCR2) was reported to be a functional receptor of LL-37 on neutrophils. CXCR2 antagonist SB225002 or phospholipase C (PLC) inhibitor U73122 weakened LL-37-induced phagocytosis. Meanwhile, LL-37 induced PLC γ phosphorylation, which was attenuated by SB225002. SB225002 or the autophagy inhibitors Bafilomycin-A1 and 3-Methyladenine weakened LL-37-induced degradation of conidia. Transmission electron microscopy (TEM) observed that LL-37 increased autophagosomes in Aspergillus-infected neutrophils. Consistently, LL-37 elevated autophagy-associated protein expressions (Beclin-1 and LC3-II), but this effect was weakened by SB225002. Collectively, cathelicidin reduces fungal loads and improves the prognosis of A. fumigatus keratitis. Both in vitro and in vivo, cathelicidin promotes neutrophils to phagocytose and degrade conidia. LL-37/CXCR2 activates PLC γ to amplify neutrophils' phagocytosis and induces autophagy to eliminate intracellular conidia.


Assuntos
Aspergillus fumigatus , Ceratite , Compostos de Fenilureia , Humanos , Animais , Camundongos , Neutrófilos , Antifúngicos/metabolismo , Catelicidinas , Fosfolipase C gama/metabolismo , Ceratite/microbiologia , Prognóstico , Camundongos Endogâmicos C57BL
2.
Bioorg Med Chem Lett ; 28(10): 1864-1869, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29650293

RESUMO

Sortase A (SrtA) anchors surface proteins to the cell wall and aids biofilm formation during infection, which functions as a key virulence factor of important Gram-positive pathogens, such as Staphylococcus aureus. At present researchers need a way in which to validate whether or not SrtA is a druggable target alternative to the conventional antibiotic targets in the mechanism. In this study, we performed a high-throughput screening and identified a new class of potential inhibitors of S. aureus SrtA, which are derived from natural products and contain the quinone skeleton. Compound 283 functions as an irreversible inhibitor that covalently alkylates the active site Cys184 of SrtA. NMR analysis confirms the direct interaction of the small-molecule inhibitor towards SrtA protein. The anchoring of protein A (SpA) to the cell wall and the biofilm formation are significantly attenuated when the S. aureus Newman strain is cultured in the presence of inhibitor. Our study indicates that compound 283 could be a potential hit for the development of new anti-virulence agents against S. aureus infections by covalently targeting SrtA.


Assuntos
Aminoaciltransferases/antagonistas & inibidores , Proteínas de Bactérias/antagonistas & inibidores , Benzoquinonas/química , Inibidores de Cisteína Proteinase/química , Aminoaciltransferases/metabolismo , Proteínas de Bactérias/metabolismo , Parede Celular/metabolismo , Cisteína Endopeptidases/metabolismo , Inibidores de Cisteína Proteinase/metabolismo , Inibidores de Cisteína Proteinase/farmacologia , Transferência Ressonante de Energia de Fluorescência , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Peptídeos/análise , Ligação Proteica , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/enzimologia
3.
Animals (Basel) ; 14(7)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38612327

RESUMO

Comprehensively understanding the spatial ecology and habitat preferences of endangered species is essential for population restoration and conservation. We investigated the home range and movement of the endangered Amur soft-shell turtle (Pelodiscus maackii) in the Ussuri River, Heilongjiang Province, Northeastern China. The study involved tracking 19 Amur soft-shell turtles from late June to mid-October, 2022, resulting in complete and partial home range size data for eight subadults and two adults, respectively. The primary analysis focused on eight subadults, and the models that best described daily movement were identified. We also explored the potential factors influencing home range size. The mean movement rate ranged from 39.18 ± 20.04 m/day to 72.45 ± 29.36 m/day and was positively correlated with the linear home range and water temperature. The most enlightening estimation of home range was derived from a 95% kernel density estimate, utilizing likelihood cross-validation smoothing while adhering to constraints delineated by the river boundaries. The average size of the home range was determined to be 1.02 hectares and displayed no correlation with body size. Subadults tended to establish well-defined home ranges over time, whereas defining home ranges for adults proved challenging. This research addresses a gap regarding the ecology of the Amur soft-shell turtle and provides a foundation for future conservation plans.

