Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 710
Filtrar
1.
Biotechnol Adv ; 77: 108465, 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39413888

RESUMO

Energy produced from renewable sources such as sun or wind are intermittent, depending on circumstantial factors. This fact explains why energy supply and demand do not match. In this context, the interest in biomethanation has increased as an interesting contribution to the Power-to-gas concept (P2G), transforming the extra amount of produced electricity into methane (CH4). The reaction between green hydrogen (H2) (produced by electrolysis) and CO2 (pollutant present in biogas) can be catalysed by different microorganisms to produce biomethane, that can be injected into existing natural gas grid if reaching the standards. Thus, energy storage for both hydrogen and electricity, as well as transportation problems would be solved. However, H2 diffusion to the liquid phase for its further biological conversion is the main bottleneck due to the low solubility of H2. This review includes the state-of-the-art in biological hydrogenotrophic methanation (BHM) and membrane-based technologies. Specifically, the use of hollow-fiber membrane bioreactors as a technology to overcome H2 diffusion limitations is reviewed. Furthermore, the influence of operating conditions, microbiology, H2 diffusion and H2 injection methods are critically discussed before setting the main recommendations about BHM.

2.
Heliyon ; 10(19): e38456, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39391477

RESUMO

High-quality economic development relies on industrial transformation and upgrading. To promote industrial transformation and upgrading, efficient fiscal expenditures are undoubtedly important as pillars of national governance. However, in the context of the market economy, the government's excessive intervention in industrial development will lead to the "promotion tournament" of officials and the "beggar-thy-neighbor" local protectionism, resulting in the convergence of regional industrial structure, which will bring uncertain impact on the upgrading of regional industrial structure. Thus, this study empirically assesses how public fiscal expenditure impacts industrial transformation and upgrading as well as the mechanism by developing a spatial econometric model using the panel data of 250 Chinese cities from 2007 to 2020 and further discusses the differential impact from the perspective of urban scale. The findings disclose that public fiscal expenditure serves a crucial role in facilitating industrial transformation and upgrading, but their relationship resembles an inverted U. Therefore, an optimal scale of public fiscal expenditure exists. Heterogeneity findings reveal that the promoting effect of public fiscal expenditure on industrial transformation and upgrading decreases with the expansion of the city scale. The role mechanism implies that public fiscal expenditure indirectly leverages industrial transformation and upgrading through promoting technological innovation, reducing resource dependence, and expanding scale economies. The conclusion provides a theoretical and practical framework for the government to optimize public fiscal expenditure, promote the transformation and upgrading of China's industrial structure, and ultimately attain high-quality development.

3.
J Environ Manage ; 370: 122780, 2024 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-39396486

RESUMO

Improving the efficiency of anaerobic digestion (AD) of sewage sludge (SS) is a critical step toward the achievement of energy neutrality in wastewater treatment plants (WWTPs), as required by the European Green Deal. This study used a comparative techno-economic assessment (TEA) to evaluate the feasibility of producing biomethane, at a WWTP, through upgrading biogas with a double-stage permeation membrane plant. The biogas was originally generated from the AD of a mixture of primary sludge (PS) and either raw or pre-treated waste activated sludge (WAS), where biological or thermo-alkali pre-treatments were applied to increase the WAS intrinsic low degradability. The TEA was supported by the results of pilot-scale tests, carried out on WAS, which mimicked (i) a traditional mesophilic AD process; (ii) a two-stage AD process, where a temperature-phased anaerobic digestion (TPAD, 3 days, 55 °C + 20 days, 38 °C) was performed to biologically pre-treat WAS; (iii) a traditional mesophilic AD process preceded by a thermo-alkali (4 g NaOH/100 g TS, 90 °C, 90 min) pre-treatment. The TEA was carried out in two phases. In the first, the minimum size of the WWTP capable of making the costs necessary for the implementation of the biogas upgrading plant equal to the revenues coming from selling biomethane (at 62 €/MWh) in 10 years was calculated in the absence of pre-treatments. It resulted of 500,000 equivalent inhabitants (e.i.). In the second phase, for the WWTP size found previously, the effect of either biological or thermo-alkali pre-treatments on the economic balance was evaluated, that is the gain (or the loss) associated to the selling of biomethane, compared to the reference price of 62 €/MWh. It was found that the TPAD increased the biogas productivity by only 23.6%, too little to compensate the amount of heat necessary for the pre-treatment and the purchase cost of the additional reactor. Conversely, the thermo-alkali pre-treatment, which enhanced the WAS biogas productivity by 110%, increased the biomethane revenues by approx. 10 €/MWh, compared to the scenario without pre-treatments. This study offers useful data to WWTP managers who want to introduce WAS pre-treatments, combined with interventions for biogas upgrading, in a new or existing sludge line of a WWTP.

