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1.
Front Bioeng Biotechnol ; 12: 1401899, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38994122

RESUMO

Background: The bone repair requires the bone scaffolds to meet various mechanical and biological requirements, which makes the design of bone scaffolds a challenging problem. Novel triply periodic minimal surface (TPMS)-based bone scaffolds were designed in this study to improve the mechanical and biological performances simultaneously. Methods: The novel bone scaffolds were designed by adding optimization-guided multi-functional pores to the original scaffolds, and finite element (FE) method was used to evaluate the performances of the novel scaffolds. In addition, the novel scaffolds were fabricated by additive manufacturing (AM) and mechanical experiments were performed to evaluate the performances. Results: The FE results demonstrated the improvement in performance: the elastic modulus reduced from 5.01 GPa (original scaffold) to 2.30 GPa (novel designed scaffold), resulting in lower stress shielding; the permeability increased from 8.58 × 10-9 m2 (original scaffold) to 5.14 × 10-8 m2 (novel designed scaffold), resulting in higher mass transport capacity. Conclusion: In summary, the novel TPMS scaffolds with multi-functional pores simultaneously improve the mechanical and biological performances, making them ideal candidates for bone repair. Furthermore, the novel scaffolds expanded the design domain of TPMS-based bone scaffolds, providing a promising new method for the design of high-performance bone scaffolds.

2.
World J Gastroenterol ; 30(22): 2893-2901, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38947295

RESUMO

BACKGROUND: This study employed a phenomenological research approach within qualitative research to explore the challenges encountered by elderly individuals with temporary colostomies in managing their daily lives and care needs. Protecting the anus surgery combined with temporary colostomy has emerged as a prevalent treatment modality for low rectal cancer. However, the ileostomy is susceptible to peri-stoma skin complications, as well as fluid, electrolyte, and nutritional imbalances, posing challenges to effective management. The successful self-management of patients is intricately linked to their adjustment to temporary colostomy; nonetheless, there remains a dearth of research examining the factors influencing self-care among temporary colostomy patients and the obstacles they confront. AIM: To investigate the lived experiences, perceptions, and care requirements of temporary colostomy patients within their home environment, with the ultimate goal of formulating a standardized management protocol. METHODS: Over the period of June to August 2023, a purposive sampling technique was utilized to select 12 patients with temporary intestinal stomas from a tertiary hospital in Shanghai, China. Employing a phenomenological research approach, a semi-structured interview guide was developed, and qualitative interviews were conducted using in-depth interview techniques. The acquired data underwent coding, analysis, organization, and summarization following Colaizzi's seven-step method. RESULTS: The findings of this study revealed that the experiences and needs of patients with temporary intestinal stomas can be delineated into four principal themes: Firstly, Temporary colostomy patients bear various burdens and concerns about the uncertainty of disease progression; secondly, patients exhibit limited self-care capabilities and face information deficits, resulting in heightened reliance on healthcare professionals; thirdly, patients demonstrate the potential for internal motivation through proactive self-adjustment; and finally, patients express a significant need for emotional and social support. CONCLUSION: Home-living patients with temporary intestinal stomas confront multifaceted challenges encompassing burdens, inadequate self-care abilities, informational deficits, and emotional needs. Identifying factors influencing patients' self-care at home and proposing strategies to mitigate barriers can serve as a foundational framework for developing and implementing nursing interventions tailored to the needs of patients with temporary intestinal stomas.


Assuntos
Colostomia , Pesquisa Qualitativa , Autocuidado , Humanos , Feminino , Idoso , Masculino , Colostomia/psicologia , China/epidemiologia , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Ileostomia/psicologia , Ileostomia/efeitos adversos , Qualidade de Vida , Entrevistas como Assunto , Neoplasias Retais/psicologia , Neoplasias Retais/cirurgia , Neoplasias Retais/terapia , Neoplasias Retais/patologia , Adaptação Psicológica
3.
J Asian Nat Prod Res ; : 1-8, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38973288

