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1.
Clin Cosmet Investig Dermatol ; 17: 961-966, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38707607

RESUMO

Xanthomas are well-circumscribed skin lesions that are commonly seen in patients with familial hypercholesterolemia (FH). The aim of this report is to present a rare case of multiple large tuberous and tendinous xanthomas. A 17-year-old female patient in this report presented with multiple asymptomatic and papulo-nodular masses in both sides of palms, elbows, buttocks, knees, and Achilles tendons. Surgical removal of the masses was carried out in combination with lipid-lowering therapy. A following up of 3 months showed all wounds were healing well, and no recurrence of masses was observed. Therefore, for patients with xanthomas related with familial hypercholesterolaemia, lipid-lowering therapy has reportedly reduced the size of masses, but surgical treatment may be essential for large xanthomas caused pain or limitation of daily activities.

2.
Adv Sci (Weinh) ; : e2402429, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38751149

RESUMO

Axially chiral thioethers and sulfoxides emerge as two pivotal classes of ligands and organocatalysts, which have remarkable features in the stereoinduction of various asymmetric transformations. However, the lack of easy methods to access such molecules with diverse structures has hampered their broader utilization. Herein, an oxidative kinetic resolution for sulfides using a chiral bifunctional squaramide as the catalyst with cumene hydroperoxide as the terminal oxidant is established. This asymmetric approach provides a variety of axially chiral thioethers as well as sulfoxides bearing both axial and central chirality, with excellent diastereo- and enantioselectivities. This catalytic system also successfully extends to the kinetic resolution of benzothiophene-based sulfides. Preliminary mechanism investigation indicates that the multiple hydrogen bonding interactions between the bifunctional squaramide catalyst and substrates play a crucial role in determining the enantioselectivity and reactivity.

3.
Int J Nurs Sci ; 11(1): 106-112, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38352293

RESUMO

Objective: This study aimed to translate and evaluate the psychometric properties of the Perinatal Missed Care Survey in China. Methods: The Perinatal Missed Care Survey was translated according to the guidelines of the cross-cultural debugging scale recommended by the American Academy of Orthopaedic Surgeons Evidence-Based Medicine Committee, including forward translation, back translation, cultural adaption, and content validation, and its Chinese version was used in a cross-sectional study conducted from February to April in 2023. A total of 491 midwives from 14 different level hospitals in southwest China were recruited through a convenience sampling method. The discrimination ability of the items was tested through item analysis, and construct validity was assessed through exploratory factory and confirmatory factor analyses. The content validity index and Cronbach's α coefficients evaluated content validity and reliability, respectively. Results: The Chinese version's item-total correlation coefficients ranged from 0.641 to 0.866 in part A and from 0.644 to 0.819 in part B (P < 0.001). Parts A and B's scale-level content validity indexes were 0.95, and the item-level content validity indexes were from 0.86 to 1.00. The three common factors of part A (necessary care, basic care, and postnatal care) and part B (communication, labor resources, and material resources) were extracted, accounting for 70.186% and 71.984% of the total variance, respectively. Confirmatory factor analysis indicated that the good fit of the three-factor models was acceptable. The Cronbach's α coefficients were 0.968 (part A) and 0.940 (part B). Conclusion: The Chinese version of the Perinatal Missed Care Survey is a reliable and valid instrument for assessing nursing care missed by midwives during labor and birth and the reasons it was missed. Studies with large sample sizes are needed to verify the instrument's applicability in China.

4.
ACS Appl Bio Mater ; 7(2): 1125-1134, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38319146

RESUMO

Cutaneous trauma repair is still a challenge in the clinic due to the scar formation and slow healing rate, especially for diabetic patients. Various drug-loading wound dressings have been explored to solve this problem. Mesenchymal stem cell (MSC)-derived exosomes have been considered as a potential cell-free drug because of their anti-inflammation function and tissue repair property that are comparable to that of MSCs. Herein, a composite wound dressing (Exo/Gel) consisting of the chitosan hydrogel and adipose MSC-derived exosome (ADMSC-Exo) was designed and fabricated by a physical mixing method to promote the skin full-thickness wound repair. The exosomes were slowly released from the Exo/Gel dressing with the degradation of the chitosan hydrogel. The Exo/Gel displayed enhanced cell migration and angiogenic properties in vitro. And the results in the rat skin wound model showed that the Exo/Gel could promote the regular collagen deposition, angiogenesis, and hair follicle mosaicism regeneration. These results proved that the hydrogel dressing with ADMSCs-derived exosomes can accelerate skin wound healing, which is a strategy for developing wound dressings.