4.
J Environ Manage ; 370: 122862, 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39405881

RESUMO

Siloxanes (VMS) represent a class of organosilicon compounds known for their adverse effects on both the environment and human health. Their presence in biogas significantly hinders its economic valorisation, highlighting the need for effective treatment methods. This study investigates the performance of three different packing materials in the anoxic biofiltration of VMS (L2, L3, D4 and D5). The materials evaluated included plastic rings (BTF-1), polyurethane foam (BTF-2) and plastic rings combined with activated carbon (80:20) (BTF-3). Among them, BTF-3 exhibited superior performance, achieving maximum VMS removal efficiencies (REs) of 90%, including the complete elimination of L3 and D4, and ∼80% removal of D5, attributed to the presence of activated carbon. However, the abatement of L2 was inferior to that of other VMS (<80%), which was attributed to the activated carbon's affinity for larger molecular weights and critical diameters. In contrast, BTF-1 and BTF-2 supported maximum VMS removals of 40%. Notably, neither increasing the trickling liquid velocity from 2 to 4.5 m h⁻1 nor adding Fe-carbon nanoparticles to the solution had any impact on the BTFs' performance. Following the successful results observed in BTF-3, gas residence time was reduced from 60 to 42 min, consequently leading to an increase in the EC from 366 to 509 mg m-3 h-1 (corresponding to an RE = 87%). Despite the different performance of the BTFs, comparable bacterial communities were identified, dominated by the genera Thermomonas, Corynebacterium, Aquimonas, Thauera and Parvibaculum. The results obtained in this study highlighted the potential of activated carbon as packing material for enhancing abatement performance during biotrickling filtration and identified new bacterial genera with potential for VMS degradation.

5.
Chem Asian J ; : e202400999, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39385524

RESUMO

The sustainable development of energy has always been a concern. Upgrading biomass catalysis into hydrocarbon liquid fuels is one of the effective methods. In order to upgrade biomass derivative guaiacol by Hydrodeoxygenation (HDO) catalysis, this article report a three-dimensional honeycomb structure biochar loaded with Ni nanoparticles and phosphomolybdic acid demonstrating excellent catalytic performance in a short period of time. This is due to the porous structure of biochar, which allows Ni metal nanoparticles to be highly uniformly dispersed on the support, which enhances the catalytic hydrogenation of guaiacol in terms of both rate and efficiency. Furthermore, it was observed that the added phosphomolybdic acid dissolved within the temperature range of 78-90°C, functioning as a homogeneous catalyst in the process. This proves advantageous, as the phosphomolybdic acid becomes accessible at any location within the porous Ni/C catalyst. The detailed characterization data revealed that the carbon support prepared in this study has a high specific surface area of up to 1375.61 m2/g. Additionally, the phosphomolybdic acid exhibited rich acidity, with Brønsted and Lewis acid contents of 2.55 µmol/g and 21.45 µmol/g, respectively. Reaction data demonstrated that at 240°C for 180 minutes, 100% conversion and 97.9% cyclohexane selectivity were achieved.

6.
Bioresour Technol ; 413: 131524, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39321937

RESUMO

The methanation efficiency and operational stability of a 2 m3 pilot-scale in-situ biomethanation reactor were investigated using on-site sewage sludge as the substrate, at a wastewater treatment plant. In parallel, a laboratory-scale study was conducted. Hydrogen conversion efficiencies of 96.7 and 97.5 %, and average methane contents of 84.2 and 83.2 % were obtained, for the laboratory and pilot experiments, respectively. The pilot-scale digester was operated at various conditions for 137 d, of which the last 30 d were stable with a high biomethanation efficiency and an average pH of 8.2. Gas recirculation increased the hydrogen conversion efficiency. When hydrogen injection and gas recirculation were applied separately, a 96 % lower gas recirculation rate was needed to achieve the same hydrogen conversion efficiency, compared to a mixture of hydrogen injection and gas recirculation in the same line. These findings may facilitate the selection of suitable gas recirculation concepts for practical biomethanation applications.


