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1.
Water Res ; 261: 122048, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38981353

RESUMEN

This study explored the potential application of plasma coupling ionic liquid on disintegration of waste activated sludge and enhanced production of short-chain fatty acids (SCFAs) in anaerobic fermentation. Under optimal conditions (dosage of ionic liquid [Emim]OTf = 0.1 g/g VSS (volatile suspended solids) and discharge power of dielectric barrier discharge plasma (DBD) = 75.2 W), the [Emim]OTf/DBD pretreatment increased SCFA production by 302 % and acetic acid ratio by 53 % compared to the control. Mechanistic investigations revealed that the [Emim]OTf/DBD combination motivated the generation of various reactive species (such as H2O2, O3, •OH, 1O2, ONOO-, and •O2-) and enhanced the utilization of physical energies (such as heat). The coupling effects of [Emim]OTf/DBD synergistically improved the disintegration of sludge and biodegradability of dissolved organic matter, promoting the sludge anaerobic fermentation process. Moreover, the [Emim]OTf/DBD pretreatment enriched hydrolysis and SCFAs-forming bacteria while inhibiting SCFAs-consuming bacteria. The net effect was pronounced expression of genes encoding key enzymes (such as alpha-glucosidase, endoglucanase, beta-glucosidase, l-lactate/D-lactate dehydrogenase, and butyrate kinase) involved in the SCFA-producing pathway, enhancing the production of SCFAs from sludge anaerobic fermentation. In addition, [Emim]OTf/DBD pretreatment facilitated sludge dewatering and heavy metal removal. Therefore, [Emim]OTf/DBD pretreatment is a promising approach to advancing sludge reduction, recyclability, and valuable resource recovery.

2.
Chem Sci ; 15(23): 8993-8999, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38873081

RESUMEN

Aromatization-driven deconstruction and functionalization of spiro dihydroquinazolinones via dual photoredox/nickel catalysis is developed. The aromatization effect was introduced to synergistically drive unstrained cyclic C-C bond cleavage, with the aim of overcoming the ring-size limitation of nitrogen-centered radical induced deconstruction of carbocycles. Herein, we demonstrate the synergistic photoredox/nickel catalyzed deconstructive cross-coupling of spiro dihydroquinazolinones with organic halides. Remarkably, structurally diverse organic halides including aryl, alkenyl, alkynyl, and alkyl bromides were compatible for the coupling. In addition, this protocol is also characterized by its mild and redox-neutral conditions, excellent functional group compatibility, high atom economy, and easy scalability. A telescoped procedure involving condensation and ring-opening/coupling was found to be accessible. This work provides a complementary strategy to the existing radical-mediated C-C bond cleavage of unstrained carbocycles.

3.
Environ Sci Technol ; 58(26): 11447-11458, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38899977

RESUMEN

Mine tailings are extremely oligotrophic environments frequently contaminated with elevated As and Sb, making As(III) and Sb(III) oxidation potentially important energy sources for the tailing microbiome. Although they have been proposed to share similar metabolic pathways, a systemic comparison of the As(III) and Sb(III) oxidation mechanisms and energy utilization efficiencies requires further elucidation. In this study, we employed a combination of physicochemical, molecular, and bioinformatic analyses to compare the kinetic and genetic mechanisms of As(III) and Sb(III) oxidation as well as their respective energy efficiencies for fueling the key nutrient acquisition metabolisms. Thiobacillus and Rhizobium spp. were identified as functional populations for both As(III) and Sb(III) oxidation in mine tailings by DNA-stable isotope probing. However, these microorganisms mediated As(III) and Sb(III) oxidation via different metabolic pathways, resulting in preferential oxidation of Sb(III) over As(III). Notably, both As(III) and Sb(III) oxidation can facilitate nitrogen fixation and phosphate solubilization in mine tailings, with Sb(III) oxidation being more efficient in powering these processes. Thus, this study provided novel insights into the microbial As(III) and Sb(III) oxidation mechanisms and their respective nutrient acquisition efficiencies, which may be critical for the reclamation of mine tailings.


