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1.
Ann Clin Transl Neurol ; 10(10): 1824-1832, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37553799

RESUMO

BACKGROUND/OBJECTIVES: Several studies have shown a relationship between vitamin D and migraine, including the association between decreased serum 25-hydroxyvitamin D in patients with migraine and the positive effects of vitamin D supplementations in the therapy of this disease. Two single-nucleotide variants (SNVs) vitamin D receptor (VDR) gene, VDR rs2228570, and VDR rs731236 have shown an association with migraine risk in a previous case-control association study, while an exome sequencing study identified a rare variant in GC vitamin D binding protein gene. This study aims to look for the association between several common variants in these two genes and the risk for migraine. METHODS: We genotyped 290 patients diagnosed with migraine and 300 age-matched controls using specific TaqMan assays for VDR rs2228570, VDR rs731236, VDR rs7975232, VDR rs739837, VDR rs78783628, GC rs7041, and GC rs4588 SNVs. RESULTS: We did not find an association between these SNVs and the risk for migraine. None of these SNVs were related to the positivity of a family history of migraine or with the presence of aura. The VDR rs731236A allele showed a significant association with the triggering of migraine attacks by ethanol (Pc = 0.007). CONCLUSIONS: In summary, the results of the current study suggest a lack of association between common SNVs in the VDR and GC gene and the risk of developing migraine. The possible relationship between VDR rs731236 and the triggering of migraine episodes with ethanol deserves future studies.


Assuntos
Polimorfismo de Nucleotídeo Único , Receptores de Calcitriol , Humanos , Receptores de Calcitriol/genética , Vitamina D , Genótipo , Etanol
2.
Phys Chem Chem Phys ; 25(30): 20473-20484, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37431774

RESUMO

Prebiotic chemistry one-pot reactions, such as HCN-derived polymerizations, have been used as stimulating starting points for the generation of new multifunctional materials due to the simplicity of the processes, use of water as solvent, and moderate thermal conditions. Slight experimental variations in this special kind of polymerization tune the final properties of the products. Thus, herein, the influence of NH4Cl on the polymerization kinetics of cyanide under hydrothermal conditions and on the macrostructures and properties of this complex system is explored. The kinetics of the process is consistent with an autocatalytic model, but important variations in the polymerization reaction are observed according to a simple empirical model based on a Hill equation. The differences in the kinetic behaviour against NH4Cl were also revealed when the structural, morphological, thermal, electronic and magnetic properties of the synthesized cyanide polymers were compared, and these properties were evaluated by elemental analysis, FTIR, XPS, UV-vis, and ESR spectroscopies, X-ray diffraction, SEM and thermoanalytical techniques. As a result, this hydrothermal prebiotic polymerization is not only pH dependent, as previously thought, but also ammonium subservient. From this result, a hypothetical reaction mechanism was proposed, which involves the active participation of ammonium cations via formamidine and serves as a remarkable point against previous reports. The results discussed here expand the knowledge on HCN wet chemistry, offer an extended view of the relevant parameters during the simulation of hydrothermal scenarios and describe the production of promising paramagnetic and semiconducting materials inspired by prebiotic chemistry.

3.
Polymers (Basel) ; 15(3)2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36771787

RESUMO

Aminomalononitrile (AMN), the HCN formal trimer, is a molecule of interest in prebiotic chemistry, in fine organic synthesis, and, currently, in materials science, mainly for bio-applications. Herein, differential scanning calorimetry (DSC) measurements by means of non-isothermal experiments of the stable AMN p-toluenesulfonate salt (AMNS) showed successful bulk AMN polymerization. The results indicated that this thermally stimulated polymerization is initiated at relatively low temperatures, and an autocatalytic kinetic model can be used to appropriately describe, determining the kinetic triplet, including the activation energy, the pre-exponential factor, and the mechanism function (Eα, A and f(α)). A preliminary structural characterization, by means of Fourier transform infrared (FTIR) spectroscopy, supported the effective generation of HCN-derived polymers prepared from AMNS. This study demonstrated the autocatalytic, highly efficient, and straightforward character of AMN polymerization, and to the best of our knowledge, it describes, for the first time, a systematic and extended kinetic analysis for gaining mechanistic insights into this process. The latter was accomplished through the help of simultaneous thermogravimetry (TG)-DSC and the in situ mass spectrometry (MS) technique for investigating the gas products generated during these polymerizations. These analyses revealed that dehydrocyanation and deamination processes must be important elimination reactions involved in the complex AMN polymerization mechanism.