Assuntos
Hidrogênio , Metano , Esgotos , Projetos Piloto , Reatores Biológicos , Gases , Concentração de Íons de Hidrogênio
7.
Bioresour Technol ; 413: 131421, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39233186

RESUMO

Anaerobic digestion (AD) is an environmentally friendly technology that simultaneously stabilizes biowaste and produces biogas. Conventional AD faces challenges such as inadequate substrate degradation and low methane purity. Pressure-centric regulation serves as an AD optimization strategy that can enhance the digestion efficiency and generate higher-energy-value biogas. However, limited reviews have been undertaken to focus on this technology. This review is designed to discuss innovations in ex-situ high-pressure pretreatment and in-situ high-pressure anaerobic digestion (HPAD) processes. Moreover, comprehensive understandings on the intrinsic mechanisms of HPAD are critically examined, including physicochemical reaction principles and microbial responses. The constraints currently curtailing these technologies and potential mitigation strategies are also scrutinized. Additionally, current knowledge gaps and future research directions on mechanisms, model fitting, and engineering practices are presented. Overall, this work highlights the feasibility of pressure-centric regulated AD and provides novel insights to overcome existing technical barriers in its application.


Assuntos
Biocombustíveis , Pressão , Anaerobiose , Metano/metabolismo , Reatores Biológicos
8.
Polymers (Basel) ; 16(18)2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39339031

RESUMO

Mixed plastic packaging waste sorting residue (MPO323) was treated by thermal pyrolysis to utilize pyrolysis oil and char. The pyrolysis oil was found to contain aromatic and aliphatic hydrocarbons. The chlorine and bromine contents were as high as 40,000 mg/kg and 200 mg/kg, respectively. Additionally, other elements like sulfur, phosphorous, iron, aluminum, and lead were detected, which can be interpreted as impurities relating to the utilization of oils for chemical recycling. The pyrolysis char showed high contents of potentially active species like silicon, calcium, aluminum, iron, and others. To enhance the content of aromatic hydrocarbons and to reduce the level of contaminants, pyrolysis oil was reformed with the corresponding pyrolysis char to act as an active material in a fixed bed. The temperature of the reactor and the flow rate of the pyrolysis oil feed were varied to gain insights on the cracking and reforming reactions, as well as on performance with regard to decontamination.

9.
Molecules ; 29(18)2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39339320

RESUMO

Biomass can be converted into energy/fuel by different techniques, such as pyrolysis, gasification, and others. In the case of pyrolysis, biomass can be converted into a crude bio-oil around 50-75% yield. However, the direct use of this crude bio-oil is impractical due to its high content of oxygenated compounds, which provide inferior properties compared to those of fossil-derived bio-oil, such as petroleum. Consequently, bio-oil needs to be upgraded by physical processes (filtration, emulsification, among others) and/or chemical processes (esterification, cracking, hydrodeoxygenation, among others). In contrast, hydrodeoxygenation (HDO) can effectively increase the calorific value and improve the acidity and viscosity of bio-oils through reaction pathways such as cracking, decarbonylation, decarboxylation, hydrocracking, hydrodeoxygenation, and hydrogenation, where catalysts play a crucial role. This article first focuses on the general aspects of biomass, subsequent bio-oil production, its properties, and the various methods of upgrading pyrolytic bio-oil to improve its calorific value, pH, viscosity, degree of deoxygenation (DOD), and other attributes. Secondly, particular emphasis is placed on the process of converting model molecules and bio-oil via HDO using catalysts based on nickel and nickel combined with other active elements. Through these phases, readers can gain a deeper understanding of the HDO process and the reaction mechanisms involved. Finally, the different equipment used to obtain an improved HDO product from bio-oil is discussed, providing valuable insights for the practical application of this reaction in pyrolysis bio-oil production.