Asunto(s)
Oxidación-Reducción , Antimonio/metabolismo , Minería , Arsénico/metabolismo
4.
Surg Endosc ; 38(7): 3828-3837, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38822144

RESUMEN

BACKGROUND: No consensus has been concluded with regarding to the scope of lymph node (LN) dissection for Siewert type II and III adenocarcinoma of the esophagogastric junction (AEG). This study aimed to explore risk factors for lower perigastric LN (LPLN) metastases (including no. 4d, 5, 6, and 12a LN stations) and analyze the indications for LPLN dissection. METHODS: In total, 302 consecutive patients with Siewert type II and III AEG who underwent total gastrectomy (TG) were enrolled. The logistic regression model was used to perform uni- and multivariate analyses of risk factors for LPLN metastases. Kaplan-Meier curves were used for survival analysis, and log-rank tests were used for group comparisons. Basing on the guidelines of Japanese Gastric Cancer Association, the LN metastases (LNM) as well as the efficiency index (EI) of each LN station was further evaluated. RESULTS: The independent risk factors for LPLN metastases in patients with Siewert type II and III AEG were distance from the esophagogastric junction (EGJ) to the distal end of the tumor (> 4.0 cm), preoperative carcinoembryonic antigen (CEA) ( +), pT4 stage, and HER-2 ( +). LPLN metastases was an independent risk factor for overall survival following TG. The LNM and EI of LPLN were 8.6% and 2.31%, respectively. The LNM of LPLN > 10% under the stratification of the distance from the EGJ to the distal end of the tumor (> 4.0 cm), pT4, preoperative CEA ( +), and HER-2 ( +) exhibited EI values of 3.55%, 2.09%, 2.51%, and 3.64%, respectively. CONCLUSIONS: LPLN metastases was a malignant factor for the prognosis of patients with Siewert type II and III AEG. For patients with preoperative CEA ( +), pT4 stage, HER-2 ( +), and the distance from the EGJ to the distal end of the tumor (> 4.0 cm), TG with LPLN dissection is prioritized for clinical recommendation.


Asunto(s)
Adenocarcinoma , Neoplasias Esofágicas , Unión Esofagogástrica , Gastrectomía , Escisión del Ganglio Linfático , Metástasis Linfática , Neoplasias Gástricas , Humanos , Unión Esofagogástrica/patología , Adenocarcinoma/cirugía , Adenocarcinoma/patología , Masculino , Femenino , Estudios Retrospectivos , Persona de Mediana Edad , Neoplasias Gástricas/patología , Neoplasias Gástricas/cirugía , Factores de Riesgo , Gastrectomía/métodos , Anciano , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/cirugía , Adulto , Ganglios Linfáticos/patología , Relevancia Clínica
6.
BMC Surg ; 24(1): 150, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38745222

RESUMEN

PURPOSE: To investigate whether the mixed approach is a safe and advantageous way to operate laparoscopic right hemicolectomy. METHODS: A retrospective study was performed on 316 patients who underwent laparoscopic right hemicolectomy in our center. They were assigned to the middle approach group (n = 158) and the mixed approach group (n = 158) according to the surgical approaches. The baseline data like gender、age and body mass index as well as the intraoperative and postoperative conditions including operation time, blood loss, postoperative hospital stay and complications were analyzed. RESULTS: There were no significant differences in age, sex, BMI, ASA grade and tumor characteristics between the two groups. Compared with the middle approach group, the mixed approach group was significantly lower in terms of operation time (217.61 min vs 154.31 min, p < 0.001), intraoperative blood loss (73.8 ml vs 37.97 ml, p < 0.001) and postoperative drainage volume. There was no significant difference in the postoperative complications like postoperative anastomotic leakage, postoperative infection and postoperative intestinal obstruction. CONCLUSIONS: Compared with the middle approach, the mixed approach is a safe and advantageous way that can significantly shorten the operation time, reduce intraoperative bleeding and postoperative drainage volume, and does not prolong the length of hospital stay or increase the morbidity postoperative complications.


Asunto(s)
Colectomía , Neoplasias del Colon , Laparoscopía , Tempo Operativo , Complicaciones Posoperatorias , Humanos , Estudios Retrospectivos , Colectomía/métodos , Masculino , Femenino , Laparoscopía/métodos , Neoplasias del Colon/cirugía , Persona de Mediana Edad , Anciano , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Tiempo de Internación/estadística & datos numéricos , Resultado del Tratamiento , Pérdida de Sangre Quirúrgica/estadística & datos numéricos , Adulto
7.
Chem Commun (Camb) ; 60(40): 5334-5337, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38668748

RESUMEN

A photoredox-catalyzed alkylarylation of activated alkenes via a radical C-C bond cleavage/Truce-Smiles rearrangement cascade is developed. The protocol features mild and redox-neutral conditions, broad substrate scope and excellent functional group compatibility, providing a facile and efficient approach to the long-chain distal keto-amides with all-carbon quaternary centers at the alpha position.