4.
Int J Mol Sci ; 24(2)2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36674807

RESUMO

Several papers have been published suggesting a probable role of inflammatory factors in the etiopathogenesis of migraine. In this study, we investigated the possible association between common variants in the LAG3/CD4 genes (both genes, which are closely related, encode proteins involved in inflammatory and autoimmune responses) in the risk of migraine in a cohort of Caucasian Spanish participants. For this purpose, the frequencies of CD4 rs1922452, CD4 rs951818, and LAG3 rs870849 genotypes and allelic variants, using a specific TaqMan-based qPCR assay, were assessed in 290 patients diagnosed with migraine and in 300 healthy controls. The relationship of these variables with several clinical features of migraine was also analyzed. The frequencies of the analyzed LAG3/CD4 genotypes did not differ significantly between the two study groups and were not related to the sex, age at onset of migraine, family history of migraine, presence or absence of aura, or the triggering effect of ethanol on migraine episodes. These results suggest a lack of association between common variants in the LAG3/CD4 genes and the risk of developing migraine in the Caucasian Spanish population.


Assuntos
Antígenos CD4 , Predisposição Genética para Doença , Proteína do Gene 3 de Ativação de Linfócitos , Transtornos de Enxaqueca , Humanos , Genótipo , Transtornos de Enxaqueca/genética , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Antígenos CD4/genética , Proteína do Gene 3 de Ativação de Linfócitos/genética
5.
Polymers (Basel) ; 15(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36679288

RESUMO

For the first time, chemometrics was applied to the recently reported microwave-driven cyanide polymerization. Fast, easy, robust, low-cost, and green-solvent processes are characteristic of these types of reactions. These economic and environmental benefits, originally inspired by the constraints imposed by plausible prebiotic synthetic conditions, have taken advantage of the development of a new generation of HCN-derived multifunctional materials. HCN-derived polymers present tunable properties by temperature and reaction time. However, the apparently random behavior observed in the evolution of cyanide polymerizations, assisted by microwave radiation over time at different temperatures, leads us to study this highly complex system using multivariate analytical tools to have a proper view of the system. Two components are sufficient to explain between 84 and 98% of the total variance in the data in all principal component analyses. In addition, two components explain more than 91% of the total variance in the data in the case of principal component analysis for categorical data. These consistent statistical results indicate that microwave-driven polymerization is a more robust process than conventional thermal syntheses but also that plausible prebiotic chemistry in alkaline subaerial environments could be more complex than in the aerial part of these systems, presenting a clear example of the "messy chemistry" approach of interest in the research about the origins of life. In addition, the methodology discussed herein could be useful for the data analysis of extraterrestrial samples and for the design of soft materials, in a feedback view between prebiotic chemistry and materials science.

6.
Int J Mol Sci ; 23(23)2022 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-36499121

RESUMO

According to several studies, inflammatory factors could be related to the pathogenesis of idiopathic restless legs syndrome (RLS). In addition, RLS and Parkinson's disease (PD) have shown a possible relationship, and recent studies have shown an association between CD4 rs1922452 and CD4 rs951818 single nucleotide variants (SNVs) and the risk for PD. For these reasons, we investigated the possible association between common variants in the LAG3/CD4 genes (which encoded proteins involved in inflammatory and autoimmune responses) and the risk for RLS in a Caucasian Spanish population. We assessed the frequencies of CD4 rs1922452, CD4 rs951818, and LAG3 rs870849 genotypes and allelic variants in 285 patients with idiopathic RLS and 350 healthy controls using a specific TaqMan-based qPCR assay. We also analyzed the possible influence of the genotypes' frequencies on several variables, including age at onset of RLS, gender, family history of RLS, and response to drugs commonly used in the treatment of RLS. We found a lack of association between the frequencies of genotypes and allelic variants of the 3 SNVs studied and the risk of RLS, and a weak though significant association between the CD4 rs1922452 GG genotype and an older age at onset of RLS. With the exception of this association, our findings suggest that common SNVs in the CD4/LAG3 genes are not associated with the risk of developing idiopathic RLS in Caucasian Spanish people.