10.
Environ Sci Pollut Res Int ; 31(43): 55388-55409, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39230809

RESUMO

Urban industrial pollution plays a dominant role in environmental pollution in China. Exploring the digital governance path of urban industrial pollution can provide strong support for improving environmental quality. This article empirically investigates the role and path of digitalization in the governance of urban industrial pollution from three dimensions: economic scale, structural scale, and technological scale. The results show that there is an inverted "U"-shaped relationship between digitalization and urban industrial pollution, with initial promotion followed by suppression. Among them, economic scale, industrial transformation and upgrading, and green innovation are the paths for digital governance of urban industrial pollution. In addition, there is a chain path of "green innovation-industrial transformation and upgrading" between the two. Through spatial Durbin model and regional heterogeneity analysis, it is found that digitalization has a spatial spillover effect on urban industrial pollution control, and eastern regions, regions with high economic development level and industrialized cities benefit more from digital urban industrial pollution control. The research conclusions of this article provide references for the Chinese government to formulate relevant policies, deepen the integration of digitalization and urban industrial pollution, and promote digital governance of urban industrial pollution.


Assuntos
Cidades , Poluição Ambiental , China , Indústrias
11.
Explor Target Antitumor Ther ; 5(4): 981-996, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39280242

RESUMO

Accurate identification of prostate cancer Gleason grade group remains an important component of the initial management of clinically localized disease. However, Gleason score upgrading (GSU) from biopsy to radical prostatectomy can occur in up to a third of patients treated with surgery. Concern for disease undergrading remains a source of diagnostic uncertainty, contributing to both over-treatment of low-risk disease as well as under-treatment of higher-risk prostate cancer. This review examines the published literature concerning risk factors for GSU from time of biopsy to prostatectomy final pathology. Risk factors identified for Gleason upgrading include patient demographic and clinical factors including age, body mass index, race, prostate volume, and biomarker based assays, including prostate-specific antigen (PSA) density, and testosterone values. In addition, prostate magnetic resonance imaging (MRI) findings have also been associated with GSU. Biopsy-specific characteristics associated with GSU include lower number of biopsy cores and lack of targeted methodology, and possibly increasing percent biopsy core positivity. Recognition of risk factors for disease undergrading may prompt confirmatory testing including repeat sampling or imaging. Continued refinements in imaging guided biopsy techniques may also reduce sampling error contributing to undergrading.

12.
Transl Androl Urol ; 13(8): 1378-1387, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39280670

RESUMO

Background: Gleason grade group (GG) upgrading is associated with increased biochemical recurrence (BCR), local progression, and decreased cancer-specific survival (CSS) in prostate cancer (PCa). However, descriptions of the risk factors of GG upgrading are scarce. The objective of this study was to identify risk factors and establish a model to predict GG upgrading. Methods: There were 361 patients with PCa who underwent radical prostatectomy between May 2011 and February 2022 enrolled. Univariate and multivariate logistic regression analyses were identified and nomogram further narrowed down the contributing factors in GG upgrading. The correction curve and decision curve were used to assess the model. Results: In the overall cohort, 141 patients had GG upgrading. But the subgroup cohort (GG ≤2) showed that 68 patients had GG upgrading. Multivariate logistic regression analysis showed that in the overall cohort, total prostate-specific antigen (tPSA) ≥10 ng/mL, systemic immune-inflammation index (SII) >379.50, neutrophil-lymphocyte ratio (NLR) >2.13, the GG of biopsy ≥3, the number of positive cores >3 were independent risk factors in GG upgrading. In the cohort of biopsy GG ≤2, multivariate logistic regression showed that the tPSA ≥10 ng/mL, SII >379.50 and the number of positive cores >3 were independent risk factors in GG upgrading. A novel model predicting GG upgrading was established based on these three parameters. The area under the curve (AUC) of the prediction model was 0.759. The C-index of the nomogram was 0.768. The calibration curves of the model showed good predictive performance. Clinical decision curves indicated clinical benefit in the interval of 20% to 90% of threshold probability and good clinical utility. Conclusions: Combined levels of tPSA, SII and the positive biopsy cores distinguish patients with high-risk GG upgrading in the group of biopsy GG ≤2 and are helpful in the decision of treatment plans.