Assuntos
Quitosana , Exossomos , Células-Tronco Mesenquimais , Humanos , Ratos , Animais , Cicatrização , Hidrogéis/metabolismo , Exossomos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Bandagens
5.
Int J Biol Macromol ; 257(Pt 1): 127864, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37939762

RESUMO

Customized control of the biological response between the material matrix and cells is a crucial aspect in the development of the next generation of collagen materials. This study aims to investigate the effects of ultrahigh pressure treatment on the interaction between collagen and cells by subjecting bovine tendon collagen to different intensities of ultrahigh pressure field. The results indicate that ultrahigh pressure treatment alters the spatial folding of collagen, causing distortion of its triple helical conformation and exposing more free amino groups and hydrophobic regions. As a result, collagen's cell adhesion capability and ability to promote cell migration are significantly enhanced. Optimal cell adhesion and migration capabilities are observed in collagen samples treated at 500 MPa for 15 min. However, further increasing the intensity of the ultrahigh pressure treatment leads to severe damage to the triple-helical structure of collagen, along with re-aggregation of free amino groups and hydrophobic moieties, thereby reducing collagen's cell adhesion capability and ability to promote cell migration. Therefore, ultrahigh pressure treatment offers a promising method to effectively regulate collagen-cell adhesion and promote cell migration without the need for external components. This provides a potential means for the customized enhancement of collagen-based material interfaces.


Assuntos
Colágeno , Animais , Bovinos , Adesão Celular , Colágeno/química , Movimento Celular
6.
Macromol Biosci ; 24(2): e2300165, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37681479

RESUMO

Full-thickness skin defect has always been a major challenge in clinics due to fibrous hyperplasia in the repair process. Hydrogel composite dressings loaded with anti-fibrotic drugs have been considered as a promising strategy for scarless skin regeneration. In this work, a hydrogel composite (VP-CMCS-OSA) of carboxymethyl chitosan (CMCS) and oxidized sodium alginate (OSA), with loading anti-fibrotic drug verteporfin (VP), is developed based on two-step chemical reactions. Verteporfin is bonded with carboxymethyl chitosan through EDC/NHS treatment to form VP-CMCS, and then VP-CMCS is crosslinked with oxidized sodium alginate by Schiff base reaction to form VP-CMCS-OSA hydrogel. The characterization by SEM, FTIR, and UV-Vis shows the microstructure and chemical bonding of VP-CMCS-OSA. VP-CMCS-OSA hydrogel demonstrates the properties of high tissue adhesion, strong self-healing, and tensile ability. In the full-thickness skin defect model, the VP-CMCS-OSA composite hydrogels hasten wound healing due to the synergistic effects of hydrogels and verteporfin administration. The histological examination reveals the regular collagen arrangement and more skin appendages after VP-CMCS-OSA composite hydrogel treatment, indicating the full-thickness skin regeneration without potential scar formation. The outcomes suggest that the verteporfin-loaded composite hydrogel could be a potential method for scarless skin regeneration.


Assuntos
Quitosana , Hidrogéis , Hidrogéis/farmacologia , Hidrogéis/química , Quitosana/farmacologia , Quitosana/química , Verteporfina/farmacologia , Alginatos/farmacologia , Alginatos/química , Regeneração , Antibacterianos/farmacologia
7.
Org Lett ; 26(1): 153-159, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38133484

RESUMO

Aiming at the reported chiral synthons leading to manzacidins A and D, here we report a highly efficient catalytic asymmetric α-allenylic alkylation reaction of NH2-unprotected amino acid esters that is promoted by combined chiral aldehyde/palladium catalysis. Fifty examples of unnatural α,α-disubstituted amino acid esters are reported with good-to-excellent yields and stereoselectivities. Based on this methodology, a key intermediate leading to manzacidin C and its other three stereoisomers is prepared accordingly.

