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1.
Arch Suicide Res ; : 1-12, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37204142

RESUMO

OBJECTIVE: The main aim of the current study was to investigate whether SKA2 gene expression in the postmortem brain of rs7208505 genotype are altered in suicide victims from a Mexican population. METHODS: In this study, we report a genetic analysis of expression levels of the SKA2 gene in the prefrontal cortex of the postmortem brain of suicidal subjects (n = 22) compared to subjects who died of causes other than suicide (n = 22) in a Mexican population using RT-qPCR assays. Additionally, we genotyped the rs7208505 polymorphism in suicide victims (n = 98) and controls (n = 88) and we evaluate the association of genotypes for the SNP rs7208505 with expression level of SKA2. RESULTS: The results showed that the expression of the SKA2 gene was significantly higher in suicide victims compared to control subjects (p = 0.044). Interestingly, we observed a greater proportion of allele A of the rs7208505 in suicide victims than controls. Even though there was no association between the SNP with suicide in the study population we found a significative association of the expression level from SKA2 with the allele A of the rs7208505 and suicide. CONCLUSION: The evidence suggests that the expression of SKA2 in the prefrontal cortex may be a critical factor in the etiology of suicidal behavior.


HighlightsSuicide victims have a higher level of SKA2 gene expression in the brain's prefrontal cortex than control subjects.The SKA2 rs7208505 is not associated with suicide in the Mexican population studied.Allele frequencies for G are higher than allele frequencies for A in our study population.The allele A of the rs7208505 affects the expression values of the SKA2 gene.

2.
Neurosci Lett ; 778: 136611, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35364128

RESUMO

OBJECTIVE: The main aim of the current study was to investigate whether the expression levels of the HTR2A and MAOA genes are altered in the postmortem brain of suicide victims from Mexican population. METHODS: On the basis of a case- control study, we examined the expression levels of HTR2A and MAOA genes in the postmortem prefrontal cortex (Brodmann area 8/9) and hypothalamus (ventromedial nucleus) tissues from 20 suicide victims and 20 control subjects from a Mexican population. Gene-expression profile quantification was carried out by qPCR and determined by the 2-ΔΔCt method. RESULTS: In suicide victims, the expression levels of the HTR2A gene were significantly higher in the prefrontal cortex. In contrast, the expression of the MAOA gene in the hypothalamus of the suicide victims was significantly higher than in the control subjects. These results were consistent regardless of age, sex, postmortem interval, or pH of brain tissue. CONCLUSION: The evidence suggests that the pattern of differential expression of HTR2A and MAOA genes in the brain may be involved in suicide, providing a possible molecular basis for the brain abnormalities in suicide victims.


Assuntos
Suicídio , Encéfalo/metabolismo , Estudos de Casos e Controles , Humanos , Hipotálamo , Córtex Pré-Frontal/metabolismo
3.
Oxid Med Cell Longev ; 2020: 3970860, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33110472

RESUMO

N-aryl maleimides can undergo a 1,4-Michael-type addition reaction with reduced glutathione (GSH), leading to a decreased concentration of GSH and an increased concentration of free radicals (FRs) in cells. GSH is a critical scavenging molecule responsible for protecting cells from oxidation and for maintaining redox homeostasis. N-aryl maleimides disturb redox homeostasis in cells because they scavenge thiol-containing molecules, especially GSH. This study aimed at measuring the concentrations of GSH and FRs by electronic paramagnetic resonance (EPR), in the brain and liver tissue of male Wistar rats (ex vivo) at different ages and after treatment with 3,5-dimaleimylbenzoic acid (3,5-DMB). Our results showed a relationship between age and the concentrations of GSH and FRs in cells. In young rats, the concentration of GSH was higher than in old rats, while the concentration of FRs was higher in adult rats than in young rats, suggesting an inverse relationship between GSH and FRs. On the other hand, the reaction of 3,5-DMB (an electrophilic maleimide) with cellular GSH increased the FR content. The results of this study contribute to the awareness that the process of aging implies not only a loss of tissue function but also essential changes in the molecular contents of cells, especially the concentrations of FRs and GSH.