13.
J Environ Manage ; 370: 122338, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39288490

RESUMO

Achieving natural resource utilization efficiency (NRUE) is a critical objective in addressing the pressing challenges of climate change and the risks associated with the finite availability of mineral resources. Enhancing NRUE can mitigate environmental impacts and support sustainable development for future generations. In this context, green innovation emerges as a pivotal driver of environmental sustainability and resource conservation. However, its potential role in advancing the NRUE has not been fully explored. To fill this gap, this study conducts an empirical analysis of 268 Chinese cities from 2010 to 2022, examining the impact of green innovation on NRUE. This study also incorporates the mediating role of environmental regulations in shaping this impact. The findings demonstrate that green innovation significantly enhances NRUE, primarily by facilitating industrial structural upgrading and reducing resource dependence. Additionally, environmental regulations strengthen the positive effects of green innovation, further amplifying its contribution to NRUE. Moreover, geographical location and differences in resource endowments among cities lead to variations in the effectiveness of green innovation on NRUE. These findings underscore the complex interplay between green technological progress, proactive government policies, and NRUE, offering valuable insights for policymakers and researchers alike.

14.
Acad Radiol ; 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39271380

RESUMO

PURPOSE: Our aim is to develop and validate an MRI-based diagnostic model for predicting pathological deterioration upgrading in rectal tumor. METHODS: This retrospective study included 158 eligible patients from January 2017 to November 2023. The patients were divided into a training group (n = 110) and a validation group (n = 48). Radiomics features were extracted from T2-weighted images to create a radiomics score model. Significant factors identified through multifactor analysis were used to develop the final clinical feature model. By combining these two models, an combined radiomics-clinical model was established. The model's performance was evaluated using Receiver Operating Characteristic (ROC) analysis and the Area Under the ROC Curve (AUC). RESULTS: A total of 1197 features were extracted, with 11 features selected for calculating the radiomics score to establish the radiomics model. This model demonstrated good predictive performance for pathological upgrading in both the training and validation groups (AUC of 0.863 and 0.861, respectively). Clinical factors such as chief complaint and differential carcinoembryonic antigen levels showed statistical significance (P < 0.05). The clinical model, incorporating these factors, yielded AUC values of 0.669 and 0.651 for the training and validation groups, respectively. Furthermore, the radiomics-clinical combined model outperformed the individual models in predicting preoperative pathological upgrading in both the training and validation groups (AUC of 0.932 and 0.907, respectively). CONCLUSIONS: A radiomics-clinical model, which combines clinical features with radiomics features based on MRI, can predict pathological deterioration upgrading in patients with rectal tumor and provide valuable insights for personalized treatment strategies.

15.
Waste Manag Res ; : 734242X241273800, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39279233

RESUMO

This study evaluates the use of carbon-encapsulated zero-valent iron nanoparticles for biogas upgrading in wet systems. The nanoparticles were produced by hydrothermal carbonization, using olive mill waste (OMW) or microalgae as carbon sources. The solids were characterized to investigate the specific surface area, total and zero-valent iron content, pHPZC and chemical and crystalline composition. Their adsorption performance towards hydrogen sulphide (H2S) was tested by treating two types of synthetic biogas with and without CO2. In both cases, the starting H2S concentration was approximately 60 ppm and the experiments lasted until the complete saturation of the nanoparticles. Optimal Fe/C ratios of 0.05 for OMW nanoparticles and 0.2 for microalgae nanoparticles demonstrated H2S-specific adsorption capacities of 9.66 and 9.55 mgH2SgCE-nZVI-1, respectively, in a synthetic biogas without CO2. The addition of CO2 in biogas reduced adsorption, possibly due to system acidification. X-ray photoelectron spectroscopy analysis revealed surface compounds on the surface of the spent nanoparticles, including disulphides, polysulphides and sulphate. The saturated adsorbents were effectively regenerated with air, leading to the oxidation of sulphur species and desorption. The regeneration allowed a total adsorption capacity of 53.25 and 34.14 mgH2SgCE-nZVI-1, after 10 consecutive cycles of adsorption/regeneration with a single batch of olive mill and microalgae nanoparticles, respectively.