4.
Endocrine ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38955861

RESUMO

Immune checkpoint inhibitors (ICIs) have become extensively utilized in the early-stage treatment of various cancers, offering additional therapeutic possibilities for patients with advanced cancer. However, certain patient populations are susceptible to experiencing toxic adverse effects from ICIs, such as thyrotoxicosis, rashes, among others. Specifically, ICIDM, induced by immune checkpoint inhibitors, exhibits characteristics similar to insulin-dependent diabetes mellitus (Type 1 Diabetes Mellitus, T1DM). ICIDM is characterized by a rapid onset and may coincide with severe ketoacidosis. Despite a favorable response to insulin therapy, patients typically require lifelong insulin dependence. After discussing the autoimmune adverse effects and the specifics of ICIs-induced diabetes mellitus (ICIDM), it is important to note that certain patient populations are particularly susceptible to experiencing toxic adverse effects from ICIs. Specifically, ICIDM, which is triggered by immune checkpoint inhibitors, mirrors the characteristics of insulin-dependent diabetes mellitus (Type 1 Diabetes Mellitus, T1DM). This article conducts an in-depth analysis of the literature to explore the pathogenesis, disease progression, and treatment strategies applicable to diabetes induced by immune checkpoint inhibitors (ICIDM).

5.
Mol Med Rep ; 28(6)2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37888611

RESUMO

Intraoperative radiotherapy (IORT) is a precise, single high­dose irradiation directly targeting the tumor bed during surgery. In comparison with traditional external beam RT, it minimizes damage to other normal tissues, ensures an adequate dose to the tumor bed and results in improved cosmetic outcomes and quality of life. Furthermore, IORT offers a shorter treatment duration, lower economic costs and therapeutic efficacy comparable with traditional RT. However, its relatively higher local recurrence rate limits its further clinical applications. Identifying effective radiosensitizing drugs and rational RT protocols will improve its advantages. Furthermore, IORT may not only damage DNA to directly kill breast tumor cells but also alter the tumor microenvironment (TME) to exert a sustained antitumor effect. Specific doses of IORT may exert anti­angiogenic effects, and consequently antitumor effects, by impacting post­radiation peripheral blood levels of vascular endothelial growth factor and delta­like 4. IORT may also modify the postoperative wound fluid composition to continuously inhibit tumor growth, e.g. by reducing components such as microRNA (miR)­21, miR­221, miR­115, oncostatin M, TNF­ß, IL­6 and IL­8, and by elevating levels of components such as miR­223, to inhibit the ability of postoperative wound fluid to induce proliferation, invasion and migration of residual cancer cells. IORT can also modify cancer cell glucose metabolism to inhibit the proliferation of residual tumor cells. In addition, IORT can induce a bystander effect, eliminating the postoperative wound fluid­induced epithelial­mesenchymal transition and tumor stem cell phenotype. Insights gained at the molecular level may provide new directions for identifying novel therapeutic targets and approaches. A more comprehensive understanding of the effects of IORT on the breast cancer (BC) TME may further its clinical application. Hence, the present article reviews the primary effects of IORT on BC and its impact on the TME, aiming to offer fresh research perspectives for relevant professionals.


Assuntos
Neoplasias da Mama , MicroRNAs , Humanos , Feminino , Neoplasias da Mama/genética , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Microambiente Tumoral , Qualidade de Vida , Fator A de Crescimento do Endotélio Vascular
6.
J Cancer Res Clin Oncol ; 149(12): 10109-10117, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37264265

