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1.
Plants (Basel) ; 13(8)2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38674462

RESUMEN

Aytoniaceae are one of the largest families of complex thalloid liverworts (Marchantiopsida), consisting of about 70 species, with most species being distributed in temperate areas. However, the phylogeny and evolution of the morphological character of Aytoniaceae are still poorly understood. Here, we employed two chloroplast loci, specifically, rbcL and trnL-F, along with a 26S nuclear ribosomal sequence to reconstruct the phylogeny and track the morphological evolution of Aytoniaceae. Our results reveal that Aytoniaceae are monophyletic, and five monophyletic clades were recovered (i.e., Asterellopsis-Cryptomitrium, Calasterella, Mannia, Reboulia-Plagiochasma, and Asterella). Asterella was divided into five clades (i.e., Asterella lindenbergiana, subg. Saccatae, subg. Phragmoblepharis, subg. Wallichianae, and subg. Asterella), except for Asterella palmeri, which is the sister of Asterellopsis grollei. Bayesian molecular clock dating indicates that the five primary clades within Aytoniaceae underwent divergence events in the Cretaceous period. Asterellopsis differentiated during the early Upper Cretaceous (c. 84.2 Ma), and Calasterella originated from the late Lower Cretaceous (c. 143.0 Ma). The ancestral Aytoniaceae plant is reconstructed as the absence of a pseudoperianth, lacking equatorial apertures, and having both male and female reproductive organs on the main thallus. At present, Asterellopsis consists of two species known in Asia and America with the new transfer of Asterella palmeri to Asterellopsis. A new subgenus, Asterella subg. Lindenbergianae, is proposed.

3.
Ground Water ; 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38465736

RESUMEN

The safe operation of underground reservoirs and environmental protection heavily rely on the water flow through coal pillar dams in coal mines. Meanwhile, research on the flow characteristics in coal pillar dams has been limited due to their low hydraulic conductivity. To address this gap, this study assembled a novel seepage experimental device and conducted a series of carefully designed seepage experiments to examine the characteristics of low-permeability in coal pillar dams. The experiments aim to explore the relationship between water flux and hydraulic gradient, considering varying core lengths and immersion times. Flow parameters were determined by fitting observed flux-gradient curves with predictions from both Darcy and non-Darcian laws. Several significant results were obtained. First, a noticeable non-linear relationship between water flux and hydraulic gradient was observed, particularly evident at low flow velocities. Second, the non-Darcy laws effectively interpreted the experimental data, with threshold pressure gradients ranging 13.60 to 58.64 for different core lengths. Third, the study established that water immersion significantly affects the flow characteristics of coal pillar dams, resulting in an increased hydraulic conductivity and flow velocity. These findings carry significant implications for the design of coal pillar dams within underground coal mine reservoirs, providing insights for constructing more stable structures and ensuring environmental protection.

5.
Ann Surg Oncol ; 31(5): 3086, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38319517

RESUMEN

BACKGROUND: Hepatectomy combined with hepatic artery reconstruction in the operation for hilar cholangiocarcinoma (Klatskin tumor) is a challenging procedure. We present a video of left hepatectomy combined with right hepatic artery reconstruction for hilar cholangiocarcinoma. PATIENT AND METHODS: The patient was a 60-year-old male who presented with obstructive jaundice. The imaging examination showed that the confluence of left and right hepatic ducts and the wall of common hepatic duct were thickened, the local lumen was narrowed, the intrahepatic bile duct was dilated, and the right hepatic artery was invaded by tumors nearly 2.3 centimeters. Left hepatectomy with total caudate lobectomy, resection with reconstruction of right hepatic artery, hilar lymphadenectomy, and Roux-en-Y hepaticojejunostomy were performed. RESULTS: The operation time was 345 min, and the amount of bleeding was about 400 ml. There was no blood transfusion. The pathology showed poorly differentiated adenocarcinoma, with negative margins of common bile duct and right hepatic duct, and negative results of all lymph nodes. The patient's recovery was uneventful and he was discharged on postoperative day 14. The patient was disease free at 12-month follow-up evaluation. CONCLUSIONS: Hepatic artery resection and reconstruction procedure is safe and feasible for hilar cholangiocarcinoma in a highly tertiary hepatobiliary center.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Tumor de Klatskin , Masculino , Humanos , Persona de Mediana Edad , Tumor de Klatskin/cirugía , Tumor de Klatskin/patología , Hepatectomía/métodos , Arteria Hepática/cirugía , Arteria Hepática/patología , Hígado/cirugía , Neoplasias de los Conductos Biliares/cirugía , Neoplasias de los Conductos Biliares/patología , Colangiocarcinoma/cirugía
6.
Nutrients ; 16(3)2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38337739