RESUMO

Two new cucurbitane-type triterpenoid saponins, 2,20ß,22ß-trihydroxy-16α,23(R)-epoxycucurbita-1,5,24-triene-3,11-dione 2-O-ß-D-glucopyranoside (1), 2,20ß,22α-trihydroxy-16α,23(S)-epoxycucurbita-1,5,11,24-tetraene-3-one 2-O-ß-D-glucopyranoside (2) were isolated from the fruit of Citrullus colocynthis (L.) Schrad. Their structures were elucidated by mass spectrometry, IR, 1D, and 2D NMR spectroscopy, etc. Besides, both of the compounds showed significant hepatoprotective activities at 10 µM against paracetamol-induced HepG2 cell damage.

4.
Vox Sang ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38970298

RESUMO

BACKGROUND AND OBJECTIVES: To investigate the prevalence, genotype and haematological characteristics of glucose-6-phosphate dehydrogenase (G6PD) deficiency in the blood donor population of Wuxi area (Jiangsu Province, China) and to assess the impact of their red blood cell (RBC) units on clinical transfusion. MATERIALS AND METHODS: We conducted genotyping and large-scale screening for G6PD enzyme activity in the blood donors of Wuxi City. In addition, we assessed the haematological parameters of G6PD-deficient and non-deficient blood donors, and investigated the adverse transfusion reactions in patients transfused with G6PD-deficient blood. RESULTS: We investigated 17,113 blood donors, among whom 44 (0.26%) were tested positive for G6PD deficiency. We identified 40 G6PD gene variants, among which c.1388G>A, c.1376G>T, c.1024C>T and c.95A>G were common. In addition, we identified two novel G6PD gene variants, c.1312G>A and c.1316G>A. The G6PD-deficient and non-deficient blood samples showed a significant difference in the RBC, mean corpuscular volume (MCV), mean corpuscular Hb (MCH), RBC distribution width, total bilirubin (TBIL), direct bilirubin (DBIL) and indirect bilirubin (IBIL) values. However, the two samples showed no significant difference in the haemolysis rate at the end of the storage period. Finally, transfusion with G6PD-deficient RBC units did not lead to any adverse transfusion reactions. CONCLUSION: The positive rate of G6PD deficiency in the blood donor population of Wuxi City is 0.26%, and the genetic variants identified in this population are consistent with the common genetic variants observed in the Chinese population. Blood centres can establish a database on G6PD-deficient blood donors and mark their RBC units to avoid their use for special clinical patients.

6.
Enzyme Microb Technol ; 179: 110464, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38850682

RESUMO

Dunaliella salina is an innovative expression system due to its distinct advantages such as high salt tolerance, low susceptibility to contamination, and the absence of the cell wall. While nuclear transformation has been extensively studied, research on D. salina chloroplast transformation remains in the preliminary stages. In this study, we established an efficient chloroplast expression system for D. salina using Golden Gate assembly. We developed a D. salina toolkit comprising essential components such as chloroplast-specific promoters, terminators, homologous fragments, and various vectors. We confirmed its functionality by expressing the EGFP protein. Moreover, we detailed the methodology of the entire construction process. This expression system enables the specific targeting of foreign genes through simple homologous recombination, resulting in stable expression in chloroplasts. The toolkit achieved a relatively high transformation efficiency within a shorter experimental cycle. Consequently, the construction and utilization of this toolkit have the potential to enhance the efficiency of transgenic engineering in D. salina and advance the development of microalgal biofactories.