8.
Bioresour Technol ; 398: 130521, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38432547

RESUMEN

Wastewater resource recovery not only allows the extraction of value-added products and offsets the operational costs of wastewater treatment, but it is also conducive to alleviating adverse environmental issues due to energy and chemical inputs and associated emissions. A number of attractive compounds such as alginate-like polymers, struvite, polyhydroxyalkanoates, and sulfated polysaccharides, were found and successfully obtained from wastewater and have a wide range of application prospects. The aim of this work is to provide a comprehensive review of recent advances in recovery of these popular products from wastewater, and their physicochemical properties, main sources, and current recovery status are summarized. Various factors influencing the recovery performance of these materials are thoroughly discussed. Moreover, the research needs and future directions towards wastewater resource recovery are highlighted. This study can provide valuable insights for future research endeavors aiming to improve wastewater resource recovery through the retrieval of high value-added products.


Asunto(s)
Polihidroxialcanoatos , Aguas Residuales , Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Polisacáridos
9.
Org Lett ; 26(11): 2266-2270, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38451860

RESUMEN

A sustainable, cyanide-free synthesis of alkyl nitriles via the aerobic oxidative deconstruction of unstrained cycloalkanones with ammonium salts has been developed. Using inexpensive and stable ammonium salts as the nitrogen source, a variety of alkyl nitriles containing a distal carbonyl group were obtained in good yields under visible-light-promoted iron catalysis. This protocol is characterized by mild conditions, abundant and environmentally benign materials, and high atom and step economy with minimal waste generation. The primary mechanism study revealed that 1O2 is likely to be involved in this reaction.

10.
Water Res ; 251: 121163, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38266438

RESUMEN

Arsenic (As) is a toxic metalloid that causes severe environmental contamination worldwide. Upon exposure to aqueous phases, the As-bearing minerals, such as orpiment (As2S3) and realgar (As4S4), undergo oxidative dissolution, in which biotic and abiotic activities both contributed significant roles. Consequently, the dissolved As and S are rapidly discharged through water transportation to broader regions and contaminate surrounding areas, especially in aquatic environments. Despite both orpiment and realgar are frequently encountered in carbonate-hosted neutral environments, the microbial-mediated oxidative dissolution of these minerals, however, have been primarily investigated under acidic conditions. Therefore, the current study aimed to elucidate microbial-mediated oxidative dissolution under neutral aquatic conditions. The current study demonstrated that the dissolution of orpiment and realgar is synergistically regulated by abiotic (i.e., specific surface area (SSA) of the mineral) and biotic (i.e., microbial oxidation) factors. The initial dissolution of As(III) and S2- from minerals is abiotically impacted by SSA, while the microbial oxidation of As(III) and S2- accelerated the overall dissolution rates of orpiment and realgar. In As-contaminated environments, members of Thiobacillus and Rhizobium were identified as the major populations that mediated oxidative dissolution of orpiment and realgar by DNA-stable isotope probing. This study provides novel insights regarding the microbial-mediated oxidative dissolution process of orpiment and realgar under neutral conditions.


Asunto(s)
Arsénico , Arsenicales , Sulfuros , Minerales , Estrés Oxidativo
11.
Sci Total Environ ; 912: 168986, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38040359

RESUMEN

Microplastics (MPs) are emerging pollutants that have been globally found in the environment, and have become a focus of intensive management for the Shanghai government in China. Although there are several studies reporting the abundance of microplastics (MPs) in different matrices in Shanghai city, the general data are still limited. This work comprehensively reviews microplastic (MP) pollution in the water, sediment, atmosphere, and soil of Shanghai during 2013-2022. A summary of characteristics such as the abundance, shape, and polymer composition of MPs is presented. Additionally, the pollution trends, traceability, and ecological risks of MPs are analyzed and evaluated. Based on the analytical results, we find that the inland water in Shanghai city is the most contaminated with the highest abundance of MPs at 14.76 × 103 particles/m3 on average, while the abundances of MPs in the external water, inland sediment, external sediment, indoor atmosphere, outdoor atmosphere, inland soil, and external soil are 2.78 × 103 particles/m3, 0.80 × 103 particles/kg, 1.37 × 103 particles/kg, 0.03 × 103 particles/m3, 0.08 × 103 particles/m3, 0.27 × 103 particles/kg, and 0.18 × 103 particles/kg, respectively. Polyethylene and polypropylene are the top two detected polymer compositions of MPs. Results of ecological risk assessment using risk index and pollution load index models indicate that the risks of MPs in the water and sediment of the Yangtze Estuary are high. It is noteworthy that the abundances of MPs at the junction site of Suzhou Creek and the Huangpu River as well as in the Yangtze Estuary exhibited an increasing trend between 2017 and 2019. This work contributes to a comprehensive overview of MPs in the environment of Shanghai city during 2013-2022 and provides important data for local governments to develop urgent strategies for the management of MP pollution. However, more investigations are increasingly needed for better understand the production, migration, ecological risk, and management of MPs in the environment of Shanghai city.