RESUMEN

OBJECTIVES: This study aims to examine the relationship between dietary inflammatory index (DII) and bone mineral density (BMD) changes among Chinese pregnant women, offering valuable insights for dietary guidance during pregnancy. METHODS: 289 pregnant women were enrolled in this cohort. Serum inflammatory factors and ultrasonic BMD were measured at the first, second, and the third trimesters. DII scores were calculated based on a semi-quantitative food frequency questionnaire (FFQ) and divided into tertiles. We compared the differences in inflammatory factors in serum across the tertiles of DII and changes in BMD at the second and third trimesters across the tertiles. RESULTS: The participants with higher DII scores had higher total energy intakes than those with lower DII scores. The serum level of interleukin-6 (IL-6) was significantly different across the tertiles of the DII. Women who had lower DII scores had higher T-scores and Z-scores in the BMD assessment. In the test of trends, after adjusting potential covariates, including educational level, physical activity, body mass index, and calcium, vitamin D, or multivitamin supplements, DII values were determined to be positively related to the maternal BMD lost. CONCLUSIONS: DII was positively associated with serum IL-6. Meanwhile, higher DII scores were associated with more bone mass loss in pregnant women. We recommend adhering to a lower-DII diet to preserve BMD during pregnancy.


Asunto(s)
Densidad Ósea , Mujeres Embarazadas , Humanos , Femenino , Embarazo , Estudios Prospectivos , Interleucina-6 , Dieta , Inflamación
7.
J Minim Access Surg ; 20(2): 148-153, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36695237

RESUMEN

BACKGROUND: Incidental gall bladder cancer (IGBC) is often discovered unexpectedly in patients after cholecystectomy. Currently, magnetic resonance imaging (MRI) has been widely applied in the pre-operative diagnosis of gall bladder diseases as laparoscopic cholecystectomy developed into the preferred method. AIMS AND OBJECTIVES: This study aimed to evaluate the pre-operative MRI application and laparoscopic management in the IGBCs. MATERIALS AND METHODS: Between January 2011 and January 2020, a total of 7917 patients with gall bladder diseases treated by laparoscopy were enrolled in this study. RESULTS: Amongst 49 patients diagnosed with IGBCs, the incidence of IGBCs in polypoid lesions, biliary pancreatitis, cholecystitis, cholecystocholedocholithiasis and gall bladder stones was 0.42%, 1.19%, 0.62%, 1.20% and 0.49%, respectively. MRI evaluation showed more remarkable pre-operative imaging as compared to ultrasonographic evaluation (40.8 vs. 26.5, P < 0.05). Furthermore, 14 patients were diagnosed with gall bladder cancer through intraoperative histological examination and 11 received laparoscopic extensive resection after cholecystectomy. MRI findings with diffuse thickening of the gall bladder detected IGBCs with 6.1% sensitivity, 96.02 specificity, 0.95% positive predictive values and 99.4% negative predictive values; diffuse thickening of the gall bladder with suspicion of malignancy detected IGBCs with 12.2% sensitivity, 99.1% specificity, 7.6% positive predictive values and 99.5% negative predictive values; focal thickening of the gall bladder detected IGBCs with 16% sensitivity, 99.8% specificity, 32% positive predictive values and 99.5% negative predictive values; moreover, suspicious lesion detected IGBCs with 6.1% sensitivity, 99.6% specificity, 8.8% positive predictive values and 99.4% negative predictive values. CONCLUSIONS: Patients with biliary pancreatitis and cholecystocholedocholithiasis have a higher incidence of IGBC. MRI evaluation could provide more accurate information for the IGBCs, which should be recommended for patients accepting cholecystectomy. MRI findings exhibited an unsatisfactory sensitivity when detecting IGBCs, but they represented high specificity. Pre-operative MRI evaluation and intraoperative histological examination may help some IGBCs to achieve one-stage laparoscopic extensive resection.

