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1.
Pharmaceutics ; 16(1)2023 Dec 27.
Article in English | MEDLINE | ID: mdl-38258053

ABSTRACT

Leishmaniasis, a zoonotic parasitic disease transmitted by infected sandflies, impacts nearly 1 million people yearly and is endemic in many countries across Asia, Africa, the Americas, and the Mediterranean; despite this, it remains a neglected disease with limited effective treatments, particularly in impoverished communities with limited access to healthcare. This study aims to repurpose approved drugs for an affordable leishmaniasis treatment. After the screening of potential drug candidates by reviewing databases and utilizing molecular docking analysis, delamanid was chosen to be incorporated into solid lipid nanoparticles (SLNPs). Both in cellulo and in vivo tests confirmed the successful payload release within macrophages and through the epidermis following topical application on murine skin. The evaluation of macrophages infected with L. infantum amastigotes showed that the encapsulated delamanid exhibited greater leishmanicidal activity compared with the free drug. The process of encapsulating delamanid in SLNPs, as demonstrated in this study, places a strong emphasis on employing minimal technology, ensuring energy efficiency, cost-effectiveness, and reproducibility. It enables consistent, low-cost production of nanomedicines, even on a small scale, offering a promising step toward more accessible and effective leishmaniasis treatments.

2.
Plants (Basel) ; 11(13)2022 Jun 22.
Article in English | MEDLINE | ID: mdl-35807598

ABSTRACT

Babaco is a fast-growing herbaceous shrub with great commercial potential because of the organoleptic properties of its fruit. Babaco mosaic virus (BabMV) is a potexvirus in the family Alphaflexiviridae affecting babaco in all the provinces that produce this crop in Ecuador. BabMV was recently described but it has been affecting babaco for decades and, since many potexviruses are serologically indistinguishable, it may have been previously misidentified as papaya mosaic virus. Based on the coat protein (CP) gene, we aimed to study the distribution and epidemiological patterns of BabMV in babaco and chamburo over the years and to model its three-dimensional structure. Sequences of the CP were obtained from thirty-six isolates from plants collected in the main babaco-producing provinces of Ecuador between 2016 and 2021. The evolution rate of BabMV was estimated at 1.21 × 10-3 nucleotide substitutions site-1 year-1 and a time of origin of the most recent common ancestor around 1958.80. From molecular dynamics simulations, compared to other proteins of BabMV-RDRP, TGB1, and Alkb domain-the CP exhibited a higher flexibility with the C and N terminals as the most flexible regions. The reconstructed viral distribution provides dispersion patterns which have implications for control approaches of BabMV.

3.
Int J Biol Macromol ; 206: 1012-1025, 2022 May 01.
Article in English | MEDLINE | ID: mdl-35318078

ABSTRACT

This study aimed to evaluate the effect of incorporating different concentrations (0, 200, 300, and 400 mg L-1) of avocado peel extracts (EE-AP) on the physicochemical properties and antifungal activity of gelatin-carboxymethylcellulose (Gel-CMC) films and their applicability in berry preservation. The results showed that incorporating EE-AP was compatible with the Gel-CMC film and enhanced the mechanical properties without affecting the integrity and thermal properties. The 200 mg L-1 of EE-AP concentration on films offered the best barrier properties against water vapor (2.90 × 10-11 g m-1 s-1 Pa-1). FTIR identified the intramolecular and intermolecular interactions between the functional groups of biopolymers and the EE-AP. The results obtained revealed that EE-AP incorporation into gelatin-carboxymethylcellulose films significantly decreased the moisture content (from 12.48 to 11.02%) and solubility (from 40.13 to 35.39%) of the films. All films incorporated with EE-AP showed higher colorimetric parameters and opacity than the control film (p < 0.05). The DPPH radical scavenging ability of the Gel-CMC films was increased from 24.16 to 41.12, 57.21, and 63.47%, as the extract concentration increased. Active films presented excellent ultraviolet-visible light barrier properties. The antioxidant pigments (flavonoids and chlorophylls) were estimated spectrophotometrically through absorbance. In vitro tests indicated high effectiveness to inhibit the growth of Rhizopus stolonifer and Aspergillus niger. A preservation study indicated the absence of fungal development in berries over six days of storage. In conclusion, gelatin-carboxymethylcellulose films with EE-AP represent a potential option for active packaging and can preserve fresh fruit.