Assuntos
Envelhecimento , Radicais Livres/metabolismo , Glutationa/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres/química , Glutationa/química , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Maleimidas/farmacologia , Modelos Biológicos , Oxirredução , Ratos , Ratos Wistar
4.
Dalton Trans ; 49(35): 12432-12440, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32851997

RESUMO

Two novel semiconducting coordination oligomers with 1D chain structures, namely [H0.07 CuI0.65CuII0.14(µ-p-CNC6H4CO2)·0.9H2O]n and [Ag(µ-p-CNC6H4CO2)]n, were obtained and characterized by XRD powder patterns, and XPS, EPR, UV-vis-NIR, IR and Raman spectroscopy. According to XRD analysis, CuICuII-ICNBA is an amorphous solid, while AgI-ICNBA crystalizes with a monoclinic unit cell in the C2/c space group (Z = 4). The composition and further information of CuICuII-ICNBA were obtained from the spectroscopic data. In correspondence with the quantification of terminal groups from high-resolution XPS spectra, CuICuII-ICNBA and AgI-ICNBA are composed of an average of 9 and 7 monomer units, respectively, resulting in 1D-oligomers. The spectroscopic evidence indicates that CuICuII-ICNBA is better described as a non-stoichiometric coordination oligomer (where non-integer ratios of metal ions can be accommodated), while AgI-ICNBA is stoichiometric. In both materials, each metal center is linked by two µ-η1:η1-p-isocyanobenzoate ligands forming microfibers of around 120 nm (CuICuII-material) and 310 nm (AgI-material) in average diameters with optical band gaps of 2.60 eV and 2.17 eV, respectively.

5.
ACS Omega ; 4(27): 22521-22529, 2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31909335

RESUMO

In the present manuscript, we report the kinetic and spectroscopic analysis of six new pinch-porphyrins: protoporphyrin-picpenta 1, mesoporphyrin-picpenta 2, deuteroporphyrin-picpenta 3, protoporphyrin-picocta 4, mesoporphyrin-picocta 5, and deuteroporphyrin-picocta 6. The Michaelis-Menten enzymatic pathway and the guaiacol test confirmed the ability of the compounds to function like new peroxidase models. UV-vis, 1H NMR, and electron spin resonance studies are in accordance with porphyrin-Fe(III) molecules with the quantum phenomena called quantum mixed spin (qms, s = 3/2, s = 5/2). Importantly, the influence of the presence of the s = 3/2 spin state in the compounds and its critical role for the catalytic capacity is proven here, which was the original hypothesis in our research group. The compounds with higher populations of the s = 3/2 spin state have increased peroxidase activity.

6.
Cambios rev. méd ; 15(2): 56-60, jul. 2016. ilus
Artigo em Espanhol | LILACS | ID: biblio-1000270

RESUMO

Introducción: La compresión medular (CM) por neplasia es una de las complicaciones neurológicas con más morbilidad seguido por metástasis cerebrales. Considerada una emergencia oncológica, porque puede llevar a la pérdida irreversible de la función neurológica si no se realiza un diagnóstico oportuno y se inicia un tratamiento adecuado. La invasión del cuerpo vertebral por diseminación hematógena, es la causa más frecuente y en ocasiones llega a crear inestabilidad mecánica vertebral que supone una verdadera urgencia ortopédica. El dolor es el síntoma más precoz y frecuente. Caso: Se analizan las características clínicas, patológicas, factores pronósticos y manejo de la CM por cáncer, en una paciente femenina de 73 años con cuadro de dolor cervical de 8 meses de evolución más déficit motor reciente en miembros superiores y signos radiológicos de compresión medular cervical y resultados de estabilización quirúrgica. Discusión: Los signos y síntomas van apareciendo a medida que el proceso avanza, pasando por la debilidad motora, alteración en la sensibilidad hasta llegar a la parálisis e incontinencia de esfínteres, como consecuencia del daño neurológico completo. La exploración complementaria más importante es la Resonancia Magnética Nuclear (RMN) que debe ser solicitada de inmediato para decidir e iniciar el tratamiento. El tratamiento es individualizado y debe de instaurarse con precocidad. El tratamiento estándar por muchos años ha sido radioterapia; actualmente se han implementado nuevas técnicas de radiación y de cirugía que ofrecen buenos resultados.


