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2.
Res Vet Sci ; 151: 80-89, 2022 Dec 10.
Article in English | MEDLINE | ID: mdl-35870372

ABSTRACT

Continuous Passive Motion (CPM) devices have been used to assist physicians conducting human rehabilitation; however, similar machines specific for canine rehabilitation have not been found in the reviewed literature. This research performed a physical analysis of the hind limb of dogs to design a device for implementing automated CPM exercises. The device proved to comply with the guidelines to perform CPM exercises, allowing a proper setting of parameters to generate rehabilitation routines customized for different rehabilitation requirements. Also, an electromyography acquisition module was incorporated into the system, with surface electrodes to visualize and provide feedback to the user for muscle activation. Limitations were encountered with a range of motion of 80° and an error of approximately 2% for angular position accuracy.


Subject(s)
Exercise Therapy , Motion Therapy, Continuous Passive , Animals , Dogs , Electromyography/veterinary , Exercise Therapy/veterinary , Humans , Motion Therapy, Continuous Passive/veterinary , Range of Motion, Articular/physiology
3.
Article in English | MEDLINE | ID: mdl-33998945

ABSTRACT

This research aims to provide an alternative eco-friendly way to obtain silver species and assess their bactericidal activity. This study reports the synthesis of Ag2O nanoparticles and Ag nanoparticles reduced with a green synthesis method, using a low-cost and commercial Aloe vera extract. The crystalline phases of Ag and Ag2O nanoparticles were analyzed by X-ray diffraction. The oxidation states for both species were determined by X-ray photoelectron spectroscopy. The optical properties of the material were studied through optical absorption, which resulted in well-defined band centered at 545 nm. This result is attributed to the morphology and size of the silver nanoparticles. In addition, antibacterial tests were performed on AgNPs biosynthesized with A. vera with the Kirby-Bauer protocol on Gram-negative and Gram-positive bacteria Escherichia coli and Staphylococcus aureaus, respectively. Moreover, antifungal tests were performed with various species from Candida.


Subject(s)
Aloe , Metal Nanoparticles , Anti-Bacterial Agents/pharmacology , Microbial Sensitivity Tests , Plant Extracts/pharmacology , Silver
5.
3 Biotech ; 9(4): 135, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30863714

ABSTRACT

In this work, we are proposing the green synthesis of gold nanoparticles (AuNPs) using aqueous extracts of A. triphylla and evaluating their antibacterial and catalytic properties. Characterization was performed by UV-Vis and FT-IR spectroscopies, X-ray diffraction, and transmission electron microscopy (TEM). Antibacterial activity of AuNPs was analyzed using E. coli and S. Aureus and catalytic activity was determined by the degradation of methylene blue and congo red. UV-Vis analysis showed an increase in AuNPs concentration by increasing the extract concentration, volume extract, and precursor salt concentration. The crystalline nature of AuNPs was corroborated by X-ray diffraction. TEM analysis showed nanoparticles with spherical morphology (mostly) and size between 40 and 60 nm. These results are novel because they showed a homogeneous morphology and a narrow size distribution which is difficult to obtain in green synthesis processes. Results of antibacterial activity showed inhibition zones of 11.3 mm and 10.6 mm for S. Aureus and E. coli, respectively, indicating the bactericidal capacity of the nanoparticles. The degradation periods for methylene blue and congo red were 5 and 11 min, respectively, which are very short compared with previous reports. These results are of great significance for catalytic applications. Therefore, A. triphylla extracts made possible AuNPs synthesis and the nanoparticles obtained can be used as catalytic and antibacterial materials for water remediation.

6.
Data Brief ; 20: 1220-1223, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30238030

ABSTRACT

In this document, we present the effect of the surface modification of titanium dioxide particles with dicarboxylic acid on the rheological behavior of isotactic polypropylene composites. In addition to evaluating the effect of this type of modified fillers on the crystalline parameters such as long period, crystalline thickness and amorphous thickness, comparing it with unmodified fillers and pure polymer.