16.
Heliyon ; 10(17): e36605, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39296071

RESUMO

As a key measure to realize Chinese-style modernization, the construction of new urbanization injects new vitality into China 's urban economic growth by building a modern industrial system, and it is also of great significance to improve urban economic resilience. This study examines data from 278 Chinese cities spanning the period 2006-2022, utilizing a multi-period Difference-in-Differences model and a moderating effect model to investigate the impact of new urbanization on cities' economic resilience. The findings indicate that the adoption of modern urbanization significantly enhances cities' economic resilience. Notably, when examined from the perspectives of geographical location, urban scale, urban agglomeration, and urban economic development level, the impact of new urbanization is particularly pronounced in the eastern region, small cities, non-urban agglomeration cities, and cities with lower levels of economic development. The mechanism test demonstrates that new urbanization affects cities' economic resilience by fostering technological innovation and upgrading the industrial structure. Essentially, technological innovation and industrial restructuring serve as intermediaries in fortifying economic resilience through the implementation of new urbanization. As a result, recommendations are formulated to bolster the resilience of urban economies.

17.
Front Oncol ; 14: 1449080, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39324001

RESUMO

Introduction: The management of patients with low-grade cervical intraepithelial neoplasia (CIN1) remains controversial. We analyzed the pathological upgrading rates of patients with CIN1 undergoing conization, identifying influencing factors, and compared their outcomes to those of patients with CIN1 receiving follow-up only. Methods: This retrospective study included 466 patients with CIN1 confirmed by histopathology and treated with conization. Postoperative pathological upgrading was determined and its influencing factors were identified. We also analyzed post-conization outcomes, examining the rate of persistent/recurrent CIN1 and its influencing factors, and comparing these results to those of patients receiving follow-up only. Results: The pathological upgrading rate of patients with CIN1 after conization was 21.03% (98/466), and the influencing factors were preoperative high-risk human papillomavirus (HR-HPV) infection and cytological results. The upgrading rates of HR-HPV positive and negative patients were 22.05% and 0.00%, respectively (χ 2 = 5.03, P=0.03). The upgrading rate of patients with cytological results negative for intraepithelial lesion malignancy was 10.94%, while the upgrading rates of atypical squamous cells, cannot exclude high-grade lesion(ASC-H) and high-grade squamous intraepithelial lesion(HSIL) groups were 47.37% and 52.94%, respectively (χ 2 = 22.7, P=0.03). Persistent/recurrent CIN1 rates in the conization group were 21.24%, 15.97%, and 6.67% at 6, 12, and 24 months, respectively, significantly lower than those in the follow-up only group. The CIN2 progression rate in the conization group (0.26%) during the 24-month follow-up period was also significantly lower than that in the follow-up only group (15.15%; χ 2 = 51.68, P<0.01). The only factor influencing postoperative persistent/recurrent CIN1 was preoperative HR-HPV status. No patients who were HR-HPV negative preoperatively exhibited persistent/recurrent CIN1, compared with 25.55% of those who were HR-HPV positive preoperatively (χ 2 = 4.40, P=0.04). Discussion: The risk of progression to CIN2+ in the medium term is higher in patients with CIN1 receiving follow-up than in those undergoing conization. Doctors should refer to the guidelines but comprehensively consider age, fertility requirements, preoperative HR-HPV and cytological results, follow-up conditions, and other factors to select the most appropriate treatment strategy for patients with CIN1.

18.
Molecules ; 29(16)2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39203012

RESUMO

2,3-butanediol (2,3-BD) is a versatile bio-based platform chemical. An artificial four-enzyme synthetic biosystem composed of ethanol dehydrogenase, NADH oxidase, formolase and 2,3-butanediol dehydrogenase was designed for upgrading ethanol to 2,3-BD in our previous study. However, a key challenge in developing in vitro enzymatic systems for 2,3-BD synthesis is the relatively sluggish catalytic efficiency of formolase, which catalyzes the rate-limiting step in such systems. Herein, this study reports how engineering the tunnel and substrate binding pocket of FLS improved its catalytic performance. A series of single-point and combinatorial variants were successfully obtained which displayed both higher catalytic efficiency and better substrate tolerance than wild-type FLS. Subsequently, a cell-free biosystem based on the FLS:I28V/L482E enzyme was implemented for upgrading ethanol to 2,3-BD. Ultimately, this system achieved efficient production of 2,3-BD from ethanol by the fed-batch method, reaching a concentration of 1.39 M (124.83 g/L) of the product and providing both excellent productivity and yield values of 5.94 g/L/h and 92.7%, respectively. Taken together, this modified enzymatic catalysis system provides a highly promising alternative approach for sustainable and cost-competitive production of 2,3-BD.