Assuntos
Antígenos CD4 , Proteína do Gene 3 de Ativação de Linfócitos , Doença de Parkinson , Síndrome das Pernas Inquietas , Humanos , Alelos , Genótipo , Doença de Parkinson/genética , Polimorfismo de Nucleotídeo Único , Síndrome das Pernas Inquietas/genética , Síndrome das Pernas Inquietas/epidemiologia , Fatores de Risco , Antígenos CD4/genética , Proteína do Gene 3 de Ativação de Linfócitos/genética
8.
Sci Rep ; 12(1): 15140, 2022 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-36071125

RESUMO

Herein, the potential of alkaline hydrothermal environments for the synthesis of possible ancestral pre-RNA nucleobases using cyanide as a primary source of carbon and nitrogen is described. Water cyanide polymerizations were assisted by microwave radiation to obtain high temperature and a relatively high pressure (MWR, 180 °C, 15 bar) and were also carried out using a conventional thermal system (CTS, 80 °C, 1 bar) to simulate subaerial and aerial hydrothermal conditions, respectively, on the early Earth. For these syntheses, the initial concentration of cyanide and the diffusion effects were studied. In addition, it is well known that hydrolysis conditions are directly related to the amount and diversity of organic molecules released from cyanide polymers. Thus, as a first step, we studied the effect of several hydrolysis procedures, generally used in prebiotic chemistry, on some of the potential pre-RNA nucleobases of interest, together with some of their isomers and/or deamination products, also presumably formed in these complex reactions. The results show that the alkaline hydrothermal scenarios with a relatively constant pH are good geological scenarios for the generation of noncanonical nucleobases using cyanide as a prebiotic precursor.


Assuntos
Planeta Terra , RNA , Cianetos , Geologia , RNA/química , Água/química
9.
Polymers (Basel) ; 14(17)2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36080535

RESUMO

The polymers based on diaminomaleonitrile (DAMN polymers) are a special group within an extensive set of complex substances, namely HCN polymers (DAMN is the formal tetramer of the HCN), which currently present a growing interest in materials science. Recently, the thermal polymerizability of DAMN has been reported, both in an aqueous medium and in bulk, offering the potential for the development of capacitors and biosensors, respectively. In the present work, the polymerization of this plausible prebiotic molecule has been hydrothermally explored using microwave radiation (MWR) via the heating of aqueous DAMN suspensions at 170-190 °C. In this way, polymeric submicron particles derived from DAMN were obtained for the first time. The structural, thermal decomposition, and electrochemical properties were also deeply evaluated. The redox behavior was characterized from DMSO solutions of these highly conjugated macromolecular systems and their potential as semiconductors was described. As a result, new semiconducting polymeric submicron particles were synthetized using a very fast, easy, highly robust, and green-solvent process. These results show a new example of the great potential of the polymerization assisted by MWR associated with the HCN-derived polymers, which has a dual interest both in chemical evolution and as functional materials.

10.
Clin Cancer Res ; 28(20): 4536-4550, 2022 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-35921524

RESUMO

PURPOSE: PARP inhibitors (PARPi) induce synthetic lethality in homologous recombination repair (HRR)-deficient tumors and are used to treat breast, ovarian, pancreatic, and prostate cancers. Multiple PARPi resistance mechanisms exist, most resulting in restoration of HRR and protection of stalled replication forks. ATR inhibition was highlighted as a unique approach to reverse both aspects of resistance. Recently, however, a PARPi/WEE1 inhibitor (WEE1i) combination demonstrated enhanced antitumor activity associated with the induction of replication stress, suggesting another approach to tackling PARPi resistance. EXPERIMENTAL DESIGN: We analyzed breast and ovarian patient-derived xenoimplant models resistant to PARPi to quantify WEE1i and ATR inhibitor (ATRi) responses as single agents and in combination with PARPi. Biomarker analysis was conducted at the genetic and protein level. Metabolite analysis by mass spectrometry and nucleoside rescue experiments ex vivo were also conducted in patient-derived models. RESULTS: Although WEE1i response was linked to markers of replication stress, including STK11/RB1 and phospho-RPA, ATRi response associated with ATM mutation. When combined with olaparib, WEE1i could be differentiated from the ATRi/olaparib combination, providing distinct therapeutic strategies to overcome PARPi resistance by targeting the replication stress response. Mechanistically, WEE1i sensitivity was associated with shortage of the dNTP pool and a concomitant increase in replication stress. CONCLUSIONS: Targeting the replication stress response is a valid therapeutic option to overcome PARPi resistance including tumors without an underlying HRR deficiency. These preclinical insights are now being tested in several clinical trials where the PARPi is administered with either the WEE1i or the ATRi.


