RESUMO
Bacterial membrane vesicles (BMVs) are crucial biological vehicles for facilitating interspecies and interkingdom interactions. However, the extent and mechanisms of BMV involvement in bacterial-algal communication remain elusive. This study provides evidence of BMVs delivering cargos to targeted microalgae. Membrane vesicles (MVs) from Chitinimonas prasina LY03 demonstrated an algicidal profile similar to strain LY03. Further investigation revealed Tambjamine LY2, an effective algicidal compound, selectively packaged into LY03-MVs. Microscopic imaging demonstrated efficient delivery of Tambjamine LY2 to microalgae Heterosigma akashiwo and Thalassiosira pseudonana through membrane fusion. In addition, the study demonstrated the versatile cargo delivery capabilities of BMVs to algae, including the transfer of MV-carried nucleic acids into algal cells and the revival of growth in iron-depleted microalgae by MVs. Collectively, our findings reveal a previously unknown mechanism by which algicidal bacteria store hydrophobic algicidal compounds in MVs to trigger target microalgae death and highlight BMV potency in understanding and engineering bacterial-algae cross-talk.
Assuntos
Bactérias , Microalgas , Microalgas/metabolismo , Bactérias/metabolismo , Membrana Celular/metabolismo , Interações MicrobianasRESUMO
Electrocatalytic nitrate (NO3-) reduction to ammonia (NRA) offers a promising pathway for ammonia synthesis. The interfacial electronic interactions (IEIs) can regulate the physicochemical capabilities of catalysts in electrochemical applications, while the impact of IEIs on electrocatalytic NRA remains largely unexplored in current literature. In this study, the high-efficiency electrode Ag-modified Co3O4 (Ag1.5Co/CC) is prepared for NRA in neutral media, exhibiting an impressive nitrate conversion rate of 96.86%, ammonia Faradaic efficiency of 96.11%, and ammonia selectivity of ~100%. Notably, the intrinsic activity of Ag1.5Co/CC is ~81 times that of Ag nanoparticles (Ag/CC). Multiple characterizations and theoretical computations confirm the presence of IEIs between Ag and Co3O4, which stabilize the CoO6 octahedrons within Co3O4 and significantly promote the adsorption of reactants (NO3-) as well as intermediates (NO2- and NO), while suppressing the Heyrovsky step, thereby improving nitrate electroreduction efficiency. Furthermore, our findings reveal a synergistic effect between different active sites that enables tandem catalysis for NRA: NO3- reduction to NO2- predominantly occurs at Ag sites while NO2- tends to hydrogenate to ammonia at Co sites. This study offers valuable insights for the development of high-performance NRA electrocatalysts.
RESUMO
Photocatalysis has emerged as a extremely promising green technology for the treatment of uranium-containing wastewater. This study focuses on the fabrication of Ti3C2Tx/Cd0.8Zn0.2S composites with Schottky junctions through the in-situ growth of Cd0.8Zn0.2S on Ti3C2Tx nanosheets, enabling efficient photoreduction of U(VI) without the requirement of sacrificial agents. The results demonstrate that the Ti3C2Tx/Cd0.8Zn0.2S composites achieve remarkable 99.48 % U(VI) reduction efficiency within 60 min in a 100 ppm uranium solution. Furthermore, the removal rate remains above 90 % after five cycles. The formation of Schottky heterojunctions by Ti3C2Tx and Cd0.8Zn0.2S leads to the generation of an internal electric field that significantly promotes the rapid separation and transfer of photogenerated carriers, thereby enhancing the photocatalytic reduction efficiency of Ti3C2Tx/Cd0.8Zn0.2S-3:100 (TC/CZS-3:100). A considerable amount of electrons accumulate on Ti3C2Tx via the Schottky barrier, effectively facilitating the reduction of U(VI) to U(IV). As a co-catalyst, Ti3C2Tx enhances the photocatalytic performance and stability of Cd0.8Zn0.2S. Moreover, the practical application in the waste liquid of rare earth tailings reveals that the removal rate can be as high as 91.24 %. This research is of significant value in the development of effective photocatalysts for the elimination of uranium from wastewater.