8.
Molecules ; 28(22)2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38005397

RESUMO

Traumatic nerve defects result in dysfunctions of sensory and motor nerves and are usually accompanied by pain. Nerve guidance conduits (NGCs) are widely applied to bridge large-gap nerve defects. However, few NGCs can truly replace autologous nerve grafts to achieve comprehensive neural regeneration and function recovery. Herein, a three-dimensional (3D) sponge-filled nanofibrous NGC (sf@NGC) resembling the structure of native peripheral nerves was developed. The conduit was fabricated by electrospinning a poly(L-lactide-co-glycolide) (PLGA) membrane, whereas the intraluminal filler was obtained by freeze-drying a collagen-based matrix (ColM) resembling the extracellular matrix. The effects of the electrospinning process and of the composition of ColM on the physicochemical performance of sf@NGC were investigated in detail. Furthermore, the biocompatibility of the PLGA sheath and ColM were evaluated. The continuous and homogeneous PLGA nanofiber membrane had high porosity and tensile strength. ColM was shown to exhibit an ECM-like architecture characterized by a multistage pore structure and a high porosity level of over 70%. The PLGA sheath and ColM were shown to possess stagewise degradability and good biocompatibility. In conclusion, sf@NGC may have a favorable potential for the treatment of nerve reconstruction.


Assuntos
Regeneração Tecidual Guiada , Nanofibras , Nervo Isquiático , Nanofibras/química , Regeneração Tecidual Guiada/métodos , Colágeno/farmacologia , Alicerces Teciduais/química , Regeneração Nervosa
9.
Chemosphere ; 343: 140237, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37734501

RESUMO

Spinosad is a highly effective macrolide insecticide with a wide range of applications. However, few studies have been reported on the effects of Spinosad on immune cells. The immune system is an important line of defense in the human body and plays an important role in maintaining the normal functioning of the organism. Meanwhile, macrophages, neutrophils and Thymic T cells are an important component of the immune system. We studied the immunotoxicity of Spinosad using zebrafish and THP-1 cells. In vivo, Spinosad (0-20 µM) did not cause developmental toxicity in zebrafish, but induced damage to immune cells. In vitro, Spinosad (0-20 µM) inhibited THP-1 cells viability and induced mitochondrial damage and oxidative stress production. In further studies, it impaired phagocytosis of THP-1 cells and interfered with lipid metabolism. In addition, we found that Spinosad can promote the formation of the inflammatory body NLRP3 (NLR family, pyrin domain-containing 3) and activate the NF-kappa B (NF-κB) signaling pathway. These results suggest that Spinosad has a potential risk for inducing immunotoxicity. This study has drawn attention to Spinosad-induced immunotoxicity.

10.
Inorg Chem ; 62(38): 15641-15650, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37690055

RESUMO

When it comes to an efficient catalytic oxygen evolution reaction (OER) in the production of renewable energy and chemicals, the construction of heterogeneous structures is crucial to break the linear scalar relationship of a single catalyst. This heterogeneous structure construction helps creatively achieve high activity and stability. However, the synthesis process of heterogeneous crystalline materials is often complex and challenging to capture and reproduce, which limits their application. Here, the dynamic process of structural changes in Co-MOFs in alkali was captured by in situ powder X-ray diffraction, FT-IR spectroscopy, and Raman spectroscopy, and several self-reconfigured MOF heterogeneous materials with different structures were stably isolated. The created ß-Co(OH)2/Co-MOF heterojunction structure facilitates rapid mass-charge transfer and exposure of active sites, which significantly enhanced OER activity. Experimental results show that this heterogeneous structure achieves a low overpotential of 333 mV at 10 mA cm-2. The findings provide new insights and directions for the search for highly reactive cobalt-based MOFs for sustainable energy technologies.