8.
Laryngoscope Investig Otolaryngol ; 9(3): e1275, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38835331

RESUMO

Objectives: The objective of this study is to summarize the clinical characteristics, treatment, and prognosis of parotid tumors in children and adolescents. Methods: Fifty-three children and adolescents diagnosed with parotid gland tumors were included. Survival was evaluated using the Kaplan-Meier method. Log-rank test and multivariate analysis were used to analyze the association between clinical factors and recurrence. Results: Of the 53 patients, 30 cases were benign and 23 cases were malignant. All patients underwent surgery. Patients with malignant tumors with high-risk factors received radiotherapy or chemotherapy. The median follow-up time was 61 months. Of these, 1 patient with benign tumor and 5 patients with malignant tumors recurred. Of the patients with malignant tumors, 2 developed distant metastases and 2 died. The 5-year overall survival (OS) and 5-year locoregional recurrence-free survival (LRFS) rates for benign tumors were 100.0% and 92.9%, respectively, whereas the 5-year OS and 5-year LRFS rates for malignant tumors were 94.4% and 72.5%, respectively. The log-rank univariate test showed that tumor size >3.5 cm (p = .056), distant metastasis (p = .056), and stage III and IV (p = .032) were associated with recurrence. However, multivariate analysis did not show the above factors to be independent prognostic factors for LRFS. Conclusion: Surgery for benign tumors depends on the location and size. Surgery for malignant parotid tumors depends mainly on the stage, grade, pathological type, and recurrence. Prophylactic lymph node dissection is required for high-grade tumors. Radiotherapy or chemotherapy for children needs more research. Both benign and malignant tumors have high survival rates after active treatment. Level of evidence: Level 2.

9.
Int J Biol Macromol ; : 133025, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38852737

RESUMO

The Rosa cymosa Tratt, an herbal plant from the Rosaceae family, has historically been valued in China for its medicinal and edible properties. In this study, a novel polysaccharide from R. cymosa fruit, termed PRCP (purified R. cymosa polysaccharide), was isolated using water extraction, decolorization, deproteinization, and ion-exchange chromatography. The structural characteristics of PRCP were investigated using monosaccharide composition analysis, methylation, GPC, FTIR, CD, and NMR spectroscopy. The immunomodulatory effect and potential mechanism of PRCP were evaluated in vitro using a macrophage cell model. Results indicated that PRCP (37.28 kDa) is a highly branched polysaccharide (72.61 %) primarily composed of arabinogalactan, rhamnogalacturonan, and galactoglucan domains with 13 types of glycosidic linkage fragments. Furthermore, PRCP appears to modulate immunomodulatory effects by influencing the phosphorylation of P38 and JNK proteins in the MAPK pathway. Collectively, these findings highlight the potential of PRCP as a promising natural functional food ingredient for immunostimulation.

10.
J Am Chem Soc ; 146(23): 15815-15824, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38832857

RESUMO

Ribonuclease targeting chimera (RIBOTAC) represents an emerging strategy for targeted therapy. However, RIBOTAC that is selectively activated by bio-orthogonal or cell-specific triggers has not been explored. We developed a strategy of inducible RIBOTAC (iRIBOTAC) that enables on-demand degradation of G-quadruplex (G4) RNAs for precision cancer therapy. iRIBOTAC is designed by coupling an RNA G4 binder with a caged ribonuclease recruiter, which can be decaged by a bio-orthogonal reaction, tumor-specific enzyme, or metabolite. A bivalent G4 binder is engineered by conjugating a near-infrared (NIR) fluorescence G4 ligand to a noncompetitive G4 ligand, conferring fluorescence activation on binding G4s with synergistically enhanced affinity. iRIBOTAC is demonstrated to greatly knockdown G4 RNAs upon activation under bio-orthogonal or cell-specific stimulus, with dysregulation of gene expressions involving cell killing, channel regulator activity, and metabolism as revealed by RNA sequencing. This strategy also shows a crucial effect on cell fate with remarkable biochemical hallmarks of apoptosis. Mice model studies demonstrate that iRIBOTAC allows selective imaging and growth suppression of tumors with bio-orthogonal and tumor-specific controls, highlighting G4 RNA targeting and inducible silencing as a valuable RIBOTAC paradigm for cancer therapy.