Subject(s)
Carboxymethylcellulose Sodium , Persea , Antioxidants/chemistry , Antioxidants/pharmacology , Carboxymethylcellulose Sodium/chemistry , Food Packaging/methods , Fruit , Gelatin/chemistry , Plant Extracts/chemistry , Plant Extracts/pharmacology
4.
Int J Biol Macromol ; 122: 1173-1183, 2019 Feb 01.
Article in English | MEDLINE | ID: mdl-30218728

ABSTRACT

Rheological properties of tapioca starch-galactomannan mixtures at different concentrations (0, 0.3, 0.6 and 1.0%, w/w) of guar gum, tara gum and locust bean gum were investigated in visco-analysis, steady and dynamic shear and textural analysis. Galactomannans may influence the pasting temperature and other pasting parameters, the viscosity and pseudoplasticity of the blend systems increased as time-dependence and thixotropy decreased. This can be explained by the phase separation of systems where the galactomannans were placed in the continuous phase and the volume fraction of starch granules increased its concentration in the disperse phase. The addition of guar gum and tara gum could accelerate the formation of new structures and increase the degree of structural recovery until a 50% more than the starch gel pastes. The apparent viscosity (ηa) and dynamic moduli (G' and G″) of the mixed pastes increased with the addition of galactomannans. Changes in textural properties were significant. The gel hardness, gel strength and adhesiveness of gel pastes were higher in the starch-tara gum and starch-locust bean gum systems than in the starch-guar gum system in gum concentrations values of 0.3 and 0.6% w/w. Overall, addition of galactomannans affected the rheological and textural properties of tapioca starch.


Subject(s)
Manihot/chemistry , Mannans/chemistry , Rheology , Starch/chemistry , Elasticity , Food Additives/chemistry , Galactose/analogs & derivatives , Viscosity
5.
Sensors (Basel) ; 17(8)2017 Jul 27.
Article in English | MEDLINE | ID: mdl-28749407

ABSTRACT

Multi-robot missions are a challenge for operators in terms of workload and situational awareness. These operators have to receive data from the robots, extract information, understand the situation properly, make decisions, generate the adequate commands, and send them to the robots. The consequences of excessive workload and lack of awareness can vary from inefficiencies to accidents. This work focuses on the study of future operator interfaces of multi-robot systems, taking into account relevant issues such as multimodal interactions, immersive devices, predictive capabilities and adaptive displays. Specifically, four interfaces have been designed and developed: a conventional, a predictive conventional, a virtual reality and a predictive virtual reality interface. The four interfaces have been validated by the performance of twenty-four operators that supervised eight multi-robot missions of fire surveillance and extinguishing. The results of the workload and situational awareness tests show that virtual reality improves the situational awareness without increasing the workload of operators, whereas the effects of predictive components are not significant and depend on their implementation.

6.
Biochem Biophys Res Commun ; 492(4): 659-667, 2017 10 28.
Article in English | MEDLINE | ID: mdl-28188791

ABSTRACT

While Zika virus (ZIKV) outbreaks are a growing concern for global health, a deep understanding about the virus is lacking. Here we report a contribution to the basic science on the virus- a detailed computational analysis of the non structural protein NS2b. This protein acts as a cofactor for the NS3 protease (NS3Pro) domain that is important on the viral life cycle, and is an interesting target for drug development. We found that ZIKV NS2b cofactor is highly similar to other virus within the Flavivirus genus, especially to West Nile Virus, suggesting that it is completely necessary for the protease complex activity. Furthermore, the ZIKV NS2b has an important role to the function and stability of the ZIKV NS3 protease domain even when presents a low conservation score. In addition, ZIKV NS2b is mostly rigid, which could imply a non dynamic nature in substrate recognition. Finally, by performing a computational alanine scanning mutagenesis, we found that residues Gly 52 and Asp 83 in the NS2b could be important in substrate recognition.


Subject(s)
Models, Chemical , Models, Molecular , Sequence Homology, Amino Acid , Viral Nonstructural Proteins/chemistry , Viral Nonstructural Proteins/ultrastructure , Zika Virus/enzymology , Amino Acid Sequence , Computer Simulation , Protein Conformation , Protein Domains
7.
Food Chem ; 194: 891-9, 2016 Mar 01.
Article in English | MEDLINE | ID: mdl-26471632

ABSTRACT

Starch-guar gum mixtures were obtained by extrusion using a three-variable Box-Behnken statistic design. Morphology, expansion index, viscosity, crystallinity and digestion in vitro of the extruded samples were analyzed through response surface methodology (RSM). The extrusion temperature and the moisture content were the factors that significantly affected the physicochemical properties of the samples. Starch-guar gum samples showed expansion index and viscosity up to 1.55 and 1400mPas, respectively. The crystallinity of the samples was modified by adding guar gum to the extrudates, showing correlation between long-range order (X-ray diffraction) and short-range order (FTIR spectroscopy). Guar induced microstructural changes and its role in gelatinization-melting processes was significant. The rate of glucose release decreased from 0.47 to 0.43mM/min when the extrusion temperature decreased. However, adding guar gum to starch had no significant effect on glucose release. Overall, the extrusion temperature and the moisture content were the factors that significantly affected the physicochemical properties of the extruded samples.


