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1.
PLoS One ; 17(7): e0264566, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35901034

RESUMEN

Current medical guidelines consider pregnant women with COVID-19 to be a high-risk group. Since physiological gestation downregulates the immunological response to maintain "maternal-fetal tolerance", SARS-CoV-2 infection may constitute a potentially threatening condition to both the mother and the fetus. To establish the immune profile in pregnant COVID-19+ patients, a cross-sectional study was conducted. Pregnant women with COVID-19 (P-COVID-19+; n = 15) were analyzed and compared with nonpregnant women with COVID-19 (NP-COVID-19+; n = 15) or those with physiological pregnancy (P-COVID-19-; n = 13). Serological cytokine and chemokine concentrations, leucocyte immunophenotypes, and mononuclear leucocyte responses to polyclonal stimuli were analyzed in all groups. Higher concentrations of serological TNF-α, IL-6, MIP1b and IL-4 were observed within the P-COVID-19+ group, while cytokines and chemokines secreted by peripheral leucocytes in response to LPS, IL-6 or PMA-ionomicin were similar among the groups. Immunophenotype analysis showed a lower percentage of HLA-DR+ monocytes in P-COVID-19+ than in P-COVID-19- and a higher percentage of CD39+ monocytes in P-COVID-19+ than in NP-COVID-19+. After whole blood polyclonal stimulation, similar percentages of T cells and TNF+ monocytes between groups were observed. Our results suggest that P-COVID-19+ elicits a strong inflammatory response similar to NP-COVID19+ but also displays an anti-inflammatory response that controls the ATP/adenosine balance and prevents hyperinflammatory damage in COVID-19.


Asunto(s)
COVID-19 , Monocitos , Apirasa/inmunología , Estudios Transversales , Citocinas , Femenino , Humanos , Interleucina-6 , Embarazo , SARS-CoV-2
2.
Biophys Rev (Melville) ; 3(3): 031401, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38505279

RESUMEN

The nanoscale organization of functional (bio)molecules on solid substrates with nanoscale spatial resolution and single-molecule control-in both position and orientation-is of great interest for the development of next-generation (bio)molecular devices and assays. Herein, we report the fabrication of nanoarrays of individual proteins (and dyes) via the selective organization of DNA origami on nanopatterned surfaces and with controlled protein orientation. Nanoapertures in metal-coated glass substrates were patterned using focused ion beam lithography; 88% of the nanoapertures allowed immobilization of functionalized DNA origami structures. Photobleaching experiments of dye-functionalized DNA nanostructures indicated that 85% of the nanoapertures contain a single origami unit, with only 3% exhibiting double occupancy. Using a reprogrammed genetic code to engineer into a protein new chemistry to allow residue-specific linkage to an addressable ssDNA unit, we assembled orientation-controlled proteins functionalized to DNA origami structures; these were then organized in the arrays and exhibited single molecule traces. This strategy is of general applicability for the investigation of biomolecular events with single-molecule resolution in defined nanoarrays configurations and with orientational control of the (bio)molecule of interest.

3.
RSC Adv ; 11(49): 31073-31083, 2021 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-35498913

RESUMEN

A theoretical study of the Mn trimer adsorbed on the noble metal surfaces Au(111) and Cu(111) is reported. The calculations were performed using first-principles methods within the density functional theory and the generalized gradient approximation in the collinear and non-collinear magnetic phases. The system was modeled by considering a surface unit cell of 25 atoms to improve the trimer's isolation on the surface. We evaluated the trimer as a linear chain and forming triangular structures. The triangular trimer can be adsorbed in two possible configurations, above an empty surface triangle site (Δ) or on a triangle with a surface atom at the center in a hexagonal structure (H). The difference is the coordination of the Mn with surface atoms. We studied the antiferromagnetic (AF), ferromagnetic (FM), and non-collinear (NC) magnetic cases. As a result, the lowest energy configuration on both metals is the AFΔ configuration, which has an isosceles triangle shape. In comparison, the NC and the FM configurations adopt an equilateral geometry. The same trend was observed for the H configurations, but they are less bonded. The results are supported by calculating the spin-polarized electronic structure and the electronic charge transfer. Finally, we computed the energy barriers that inhibit the transformation of the linear chain to a delta Mn trimer on both substrates.