RESUMO

PURPOSE: In this study, we aimed to explore the potential significance of AR expression in HER2-positive breast cancer patients who underwent neoadjuvant targeted therapy. Specifically, we investigated the correlation between AR expression levels and pathological complete response (pCR) rates. Our objective was to determine whether there were significant differences in pCR rates among HER2-positive breast cancer patients with different levels of AR expression. METHODS: We conducted a retrospective analysis of 258 HER-2 positive breast cancer patients who underwent neoadjuvant dual-blocked standard therapy (following the NCCN Guideline 2021) at three breast cancer centers in southwest China. We analyzed the clinicopathological features and pCR rates of these patients. The cut-off value for AR expression level was calculated as the median value of 70%. We used the chi-square test to investigate the correlation between AR expression level and pCR rate, as well as other clinicopathological features. RESULTS: Out of the 258 patients analyzed, 154 (59.69%) achieved pCR. Based on the cut-off value of 70%, AR expression level was classified as low (AR ≤ 70%) or high (AR > 70%) expression. Our analysis revealed a significant correlation between AR expression level and pCR rate in HER2-positive breast cancer patients (P = 0.031). We also found a significant association between pCR rate and clinical stage (P = 0.033) and chemotherapy regimen (P = 0.034). Furthermore, subgroup analyses showed that the pCR rate was higher in patients with high AR expression levels compared to those with low AR expression levels. Additionally, we observed that patients with an ER/AR ratio of less than 1 had a higher pCR rate than those with an ER/AR ratio greater than 1 (P = 0.038). CONCLUSION: Our study findings suggest that HER2-positive breast cancer patients with high AR expression levels may achieve higher pCR rates when treated with neoadjuvant dual-blocked therapy. Overall, our results support the idea that AR expression levels have a significant correlation with pCR rates in HER2-positive breast cancer patients receiving this particular form of treatment.


Assuntos
Neoplasias da Mama , Receptores Androgênicos , Feminino , Humanos , Androgênios , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Terapia Neoadjuvante , Receptor ErbB-2/metabolismo , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Estudos Retrospectivos
7.
J Nanosci Nanotechnol ; 21(3): 1549-1559, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33404418

RESUMO

Cellulose acetate (CA) fibrous membranes blended with poly-(γ-glutamic acid) (γ-PGA) and ZnO were produced via electrospinning. The performance of the obtained composite membrane was investigated by scanning electron microscopy (SEM), Fourier transform IR spectroscopy, tensile test, water contact angle, and thermogravimetric analysis. The corn plant height, leaf area and SPAD (soil and plant analyzer development) were compared with plants covered with CA/γ-PGA and CA/γ-PGA/ZnO fibrous membranes at room temperature. Simultaneously, the water absorption and degradation rate were also studied. The results obtained indicate the potential use of these fibrous membranes for mulching film applications. The fibrous membranes could also find potential use as a material for food packing, facial mask and as antimicrobial films for wound dressing.

8.
RSC Adv ; 8(48): 27304-27317, 2018 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35539979

RESUMO

Poly(ether ether ketone)/zinc oxide (PEEK/ZnO) composites were manufactured by using the injection molding technique. Before blending with the PEEK resin matrix, some ZnO nanoparticles were modified by γ-aminopropyltriethoxylsilane (APTES). The effect of surface modification of ZnO nanoparticles by amino groups and Si-O bonds was investigated. PEEK/ZnO composites were characterized by scanning electron microscopy (SEM), thermogravimetric analysis, and X-ray diffraction. The scanning electron micrographs showed that ZnO nanoparticles were encapsulated in the PEEK phase; within this phase, the nanoparticles were homogeneously dispersed. Mechanical and tribological properties were measured by tensile strength, flexural strength, coefficient of friction, and wear rate. It was shown that the interfacial compatibility between ZnO nanoparticles and PEEK matrix was significantly enhanced due to the amino and Si-O bonds decorated on the ZnO nanoparticles. More importantly, the thermal stability of PEEK improved upon the incorporation of ZnO nanoparticles into this matrix. Cell viability studies with mouse osteoblasts demonstrated that cell growth on PEEK and PEEK/ZnO was significantly enhanced. On the basis of the obtained results, PEEK/ZnO composites are recommended as promising candidates for orthopaedic materials and trauma implants.

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