Assuntos
Antineoplásicos , Neoplasias Ovarianas , Antineoplásicos/uso terapêutico , Proteínas Mutadas de Ataxia Telangiectasia , Proteína BRCA1/genética , Biomarcadores , Carcinoma Epitelial do Ovário/tratamento farmacológico , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Feminino , Humanos , Nucleosídeos/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Ftalazinas/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo
11.
Antioxidants (Basel) ; 11(2)2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35204155

RESUMO

Increased brain and serum zinc levels in patients with idiopathic restless legs syndrome (idiopathic RLS or iRLS) were described when compared with controls, suggesting a possible role of zinc in the pathogenesis of this disease. However, serum magnesium, calcium, manganese, iron, and copper levels of RLS patients were similar to controls, suggesting a specific impairment of zinc-dependent metabolism in RLS. The aim of this study is to assess the serum concentrations of trace elements involved in oxidative stress or causing peripheral nerve toxicity in a large series of patients with iRLS and controls. We determined serum levels of iron, copper, manganese, zinc, magnesium, selenium, calcium, aluminium, lead, cadmium, arsenic and mercury in 100 patients diagnosed with iRLS and in 110 age- and sex-matched controls using Inductively Coupled Plasma Mass Spectrometry. Serum copper, magnesium, selenium, and calcium concentrations were significantly higher in RLS patients than in controls. These differences were observed both in men and women. There were no major correlations between serum trace metal concentrations and age at onset of RLS or RLS severity, nor was there any association with a family history of RLS or drug response. This study shows an association between increased serum concentrations of copper, magnesium, selenium, and calcium with RLS in a Spanish Caucasian population and does not confirm the previously reported increase in serum zinc concentrations in patients suffering from this disease, suggesting that the different accuracy of the analytical methods used could have influenced the inconsistent results found in the literature.

12.
Eur J Clin Invest ; 52(6): e13757, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35113457

RESUMO

BACKGROUND/OBJECTIVES: Histamine has shown a possible role in the etiopathogenesis of migraine. It has been reported an association between some polymorphisms in the diamine oxidase (DAO) gene and migraine, especially in women. Two studies addressing DAO activity in migraine patients showed conflicting results. We investigated the possible relationship of serum DAO activity and histamine levels and 3 polymorphisms in the DAO gene with the risk for migraine. METHODS: We studied the frequencies of DAO rs10156191, rs1049742 and rs1049793 genotypes and allelic variants in 298 migraine patients and 360 healthy controls (using a TaqMan-based qPCR assay), and serum DAO activity and histamine levels in a subset of 99 migraine patients and 115 controls with strict exclusion criteria, and analysed the relationship of these variables with several clinical features of migraine. RESULTS: The frequencies of the DAO genotypes and allelic variants analysed were similar in migraine patients and controls. Serum DAO activity was significantly higher in migraine patients (Vmax/Km 4.24 ± 2.93 vs. 3.60 ± 7.64, p < 0.001), especially in females (Vmax/Km 4.63 ± 2.96 vs. 3.18 ± 2.32, p < 0.0001), while serum histamine was similar in both study groups. CONCLUSION: Serum DAO activity was increased in patients with migraine, especially in females, while serum histamine levels were normal. None of the studied polymorphisms was associated with the risk for migraine.


Assuntos
Amina Oxidase (contendo Cobre) , Transtornos de Enxaqueca , Amina Oxidase (contendo Cobre)/genética , Feminino , Genótipo , Histamina , Humanos , Transtornos de Enxaqueca/genética , Polimorfismo de Nucleotídeo Único
13.
Life (Basel) ; 11(7)2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34357033

RESUMO

Hydrogen cyanide, HCN, is considered a fundamental molecule in chemical evolution. The named HCN polymers have been suggested as precursors of important bioorganics. Some novel researches have focused on the role of mineral surfaces in the hydrolysis and/or polymerization of cyanide species, but until now, their role has been unclear. Understanding the role of minerals in chemical evolution processes is crucial because minerals undoubtedly interacted with the organic molecules formed on the early Earth by different process. Therefore, we simulated the probable interactions between HCN and a serpentinite-hosted alkaline hydrothermal system. We studied the effect of serpentinite during the thermolysis of HCN at basic conditions (i.e., HCN 0.15 M, 50 h, 100 °C, pH > 10). The HCN-derived thermal polymer and supernatant formed after treatment were analyzed by several complementary analytical techniques. The results obtained suggest that: (I) the mineral surfaces can act as mediators in the mechanisms of organic molecule production such as the polymerization of HCN; (II) the thermal and physicochemical properties of the HCN polymer produced are affected by the presence of the mineral surface; and (III) serpentinite seems to inhibit the formation of bioorganic molecules compared with the control (without mineral).