Introduction: Spinal cord compression secondary to neoplasia is a commonn neurological complication that raises morbidity, only followed by brain metastases. It is considered an oncologic emergency since it can lead to an irreversible loss of neurological function. Haematogenous invasion of the vertebral body is the commonest cause of spinal cord compression. Occassionally, it can cause vertebral instability which represents a real orthopedic emergency. Pain is the earliest and most common symptom.. Case: The clinical, pathological, prognostic factors and management of spinal cord compression due to cáncer in a female patient of 73 years with neck pain box 8 months duration + recent motor deficit upper limbs + radiographic signs of cervical cord compression are analyzed and surgical stabilization results. Discusion: Signs and symptoms appear when the problem progresses as motor weakness, alterations in consciousness, paralysis and incontinence, as a result of complete neurological damage. The most important complementary exploration is Magnetic Resonance Imaging (MRI) that should be requested to decide immediately and initiate treatment. The standard treatment for many years was radiotherapy; currently there are new techniques of radiation and surgery that offer good results.


Assuntos
Humanos , Feminino , Idoso , Compressão da Medula Espinal , Cervicalgia , Oncologia , Metástase Neoplásica , Coluna Vertebral , Morbidade , Neurologia
7.
Molecules ; 21(7)2016 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-27355940

RESUMO

The spectroscopic and kinetic characterization of two intermediates from the H2O2 oxidation of three dimethyl ester [(proto), (meso), (deuteroporphyrinato) (picdien)]Fe(III) complexes ([FePPPic], [FeMPPic] and [FeDPPic], respectively) pinch-porphyrin peroxidase enzyme models, with s = 5/2 and 3/2 Fe(III) quantum mixed spin (qms) ground states is described herein. The kinetic study by UV/Vis at λmax = 465 nm showed two different types of kinetics during the oxidation process in the guaiacol test for peroxidases (1-3 + guaiacol + H2O2 → oxidation guaiacol products). The first intermediate was observed during the first 24 s of the reaction. When the reaction conditions were changed to higher concentration of pinch-porphyrins and hydrogen peroxide only one type of kinetics was observed. Next, the reaction was performed only between pinch-porphyrins-Fe(III) and H2O2, resulting in only two types of kinetics that were developed during the first 0-4 s. After this time a self-oxidation process was observed. Our hypotheses state that the formation of the π-cation radicals, reaction intermediates of the pinch-porphyrin-Fe(III) family with the ligand picdien [N,N'-bis-pyridin-2-ylmethyl-propane-1,3-diamine], occurred with unique kinetics that are different from the overall process and was involved in the oxidation pathway. UV-Vis, ¹H-NMR and ESR spectra confirmed the formation of such intermediates. The results in this paper highlight the link between different spectroscopic techniques that positively depict the kinetic traits of artificial compounds with enzyme-like activity.


Assuntos
Ferro/química , Peroxidase/química , Peroxidase/metabolismo , Porfirinas/química , Análise Espectral , Peróxido de Hidrogênio/química , Cinética , Estrutura Molecular , Oxirredução , Análise Espectral/métodos
8.
Neurochem Res ; 39(11): 2093-104, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25096900

RESUMO

It is well known that the principal biomolecules involved in Alzheimer's disease (AD) are acetylcholinesterase (AChE), acetylcholine (ACh) and the amyloid beta peptide of 42 amino acid residues (Aß42). ACh plays an important role in human memory and learning, but it is susceptible to hydrolysis by AChE, while the aggregation of Aß42 forms oligomers and fibrils, which form senile plaques in the brain. The Aß42 oligomers are able to produce hydrogen peroxide (H2O2), which reacts with metals (Fe(2+), Cu(2+), Cr(3+), Zn(2+), and Cd(2+)) present at high concentrations in the brain of AD patients, generating the hydroxyl radical ((·)OH) via Fenton (FR) and Fenton-like (FLR) reactions. This mechanism generates high levels of free radicals and, hence, oxidative stress, which has been correlated with the generation and progression of AD. Therefore, we have studied in vitro how AChE catalytic activity and ACh levels are affected by the presence of metals (Fe(3+), Cu(2+), Cr(3+), Zn(2+), and Cd(2+)), H2O2 (without Aß42), and (·) OH radicals produced from FR and FLR. The results showed that the H2O2 and the metals do not modify the AChE catalytic activity, but the (·)OH radical causes a decrease in it. On the other hand, metals, H2O2 and (·)OH radicals, increase the ACh hydrolysis. This finding suggests that when H2O2, the metals and the (·)OH radicals are present, both, the AChE catalytic activity and ACh levels diminish. Furthermore, in the future it may be interesting to study whether these effects are observed when H2O2 is produced directly from Aß42.