7.
Mater Sci Eng C Mater Biol Appl ; 72: 42-52, 2017 Mar 01.
Article in English | MEDLINE | ID: mdl-28024605

ABSTRACT

Currently, nanomaterials had been used for several applications; one of them is as bio-markers. These nanomaterials contain fluorescent compounds as effective indicators for imaging and other applications in Biotechnology. In previous studies, we proposed a functionalized nanomaterial-based biomarker from silica and Eysenhardtia Polystachia, a medicinal tree known in Mexico as "palo azul" (Kidneywood). Our previous results showed the feasibility of the nanomaterial obtained as bio-marker. In this article, our purpose is to evaluate the effects of extraction solvents on fluorescence of that biomarker. The photoluminescence (PL) effect was evaluated at different pH (4, 7.4 and 8); four extraction solvents, ethanol, methanol, methanol-ethanol and methanol-ethanol-water were evaluated. A molecular dynamics simulation was performed to recognize molecular interaction between the compounds of the extracts with solvent molecules and to investigate the solvent molecules effect on photoluminescence spectra. The results were also compared with rhodamine 6G and we found that, at physiological pH (7.4), the fluorescent-coated silica nanoparticles obtained were also stable. We found that extraction solvents could be used for obtaining different nanomaterials for specific applications, and also found the best extraction solvent for obtaining EP nanomaterials for health care applications, specifically for imaging techniques.


Subject(s)
Biomarkers/analysis , Fabaceae/chemistry , Plant Extracts/chemistry , Solvents/chemistry , Ethanol/chemistry , Fabaceae/metabolism , Hydrogen-Ion Concentration , Methanol/chemistry , Nanoparticles/chemistry , Quantum Theory , Rhodamines/chemistry , Silicon Dioxide/chemistry , Spectrophotometry, Ultraviolet , Spectrum Analysis, Raman , Static Electricity , Water/chemistry
8.
J Nanosci Nanotechnol ; 15(12): 9473-81, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26682368

ABSTRACT

Nanometallic and bimetallic catalyst of Ni, Pt and Ni50Pt50 were studied by the decompositions of N2O. The catalyst were prepared by incipient wetness impregnation of the silica with low superficial area of 50 m2/g supported with aqueous solution of the metal precursors, for Pt H2Pt Cl6 x 6H2O was used and for Ni, Ni(NO3)2 was used to a total metal loading of 1% wt. Catalyst were oxidized for 2 hours at 400 degrees C with O2, then the samples were reduced for 30 minutes with N2 and 2 hours with H2, all at the same temperature. The catalyst was characterized by Transmission Electron Microscopy (TEM), High Angular Annular Dark Field (HAADF), High Resolution Transmission Electron Microscopy (HR-TEM) and Termoprogramed Reduction (TPR). The mean particle sizes obtained by TEM and HAADF were about 12.5 nm for Ni/SiO2, 2.8 nm for Pt/SiO2 and 3.5 nm Ni50Pt50/SiO2 catalysts respectability. HR-TEM and HAADF analysis showed differences between Ni and Pt catalysts displaying mainly cuboctahedral shapes. Stepped surface defects were found in the Ni50Pt50/SiO2 catalyst. Finally Ni50Pt50/SiO2 was more active than Pt/SiO2 and Ni/SiO2 catalysts for the decomposition of N2O.

9.
Intervirology ; 56(5): 310-5, 2013.
Article in English | MEDLINE | ID: mdl-23942143

ABSTRACT

BACKGROUND/AIMS: Human papillomavirus (HPV) is an epitheliotropic, double-stranded DNA virus, and its high-risk genotypes are associated with human cancer. HPV genome has been detected in lung carcinomas in certain places around the world, including Mexico; however, the prevalence of this is unclear. In this study, we examine the frequency of high-risk HPV 16/18 in lung cancer tissues from a Mexican population. METHODS: 39 lung cancer specimens were analyzed by polymerase chain reaction (PCR) using HPV GP5+/GP6+ primers and then were genotyped using specific primers to HPV 16/18. Additionally, in situ hybridization (ISH) was performed using BIO-labeled oligonucleotide probes. RESULTS: Our results identified 15 positive cases (38.46%) for HPV 16 and 1 positive case (2.56%) for HPV 18 by PCR. ISH showed the presence of HPV DNA in 13 of 16 (81%) samples, in agreement with the PCR results. CONCLUSIONS: In this study, we detected HPV 16/18 gene sequences in lung cancer samples obtained from Mexican patients by PCR and ISH. We found the highest prevalence of HPV 16 infection in lung adenocarcinomas, suggesting that HPV infection may be associated with lung cancer. However, further studies are needed to elucidate the role of HPV in lung carcinogenesis.


