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1.
Neurol Neurochir Pol ; 58(2): 176-184, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38324117

RESUMEN

INTRODUCTION: Cognitive impairment occurs from the earliest stages of multiple sclerosis (MS) and progresses over time. The introduction of disease modifying therapies (DMTs) has changed the prognosis for MS patients, offering a potential opportunity for improvement in the cognitive arena as well. MATERIAL AND METHODS: 41 patients with relapsing-remitting multiple sclerosis (MS) were recruited to the study. Thirty patients were available for final follow-up and were included in the analysis. Baseline (BL) brain MRI including volumetry and neuropsychological tests were performed. Blood samples were collected at BL and follow-up (FU) and were tested for: vascular endothelial growth factor (VEGF), soluble vascular cell adhesion molecule-1 (sVCAM1), soluble platelet-endothelial CAM-1 (sPECAM1), and soluble intercellular CAM-1 (sICAM-1). Patients were invited for a final neuropsychological follow-up after a median of 6 years. Disease activity (relapses, EDSS increase, new/active brain lesions on MRI) was analysed between BL and FU. RESULTS: The study group deteriorated in the Rey-Osterrieth Complex Figure (ROCF) test (p = 0.001), but improved significantly in three other tests, i.e. semantic fluency test (p = 0.013), California Verbal Learning Test (CVLT, p = 0.016), and Word Comprehension Test (WCT, p < 0.001). EDSS increase correlated negatively with semantic fluency and WCT scores (r = -0.579, p = 0.001 and r = -0.391, p = 0.033, respectively). Improvements in semantic fluency test and WCT correlated positively with baseline deep grey matter, grey matter, and cortical volumes (p < 0.05, r > 0). Higher EDSS on FU correlated significantly negatively with baseline left and right pallidum, right caudate, right putamen, right accumbens, and cortical volume (p < 0.05, r < 0). No significant relationship was found between the number of relapses and EDSS on FU or neuropsychological deteriorations. Improvements in WCT and CVLT correlated positively with baseline sPECAM1 and sVCAM1 results, respectively (r > 0, p < 0.05). Deterioration in ROCF test correlated significantly with higher levels of baseline VEGF and sVCAM1 (p < 0.05). CONCLUSIONS: Brain volume is an important predictor of future EDSS and cognitive functions outcome. MS patients have a potential for improving in neuropsychological tests over time. It remains to be established whether this is related to successful disease modification with immunotherapy. Baseline volumetric measures are stronger predictors of cognitive performance than relapse activity, which yet again highlights the importance of atrophy in MS prognosis.


Asunto(s)
Disfunción Cognitiva , Progresión de la Enfermedad , Imagen por Resonancia Magnética , Esclerosis Múltiple Recurrente-Remitente , Pruebas Neuropsicológicas , Humanos , Esclerosis Múltiple Recurrente-Remitente/diagnóstico por imagen , Esclerosis Múltiple Recurrente-Remitente/complicaciones , Esclerosis Múltiple Recurrente-Remitente/fisiopatología , Esclerosis Múltiple Recurrente-Remitente/sangre , Esclerosis Múltiple Recurrente-Remitente/psicología , Femenino , Masculino , Adulto , Estudios de Seguimiento , Disfunción Cognitiva/etiología , Persona de Mediana Edad , Pronóstico , Factor A de Crecimiento Endotelial Vascular/sangre
2.
J Aging Phys Act ; 32(2): 185-197, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37989135

RESUMEN

Both navigation abilities and gait can be affected by the atrophy in the medial temporal cortex. This study aimed to determine whether navigation abilities could differentiate seniors with and without medial temporal lobe atrophy who complained about their cognitive status. The participants, classified to either the medial temporal atrophy group (n = 23) or the control group (n = 22) underwent neuropsychological assessment and performed a spatial navigation task while their gait parameters were recorded. The study showed no significant differences between the two groups in memory, fluency, and semantic knowledge or typical measures of navigating abilities. However, gait parameters, particularly the propulsion index during certain phases of the navigation task, distinguished between seniors with and without medial temporal lobe lesions. These findings suggest that the gait parameters in the navigation task may be a valuable tool for identifying seniors with cognitive complaints and subtle medial temporal atrophy.