4.
Rev Gastroenterol Mex (Engl Ed) ; 84(3): 372-397, 2019.
Artículo en Inglés, Español | MEDLINE | ID: mdl-31213326

RESUMEN

INTRODUCTION: Non-cardiac chest pain is defined as a clinical syndrome characterized by retrosternal pain similar to that of angina pectoris, but of non-cardiac origin and produced by esophageal, musculoskeletal, pulmonary, or psychiatric diseases. AIM: To present a consensus review based on evidence regarding the definition, epidemiology, pathophysiology, and diagnosis of non-cardiac chest pain, as well as the therapeutic options for those patients. METHODS: Three general coordinators carried out a literature review of all articles published in English and Spanish on the theme and formulated 38 initial statements, dividing them into 3 main categories: (i)definitions, epidemiology, and pathophysiology; (ii)diagnosis, and (iii)treatment. The statements underwent 3rounds of voting, utilizing the Delphi system. The final statements were those that reached >75% agreement, and they were rated utilizing the GRADE system. RESULTS AND CONCLUSIONS: The final consensus included 29 statements. All patients presenting with chest pain should initially be evaluated by a cardiologist. The most common cause of non-cardiac chest pain is gastroesophageal reflux disease. If there are no alarm symptoms, the initial approach should be a therapeutic trial with a proton pump inhibitor for 2-4weeks. If dysphagia or alarm symptoms are present, endoscopy is recommended. High-resolution manometry is the best method for ruling out spastic motor disorders and achalasia and pH monitoring aids in demonstrating abnormal esophageal acid exposure. Treatment should be directed at the pathophysiologic mechanism. It can include proton pump inhibitors, neuromodulators and/or smooth muscle relaxants, psychologic intervention and/or cognitive therapy, and occasionally surgery or endoscopic therapy.


Asunto(s)
Dolor en el Pecho/terapia , Dolor en el Pecho/diagnóstico , Consenso , Humanos , México
5.
Pharmazie ; 74(12): 728-731, 2019 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-31907111

RESUMEN

The purpose of this research was to investigate the possible variations to the pharmacokinetics of nimesulide by the effect of age using an animal model. An experimental, analytical, prospective and longitudinal study in five dogs, from birth to 730 days of age was carried out. Nimesulide blood levels were measured in different months; concentrations were determined by HPLC-UV. Pharmacokinetic parameters were calculated by using the WinNonlin software. There were statistically significant differences (p <0.05) in most of the pharmacokinetic parameters between study of 6 months against the other three studies in different ages. Changes in the pharmacokinetic parameters of nimesulide as a result of age, are determined by the growing and maturation of the animals. Resulting data suggest that nimesulide can be used safely as a long-term analgesic in dogs, but, the dosing regimens in humans should be different when administered at early age.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacocinética , Sulfonamidas/farmacocinética , Animales , Perros , Estudios Longitudinales , Masculino , Estudios Prospectivos
6.
J Helminthol ; 93(6): 690-696, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30136641

RESUMEN

An experimental Taenia crassiceps mouse model was used to assess the role of Taenia solium metacestode factor (Fac) in human neurocysticercosis. Intraperitoneal infection with T. crassiceps metacestodes or subcutaneous inoculation with a T. crassiceps metacestode factor (Fac) produced significant impairment of performance (learning) in the Barnes maze and induced bilateral hippocampal sclerosis in mice. Several staining techniques revealed important cell dispersion, extensive apoptosis and cell loss in the dentate gyrus, hilus and CA1-CA3 regions of both hippocampi, as well as intense deterioration of the adjacent cortex. An outstanding disruption of its histoarchitecture in the surrounding tissue of all these regions and apoptosis of the endothelial cells were also observed.


Asunto(s)
Proteínas del Helminto/metabolismo , Hipocampo/parasitología , Neurocisticercosis/parasitología , Esclerosis/parasitología , Taenia/metabolismo , Teniasis/parasitología , Animales , Apoptosis , Femenino , Proteínas del Helminto/genética , Hipocampo/patología , Hipocampo/fisiopatología , Humanos , Ratones , Ratones Endogámicos BALB C , Neurocisticercosis/fisiopatología , Esclerosis/patología , Esclerosis/fisiopatología , Taenia/genética , Teniasis/patología , Teniasis/fisiopatología
7.
J Helminthol ; 91(2): 215-221, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27018714