11.
Nanoscale ; 15(34): 14249-14256, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37602367

RESUMO

All fluorescence white organic light-emitting diodes (WOLEDs) based on thermally activated delayed fluorescence (TADF) emitters are an attractive route to realize highly efficient and high color quality white light sources. However, harvesting triplet excitons in these devices remains a formidable challenge, particularly for WOLEDs involving conventional fluorescent emitters. Herein, we report a universal design strategy based on a co-host system and a cascaded exciton transfer configuration. The co-host system furnishes a broad and charge-balanced exciton generation zone, which simultaneously endows the devices with low efficiency roll-off and good color stability. A yellow TADF layer is put forward as an intermediate sensitizer layer between the blue TADF light-emitting layer (EML) and the red fluorescence EML, which not only constructs an efficient cascaded Förster energy transfer route but also blocks the triplet exciton loss channel through Dexter energy transfer. With the proposed design strategy, three-color all fluorescence WOLEDs reach a maximum external quantum efficiency (EQE) of 22.4% with a remarkable color rendering index (CRI) of 92 and CIE coordinates of (0.37, 0.40). Detailed optical simulation confirms the high exciton utilization efficiency. Finally, by introducing an efficient blue emitter 5Cz-TRZ, a maximum EQE of 30.1% is achieved with CIE coordinates of (0.42, 0.42) and a CRI of 84 at 1000 cd m-2. These outstanding results demonstrate the great potential of all fluorescence WOLEDs in solid-state lighting and display panels.

13.
Org Lett ; 25(31): 5790-5794, 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37523673

RESUMO

A chiral aldehyde/palladium catalysis-enabled asymmetric α-allylation of NH2-unprotected amino acid esters with 1,3-disubstituted allyl acetates is described in this work. With the utilization of different chiral phosphine ligands, both the anti- and syn-selective allylation reactions are achieved enantioselectively. A series of α,α-disubstituted amino acid esters bearing two adjacent chiral centers are produced in moderate-to-excellent yields, diastereoselectivities, and enantioselectivities.

14.
Chem Sci ; 14(21): 5665-5671, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37265737

RESUMO

The direct catalytic α-hydrocarbylation of readily available amino acids with halohydrocarbons is one of the most straightforward methods leading to α,α-disubstituted non-proteinogenic α-amino acid compounds. However, all the reported methodologies depend on N-protected amino acids as starting materials. Herein, we report on three highly efficient aldehyde-catalyzed direct α-hydrocarbylations of N-unprotected amino acid esters with aryl-, allyl-, and benzyl halides. By promoting a simple chiral BINOL-aldehyde catalyst or combining catalysts of a chiral aldehyde and Lewis acid ZnCl2, the asymmetric α-arylation, α-allylation, and α-benzylation of amino acid esters with the corresponding halohydrocarbons proceed smoothly, producing α,α-disubstituted α-amino acids in moderate-to-high yields and good-to-excellent enantioselectivities. The asymmetric α-arylation reaction can be applied in the formal synthesis of the clinical candidate compound (+)-AG-041R. Based on the results given by control experiments, three reaction models are proposed to illustrate the stereoselective-control outcomes.

15.
J Pain Res ; 16: 1127-1136, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37025954

RESUMO

Purpose: A single-injection nerve block provides excellent analgesia in a short time, but rebound pain after the nerve block disappears has attracted researchers' attention. The aim of this study is to evaluate the effect of intravenous dexamethasone on rebound pain after adductor canal block (ACB) and popliteal sciatic nerve block in patients with ankle fracture. Methods: We recruited 130 patients with ankle fractures scheduled for open reduction and internal fixation (ORIF), each of whom received ACB and popliteal sciatic nerve block. Patients were divided into two groups: C (ropivacaine only) and IV (ropivacaine with intravenous dexamethasone). The primary outcome was the incidence of rebound pain. Secondary outcomes included the following: pain scores at 6 h (T1), 12 h (T2), 18 h (T3), 24 h (T4), and 48 h (T5) after operation; duration of the nerve block; number of presses of the analgesia pump and rescue analgesic consumption in the three-day postoperative period; quality of recovery scale (QoR-15 score); postoperative sleep quality; satisfaction of patients; and levels of serum inflammatory markers (IL-1ß, IL-6, and TNF-α) six hours after surgery. Results: Compared with group C, the incidence of rebound pain in group IV was significantly reduced, and the duration of nerve block was extended by approximately nine hours (P<0.05). Moreover, patients in group IV had significantly lower pain scores at T2-T4, lower levels of serum inflammatory markers (IL-1ß, IL-6, and TNF-α), higher QoR-15 score two days after the operation, and satisfactory sleep quality the night after surgery (P<0.05). Conclusion: Intravenous dexamethasone can reduce the rebound pain after adductor block and sciatic popliteal nerve block in patients with ankle fracture surgery, prolong the duration of nerve block, and improve the quality of early postoperative recovery.

