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1.
Proc Natl Acad Sci U S A ; 117(42): 26263-26272, 2020 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-33020307

RESUMEN

Closed-canopy rainforests are important for climate (influencing atmospheric circulation, albedo, carbon storage, etc.) and ecology (harboring the highest biodiversity of continental regions). Of all rainforests, Amazonia is the world's most diverse, including the highest mammalian species richness. However, little is known about niche structure, ecological roles, and food resource partitioning of Amazonian mammalian communities over time. Through analyses of δ13Cbioapatite, δ13Chair, and δ15Nhair, we isotopically characterized aspects of feeding ecology in a modern western Amazonian mammalian community in Peru, serving as a baseline for understanding the evolution of Neotropical rainforest ecosystems. By comparing these results with data from equatorial Africa, we evaluated the potential influences of distinct phylogenetic and biogeographic histories on the isotopic niches occupied by mammals in analogous tropical ecosystems. Our results indicate that, despite their geographical and taxonomic differences, median δ13Cdiet values from closed-canopy rainforests in Amazonia (-27.4‰) and equatorial Africa (-26.9‰) are not significantly different, and that the median δ13Cdiet expected for mammalian herbivores in any closed-canopy rainforest is -27.2‰. Amazonian mammals seem to exploit a narrower spectrum of dietary resources than equatorial African mammals, however, as depicted by the absence of highly negative δ13Cdiet values previously proposed as indicative of rainforests (<-31‰). Finally, results of keratin and bioapatite δ13C indicate that the predictive power of trophic relationships, and traditional dietary ecological classifications in bioapatite-protein isotopic offset expectations, must be reconsidered.


Asunto(s)
Isótopos de Carbono/análisis , Ecología/métodos , Fósiles/diagnóstico por imagen , África , Animales , Biodiversidad , Isótopos de Carbono/metabolismo , Dieta , Ecosistema , Mamíferos , Isótopos de Nitrógeno/análisis , Perú , Filogenia , Bosque Lluvioso
2.
Pain Med ; 21(11): 3018-3023, 2020 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-32150272

RESUMEN

OBJECTIVE: Vertebroplasty is a percutaneous minimally invasive procedure indicated for vertebral collapse pain treatment. Among the known complications of the procedure is the augmented risk of new vertebral fractures. There are no specific studies in this patient population describing the risk of new vertebral fractures after vertebroplasty. This study analyzed risk factors associated with new vertebral fractures after vertebroplasty in patients with multiple myeloma. METHODS: Observational retrospective study in patients with multiple myeloma. The data collection took place from January 1, 2010, to December 30, 2017, at the National Cancer Institute. Clinical data and procedural variables such as cement volume, cement leaks, fracture level, number of treated vertebrae, pedicular disease, and cement distribution pattern, with two years follow-up, were analyzed with the Wilcoxon test, and a logistic regression model was used to identify risk factors related to new vertebral fractures. A confidence interval of 95% was used for analysis. RESULTS: At one-year follow-up, 30% of fractures were reported after vertebroplasty, most of them at low thoracic and lumbar level (50% adjacent level). Vertebroplasty was most commonly performed at the thoracolumbar and lumbar area. We demonstrated a 70.7% median numerical rating scale reduction at one-year follow-up; a significant decrease in opioid consumption occurred only during the first month. CONCLUSIONS: Pedicle involvement, disc leakage, cement volume, thoracolumbar and lumbar level, and number of treated vertebrae by intervention are important risk factors when performing vertebroplasty. Prospective randomized studies are needed to evaluate these factors in this specific population.


Asunto(s)
Fracturas por Compresión , Mieloma Múltiple , Osteoporosis , Vertebroplastia , Cementos para Huesos/efectos adversos , Fracturas por Compresión/epidemiología , Fracturas por Compresión/etiología , Fracturas por Compresión/cirugía , Humanos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Mieloma Múltiple/epidemiología , Estudios Prospectivos , Estudios Retrospectivos , Vértebras Torácicas/cirugía , Resultado del Tratamiento , Vertebroplastia/efectos adversos
3.
Inorg Chem ; 58(1): 811-820, 2019 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-30525533