RESUMO
Zinc (Zn)-based biodegradable metals (BMs) fabricated through conventional manufacturing methods exhibit adequate mechanical strength, moderate degradation behavior, acceptable biocompatibility, and bioactive functions. Consequently, they are recognized as a new generation of bioactive metals and show promise in several applications. However, conventional manufacturing processes face formidable limitations for the fabrication of customized implants, such as porous scaffolds for tissue engineering, which are future direction towards precise medicine. As a metal additive manufacturing technology, laser powder bed fusion (L-PBF) has the advantages of design freedom and formation precision by using fine powder particles to reliably fabricate metallic implants with customized structures according to patient-specific needs. The combination of Zn-based BMs and L-PBF has become a prominent research focus in the fields of biomaterials as well as biofabrication. Substantial progresses have been made in this interdisciplinary field recently. This work reviewed the current research status of Zn-based BMs manufactured by L-PBF, covering critical issues including powder particles, structure design, processing optimization, chemical compositions, surface modification, microstructure, mechanical properties, degradation behaviors, biocompatibility, and bioactive functions, and meanwhile clarified the influence mechanism of powder particle composition, structure design, and surface modification on the biodegradable performance of L-PBF Zn-based BM implants. Eventually, it was closed with the future perspectives of L-PBF of Zn-based BMs, putting forward based on state-of-the-art development and practical clinical needs.
RESUMO
Low adherence to hospital-based cardiac rehabilitation has been observed in patients after percutaneous coronary intervention. The effectiveness of home-based cardiac telerehabilitation in this setting is unclear. This study aimed to investigate the impact of home-based cardiac telerehabilitation on exercise endurance, disease burden status, cardiac function, and quality of life in patients after percutaneous coronary intervention. A total of 106 patients after percutaneous coronary intervention were randomly assigned to either the intervention group (receiving routine rehabilitation care and home-based cardiac telerehabilitation) or the control group (receiving routine care only), with 53 patients in each group. The 6-minute walking test, anerobic threshold, physical component summary score, mental component summary score, Vo2max, and left ventricular ejection fraction were measured in both groups before and 3 months after the intervention. Additionally, the Short-Form 12 scale and Family Burden Interview Schedule were used to assess quality of life and disease burden status. The intervention group demonstrated significant improvements in 6-minute walking test, anerobic threshold, Vo2max, physical component summary score, mental component summary score, Short-Form 12 scale, and Family Burden Interview Schedule scale scores compared with the control group (P<0.05). Results suggest that home-based cardiac telerehabilitation may improve exercise endurance and quality of life and reduce disease burden status in patients after percutaneous coronary intervention.
RESUMO
Outbreaks of short beak and dwarfism syndrome (SBDS), caused by a novel goose parvovirus (NGPV), have occurred in China since 2015. The NGPV, a single-stranded DNA virus, is thought to be vertically transmitted. However, the mechanism of NGPV immune evasion remains unclear. In this study, we investigated the impact of NGPV infection on the Cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway in duck embryonic fibroblast (DEF) cells. Our findings demonstrate that NGPV infection stimulates the mRNA expression of cGAS but results in weak IFN-ß induction. NGPV impedes the expression of IFN-ß and downstream interferon-stimulated genes, thereby reducing the secretion of IFN-ß induced by interferon-stimulating DNA (ISD) and poly (I: C). RNA-seq results show that NGPV infection downregulates interferon mRNA expression while enhancing the mRNA expression of inflammatory factors. Additionally, the results of viral protein over-expression indicate that VP1 exhibits a remarkable ability to inhibit IFN-ß expression compared to other viral proteins. Results indicated that only the intact VP1 protein could inhibit the expression of IFN-ß, while the truncated proteins VP1U and VP2 do not possess such characteristics. The immunoprecipitation experiment showed that both VP1 and VP2 could interact with IRF7 protein, while VP1U does not. In summary, our findings indicate that NGPV infection impairs the host's innate immune response by potentially modulating the expression and secretion of interferons and interferon-stimulating factors via IRF7 molecules, which are regulated by the VP1 protein.