Assuntos
Quadruplex G , RNA Mensageiro , Ribonucleases , Humanos , Animais , Camundongos , Ribonucleases/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Inativação Gênica , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico , Neoplasias/terapia , Neoplasias/genética
11.
Nat Prod Res ; : 1-8, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916532

RESUMO

Two new polycyclic polyprenylated acylphloroglucinols, hyperguanyes A and B (1-2) together with eight known compounds (3-10), were isolated from Hypericum perforatum L. Their structures were determined by using comprehensive spectroscopic techniques and quantum chemical calculation. The in vitro anti-cholinesterase activity of all compounds were studied. Among them, compounds 1-4, 8 and 9 exhibited anti-AchE and anti-BchE effects with IC50 ranging from 0.34 ± 0.04 to 15.68 ± 0.54 µM.

12.
PeerJ ; 12: e17561, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38915383

RESUMO

Background: To evaluate the efficacy and safety of Brolucizumab for neovascular age-related macular degeneration (n-AMD) through a systematic review and meta-analysis. Materials and Methods: Cochrane, PubMed, Embase, and Web of Science databases were comprehensively searched for relevant studies. Stata and RevMan5.4 were applied for meta-analysis and risk of bias assessment. Data on the best-corrected visual acuity (BCVA), central subfield thickness (CSFT), presence of intraretinal fluid (IRF) and/or subretinal fluid (SRF), participants with ≥1 serious adverse events, and participants with ≥1 adverse events were analyzed. Results: Six studies were finally included. Meta-analysis showed statistical differences in BCVA [SMD = -0.65, 95% CI [-0.17 to -0.23], P < 0.05], the presence of IRF and/or SRF [RR = 0.67, 95% CI [0.56-0.79], P < 0.05], and the safety of participants with ≥1 serious adverse events [RR = 0.57, 95% CI [0.39-0.84], P < 0.05] between the experimental group and the control group. However, no statistical differences were observed in CSFT [SMD = -1.16, 95% CI [-2.79 to 0.47], P > 0.05] or the safety of participants with ≥1 adverse events [RR = 1.07, 95% CI [0.97-1.17], P > 0.05]. Conclusions: Compared to other anti-VEGF drugs such as Aflibercept and Ranibizumab, intravitreal injection of 6 mg Brolucizumab is more effective and safer for n-AMD, especially in the presence of IRF and/or SRF, and for participants with ≥1 serious adverse events.


Assuntos
Inibidores da Angiogênese , Anticorpos Monoclonais Humanizados , Degeneração Macular , Humanos , Inibidores da Angiogênese/efeitos adversos , Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Injeções Intravítreas , Degeneração Macular/tratamento farmacológico , Resultado do Tratamento , Acuidade Visual/efeitos dos fármacos , Degeneração Macular Exsudativa/tratamento farmacológico
13.
Diagnostics (Basel) ; 14(12)2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38928638

RESUMO

Carotid blowout syndrome (CBS) is a rare yet life-threatening complication that occurs after radiation therapy (RT). This study aimed to determine the incidence of CBS in patients with head and neck cancer (HNC) undergoing contemporary RT and to explore potential discrepancies in the risk of CBS between nasopharyngeal cancer (NPC) and non-NPC patients. A total of 1084 patients with HNC who underwent RT between 2013 and 2023 were included in the study. All patients were under regular follow-ups at the radio-oncology department, and underwent annual contrast-enhanced computed tomography and/or magnetic resonance imaging for cancer recurrence surveillance. Experienced neuroradiologists and vascular neurologists reviewed the recruited patients' images. Patients were further referred to the neurology department for radiation vasculopathy evaluation. The primary outcome of this study was CBS. Patients were categorized into NPC and non-NPC groups and survival analysis was employed to compare the CBS risk between the two groups. A review of the literature on CBS incidence was also conducted. Among the enrolled patients, the incidence of CBS in the HNC, NPC, and non-NPC groups was 0.8%, 0.9%, and 0.7%, respectively. Kaplan-Meier analysis revealed no significant difference between the NPC and non-NPC groups (p = 0.34). Combining the findings for our cohort with those of previous studies revealed that the cumulative incidence of CBS in patients with HNC is 5% (95% CI = 3-7%) after both surgery and RT, 4% (95% CI = 2-6%) after surgery alone, and 5% (95% CI = 3-7%) after RT alone. Our findings indicate a low incidence of CBS in patients with HNC undergoing contemporary RT. Patients with NPC may have a CBS risk close to that of non-NPC patients. However, the low incidence of CBS could be a potentially cause of selection bias and underestimation bias.

