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1.
J Am Chem Soc ; 146(29): 20379-20390, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39011931

RESUMO

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.

2.
Inflamm Bowel Dis ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39045635

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.

3.
J Orthop Surg Res ; 19(1): 418, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39033286

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 Viabilidade
4.
Artigo em Inglês | MEDLINE | ID: mdl-39031061

RESUMO

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.

5.
J Biotechnol ; 392: 96-102, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38960098

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.

6.
Int J Biol Macromol ; 275(Pt 2): 133654, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38972645

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 →2)-α-D-Manp-(1 â†’ 3)-ß-D-Galf-(1→, and the side chains involved α-D-Manp-(1 â†’ 6)-α-D-Manp-(1→, α-D-Manp-(1 â†’ 3)-α-D-Manp-(1→, 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.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38967079

RESUMO

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.

8.
Poult Sci ; 103(9): 104065, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-39043024

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.

9.
Nat Prod Res ; : 1-8, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38962949

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.

10.
Rapid Commun Mass Spectrom ; 38(16): e9780, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-38887892

RESUMO

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.


Assuntos
Citrus , Aprendizado de Máquina , Espectrometria de Massas , Citrus/química , Citrus/classificação , Espectrometria de Massas/métodos
11.
Biomed Environ Sci ; 37(5): 471-478, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38843920

RESUMO

Objective: Little is known about the association between whole-blood nicotinamide adenine dinucleotide (NAD +) levels and nabothian cysts. This study aimed to assess the association between NAD + levels and nabothian cysts in healthy Chinese women. Methods: Multivariate logistic regression analysis was performed to analyze the association between NAD + levels and nabothian cysts. Results: The mean age was 43.0 ± 11.5 years, and the mean level of NAD + was 31.3 ± 5.3 µmol/L. Nabothian cysts occurred in 184 (27.7%) participants, with single and multiple cysts in 100 (15.0%) and 84 (12.6%) participants, respectively. The total nabothian cyst prevalence gradually decreased from 37.4% to 21.6% from Q1 to Q4 of NAD + and the prevalence of single and multiple nabothian cysts also decreased across the NAD + quartiles. As compared with the highest NAD + quartile (≥ 34.4 µmol/L), the adjusted odds ratios with 95% confidence interval of the NAD + Q1 was 1.89 (1.14-3.14) for total nabothian cysts. The risk of total and single nabothian cysts linearly decreased with increasing NAD + levels, while the risk of multiple nabothian cysts decreased more rapidly at NAD + levels of 28.0 to 35.0 µmol/L. Conclusion: Low NAD + levels were associated with an increased risk of total and multiple nabothian cysts.


Assuntos
NAD , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , NAD/sangue , NAD/metabolismo , Cistos/sangue , Cistos/epidemiologia , China/epidemiologia
12.
Front Oncol ; 14: 1361694, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38846984

RESUMO

Background: Soft tissue tumors (STTs) are benign or malignant superficial neoplasms arising from soft tissues throughout the body with versatile pathological types. Although Ultrasonography (US) is one of the most common imaging tools to diagnose malignant STTs, it still has several drawbacks in STT diagnosis that need improving. Objectives: The study aims to establish this deep learning (DL) driven Artificial intelligence (AI) system for predicting malignant STTs based on US images and clinical indexes of the patients. Methods: We retrospectively enrolled 271 malignant and 462 benign masses to build the AI system using 5-fold validation. A prospective dataset of 44 malignant masses and 101 benign masses was used to validate the accuracy of system. A multi-data fusion convolutional neural network, named ultrasound clinical soft tissue tumor net (UC-STTNet), was developed to combine gray scale and color Doppler US images and clinic features for malignant STTs diagnosis. Six radiologists (R1-R6) with three experience levels were invited for reader study. Results: The AI system achieved an area under receiver operating curve (AUC) value of 0.89 in the retrospective dataset. The diagnostic performance of the AI system was higher than that of one of the senior radiologists (AUC of AI vs R2: 0.89 vs. 0.84, p=0.022) and all of the intermediate and junior radiologists (AUC of AI vs R3, R4, R5, R6: 0.89 vs 0.75, 0.81, 0.80, 0.63; p <0.01). The AI system also achieved an AUC of 0.85 in the prospective dataset. With the assistance of the system, the diagnostic performances and inter-observer agreement of the radiologists was improved (AUC of R3, R5, R6: 0.75 to 0.83, 0.80 to 0.85, 0.63 to 0.69; p<0.01). Conclusion: The AI system could be a useful tool in diagnosing malignant STTs, and could also help radiologists improve diagnostic performance.

13.
BMC Musculoskelet Disord ; 25(1): 474, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38880911

RESUMO

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/instrumentação
14.
Eur Spine J ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858266

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.

15.
Plant Cell Environ ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38863246

RESUMO

The shortage of decades-long continuous measurements of ecosystem processes limits our understanding of how changing climate impacts forest ecosystems. We used continuous eddy-covariance and hydrometeorological data over 2002-2022 from a young Douglas-fir stand on Vancouver Island, Canada to assess the long-term trend and interannual variability in evapotranspiration (ET) and transpiration (T). Collectively, annual T displayed a decreasing trend over the 21 years with a rate of 1% yr-1, which is attributed to the stomatal downregulation induced by rising atmospheric CO2 concentration. Similarly, annual ET also showed a decreasing trend since evaporation stayed relatively constant. Variability in detrended annual ET was mostly controlled by the average soil water storage during the growing season (May-October). Though the duration and intensity of the drought did not increase, the drought-induced decreases in T and ET showed an increasing trend. This pattern may reflect the changes in forest structure, related to the decline in the deciduous understory cover during the stand development. These results suggest that the water-saving effect of stomatal regulation and water-related factors mostly determined the trend and variability in ET, respectively. This may also imply an increase in the limitation of water availability on ET in young forests, associated with the structural and compositional changes related to forest growth.