RESUMO
Phellinus igniarius is a valuable medicinal and edible mushroom, and its polysaccharides exhibit excellent anti-inflammatory activity. During liquid fermentation to produce P. igniarius mycelia, the fermentation liquid is often discarded, but it contains extracellular polysaccharides. To better utilize these resources, P. igniarius SH-1 was fermented in a 100 L fermenter, and PIPS-2 was isolated and purified from the fermentation broth. The structural characteristics and anti-inflammatory activity of PIPS-2 were determined. PIPS-2 had a molecular weight of 22.855 kDa and was composed of galactose and mannose in a molar ratio of 0.38:0.62. Structural analysis revealed that the main chain of PIPS-2 involved â2)-α-D-Manp-(1 â 3)-ß-D-Galf-(1â, and the side chains involved α-D-Manp-(1 â 6)-α-D-Manp-(1â, α-D-Manp-(1 â 3)-α-D-Manp-(1â, and α-D-Manp-(1. PIPS-2 alleviated the symptoms of dextran sodium sulfate (DSS)-induced colitis in mice, improved the imbalance of inflammatory factors and antioxidant enzymes, and increased short-chain fatty acid contents. Combining the intestinal flora and metabolite results, PIPS-2 was found to regulate the abundance of Firmicutes, Lachnospiraceae_NK4A136_group, Proteobacteria, Bacteroides, and many serum metabolites including hexadecenal, copalic acid, 8-hydroxyeicosatetraenoic acid, artepillin C, and uric acid, thereby ameliorating metabolite related disorders in mice with colitis. In summary, PIPS-2 may improve colitis in mice by regulating the gut microbiota and metabolites.
Assuntos
Basidiomycota , Colite , Sulfato de Dextrana , Animais , Camundongos , Colite/induzido quimicamente , Colite/tratamento farmacológico , Basidiomycota/química , Polissacarídeos Fúngicos/química , Polissacarídeos Fúngicos/farmacologia , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Masculino , Polissacarídeos/química , Polissacarídeos/farmacologia , Peso Molecular , Modelos Animais de Doenças , Microbioma Gastrointestinal/efeitos dos fármacosRESUMO
Scarce and expensive iridium oxide is still the cornerstone catalyst of polymer-electrolyte membrane electrolyzers for green hydrogen production because of its exceptional stability under industrially relevant oxygen evolution reaction (OER) conditions. Earth-abundant transition metal oxides used for this task, however, show poor long-term stability. We demonstrate here the use of nitrogen-doped cobalt oxide as an effective iridium substitute. The catalyst exhibits a low overpotential of 240 mV at 10 mA cm-2 and negligible activity decay after 1000 h of operation in an alkaline electrolyte. Incorporation of nitrogen dopants not only triggers the OER mechanism switched from the traditional adsorbate evolution route to the lattice oxygen oxidation route but also achieves oxygen nonbonding (ONB) states as electron donors, thereby preventing structural destabilization. In a practical anion-exchange membrane water electrolyzer, this catalyst at anode delivers a current density of 1000 mA cm-2 at 1.78 V and an electrical efficiency of 47.8 kW-hours per kilogram hydrogen.