Subject(s)
Adenocarcinoma/virology , Human papillomavirus 16/isolation & purification , Human papillomavirus 18/isolation & purification , Lung Neoplasms/virology , Papillomavirus Infections/epidemiology , Papillomavirus Infections/virology , Adenocarcinoma/complications , DNA, Viral/genetics , Female , Genotype , Humans , In Situ Hybridization, Fluorescence , Lung Neoplasms/complications , Male , Mexico/epidemiology , Middle Aged , Papillomavirus Infections/complications , Polymerase Chain Reaction , Prevalence
10.
Nanoscale ; 4(7): 2281-7, 2012 Apr 07.
Article in English | MEDLINE | ID: mdl-22398420

ABSTRACT

Passivated gold nanoparticles were synthesized through a microwave-assisted process in a two-phase system, in the presence of 1-dodecanethiol. An average particle size of 1.8 nm of the gold nanoparticles obtained and 0.35 S.D. was determined through HRTEM and STEM analysis. It was observed that these nanoparticles spontaneously self-assemble into self-supported superstructures of 1 µm in diameter avg and 400 nm thickness, yielding an off-white powder which can be handled as a simple powder. XRD analysis indicates that n-alkanethiol molecules used as a passivating compound, besides protecting against crystal growth, interact to form cubic ordered arrays between the nanoparticles. This interaction leads to the superstructure formation, with an average distance between nanoparticles in the array, of 3.56 nm. Theoretical calculations and molecular dynamics simulations were performed to analyze the resulting structure.


Subject(s)
Gold/chemistry , Metal Nanoparticles/chemistry , Microwaves , Catalysis/radiation effects , Crystallization/methods , Models, Theoretical , Nanotechnology/methods , Particle Size , Polymerization/radiation effects , Sulfhydryl Compounds/chemistry , Sulfhydryl Compounds/pharmacology
11.
J Nanopart Res ; 15(1342)2012 Dec.
Article in English | MEDLINE | ID: mdl-24991190

ABSTRACT

Pt-Pd core-shell nanoparticles were synthesized using a modified polyol method. A thermal method under refluxing, carrying on the reaction up to 285 °C, has been performed to reduce metallic salts using ethylene glycol as reducer and poly(N-vinyl-2-pyrrolidone) as protective reagent of the formed bimetallic nanoparticles. According to other works, this type of structure has been studied and utilized to successfully increase the catalytic properties of monometallic nanoparticles Pt or Pd. Core-shell bimetallic nanoparticles were structurally characterized using aberration-corrected scanning transmission electron microscopy (Cs-STEM) equipped with a high-angle annular dark field detector, energy-dispersive X-ray spectrometry (EDS), and electron energy-loss spectroscopy (EELS). The high-resolution elemental line scan and mappings were carried out using a combination of STEM-EDS and STEM-EELS. The obtained results show the growth of the Pd shell on the Pt core with polyhedral morphology. The average size of the bimetallic nanoparticles was 13.5 nm and the average size of the core was 8.5 nm; consequently, the thickness of the shell was around 2.5 nm. The growth of the Pd shell on the Pt core is layer by layer, suggesting a Frank-van der Merwe growth mechanism.

