One‑ and two‑dimensional carbon nanomaterials as adsorbents of cationic and anionic dyes from aqueous solutions

E. E. Pérez‑Ramírez,M. de la Luz‑Asunción,A. L. Martínez‑Hernández,G. de la Rosa‑Álvarez,S. Fernández‑Tavizón,P. Salas,C. Velasco‑Santos 한국탄소학회 2019 Carbon Letters Vol.29 No.2

One- and two-dimensional carbon nanomaterials were tested as adsorbents for the elimination of two anionic dyes, reactive red 2 and methyl orange, and the cationic dye methylene blue from aqueous solutions under the same conditions. Carbon nanomaterials performed well in the removal of dyes. Surface oxygenated groups in the nanomaterials improved the cationic dyes’ adsorption, but not the adsorption of the anionic dye. The interactions between nanomaterials and dyes were verified by infrared and Raman spectroscopy. The pseudo-second order kinetic model was better fitted to the kinetic experimental data than the Elovich and pseudo-first order models. The equilibrium adsorption data were best fitted by the Langmuir model. The dimensions and morphology of the carbon nanomaterials play an important role in the adsorption of the three dyes. The main mechanism of adsorption of anionic dyes is by the interactions of the aromatic rings of the dye structures and π delocalized electrons on carbon nanostructures; the adsorption of cationic dye is mainly due to electrostatic interactions.

Blockchain Technology for Sustainable Supply Chains: A Bibliometric Study

Javier RAMÍREZ(Javier RAMÍREZ ),Girlesa GALLEGO(Girlesa GALLEGO ),William NIEBLES-NÚÑEZ(William NIEBLES-NÚÑEZ ),Johny García TIRADO(Johny García TIRADO ) 한국유통과학회 2023 유통과학연구 Vol.21 No.6

CtIP interacts with TopBP1 and Nbs1 in the response to double-stranded DNA breaks (DSBs) in Xenopus egg extracts.

Ramí,rez-Lugo, Juan S,Yoo, Hae Yong,Yoon, Su Jin,Dunphy, William G Landes Bioscience 2011 Cell cycle Vol.10 No.3

<P>In the presence of double-stranded DNA breaks (DSBs), the activation of ATR is achieved by the ability of ATM to phosphorylate TopBP1 on serine 1131, which leads to an enhancement of the interaction between ATR and TopBP1. In Xenopus egg extracts, the Mre11-Rad50-Nbs1 (MRN) complex is additionally required to bridge ATM and TopBP1 together. In this report, we show that CtIP, which is recruited to DSB-containing chromatin, interacts with both TopBP1 and Nbs1 in a damage-dependent manner. An N-terminal region containing the first two BRCT repeats of TopBP1 is essential for the interaction with CtIP. Furthermore, two distinct regions in the N-terminus of CtIP participate in establishing the association between CtIP and TopBP1. The first region includes two adjacent putative ATM/ATR phosphorylation sites on serines 273 and 275. Secondly, binding is diminished when an MRN-binding region spanning residues 25-48 is deleted, indicative of a role for the MRN complex in mediating this interaction. This was further evidenced by a decrease in the interaction between CtIP and TopBP1 in Nbs1-depleted extracts and a reciprocal decrease in the binding of Nbs1 to TopBP1 in the absence of CtIP, suggestive of the formation of a complex containing CtIP, TopBP1, and the MRN complex. When CtIP is immunodepleted from egg extracts, the activation of the response to DSBs is compromised and the levels of ATR, TopBP1, and Nbs1 on damaged chromatin are reduced. Thus, CtIP interacts with TopBP1 in a damage-stimulated, MRN-dependent manner during the activation of ATR in response to DSBs.</P>

Intron 4 VNTR (4a/b) Polymorphism of the Endothelial Nitric Oxide Synthase Gene Is Associated with Breast Cancer in Mexican Women

Ramírez-Patiño Ramiro,Figuera Luis Eduardo,Puebla-Pérez Ana María,Delgado-Saucedo Jorge Ivan,Legazpi-Macias María Magdalena,Mariaud-Schmidt Rocio Patricia,Ramos-Silva Adriana,Gutiérrez-Hurtado Itzae A 대한의학회 2013 Journal of Korean medical science Vol.28 No.11