Asunto(s)
Disfunción Cognitiva , Navegación Espacial , Humanos , Anciano , Imagen por Resonancia Magnética , Lóbulo Temporal/patología , Disfunción Cognitiva/diagnóstico , Marcha , Atrofia/patología , Pruebas Neuropsicológicas
3.
Molecules ; 28(1)2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36615599

RESUMEN

In this article, we describe the antimicrobial properties of pristine anodised aluminium oxide matrices-the material many consider biologically inert. During a typical anodisation process, chromium and chlorine compounds are used for electropolishing and the removal of the first-step aluminium oxide. Matrices without the use of those harmful compounds were also fabricated and tested for comparison. The antibacterial tests were conducted on four strains of Escherichia coli: K12, R2, R3 and R4. The properties of the matrices were also compared to the three types of antibiotics: ciprofloxacin, bleomycin and cloxacillin using the Minimal Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) tests. Moreover, DNA was isolated from the analysed bacteria which was additionally digested with formamidopyrimidine-DNA glycosylase (Fpg) protein from the group of repair glycosases. These enzymes are markers of modified oxidised bases in nucleic acids produced during oxidative stress in cells. Preliminary cellular studies, MIC and MBC tests and digestion with Fpg protein after modification of bacterial DNA suggest that these compounds may have greater potential as antibacterial agents than the aforementioned antibiotics. The described composites are highly specific for the analysed model Escherichia coli strains and may be used in the future as new substitutes for commonly used antibiotics in clinical and nosocomial infections in the progressing pandemic era. The results show much stronger antibacterial properties of the functionalised membranes on the action of bacterial membranes in comparison to the antibiotics in the Fpg digestion experiment. This is most likely due to the strong induction of oxidative stress in the cell through the breakdown of the analysed bacterial DNA.


Asunto(s)
Reparación del ADN , Proteínas de Escherichia coli , Proteínas de Escherichia coli/genética , Aluminio/farmacología , ADN Bacteriano , Óxidos , ADN-Formamidopirimidina Glicosilasa/genética , ADN-Formamidopirimidina Glicosilasa/metabolismo , Escherichia coli/metabolismo , Antibacterianos/farmacología , Óxido de Aluminio
4.
Molecules ; 27(20)2022 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-36296455

RESUMEN

The impact of substituent at phenyl ring of diethyl benzylphosphonate derivatives on cytotoxic activity was studied. The organophosphonates were obtained based on developed palladium-catalyzed α, ß-homodiarylation of vinyl esters protocol. The new synthetic pathway toward 1,2-bis(4-((diethoxyphosphoryl)methyl)phenyl)ethyl acetate was proposed which significantly improves the overall yield of the final product (from 1% to 38%). Several newly synthesized organophosphonates were tested as new potential antimicrobial drugs on model Escherichia coli bacterial strains (K12 and R2-R3). All tested compounds show the highest selectivity and activity against K12 and R2 strains. Preliminary cellular studies using MIC and MBC tests and digestion of Fpg after modification of bacterial DNA suggest that selected benzylphosphonate derivatives may have greater potential as antibacterial agents than typically used antibiotics such as ciprofloxacin, bleomycin and cloxacillin. These compounds are highly specific for pathogenic E. coli strains based on the model strains used and may be engaged in the future as new substitutes for commonly used antibiotics, which is especially important due to the increasing resistance of bacteria to various drugs and antibiotics.