RESUMEN

The multicomponent alloy HfNbTiVZr has been described as a single-phase high-entropy alloy (HEA) in the literature, although some authors have reported that additional phases can form during annealing. The thermal stability of this alloy has therefore been investigated with a combination of experimental annealing studies and thermodynamic calculations using the CALPHAD approach. The thermodynamic calculations show that a single-phase HEA is stable above about 830 °C. At lower temperatures, the most stable state is a phase mixture of bcc, hcp, and a cubic C15 Laves phase. Annealing experiments followed by quenching confirm the results from thermodynamic calculations with the exception of the Laves phase structure, which was identified as a hexagonal C14 type instead of the cubic C15 type. Limitations of the applied CALPHAD thermodynamic description of the system could be an explanation for this discrepancy. As-synthesized HfNbTiVZr alloys prepared by arc-melting form a single-phase bcc HEA at room temperature. In situ annealing studies of this alloy show that additional phases start to form above 600 °C. This indicates that the observed HEA is metastable at room temperature and stabilized by a slow kinetics during cooling. X-ray diffraction analyses using different cooling rates and annealing times show that the phase transformations in this HEA are slow and that completely different phase compositions can be obtained depending on the annealing procedure. In addition, it has been shown that the sample preparation method (mortar grinding, heat treatment, etc.) has a significant influence on the collected diffraction patterns and therefore on the phase identification and analysis.

4.
Gac Med Mex ; 155(3): 307-318, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31219471

RESUMEN

The interest on cannabinoids became evident between the 1940 and 1950 decades. Although the active substance of the plant was not known, a series of compounds with cannabinomimetic activity were synthesized, which were investigated in animals and clinically. The most widely tested was Δ6a, 10a-THC hexyl. Δ6a, 10a-THC dimethylheptyl (DMHP) antiepileptic effects were studied in several children, with positive results being obtained in some cases. DMHP differs from sinhexyl in that its side chain is DMHP instead of n-hexyl. The first cannabinoid isolated from Cannabis sativa was cannabinol, although its structure was correctly characterized several years later. Cannabidiol was isolated some years later and was subsequently characterized by Mechoulam and Shvo. In 2013, the National Academy of Medicine and the Faculty of Medicine of the National Autonomous University of Mexico, through the Seminar of Studies on Entirety, decided to carry out a systematic review on a subject that is both complex and controversial: the relationship between marijuana and health. In recent years, studies have been conducted with cannabis in several diseases: controlled clinical trials on spasticity in multiple sclerosis and spinal cord injury, chronic, essentially neuropathic, pain, movement disorders (Gilles de Latourette, dystonia, levodopa dyskinesia), asthma and glaucoma, as well as non-controlled clinical trials on Alzheimer's disease, neuroprotection, intractable hiccups, epilepsy, alcohol and opioid dependence and inflammatory processes.


El interés por los cannabinoides se hizo evidente entre las décadas de 1940 y 1950. Aunque no se conocía el principio activo de la planta, se sintetizaron compuestos con actividad cannabinomimética, los cuales fueron investigados en animales y en la clínica. El más probado fue el ∆6a,10a-THC hexilo. Las acciones antiepilépticas del ∆6a,10a-THC dimetilheptil fueron estudiadas en varios niños; en algunos casos se obtuvieron resultados positivos. El ∆6a,10a-THC dimetilheptil se diferencia del sinhexil en que su cadena lateral es dimetilheptilo en vez de n-hexilo. El primer cannabinoide aislado de Cannabis sativa fue el cannabinol, si bien su estructura fue correctamente caracterizada varios años después. El cannabidiol fue aislado algunos años más tarde y caracterizado posteriormente por Mechoulam y Shvo. Durante 2013, la Academia Nacional de Medicina y la Facultad de Medicina de la Universidad Nacional Autónoma de México, a través del Seminario de Estudios sobre la Globalidad, decidieron realizar una revisión sistemática sobre un tema tan complejo como controvertido: la relación entre la marihuana y la salud. En los últimos años se han realizado estudios con cannabis en varias enfermedades: ensayos clínicos controlados sobre espasticidad en esclerosis múltiple y sobre lesiones medulares, dolor crónico fundamentalmente neuropático y trastornos del movimiento (Gilles de Latourette, distonía, discinesia por levodopa), asma y glaucoma, así como ensayos clínicos no controlados sobre Alzheimer, neuroprotección, hipo intratable, epilepsia, dependencia al alcohol y opioides y procesos inflamatorios.