RESUMEN

Seizures, headache, depression and neurological deficits are the signs and symptoms most frequently reported in human neurocysticercosis. However, the cause of the associated learning and memory deficits is unknown. Here, we used Taenia crassiceps infection in mice as a model of human cysticercosis. The effects of T. crassiceps metacestode infection or T. crassiceps metacestode factor (MF) treatment on mouse hippocampal cells were studied; control mice were included. At 45 days after infection or treatment of the mice with MF, all mice were anaesthetized and perfused transcardially with saline followed by phosphate-buffered 10% formalin. Then the brains were carefully removed. Coronal sections stained using several techniques were analysed. Extensive and significant apoptosis was found in the experimental animals, mainly in the dentate gyrus, CA1, CA2, CA3 and neighbouring regions, in comparison with the apparently intact cells from control mice (P < 0.01). These results suggest that neurological deficits, especially the learning and memory deficits, may be generated by extensive apoptosis of hippocampal cells.


Asunto(s)
Apoptosis , Hipocampo/citología , Neurocisticercosis/fisiopatología , Taenia/fisiología , Teniasis/fisiopatología , Animales , Femenino , Hipocampo/parasitología , Humanos , Ratones , Ratones Endogámicos BALB C , Neurocisticercosis/parasitología , Teniasis/parasitología
8.
Rev Gastroenterol Mex ; 79(2): 73-8, 2014.
Artículo en Inglés, Español | MEDLINE | ID: mdl-24878219

RESUMEN

BACKGROUND: Today, antireflux surgery has an established position in the management of gastroesophageal reflux disease. Some case series have shown good short-term results, but there is still little information regarding long-term results. Studies have recently focused on evaluating residual symptomatology and its impact on quality of life. OBJECTIVES: To determine the postoperative quality of life and degree of satisfaction in patients that underwent laparoscopic Nissen fundoplication. PATIENTS AND METHODS: A total of 100 patients (59 women and 41 men) were studied after having undergone laparoscopic Nissen fundoplication. The variables analyzed were level of satisfaction, gastrointestinal quality of life index (GIQLI), residual symptoms, and the Visick scale. RESULTS: No variation was found in relation to sex; 49 men and 51 women participated in the study. The mean age was 49 years. The degree of satisfaction encountered was: satisfactory in 81 patients, moderate in 3, and bad in 2 patients. More than 90% of the patients would undergo the surgery again or recommend it. The Carlsson score showed improvement at the end of the study (p<0.05). In relation to the GIQLI, a median of 100.61 points±21.624 was obtained. Abdominal bloating, regurgitation, and early satiety were the most frequent residual symptoms. The effect on lifestyle measured by the Visick scale was excellent. CONCLUSIONS: The level of satisfaction and quality of life obtained were comparable with reported standards; and the residual symptoms after antireflux surgery were easily controlled.


Asunto(s)
Fundoplicación/psicología , Reflujo Gastroesofágico/cirugía , Laparoscopía/psicología , Satisfacción del Paciente , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Trastornos de Deglución/epidemiología , Femenino , Reflujo Gastroesofágico/psicología , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida , Resultado del Tratamiento , Adulto Joven
9.
Artículo en Inglés | MEDLINE | ID: mdl-23485238

RESUMEN

A multi-analytical approach was used to develop a mathematical regression model to calculate the residual concentration of borate ions in water present at high initial content, as a function of the main physicochemical, mineralogical and electrokinetic characteristics after adsorption on five different types of iron and steel slag. The analytical techniques applied and slag properties obtained in this work were: X-ray Fluorescence for the identification of the main chemical compounds, X-ray Diffraction to determine crystalline phases, physical adsorption of nitrogen for the quantification of textural properties and zeta-potential for electrokinetic measurements of slag particles. Adsorption tests were carried out using the bottle-point technique and a highly concentrated borate solution (700 mg B/L) at pH 10, with a slag dose of 10 g/L. An excellent correlation between the residual concentration of boron and three independent variables (content of magnesium oxide, zeta potential and specific surface area) was established for the five types of slag tested in this work. This shows that the methodology based on a multi-analytical approach is a very strong and useful tool to estimate the performance of iron and steel slag as adsorbent of metalloids.