12.
Nanoscale Res Lett ; 6: 553, 2011 Oct 10.
Article in English | MEDLINE | ID: mdl-21985637

ABSTRACT

In this study, Pb-filled ZnO nanowires [Pb(core)/ZnO(shell)] were synthesized by a simple and novel one-step vapor transport and condensation method by microwave-assisted decomposition of zinc ferrite. The synthesis was performed using a conventional oven at 1000 W and 5 min of treatment. After synthesis, a spongy white cotton-like material was obtained in the condensation zone of the reaction system. HRTEM analysis revealed that product consists of a Pb-(core) with (fcc) cubic structure that preferentially grows in the [111] direction and a hexagonal wurtzite ZnO-(Shell) that grows in the [001] direction. Nanowire length was more than 5 µm and a statistical analysis determined that the shell and core diameters were 21.00 ± 3.00 and 4.00 ± 1.00 nm, respectively. Experimental, structural details, and synthesis mechanism are discussed in this study.

13.
Indian J Nephrol ; 21(3): 166-71, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21886975

ABSTRACT

Podocytes are highly specialized epithelial cells that form part of the filtration barrier in the kidney, and their loss reflects a malfunction in glomerular filtration, which is usually associated with the progression of the disease. Glomerulonephritis is a serious complication that develops in about 50% of the lupus patients and is characterized by proteinuria arising from direct or indirect podocyte injury. To assess the possible role of podocytes in the pathogenesis of lupus nephritis (LN). Urinary and glomerular podocytes were detected in the kidney biopsies of patients (n = 17) with lupus nephritis, and from control biopsies obtained during autopsies. The WT-1 protein was used as a podocyte marker. The cumulative excretion of urinary podocytes was detected in the urinary sediments of LN patients and normal healthy controls, and the specimens were analyzed by immunohistochemistry, immunofluorescence, and enzyme-linked immunosorbent assay. The apoptotic index was determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling. Gross proteinuria in lupus patients was determined via 24-hour urine samples, and the results were analyzed by Student t test. Biopsy specimens from 17 patients with class-III or IV LN had lower levels of glomerular WT-1 expression than the levels found in normal kidneys (P < 0.0001). The reduction of glomerular podocytes in patients with lupus nephritis correlated with the cumulative excretion of urinary podocytes (P < 0.0001) and proteinuria. There was no correlation between the urinary podocytes and the apoptotic index in the LN urinary sediments. A decrease in glomerular podocytes is associated with their cumulative excretion in urinary sediments; therefore, such findings correlate with proteinuria in lupus nephritis patients.

14.
Reumatismo ; 63(1): 29-37, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21509347

ABSTRACT

OBJECTIVE: To assess the effect of caspase 3 inhibition, in the expression of intracellular antigens induced by apoptosis. MATERIAL AND METHODS: Skin explants of neonatal Balb/c mice were used to assess the autoantigen expression. Skin was obtained by punch biopsies, tissues were cultured in DMEM; cell death was induced by chemicals and assessed by TUNEL. The expression of La, Ro, Sm, RNP, Cajal Bodies and NuMa antigens were monitored by immunohistochemistry using autoantibodies or monoclonal antibodies against these antigens. RESULTS: Chemicals used to induce cell death, successfully produced apoptosis or necrosis in more than 60% of keratinocytes, and viability was significantly decreased when it was compared with those in controls. An increased expression of all skin intracellular antigens in skin biopsies treated with chemicals, major antigenic expression was detected with anti-La and anti-Ro antibodies. The caspase 3 inhibitor DEVD-CMK significantly decreased the expression of antigens induced by chemicals. CONCLUSION: By this result we can infer that caspase inhibitors modify apoptosis and decrease the autoantigens associated to cell death.


Subject(s)
Amino Acid Chloromethyl Ketones/pharmacology , Apoptosis/immunology , Autoantigens/biosynthesis , Autoimmune Diseases/prevention & control , Caspase Inhibitors , Cysteine Proteinase Inhibitors/therapeutic use , Skin/immunology , Animals , Animals, Newborn , Autoimmune Diseases/etiology , Biopsy , Camptothecin/pharmacology , Cells, Cultured/drug effects , Cells, Cultured/enzymology , Cells, Cultured/immunology , Cycloheximide/pharmacology , Cysteine Proteinase Inhibitors/pharmacology , Drug Evaluation, Preclinical , Hydrogen Peroxide/pharmacology , In Situ Nick-End Labeling , Mercuric Chloride/pharmacology , Mice , Mice, Inbred BALB C , Organ Culture Techniques , Skin/enzymology
15.
Carbohydr Res ; 346(1): 121-6, 2011 Jan 03.
Article in English | MEDLINE | ID: mdl-21092941

