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Background: Assisted reproduction techniques in birds have contributed to many species' conservation and sustainable use. One of these techniques is semen cryopreservation, which is possible following the discovery of suitable cryoprotectants. Aims: This study aimed to characterize the fresh and post-thaw ejaculates of different species of birds of prey. Methods: The following species were included in the study: red-tailed hawk (Buteo jamaicensis) n=3, golden eagle (Aquila chrysaetos) n=3, and Harris's hawk (Parabuteo unicinctus) n=3. Twenty-five ejaculates were obtained for each species. The percentage of spermatozoa motility, viability, and morphology were evaluated. Results: Evident differences were observed among the ejaculates of the three species, particularly in sperm length and between the fresh and post-thaw parameters of the same species in which the motility reduced to approximately 40% after thawing. It was demonstrated that sperm cryopreservation of the studied species was possible using the same freezing protocol. Conclusion: This study showed that sperm characteristics could influence the parameters obtained during their in vitro conservation, both in the fresh and post-thaw states.
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The synthesis method and correlation between compositional, vibrational, and electrical properties in graphene oxide fibers (GOF) are presented and discussed here, as well as a potential application through the development of a heater device based on GOF. The GOF samples were synthesized from rice husk (RH), via a thermal decomposition method, employing an automated pyrolysis system with a controlled nitrogen atmosphere, varying carbonization temperature (TCA) from 773 to 1273 K. The compositional analysis shows peaks in the XPS spectrum associated with C1s and O1s, with presence of hydroxyl and epoxy bridges; the oxide concentration (OC) of samples varied from 0.21 to 0.28, influenced by TCA. The GOF samples exhibit fiber morphology, vibrational characteristics which are typical of graphene oxide multilayers, and electrical behavior that scales with OC. The electrical response shows that OC decreases and increases electrical conductivity at the polycrystalline phase, possibly attributed to the desorption of some oxides and organic compounds. In addition, physical correlations between OC and its vibrational response showed that decreasing OC increases edge defect density and decreases crystal size as a result of thermal decomposition processes. The correlation between OC and physical properties suggests that by controlling the OC in GOF, it was possible to modify vibrational and electrical properties of great interest in fabrication of advanced electronics; consequently, we show a potential application of GOF samples by developing an electrically controlled heater device.
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In the last decade, the highest levels of greenhouse gases (GHG) in the atmosphere have been recorded, with carbon dioxide (CO2) being one of the GHGs that most concerns mankind due to the rate at which it is generated on the planet. Given its long time of permanence in the atmosphere (between 100 to 150 years); this has deployed research in the scientific field focused on the absorption and desorption of CO2 in the atmosphere. This work presents the study of CO2 adsorption employing materials based on graphene oxide (GO), such as GO foams with different oxidation percentages (3.00%, 5.25%, and 9.00%) in their structure, obtained via an environmentally friendly method. The characterization of CO2 adsorption was carried out in a closed system, within which were placed the GO foams and other CO2 adsorbent materials (zeolite and silica gel). Through a controlled chemical reaction, production of CO2 was conducted to obtain CO2 concentration curves inside the system and calculate from these the efficiency, obtained between 86.28 and 92.20%, yield between 60.10 and 99.50%, and effectiveness of CO2 adsorption of the materials under study. The results obtained suggest that GO foams are a promising material for carbon capture and the future development of a new clean technology, given their highest CO2 adsorption efficiency and yield.
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RESUMEN La anestesia aviar constituye un área de estudio controvertida debido a la morfofisiología diferente entre aves y mamíferos. Lo anterior hace necesario desarrollar protocolos confiables que contribuyan al bienestar de las aves en cautiverio. La anestesiología en aves representa una actividad clínica que demanda especial cuidado de los pacientes que requieren procedimientos quirúrgicos. Este estudio describe los parámetros de SpO2, frecuencias cardiaca y respiratoria durante la anestesia con isoflurano de Melopsittacus undulatus. Se monitorearon 12 machos y 7 hembras durante las etapas anestésicas. La inducción anestésica duró 1:30 ± 0:31 min en machos y 2:19 ± 0:16 min en hembras, con promedio de mantenimiento de 7:00 ± 1:39 min. No se encontraron diferencias significativas en los tiempos anestésicos entre hembras y machos (p>0,05). Se presentó una variación estadísticamente significativa (p<0,05) de la SpO2 en el periodo de recuperación, las hembras presentaron mayor saturación de oxígeno (71±4 %) en comparación con los machos (89±2 %). En la valoración de la función cardiaca durante la anestesia, no se detectaron diferencias significativas entre machos y hembras (p>0,05). Se concluye como un protocolo anestésico seguro para procedimientos clínicos de corta duración para aves pequeñas como M. undulatus.