Asunto(s)
Antiinfecciosos , Organofosfonatos , Pruebas de Sensibilidad Microbiana , Escherichia coli/metabolismo , Paladio , ADN Bacteriano , Antibacterianos , Bacterias/metabolismo , Organofosfonatos/farmacología , Cloxacilina , Ciprofloxacina , Ésteres , Bleomicina
5.
Int J Mol Sci ; 23(15)2022 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-35955460

RESUMEN

In this article, we describe the antimicrobial properties of a new composite based on anodic aluminium oxide (AAO) membranes containing propyl-copper-phosphonate units arranged at a predetermined density inside the AAO channels. The samples were prepared with four concentrations of copper ions and tested as antimicrobial drug on four different strains of Escherichia coli (K12, R2, R3 and R4). For comparison, the same strains were tested with three types of antibiotics using the minimal inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) tests. Moreover, DNA was isolated from the analysed bacteria which was additionally digested with formamidopyrimidine-DNA glycosylase (Fpg) protein from the group of repair glycosases. These enzymes are markers of modified oxidised bases in nucleic acids produced during oxidative stress in cells. Preliminary cellular studies, MIC and MBC tests and digestion with Fpg protein after modification of bacterial DNA suggest that these compounds may have greater potential as antibacterial agents than antibiotics such as ciprofloxacin, bleomycin and cloxacillin. The described composites are highly specific for the analysed model Escherichia coli strains and may be used in the future as new substitutes for commonly used antibiotics in clinical and nosocomial infections in the progressing pandemic era. The results show much stronger antibacterial properties of the functionalised membranes on the action of bacterial membranes in comparison to the antibiotics in the Fpg digestion experiment. This is most likely due to the strong induction of oxidative stress in the cell through the breakdown of the analysed bacterial DNA. We have also observed that the intermolecular distances between the functional units play an important role for the antimicrobial properties of the used material. Hence, we utilised the idea of the 2D solvent to tailor them.


Asunto(s)
Cobre , Proteínas de Escherichia coli , Óxido de Aluminio , Antibacterianos/farmacología , Bacterias , Cobre/farmacología , ADN Bacteriano , ADN-Formamidopirimidina Glicosilasa , Escherichia coli/genética
6.
Int J Mol Sci ; 23(15)2022 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-35955950

RESUMEN

An enzymatic route for phosphorous-carbon bond formation was developed by discovering new promiscuous activity of lipase. We reported a new metal-free biocatalytic method for the synthesis of pharmacologically relevant ß-phosphonomalononitriles via a lipase-catalyzed one-pot Knoevenagel-phospha-Michael reaction. We carefully analyzed the best conditions for the given reaction: the type of enzyme, temperature, and type of solvent. A series of target compounds was synthesized, with yields ranging from 43% to 93% by enzymatic reaction with Candida cylindracea (CcL) lipase as recyclable and, a few times, reusable catalyst. The advantages of this protocol are excellent yields, mild reaction conditions, low costs, and sustainability. The applicability of the same catalyst in the synthesis of ß-phosphononitriles is also described. Further, the obtained compounds were validated as new potential antimicrobial agents with characteristic E. coli bacterial strains. The pivotal role of such a group of phosphonate derivatives on inhibitory activity against selected pathogenic E. coli strains was revealed. The observed results are especially important in the case of the increasing resistance of bacteria to various drugs and antibiotics. The impact of the ß-phosphono malonate chemical structure on antimicrobial activity was demonstrated. The crucial role of the substituents attached to the aromatic ring on the inhibitory action against selected pathogenic E. coli strains was revealed. Among tested compounds, four ß-phosphonate derivatives showed an antimicrobial activity profile similar to that obtained with currently used antibiotics such as ciprofloxacin, bleomycin, and cloxacillin. In addition, the obtained compounds constitute a convenient platform for further chemical functionalization, allowing for a convenient change in their biological activity profile. It should also be noted that the cost of the compounds obtained is low, which may be an attractive alternative to the currently used antimicrobial agents. The observed results are especially important because of the increasing resistance of bacteria to various drugs and antibiotics.


Asunto(s)
Antiinfecciosos , Organofosfonatos , Antibacterianos/farmacología , Catálisis , Escherichia coli , Lipasa/química
7.
Molecules ; 27(11)2022 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-35684570

RESUMEN

An efficient method for the synthesis of functionalized peptidomimetics via multicomponent Ugi reaction has been developed. The application of trifluoroethanol (TFE) as a reaction medium provided desired products with good yields. Further, using the developed cyclisation reaction, the obtained peptidomimetics were transformed into the cyclic analogues (diketopiperazines, DKPs). The goal of the performed studies was to revised and compare whether the structure of the obtained structurally flexible acyclic peptidomimetics and their rigid cycling analogue DKPs affect antimicrobial activity. We studied the potential of synthesized peptidomimetics, both cyclic and acyclic, as antimicrobial drugs on model E. coli bacteria strains (k12, R2-R4). The biological assays reveal that DKPs hold more potential as antimicrobial drugs compared to open chain Ugi peptidomimetics. We believe that it can be due to the rigid cyclic structure of DKPs which promotes the membrane penetration in the cell of studied pathogens. The obtained data clearly indicate the high antibiotic potential of synthesized diketopiperazine derivatives over tested antibiotics.