16.
Altern Ther Health Med ; 29(5): 97-101, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37023309

RESUMO

Background: Femoral neck fracture is acknowledged as one of the common injuries in clinical orthopedics. Our study was aimed at investigating the efficacy of femoral neck fixation vs the KHS dynamic compression locking plate system in the treatment of femoral neck fracture. Methods: This was a prospective study. A toteal of 90 patients with femoral neck fracture who were admitted to The Third Hospital of Hebei Medical University in Shijiazhuang, China from August 2017 to March 2020 were enrolled in our study. The patients were randomly divided into the control group (45 patients allocated to intervention with the novel femoral neck dynamic compression locking plate system) and the study group (45 patients who underwent femoral neck system fixation). Intraoperative blood loss, surgery duration, fracture healing time and related complications in the 2 groups were monitored and evaluated. The recovery of hip joint function at different times in the 2 groups were closely monitored. Results: The 2 groups completed the surgery process, and the incision healed. All patients were followed up for 6 to 8 months, with an average follow-up time of 7.01 ± 0.21 months. Surgery duration, length of hospital stay and fracture healing time in the study group were significantly lower than in the control group (P < .05), while no significant difference was found in intraoperative blood loss between the 2 groups (P > .05). At 1 and 3 months after surgery, hip joint function in the study group was significantly higher than in the control group (P < .05), but 6 months after surgery, there was no significant difference between the 2 groups (P > .05). There were no complications in the study group, whereas 1 patient had a complication in the control group. The total incidence of complications in the study group was lower than in the control group, but the difference was not significant (P > .05). Conclusion: Femoral neck system fixation demonstrated superior efficacy to the KHS femoral neck dynamic compression locking plate system in femoral neck fracture, and is considered as a valid method for wide application.


Assuntos
Fraturas do Colo Femoral , Fixação Interna de Fraturas , Humanos , Fixação Interna de Fraturas/métodos , Colo do Fêmur , Perda Sanguínea Cirúrgica , Estudos Prospectivos , Estudos Retrospectivos , Fraturas do Colo Femoral/cirurgia , Resultado do Tratamento
17.
Environ Sci Pollut Res Int ; 30(19): 54616-54627, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36881236

RESUMO

The preparation of carbon dots (CDs) from waste fish scales is an attractive and high-value transformation. In this study, fish scales were used as a precursor to prepare CDs, and the effects of hydrothermal and microwave methods on their fluorescence properties and structures were evaluated. The microwave method was more conducive to the self-doping of nitrogen due to rapid and uniform heating. However, the low temperature associated with the microwave method resulted in insufficient dissolution of the organic matter in the fish scales, resulting in incomplete dehydration and condensation and the formation of nanosheet-like CDs, whose emission behavior had no significant correlation with excitation. Although the CDs prepared using the conventional hydrothermal method showed lower nitrogen doping, the relative pyrrolic nitrogen content was higher, which was beneficial in improving their quantum yield. Additionally, the controllable high temperature and sealed environment used in the conventional hydrothermal method promoted dehydration and condensation of the organic matter in the fish scales to form CDs with a higher degree of carbonization, uniform size, and higher C = O/COOH content. CDs prepared using the conventional hydrothermal method exhibited higher quantum yields and excitation wavelength-dependent emission behavior.


Assuntos
Carbono , Pontos Quânticos , Animais , Carbono/química , Micro-Ondas , Desidratação , Pontos Quânticos/química , Nitrogênio/química
18.
Biol Trace Elem Res ; 201(12): 5756-5763, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36862247

RESUMO

This study aimed to investigate the effects of selenium (Se)-enriched Bacillus subtilis (Se-BS) on growth performance, antioxidant capacity, immune status, and gut health in broilers. A total of 240 one-day-old Arbor Acres broilers were randomly allotted to four groups and fed with basal diet (control group), 0.30 mg/kg Se (SS group), 3 × 109 CFU/g B. subtilis (BS group), and 0.30 mg/kg Se + 3 × 109 CFU/g B. subtilis (Se-BS group) for 42 days. The results showed that Se-BS supplementation increased body weight (BW), average daily gain, the activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), and peroxidase (POD), total antioxidant capacity (T-AOC), and the contents of interleukin (IL)-2, IL-4, and immunoglobulin (Ig) G in plasma, the index and wall thickness of the duodenum, the villus height and crypt depth of the jejunum, and GPx-1 and thioredoxin reductase 1 mRNA levels in liver and intestine and decreased feed conversion ratio (FCR) and plasma malondialdehyde (MDA) content compared with the control group on day 42 (P < 0.05). Compared with groups SS and BS, Se-BS supplementation increased BW, the activities of GPx, CAT, and POD, and the contents of IL-2, IL-4, and IgG in plasma, the index and wall thickness of the duodenum, the crypt depth and secretory IgA content of the jejunum, and GPx-1 mRNA levels in liver and intestine and decreased FCR and plasma MDA content on day 42 (P < 0.05). In conclusion, Se-BS supplementation effectively improved the growth performance antioxidant capacity, immune status, and gut health of broilers.