16.
Sci Total Environ ; 944: 173961, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-38876338

RESUMO

The sulfur (S) cycle is an important biogeochemical cycle with profound implications for both cellular- and ecosystem-level processes by diverse microorganisms. Mangrove sediments are a hotspot of biogeochemical cycling, especially for the S cycle with high concentrations of S compounds. Previous studies have mainly focused on some specific inorganic S cycling processes without paying specific attention to the overall S-cycling communities and processes as well as organic S metabolism. In this study, we comprehensively analyzed the distribution, ecological network and assembly mechanisms of S cycling microbial communities and their changes with sediment depths using metagenome sequencing data. The results showed that the abundance of gene families involved in sulfur oxidation, assimilatory sulfate reduction, and dimethylsulfoniopropionate (DMSP) cleavage and demethylation decreased with sediment depths, while those involved in S reduction and dimethyl sulfide (DMS) transformation showed an opposite trend. Specifically, glpE, responsible for converting S2O32- to SO32-, showed the highest abundance in the surface sediment and decreased with sediment depths; in contrast, high abundances of dmsA, responsible for converting dimethyl sulfoxide (DMSO) to DMS, were identified and increased with sediment depths. We identified Pseudomonas and Streptomyces as the main S-cycling microorganisms, while Thermococcus could play an import role in microbial network connections in the S-cycling microbial community. Our statistical analysis showed that both taxonomical and functional compositions were generally shaped by stochastic processes, while the functional composition of organic S metabolism showed a transition from stochastic to deterministic processes. This study provides a novel perspective of diversity distribution of S-cycling functions and taxa as well as their potential assembly mechanisms, which has important implications for maintaining mangrove ecosystem functions.


Assuntos
Sedimentos Geológicos , Microbiota , Enxofre , Áreas Alagadas , Sedimentos Geológicos/microbiologia , Sedimentos Geológicos/química , Enxofre/metabolismo , Bactérias/metabolismo , Bactérias/classificação , Bactérias/genética
17.
Bioresour Technol ; 406: 130978, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38879057

RESUMO

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 , Fermentação
18.
Mikrochim Acta ; 191(7): 384, 2024 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-38861028

RESUMO

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/farmacologia
19.
BMC Geriatr ; 24(1): 544, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38909190

RESUMO

BACKGROUND: The accelerated growth of older individuals worldwide has increased the number of patients presenting with fragility hip fractures. Having a hip fracture can cause excess mortality, and patients with hip fracture have a higher risk of death than those without hip fracture. Most studies have treated hip fracture as a single, homogeneous condition, but hip fracture includes two major anatomic types: intertrochanteric fracture and femoral neck fracture. Few studies have specifically evaluated 1-year mortality risk in older individuals with femoral intertrochanteric fracture. The aim of this study was to evaluate 1-year mortality and factors associated with mortality in older individuals with femoral intertrochanteric fracture. METHODS: A retrospective review was conducted of 563 patients ≥ 65 years old who underwent surgery for femoral intertrochanteric fractures at our institution between January 2010 and August 2018. Patient demographics, comorbidities, and treatment were collected by retrospective chart review. Age, sex, Body Mass Index (BMI), American Society of Anesthesiologists (ASA) classification, Charlson comorbidity index (CCI), Arbeitsgemeinschaft Für Osteosynthesefragen (AO) fracture classification, haemoglobin value at admission, time to surgery, operation time, and intraoperative blood loss were risk factors to be tested. Multivariable logistic regression was used to evaluate associations between variables and death. RESULTS: Among the 563 patients, 49 died within 1 year after surgery, and the 1-year mortality rate was 8.7%. Multivariate analysis identified age > 80 years (OR = 4.038, P = 0.011), haemoglobin < 100 g/l (OR = 2.732, P = 0.002), ASA score ≥ 3 (OR = 2.551, P = 0.005), CCI ≥ 3 (OR = 18.412, P = 0.018) and time to surgery > 14 d (OR = 3.907, P = 0.030) as independent risk factors for 1-year mortality. Comorbidities such as myocardial infarction and chronic pulmonary disease were associated with 1-year mortality after adjusting for age > 80 years and time to surgery > 14 days. CONCLUSIONS: Patients over 80 years old with haemoglobin < 100 g/l, ASA score ≥ 3, CCI ≥ 3, and multiple comorbidities, especially myocardial infarction and chronic pulmonary disease before surgery, are at a higher risk of 1-year mortality. Doctors should pay more attention to these vulnerable patients, and a surgical delay greater than 14 days should be avoided.


Assuntos
Fraturas do Quadril , Centros de Atenção Terciária , Humanos , Masculino , Feminino , Idoso , Estudos Retrospectivos , Fraturas do Quadril/mortalidade , Fraturas do Quadril/cirurgia , China/epidemiologia , Idoso de 80 Anos ou mais , Fatores de Risco , Centros de Atenção Terciária/tendências , Medição de Risco/métodos
20.
Food Chem ; 457: 140119, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38936125

RESUMO

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.

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