Asunto(s)
Antiinfecciosos , Peptidomiméticos , Antibacterianos/química , Antibacterianos/farmacología , Dicetopiperazinas/química , Escherichia coli , Peptidomiméticos/química
8.
Materials (Basel) ; 15(11)2022 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-35683150

RESUMEN

We reported a new method dealing with the synthesis of novel pharmacologically relevant α-aminophosphonate derivatives via a lipase-catalyzed Kabachnik−Fields reaction with yields of up to 93%. The advantages of this protocol are excellent yields, mild reaction conditions, low costs, and sustainability. The developed protocol is applicable to a range of H-phosphites and organic amines, providing a wide substrate scope. A new class of α-aminophosphonate analogues possessing P-chiral centers was also synthesized. The synthesized compounds were characterized on the basis of their antimicrobial activities against E. coli. The impact of the various alkoxy groups on antimicrobial activity was demonstrated. The crucial role of the substituents, located at the aromatic rings in the phenylethyloxy and benzyloxy groups, on the inhibitory action against selected pathogenic E. coli strains was revealed. The observed results are especially important because of increasing resistance of bacteria to various drugs and antibiotics.

9.
Materials (Basel) ; 15(5)2022 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-35269205

RESUMEN

An enzymatic route for phosphorous-carbon- bond formation is developed by discovering new promiscuous activity of lipase. This biocatalytic transformation of phosphorous-carbon- bond addition leads to biologically and pharmacologically relevant α-acyloxy phosphonates with methyl group in α-position. A series of target compounds were synthesized with yields ranging from 54% to 83% by enzymatic reaction with Candida cylindracea (CcL) lipase via Markovnikov addition of H-phosphites to vinyl esters. We carefully analyzed the best conditions for the given reaction such as the type of enzyme, temperature, and type of solvent. The developed protocol is applicable to a range of H-phosphites and vinyl esters significantly simplifying the preparation of synthetically challenging α-pivaloyloxy phosphonates. Further, the obtained compounds were validated as new potential antimicrobial drugs with characteristic E. coli bacterial strains and DNA modification recognized by the Fpg protein, N-methyl purine glycosylases as new substrates. The impact of the methyl group located in the α-position of the studied α-acyloxy phosphonates on the antimicrobial activity was demonstrated. The pivotal role of this group on inhibitory activity against selected pathogenic E. coli strains was revealed. The observed results are especially important in the case of the increasing resistance of bacteria to various drugs and antibiotics.

10.
Membranes (Basel) ; 12(2)2022 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-35207159

RESUMEN

Herein, we present biological studies on 3,4-dihydropyrimidin-2(1H)-ones (DHPMs) obtained via Biginelli reaction catalyzed by NH4Cl under solvent-free conditions. Until now, DHPMs have not been tested for biological activity against pathogenic E. coli strains. We tested 16 newly synthesized DHPMs as antimicrobial agents on model E. coli strains (K12 and R2-R4). Preliminary cellular studies using MIC and MBC tests and digestion of Fpg after modification of bacterial DNA suggest that these compounds may have greater potential as antibacterial agents than typically used antibiotics, such as ciprofloxacin (ci), bleomycin (b) and cloxacillin (cl). The described compounds are highly specific for pathogenic E. coli strains based on the model strains used and may be engaged in the future as new substitutes for commonly used antibiotics in clinical and nosocomial infections in the pandemic era.