RESUMO
Ulcerative colitis (UC)-induced colitis-associated colorectal cancer (CAC) has a worse prognosis than sporadic colorectal cancer. And with the incidence of ulcerative colitis on the rise, it is critical to identify new therapeutic targets in time to stop the progression of inflammation to cancer. Through immunohistochemistry (IHC) and Gene Expression Omnibus (GEO) database analysis, we acquired the gene M2DEG, which is differentially expressed in M2 macrophages. The impact of M2DEG on the immune environment and clinical variables was confirmed through various data sets and actual tissue samples. Our findings indicate that patients with UC exhibiting reduced M2 macrophage infiltration tend to have more widespread disease, elevated endoscopic Mayo scores, and a higher probability of developing CAC. Through examining the string of M2DEG between UC and CAC, THBS2 emerged as a key marker. Elevated levels of THBS2 were notably linked to reduced overall survival (OS) and progression-free survival (RFS), and this heightened THBS2 expression played a crucial role in the spread of tumors, as verified by immunohistochemical studies. To sum up, patients with UC exhibiting reduced M2 macrophage infiltration have a higher propensity for CAC development, making THBS2 a crucial focus for converting UC into CAC. Furthermore, identifying antibody analogues targeting THBS2 could potentially lower the likelihood of CAC transformation in patients with UC.
Ulcerative colitis patients with low M2DEG expression have more extensive lesions, poorer immune responses, and higher Mayo endoscopic scores, implying a poorer prognosis and a greater likelihood of transformation from UC to CAC. THBS2 is M2DEG's core gene; the search for an antibody targeting THBS2 may help lower the risk of CAC transformation in patients with UC.
RESUMO
BACKGROUND: Clinical repair of critical-sized bone defects (CBDs) in the tibial diaphysis presents numerous challenges, including inadequate soft tissue coverage, limited blood supply, high load-bearing demands, and potential deformities. This study aimed to investigate the clinical feasibility and efficacy of employing 3D-printed prostheses for repairing CBDs exceeding 10 cm in the tibial diaphysis. METHODS: This retrospective study included 14 patients (11 males and 3 females) with an average age of 46.0 years. The etiologies of CBDs comprised chronic osteomyelitis (10 cases) and aseptic non-union (4 cases), with an average defect length of 16.9 cm. All patients underwent a two-stage surgical approach: (1) debridement, osteotomy, and cement spacer implantation; and (2) insertion of 3D-printed prostheses. The interval between the two stages ranged from 8 to 12 weeks, during which the 3D-printed prostheses and induced membranes were meticulously prepared. Subsequent to surgery, patients engaged in weight-bearing and functional exercises under specialized supervision. Follow-up assessments, including gross observation, imaging examinations, and administration of the Lower Extremity Functional Scale (LEFS), were conducted at 3, 6, and 12 months postoperatively, followed by annual evaluations thereafter. RESULTS: The mean postoperative follow-up duration was 28.4 months, with an average waiting period between prosthesis implantation and weight-bearing of 10.4 days. At the latest follow-up, all patients demonstrated autonomous ambulation without assistance, and their LEFS scores exhibited a significant improvement compared to preoperative values (30.7 vs. 53.1, P < 0.001). Imaging assessments revealed progressive bone regeneration at the defect site, with new bone formation extending along the prosthesis. Complications included interlocking screw breakage in two patients, interlocking screw loosening in one patient, and nail breakage in another. CONCLUSIONS: Utilization of 3D-printed prostheses facilitates prompt restoration of CBDs in the tibial diaphysis, enabling early initiation of weight-bearing activities and recovery of ambulatory function. This efficacious surgical approach holds promise for practical application.