15.
Acta Pharm Sin B ; 14(6): 2567-2580, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38828157

RESUMO

The pandemic of SARS-CoV-2 worldwide with successive emerging variants urgently calls for small-molecule oral drugs with broad-spectrum antiviral activity. Here, we show that carrimycin, a new macrolide antibiotic in the clinic and an antiviral candidate for SARS-CoV-2 in phase III trials, decreases the efficiency of programmed -1 ribosomal frameshifting of coronaviruses and thus impedes viral replication in a broad-spectrum fashion. Carrimycin binds directly to the coronaviral frameshift-stimulatory element (FSE) RNA pseudoknot, interrupting the viral protein translation switch from ORF1a to ORF1b and thereby reducing the level of the core components of the viral replication and transcription complexes. Combined carrimycin with known viral replicase inhibitors yielded a synergistic inhibitory effect on coronaviruses. Because the FSE mechanism is essential in all coronaviruses, carrimycin could be a new broad-spectrum antiviral drug for human coronaviruses by directly targeting the conserved coronaviral FSE RNA. This finding may open a new direction in antiviral drug discovery for coronavirus variants.

16.
Artigo em Inglês | MEDLINE | ID: mdl-38833104

RESUMO

PURPOSE: To comprehensively investigate the diagnostic performance of routinely used assays in MPXV testing, the National Center of Clinical Laboratories in China conducted a nationwide external quality assessment (EQA) scheme and an evaluated nine assays used by ≥ 5 laboratories in the EQA. METHODS: MPXV virus-like particles with 2700, 900 and 300 copies/mL were distributed to 195 EQA laboratories. For extended analysis, triple-diluted samples from 9000 to 4.12 copies/mL were repeated 20 times using the assays employed by ≥ 5 laboratories. The diagnostic performance was assessed by analyzing EQA data and calculating the limits of detection (LODs). RESULTS: The performance was competent in 87.69% (171/195) of the participants and 87.94% (175/199) of the datasets. The positive percentage agreements (PPAs) were greater than 99% for samples at 2700 and 900 copies/mL, and 95.60% (761/796) for samples at 300 copies/mL. The calculated LODs for the two clades ranged from 228.44 to 924.31 copies/mL and were greater than the LODs specified by the respective kits. EasyDiagnosis had the lowest calculated LODs and showed superior performance in EQA, whereas BioGerm and Sansure, with higher calculated LODs, did not perform well in EQA. CONCLUSION: This study provides valuable information from the EQA data and evaluation of the diagnostic performance of MPXV detection assays. It also provided insights into reagent optimization and enabled prompt public health interventions for the outbreak.

18.
Science ; 384(6701): 1254-1259, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38870285

RESUMO

Low-dimensional water transport can be drastically enhanced under atomic-scale confinement. However, its microscopic origin is still under debate. In this work, we directly imaged the atomic structure and transport of two-dimensional water islands on graphene and hexagonal boron nitride surfaces using qPlus-based atomic force microscopy. The lattice of the water island was incommensurate with the graphene surface but commensurate with the boron nitride surface owing to different surface electrostatics. The area-normalized static friction on the graphene diminished as the island area was increased by a power of ~-0.58, suggesting superlubricity behavior. By contrast, the friction on the boron nitride appeared insensitive to the area. Molecular dynamic simulations further showed that the friction coefficient of the water islands on the graphene could reduce to <0.01.

19.
J Asian Nat Prod Res ; : 1-6, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38860491

RESUMO

Three new flavonoids including two isoflavanones sophortones A and B (1 and 2), and one chalcone sophortone C (3) were isolated from the roots of Sophora tonkinensis. Their structures were established by UV, IR, HRESIMS, and NMR data. The absolute configurations of 1 and 2 were determined by electronic circular dichroism (ECD) calculations.

20.
Nat Commun ; 15(1): 3854, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719830

RESUMO

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

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