Asunto(s)
Cannabidiol/aislamiento & purificación , Cannabinoides/uso terapéutico , Cannabis/química , Animales , Cannabidiol/química , Cannabinoides/química , Cannabinoides/aislamiento & purificación , Cannabinol/química , Cannabinol/aislamiento & purificación , Humanos
5.
Cancer ; 124(9): 1946-1953, 2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29461639

RESUMEN

BACKGROUND: The treatment of multiple myeloma (MM) has become costly and difficult to access for patients living in low-income to middle-income countries. METHODS: The current retrospective study included 148 patients in Mexico with newly diagnosed MM, and was performed to compare the outcomes of patients with and without access to novel agents. The records of 77 patients admitted to a public hospital (PubC) and 71 patients cared for within private health systems (PrivC) from November 2007 to July 2016 were reviewed. RESULTS: Compared with those treated in PrivC, patients receiving care at PubC were more likely to be diagnosed with advanced disease. A thalidomide-based regimen was the most common induction treatment used at PubC, whereas a bortezomib-based regimen was used most often in PrivC. The median follow-up was 41 months. Patients in PrivC demonstrated better response rates and survival; 65% of patients treated in PrivC versus 41% treated at PubC achieved a very good partial response or better (P = .005). The median progression-free survival and median overall survival were 23 months and 51 months, respectively, for patients treated at PubC and 41 months and 79 months, respectively, for those treated in PrivC (P<.001). More patients underwent autologous stem cell transplantation in PrivC. When adjustments were made for covariates, patients treated at PubC experienced a higher risk of death compared with patients receiving care in PrivC (hazard ratio, 2.0; 95% confidence interval, 1.0-4.3 [P = .04]). CONCLUSIONS: Stage at diagnosis, induction regimen, and autologous stem cell transplantation were found to be contributors to survival disparities between patients with MM treated at PubC compared with PrivC in Mexico. These findings underscore the need to improve access to novel agents and stem cell transplantation in public health systems. Cancer 2018;124:1946-53. © 2018 American Cancer Society.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Costos de los Medicamentos , Accesibilidad a los Servicios de Salud/economía , Disparidades en Atención de Salud/economía , Trasplante de Células Madre Hematopoyéticas/economía , Mieloma Múltiple/terapia , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/economía , Bortezomib/economía , Bortezomib/uso terapéutico , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Disparidades en Atención de Salud/estadística & datos numéricos , Trasplante de Células Madre Hematopoyéticas/estadística & datos numéricos , Hospitales Privados/economía , Hospitales Privados/estadística & datos numéricos , Hospitales Públicos/economía , Hospitales Públicos/estadística & datos numéricos , Humanos , Masculino , México/epidemiología , Persona de Mediana Edad , Mieloma Múltiple/economía , Mieloma Múltiple/mortalidad , Mieloma Múltiple/patología , Estudios Retrospectivos , Talidomida/economía , Talidomida/uso terapéutico , Trasplante Autólogo/economía , Trasplante Autólogo/estadística & datos numéricos , Resultado del Tratamiento
6.
Mol Phylogenet Evol ; 82 Pt B: 495-510, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24751996

RESUMEN

Using complete mitochondrial genome sequences, we provide the first molecular analysis of the phylogenetic position of the yellow-tailed woolly monkey, Lagothrix flavicauda (a.k.a. Oreonax flavicauda), a critically endangered neotropical primate endemic to northern Perú. The taxonomic status and phylogenetic position of yellow-tailed woolly monkeys have been debated for many years, but in this study both Bayesian and maximum likelihood phylogenetic reconstructions unequivocally support a monophyletic woolly monkey clade that includes L. flavicauda as the basal taxon within the radiation. Bayesian dating analyses using several alternative calibrations suggest that the divergence of yellow-tailed woolly monkeys from other Lagothrix occurred in the Pleistocene, ∼2.1Ma, roughly 6.5 my after the divergence of woolly monkeys from their sister genus, Brachyteles. Additionally, comparative analysis of the cytochrome oxidase subunit 2 (COX2) gene shows that genetic distances between yellow-tailed woolly monkeys and other Lagothrix from across the genus' geographic distribution fall well within the range of between-species divergences seen in a large number of other platyrrhine primate genera at the same locus and outside the range of between-genus divergences. Our results thus confirm a position within Lagothrix for the yellow-tailed woolly monkey and strongly suggest that the name Oreonax be formally considered a synonym for this genus. This revision in taxonomic status does not change the dire conservation threats facing the yellow-tailed woolly monkey in Perú, where the remaining wild population is estimated at only ∼10,000 individuals living in a highly fragmented landscape.


Asunto(s)
Atelidae/clasificación , Evolución Biológica , Filogenia , Animales , Atelidae/genética , Teorema de Bayes , ADN Mitocondrial/genética , Funciones de Verosimilitud , Modelos Genéticos , Perú , Análisis de Secuencia de ADN , América del Sur
7.
Curr Microbiol ; 70(5): 685-9, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25578177

RESUMEN

Helicobacter pylori is considered to be responsible for the most common gastric infections in humans worldwide. In animals, other Helicobacter species are linked to gastritis with and without the presence of ulcers in their respective hosts. Moreover, gastric ulcers have been reported for decades in wild and captive dolphins. Clinical signs include lack of appetite, anorexia, abdominal tenderness, depression, and occasional unresponsiveness. In this study, serum and stool of nine bottlenose dolphins from Loro Parque collection Tenerife, Spain were examined for the presence of Helicobacter spp. The aim of our study was to evaluate the use of two commercially available kits for the detection of H. pylori in humans: a stool antigen immunoassay (Letitest H. pylori CARD) and a Western blot assay (EUROLINE-WB H. pylori) that were adapted to identify specific Helicobacter spp. antibodies in the tested Loro Parque bottlenose dolphin collection. The utility of these diagnostic kits for their application in dolphins is demonstrated, and their use in the future for the diagnosis of Helicobacter spp. in both wild and captive dolphins is proposed in this study.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Antígenos Bacterianos/análisis , Técnicas Bacteriológicas/métodos , Delfín Mular/microbiología , Infecciones por Helicobacter/veterinaria , Helicobacter/aislamiento & purificación , Juego de Reactivos para Diagnóstico , Animales , Heces/microbiología , Helicobacter/inmunología , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/microbiología , Inmunoensayo/métodos , Suero/química , España , Medicina Veterinaria/métodos
9.
Arch Microbiol ; 196(11): 785-90, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25064337

RESUMEN

Erysipelothrix rhusiopathiae is the causative agent of erysipelas, a disease of many mammalian and avian species, mainly swine and turkeys. In cetaceans, erysipelas is considered to be the most common infection in juvenile individuals, which have not been vaccinated. Moreover, the disease manifest in both forms, the dermatologic and the acute septicemic forms, has been reported in various species of dolphins and whales. It is difficult to diagnose erysipelas by currently available approaches. Moreover, it is mainly based on culture methods and also PCR methods, which are currently being developed. At the present stage, prophylactic approaches are based on antibiotic therapy and vaccination mostly with porcine erysipelas vaccines. In the present study, an Indirect Immuno Fluorescence method for the detection of dolphin antibodies levels against E. rhusiopathiae was developed and applied in two different groups of captive bottlenose dolphins (Tursiops truncatus) from Loro Parque (Tenerife, Canary Islands, Spain) and L'Oceanogràfic de Valencia (Valencia, Spain) in order to check the tittering levels of antibodies after application of porcine erysipelas vaccines in the studied dolphins.