Assuntos
Diáfises , Osteomielite , Impressão Tridimensional , Tíbia , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Osteomielite/cirurgia , Osteomielite/diagnóstico por imagem , Estudos Retrospectivos , Adulto , Tíbia/cirurgia , Tíbia/diagnóstico por imagem , Diáfises/cirurgia , Diáfises/diagnóstico por imagem , Fraturas não Consolidadas/cirurgia , Fraturas não Consolidadas/diagnóstico por imagem , Procedimentos de Cirurgia Plástica/métodos , Procedimentos de Cirurgia Plástica/instrumentação , Idoso , Seguimentos , Desenho de Prótese , Próteses e Implantes , Osteotomia/métodos , Suporte de Carga , Estudos de ViabilidadeRESUMO
Beta-gallium oxide (ß-Ga2O3) is emerging as a promising ultrawide band gap (UWBG) semiconductor, which is vital for high-power, high-frequency electronics and deep-UV optoelectronics. It is especially significant for flexible wearable electronics, enabling the fabrication of high-performance Ga2O3-based devices at low temperatures. However, the limited crystallinity and pronounced structural defects arising from the low-temperature deposition of Ga2O3 films significantly restrict the heterojunction interface quality and the relevant electrical performance of Ga2O3-based devices. In this work, cuprous oxide (Cu2O)/Zr-doped ß-Ga2O3 heterojunction diodes are fabricated by magnetron sputtering without intentional substrate heating, followed by an investigation into their microstructure and electrical behaviors. Zr doping can markedly enhance the Ga2O3 crystallinity at low substrate temperatures, transforming the amorphous structure of pristine Ga2O3 films into the crystallized ß phase. Moreover, crystalline ß-Ga2O3 facilitates the epitaxial growth of the Cu2O phase, suppressing the formation of detrimental secondary phase CuO at the heterojunction interface. Benefiting from the high-quality heterojunction interface, the Cu2O/Zr-doped ß-Ga2O3 heterojunction diode exhibits a near-ideal electrical behavior with a low ideality factor of 1.6. The consistent electrical parameters extracted from current-voltage (J-V) and capacitance-voltage (C-V) measurements also confirm the high quality of ß-Ga2O3. This work highlights the potential for the low-temperature production of high-quality ß-Ga2O3-based heterojunction devices through Zr doping.
RESUMO
In eukaryotes, the localization of small ribosomal subunits to mRNA transcripts requires the translation of Kozak elements at the starting site. The sequence of Kozak elements affects the translation efficiency of protein synthesis. However, whether the upstream nucleotide of Kozak sequence affects the expression of recombinant proteins in Chinese hamster ovary (CHO) cells remains unclear. In order to find the optimal sequence to enhance recombinant proteins expression in CHO cells, -10 to +4 sequences around ATG in 100 CHO genes were compared, and the extended Kozak elements with different translation intensities were constructed. Using the classic Kozak element as control, the effects of optimized extended Kozak elements on the secreted alkaline phosphatase (SEAP) and human serum albumin (HSA) gene were studied. The results showed that the optimized extended Kozak sequence can enhance the stable expression level of recombinant proteins in CHO cells. Furthermore, it was found that the increased expression level of the recombinant protein was not related with higher transcription level. In summary, optimizing extended Kozak elements can enhance the expression of recombinant proteins in CHO cells, which contributes to the construction of an efficient expression system for CHO cells.
Assuntos
Fosfatase Alcalina , Cricetulus , Proteínas Recombinantes , Células CHO , Animais , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Cricetinae , HumanosRESUMO
BACKGROUND: Osteosarcoma is considered as the most prevalent form of primary malignant bone cancer, prompting a pressing need for novel therapeutic options. Arnicolide D, a sesquiterpene lactone derived from the traditional Chinese herbal medicine Centipeda minima (known as E Bu Shi Cao in Chinese), showed anticancer efficacy against several kinds of cancers. However, its effect on osteosarcoma remains unclear. OBJECTIVE: This study aimed to investigate the anticancer activity of arnicolide D and the underlying molecular mechanism of its action in osteosarcoma cells, MG63 and U2OS. METHODS: Cell viability and proliferation were evaluated through MTT assay and colony formation assay following 24 h and 48 h treatment with different concentrations of arnicolide D. Flow cytometry was employed to examine cell cycle progression and apoptosis after 24 h treatment of arnicolide D. Western blotting was performed to determine the expression of the PI3k, Akt and m-TOR and their phosphorylated forms. RESULTS: Our findings revealed that arnicolide D treatment resulted in a significant reduction in cell viability, the inhibition of proliferation, and the induction of apoptosis and cell cycle arrest in the G2/M phase. Furthermore, arnicolide D could inhibit the activation of PI3K/Akt/mTOR pathway in osteosarcoma cells. CONCLUSION: Based on our results, arnicolide D demonstrated significant anti-osteosarcoma activity and held the potential to be considered as a therapeutic candidate for osteosarcoma in the future.