Assuntos
Antioxidantes , Selênio , Animais , Selênio/farmacologia , Galinhas , Bacillus subtilis , Suplementos Nutricionais , Interleucina-4 , Dieta/veterinária , Glutationa Peroxidase , RNA Mensageiro/genética , Ração Animal/análise
19.
Anal Chim Acta ; 1247: 340900, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36781253

RESUMO

The unique triple helix structure of collagen plays an important role in its biological properties, and the triple helix integrity is closely correlated with its molecular behavior and biological functions. Nevertheless, there is still a lack of convenient, accurate and practical methods for quantitatively determining collagen triple helix integrity. Herein, we first prepared bovine skin collagen peptide (BSCP)-protected Au/Ag nanoclusters (Au/AgNCs@BSCP) with excellent optical properties, high stability and good biocompatibility, which could adsorb on WS2 surface leading to fluorescence quenching. Upon the addition of collagen, the interaction of collagen and Au/AgNCs@BSCP led to the detachment of Au/AgNCs@BSCP from the WS2 surface, causing an increase in the fluorescence signal. Using the difference in the fluorescence recovery of the different samples, we achieved the quantitative determination of collagen triple helix integrity. This developed strategy exhibited excellent accuracy, selectivity, and practicality, thus showing promising potentials in biomedical applications.


Assuntos
Ouro , Nanopartículas Metálicas , Animais , Bovinos , Ouro/química , Nanopartículas Metálicas/química , Prata/química , Espectrometria de Fluorescência/métodos , Peptídeos , Corantes
20.
Cell Death Discov ; 9(1): 42, 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36732504

RESUMO

Resistance to radiotherapy remains a major unmet clinical obstacle in the treatment of locally advanced rectal cancer. Cancer stem cells (CSCs) are considered to mediate tumor development and radioresistance. However, the role of CSCs in regulating resistance to radiotherapy in colorectal cancer (CRC) remains largely unknown. We established two radioresistant CRC cell lines, HCT116-R and RKO-R, using fractionated irradiation. Analysis using miRNA sequencing and quantitative real-time PCR confirmed lower levels of miR-7-5p in both of the radioresistant cells compared to their parental cells. Subsequently, we validated that miR-7-5p expression was decreased in cancerous tissues from radiotherapy-resistant rectal cancer patients. The Cancer Genome Atlas (TCGA) database analyses revealed that low miR-7-5p expression was significantly correlated with poor prognosis in CRC patients. Overexpression of miR-7-5p led to a rescue of radioresistance and an increase in radiation-induced apoptosis, and attenuated the stem cell-like properties in HCT116-R and RKO-R cells. Conversely, knocking down miR-7-5p in parental HCT116 and RKO cells suppressed the sensitivity to radiation treatment and enhance cancer cell stemness. Stemness-associated transcription factor KLF4 was demonstrated as a target of miR-7-5p. Rescue experiments revealed that miR-7-5p/KLF4 axis could induce radiosensitivity by regulating CSCs in colorectal cancer cells. Furthermore, we used CRC tumor tissues which exhibited resistance to neoadjuvant radiotherapy to establish a patient-derived xenograft (PDX) mouse model. Tail vein injection of magnetic nanoparticles carrying miR-7-5p mimics into the PDX mice significantly inhibited tumor growth with or without irradiation treatment in vivo. Our current studies not only demonstrate an anti-cancer function of miR-7-5p in regulating CSC properties and radiosensitivity in colorectal cancer, but also provide a novel potential strategy for delaying or reverse radiation resistance in preoperative radiotherapy of CRC patients.

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