14.
Front Pharmacol ; 12: 618989, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33732155

RESUMO

Because nitric oxide and endothelial dysfunction could play a role in the pathogenesis of idiopathic restless legs syndrome (RLS), as was suggested by some preliminary data, we investigated the possible association between the rs2070744 variants in the endothelial nitric oxide synthase (eNOS or NOS3) gene (chromosome 7q36.1) and the risk for RLS in a Caucasian Spanish population. We assessed the frequencies of NOS3 single nucleotide polymorphisms (SNPs) rs2070744, rs1799983, and rs79467411 genotypes and allelic variants in 273 patients with idiopathic RLS and 325 healthy controls using a TaqMan-based qPCR assay. We also analyzed the possible influence of genotype frequency on age at onset of RLS symptoms, gender, family history of RLS, and response to drugs commonly used in the treatment of RLS such as dopaminergic drugs, clonazepam, and GABAergic drugs. The frequencies of genotypes and allelic variants were not associated with the risk for RLS and were not influenced by gender, age, and positive family history of RLS. We identified weak statistical associations of the SNP rs1799983 with the response to dopamine agonists (Pc = 0.018 for the rs1799983 G/T genotype) and of the SNP rs79467411 with the response to clonazepam (Pc = 0.018 for the rs79467411 G allele), although these findings should be cautiously interpreted and require further confirmation. These associations aside, our findings suggest that common NOS3 SNPs are not associated with the risk for idiopathic RLS in Caucasian Spanish people.

16.
J Neurol ; 268(4): 1461-1472, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33219423

RESUMO

BACKGROUND/OBJECTIVES: Several studies showed lower serum 25-hydroxyvitamin D levels in patients with idiopathic restless legs syndrome (RLS) compared with matched controls, and a single study showed an association between the rs731236 single nucleotide polymorphism (SNP) in the vitamin D receptor (VDR) gene and the risk for RLS. We aimed to study the relationship between the serum 25-hydroxyvitamin D levels and to confirm previous findings related to SNPs in the VDR and the GC vitamin D binding protein (GC) gene, with the risk for RLS in the Spanish Caucasian population. METHODS: We genotyped 285 idiopathic RLS patients and 325 age and sex-matched controls for VDRrs2228750, VDRrs7975232, VDRrs739837, VDRrs78783628, GCrs7041 and GCrs4588 SNPs using TaqMan assays, and determined serum 25-hydroxyvitamin D levels in 111 idiopathic RLS patients and 167 controls using an ELISA commercial kit. RESULTS: Serum 25-hydroxyvitamin D levels were significantly higher in RLS patients than in controls but were unrelated with the 7 SNPs studied. None of the 7 SNPs analyzed was associated with the risk for idiopathic RLS or with a positive family history of RLS. However, RLS patients carrying the rs7975232CC genotype or the rs7975232C allele, had a higher frequency of response to GABAergic drugs. Associations between the age at onset and the severity of RLS with SNPs were inconsistent. CONCLUSIONS: This study shows an association between increased serum concentrations of 25-hydroxyvitamin D and a lack of association between 7 SNPs in the VDR and in the GC genes with RLS in the Spanish Caucasian population.


Assuntos
Receptores de Calcitriol , Síndrome das Pernas Inquietas , Proteínas de Transporte , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Receptores de Calcitriol/genética , Síndrome das Pernas Inquietas/genética , Vitamina D
17.
Polymers (Basel) ; 14(1)2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-35012081

RESUMO

A systematic study is presented to explore the NH4CN polymerization induced by microwave (MW) radiation, keeping in mind the recent growing interest in these polymers in material science. Thus, a first approach through two series, varying the reaction times and the temperatures between 130 and 205 °C, was conducted. As a relevant outcome, using particular reaction conditions, polymer conversions similar to those obtained by means of conventional thermal methods were achieved, with the advantage of a very significant reduction of the reaction times. The structural properties of the end products were evaluated using compositional data, spectroscopic measurements, simultaneous thermal analysis (STA), X-ray diffraction (XRD), and scanning electron microscopy (SEM). As a result, based on the principal component analysis (PCA) from the main experimental results collected, practically only the crystallographic features and the morphologies in the nanoscale were affected by the MW-driven polymerization conditions with respect to those obtained by classical syntheses. Therefore, MW radiation allows us to tune the morphology, size and shape of the particles from the bidimensional C=N networks which are characteristic of the NH4CN polymers by an easy, fast, low-cost and green-solvent production. These new insights make these macromolecular systems attractive for exploration in current soft-matter science.

