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1.
J Environ Manage ; 335: 117581, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36867901

RESUMO

The rapid increase in electronic waste (e-waste) generation and its unsustainable management pose a threat to the environment and human well-being. However, various valuable metals are present in e-waste, which makes it a potential secondary source to recover metals. Therefore, in the present study, efforts were made to recover valuable metals (Cu, Zn, and Ni) from waste printed circuit boards (WPCB) of computers using methanesulfonic acid (MSA). MSA is contemplated as a biodegradable green solvent and has a high solubility for various metals. The effect of various process parameters (MSA concentration, H2O2 concentration, stirring speed, liquid to solid ratio, time, and temperature) was investigated on metal extraction to optimize the process. At the optimized process conditions, 100% extraction of Cu and Zn was achieved, while Ni extraction was around 90%. The kinetic study for metal extraction was performed using a shrinking core model and findings showed that MSA-aided metal extraction is a diffusion-controlled process. Activation energies were found to be 9.35, 10.89, and 18.86 kJ/mol for Cu, Zn, and Ni extraction, respectively. Furthermore, the individual recovery of Cu and Zn was achieved using the combination of cementation and electrowinning, which resulted in 99.9% purity of Cu and Zn. The current study proposes a sustainable solution for the selective recovery of Cu and Zn from WPCB.


Assuntos
Resíduo Eletrônico , Peróxido de Hidrogênio , Humanos , Metais , Mesilatos , Reciclagem/métodos , Cobre
2.
Drug Deliv Transl Res ; 13(4): 1153-1168, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36585559

RESUMO

Rasagiline mesylate (RM) is a monoamine oxidase inhibitor that is commonly used to alleviate the symptoms of Parkinson's disease. However, it suffers from low oral bioavailability due to its extensive hepatic metabolism in addition to its hydrophilic nature which limits its ability to pass through the blood-brain barrier (BBB) and reach the central nervous system where it exerts its pharmacological effect. Thus, this study aims to form RM-loaded spanlastic vesicles for intranasal (IN) administration to overcome its hepatic metabolism and permit its direct delivery to the brain. RM-loaded spanlastics were prepared using thin film hydration (TFH) and modified spraying technique (MST). A 23 factorial design was constructed to study and optimize the effects of the independent formulation variables, namely, Span type, Span: Brij 35 ratio, and sonication time on the vesiclesá¾½ characteristics in each preparation technique. The optimized system prepared using MST (MST 2) has shown higher desirability factor with smaller PS and higher EE%; thus, it was selected for further in vivo evaluation where it revealed that the extent of RM distribution from the intranasally administered spanlastics to the brain was comparable to that of the IV drug solution with significantly high brain-targeting efficiency (458.47%). These results suggest that the IN administration of the optimized RM-loaded spanlastics could be a promising, non-invasive alternative for the efficient delivery of RM to brain tissues to exert its pharmacological activities without being dissipated to other body organs which subsequently may result in higher pharmacological efficiency and better safety profile.


Assuntos
Encéfalo , Portadores de Fármacos , Portadores de Fármacos/metabolismo , Tamanho da Partícula , Encéfalo/metabolismo , Administração Intranasal , Mesilatos/metabolismo , Mesilatos/farmacologia , Sistemas de Liberação de Medicamentos/métodos
3.
Molecules ; 27(23)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36500695

RESUMO

Polycyclic aromatic sulfur-containing compounds are widely distributed in oil, especially in its low-volatile and heavy fractions (resins, asphaltenes), and this dictates the need for their determination when reliable methods for sulfur removing, cleaning and processing oil are developed. In these cases, "soft" ionization mass spectrometry methods, based on electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI), are particularly effective. However, aromatic sulfur-containing compounds have low polarity and cannot be readily ionized by these methods. To overcome the problem, their preliminary conversion into sulfonium salts by the action of alkyl iodides and a silver-containing agent is widely used. In the process of developing more economical derivatization methods, we found a rather unexpected possibility of implementing S-alkylation of organic sulfides with commercial polydialkylsiloxanes (alkyl = CH3 or C2H5) in the presence of triflic acid (CF3SO3H) as a superacid co-alkylating agent. For homologous dibenzothiophenes as a typical model representative of petroleum sulfur-containing aromatic compounds, ESI and MALDI mass spectra exhibited the signals of corresponding S-alkylsulfonium salts with a high signal-to-noise ratio. A rational mechanism for the described chemical transformation is proposed, including the indispensable activation by triflic acid and the cleavage of the Si-C bond. Specific collision-induced dissociation of corresponding S-alkylated sulfonium cations is considered. The applicability of the derivatization approach to the analysis of petroleum products by high-resolution mass spectrometry is demonstrated.


Assuntos
Petróleo , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Mesilatos , Enxofre , Compostos Orgânicos
4.
Int J Mol Sci ; 23(19)2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36233094

RESUMO

Hybrid nanoarchitectures such as magnetic polymeric micelles (MPMs) are among the most promising nanotechnology-enabled materials for biomedical applications combining the benefits of polymeric micelles and magnetic nanoparticles within a single bioinstructive system. MPMs are formed by the self-assembly of polymer amphiphiles above the critical micelle concentration, generating a colloidal structure with a hydrophobic core and a hydrophilic shell incorporating magnetic particles (MNPs) in one of the segments. MPMs have been investigated most prominently as contrast agents for magnetic resonance imaging (MRI), as heat generators in hyperthermia treatments, and as magnetic-susceptible nanocarriers for the delivery and release of therapeutic agents. The versatility of MPMs constitutes a powerful route to ultrasensitive, precise, and multifunctional diagnostic and therapeutic vehicles for the treatment of a wide range of pathologies. Although MPMs have been significantly explored for MRI and cancer therapy, MPMs are multipurpose functional units, widening their applicability into less expected fields of research such as bioengineering and regenerative medicine. Herein, we aim to review published reports of the last five years about MPMs concerning their structure and fabrication methods as well as their current and foreseen expectations for advanced biomedical applications.


Assuntos
Hipertermia Induzida , Micelas , Meios de Contraste , Sistemas de Liberação de Medicamentos/métodos , Mesilatos , Piperidinas , Polímeros/química , Medicina de Precisão
5.
Biomed Res Int ; 2022: 5482895, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36267841

RESUMO

The current study is aimed at examining the overall effects of steroids on the tissues of organisms and pharmacotherapeutics and pharmaco-histokinetics of several steroids, including Bromocriptine as mesylate and estradiol valerate in common quails (Coturnix coturnix). A total of 100 birds were used for pharmaco-histokinetics. The research was carried out in two separate trials, one during the fall season and the other during the spring season. Each experiment lasted for five, ten, fifteen, and twenty days. Each study group used 20 birds while basing their experiments on a control group of 5. At the stretch of five, ten, fifteen, and twenty days in each season, therapeutic dosages were administered to a sum of two groups representing two separate steroid trial groups. Each steroid was administered to each bird in a therapeutic dose, which was three drops administered twice daily. Clinical symptoms include despondency, sluggishness, and variations in weight and temperature that almost all treated birds display. However, only in trials conducted in the fall was a sizable degree of body enlargement in one treated bird noticed. The winter testing showed a mortality rate. Four birds have died in the twenty-day group. One bird died when treated with estradiol valerate, and three birds died treated with Bromocriptine as mesylate. Both the male and female birds showed signs of having lost some of their body weight. The treated birds' kidney, stomach, hearts, and livers exhibited some edema. In comparison, almost all birds show enteritis, which indicates that steroids mainly affect the intestine. There were apparent differences in the histological analysis of heart and skeletal muscle and some treated birds with the control group. The kidney, liver, and intestine show the major histopathological change in all treated birds.


Assuntos
Bromocriptina , Coturnix , Animais , Feminino , Masculino , Coturnix/fisiologia , Bromocriptina/farmacologia , Estradiol , Mesilatos
6.
Food Funct ; 13(21): 10895-10911, 2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36239175

RESUMO

Many strategies are used to quantify microbial (poly)phenol metabolites (MPMs) in urine. Currently, to obtain accurate results, the use of phase II conjugate analytical standards is deemed to be the gold standard. However, these standards are expensive or commercially unavailable. Quantification using an affordable and commercially available unconjugated analytical standard following hydrolysis with the crude preparation from Helix pomatia containing arylsulfatase and ß-glucuronidase was once considered to be an alternative, but previous studies have shown poor hydrolysis efficiency for conjugated MPMs. In this work, we evaluated the efficiency of purified recombinant enzymes and compared them with the preparation from H. pomatia using 75 urine samples. 38 conjugated MPMs were identified before hydrolysis, associated with 17 unconjugated MPMs. Rapid chemical synthesis of sulfated compounds was carried out to increase the confidence level for the identification of 13 sulfated MPMs. Recombinant enzymes had a mean hydrolysis efficiency of over 95% for 36 out of 38 conjugated MPMs with a hydrolysis time of 30 min. In comparison, the preparation from H. pomatia achieved similar efficiency for only 28 conjugated MPMs after 6 h of hydrolysis. When comparing the concentration of unconjugated MPMs released after enzymatic hydrolysis, recombinant enzymes were more or as effective for almost every MPM. These results demonstrate that accurate quantification of MPMs in urine can be quickly achieved using purified recombinant enzymes and represent an affordable alternative to the use of conjugated analytical standards, improving access to the analysis of the metabolism of (poly)phenols by the gut microbiota.


Assuntos
Mesilatos , Fenol , Piperidinas , Glucuronidase/metabolismo , Hidrólise , Fenóis
7.
Molecules ; 27(19)2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36235187

RESUMO

Ionic liquids (ILs) have emerged as active pharmaceutical ingredients because of their excellent antibacterial and biological activities. Herein, we used the green-chemistry-synthesis procedure, also known as the metathesis method, to develop three series of ionic liquids using 1-methyl-3-butyl imidazolium, butyl pyridinium, and diethyldibutylammonium as cations, and bromide (Br-), methanesulfonate (CH3SO3-), bis(trifluoromethanesulfonyl)imide (NTf2-), dichloroacetate (CHCl2CO2-), tetrafluoroborate (BF4-), and hydrogen sulfate (HSO4-) as anions. Spectroscopic methods were used to validate the structures of the lab-synthesized ILs. We performed an agar well diffusion assay by using pathogenic bacteria that cause various infections (Escherichia coli; Enterobacter aerogenes; Klebsiella pneumoniae; Proteus vulgaris; Pseudomonas aeruginosa; Streptococcus pneumoniae; Streptococcus pyogenes) to scrutinize the in vitro antibacterial activity of the ILs. It was established that the nature and unique combination of the cations and anions were responsible for the antibacterial activity of the ILs. Among the tested ionic liquids, the imidazolium cation and NTf2- and HSO4- anions exhibited the highest antibacterial activity. The antibacterial potential was further investigated by in silico studies, and it was observed that bis(trifluoromethanesulfonyl)imide (NTf2-) containing imidazolium and pyridinium ionic liquids showed the maximum inhibition against the targeted bacterial strains and could be utilized in antibiotics. These antibacterial activities float the ILs as a promising alternative to the existing antibiotics and antiseptics.


Assuntos
Compostos de Amônio , Anti-Infecciosos Locais , Líquidos Iônicos , Ágar , Ânions/química , Antibacterianos/farmacologia , Brometos/química , Dióxido de Carbono , Cátions/química , Escherichia coli , Hidrocarbonetos Fluorados , Hidrogênio , Imidazóis/química , Imidazóis/farmacologia , Imidas , Líquidos Iônicos/química , Líquidos Iônicos/farmacologia , Mesilatos , Preparações Farmacêuticas , Sulfatos
8.
J Prev Alzheimers Dis ; 9(4): 780-790, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36281683

RESUMO

BACKGROUND: Hydromethylthionine mesylate is a tau aggregation inhibitor shown to have exposure-dependent pharmacological activity on cognitive decline and brain atrophy in two completed Phase 3 trials in mild/moderate Alzheimer's disease (AD). OBJECTIVES: The present report summarises the basis for selection of 16 mg/day as monotherapy as the optimal treatment regime and the design rationale of a confirmatory Phase 3 trial (LUCIDITY). DESIGN: The trial comprises a 12-month double-blind, placebo-controlled phase followed by a 12-month modified delayed-start open-label treatment phase. SETTING: 76 clinical research sites in North America and Europe. PARTICIPANTS: 545 patients with probable AD or MCI-AD in the final version of the protocol. INTERVENTION: Participants were assigned randomly to receive hydromethylthione mesylate at doses of 16 mg/day, 8 mg/day or placebo at a 4:1:4 ratio during the double-blind phase. All participants in the open-label phase receive the 16 mg/day dose. MEASUREMENTS: Co-primary clinical outcomes are the 11-item Alzheimer's Disease Assessment Scale (ADAS-cog11) and the 23-item Alzheimer's Disease Cooperative Study - Activities of Daily Living (ADCS-ADL23). Secondary biomarker measures include whole-brain atrophy and temporal lobe 18F-fluorodeoxyglucose positron emission tomography. RESULTS: 446 participants are expected to complete the 12-month placebo-controlled phase in March 2022. CONCLUSIONS: If the primary end points are met, the data will provide confirmatory evidence of the clinical and biomarker benefits of hydromethylthionine mesylate in minimal to moderate AD. As low-dose oral hydromethylthionine mesylate is simple to use clinically, does not cause amyloid-related imaging abnormalities and has a benign safety profile, it would likely improve AD management.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/tratamento farmacológico , Atividades Cotidianas , Fluordesoxiglucose F18 , Atrofia/tratamento farmacológico , Mesilatos/uso terapêutico
9.
Acta Crystallogr C Struct Chem ; 78(Pt 10): 531-541, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36196786

RESUMO

Comprehensive chemical characterization for two isomers of camphorsulfonic acid (CSA), occasionally used in the manufacture of active pharmaceutical ingredients (APIs), was performed by nuclear magnetic resonance (NMR) spectroscopy, high-resolution mass spectroscopy in negative electrospray ionization mode and gas chromatography/mass spectrometry (GC/MS) in electron ionization mode. Electronic circular dichroism (ECD) spectra together with quantum chemical calculations using time-dependent density functional theory (TD-DFT) were used to assign the stereochemistry for CSA for the first time and these assignments were then confirmed by single-crystal X-ray diffraction. As crystals were grown under the same conditions of high supersaturation using a mixed solvent without water removal, the crystal structures of the two enantiomers contained one ordered molecule of water in the asymmetric unit. The crystals of the (+)-enantiomer have a 1S,4R configuration and the H atom of the sulfonic acid group combines with the water molecule to form a hydronium ion, namely, hydronium (1S,4R)-(7,7-dimethyl-2-oxobicyclo[2.2.1]heptan-1-yl)methanesulfonate, H3O+·C10H15O4S-. The crystals of the (-)-enantiomer have a 1R,4S configuration. The determination of the optical purity of CSA using NMR spectroscopy with a chiral solvating agent, (1R,2R)-1,2-diphenylethane-1,2-diamine, and GC/MS with a chiral column has been well explored. The results showed that the examined samples of these two isomers of CSA proved to be enantiomerically pure. In particular, for (1R)-(-)-10-camphorsulfonic acid, this is, to our knowledge, the first description on its spectral characterization in a scientific context.


Assuntos
Mesilatos , Água , Cânfora/análogos & derivados , Cristalografia por Raios X , Diaminas , Ligação de Hidrogênio , Estrutura Molecular , Preparações Farmacêuticas , Solventes , Estereoisomerismo , Ácidos Sulfônicos
10.
Rev. senol. patol. mamar. (Ed. impr.) ; 35(4): 221-227, oct.-dic. 2022. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-211065

RESUMO

Objetivo: analizar la eficacia y la seguridad de la eribulina en la vida real en el tratamiento del cáncer de mama metastásico refractario en un hospital terciario. Métodos: estudio observacional y retrospectivo que incluyó a pacientes con cáncer de mama metastásico (CMm) quienes recibieron eribulina entre el 01/04/2014 y el 31/10/2020. Se analizaron variables demográficas (sexo/edad), del tratamiento quimioterápico (duración, dosis, regímenes previos) y clínicas (sobreexpresión HER2, receptores hormonales, supervivencia libre de progresión [SLP], supervivencia global [SG], toxicidad). La progresión se analizó siguiendo los criterios de RECISTv1.1 y la toxicidad según CTCAE.5.0. Se realizó un análisis estadístico mediante Log-Rank test y regresión de Cox. Resultados: se incluyeron 38 pacientes de 57,6 años (± 11,85) con ECOG PS ≥ 2 (84,2%), sin sobreexpresión HER2 (86,8%) y expresión de receptores hormonales (84,2%). Todas habían fracasado a 2 líneas quimioterápicas. La duración del tratamiento fue de 4,35 meses (2,44–6). El 79% sufrieron retraso en la administración y 60% reducción de la dosis. Se presentaron un 15,8% de eventos de grado 3 y 10,5% grado 4. Fallecieron 32 pacientes con mediana SG 12,4 meses (8,3-16,5) y 37 progresaron con mediana SLP 6 meses (4,85-7,16). Se observaron diferencias significativas para SG en el subgrupo con hormonoterapia previa (tipos luminal A y B) (13,8 meses [9,9–17,6]; HR = 0,34 IC 95% [0,12–0-98]; p = 0,045 frente a 6,5 meses [6,1-6,9]. SLP superior y significativa en el subgrupo con ECOG PS > 2 (6,5 meses [3,65-9,34]; HR = 0,35 IC 95% [00,16-0,75]; p = 0,038 frente a 3,73 [0,09-7,38]). Conclusiones: la eficacia de la eribulina en nuestra práctica asistencial habitual es similar a la obtenida en ensayos clínicos, observándose una mayor SG en las pacientes pretratadas con hormonoterapia y mayor SLP en las pacientes ECOG PS > 2, con menor incidencia de toxicidades grado 3–4. (AU)


Objective: To assess efficacy (progression-free survival (PFS) and overall survival (OS)) and safety of eribulin in real clinical practice. Methods: Observational and retrospective study. Patients with metastatic breast cancer (mBC) treated with eribulin between 01/04/2014 and 31/10/2020 were included. Age, sex, ECOG performance status, HER-2, hormone receptor status, previous regimens for metastatic disease, previous ratio/hormone/surgical therapy, duration of treatment, toxicity and time to progression or death, were collected. Progression was evaluated by RECISTv1.1 criteria and toxicity by CTCAE.5.0 criteria. Statistical analysis was conducted by Log-Rank's test and Cox's Regression. Results: 38 patients were included, median age 57,6 years (±11,85), ECOG PS ≥ 2 (84,2%), negative HER2 overexpression (86,8%), hormone receptors expression (84,2%). All patients had already failed 2 chemotherapy regimens. Median duration was 4,35 months (IQR:2,44–6) and median cycles was 6 (IQR:4–8). Delays or reductions were 79% and 60,5%, respectively. Treatment was generally well tolerated, with 15.8% grade 3 and 10.5% grade 4 toxicities. 32 patients deceased, median OS 12,4 months (8,3-16,5). 37 had progressed, median PFS 6 moths (4,85-7,16). Log-Rank's test showed statistically significant difference in OS in patients with previous hormone therapy confirmed in Cox's regression [median 13,8 months (9.9–17.6); HR = 0,34 CI95%(0,12-0,98); p = 0,045 vs 6,5 months (6,1-6,9)]. ECOG PS > 2 showed better PFS in Log-Rank's Test and Cox's Regression [6,5 months (3,65-9,34); HR:0,35 CI95%(0,16-0,75); p = 0.038 vs 3,73 (0,09-7,38)]. Conclusions: Efficacy of eribulin in our real practice is similar to data from clinical essays observing statistically significant more OS in patients with previous hormone therapy and more PFS in ECOG's PS >2 subgroup and less incidence of grade 3/4-toxicity. (AU)


Assuntos
Humanos , Pessoa de Meia-Idade , Idoso , Neoplasias da Mama/tratamento farmacológico , Mesilatos , Estudos Retrospectivos , Epidemiologia Descritiva , Estudos Longitudinais , Segurança
11.
J Environ Manage ; 322: 116101, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36055102

RESUMO

As the most abundant greenhouse gas, atmospheric carbon dioxide (CO2) is considered one of the main attributors to climate change. Atmospheric CO2 concentrations can be measured by ground-based monitoring networks, mobile monitoring campaigns, and carbon-observing satellites. However, the worldwide ground-based monitoring networks are composed of sparsely distributed sites and are inadequate to represent the spatiotemporal distributions of CO2. Satellite-based remote sensing features repeated, long-term, and large-scale measurements, so it plays a crucial role in monitoring the global distributions of atmospheric CO2. However, due to the presence of heavy clouds (or aerosols) and the limitation of satellite orbiting tracks, there exist large amounts of missing data in satellite retrievals. Various methods, including chemical transport models (CTMs), geostatistical methods, and regression-based models, have been employed to derive full-coverage spatiotemporal distributions of CO2 based on the limited CO2 measurements. This review summarizes the strengths and limitations of these methods. However, CTMs simulation results can have high uncertainty due to imperfect knowledge of the real world, and the interpolation accuracy of all geostatistical methods is limited by the large amount of data gaps in current satellite retrieved CO2 products. To overcome these limitations, regression-based methods (especially machine learning models) have the ability to predict CO2 with superior predictive performance, so this review also summarizes the framework of the machine learning approach. Leveraging the ongoing advancements of satellite instrumentation, the satellite-based CO2 products have been improving dramatically in recent decades, and this review will describe and critically assess the advantages and disadvantages of the currently used systems in detail. For future improvements, we recommend the fusion of data from multiple satellite retrievals and CTMs by using machine learning algorithms in order to obtain even longer-term, larger-scale, finer-resolution, and higher-accuracy CO2 datasets.


Assuntos
Dióxido de Carbono , Gases de Efeito Estufa , Aerossóis/análise , Dióxido de Carbono/análise , Cicloexanos , Monitoramento Ambiental/métodos , Mesilatos
12.
Chem Rev ; 122(18): 14954-14986, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-36112746

RESUMO

Due to their solution processability and unique photoelectric characteristics, perovskite solar cells (PSCs) have shown considerable promise in the area of renewable energy. Although their power conversion efficiency (PCE) has risen from 3.8% to 25.7% in only a few years, their short lifetime and high material prices continue to be key roadblocks to commercial viability. Charge transporting materials (CTMs), such as hole/electron transporting materials, are critical components in PSCs because they not only govern hole or electron extraction and transporting from the perovskite layer to the electrodes but also protect the perovskite from direct contact with the ambient environment. CTMs are split into two types: inorganic CTMs (ICTMs) and organic CTMs (OCTMs). Because of their inexpensive prices, well-adjusted energy levels, and low temperature solution-processed features, OCTMs have been more frequently explored and employed than ICTMs. Various forms of OCTMs with more straightforward synthetic pathways and better performance have been thoroughly researched. Recent achievements in the development of OCTMs will be discussed and evaluated on a molecular level in this study, which will include a systematic categorization of OCTMs based on molecular functionalization techniques. In order to achieve highly efficient and stable PSCs, we will present insights on the structure-property relationship in the design of OCTMs as well as device stability. We hope that this analysis will serve as a comprehensive reference to molecular design guidelines for various types of OCTMs, spurring greater research toward designing highly efficient and OCTMs for stable PSCs.


Assuntos
Energia Solar , Compostos de Cálcio , Cicloexanos , Mesilatos , Óxidos , Titânio
13.
Bioorg Med Chem ; 73: 117002, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36170759

RESUMO

A synthetic scheme was developed to derive a modified ribothymidine bearing a 3-(N-methylsulfamoyl)propyl group on 2'-oxygen (TMSP). For synthesis initiation, a nucleophilic attack of 1,2-ethanediol on 5'-protected 2,2'-anhydro-ribothymidine was performed to selectively modify the 2'-position. After protection of the 3'-hydroxy group, the hydroxyethyl group was oxidized to the aldehyde, which was coupled with isobutyl (diethoxyphosphinyl)methanesulfonate through the Horner-Wadsworth-Emmons reaction to yield the sulfonate intermediate. The intermediate was further converted to the desired TMSP. Using the phosphoramidite units derived from nucleosides, we synthesized oligonucleotides incorporating TMSP. Oligonucleotides modified with TMSP were found to have duplex stability, resistance toward 3'-exonuclease digestion, and antisense activity comparable to that of the oligonucleotide modified with a previously reported 2'-O-methylcarbamoylethyl group. Based on these results and the generality of the synthetic scheme, 2'-O-sulfamoylalkyl modification is expected to be used for the modulation of the properties of oligonucleotides by changing the substituents on the nitrogen, enabling the oligonucleotides to possess suitable properties for antisense oligonucleotides.


Assuntos
Nucleosídeos , Oligonucleotídeos Antissenso , Aldeídos , Etilenoglicol , Mesilatos , Nitrogênio , Oligonucleotídeos , Oxigênio , Uridina/análogos & derivados
14.
Bioorg Med Chem ; 73: 117029, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36174449

RESUMO

A convenient route for the preparation of l-gulose and its C-6 derivatives starting from commercially available 2,3:5,6-diisopropylidene-d-mannofuranose via C-5 epimerization as the key step was developed. 1-O-Benzylation followed by regioselective hydrolysis of the 5,6-isopropylidene group furnished benzyl 2,3-isopropylidene-α-d-mannofuranoside, which was subjected upon regioselective one-pot 6-O-benzoylation and 5-O-mesylation, providing the corresponding 5-OMs-6-OBz derivative in excellent selectivity. Treatment of this mesylate compound with potassium t-butoxide to remove the benzoyl group followed by intramolecular SN2 inversion led to benzyl 5,6-anhydro-2,3-isopropylidene-ß-l-gulofuranoside, which could undergo not only nucleophilic substitutions to open the epoxide ring to give various C-6 derivatives, but also acidic hydrolysis to yield 1,6-anhydro-ß-l-gulopyranose for further transformation into l-gulopyranosyl pentaacetate.