ABSTRACT Avian anesthesia is a controversial area of study due to the differences between birds and mammals morpho physiology. This makes necessary to develop reliable protocols for birds in captivity, which contributes to their welfare under human care. Bird anesthesiology today represents a veterinary clinical activity that demands special care for patients requiring surgical procedures. This study describes the parameters of SpO2, cardiac activity, heart and respiratory rate during anesthesia with isoflurane for Melopsittacus undulatus. 12 males and 7 females were monitored during the anesthetic stages. Anesthetic induction lasted 1:30 ± 0:31 min in males and 2:19 ± 0:16 min in females, with an average maintenance time of 7:00 ± 1:39 min. No significant differences were found in anesthetic times between females and males (p>0.05). There was a statistically significant variation (p<0.05) of SpO2 in the recovery period, females had higher oxygen saturation (71±4%) compared to males (89±2%). In the assessment of cardiac function during anesthesia, no significant differences were detected between males and females (p>0.05). It is concluded as a safe anesthetic protocol for clinical procedures of short duration for small birds such as M. undulates.
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The rapid development of optoelectronic applications for optical-to-electrical conversion has increased the interest in graphene oxide material. Here, graphene oxide films (GOF) were used as source material in an infrared photodetector configuration and the temperature dependence of the electrical conductivity was studied. GOF were prepared by the double-thermal decomposition (DTD) method at 973 K, with a fixed carbonization temperature, in a pyrolysis system, under a controlled nitrogen atmosphere, over quartz substrates. Graphene oxide films were mechanically supported in a photodetector configuration on Bakelite substrates and electrically contacted with copper wires and high-purity silver paint. Morphological images from the GOF's surface were taken employing a scanning electron microscope and observed a homogeneous surface which favored the electrical contacts deposition. Vibrational characteristics were studied employing Raman spectroscopy and determined the typical graphene oxide bands. GOF were used to discuss the effect of temperature on the film's electrical conductivity. Current-voltage (I-V) curves were taken for several temperatures varying from 20 to 300 K and the electrical resistance values were obtained from 142.86 to 2.14 kΩ. The GOF electrical conductivity and bandgap energy (Eg) were calculated, and it was found that when increasing temperature, the electrical conductivity increased from 30.33 to 2023.97 S/m, similar to a semiconductor material, and Eg shows a nonlinear change from 0.33 to 0.12 eV, with the increasing temperature. Conduction mechanism was described mainly by three-dimensional variable range hopping (3D VRH). Additionally, measurements of voltage and electrical resistance, as a function of wavelength were considered, for a spectral range between 1300 and 3000 nm. It was evidenced that as the wavelength becomes longer, a greater number of free electrons are generated, which contributes to the electrical current. The external quantum efficiency (EQE) was determined for this proposed photodetector prototype, obtaining a value of 40%, similar to those reported for commercial semiconductor photodetectors. This study provides a groundwork for further development of graphene oxide films with high conductivity in large-scale preparation.
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BACKGROUND: Cardiovascular disease accounts for 35% to 50% of the causes of mortality in chronic kidney disease. The majority of patients in substitution therapy in Mexico are subdialyzed owing to limited economic resources. This produces more cardiac deterioration than described in the statistics and has a direct impact on the prognosis of kidney transplantation. The aim of this work was to demonstrate and to quantify the improvement in the echocardiographic parameters 6 months after renal transplantation in patients with stable renal function. METHODS: This was an observational, analytic, prospective study of 23 patients with chronic kidney disease who received transplants in 2016 and had a glomerular filtration rate ≥80 mL/min (Chronic Kidney Disease-Epidemiology Collaboration) 6 months after transplantation. RESULTS: Echocardiographic results showed an increase in the left ventricular ejection fraction from 57.17 ± 10.46% to 64.09 ± 9.8%, an increase in the right ventricular ejection fraction from 0.56 ± 0.09% to 0.60 ± 0.08% and a reduction of the pulmonary arterial systolic pressure from 44.57 ± 13.88 mm Hg to 39.74 ± 11.04 mm Hg. There were also decreases in mitral regurgitation from 1.0 to 0.43, tricuspid insufficiency from 1.35 to 0.43, pulmonary insufficiency from 0.48 to 0.04, and aortic insufficiency from 0.35 to 0.04, all of these significant with P < .05. CONCLUSIONS: There was a significant improvement in cardiovascular function in our population 6 months after transplantation, despite the fact that renal transplantation is performed with greater cardiac deterioration than described in patients in other countries.