Subject(s)
Galactans/chemistry , Mannans/chemistry , Plant Gums/chemistry , Starch/chemistry , Water/chemistry , Chemical Phenomena
8.
Sensors (Basel) ; 15(12): 31362-91, 2015 Dec 12.
Article in English | MEDLINE | ID: mdl-26703597

ABSTRACT

Poaching is an illegal activity that remains out of control in many countries. Based on the 2014 report of the United Nations and Interpol, the illegal trade of global wildlife and natural resources amounts to nearly $ 213 billion every year, which is even helping to fund armed conflicts. Poaching activities around the world are further pushing many animal species on the brink of extinction. Unfortunately, the traditional methods to fight against poachers are not enough, hence the new demands for more efficient approaches. In this context, the use of new technologies on sensors and algorithms, as well as aerial platforms is crucial to face the high increase of poaching activities in the last few years. Our work is focused on the use of vision sensors on UAVs for the detection and tracking of animals and poachers, as well as the use of such sensors to control quadrotors during autonomous vehicle following and autonomous landing.

9.
Salud pública Méx ; 56(6): 619-624, nov.-dic. 2014. ilus, tab
Article in Spanish | LILACS | ID: lil-733340

ABSTRACT

Objetivo. Conocer la seroprevalencia y detección de infección primaria por citomegalovirus (CMV) mediante prueba de avidez de inmunoglobulina G (IgG) durante el primer trimestre del embarazo en el Hospital General de Morelia, Michoacán. Material y métodos. Se estudiaron 177 pacientes mediante prueba de Elisa modificada, la cual utiliza inmunoanálisis quimioluminiscente de micropartículas (CMIA) para detección de anti-CMV (IgG e inmunoglobulina M [IgM]) e IgG avidez. Resultados. Del total de pruebas, 90.4% resultaron positivas para IgG; de éstas, 2.3% resultaron reactivas a IgM. En este segundo grupo, la prueba de IgG avidez reportó avidez baja en 1.1% y alta en el mismo porcentaje; 9.6% fueron seronegativas. Conclusiones. Se encontró similitud con lo publicado en México. Los profesionales de la salud deben conocer los algoritmos para el diagnóstico y manejo oportuno de la infección por CMV mediante la prueba de avidez de IgG.


Objective. To determine the seroprevalence and detection of primary infection by cytomegalovirus (CMV) with immunoglobulin G (IgG) avidity test during the first quarter of pregnancy in the General Hospital in Morelia, Michoacan. Materials and methods. A total of 177 patients were studied employing a modified Elisa test using a chemiluminescent microparticle immunoassay (CMIA) for the detection of CMV antibodies (IgG and immunoglobulin M [IgM]), and IgG avidity. Results. 90.4% were positive for IgG, and of these, 2.3% were also reactive for IgM, and in this group the IgG avidity test reported low avidity for 1.1% and higher avidity in the same percentage. 9.6% were seronegative. Conclusions. Similarity was found with published studies in Mexico. Health professionals should know the clinical algorithms for diagnosis and proper management of CMV infection using the IgG avidity test.


Subject(s)
Animals , Humans , Male , Mice , Antibodies, Monoclonal/immunology , Neoplasms/enzymology , Thymidine Phosphorylase/analysis , Enzyme-Linked Immunosorbent Assay , Floxuridine/metabolism , Fluorouracil/metabolism , Mice, Inbred BALB C , Thymidine Phosphorylase/immunology , Thymidine Phosphorylase/isolation & purification
10.
Clin Chem Lab Med ; 52(9): 1305-11, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24781677

ABSTRACT

BACKGROUND: Thyroid disorders are common in women of reproductive age, and thyroid dysfunction during pregnancy has been associated with adverse outcomes for mother and child. Thyroid function and thyroid function tests (TFTs) can be influenced by a variety of factors, such as ethnicity, the presence of autoimmune thyroid disease (AITD), dietary iodine intake, pregnancy, and methodological differences. However, no large-scale studies have been published which examine TFTs and prevalence of AITD in Mexican pregnant women and women of reproductive age. METHODS: TFTs and thyroid autoantibody testing were performed on 660 pregnant and 104 non-pregnant women from Mérida, Yucatán, Mexico. After removal of thyroid autoantibody positive individuals and women with thyroid stimulating hormone (TSH) >4.94 mIU/L, reference intervals were calculated for TFT for non-pregnant women and pregnant women by trimester. RESULTS: Anti-thyroidperoxidase antibodies (TPO-Ab) and/or anti-thyroglobulin antibodies (Tg-Ab) were positive in 14.4% and 13.5% of non-pregnant and pregnant women, respectively. TSH values were significantly higher in women who were positive for TPO-Ab and co-positive for TPO-Ab and Tg-Ab. TSH values were also significantly higher in Tg-Ab positive pregnant women. Other TFTs were not significantly different based on antibody status. Using antibody negative women, reference intervals were determined for TFTs in pregnant (gestational age-specific) and non-pregnant women. CONCLUSIONS: Laboratory evidence of AITD is common in this population of Mexican pregnant and non-pregnant women. TFT results and reference intervals are influenced by pregnancy and thyroid autoimmunity. For optimal interpretation of TFT results, gestational age-specific reference intervals established using a local patient population should be used.