RESUMO
The phytochemical investigation on the rhizomes of Paris yunnanensis Franch. resulted in the discovery and characterisation of six compounds, including two new saponins named parisyunnanosides M-N (1-2), and four known ones (3-6). The structures of isolated compounds were determined by spectroscopic data analysis and chemical methods. Compound 2 is a pregnane-type saponin with a special α,ß-unsaturated carboxylic acid moiety at C-17, which is first discovered in genus Paris. The anti-inflammatory activity of the isolated compounds was assessed in vitro. The results demonstrated that compounds 3 and 4 could significantly inhibit the production of NO which was induced by LPS in RAW 264.7 cells with IC50 values of 0.67 ± 0.17 µM and 0.85 ± 0.12 µM, respectively.
RESUMO
BACKGROUND: Osteoporotic vertebral compression fractures (OVCF) caused by osteoporosis is a common clinical fracture type. There are many surgical treatment options for OVCF, but there is a lack of comparison among different options. Therefore, we counted a total of 104 cases of OVCF operations with different surgical plans, followed up the patients, and compared the surgical outcome indications before, after and during the follow-up. METHOD: 104 patients who underwent posterior osteotomy (Modified PSO, SPO, PSO, VCR) and kyphosis correction surgery at our hospital between April 2006 and August 2021 with a minimum follow-up period of 24 months were included. All cases were injuries induced by a fall incurred while standing or lifting heavy objects without high-energy trauma. The mean CT value was 71 HU, which was below 110 HU, indicating severe osteoporosis. The indications for surgery included gait disturbance due to severe pain with pseudarthrosis, increased kyphotic angle, and progressive neurological symptoms. Pre- and postoperative CL, TLK, TK, PrTK, TKmax, GK, LL, PI, SS, PT, SVA, TPA, were investigated radiologically. Additionally, We evaluated estimated blood loss, surgical time and perioperative symptom. RESULT: The results show, after operation, TLK (37.32 ± 10.61° vs. 11.01 ± 8.06°, P < 0.001), TK (35.42 ± 17.64° vs. 25.62 ± 12.24°, P < 0.001), TKmax (49.71 ± 16.32° vs. 24.12 ± 13.34°, P < 0.001), SVA (44.91 ± 48.67 vs. 23.52 ± 30.21, P = 0.013), CL (20.23 ± 13.21° vs. 11.45 ± 9.85°, P = 0.024) and TPA (27.44 ± 12.76° vs. 13.91 ± 9.24°, P = 0.009) were improved significantly in modified Pedicle subtraction osteotomy (mPSO) after operation. During follow-up, TLK (37.32 ± 10.61° vs. 13.88 ± 10.02°, P < 0.001) and TKmax (49.71 ± 16.32° vs. 24.12 ± 13.34°, P < 0.001) were improved significantly in Modified PSO group. In additon, estimated blood loss (790.0 ± 552.2 ml vs. 987.0 ± 638.5 ml, P = 0.038), time of operation (244.1 ± 63.0 min vs. 292.4 ± 87.6 min, P = 0.025) were favorable in Modified PSO group compared to control group. CONCLUSION: To conclude, mPSO could acquire a favorable degree of kyphosis correction as well as fewer follow-up complications. Compared with other surgical methods, it also has the advantages of less surgical trauma and shorter operation time. It can be an effective solution for the treatment of OVCF.