8.
J Hazard Mater ; 465: 133046, 2024 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-38035527

RESUMEN

Aniline has become a common groundwater contaminant due to its wide use as a raw material in agriculture and pharmaceutical products. The current technologies for in situ remediation of aniline in groundwater are limited by the strains deficient in bacterial species, limited oxygen supply, excessive waste gas load and cost. Accordingly, we conducted a laboratory sand tank experiment to remediate groundwater contaminated with aniline by combining circulated groundwater electrolysis and in-well Rhizobium borbori, which was isolated from activated sludge. The results of the experiment indicated that the optimum concentration of aniline for Rhizobium borbori is about 5 mg/L, beyond which the maximum cell density and the highest specific growth rate decreases as the aniline concentration increases. The optimized duration for immobilizing the Rhizobium borbori into the bioreactor is 4-5 days. Though the Rhizobium borbori was strongly inhibited by the high-concentration of aniline, the immobilized bioreactor in the 350 mg/L aniline solution successfully formed biofilm. The aniline volatilization had limited influence on the observation of bioremediation performance, and the combination of circulated groundwater and in-well Rhizobium borbori supplied a steady dose of oxygen to the bioreactor efficiently degrading the entire region between the injection and extraction well. In addition, a numerical model for the sand tank remediation experiment was used to estimate the yield coefficient of oxygen to be 0.484 g/g, which indicates the presence of ammonia nitrogen as by-products; accordingly, a smaller wellbore size as well a higher circulation flow rate and intensity of current are recommended to improve the water quality. Despite the positive outcomes and potential of the newly developed technology to degrade subsurface aniline, parallel experiments should be conducted to estimate the environmental risk of the by-products and explore the controlling mechanisms of each component in this comprehensive system.


Asunto(s)
Restauración y Remediación Ambiental , Agua Subterránea , Rhizobium , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Arena , Agua Subterránea/microbiología , Compuestos de Anilina/metabolismo , Oxígeno
9.
Clin Nutr ; 43(1): 84-94, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38016243

RESUMEN

BACKGROUND: Sarcopenia is associated with poor outcomes in patients with cirrhosis. However, the prevalence of and associated factors for developing sarcopenia in this population remain to be determined. OBJECTIVES: This study aimed to summarize the prevalence, characteristics, and associated factors of sarcopenia in patients with cirrhosis. METHODS: Electronic searches were performed from inception to June 9, 2022 to identify the eligible studies. We meta-analyzed the prevalence of sarcopenia in overall patients with cirrhosis and subgroups. Both crude and adjusted odds ratios (ORs) were pooled using the random effects model. RESULTS: A total of 55 studies involving 13,158 patients from 17 countries were included. The overall prevalence of sarcopenia was 40.1 % (95 % CI 35.4%-44.9 %) in patients with cirrhosis. The pooled prevalence was higher in males, Child-Pugh class C cirrhosis, decompensated stage, ascites, subjective global assessment class C cirrhosis, and when sarcopenia was defined by L3-SMI (third lumbar-skeletal muscle index) at a higher cutoff. In multivariate analysis, older age (adjusted OR 1.04, 95 % CI 1.00-1.07), male (adjusted OR 4.75, 95 % CI 2.72-8.28), lower body mass index (BMI) (adjusted OR 0.78, 95 % CI 0.73-0.83), alcoholic liver disease (ALD) (adjusted OR 1.43, 95 % CI 1.19-1.72), but not ascites and hepatic encephalopathy, were significantly associated with an increased risk of sarcopenia in patients with cirrhosis. CONCLUSION: Sarcopenia is a prevalent complication, and older age, male patients, lower BMI, and patients with ALD are associated with an increased risk of sarcopenia in patients with cirrhosis.