ABSTRACT

Casiopeínas are a new generation of anticancer drugs that have shown great in vitro and in vivo antineoplastic activities. Information about interaction drug-excipient, for developing a based-nanoparticle drug delivery system, has not been investigated yet. In order to elucidate if chitosan (CS) modifies the copper complex due to its interaction with Cu(2+) ion, different studies in aqueous media between CS and Casiopeina III-ia (Cas III-ia) were carried out. CS-Cas III-ia mixtures were characterized by viscosity curves, UV-vis, EPR, and in vivo activity against HeLa cell line. Rheological behavior showed a decrease of viscosity when the drug was present due to diminished electrostatic interactions of charged amine group. UV-vis results illustrate that Cas III-ia is not stable at low pH as a result of interaction with acetic acid. However, when chitosan is present at the acidic solution Cas III-ia is stable. These results are supported by EPR studies. Finally, activity of the drug against HeLa cell line was not modified. Therefore, the present work presents evidence that there is no breaking of copper complex due to interaction between CS and Cas III-ia in acidic media. In addition, Cas III-ia maintains both its stability and effectiveness against cancer cell line.


Subject(s)
Chitosan/chemistry , Organometallic Compounds/chemistry , Drug Delivery Systems , Electron Spin Resonance Spectroscopy , Thermodynamics
16.
Reumatismo ; 61(3): 212-5, 2009.
Article in English | MEDLINE | ID: mdl-19888506

ABSTRACT

Ocular rheumatoid disease manifests as hyperemia of the conjunctiva and episclera, and in severe cases, episcleritis can result in nodular sclerotic and scleromalacia perforans. A clinical case of scleromalacia perforans in a 56-year-old woman with 20 years of seropositive rheumatoid arthritis of functional class IV is presented here. During that period, she received exclusively non-steroidal anti-inflammatory drugs (NSAIDs). She developed acute episcleritis of the left ocular globe, which rapidly progressed to scleromalacia perforans. Since the left eye became perforated, it was surgically enucleated, and the patient was maintained with steroidal therapy. Nevertheless, two months later she developed new-onset episcleritis of the right eye followed by scleromalacia. She was first evaluated by a rheumatologist and treated with 200 mg/dose of infliximab, which was administered monthly for the following four months. The biological treatment was accompanied by methotrexate and prednisone. With this therapy, the ocular lesion dramatically improved, and complete remission of rheumatoid arthritis and scleritis was archived four months later. In conclusion, tumour necrosis factor (TNF) blockers are effective therapeutic agents in ocular complications of rheumatoid arthritis.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/drug therapy , Scleritis/drug therapy , Arthritis, Rheumatoid/complications , Arthritis, Rheumatoid/pathology , Drug Therapy, Combination , Female , Glucocorticoids/therapeutic use , Humans , Infliximab , Methotrexate/therapeutic use , Middle Aged , Scleritis/etiology , Scleritis/pathology , Treatment Outcome
17.
J Eur Acad Dermatol Venereol ; 23(6): 697-701, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19470049

ABSTRACT

BACKGROUND: Pemphigus is an autoimmune disease characterized by the formation of intra-epidermal blisters. Patients develop auto-antibodies against desmoglein 1 and 3 proteins and induce acantholysis. OBJECTIVE: This work addresses the issue of whether the Fas pathway mediates acantholysis. Furthermore, the possible suppliers of the Fas pathway were investigated. METHODS: Seventeen biopsies of pemphigus patients were studied by haematoxylin and eosin staining, and apoptosis was defined by TUNEL. The expression of Fas, FasL and caspase 3 was studied by in situ hybridization and immunohistochemistry. Cell infiltrates were studied by immunofluorescence with monoclonal anti-CD3, CD4, CD8, CD19 and CD69. RESULTS: All of the biopsies showed intra-epidermal blisters, acantholytic cells and inflammatory infiltrates. The blisters expressed Fas, FasL and caspase 3. Cell infiltrates were composed of CD8 and a few CD4(+)CD69(+) cells. Additionally, CD19(+) cells were detected. Interestingly, the Fas expression was increased in acantholytic cells and perilesional keratinocytes. Incidentally, these cells exhibited apoptotic features. Interestingly, the CD8 cells expressed FasL. CONCLUSION: This paper presents the morphological evidence that apoptosis and acantholysis are linked. Therefore, the Fas pathway is associated with CD8 cells in pemphigus lesions.