13.
J Org Chem ; 88(14): 9927-9940, 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37432753

RESUMEN

An array of redox-neutral alkylation/cyclization cascade reactions of N-functionalized acrylamides with cycloalkyl hydroperoxides were achieved via the alkoxyl radical-triggered C-C bond cleavage. Through adjusting the radical acceptors on the N atom, a variety of keto-alkylated chain-containing azaheterocycles, including indolo[2,1-a]isoquinolin-6(5H)-ones, quinoline-2,4-diones, and pyrido[4,3,2-gh]phenanthridines were constructed by a one-pot procedure with good yields and excellent functional group tolerance.

14.
Cell Death Dis ; 14(7): 425, 2023 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-37443102

RESUMEN

Estrogen plays a protective role in colorectal cancer (CRC) and primarily functions through estrogen receptor ß (ERß). However, clinical strategies for CRC therapy associated with ERß are still under investigation. Our discoveries identified WFDC3 as a tumor suppressor that facilitates estrogen-induced inhibition of metastasis through the ERß/TGFBR1 signaling axis. WFDC3 interacts with ERß and increases its protein stability by inhibiting its proteasome-dependent degradation. WFDC3 represses TGFBR1 expression through ERß-mediated transcription. Blocking TGFß signaling with galunisertib, a drug used in clinical trials that targets TGFBR1, impaired the migration of CRC cells induced by WFDC3 depletion. Moreover, there was clinical significance to WFDC3 in CRC, as CRC patients with high WFDC3 expression in tumor cells had favorable prognoses. Therefore, this work suggests that WFDC3 could be an indicator for therapies targeting the estrogen/ERß pathway in CRC patients.


Asunto(s)
Neoplasias Colorrectales , Receptor beta de Estrógeno , Humanos , Receptor beta de Estrógeno/genética , Receptor beta de Estrógeno/metabolismo , Receptor Tipo I de Factor de Crecimiento Transformador beta/genética , Expresión Génica , Estrógenos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Línea Celular Tumoral
15.
J Hazard Mater ; 459: 132172, 2023 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-37523963

RESUMEN

Fluorinated compounds are a class of organic substances resistant to degradation. Although zero-valent iron (Fe0) has a promising reducing capability, it still fails to degrade fluorine-containing antibiotics (i.e., florfenicol) efficiently. In this study, we applied a simple one-pot pyrolytic approach to synthesize nitrogen-doped biochar supported Fe0 and zero-valent copper (Cu0) composite (Fe/Cu@NBC) and investigated its performance on florfenicol removal. The results clearly showed that approximately 91.4% of florfenicol in the deionized water was removed by Fe/Cu@NBC within 8 h. As the reaction time was extended to 15 d, the total degradation rate of florfenicol reached 96.6%, in which the defluorination and dechlorination rates were 73.2% and 82.1%, respectively. Both experimental results and density functional theory calculation suggested that ∙OH and ·O2- triggered ß-fluorine elimination, resulting in defluorination prior to dechlorination. This new finding was distinct from previous viewpoints that defluorination was more difficult to occur than dechlorination. Fe/Cu@NBC also had a favorable performance for removal of florfenicol in surface water. This study provides a new insight into the degradation mechanism and pathway of florfenicol removal in the Fe/Cu@NBC system, which can be a promising alternative for remediation of fluorinated organic compounds in the environment.


Asunto(s)
Antibacterianos , Contaminantes Químicos del Agua , Hierro , Cobre , Nitrógeno , Flúor , Agua , Contaminantes Químicos del Agua/análisis
16.
Environ Sci Pollut Res Int ; 30(35): 84254-84266, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37365358

RESUMEN

Toilet paper has been reported as one of the major insoluble pollutant components in the influent of wastewater treatment plants. Toilet paper fibers contribute to a large production of sewage sludge, resulting in a high treatment cost and high energy consumption. To find energy-efficient, cost-effective, and environment-friendly technologies for fiber removal and resource recovery from wastewater, a life-cycle assessment (LCA) was performed to analyze the wastewater treatment processes, including a sieving process for removing and recovering suspended solids before the biodegradation units. Based on the LCA results, it was estimated that the sieve screening process saved 8.57% of energy consumption. The construction phase of sieving consumed 1.31% energy cost compared with the operation phase. Environmental impact analysis showed that sieving reduced the impacts of climate change, human toxicity, fossil depletion, and particulate matter formation, which reduced the total normalized environmental impacts by 9.46%. The life-cycle analysis of the removal of toilet paper fibers from wastewater revealed the need to use more efficient methods to enhance the recovery of cellulose fibers.