Assuntos
Acetilcolinesterase/metabolismo , Biocatálise , Peróxido de Hidrogênio/farmacologia , Radical Hidroxila/metabolismo , Elementos de Transição/farmacologia , Acetilcolina/metabolismo , Peptídeos beta-Amiloides/metabolismo , Radicais Livres/metabolismo , Humanos , Hidrólise , Estresse Oxidativo/efeitos dos fármacos
9.
Biosci Rep ; 31(4): 273-82, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20883207

RESUMO

It is well known that CR (caloric restriction) reduces oxidative damage to proteins, lipids and DNA, although the underlying mechanism is unclear. However, information concerning the effect of CR on the host response to infection is sparse. In this study, 6-month-old mice that were fed AL (ad libitum) or with a CR diet were infected with Salmonella serovar Typhimurium. EPR (electron paramagnetic resonance; also known as ESR (electron spin resonance)) was used to identify FRs (free radicals). These results were subsequently correlated with SOD (superoxide dismutase) catalytic activity, iNOS [inducible NOS (nitric oxide synthase) or NOSII] expression and NO (nitric oxide) content. EPR analysis of liver samples demonstrated that there was a higher quantity of FRs and iron-nitrosyl complex in infected mice provided with a CR diet as compared with those on an AL diet, indicating that CR was beneficial by increasing the host response to Salmonella Typhimurium. Furthermore, in infected mice on the CR diet, NOSII expression was higher, NO content was greater and spleen colonization was lower, compared with mice on the AL diet. No changes in SOD activity were detected, indicating that the NO produced participated more in the formation of iron-nitrosyl complexes than peroxynitrite. These results suggest that CR exerts a protective effect against Salmonella Typhimurium infection by increasing NO production.


Assuntos
Restrição Calórica , Radicais Livres/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Infecções por Salmonella/enzimologia , Salmonella typhimurium , Animais , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico/metabolismo , Infecções por Salmonella/metabolismo , Superóxido Dismutase/metabolismo
10.
Arch. méd. Camaguey ; 13(2)mar.-abr. 2009.
Artigo em Espanhol | LILACS | ID: lil-577774

RESUMO

El embarazo postérmino a lo largo de los años ha sido motivo de angustia y preocupación familiar. Objetivo: Determinar cómo se comportó el embarazo postérmino en nuestro medio. Método: Se realizó un estudio prospectivo descriptivo y lineal en el hospital Ginecobstétrico Provincial Docente Ana Betancourt de Mora de Camagüey, de enero a diciembre de 2006. El universo y la muestra estuvieron constituidos por 100 gestantes que tuvieron este evento en las 42 semanas de embarazo y más. Resultados: Predominó el grupo etáreo entre 19 y 24 años, con un total de 35 para un 3,5 por ciento del universo, el 6,6 por ciento, no tenían experiencia previa de parto. El modo de terminación del embarazo más frecuente fue el inducido con 86, (86 por ciento), y el tipo de parto, el distócico con 53 para un 53 por ciento. La característica de líquido que predominó fue el meconial. Conclusiones: La depresión respiratoria moderada en el neonato fue la principal causa de morbilidad encontrada, seguido de la BALAM. Mientras que en las madres la enfermedad asociada al embarazo más frecuente fue la anemia ferripriva moderada.