Asunto(s)
Residuos Industriales , Metaloides/análisis , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/análisis , Adsorción , Boro/química , Fluorescencia , Hierro , Metaloides/química , Metaloides/aislamiento & purificación , Metalurgia , Oxidación-Reducción , Acero , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Difracción de Rayos X
10.
J Phys Condens Matter ; 22(50): 505302, 2010 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-21406793

RESUMEN

Armchair carbon nanoribbons (ACNRs) substitutionally doped with boron atoms are investigated in the framework of first-principles density functional theory. Different boron-boron arrangements and concentrations are considered in order to simulate possible aggregation patterns, their structural stability and electronic behavior are determined as a function of ribbon size. In agreement with previous studies, our results show that the dopant atoms have in general a preference for edge sites, but specific effects appear as a function of concentration that importantly modify the properties of the ribbons compared to the pristine case. Interesting tendencies are discovered as a function of dopant concentration that significantly affect the electronic properties of the ribbons. We have found that BC(3) island formation and edge doping are the most important factors for the structural stabilization of the ribbons with high boron concentration (>7%) whereas for the cases of low boron concentrations (<5%) the structural stabilities are similar. For all the doped cases, we have found that the BC(3) island patterns give rise to highly localized B states on top of the Fermi level, resulting in semiconducting behavior. On the other hand, when the average distance between the B atoms increases beyond island stoichiometry, the localization of their states is reduced and the ribbons may become metallic due to a band crossing caused by the lowering of the Fermi level resulting from the positive charge doping. Thus, tuning the dopant interaction would be an appropriate way to tailor the electronic properties of the ribbons in a convenient manner in view of potential technological applications.

11.
Hernia ; 13(3): 233-8, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19225858

RESUMEN

BACKGROUND: The use of open tension-free techniques in hernia surgery seems to be superior to those techniques that apply tension to the suture line. However, the cost-effectiveness of tension vs. tension-free repairs has not been investigated before. METHODS: This study is a cost-effectiveness analysis within a randomized controlled clinical trial that compared open-tension (OT) versus mesh-plug tension-free (MPTF) hernia repair, with a 2-year follow-up for each patient. Between July 2002 and June 2003, 106 patients with inguinal hernia were randomized to either procedure. Main outcome measures included average surgical time, time to full recovery, pain visual analog scale, amount of analgesics required, off-work time, hospital stay, and heath-care costs. RESULTS: The average cost was $885.15 (95% CI $843.56-$926.74) and $837.66 (95% CI $796.42-878.89) USD for the OT and the MPTF herniorrhaphy, respectively (P < 0.05). Average yearly savings with the MPTF repair were calculated as $7,598.84 USD. Surgery time, time to full recovery, pain visual-analog scale, use of analgesics, off-work time, and hospital stay were significantly lower for the MPTF repair. Disability-adjusted life-years were reduced 56% with the MPTF repair, which represented a total savings of $12,656.60 USD with this procedure. CONCLUSION: This controlled clinical trial demonstrates that the MPTF technique significantly decreases care costs in patients operated on for inguinal hernias.


Asunto(s)
Hernia Inguinal/cirugía , Procedimientos Quirúrgicos Operativos/economía , Procedimientos Quirúrgicos Operativos/métodos , Adulto , Anciano , Análisis Costo-Beneficio , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mallas Quirúrgicas
12.
Acta Chir Belg ; 106(5): 541-4, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17168266

RESUMEN

PURPOSE: The purpose of this study is to compare the safety and complications of direct trocar insertion without pneumoperitoneum (DTI) with Veress needle (VN) in laparoscopic cholecystectomy (LC). METHODS: We studied 84 patients admitted to our hospital for LC, in a random simple blind design, 42 patients were assigned to DTI and 42 to VN. The variables analysed were : procedure complications, laparoscope insertion time and duration of surgery. RESULTS: Complication percentages between the groups were significantly different (DTI 2.3% versus VN 23.8%, p = 0.009). The duration of surgery between the two groups was also significantly different (DTI 56+/-31 versus VN 71+/-28 minutes, p < 0.02). Finally, laparoscope insertion time between the two techniques was significantly different (DTI 1.5+/-0.5 versus VN 3.0+/-0.4 minutes p < 0.001). CONCLUSIONS: Our results show DTI to be a safe, efficient, rapid and easily-learned alternative technique, reducing the number of procedure-related complications.