Asunto(s)
Sarcopenia , Humanos , Masculino , Sarcopenia/etiología , Sarcopenia/complicaciones , Prevalencia , Cirrosis Hepática/complicaciones , Cirrosis Hepática/epidemiología , Músculo Esquelético , Fibrosis , Ascitis
10.
bioRxiv ; 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37873099

RESUMEN

Controllable assembly of cells and tissues offers potential for advancing disease and development modeling and regenerative medicine. The body's natural scaffolding material is the extracellular matrix, composed largely of collagen I. However, challenges in precisely controlling collagen assembly limit collagen's applicability as a primary bioink or glue for biofabrication. Here, we introduce a set of biopatterning methods, termed Tunable Rapid Assembly of Collagenous Elements (TRACE), that enables instant gelation and rapid patterning of collagen I solutions with wide range of concentrations. Our methods are based on accelerating the gelation of collagen solutions to instantaneous speeds via macromolecular crowding, allowing versatile patterning of both cell-free and cell-laden collagen-based bioinks. We demonstrate notable applications, including macroscopic organoid engineering, rapid free-form 3D bioprinting, contractile cardiac ventricle model, and patterning of high-resolution (below 5 (m) collagen filament. Our findings enable more controllable and versatile applications for multi-scale collagen-based biofabrication.

11.
bioRxiv ; 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37873466

RESUMEN

During development and disease progression, cells are subject to osmotic and mechanical stresses that modulate cell volume, which fundamentally influences cell homeostasis and has been linked to a variety of cellular functions. It is not well understood how the mechanobiological state of cells is programmed by the interplay of intracellular organization and complex extracellular mechanics when stimulated by cell volume modulation. Here, by controlling cell volume via osmotic pressure, we evaluate physical phenotypes (including cell shape, morphodynamics, traction force, and extracellular matrix (ECM) remodeling) and molecular signaling (YAP), and we uncover fundamental transitions in active biophysical states. We demonstrate that volumetric compression shifts the ratiometric balance of Rho GTPase activities, thereby altering mechanosensing and cytoskeletal organization in a reversible manner. Specifically, volumetric compression controls cell spreading, adhesion formation, and YAP nuclear translocation, while maintaining cell contractile activity. Furthermore, we show that on physiologically relevant fibrillar collagen I matrices, which are highly non-elastic, cells exhibit additional modes of cell volume-dependent mechanosensing that are not observable on elastic substrates. Notably, volumetric compression regulates the dynamics of cell-ECM interactions and irreversible ECM remodeling via Rac-directed protrusion dynamics, at both the single-cell level and the multicellular level. Our findings support that cell volume is a master biophysical regulator and reveal its roles in cell mechanical state transition, cell-ECM interactions, and biophysical tissue programming.

12.
Opt Express ; 31(20): 33732-33740, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37859146

RESUMEN

Atomic layer deposited Al2O3 films are incorporated into miniature light emitting diodes (mini-LEDs) as an internal moisture barrier layer. The experimental results show that the water vapor transmission rate reaches ≤10-4 g/m2/day when the Al2O3 thickness is ≥40 nm. The mini-LED with a 40 nm-thick Al2O3 layer shows negligible degradation after 1000 h of 85°C/85% relative humidity testing, whereas the device without an Al2O3 layer fails after only 500 h due to delamination occurring at the GaN surface. Current-voltage characteristics of the device without an Al2O3 moisture barrier layer indicate an increase in series resistance and ideality factor. This study provides a simple, light-weighting method to have a satisfactory encapsulation function for miniature LEDs.