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Cardiopatias/etiologia , Cardiopatias/fisiopatologia , Transplante de Rim , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/cirurgia , Idoso , Ecocardiografia , Feminino , Humanos , Masculino , México , Pessoa de Meia-Idade , Prognóstico , Estudos ProspectivosRESUMO
INTRODUCTION: The appearance of patellofemoral pain after a knee arthroplasty, particularly in rheumatic diseases, resulted in the incorporation of the substitution of the patellar component in all designs. The replacement of the patella became a standard part of knee arthroplasty, but the controversy over whether to restore it or not continues among orthopedists that perform knee arthroplasties. OBJECTIVE: To analyze the incidence of anterior knee pain in patients who underwent primary knee arthroplasty with or without replacement of the patellar component. MATERIAL AND METHODS: Observational, retrospective, descriptive and transversal study from January 2011 to December 2013. RESULTS: A total of 54 patients were included, 12 men (with an average age of 63 years) and 42 women (with an average age of 71 years), totaling 64 knees that were surgically intervened. CONCLUSION: This study found no significant difference in anterior knee pain and in the function of the patellofemoral joint and the knee in the groups of patients who were tested with the different scales.
La aparición de dolor patelofemoral postoperatorio en la artroplastía de rodilla, sobre todo en pacientes reumáticos, resultó en la incorporación de la sustitución del componente patelar en la mayoría de los diseños. Esta se convirtió en una parte estándar de la artroplastía total de rodilla; la controversia sobre si restituir o no el componente patelar continúa siendo debatida por los cirujanos ortopedistas que realizan artroplastías de rodilla.
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Artroplastia do Joelho , Dor , Patela , Idoso , Artroplastia do Joelho/efeitos adversos , Feminino , Humanos , Articulação do Joelho , Masculino , Osteoartrite do Joelho , Dor/etiologia , Patela/patologia , Estudos Retrospectivos , Resultado do TratamentoRESUMO
The large-scale production of graphene and reduced-graphene oxide (rGO) requires low-cost and eco-friendly synthesis methods. We employed a new, simple, cost-effective pyrolytic method to synthetize oxidized-graphenic nanoplatelets (OGNP) using bamboo pyroligneous acid (BPA) as a source. Thorough analyses via high-resolution transmission electron microscopy and electron energy-loss spectroscopy provides a complete structural and chemical description at the local scale of these samples. In particular, we found that at the highest carbonization temperature the OGNP-BPA are mainly in a sp(2) bonding configuration (sp(2) fraction of 87%). To determine the electrical properties of single nanoplatelets, these were contacted by Pt nanowires deposited through focused-ion-beam-induced deposition techniques. Increased conductivity by two orders of magnitude is observed as oxygen content decreases from 17% to 5%, reaching a value of 2.3 × 10(3) S m(-1) at the lowest oxygen content. Temperature-dependent conductivity reveals a semiconductor transport behavior, described by the Mott three-dimensional variable range hopping mechanism. From the localization length, we estimate a band-gap value of 0.22(2) eV for an oxygen content of 5%. This investigation demonstrates the great potential of the OGNP-BPA for technological applications, given that their structural and electrical behavior is similar to the highly reduced rGO sheets obtained by more sophisticated conventional synthesis methods.