Assuntos
Oxirredutases do Álcool , Butileno Glicóis , Etanol , Butileno Glicóis/metabolismo , Butileno Glicóis/química , Etanol/metabolismo , Oxirredutases do Álcool/metabolismo , Oxirredutases do Álcool/química , NADH NADPH Oxirredutases/metabolismo , NADH NADPH Oxirredutases/química , Complexos Multienzimáticos/metabolismo , Complexos Multienzimáticos/química , Álcool Desidrogenase/metabolismo , Álcool Desidrogenase/química
19.
BMC Gastroenterol ; 24(1): 253, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39118045

RESUMO

BACKGROUND: The pathological results obtained from endoscopic forceps biopsy (EFB) do not always align with the findings of postoperative endoscopic submucosal dissection (ESD). Furthermore, as ESD becomes more widespread, the number of noncurative endoscopic cases increases; thus, an accurate preoperative diagnosis and an appropriate treatment method are crucial. The purpose of this study was to explore the risk factors for postoperative pathological upgrading and noncurative resection and to gather experience in clinical and pathological diagnosis. METHODS: From March 2016 to November 2023, 292 ESD specimens were collected from 262 patients with gastric mucosal lesions. Clinicopathological information, the coincidence rate of pathological diagnosis between EFB and ESD specimens, and risk factors related to noncurative resection were analyzed retrospectively. RESULTS: The overall upgraded pathological diagnosis rate between EFB and ESD was 26.4%. The independent predictors for the upgraded group included proximal stomach lesions, lesion size > 2 cm, surface ulceration, and surface nodules. Twenty of the 235 early gastric cancer (EGC) patients underwent noncurative ESD resection. Multivariate analysis showed that undifferentiated carcinoma and tumor infiltration into the submucosa were significantly associated with noncurative resection. CONCLUSION: Biopsy cannot fully represent the lesions of gastric intraepithelial neoplasia (GIN). When a suspected epithelial dysplasia is suspected, a careful endoscopic examination should be conducted to evaluate the lesion site, size, and surface characteristics to ensure an accurate diagnosis. Noncurative endoscopic resection is associated with undifferentiated carcinoma and submucosal infiltration. Clinicians must be familiar with these predictive factors for noncurative resection and select the appropriate treatment for their patients.


Assuntos
Ressecção Endoscópica de Mucosa , Mucosa Gástrica , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/patologia , Feminino , Masculino , Mucosa Gástrica/patologia , Mucosa Gástrica/cirurgia , Fatores de Risco , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Biópsia/métodos , Gastroscopia/métodos , Adulto , Idoso de 80 Anos ou mais
20.
Bioresour Technol ; 408: 131225, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39111397

RESUMO

Biomethanation represents a promising approach for biomethane production, with biofilm-based processes like trickle bed reactors (TBRs) being among the most efficient solutions. However, maintaining stable performance can be challenging, and both pure and mixed culture approaches have been applied to address this. In this study, inocula enriched with hydrogenotrophic methanogens were introduced to to TBRs as bioaugmentation strategy to assess their impacts on the process performance and microbial community dynamics. Metagenomic analysis revealed a metagenome-assembled genome belonging to the hydrogenotrophic genus Methanobacterium, which became dominant during enrichment and successfully colonized the TBR biofilm after bioaugmentation. The TBRs achieved a biogas production with > 96 % methane. The bioaugmented reactor consumed additional H2. This may be due to microbial species utilizing CO2 and H2 via various CO2 reduction pathways. Overall, implementing bioaugmentation in TBRs showed potential for establishing targeted species, although challenges remain in managing H2 consumption and optimizing microbial interactions.


Assuntos
Reatores Biológicos , Dióxido de Carbono , Hidrogênio , Metano , Hidrogênio/metabolismo , Reatores Biológicos/microbiologia , Dióxido de Carbono/metabolismo , Metano/metabolismo , Biocombustíveis/microbiologia , Biofilmes , Methanobacterium/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA