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1.
Sci Rep ; 14(1): 21434, 2024 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-39271709

RESUMO

Systemic arterial hypertension is accompanied by autonomic impairments that, if not contained, promotes cardiac functional and morphological damages. Pyridostigmine bromide (PYR) treatment results in positive effects on autonomic control and beneficial cardiac remodeling. These findings were also observed after aerobic physical training (APT). However, little is known about PYR effects on left ventricular contractility, mainly when it is combined with APT. We aimed to investigate the effects of chronic acetylcholinesterase inhibition on cardiac autonomic tone balance, coronary bed reactivity, and left ventricular contractility in spontaneously hypertensive rats (SHR) submitted to APT. Male SHR (18 weeks) were divided into two groups (N = 16): untrained and submitted to APT for 14 weeks (18th to 32nd week). Half of each group was treated with PYR (15 mg/kg/day) for two weeks (31st to 32nd week). The experimental protocol consisted of recording hemodynamic parameters, double autonomic blockade with atropine and propranolol, and assessment of coronary bed reactivity and ventricular contractility in isolated hearts using the Langendorff technique. PYR and APT reduced blood pressure, heart rate, and sympathetic influence on the heart. The Langendorff technique showed that APT increased coronary perfusion pressure and left ventricle contractility in response to coronary flow and ß-agonist administration. However, treatment with PYR annulled the effects of APT. In conclusion, although chronic treatment with PYR reduces cardiac sympathetic tonic influence, it does not favor coronary bed reactivity and cardiac contractility gains. PYR treatment in the trained SHR group nullified the coronary vascular reactivity and cardiac contractility gains.


Assuntos
Inibidores da Colinesterase , Hipertensão , Contração Miocárdica , Condicionamento Físico Animal , Brometo de Piridostigmina , Ratos Endogâmicos SHR , Animais , Inibidores da Colinesterase/farmacologia , Masculino , Ratos , Contração Miocárdica/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Brometo de Piridostigmina/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/fisiopatologia , Função Ventricular Esquerda/efeitos dos fármacos , Acetilcolinesterase/metabolismo
2.
Environ Sci Technol ; 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39297711

RESUMO

Aniline-related structures are common in anthropogenic chemicals, such as pharmaceuticals and pesticides. Compared with the widely studied phenolic compounds, anilines have received far less assessment of their disinfection byproduct (DBP) formation potential, even though anilines and phenols likely exhibit similar reactivities on their respective aromatic rings. In this study, a suite of 19 aniline compounds with varying N- and ring-substitutions were evaluated for their formation potentials of haloacetonitriles and trihalomethanes under free chlorination and free bromination conditions. Eight of the aniline compounds formed dichloroacetonitrile at yields above 0.50%; the highest yields were observed for 4-nitroaniline, 3-chloroaniline, and 4-(methylsulfonyl)aniline (1.6-2.3%). Free bromination generally resulted in greater haloacetonitrile yields with the highest yield observed for 2-ethylaniline (6.5%). The trihalomethane yields of anilines correlated with their haloacetonitrile yields. Product analysis of aniline chlorination by liquid chromatography-high-resolution mass spectrometry revealed several large-molecule DBPs, including chloroanilines, (chloro)hydroxyanilines, (chloro)benzoquinone imines, and ring-cleavage products. The product time profiles suggested that the reaction pathways include initial ring chlorination and hydroxylation, followed by the formation of benzoquinone imines that eventually led to ring cleavage. This work revealed the potential of aniline-related moieties in micropollutants as potent precursors to haloacetonitriles and other emerging large-molecule DBPs with the expected toxicity.

3.
Front Neurosci ; 18: 1465701, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39308947

RESUMO

Gulf War Illness (GWI) affects nearly 30% of veterans from the 1990-1991 Gulf War (GW) and is a multi-symptom illness with many neurological effects attributed to in-theater wartime chemical overexposures. Brain-focused studies have revealed persistent structural and functional alterations in veterans with GWI, including reduced volumes, connectivity, and signaling that correlate with poor cognitive and motor performance. GWI symptomology components have been recapitulated in rodent models as behavioral, neurochemical, and neuroinflammatory aberrations. However, preclinical structural imaging studies remain limited. This study aimed to characterize the progression of brain structural alterations over the course of 12 months in two established preclinical models of GWI. In the PB/PM model, male C57BL/6 J mice (8-9 weeks) received daily exposure to the nerve agent prophylactic pyridostigmine bromide (PB) and the pyrethroid insecticide permethrin (PM) for 10 days. In the PB/DEET/CORT/DFP model, mice received daily exposure to PB and the insect repellent DEET (days 1-14) and corticosterone (CORT; days 7-14). On day 15, mice received a single injection of the sarin surrogate diisopropylfluorophosphate (DFP). Using a Varian 7 T Bore MRI System, structural (sagittal T2-weighted) scans were performed at 6-, 9-, and 12-months post GWI exposures. Regions of interest, including total brain, ventricles, cortex, hippocampus, cerebellum, and brainstem were delineated in the open source Aedes Toolbox in MATLAB, followed by brain volumetric and cortical thickness analyses in ImageJ. Limited behavioral testing 1 month after the last MRI was also performed. The results of this study compare similarities and distinctions between these exposure paradigms and aid in the understanding of GWI pathogenesis. Major similarities among the models include relative ventricular enlargement and reductions in hippocampal volumes with age. Key differences in the PB/DEET/CORT/DFP model included reduced brainstem volumes and an early and persistent loss of total brain volume, while the PB/PM model produced reductions in cortical thickness with age. Behaviorally, at 13 months, motor function was largely preserved in both models. However, the GWI mice in the PB/DEET/CORT/DFP model exhibited an elevation in anxiety-like behavior.

4.
Small ; : e2405758, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39286991

RESUMO

Control over the lateral dimensions of colloidal nanostructures is a complex task which requires a deep understanding of the formation mechanism and reactivity in the corresponding systems. As a result, it provides a well-founded insight to the physical and chemical properties of these materials. In this work, the preparation of quasi-2D methylammonium lead bromide nanostripes and discuss the influence of some specific parameters on the morphology and stability of this material is demonstrated. The variation in the amount of the main ligand dodecylamine gives a large range of structures beginning with 3D brick-like particles at low concentrations, nanostripes at elevated and ultimately nanosheets at large concentrations. The amount of the co-ligand trioctylphosphine can alter the width of the nanostripe shape to a certain degree. The thickness can be adjusted by the amount of the second precursor methylammonium bromide. Additionally, insights are given for the suggested formation mechanism of these anisotropic structures as well as for stability against moisture at ambient conditions in comparison with differently synthesized nanosheet samples.

5.
Bioelectrochemistry ; 161: 108798, 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39243734

RESUMO

Coronavirus disease (COVID-19) is caused by infection with the SARS-CoV-2 virus, having already caused more than seven million deaths worldwide. Conventional techniques for SARS-CoV-2 detection have limitations, as high cost, low specificity, and longer analysis time, among others. Biosensors emerge as a necessary alternative to overcome the difficulties of current diagnostics. This paper reports a sensor platform where silver-doped zinc oxide nanomaterial (Ag:ZnONp) was used onto carbon screen-printed electrode and ethidium bromide as indicator for development of a specific electrochemical genosensor for COVID-19. This genosensor demonstrated good linearity between the concentrations of 5.62 × 104-5.62 copies/mL and a detection limit of 5 copies/mL with gRNA in patient's samples, with a response time within 30 min. Molecular modeling and morphological analysis are in agreement with obtained electrochemical results. Additional techniques such as AFM, SEM, and EIS were conducted to characterize the morphological and electrochemical properties of the biosensor's surface. The biosensor was also capable of detecting the target presence in spiked samples and demonstrated a stability of 60 days, higher than other similar biosensors for SARS-CoV-2.

6.
Anat Rec (Hoboken) ; 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39223934

RESUMO

Embryonic muscle activity is involved in various aspects of bone morphogenesis and growth. Normal mechanical stimuli of muscle contraction are important in most cases, and when the muscles are immobilized, the developing bones are abnormally shaped. In chick embryos, a characteristic curved deformity is reproducibly induced in the developing tibiotarsus using the bone-weakening agent, beta-aminopropionitrile (bAPN). In this study, we applied decamethonium bromide (DMB), a well-established neuromuscular blocking agent, to embryos treated with bAPN, to test the hypothesis that the deformity is triggered and formed depending on the balance between the decrease in stiffness of the bAPN-affected tibiotarsus and the normal physiological increase in embryonic skeletal muscle activity. The occurrence of curved morphology induced by bAPN administered at 4 or 8 days of incubation (embryonic day [ED]) was temporally consistent with the posterior displacement of the leg muscles, which occurred just before ED8. The displaced muscles were assumed to exert a contraction force comparable to that of untreated normal muscles. When treated with DMB at ED8, the muscles atrophied and exhibited degenerative changes, and the degree of curved morphology was alleviated and reduced to 50% or more in the morphometric evaluation at ED10. These findings indicated that the coordinated development of skeletal element stiffness and muscle activity must be temporally regulated, particularly during the early stages of skeletogenesis.

7.
IUCrdata ; 9(Pt 8): x240653, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39247074

RESUMO

The structure of pinaverium bromide (systematic name: 4-[(2-bromo-4,5-di-meth-oxy-phen-yl)meth-yl]-4-{2-[2-(6,6-dimethyl-2-bi-cyclo-[3.1.1]hepta-nyl)eth-oxy]eth-yl}morpholin-4-ium bromide; C26H41Br2NO4), was determined at 110 K. It has monoclinic (P21) symmetry. It is of inter-est with respect to its anti-inflammatory properties. The asymmetric unit contains two independent mol-ecules, one of which exhibits disorder of the bi-cyclo terminal group (occupancy factors: 0.78 and 0.22).

8.
Artigo em Inglês | MEDLINE | ID: mdl-39200575

RESUMO

BACKGROUND: Deployment-related neurotoxicant exposures are implicated in the etiology of Gulf War illness (GWI), the multisymptom condition associated with military service in the 1990-1991 Gulf War (GW). A Q/R polymorphism at position 192 of the paraoxonase (PON)-1 enzyme produce PON1192 variants with different capacities for neutralizing specific chemicals, including certain acetylcholinesterase inhibitors. METHODS: We evaluated PON1192 status and GW exposures in 295 GWI cases and 103 GW veteran controls. Multivariable logistic regression determined independent associations of GWI with GW exposures overall and in PON1192 subgroups. Exact logistic regression explored effects of exposure combinations in PON1192 subgroups. RESULTS: Hearing chemical alarms (proxy for possible nerve agent exposure) was associated with GWI only among RR status veterans (OR = 8.60, p = 0.014). Deployment-related skin pesticide use was associated with GWI only among QQ (OR = 3.30, p = 0.010) and QR (OR = 4.22, p < 0.001) status veterans. Exploratory assessments indicated that chemical alarms were associated with GWI in the subgroup of RR status veterans who took pyridostigmine bromide (PB) (exact OR = 19.02, p = 0.009) but not RR veterans who did not take PB (exact OR = 0.97, p = 1.00). Similarly, skin pesticide use was associated with GWI among QQ status veterans who took PB (exact OR = 6.34, p = 0.001) but not QQ veterans who did not take PB (exact OR = 0.59, p = 0.782). CONCLUSION: Study results suggest a complex pattern of PON1192 exposures and exposure-exposure interactions in the development of GWI.


Assuntos
Arildialquilfosfatase , Guerra do Golfo , Síndrome do Golfo Pérsico , Veteranos , Humanos , Arildialquilfosfatase/genética , Síndrome do Golfo Pérsico/genética , Síndrome do Golfo Pérsico/epidemiologia , Masculino , Estudos de Casos e Controles , Veteranos/estatística & dados numéricos , Pessoa de Meia-Idade , Adulto , Feminino , Polimorfismo Genético , Exposição Ocupacional , Modelos Logísticos , Praguicidas/toxicidade , Inibidores da Colinesterase , Estados Unidos/epidemiologia
9.
Artigo em Inglês | MEDLINE | ID: mdl-39169694

RESUMO

DISCLAIMER: In an effort to expedite the publication of articles, AJHP is posting manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time. PURPOSE: Elevated serum bromide levels can cause dermatological, gastrointestinal, and neurological abnormalities. As bromide and chloride are both halogens, bromide may interfere with chloride assays, causing a falsely high serum chloride concentration and a low or negative anion gap. There is a paucity of data describing bromide toxicity from high doses of pyridostigmine bromide (PB). This case report describes a patient with an elevated bromide level with neurological symptoms from a therapeutic dose of PB. SUMMARY: A 37-year-old male with myasthenia gravis secondary to type B2 thymoma status following thymectomy presented in myasthenic crisis. He required mechanical ventilation and was managed with steroids, intravenous immune globulin, plasmapheresis, and PB. On day 9, the patient experienced acute agitation. He had an anion gap of 2 mEq/L and a chloride concentration of 109 mEq/L. The plasma creatinine concentration was 0.63 to 1.15 mg/dL and urine output was 0.76 to 1.79 mL/kg/h throughout his admission. All other laboratory values were normal. The daily dose of PB was 660 mg on day 9, but the patient received 76 mg of intravenous PB over the first few days of his admission with the largest dose in 24 hours equal to 48 mg. On day 10, the patient's bromide level was 37 µg/mL. His agitation was initially managed with quetiapine, followed by PB dose reduction. To our knowledge, there are 2 cases in the literature of bromide toxicity secondary to PB. These patients experienced neurological symptoms with bromide levels of 88 to 90 µg/mL. Bromide concentrations of more than 12 µg/mL are associated with a higher risk of neuronal dysfunction demonstrated as disturbances on an electroencephalogram, and levels greater than 50 µg/mL are considered toxic. While our patient's bromide level was not as high as those previously reported, no other causes for his agitation were identified. CONCLUSION: Elevated bromide levels from therapeutic PB can occur, and monitoring of these levels should be considered.

10.
Water Res ; 263: 122190, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39106622

RESUMO

We investigated the formation of nitrosamines from urine during electrochemical chlorination (EC) using dimensionally stable anodes. Short-term electrolysis (< 1 h) of urine at 25 mA cm-2 generated seven nitrosamines (0.1-7.4 µg L-1), where N-nitrosodimethylamine, N-nitrosomethylethylamine, and N-nitrosodiethylamine were predominant with concentrations ranging from 1.2 to 7.4 µg L-1. Mechanistic studies showed that the formation kinetics of nitrosamines was influenced by urine aging and composition, with fresh urine generating the highest levels (0.9-5.8 µg L-1) compared with aged, centrifuged, or filtered urine (0.2-4.1 µg L-1). Concurrently, studies on urine pretreatment through filtration and centrifugation underscored the significance of nitrogenous metabolites (such as protein-like products and urinary amino acids) and particle-associated humic fractions in nitrosamine formation during EC of urine. This finding was confirmed through chromatographic and spectroscopic studies utilizing LCOCD, Raman spectra, and 3DEEM fluorescence spectra. Parametric studies demonstrated that the ultimate [nitrosamines] increased at a pH range of 4.5-6.2, and with increasing [bromide], [ammonium], and current density. Conversely, sulfate and carbonate ions inhibited nitrosamine formation. Moreover, the implications of EC in urine-containing source waters were evaluated. The results indicate that regardless of the urine source (individual volunteers, septic tank, swimming pool, untreated municipal wastewater), high levels of nitrosamines (0.1-17.6 µg L-1) were generated, surpassing the potable reuse guideline of 10 ng L-1. Overall, this study provides insights to elucidate the mechanisms underlying nitrosamine formation and optimize the operating conditions. Such insights facilitate suppressing the generation of nitrosamine byproducts during electrochemical treatment of urine-containing wastewater.


Assuntos
Halogenação , Nitrosaminas , Nitrosaminas/urina , Purificação da Água , Urina/química , Poluentes Químicos da Água/química , Humanos
11.
Artigo em Russo | MEDLINE | ID: mdl-39113443

RESUMO

Mutations in the human PCDH19 gene lead to epileptic encephalopathy of early childhood. It is characterized by the early onset of serial seizures, cognitive impairment and behavioral disorders (including autistic personality traits). In most cases, difficulties arise in selecting therapy due to pharmacoresistance. The pathogenesis of the disease is complex. The data available to us at the moment from numerous studies present the pathogenesis of «PCDH19 syndrome¼ as multi-level, affecting both the epigenetic support of cell life, and development of stem cells and progenitor cells in the process of neuroontogenesis, and the influence on the neurotransmitter mechanisms of the brain, and disruption of the formation of neural networks with an inevitable increase in the excitability of the cerebral cortex as a whole, and local changes in the highly labile regulatory structures of the hippocampal region. And it is not surprising that all these changes entail not only (and perhaps not so much) epileptization, but a profound disruption of the regulation of brain activity, accompanied by autism spectrum disorders, more profound disorders in the form of schizophrenia or cyclothymia, and the formation of delayed psychomotor development. A «side branch¼ of these pathogenetic processes can also be considered the participation of PCDH19 dysfunctions in certain variants of oncogenesis. The need for polypharmacy (in most cases) confirms the diversity of mechanisms involved in the pathogenesis of the disease and makes the prospects for the development of effective and rational treatment regimens very vague. Cautious optimism is caused only by attempts at relatively specific treatment with ganaxolone.


Assuntos
Epilepsia , Polimedicação , Humanos , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/tratamento farmacológico , Encéfalo , Caderinas/genética , Epilepsia/tratamento farmacológico , Epilepsia/genética , Mutação , Protocaderinas
12.
ACS Nano ; 18(33): 22208-22219, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39115283

RESUMO

We investigate the early stages of cesium lead bromide perovskite formation through absorption spectroscopy of stopped-flow reactions, high-throughput mapping, and direct synthesis and titration of potential precursor species. Calorimetric and spectroscopic measurements of lead bromide complex titrations combined with theoretical calculations suggest that bromide complexes with higher coordination numbers than previously considered for nonpolar systems can better explain observed behaviors. Synthesis mapping of binary lead halides reveals multiple lead bromide species with absorption peaks higher than 300 nm, including a previously observed species with a peak at 313 nm and two species with peaks at 345 and 370 nm that also appear as reaction intermediates during the formation of lead bromide perovskites. Based on theoretical calculations of excitonic energies that match within 50 meV, we give a preliminary assignment of these species as two-dimensional magic-sized clusters with side lengths of 2, 3, and 4 unit cells. Kinetic measurements of the conversion of benzoyl bromide precursor are connected to stopped-flow measurements of product formation and demonstrate that the formation of complexes and magic-sized clusters (i.e., nucleation) is controlled by precursor decomposition, whereas the growth rate of 2D and 3D perovskites is significantly slower.

13.
Sci Rep ; 14(1): 19744, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39187626

RESUMO

A leading cause of global warming is the increase of carbon dioxide (CO2) emissions due to anthropogenic activities which prompts an urgent need for substantial reduction. Recently, CO2 absorption in deep eutectic solvents (DESs) has attracted scientific attention, because of their adaptability compared to traditional ionic liquids and aqueous amine solutions. This study employs the heating method to synthesize DESs using tetrapropylammonium bromide (TPAB) and formic acid (Fa) with molar ratios of TPAB-Fa (1:1) and TPAB-Fa (1:2). Absorption experiments by static method quantified CO2 solubility in the DESs under varied pressures and temperatures. TPAB-Fa (1:2) at 25.0 °C was the most efficient with the CO2 solubility of 0.218. Thermodynamic modeling was performed by employing the nonrandom two liquids activity coefficient model and the Peng-Robinson equation of state for the liquid and gas phases, respectively. The Henry's law constant was determined from experimental data. CO2 physical absorption was confirmed via nuclear magnetic resonance (NMR) and Fourier-transform infrared (FT-IR) analyses. TPAB-Fa (1:2), as the superior DES, exhibited regeneration efficiency of 99% after five absorption/desorption cycles.

14.
Acta Pharmacol Sin ; 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39160244

RESUMO

Pulmonary fibrosis (PF) is a chronic, progressive and irreversible interstitial lung disease characterized by unremitting pulmonary myofibroblasts activation, extracellular matrix (ECM) deposition and inflammatory recruitment. PF has no curable medication yet. In this study we investigated the molecular pathogenesis and potential therapeutic targets of PF and discovered drug lead compounds for PF therapy. A murine PF model was established in mice by intratracheal instillation of bleomycin (BLM, 5 mg/kg). We showed that the protein level of pulmonary protein phosphatase magnesium-dependent 1A (PPM1A, also known as PP2Cα) was significantly downregulated in PF patients and BLM-induced PF mice. We demonstrated that TRIM47 promoted ubiquitination and decreased PPM1A protein in PF progression. By screening the lab in-house compound library, we discovered otilonium bromide (OB, clinically used for treating irritable bowel syndrome) as a PPM1A enzymatic activator with an EC50 value of 4.23 µM. Treatment with OB (2.5, 5 mg·kg-1·d-1, i.p., for 20 days) significantly ameliorated PF-like pathology in mice. We constructed PF mice with PPM1A-specific knockdown in the lung tissues, and determined that by targeting PPM1A, OB treatment suppressed ECM deposition through TGF-ß/SMAD3 pathway in fibroblasts, repressed inflammatory responses through NF-κB/NLRP3 pathway in alveolar epithelial cells, and blunted the crosstalk between inflammation in alveolar epithelial cells and ECM deposition in fibroblasts. Together, our results demonstrate that pulmonary PPM1A activation is a promising therapeutic strategy for PF and highlighted the potential of OB in the treatment of the disease.

15.
Vaccines (Basel) ; 12(8)2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39203969

RESUMO

BACKGROUND: The problem of identifying vaccine-specific T-cell responses is still a matter of debate. Currently, there are no universal, clearly defined, agreed upon criteria for assessing the effectiveness of vaccinations and their immunogenicity for the cellular component of immunity, even for healthy people. But for patients with inborn errors of immunity (IEI), especially those with antibody deficiencies, evaluating cellular immunity holds significant importance. AIM: To examine the effect of one and two doses of inactivated adjuvanted subunit influenza vaccines on the expression of endosomal Toll-like receptors (TLRs) on the immune cells and the primary lymphocyte subpopulations in patients with common variable immunodeficiency (CVID). MATERIALS AND METHODS: During 2018-2019, six CVID patients received one dose of a quadrivalent adjuvanted influenza vaccine; in 2019-2020, nine patients were vaccinated with two doses of a trivalent inactivated influenza vaccine. The proportion of key lymphocyte subpopulations and expression levels of TLRs were analyzed using flow cytometry with monoclonal antibodies. RESULTS: No statistically significant alterations in the absolute values of the main lymphocyte subpopulations were observed in CVID patients before or after vaccination with the different immunization protocols. However, after vaccination, a higher expression of TLR3 and TLR9 in granulocytes, monocytes, and lymphocytes was found in those patients who received two vaccine doses rather than one single dose. CONCLUSION: This study marks the first instance of using a simultaneous two-dose vaccination, which is associated with an elevated level of TLR expression in the immune cells. Administration of the adjuvanted vaccines in CVID patients appears promising. Further research into their impact on innate immunity and the development of more effective vaccination regimens is warranted.

16.
Electrophoresis ; 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39091179

RESUMO

Various dyes are used to visualize DNA bands in agarose gel electrophoresis (AGE) by the methods of pre- or post-staining. The DNA dye user's guides generally state that the binding of the dye to DNA will affect DNA mobility in electrophoresis, thus recommending post-staining for accurate measurement of DNA size. However, many AGE performers prefer pre-staining procedures for reasons such as convenience, real-time observation of DNA bands, and/or the use of a minimal amount of dye. The detrimental effect of the dye on DNA mobility and the associated risk for inaccurate measurement of DNA size are often overlooked by AGE performers. Here we quantitatively determine the impact on DNA migration imposed by frequently used dyes, including GelRed, ethidium bromide (EB), and Gold View. It was observed that pre-staining with GelRed and EB significantly slowed down DNA migration to cause as much as 39.1% overestimation on the size of sample DNA, whereas Gold View had little effect. The slowdown of DNA migration increased with dye concentration until it plateaued when the dye concentration reached a saturated level. Thus, to take advantage of pre-staining, saturated levels of DNA dyes should always be applied for both DNA samples and DNA markers to ensure a fair comparison of DNA sizes. In addition, GelRed and EB display much higher sensitivity than Gold View in the detection of DNA bands in post-staining. The saturated concentrations, cost considerations, and other useful features of these frequently used dyes are summarized for the information of AGE performers.

17.
Small ; : e2401847, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39092663

RESUMO

Bismuth halide hybrid perovskites have emerged as promising alternatives to their lead halide homologs because of high chemical stability, low toxicity, and structural diversity. However, their advancements in optoelectronic field are plagued with poor charge transport, due to considerable microstrain triggered by bulky spacer. Herein, the di-tertiary ammonium spacer (N,N,N',N'-tetramethyl-1,4-butanediammonium, TMBD) is explored to direct stable 1D bismuth bromide lattice structure with relaxed microstrain. Compared to the primary pentamethylenediamine (PD)2+, the (TMBD)2+ adopting alternating alignment enables a unique H-bonds mode to distort the configuration of inorganic layers to form corner-sharing [BiBr5] near-regular chains with narrower bandgap, lower exciton binding energy, and reduced carrier-lattice interactions, thereby facilitating charge-carrier transport. Moreover, the (TMBD)2+ spacers largely suppress ion migration in perovskite lattice, as substantiated by the experimental and theoretical investigations. Consequently, (TMBD)BiBr5 single crystal photodetector delivers a 185-fold increase in current on/off ratio with respect to (PD)BiBr5 under white light irradiation, considerable responsivity (≈82.97 mA W-1), detectivity (≈8.06 ×1011 Jones) under weak light (0.02 mW cm-2) irradiation, in the top rank of the reported hybrid bismuth halide perovskites. This finding offers novel design criterion for high-performance lead-free perovskites.

18.
Pak J Med Sci ; 40(7): 1338-1344, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39092049

RESUMO

Objective: To explore the clinical effect of various doses of Budesonide combined with Tiotropium bromide in the treatment of elderly patients with chronic obstructive pulmonary disease (COPD). Methods: Clinical data of elderly patients with COPD, admitted to Affiliated Hospital of Shaoxing University from April 2021 to February 2023, were retrospectively analyzed. Based on the dosage of Budesonide combined with Tiotropium bromide, patients were divided into Low-dose group (Budesonide = 1mg), Medium-dose group (Budesonide = 2mg), and High-dose group (Budesonide = 3mg). All groups were matched for age, gender, course of disease, and BMI. Patients treated with Tiotropium bromide alone were assigned to the Control group. The clinical effect, pulmonary function index level, symptom improvement, inflammatory factor index level and adverse reactions in all groups were analyzed and compared. Results: A total of 88 patients were included in this study with 22 patients in each group. The total efficacy of Medium-dose (90.91%) and High-dose group (90.91%) was significantly higher than that of Low-dose group (63.64%) and the Control group (59.09%) (P<0.05). After the treatment, levels of pulmonary function, symptom improvement and inflammatory factors in the High-dose and the Medium-dose groups were better than those in the Low-dose group and the Control group. Pulmonary function, symptom improvement and levels of inflammatory factors was significantly better in the Low-dose group compared to the Control group (P<0.05). Conclusions: Budesonide combined with tiotropium bromide is better than tiotropium bromide alone in the treatment of elderly patients with COPD. Compared with low (1mg) dosage, medium (2mg) and high (3mg) dosage of budesonide are more effective in improving lung function, alleviating symptoms, reducing inflammatory response,, and are not associated with increased rate of adverse reactions.

19.
Methods Mol Biol ; 2841: 95-100, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39115768

RESUMO

Lignin is a tough biopolymer that gives plants strength and protection. It is also a major obstacle for converting plant biomass into biofuels because it prevents enzymes from accessing the sugar-rich fibers. To optimize biofuel production, we need to measure the lignin content in plant tissues accurately and efficiently. In this protocol, we describe a simple and reliable method to measure the total lignin content in plant tissues. The method uses acetyl bromide, a chemical that dissolves lignin into soluble derivatives and makes it possible to detect them by their absorbance at 280 nm. The method consists of two steps: first, we obtained destarched cell wall material from the plant samples, and second, we treat the cell wall material with acetyl bromide and measure the absorbance of the lignin solution. This method can capture all types of lignin and works well with different plant tissues.


Assuntos
Biomassa , Parede Celular , Lignina , Plantas , Lignina/análise , Lignina/metabolismo , Parede Celular/química , Parede Celular/metabolismo , Plantas/química , Plantas/metabolismo , Acetileno/química , Acetileno/análise , Biocombustíveis/análise , Acetatos
20.
Heliyon ; 10(14): e34614, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39130425

RESUMO

Kumada cross-coupling reaction is useful for producing biphenyls, where nickel and copper have been widely investigated as catalysts but mainly homogeneous ones. In this study, we investigated ultrasound-assisted-Kumada cross-coupling reaction over the heterogeneous catalysts in which Ni2+, Cu2+, or both was immobilized on aminopropylsilane-functionalized-SiO2-TiO2 prepared in the presence of cetyltrimethylammonium bromide (CTAB). The presence of CTAB effectively prevented the particle growth and therefore SiO2-TiO2 fine particles with high surface area (502 m2 g-1) were formed. The Ni2+-immobilized catalyst showed high catalytic activity for the ultrasound-assisted-Kumada cross-coupling reaction of a wide variety of substrates and was reusable three times. Performing the reaction under ultrasound irradiation was very effective in significantly accelerating the reaction rate compared with the conventional mechanical method. In contrast to Ni2+, Cu2+ was deposited on the support as crystalline Cu(OH)2 and the resulting catalysts with Cu2+ and Ni2+-Cu2+ were less active and less stable under the reaction conditions.

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