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Condutividade Elétrica , Grafite , Oxirredução , Óxidos , OxigênioRESUMO
Al plantear que los seres vivos utilizan la energía que disipan para generar su propia estructura, el Principio de Margalef relaciona la capacidad metabólica con la generación de masa corporal. El estudio de la Tasa Metabólica Basal (TMB) y el peso corporal, pueden ayudar a observar la relación propuesta. La capacidad de disipar energía contribuye a generar una creciente estructura, a la vez que declina con el tiempo. En ese marco, la precisión del concepto de peso metabólicamente activo es fundamental. La dinámica de la relación entre estas dos variables, puede colaborar en la comprensión de ciertos aspectos fundamentales de los seres vivos. Y la adecuada definición del peso metabólicamente activo puede influir sobre aspectos clínicos de esta relación.
In arguing that living things use their dissipated energy to generate their own structure, the Margalef principle relates metabolic capacity to body mass. By studying the Basal Metabolic Rate (BMR) and body weight we can observe the proposed relationship. The ability to dissipate energy contributes to a growing structure and declines over time. In this context, the accuracy of the concept of metabolically active weight is fundamental. The dynamics of the relationship between these two variables may contribute to an understanding of fundamental aspects of living organisms. In addition, a proper definition of the metabolically active weight may influence the clinical aspects of this relationships.
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To support a risk assessment of manganese exposure in two communities living within a manganese mining district a cross-sectional study was performed on a sample of the adult population of long-term residents. One community was exposed to a point source from an ore primary refining plant. Manganese is an essential mineral for human life. It is also the fourth in importance for industrial metal making. Data were collected on socioeconomic living conditions, emission sources, environmental media concentrations (air, water, soil, dust, food), respiratory symptomatology, and a neuropsychological examination (Mini-Mental Screening test, the Hooper Visual Organization test, the Ardila-Ostroski, and others). We examined 73 subjects (52 women), most of low socioeconomic status. Environmental air concentrations were 2 to 3 times higher than those in other urban concentrations. Manganese blood concentrations ranged from 7.5 to 88 microg/L, with a median concentration of 15, the upper quartile starting at 20 microg/L; the upper 10% was above 25 microg/L. Lead and manganese were highly correlated; there was an inverse relation to hemoglobin. Reduced levels of plasma lipid peroxidation were associated with blood manganese. Using multivariate logistic regression, we identified B-Mn as increasing the risk of deficient cognitive performance 12 times (Mini-Mental score of less than 17).
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Transtornos Cognitivos/induzido quimicamente , Exposição Ambiental , Manganês/efeitos adversos , Saúde Pública , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Indústrias , Chumbo/efeitos adversos , Chumbo/sangue , Peroxidação de Lipídeos , Masculino , Manganês/sangue , México , Pessoa de Meia-Idade , Projetos Piloto , Medição de Risco , Classe Social , População UrbanaRESUMO
Female CBi mice subjected to multiple exposures to halothane inhalation anesthesia before mating were investigated for the potential effects of such intervention on a specific antibody response mounted by them and their offspring. An assessment of the toxicologic and reproductive performance of female mice undergoing anesthesia was also performed. Adult female mice received three episodes of halothane anesthesia at weekly intervals. Seventy-two hours after the last dose, mice were subjected to the following procedures: 1) study of the specific humoral immune response to sheep red blood cells (SRBC); 2) hematologic, hepatologic, and histopathologic studies; and 3) mating with syngeneic sires. Halothane-treated females had increased amounts of specific antibody secreting B cells, with liver studies showing evidence of microscopic fatty changes and decreased lipid peroxidation. Anesthesia did not alter reproductive performance but lowered offspring survival. Offspring displayed depressed antibody response after challenge with SRBC at weaning and at 60 d of age. The anti-SRBC antibody response that was found to be enhanced in halothane anesthetized females, seemed to be conversely impaired when studied in the offspring.