18.
RSC Adv ; 11(33): 20109-20117, 2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35479901

RESUMO

Traditionally, the effect of mineral surfaces on increasing molecular complexity has been considered a major issue in studies about the origin of life. In contrast, herein, the effects of organic films derived from cyanide over an important prebiotic mineral, pyrite, are considered. An XPS spectroscopy study was carried out to understand the surface chemistry of the HCN-derived polymer/pyrite system. As a result, the simulation of a plausible prebiotic alkaline hydrothermal environment led to the identification of an NH4CN-based film with protective corrosion properties that immediately prevented the oxidation of the highly reactive pyrite surface. In addition, the effect of coating with antioxidant properties was preserved over a relatively long time, and the polymeric film was very stable under ambient conditions. These results increase the great potential of HCN polymers for development as a cheap and easily produced new class of multifunctional polymeric materials that also show promising and attractive insights into prebiotic chemistry.

19.
Sci Rep ; 10(1): 22350, 2020 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-33339853

RESUMO

In this paper, the first study on NH4CN polymerization induced by microwave radiation is described, where a singular kinetic behaviour, especially when this reaction is conducted in the absence of air, is found. As a result, a complex conjugated N-heterocyclic polymer system is obtained, whose properties are very different, and even improved according to morphological features, characterized by their X-ray diffraction patterns and scanning electron microscopy analysis, with respect to those produced under conventional thermal treatment. In addition, a wide variety of relevant bioorganics have been identified, such as amino acids, nucleobases, co-factors, etc., from the synthetized NH4CN polymers. These particular families of polymers are of high interest in the fields of astrobiology and prebiotic chemistry and, more recently, in the development of smart multifunctional materials. From an astrobiological perspective, microwave-driven syntheses may simulate hydrothermal environments, which are considered ideal niches for increasing organic molecular complexity, and eventually as scenarios for an origin of life. From an industrial point of view and for potential applications, a microwave irradiation process leads to a notable decrease in the reaction times, and tune the properties of these new series macromolecular systems. The characteristics found for these materials encourage the development of further systematic research on this alternative HCN polymerization.

20.
Pharmacogenomics J ; 20(3): 426-432, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31792366

RESUMO

Because nitric oxide could play an important role in the pathogenesis of migraine (suggested by experimental, neuropathological, biochemical, and pharmacological data), and a recent meta-analysis showed an association between the single-nucleotide polymorphism (SNP) rs2070744 in the endothelial nitric oxide synthase (eNOS or NOS3) gene (chromosome 7q36.1) and the risk for migraine in Caucasians, we attempted to replicate the possible association between this SNP and the and the risk for migraine in the Caucasian Spanish population. The frequencies for the NOS3 rs2070744 genotypes and allelic variants were assessed in 283 migraine patients and 287 healthy controls with a TaqMan-based qPCR Assay. The putative influence on genotype frequency of age at onset of migraine attacks, gender, family history of migraine, absence or presence of aura, and triggering of migraine attacks by ethanol, were also analyzed. The frequencies of NOS3 rs2070744 genotypes and allelic variants were not associated with the risk for migraine (OR [95%] CI for the minor allele = 0.91 [0.72-1.15]) and were not influenced by age at onset of migraine, gender, presence of aura, or triggering of migraine attacks by ethanol. NOS3 rs2070744CC genotypes were significantly more frequent in patients with a family history of migraine. NOS3 rs2070744 SNP is not associated with the risk for migraine in Caucasian Spanish people although it might be related to family history.


Assuntos
Predisposição Genética para Doença/genética , Variação Genética/genética , Transtornos de Enxaqueca/genética , Óxido Nítrico Sintase Tipo III/genética , Adolescente , Adulto , Idoso , Feminino , Estudos de Associação Genética/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos de Enxaqueca/enzimologia , Fatores de Risco , Adulto Jovem
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