Assuntos
Compostos de Epóxi , Mesilatos , Alcenos , Hexoses , Potássio
15.
Neurol Sci ; 43(12): 6771-6782, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36006553

RESUMO

BACKGROUND: Previous meta-analysis had concluded that desferrioxamine mesylate (DFO) could effectively treat intracerebral hematoma (ICH) in animal models. We hope to confirm that DFO could treat ICH patients effectively through the systemic review and meta-analysis of clinical researches. METHOD: Data extraction included hematoma volume (HV), reduction of National Institute of Health Stroke Scale (NIHSS) scores, and relative perihematomal edema (RPHE). The standard mean difference (SMD) and 95% confidence interval (95%CI) were calculated by fixed effects model. I-square (I2) statistic was used to test the heterogeneity. All p values were two-side with a significant level at 0.05. RESULTS: Five randomized controlled trials were included in the meta-analysis, which included 239 patients. At 7 days after onset, there was significant difference of RPHE development (- 1.87 (- 2.22, - 1.51) (I2 = 0, p = 0.639)) and significant difference of HV absorption (- 0.71 (- 1.06, 0.36) (I2 = 17.5%, p = 0.271)) between DFO and control groups. There was significant difference of reduction of NHISS scores (0.25 (0.05, 0.46) (I2 = 0, p = 0.992)) between DFO and control groups at 30 days after onset. CONCLUSION: DFO reduced HV and perihematomal edema in ICH patients at 7 days after onset and improve neurological function at 30 days after onset efficiently and safely. DFO might be a new route of improving treatment of ICH.


Assuntos
Edema Encefálico , Desferroxamina , Animais , Edema Encefálico/tratamento farmacológico , Edema Encefálico/etiologia , Hemorragia Cerebral/tratamento farmacológico , Desferroxamina/uso terapêutico , Hematoma/diagnóstico por imagem , Hematoma/tratamento farmacológico , Mesilatos/uso terapêutico
16.
Sci Total Environ ; 851(Pt 1): 158007, 2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-35970459

RESUMO

Accurate estimation on reaction nitrogen (Nr) deposition is highly demanded for assessing the impacts on the environment and human beings. This study investigated the wet deposition of inorganic nitrogen (IN) in mainland China by measurements from over 500 sites from five observational networks/databases and ensemble results of eleven chemical transport models (CTMs). Each data source has its focus and limitations and together formed a comprehensive view over China. But the inconsistency among different sources may hinder the appropriate usage of data. Model evaluation results demonstrated the models' deficiency in simulating the wet NO3- deposition over Southeast China (40 % underestimation) and showed an overall underestimation of wet NH4+ deposition over the hotspot regions (5-60 % underestimation). A synthesis of this study and twelve reference studies was conducted to quantify the national amount of wet IN deposition. The estimations by CTMs ranged 2.4-3.9 Tg(N) yr-1 for wet NOy deposition and 4-6.7 Tg(N) yr-1 for wet NHx deposition, after adjusting the results with 10-19 % underestimations in wet NOy deposition and 1-40 % underestimations in wet NHx deposition. The estimations by ground observations ranged 7.1-9 Tg(N) yr-1 for wet NOy deposition and 8-13.1 Tg(N) yr-1 for wet NHx deposition, which were 20-275 % higher than the estimation by CTMs, but the results were strongly influenced by the abundances and representative of measurements. Studies using statistical techniques to interpolate site observations predicted 3-5.5 Tg(N) yr-1 for wet NOy deposition and 3.9-7.2 Tg(N) yr-1 for wet NHx deposition. This approach benefited from high accuracy and good robustness of the statistical models, but the uncertainty in the interpolation methods could be a potential drawback.


Assuntos
Poluentes Atmosféricos , Nitrogênio , Poluentes Atmosféricos/análise , China , Cicloexanos , Monitoramento Ambiental/métodos , Humanos , Mesilatos , Nitrogênio/análise
18.
Zhongguo Zhen Jiu ; 42(8): 844-8, 2022 Aug 12.
Artigo em Chinês | MEDLINE | ID: mdl-35938324

RESUMO

OBJECTIVE: To compare the effect of micro-needle knife therapy and betahistine mesilate tablets in the treatment of cervical vertigo (CV) and the influence on the mean blood flow velocity (Vm) of vertebral artery. METHODS: A total of 200 patients with CV were randomly divided into a micro-needle knife group (100 cases, 5 cases dropped off) and a medication group (100 cases, 3 cases dropped off). In the micro-needle knife group, micro-needle knife was performed on the suboccipital triangle of the atlantoaxial segment of the posterior neck, once every other day, for a total of 7-time treatment. The medication group received oral betahistine mesilate tablets, 6 mg each time, three times a day, for 14 consecutive days. The dizziness handicap inventory (DHI) scores of the two groups were observed before treatment, after treatment and during follow-up 3 months after treatment; the Vm of vertebral artery was compared between the two groups before and after treatment, and the clinical effect was evaluated during follow-up. RESULTS: After treatment and during follow-up, the DHI scores of the two groups were lower than those before treatment (P<0.001), and those in the micro-needle knife group were lower than the medication group (P<0.001). After treatment, the Vm of bilateral vertebral arteries in both groups was higher than that before treatment (P<0.05), and that in the micro-needle knife group was higher than the medication group (P<0.05). The total effective rate of the micro-needle knife group was 96.8% (92/95), which was higher than 67.0% (65/97) of the medication group (P<0.001). CONCLUSION: Micro-needle knife therapy can improve vertigo symptoms and balance dysfunction, increase the mean blood flow velocity of vertebral artery in CV patients, and its clinical efficacy is better than oral betahistine mesilate tablets.