The endothelial nitric oxide synthase (eNOS) gene plays an important role in several biological functions. Polymorphisms of the eNOS gene have been associated with cancer. It has been suggested that the VNTR 4 a/b polymorphism may affect the expression of eNOS and contributes to tumor promotion in the mammary gland. We examined the role of the eNOS4 a/b polymorphism by comparing the genotypes of 281 healthy Mexican women with the genotypes of 429 Mexican women with breast cancer (BC). The observed genotype frequencies for control and BC patients were 0.6% and 0.7% for a/a (polymorphic); 87% and 77% for a/a (wild type); and 12% and 22% for a/b respectively. We found that the odds ratio (OR) was 1.9, with a 95% confidence interval (95%CI) of 1.29-2.95, P=0.001 for genotypes a/a-a/b, b/c. The association was also evident when comparing the distribution of the a/a-a/b genotypes in patients with high levels of glutamate-oxaloacetate transaminase (SGOT) (OR, 1.93; 95% CI, 1.14-3.28; P=0.015); undergoing menopause with high levels of SGOT (OR, 2.0; 95% CI, 1.1-3.84); and with high levels of glutamic-pyruvic transaminase (SGPT) (OR, 3.5; 95% CI, 1.56-8.22). The genotypes a/a-a/b are associated with BC susceptibility in the analyzed samples from the Mexican population.

Chimeric Myostatin - Tetanic Toxin Epitopes and Heterologous Prime-boost Immunization Improve Immune Response Stimulating Muscle Growth in Mice

Vianey Ramírez Andoney,Amanda Gayosso Vázquez,Juan Pablo Pintor Ríos,Jorge Enrique Vázquez Buchelli,Rogelio A. Alonso Morales 한국생물공학회 2019 Biotechnology and Bioprocess Engineering Vol.24 No.5

Myostatin is a transforming growth factor-β family member who acts as a negative regulator of skeletal muscle growth. The interference of its biological activity could increase skeletal muscle growth with clinical and animal production applications. A strategy to block the myostatin action is by the induction of an immune response against it. In this work, we evaluated as an immunogen a recombinant myostatin fused to the tetanic toxin T- helper epitopes P2 and P30. Genetic constructs of the chimeric myostatin were cloned in an expression vector and used as a DNA vaccine. Besides, a chimeric genetic construct, P2-miostatin–P30 was expressed in Escherichia coli, obtaining a recombinant chimeric antigen. To find out the functionality of these genetic constructs as a vaccine in inducing muscle growth responses, experimental groups of BALB/c mice were DNA immunized with the myostatin fused to P2, P30 or both. Furthermore, to improve the immune response, a heterologous prime–boost immunization scheme was evaluated where the DNA inoculation was followed by immunization with the recombinant antigen P2-myostatin-P30. The different body segments weight was recorded in control and vaccinated mice groups, finding increased muscle masses in the vaccinated groups. These experiments showed the effectiveness of the P2 and P30 Thelper epitopes in inducing an immune response to the fused myostatin, leading to muscle growth. The heterologous prime-boost immunization protocol is a promising vaccination strategy reducing the time and amount of antigen used to induce a immune response to myostatin.

Particle size effect of LiAlSiO₄on the thermal expansion of SiC porous materials

I. Juárez-Ramírez,K. Matsumaru,K. Ishizaki,L.M. Torres-Martínez 한양대학교 세라믹연구소 2008 Journal of Ceramic Processing Research Vol.9 No.5

This paper reports the effect of the particle size of LiAlSiO4 on the thermal expansion and Young’s modulus of low thermal expansion (LTE) coefficient of porous materials using silicon carbide (SiC), vitrified bonding material (VBM) and lithium aluminum silicate (LiAlSiO4) at 850 oC. According to the XRD results, there is no reaction between the raw materials during the sintering process. SEM analysis revealed the presence of an internal porous structure with a pore size less than 4 micrometers. It was found that decreasing the particle size of LiAlSiO4 by almost 4 times reduces the porosity, keeping a low thermal expansion coefficient, but the Young’s modulus increases 50%. This paper reports the effect of the particle size of LiAlSiO4 on the thermal expansion and Young’s modulus of low thermal expansion (LTE) coefficient of porous materials using silicon carbide (SiC), vitrified bonding material (VBM) and lithium aluminum silicate (LiAlSiO4) at 850 oC. According to the XRD results, there is no reaction between the raw materials during the sintering process. SEM analysis revealed the presence of an internal porous structure with a pore size less than 4 micrometers. It was found that decreasing the particle size of LiAlSiO4 by almost 4 times reduces the porosity, keeping a low thermal expansion coefficient, but the Young’s modulus increases 50%.