13.
Ground Water ; 61(6): 895-913, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37776229

RESUMEN

The Maocun underground karst river system in the peak cluster depression is an important source of groundwater in southwest China. Multitracers and high resolution water-level-monitoring technology were used to assess and evaluate the hydrogeological structure and flow dynamics. The results showed that the spatial geological structures of the sites had high heterogeneity. Scatter plots of environmental tracers divided the sampling points into groups under different water flow patterns. The karstification was found to increase from sites XLB and LLS to sites BY, SGY and BDP to sites CY and DYQ, where the main water flow patterns at these site groups were diffuse water, both diffuse water and conduit water, and conduit water, respectively. The response times of the subsystems were found to be influenced by the spatial structure, the degree of karstification, and the volume of precipitation and frequency. The average response times of SGY, BDP, ZK, and Outlet in the selected precipitation scenarios were 5.17, 4.08, 16.42, and 5.83 h, respectively. In addition, the EC, δ13 CDIC , 222 Rn, and δ18 O exhibited both linear or exponential relationships. Overall, three hydrogeological conceptual models were constructed showing: (1) high precipitation driving the deep water, resulting in a concentrated flow regime and regional groundwater flow field; (2) both concentrated and diffuse water flows existing under moderate precipitation, resulting in mixed water flow field; (3) the water cycle in the shallow karst aquifer system under low precipitation causing the local groundwater flow field to be dominated by diffuse water flow.


Asunto(s)
Agua Subterránea , Contaminantes Químicos del Agua , Monitoreo del Ambiente/métodos , Agua Subterránea/química , Ríos/química , China , Agua , Contaminantes Químicos del Agua/análisis
14.
Proc Natl Acad Sci U S A ; 120(39): e2220062120, 2023 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-37722033

RESUMEN

Physical forces are prominent during tumor progression. However, it is still unclear how they impact and drive the diverse phenotypes found in cancer. Here, we apply an integrative approach to investigate the impact of compression on melanoma cells. We apply bioinformatics to screen for the most significant compression-induced transcriptomic changes and investigate phenotypic responses. We show that compression-induced transcriptomic changes are associated with both improvement and worsening of patient prognoses. Phenotypically, volumetric compression inhibits cell proliferation and cell migration. It also induces organelle stress and intracellular oxidative stress and increases pigmentation in malignant melanoma cells and normal human melanocytes. Finally, cells that have undergone compression become more resistant to cisplatin treatment. Our findings indicate that volumetric compression is a double-edged sword for melanoma progression and drives tumor evolution.


Asunto(s)
Melanoma , Transcriptoma , Humanos , Melanoma/genética , Perfilación de la Expresión Génica , Melanocitos , Fenotipo
15.
J Tradit Chin Med ; 43(5): 1010-1018, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37679989

RESUMEN

OBJECTIVE: To evaluate the efficacy and safety of Buzhong Yiqi decoction (, BZYQ) in the treatment of hospital-acquired pneumonia (HAP) with multi-drug-resistant bacteria (MDRB). METHODS: This 28-day study was conducted at 5 clinical centers in Shanghai. The eligible patients were randomly assigned (1:1) into the intervention group (BZYQ plus conventional Western Medicine therapy) and control group (conventional Western Medicine therapy). The primary outcomes were the clinical response, clinical pulmonary infection score (CPIS), and microbiologic response. The secondary outcomes were the 28-day all-cause mortality (ACM), Acute Physiology and Chronic Health Evaluation Ⅱ (APACHE Ⅱ) score, ventilator weaning rate, length of mechanical ventilation (MV), length of hospital stay, and changes of infection indicators. RESULTS: Altogether 83 subjects in the intervention group and 85 subjects in the control group were analyzed. The clinical success rate (48.2%) and the pathogen eradication rate (59.0%) of the intervention group were all better than those of the control group (32.9% and 38.9%, respectively) with statistically significant differences (<0.05). The CPIS score of the intervention group (8.9 ± 1.7) was lower than that of the control group (9.6 ± 2.5) (<0.05). The length of MV in the intervention group [(13.7 ± 6.4) d] was significantly shorter than that of the control group [ (17.2 ± 7.2) d] (<0.05). The 28-day ACM of the intervention group (13.33%) was lower than that of the control group (21.2%) with no statistically significant difference (>0.05). The differences between two groups in ventilator weaning rate, length of hospital stay, and APACHE Ⅱ score were not statistically significant (> 0.05). The intervention group displayed decreases in white blood cell count, C-reactive protein, neutrophil percentage, and procalcitonin at day 28 compared with baseline (<0.05). No serious adverse events occurred in either group during the 28-day follow-up. CONCLUSION: BZYQ may be an effective therapeutic option for the management of HAP with MDRB.