Subject(s)
Acantholysis/pathology , Pemphigus/pathology , fas Receptor/physiology , Adult , Base Sequence , Biopsy , DNA Primers , Female , Fluorescent Antibody Technique , Humans , In Situ Hybridization , In Situ Nick-End Labeling , Male , Polymerase Chain Reaction
18.
Inflamm Res ; 58(2): 61-6, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19184355

ABSTRACT

OBJECTIVE: Examine the presence of functional inducible nitric oxide synthase (iNOS) in lupus nephritis lesions. METHODS: Seventeen kidney biopsies from patients with lupus nephritis and an equal number of normal control kidney biopsies were examined for the presence of iNOS and endothelial nitric oxide synthase (eNOS) and citrulline by using immunohistochemical methods. Additionally, iNOS and eNOS mRNAs were examined by reverse transcription -PCR amplification of total renal RNA. RESULTS: All biopsies expressed constitutive eNOS, but in contrast to normal kidney biopsies, 70% of the lupus biopsies also expressed iNOS mRNA and the cognate protein. Eight positive biopsies corresponded to class IV lupus nephritis, which also had a high degree of citrullination. CONCLUSIONS: The data indicate that functional iNOS activity is present in glomeruli as part of the inflammatory process in the kidney; therefore the products of iNOS could play a role in the pathogenesis of lupus nephritis.


Subject(s)
Citrulline/metabolism , Kidney , Lupus Nephritis/metabolism , Lupus Nephritis/pathology , Nitric Oxide Synthase Type II/metabolism , Adolescent , Adult , Animals , Biopsy , Female , Humans , Kidney/metabolism , Kidney/pathology , Lupus Nephritis/classification , Male , Mice , Mice, Inbred BALB C , Nitric Oxide , Nitric Oxide Synthase Type III/metabolism , Young Adult
19.
Microsc Microanal ; 15(1): 46-53, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19144257

ABSTRACT

ZrO2:Yb3+ nanocrystalline phosphors with high concentrations of ytterbium ions were prepared using the sol-gel method. X-ray diffraction, high-angle annular-dark-field scanning transmission electron microscopy (HAADF-STEM), energy dispersive X-ray spectroscopy, and high-resolution transmission electron microscopy (HRTEM) were used to characterize the nanocrystalline phosphors annealed at 1000 degrees C. Unit-cell distortion and changes in the crystalline structure of the monoclinic zirconia to tetragonal zirconia, and subsequently cubic zirconia, were observed with increased Yb concentration. Yb ions were randomly distributed into the lattice of the crystalline structure. No segregation of Yb2O3 phase was observed. The substitution of Zr atoms by Yb atoms on different crystalline phases was confirmed by the experimental results and theoretical simulations of HRTEM and HAADF-STEM.

20.
J Colloid Interface Sci ; 331(1): 185-90, 2009 Mar 01.
Article in English | MEDLINE | ID: mdl-19038394

ABSTRACT

We study the confinement of a hydrophilic polymer (polyethylene glycol or PEG) between the bilayers of the zwitterionic surfactant tetradecyldimethyl aminoxide (C(14)DMAO). Small angle X-ray scattering and electron microscopy experiments show that the polymer modifies the physical properties of the lyotropic smectic (L(alpha)) phase. The observed effects are similar to those reported for anchored hydrophobically-modified polymers, indicating a strong interaction between PEG and the C(14)DMAO bilayers. Self-diffusion experiments performed in the lyotropic sponge (L(3)) phase show that the polymer adsorbs onto the surfactant membranes. This adsorption explains earlier observations: high polymer concentrations decrease the Gaussian rigidity of the membranes and a vesicular phase is stabilized.

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