11.
Materials (Basel) ; 15(4)2022 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-35207920

RESUMEN

Polyolefins are used in everyday life, including in the production of many types of plastic. In addition, polyolefins account for over 50% of the polymers produced in the world. After conducting the oligomerization reactions of 2-propen-1-ol, 2-chloro-2-propen-1-ol, and norborene, polyolefins are obtained. In this report, two complexes of oxovanadium(IV) and dioxovanadium(V) with dipicolinate, 2-phenylyridine, and 4,4'-dimethoxy-2,2'-bipyridyl as precatalysts for 2-propen-1-ol, 2-chloro-2-propen-1-ol, and norborene oligomerizations are prepared. We present for the first time the new dipicolinate complex compound of oxovanadium(IV) with 4,4'-dimetoxy-2,2'-bipyridyl. Both complexes were tested for catalytic activity in the oligomerization reactions of 2-propen-1-ol, 2-chloro-2-propen-1-ol, and norbornene. Both synthesized complexes showed high catalytic activity in these oligomerization reactions, except for the oligomerization of norbornene.

12.
Vaccines (Basel) ; 10(1)2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-35062760

RESUMEN

BACKGROUND: COVID-19 vaccines induce a differentiated humoral and cellular response, and one of the comparable parameters of the vaccine response is the determination of IgG antibodies. MATERIALS AND METHODS: Concentrations of IgG anti-SARS-CoV-2 antibodies were analyzed at three time points (at the beginning of May, at the end of June and at the end of September). Serum samples were obtained from 954 employees of the Nicolaus Copernicus University in Torun (a total of three samples each were obtained from 511 vaccinated participants). IgG antibody concentrations were determined by enzyme immunoassay. The statistical analysis included comparisons between vaccines, between convalescents and COVID-19 non-patients, between individual measurements and included the gender, age and blood groups of participants. RESULTS: There were significant differences in antibody levels between mRNA and vector vaccines. People vaccinated with mRNA-1273 achieved the highest levels of antibodies, regardless of the time since full vaccination. People vaccinated with ChAdOx1 nCoV-2019 produced several times lower antibody levels compared to the mRNA vaccines, while the antibody levels were more stable. In the case of each of the vaccines, the factor having the strongest impact on the level and stability of the IgG antibody titers was previous SARS-CoV-2 infection. There were no significant correlations with age, gender and blood type. SUMMARY: mRNA vaccines induce a stronger humoral response of the immune system with the fastest loss of antibodies over time.

13.
Neuroradiology ; 62(7): 843-849, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32253455

RESUMEN

PURPOSE: The aim of this study is to use functional magnetic resonance (fMRI) to analyse the cortical presentation of selected language functions in patients after a total laryngectomy. METHODS: Eighteen patients after total laryngectomy treated with electrolarynx speech and 18 volunteers were included. The mean number of patients' post-operative speech rehabilitation sessions was five (range of 3-8 sessions). Four paradigms were used, including noun generation, pseudoword reading, reading phrases with pseudowords, and nonliteral sign reproduction. RESULTS: In noun, the most significant difference between the groups was the stronger activation of both lingual gyri in the volunteers. Pseudoword reading resulted in stronger activations in patients than in volunteers in the lingual gyri, the right cerebellum, the right Broca's area, and the right parietal operculum. Reading phrases with pseudowords involved different parts of the Brodmann area 40. During nonliteral sign reproduction, there was a stronger activation of the left Broca's area in volunteers and a stronger activation of the left premotor cortex in patients. CONCLUSION: This study provides evidence of altered cortical activation in response to language tasks in patients after a laryngectomy compared with healthy volunteers, which may be considered brain plasticity in response to a laryngectomy.