Asunto(s)
Bacterias , Hospitales , Humanos , Estudios Prospectivos , China , Resultado del Tratamiento , Bacterias/genética
17.
Foods ; 12(15)2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37569205

RESUMEN

Daqu is a traditional starter for Baijiu fermentation and is produced by spontaneous fermentation of ground and moistened barley or wheat. The quality of Daqu is traditionally evaluated based on physicochemical and subjective sensory parameters without microbiological analysis. Here, we compared the physicochemical characteristics of qualified (QD) and inferior (ID) Daqu, their microbial communities based on plate counting and PacBio SMRT sequencing of rRNA gene libraries, and their impacts on Baijiu fermentation. The results showed that the glucoamylase and α-amylase activities of QD were significantly higher than those of ID. The counts of yeasts and relative abundances of functional microbes, especially the amylolytic bacterium Bacillus licheniformis and fungi Saccharomycopsis fibuligera and Lichtheimia ramosa, were significantly higher in QD than in ID. The laboratory-scale Baijiu fermentation tests showed that the relative abundances of the amylolytic microbes were higher in the QD than the ID fermentation set, resulting in more efficient fermentation, as indicated by more weight loss and higher moisture content in the former. Consequently, more glycerol, acetic acid, ethanol, and other volatile compounds were produced in the QD than in the ID fermentation set. The results suggest that Daqu quality is determined by, and can be evaluated based on, its microbial community.

18.
Ground Water ; 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37646611

RESUMEN

The slug test has been commonly used to estimate aquifer parameters. Previous studies on the slug test mainly focused on a single-layer aquifer. However, understanding the interaction between layers is particularly important when assessing aquifer parameters under certain circumstances. In this study, a new semi-analytical model on transient flow in a three-layered aquifer system with a partially penetrating well was developed for the slug test. The proposed model was solved using the Laplace transform method and the Goldstein-Weber transform method, where the semi-analytical solution for the model was obtained. The drawdowns of the proposed model were analyzed to understand the impacts of the different parameters on the drawdowns in a three-layered aquifer system. The results indicated that groundwater interactions between the layers have a significant impact on the slug test. In addition, a shorter and deeper well screen as well as a greater permeability ratio between the layers creates a greater interface flow between them, leading to a higher drawdown in the slug test. Finally, a slug test in a three-layered aquifer system was conducted in our laboratory to validate the new model, which indicated that the proposed model performed better in the interpretation of the experimental data than a previous model proposed by Hyder et al. (1994). We also proposed an empirical relationship to qualitatively identify the errors in the application of single-layer model for the analysis of response data in a three-layered aquifer system.

19.
Chem Commun (Camb) ; 59(60): 9215-9218, 2023 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-37415526

RESUMEN

In this work, 1-aminopropyl-3-methylimidazolium bromide (APMImBr) is introduced in dimethyl sulfoxide-based Li-O2 batteries. The Br- functions as a redox mediator to catalyze the decomposition of the Li2O2 products. Meanwhile, the APMIm+ serves as a scavenging agent for superoxide radicals as well as protects the lithium metal anodes via an in situ formed Li3N-rich solid electrolyte interface layer. As a result, the Li-O2 batteries containing APMImBr delivered an enlarged discharge capacity, a reduced charge overpotential of around 0.61 V and a prolonged cyclic life of over 200 cycles.

20.
J Labelled Comp Radiopharm ; 66(10): 321-331, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37337654

RESUMEN

The direct electrophilic deuteration of the aromatic moiety in aromatic and aralkyl amines is reported. The acid-catalyzed deuteration is facilitated by deuterated trifluoromethanesulfonic acid, [D]triflic acid, CF3 SO3 D, TfOD, which acts as both the reaction solvent and the source of the deuterium label. The mild conditions enable room temperature hydrogen/deuterium exchange for most of the para-substituted aromatic amine derivatives studied. In addition, short reaction times and a high degree of aromatic deuteration are achieved and isolation of the product is simple. The optical activity of the chiral aralkyl amines studied was preserved.


Asunto(s)
Aminas , Hidrógeno , Deuterio , Medición de Intercambio de Deuterio
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