Asunto(s)
Aparatos Sanitarios , Aguas Residuales , Humanos , Animales , Eliminación de Residuos Líquidos/métodos , Aguas del Alcantarillado , Biodegradación Ambiental , Estadios del Ciclo de Vida
17.
Front Oncol ; 13: 1167912, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37064127

RESUMEN

Background: The axillary lymph node positive (ypN+) rate in patients with clinically node-negative (cN0) breast cancer who have achieved breast pathologic complete response (bpCR) after neoadjuvant systemic therapy (NST) is extremely low, and this population has the potential to be exempt from sentinel lymph node biopsy (SLNB). However, an overview of the ypN+ rate in this population for different breast cancer subtypes is lacking. Objective: To provide the pooled ypN+ rate in cN0 patients who achieved bpCR after NST in different breast cancer subtypes defined by hormone receptor (HR) status and human epidermal growth factor receptor 2 (HER2) status. Methods: A systematic literature search was conducted in Embase and PubMed on July 20, 2022. Two authors independently selected studies that met the inclusion criteria and extracted all data. The pooled ypN+ rates for each subtype were calculated by a random-effects model using the Stata 16.0 metaprop command. Results: The pooled analysis of 9609 cN0 patients who achieved bpCR showed that the ypN+ rate was lowest for the HR+/HER2+ (0%) subtype, followed by HR+/HER2- (5.1%), HR-/HER2+ (0.6%), and HR-/HER2- (0.3%). Additionally, 6571 cT1-T2N0 patients who achieved bpCR had a pooled ypN+ rate of 0.6%, and the ypN+ rates for different subtypes were as follows: HR+/HER2+ (1.7%), HR+/HER2- (2.7%), HR-/HER2+ (0.1%), and HR-/HER2- (0.8%). Conclusion: Our results suggested that cN0 patients who achieve bpCR may be exempt from axillary surgery in the HR+/HER2-, HR+/HER2+, and HR-/HER2- subtypes because of the extremely low probability of residual axillary lymph node disease. However, the safety of omitting axillary surgery needs to be further confirmed by prospective studies. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/#recordDetails, identifier CRD42022351739.

18.
Angew Chem Int Ed Engl ; 62(23): e202302835, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37042428

RESUMEN

Both organic radicals and organoboron reagents have been broadly investigated, but the combination of them via direct C-H borylation as organic radical building blocks has never been achieved. Herein, a series of organoradical boron reagents, such as TTM-Bpin and TTM-BOH, were synthesized through the key step of C-H borylation of substrate TTM-H ((2,6-dichlorophenyl) bis(2,4,6-trichlorophenyl)methyl) radical for the first time. They are air stable enough to be stored in the solid state for several months under dark conditions, and fully investigated through single crystal analysis, EPR and DFT calculations. Furthermore, they can smoothly work in the standard Suzuki-Miyaura coupling (SMC) reaction with retention of the carbon radical center. Meanwhile, these radical species bearing different boron units display fluorescent character and are potentially applied for the collective synthesis of luminescent organic radicals, as well as other functionalized open-shell materials.

19.
J Org Chem ; 88(6): 3787-3793, 2023 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-36827360

RESUMEN

Fluorinated compounds have found widespread applications in pharmaceuticals, agrochemicals, and materials science. Precise construction of α-difluoromethylene ether (CF2-O) moiety in organic molecules is of high demand. Herein, a visible light-promoted reaction protocol for the synthesis of α-difluoromethylene ether from gem-difluorocyclopropane is described. The key ring-opening step is induced by hyperconjugative interaction of cyclopropane with photo-oxidized aromatic rings. This reaction is easy scale-up, and the products bearing a synthetic handle enable their further manipulation.

20.
Org Lett ; 25(8): 1336-1341, 2023 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-36815835

RESUMEN

A concise Fe-catalyzed alkylazidation of α-trifluoromethylalkenes via a C-C bond cleavage/radical addition/azidation cascade is described. This protocol features a broad substrate scope, excellent functional group compatibility, and the ability to be performed on a gram scale, thus offering a practical and step-economic approach to the synthetically useful tertiary α-trifluoromethyl azides.

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