Giant Lipoma of the Breast

Luis Ramírez-Montaño,Erik Vargas-Tellez,Walid L Dajer-Fadel,Silvia Espinosa Maceda 대한성형외과학회 2013 Archives of Plastic Surgery Vol.40 No.3

Lipomas are benign mesenchymal tumors that develop in areas of abundant adipose tissue. Due to the fatty composition of the breast, difficulties in diagnosis, treatment, and reconstruction are often encountered. We report a case of a 55-year-old female with a giant tumor of the right breast that comprised most of its mass, causing breast asymmetry. A thorough preoperative evaluation, followed by an uneventful difficult surgical resection and reconstruction, resulted in diagnosis of a benign lipoma. The case prompted this report because of its challenging size,location, diagnosis, and reconstructive solution.

Active Disturbance Rejection Control of the Inertia Wheel Pendulum through a Tangent Linearization Approach

Mario Ramírez-Neria,Hebertt Sira-Ramírez,Rubén Garrido-Moctezuma,Alberto Luviano-Juárez 제어·로봇·시스템학회 2019 International Journal of Control, Automation, and Vol.17 No.1

A flatness based approach is proposed for the linear Active Disturbance Rejection Control (ADRC) stabilizationof a nonlinear inertia wheel pendulum (IWP) around its unstable equilibrium point, subject to unmodelleddynamics and disturbances. The approach exploits the cascade structure, provided by the flatness property, of thetangent linearization of the underactuated system which allows designing a high gain linear cascaded Extended StateObserver (ESO) of the Generalized Proportional Integral (GPI) type. This class of linear observers is employed tobuild an Active Disturbance Rejection Control controller with a lower order of complexity regarding other ADRCclassic schemes. Experimental results demonstrate the effectiveness and feasibility of the proposed approach, aswell as a better behavior with respect to a classic control technique in the presence of disturbances.

COVID-19 vaccination policies and the new challenges of international travel

Céleo Ramírez,최준낙,Reyna M. Durón 대한백신학회 2022 Clinical and Experimental Vaccine Research Vol.11 No.2

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Challenges managing COVID vaccine-induced immune thrombotic thrombocytopenia in low-middle income countries

Céleo Ramírez,Ramón Jeremías Soto Hernández,Reyna M. Durón 대한백신학회 2021 Clinical and Experimental Vaccine Research Vol.10 No.3

Vaccine-induced immune thrombotic thrombocytopenia (VITT) is an extremely rare complication associated with the adenovirus-vectored coronavirus disease 2019 (COVID-19) ChAdOx1 nCoV-19 (AZD1222) vaccine. It is characterized by venous thrombosis, mainly cerebral venous sinus thrombosis, moderate to severe thrombocytopenia, and rarely, thrombosis in cerebral arteries. This syndrome is similar to the heparin-induced thrombocytopenia and presents mostly among women aged 18–55 years, without previous exposure to heparin, usually 5 to 20 days after vaccination. However, cases have been reported in men and older adults [1-4]. Unlike COVID-19, this adverse effect might not represent a public health problem in itself, but it is already causing vaccine hesitancy in population groups susceptible to severe COVID-19, and poses a challenge in low resource settings [5]. The first case reports showed evidence that VITT has a mortality around 40% [1-3]. So far, cases have been reported and treated in hospitals of highly developed countries with first-rate health systems that facilitate early detection and treatment of this severe adverse event. VITT is confirmed by using PF4-dependent enzyme-linked immunosorbent assay (ELISA) assay, which allows the differential diagnosis from other causes of thrombosis in patients with a history of ChAdOx1 nCoV-19 vaccination in previous days. However, it is likely that a large number of hospitals in many low-middle income countries do not have approved PF4-dependent ELISA assays for accurate diagnosis, nor immunoglobulins, glucocorticoids, and non-heparin anticoagulants needed for the treatment of this condition [1-4]. In times of this COVID-19 pandemic and precision medicine, problems and solutions should be considered global. Policies related to COVID-19 need to be addressed considering varied public health and socioeconomic contexts. The ChAdOx1 nCoV-19 vaccine is one of the most used vaccines in low-middle income countries, where special testing to confirm VITT is not widely available. Therefore, real figures are unknown, and underreporting of this adverse effect should be considered. Patient information, government, and hospital preparedness in these countries are needed to diagnose and manage VITT adequately, and to reduce morbidity and mortality from this complication. These strategies will have a positive impact on public acceptance and adherence to COVID vaccination.