Assuntos
Fraturas por Compressão , Fraturas por Osteoporose , Osteotomia , Fraturas da Coluna Vertebral , Humanos , Fraturas por Compressão/cirurgia , Feminino , Masculino , Osteotomia/métodos , Idoso , Fraturas por Osteoporose/cirurgia , Fraturas da Coluna Vertebral/cirurgia , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Resultado do Tratamento , Cifose/cirurgia , Cifose/etiologiaRESUMO
High-mountain green tea, where the first new leaf hasn't yet unfurled, is prized for perceived superior quality, but this hasn't yet been verified by experimentation. Electronic sensors, whole metabolomics and sensory evaluation were employed to assess the quality of yymj (tea buds with a newly unfurled leaf) and qymj (tea buds without new leaves). The qymj proved to have significant advantages in aroma, color and shape, but still had some shortcomings in umami, bitterness and sourness. Differences in the content of volatile organic compounds (including alcohols, hydrocarbons and lipids) and nonvolatile organic compounds (flavonoids, amino acids, sugars, and phenolic acids) quality of high-mountain green teas with different maturity levels and provides well explained these quality differences. This study establishes a systematic approach to study the quality of high-mountain green tea at different maturity levels, and provides important reference information for consumers, governments and tea farmers.
Assuntos
Camellia sinensis , Metabolômica , Folhas de Planta , Paladar , Chá , Compostos Orgânicos Voláteis , Folhas de Planta/química , Folhas de Planta/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Humanos , Camellia sinensis/química , Camellia sinensis/crescimento & desenvolvimento , Camellia sinensis/metabolismo , Chá/química , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo , Adulto , Feminino , Masculino , Odorantes/análise , Flavonoides/análise , Controle de Qualidade , Adulto JovemRESUMO
Multifunctional N, Fe-doped carbon dots (N, Fe-CDs) were synthesized by the one-step hydrothermal method using ferric ammonium citrate and dicyandiamide as raw materials. The N, Fe-CDs exhibited peroxidase-like (POD) activity by catalyzing the oxidization of 3,3',5,5'-tetramethylbenzidine (TMB) to the green oxidation state ox-TMB in the presence of hydrogen peroxide (H2O2). Subsequently, based on the POD activity of N, Fe-CDs, an efficient and sensitive colorimetric method for the detection of H2O2 and ascorbic acid (AA) was established with a limit of detection of 0.40 µM and 2.05 µM. The proposed detection method has been successfully applied to detect AA in fruit juice, vitamin C tablets, and human serum samples and has exhibited excellent application prospects in biotechnology and food fields. Furthermore, N, Fe-CDs also showed a protective effect on the cell damage caused by H2O2 and could be used as an antioxidant agent.
Assuntos
Ácido Ascórbico , Carbono , Sucos de Frutas e Vegetais , Peróxido de Hidrogênio , Oxirredução , Pontos Quânticos , Peróxido de Hidrogênio/química , Ácido Ascórbico/química , Humanos , Carbono/química , Pontos Quânticos/química , Sucos de Frutas e Vegetais/análise , Benzidinas/química , Colorimetria/métodos , Limite de Detecção , Ferro/química , Nitrogênio/química , Peroxidase/química , Peroxidase/metabolismo , Antioxidantes/química , Antioxidantes/farmacologiaRESUMO
Cis-13, 16-docosadienoic acid (DDA) is an omega-6 polyunsaturated fatty acid with great potential for application in medicine and health. Using microbial cell factories for DDA production is considered a viable alternative to extracting DDA from plant seeds. In this study, using Yarrowia lipolytica Po1f (Δku70) as a chassis, firstly, the adaptation of three elongases in Po1f (Δku70) were explored. Secondly, the DDA biosynthetic pathway was redesigned, resulting in a DDA content of 0.046 % of total fatty acids (TFAs). Thirdly, through the "push-pull" strategy, the DDA content increased to 0.078 % of TFAs. By enhancing the supply of acetyl-CoA, the DDA production in the engineered strain YL-7 reached 0.391 % of the TFAs (3.19 mg/L). Through optimizing the fermentation conditions, the DDA titer of YL-7 reached 29.34 mg/L. This research achieves the sustainable biological production of DDA in Y. lipolytica.