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Anestésicos Inalatórios/toxicidade , Halotano/toxicidade , Sistema Imunitário/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Animais , Formação de Anticorpos/efeitos dos fármacos , Células Produtoras de Anticorpos/efeitos dos fármacos , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Contagem de Células Sanguíneas/efeitos dos fármacos , Eritrócitos/imunologia , Feminino , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos , Tamanho do Órgão/efeitos dos fármacos , Gravidez , Baço/imunologia , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismoRESUMO
The extent of surgery, the patient's age, health status and other factors may contribute to alteration of the immune system during anesthesia and surgery. In addition, inhalatory anesthetics may cause acute and chronic toxicity because of the production of intermediate and end metabolic compounds. The present work was undertaken to evaluate, both in vivo and in vitro, if repeated doses of halothane were able to affect the immune response in a murine model developed at our laboratory. Weekly doses of halothane were administered to mice subjected to no surgery and three days after the last anesthetic-exposure, several immunologic parameters were assessed. Results on the in vivo response to sheep red blood cells showed that halothane treatment increased the amount of specific antibody secreting B-cells, without affecting the delayed type hypersensitivity reaction to the same antigen. In vitro studies on spleen cell composition showed that halothane re-exposure diminished the number of CD4+, CD8+ and B-cells. Such changes were not translated into alterations on the mitogen-driven lymphoproliferation, as well as macrophage phagocytic and lytic functions. Our results indicate that halothane re-exposure is able to modulate the immune response affecting both the number of antibody secreting cells involved in a specific in vivo response, and the splenic lymphoid cell composition. Since such halothane-induced immune alterations might bias the results of a wide range of physiological research, even those involving other systems, a careful selection of the anesthetic agent and methods by which the compound is administered is advisable.
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Anestésicos Inalatórios/farmacologia , Halotano/farmacologia , Baço/efeitos dos fármacos , Animais , Subpopulações de Linfócitos/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos , Fagocitose/efeitos dos fármacos , Baço/imunologiaRESUMO
The impact that reexposure to anesthetics delivered in 100% oxygen or in synthetic air (21% oxygen/79% nitrogen) has on the secondary humoral immune response to sheep red blood cells was studied. Mice were immunized twice with a 15-day interval and anesthetized immediately after each antigenic challenge with 1.5% halothane or 1.5% isoflurane for 40 min. Halothane in oxygen resulted in increased numbers of IgG-secreting cells (IgG-SC), while halothane in air depressed the response when compared to control mice. In contrast, isoflurane vaporized in oxygen did not affect IgG-SC numbers, while isoflurane given in air lowered the response. Furthermore, neither 100% oxygen, nor the stress of being in an anesthesia chamber breathing synthetic air for 40 min had any immunological effect in non-anesthetized mice. The inspired oxygen concentration during halothane or isoflurane anesthesia has an effect on the secondary immune response. The effect is different between halothane and isoflurane, possibly due to differences in the extent of their metabolic and pharmacodynamic properties.
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Anestésicos Inalatórios/farmacologia , Formação de Anticorpos/efeitos dos fármacos , Halotano/farmacologia , Memória Imunológica/efeitos dos fármacos , Isoflurano/farmacologia , Animais , Células Produtoras de Anticorpos , Contagem de Células , Eritrócitos/imunologia , Imunoglobulina G/biossíntese , Masculino , Camundongos , Camundongos Endogâmicos , Ovinos , Baço/citologiaRESUMO
There were analyzed in a retrospective way the results of pre-retrieval hormonal levels as well as the number of retrieved oocytes, mature oocytes and transferred embryos in three groups of patients (2 GIFT, 1 IVF-ET) which achieved a pregnancy, and were matched with groups with no pregnancy. There were no statistically significant differences in most of the analyzed parameters, by the aforementioned we can suppose that pregnancy depends of endometrial quality and in this moment we are not able to modify it satisfactorily.
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Transferência Embrionária , Fertilização in vitro , Transferência Intrafalopiana de Gameta , Adulto , Estrogênios/sangue , Feminino , Humanos , GravidezRESUMO
The effect of halothane anesthesia on the humoral immune response to sheep red blood cells was studied in mice immunized twice, with a 15-day interval. On both occasions, mice were exposed to 1.5% halothane for 40 min immediately after sensitization. Halothane reexposure resulted in increased numbers of IgG-secreting cells (IgG-SC) as well as circulating 7S-serum agglutinins. To examine further whether this effect could be obtained in syngeneic recipients, adoptive transfer experiments employing spleen cells were performed. While mice receiving cells from unimmunized and anesthetized donors displayed significantly higher levels of IgG-SC, recipients of cells from normal, immunized and immunized-anesthetized donors showed a depressed response when compared to control counterparts. Besides the possibility of an enhancing effect of halothane reexposure on the humoral response, this procedure may counteract normal physiological immunoregulatory processes during the generation of the immune response.