Assuntos
beta-Histina , Artéria Vertebral , Hemodinâmica , Humanos , Mesilatos , Resultado do Tratamento , Vertigem/etiologia , Vertigem/terapia
19.
PLoS One ; 17(7): e0270762, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35802631

RESUMO

Acid-sensing ion channels (ASICs) are neuronal, proton-gated, Na+-selective ion channels. They are involved in various physiological and pathological processes such as neurodegeneration after stroke, pain sensation, fear behavior and learning. To obtain information on the activation mechanism of ASIC1a, we attempted in this study to impose distance constraints between paired residues in different channel domains by using cross-linkers reacting with engineered Cys residues, and we measured how this affected channel function. First, the optical tweezer 4'-Bis(maleimido)azobenzene (BMA) was used, whose conformation changes depending on the wavelength of applied light. After exposure of channel mutants to BMA, an activation of the channel by light was only observed with a mutant containing a Cys mutation in the extracellular pore entry, I428C. Western blot analysis indicated that BMA did not cross-link Cys428 residues. Extracellular application of methanethiosulfonate (MTS) cross-linkers of different lengths changed the properties of several Cys mutants, in many cases likely without cross-linking two Cys residues. Our observations suggest that intersubunit cross-linking occurred in the wrist mutant A425C and intrasubunit cross-linking in the acidic pocket mutant D237C/I312C. In these mutants, exposure to cross-linkers favored a non-conducting channel conformation and induced an acidic shift of the pH dependence and a decrease of the maximal current amplitude. Overall, the cross-linking approaches appeared to be inefficient, possibly due to the geometrical requirements for successful reactions of the two ends of the cross-linking compound.


Assuntos
Canais Iônicos Sensíveis a Ácido , Pinças Ópticas , Canais Iônicos Sensíveis a Ácido/metabolismo , Concentração de Íons de Hidrogênio , Mesilatos , Estrutura Terciária de Proteína
20.
Lab Anim ; 56(6): 540-549, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35850552

RESUMO

The objective of this study was to describe prolonged surgical anaesthesia and recovery in fire salamanders (Salamandra salamandra) using tricaine methanesulfonate (MS-222). A total of 14 salamanders were anaesthetised for electromyography wire implantation. Sodium bicarbonate buffered solutions (0.5-4 g l-1) of MS-222 were prepared (adjusted to pH 7.0). Anaesthesia was induced by partial immersion in pre-oxygenated 3 g l-1 solution for 20 min. Buprenorphine (0.5 mg kg-1) was administered subcutaneously. During microsurgery, heart rate (HR), solution pH and temperature were recorded. Reflectance pulse oximeter (SpO2) (Masimo Rad-57) was recorded in two salamanders. Anaesthetic plane and MS-222 pH stability (pH 7.6) were maintained by renewing administration of oxygenated MS-222 solution (0.5-3 g l-1) onto swabs that partially covered the body. Recovery started at the end of surgery (MS-222 0 g l-1). Postoperatively, salamanders were given oral meloxicam (0.2 mg kg-1). Mean time for loss of righting reflex during induction was 13.7 ± 2.2 min. Duration of anaesthesia and time to recovery were 111 ± 24.2 and 31 ± 10.3 min, respectively. Due to complications, two salamanders did not recover. Baseline HR was 67.4 ± 34.5 beats/min, and it decreased significantly until recovery (p ≤ 0.0001). In two salamanders, baseline SpO2 was 85.5% ± 14.5, SpO2 during surgery was 61% ± 6.4, improving to 80.5% ± 2.1 on recovery.In conclusion, prolonged recovery anaesthesia is achievable with MS-222 dilutions in salamander. Reflectance SpO2 could prove valuable during immersion anaesthesia.


Assuntos
Anestesia , Salamandra , Animais , Aminobenzoatos , Anestesia/métodos , Mesilatos
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