Assuntos
Ácidos Graxos Insaturados , Yarrowia , Yarrowia/metabolismo , Yarrowia/genética , Ácidos Graxos Insaturados/metabolismo , Ácidos Graxos Insaturados/biossíntese , Engenharia Metabólica/métodos , FermentaçãoRESUMO
BACKGROUND: The treatment of infected bone defects remains a clinical challenge. With the development of three-dimensional printing technology, three-dimensional printed implants have been used for defect reconstruction. The aim of this study was to investigate the clinical outcomes of three-dimensional printed porous prosthesis in the treatment of femoral defects caused by osteomyelitis. METHODS: Eleven patients with femoral bone defects following osteomyelitis who were treated with 3D-printed porous prosthesis at our institution between May 2017 and July 2021, were included. Eight patients were diagnosed with critical-sized defects, and the other three patients were diagnosed with shape-structural defects. A two-stage procedure was performed for all patients, and the infection was eradicated and bone defects were occupied by polymethylmethacrylate spacer during the first stage. The 3D-printed prosthesis was designed and used for the reconstruction of femoral defects in the second stage. Position of the reconstructed prostheses and bone growth were measured using radiography. The union rate, complications, and functional outcomes at the final follow-up were assessed. RESULTS: The mean length of the bone defect was 14.0 cm, union was achieved in 10 (91%) patients. All patients showed good functional performance at the most recent follow-up. In the critical-sized defect group, one patient developed a deep infection that required additional procedures. Two patients had prosthetic dislocations. Radiography demonstrated good osseous integration of the implant-bone interface in 10 patients. CONCLUSION: The 3D printed prostheses enable rapid anatomical and mechanically stable reconstruction of extreme femur bone defects, effectively shortens treatment time, and achieves satisfactory clinical outcomes.
Assuntos
Fêmur , Osteomielite , Impressão Tridimensional , Desenho de Prótese , Titânio , Humanos , Osteomielite/cirurgia , Osteomielite/etiologia , Osteomielite/diagnóstico por imagem , Masculino , Feminino , Fêmur/cirurgia , Fêmur/diagnóstico por imagem , Pessoa de Meia-Idade , Adulto , Porosidade , Resultado do Tratamento , Implantação de Prótese/instrumentação , Implantação de Prótese/métodos , Implantação de Prótese/efeitos adversos , Estudos Retrospectivos , Idoso , Adulto Jovem , Procedimentos de Cirurgia Plástica/métodos , Procedimentos de Cirurgia Plástica/instrumentaçãoRESUMO
BACKGROUND: Natural medicines present a considerable analytical challenge due to their diverse botanical origins and complex multi-species composition. This inherent complexity complicates their rapid identification and analysis. Tangerine peel, a product of the Citrus species from the Rutaceae family, is widely used both as a culinary ingredient and in traditional Chinese medicine. It is classified into two primary types in China: Citri Reticulatae Pericarpium (CP) and Citri Reticulatae Pericarpium Viride (QP), differentiated by harvest time. A notable price disparity exists between CP and another variety, Citri reticulatae "Chachi" (GCP), with differences being based on the original variety. METHODS: This study introduces an innovative method using portable miniature mass spectrometry for swift on-site analysis of QP, CP, and GCP, requiring less than a minute per sample. And combined with machine learning to differentiate the three types on site, the method was used to try to distinguish GCP from different storage years. RESULTS: This novel method using portable miniature mass spectrometry for swift on-site analysis of tangerine peels enabled the characterization of 22 compounds in less than one minute per sample. The method simplifies sample processing and integrates machine learning to distinguish between the CP, QP, and GCP varieties. Moreover, a multiple-perceptron neural network model is further employed to specifically differentiate between CP and GCP, addressing the significant price gap between them. CONCLUSIONS: The entire analytical time of the method is about 1 minute, and samples can be analyzed on site, greatly reducing the cost of testing. Besides, this approach is versatile, operates independently of location and environmental conditions, and offers a valuable tool for assessing the quality of natural medicines.