Asunto(s)
Colecistectomía Laparoscópica/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Factores de Tiempo
13.
Biochim Biophys Acta ; 1757(12): 1614-22, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16934215

RESUMEN

In highly aerobic environments, Gluconacetobacter diazotrophicus uses a respiratory protection mechanism to preserve nitrogenase activity from deleterious oxygen. Here, the respiratory system was examined in order to ascertain the nature of the respiratory components, mainly of the cyanide sensitive and resistant pathways. The membranes of G. diazotrophicus contain Q(10), Q(9) and PQQ in a 13:1:6.6 molar ratios. UV(360 nm) photoinactivation indicated that ubiquinone is the electron acceptor for the dehydrogenases of the outer and inner faces of the membrane. Strong inhibition by rotenone and capsaicin and resistance to flavone indicated that NADH-quinone oxidoreductase is a NDH-1 type enzyme. KCN-titration revealed the presence of at least two terminal oxidases that were highly sensitive and resistant to the inhibitor. Tetrachorohydroquinol was preferentially oxidized by the KCN-sensitive oxidase. Neither the quinoprotein alcohol dehydrogenase nor its associated cytochromes c were instrumental components of the cyanide resistant pathway. CO-difference spectrum and photodissociation of heme-CO compounds suggested the presence of cytochromes b-CO and a(1)-CO adducts. Air-oxidation of cytochrome b (432 nm) was arrested by concentrations of KCN lower than 25 microM while cytochrome a(1) (442 nm) was not affected. A KCN-sensitive (I(50)=5 microM) cytochrome bb and a KCN-resistant (I(50)=450 microM) cytochrome ba quinol oxidases were separated by ion exchange chromatography.


Asunto(s)
Grupo Citocromo b/metabolismo , Gluconacetobacter/metabolismo , Proteínas Bacterianas/metabolismo , Coenzimas , Cianuros/farmacología , Grupo Citocromo b/antagonistas & inhibidores , Farmacorresistencia Bacteriana , Gluconacetobacter/efectos de los fármacos , NADH Deshidrogenasa/metabolismo , Oxidorreductasas/metabolismo , Ubiquinona/análogos & derivados , Ubiquinona/metabolismo
14.
IEE Proc Nanobiotechnol ; 152(2): 73-84, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16441161

RESUMEN

The encapsulation of molecular species has received considerable attention in recent years. Polymers, dendrimers and microemulsions along with other systems have been used as precursors for the synthesis of encapsulating agents. Especially important in this field is the core-shell architecture. This structure offers the encapsulated species an extra level of protection due to the presence of a shell, covering the interior of a capsule. Dyes, porphyrines, drugs, cells and other active agents have been successfully encapsulated, and the host-guest interaction has been studied by various experimental techniques. A review is new provided of the progress made in this field in the last several years is presented. Different classes of synthetic approaches are presented and resulting encapsulation studies are summarised. An approach to the encapsulation of dansyl chloride dye in core-shell nanoparticles is also presented.


Asunto(s)
Materiales Biocompatibles Revestidos/química , Cristalización/métodos , Portadores de Fármacos/química , Colorantes Fluorescentes/química , Nanoestructuras/química , Nanoestructuras/ultraestructura , Nanotecnología/métodos , Portadores de Fármacos/síntesis química , Ensayo de Materiales , Microscopía Fluorescente/métodos , Nanotecnología/instrumentación , Tamaño de la Partícula , Espectrometría de Fluorescencia/métodos
18.
Neurosci Lett ; 56(3): 271-7, 1985 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-3927201

RESUMEN

The baseline efflux of gamma-amino[2,3-3H]butyric acid ([3H]GABA) and [3H]dopamine ([3H]DA) from caudate synaptosomes was greatly enhanced by the sodium-ionophore monensin; this stimulatory effect of monensin on transmitter release was markedly inhibited by trifluoperazine (TFP), a potent calmodulin antagonist. TFP also decreased the depolarization-induced, calcium-dependent release of [3H]GABA and this effect was unrelated to the calcium-flux across the plasma membrane since TFP also inhibited the release of GABA elicited by the calcium-ionophore A23187. Our data indicate that transmitter release induced by both increased intraterminal sodium levels and by the calcium entry into the nerve endings during depolarization might be mediated by calmodulin-dependent processes.


Asunto(s)
Calmodulina/farmacología , Dopamina/metabolismo , Sodio/farmacología , Sinaptosomas/metabolismo , Ácido gamma-Aminobutírico/metabolismo , Animales , Química Encefálica/efectos de los fármacos , Calcimicina/farmacología , Núcleo Caudado/efectos de los fármacos , Monensina/farmacología , Cloruro de Potasio/farmacología , Ratas , Factores de Tiempo , Trifluoperazina/farmacología , Veratrina/farmacología
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