Subject(s)
Pregnancy Complications/diagnosis , Pregnancy/blood , Pregnancy/immunology , Thyroid Function Tests , Thyroiditis, Autoimmune/complications , Thyroiditis, Autoimmune/diagnosis , Adolescent , Adult , Autoantibodies/blood , Child , Cross-Sectional Studies , Female , Humans , Iodide Peroxidase/immunology , Mexico/epidemiology , Middle Aged , Pregnancy Complications/epidemiology , Pregnancy Complications/immunology , Prevalence , Reference Values , Thyroid Hormones/blood , Thyroiditis, Autoimmune/epidemiology , Thyrotropin/blood , Young Adult
11.
Salud Publica Mex ; 56(6): 619-24, 2014.
Article in Spanish | MEDLINE | ID: mdl-25604413

ABSTRACT

OBJECTIVE: To determine the seroprevalence and detection of primary infection by cytomegalovirus (CMV) with immunoglobulin G (IgG) avidity test during the first quarter of pregnancy in the General Hospital in Morelia, Michoacan. MATERIALS AND METHODS: A total of 177 patients were studied employing a modified Elisa test using a chemiluminescent microparticle immunoassay (CMIA) for the detection of CMV antibodies (IgG and immunoglobulin M [IgM]), and IgG avidity. RESULTS: 90.4% were positive for IgG, and of these, 2.3% were also reactive for IgM, and in this group the IgG avidity test reported low avidity for 1.1% and higher avidity in the same percentage. 9.6% were seronegative. CONCLUSIONS: Similarity was found with published studies in Mexico. Health professionals should know the clinical algorithms for diagnosis and proper management of CMV infection using the IgG avidity test.


Subject(s)
Antibodies, Viral/blood , Cytomegalovirus Infections/epidemiology , Immunoglobulin G/blood , Pregnancy Complications, Infectious/epidemiology , Adolescent , Adult , Antibody Affinity , Cross-Sectional Studies , Cytomegalovirus/immunology , Female , Hospitals, General/statistics & numerical data , Humans , Mexico/epidemiology , Middle Aged , Pregnancy , Pregnancy Trimester, First , Seroepidemiologic Studies
12.
J Biol Inorg Chem ; 12(8): 1235-49, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17786488

ABSTRACT

Nucleic acids that contain multiple sequential guanines assemble into guanine quadruplexes (G-quadruplexes). Drugs that induce or stabilize G-quadruplexes are of interest because of their potential use as therapeutics. Previously, we reported on the interaction of the Cu(2+) derivative of 5,10,15,20-tetrakis(1-methyl-4-pyridyl)-21H,23H-porphine (CuTMpyP4), with the parallel-stranded G-quadruplexes formed by d(T(4)G( n )T(4)) (n = 4 or 8) (Keating and Szalai in Biochemistry 43:15891-15900, 2004). Here we present further characterization of this system using a series of guanine-rich oligonucleotides: d(T(4)G( n )T(4)) (n = 5-10). Absorption titrations of CuTMpyP4 with all d(T(4)G( n )G(4)) quadruplexes produce approximately the same bathochromicity (8.3 +/- 2 nm) and hypochromicity (46.2-48.6%) of the porphyrin Soret band. Induced emission spectra of CuTMpyP4 with d(T(4)G( n )T(4))(4) quadruplexes indicate that the porphyrin is protected from solvent. Electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry revealed a maximum porphyrin to quadruplex stoichiometry of 2:1 for the shortest (n = 4) and longest (n = 10) quadruplexes. Electron paramagnetic resonance spectroscopy shows that bound CuTMpyP4 occupies magnetically noninteracting sites on the quadruplexes. Consistent with our previous model for d(T(4)G(4)T(4)), we propose that two CuTMpyP4 molecules are externally stacked at each end of the run of guanines in all d(T(4)G( n )T(4)) (n = 4-10) quadruplexes.


Subject(s)
Copper/chemistry , DNA/chemistry , G-Quadruplexes , Porphyrins/chemistry , Circular Dichroism , Electron Spin Resonance Spectroscopy , Models, Molecular , Oligonucleotides/chemistry , Spectrometry, Mass, Electrospray Ionization , Spectroscopy, Fourier Transform Infrared
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