The post-term pregnancy throughout the years has been reason of anguish and family concern. Objective: To determine how the pregnancy post-term behaved in our environment. Method: A prospective descriptive and lineal study was performed in the Provincial Educational Gynecobstetric Hospital Ana Betancourt de Mora of Camagüey, from January to December 2006. The universe and the sample were constituted by 100 pregnancy women that had this event in the 42 weeks of pregnancy and more. Results: The age group that prevailed was the one of 19 and 24 years, with a total of 35 for 3,5 percent of the universe, 6,6 percent didn't have previous experience of childbirth. The most frequent way of ending of pregnancy was the induced one with 86, (86 percent), and the childbirth type, the dystocic with 53 for 53 percent. The fluid characteristic that prevailed was the meconial. Conclusions: The moderate respiratory depression in the neonate was the main cause of morbility found, followed by BALAM. While in mothers the most frequent associated disease to pregnancy was the moderate ferripriva anemia.


Assuntos
Humanos , Feminino , Gravidez Prolongada/epidemiologia
11.
Biotechnol Lett ; 29(6): 919-24, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17450324

RESUMO

Mobil Crystalline Material (MCM-41) can be used for the immobilization of enzymes and the investigation of electron transfer in biological systems. Electron transfer between MCM-41 with aluminum (Al-MCM-41) and cytochrome P-450 (CYP2B4) was observed using electron paramagnetic resonance (EPR). When CYP2B4 was immobilized by adsorption, it catalyzed the conversion of aniline to p-aminophenol. The electron transfer was evidenced when the signal with a g value (also called g-factor or spectroscopic manifestation of the magnetic moment) of 1.98 increased at the same time that the signal with a g value 2.24 decreased due to the addition of NADPH to CYP2B4 immobilized on Al-MCM-41, indicating that FeIII was reduced to FeII. Therefore, it is possible that Al-MCM-41 participates in the electron transfer process in biological systems.


Assuntos
Sistema Enzimático do Citocromo P-450/química , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Enzimas Imobilizadas/química , Alumínio/química , Aminofenóis/química , Compostos de Anilina/química , Biotransformação , Sistema Enzimático do Citocromo P-450/metabolismo , Transporte de Elétrons , Enzimas Imobilizadas/metabolismo , Compostos Férricos/química , Compostos Férricos/farmacocinética , NADP/química , Oxirredução , Difração de Raios X
12.
Biophys Chem ; 106(3): 253-65, 2003 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-14556897

RESUMO

New complexes of the pinch-porphyrin family were obtained from the dimethylester of (proto-, meso-, and deutero-porphyrinato)iron(III) with the ligand [N,N'-bis-pyridin-2-ylmethyl-propane-1,3-diamine] 1-3 and with the ligand [N-pyridin-2-ylmethyl-N'-[3-[(pyridin-2-ylmethyl)-amino]-propyl]-propane-1,3-diamine] 4-6. The UV/VIS studies of 1-6 indicate an increase in the distortion of the ligand field excited state. The 1H NMR spectra of 1-6 at RT and over the range 223-328 K show iron(III)-complexes with quantum mixed spin state (qms) S=5/2, S=3/2. The chemical shifts of the meso protons are consistent with qms state S=3/2, S=5/2, where the S=3/2 spin state is lowest in energy. For methyl-heme the chemical shifts are also consistent with a qms state but now the S=5/2 ground state is lowest in energy. ESR spectra of 1-6 show two different species, B and C, of iron(III) with qms, S=5/2, S=3/2 consistent with the 1H NMR results. Species B with 70% of S=5/2 and species C with 72.5% of S=3/2. The catalytic activity as peroxidase of 1-6 was quantified by guaiacol test; their theoretical maximum rate constants were k(cat) approximately 10(2)-10(3) M(-1) s(-1). A quantitative empirical correlation is found: the higher the 32 spin contribution to the qms state and the higher proportion of this species into the samples, the higher the peroxidase activity. Such a correlation was also obtained for pinch-porphyrins already reported.


Assuntos
Ferro/química , Ferro/metabolismo , Peroxidase/metabolismo , Porfirinas/química , Porfirinas/metabolismo , Catálise , Espectroscopia de Ressonância de Spin Eletrônica , Compostos de Ferro/química , Compostos de Ferro/metabolismo , Cinética , Ligantes , Espectroscopia de Ressonância Magnética , Peroxidase/química , Prótons , Espectrofotometria , Termodinâmica
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