Asunto(s)
Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Laringectomía , Imagen por Resonancia Magnética/métodos , Plasticidad Neuronal , Medición de la Producción del Habla , Femenino , Humanos , Laringe Artificial , Masculino , Persona de Mediana Edad , Psicolingüística
14.
J Comput Assist Tomogr ; 43(6): 857-862, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31738209

RESUMEN

OBJECTIVE: The objective of this study is to compare the value of monoexponential and biexponential approach to the diffusion-weighted magnetic resonance imaging signal in the prediction of the liver fibrosis. METHODS: Forty patients with hepatitis C were included. Quantification of the apparent diffusion coefficient (ADC) and pure molecular diffusion (D), pseudodiffusion (D*), and perfusion fraction (f) was performed using 9 b values (b = 0, 20, 50, 100, 200, 400, 600, 800, 1000 s/mm). RESULTS: Significant fibrosis was found in 14 subjects. Monoexponentally derived ADC parameters were significantly correlated. Apparent diffusion coefficient calculated from all b values and ADC based on high b values were significantly related to the fibrosis grade (P < 0.02), and none of intravoxel incoherent motion parameters presented such an association. Apparent diffusion coefficient based on high b values was the best predictor of significant fibrosis with area under the curve of 0.81, sensitivity of 0.57, and specificity of 0.92. CONCLUSION: Intravoxel incoherent motion parameters did not allow for prediction of the liver fibrosis. Apparent diffusion coefficient calculated based on high b values presents considerable specificity in predicting significant fibrosis.


Asunto(s)
Hepatitis C/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador/métodos , Cirrosis Hepática/diagnóstico por imagen , Adulto , Anciano , Imagen de Difusión por Resonancia Magnética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , Adulto Joven
15.
Neuroradiology ; 61(5): 585-593, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30877333

RESUMEN

PURPOSE: A combination of the caloric test with functional magnetic resonance imaging (fMRI) is a promising method for a comprehensive diagnostics of pathologies of the vestibular system. The aim of this study was to investigate the potential pattern of grey matter local activation in fMRI using cold and hot caloric stimulation in patients presenting unilateral peripheral vestibular injury. METHODS: Forty right-handed participants aged 27 to 56 with the diagnosis of right-sided peripheral vestibular hypofunction were included. Stimulation was performed separately for the right and the left ear with cold (C, 14-15 °C) stimulus and hot (H, 48-49 °C) stimulus. Grey matter activation was assessed in BOLD technique using a 3T scanner. RESULTS: We observed activity within the parieto-insular vestibular cortex (PIVC), thalamus, insula and retroinsular area, hippocampus, and cerebellum, as well as oculomotor centers located in the precentral gyrus, superior temporal gyrus, and intraparietal sulcus. Cold stimulus resulted in more areas of activation in response to the right ear activation rather than to the left ear. The ipsilateral activity was noted for insular cortex and intraparietal sulcus. The differences between hot and cold stimuli were noted for the right ear. CONCLUSIONS: In this preliminary study, the combination of the caloric test and fMRI allowed to present specific pattern of grey matter activation in patients with unilateral peripheral vestibular injury. Further studies are necessary to develop patterns or cortical maps differentiating various balance disorders and to analyze the dynamics of cortical plasticity after the injury.


Asunto(s)
Pruebas Calóricas , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/fisiopatología , Imagen por Resonancia Magnética , Enfermedades Vestibulares/fisiopatología , Adulto , Femenino , Lateralidad Funcional/fisiología , Humanos , Masculino , Persona de Mediana Edad
16.
Colloids Surf B Biointerfaces ; 108: 212-8, 2013 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-23584361

RESUMEN

Phospholipids are the main components of biological membranes. The aim of the present study was to determine the influence of a cationic surfactant on phospholipid structure and dynamics. Fourier transform infrared (FTIR) and dielectric relaxation (DRS) spectroscopies as well as small-angle X-ray scattering (SAXS) with synchrotron radiation have been used to analyse the structure of fully hydrated 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) in the presence of a quaternary ammonium surfactant: (benzyloxymethyl) dodecyldimethylammoniumchloride (BzMDDAC). The presence of the surfactant caused changes in the temperature of the DMPC phase transition, as revealed using FTIR and DRS measurements. This change results from the disappearance of the multilamellar phase of DMPC and the formation of the unilamellar (most likely bicellar) phase, as indicated by the SAXS results.


Asunto(s)
Compuestos de Benzalconio/química , Dimiristoilfosfatidilcolina/química , Tensoactivos/química , Cationes , Membranas Artificiales , Transición de Fase , Dispersión del Ángulo Pequeño , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Difracción de Rayos X
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