Asunto(s)
Animales de Zoológico , Anticuerpos Antibacterianos/sangre , Delfín Mular , Infecciones por Erysipelothrix/inmunología , Erysipelothrix/inmunología , Técnica del Anticuerpo Fluorescente Indirecta/veterinaria , Animales , Vacunas Bacterianas/inmunología , Infecciones por Erysipelothrix/diagnóstico , Femenino , Masculino , España , Vacunación/veterinaria
10.
Parasitol Res ; 113(2): 451-5, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24221890

RESUMEN

The diagnosis of toxoplasmosis is often complicated by the lack of specific clinical symptoms or postmortem features, in humans and other animals. The only diagnostic test described so far for the serological diagnosis of Toxoplasma gondii in marine mammals is the modified agglutination test (Dubey et al., Am J Vet Res 48(8):1239-1243, 1987). The development of more sensible and specific immunological techniques requires specific antibodies, which are currently unavailable in the scientific market. Indirect immunofluorescence (IIF) is one of the most widely used methods for the diagnosis of toxoplasmosis in humans (Auer et al., Parasitol Res 12:965-970, 2000). In order to develop and apply this technique to the bottlenose dolphin (Tursiops truncatus), immunoglobulins were firstly purified using ion-exchange chromatography. The purified immunoglobulins were then injected in New Zealand rabbits in order to obtain polyclonal antibodies. These antisera were validated by the IIF technique, using as controls serum samples of dolphins infected by Toxoplasma. The results were visualized using antirabbit IgG labeled with fluorescein. This newly developed and specific serological assay was then tested with the dolphin collection of Loro Parque, Tenerife, Spain (group I), and L'Oceanogràfic of Valencia, Spain (group II). The obtained results in this study showed that none of the dolphins from group 1 were infected by T. gondii and two animals were positive in group 2. Furthermore, we conclude that this study has produced antibodies with high specificity against dolphin immunoglobulins and an IIF method which may be used as immunological diagnostic tools, especially for the serological diagnosis of toxoplasmosis.


Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Delfín Mular/parasitología , Técnica del Anticuerpo Fluorescente Indirecta , Toxoplasma/inmunología , Toxoplasmosis Animal/diagnóstico , Pruebas de Aglutinación , Animales , Delfín Mular/inmunología , Cromatografía por Intercambio Iónico , Conejos , España , Toxoplasmosis Animal/inmunología
11.
PLoS One ; 19(1): e0296305, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38165899

RESUMEN

Peru ranks among the three countries with the highest bird species diversity globally and a majority of those species are found in the Peruvian Amazon. However, birds in this area are currently facing serious anthropogenic threats. Genetic and genomic methods are becoming important tools for avian biodiversity monitoring and conservation planning. Comprehensive molecular libraries that are publicly available are key to the effective deployment of these tools. We analyze the information gaps for four molecular markers in the most important genetic sequence databases, Barcode of Life Data Systems (BOLD) and NCBI GenBank, for bird species of the Peruvian Amazonia. We found that 64% of Peruvian Amazonian bird species have gene sequences for COI, 59.5% have CYTB sequences, 16.4% have 12S sequences, and only 0.6% have 18S sequences. However, these numbers decrease drastically to 4.3% for COI sequences when we only consider specimens sampled in Peru. Our data also showed that 43.8% of Peruvian Amazonian endemic species (n = 32) are missing sequences of any screened marker uploaded to GenBank or BOLD. Our results will encourage and guide efforts of the scientific community to complete reference libraries for Peruvian avian species that will be useful for future DNA-based monitoring projects that include birds.


Asunto(s)
Biodiversidad , Aves , Animales , Perú , Aves/genética , Brasil
12.
Biochemistry ; 52(40): 7031-40, 2013 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-24033104

RESUMEN

The nitrophorins (NPs) comprise a group of NO transporting ferriheme b proteins found in the saliva of the blood sucking insect Rhodnius prolixus . In contrast to other nitrophorins (NP1-4), the recently identified membrane binding isoform NP7 tends to form oligomers and precipitates at higher concentrations in solution. Hence, solid-state NMR (ssNMR) was employed as an alternative method to gain structural insights on the precipitated protein. We report the expression and purification of (13)C,(15)N isotopically labeled protein together with the first ssNMR characterization of NP7. Because the size of NP7 (21 kDa) still provides a challenge for ssNMR, the samples were reverse labeled with Lys and Val to reduce the number of crosspeaks in two-dimensional spectra. The two electronic spin states with S = 1/2 and S = 0 at the ferriheme iron were generated by the complexation with imidazole and NO, respectively. ssNMR spectra of both forms are well resolved, which allows for sequential resonance assignments of 22 residues. Importantly, the ssNMR spectra demonstrate that aggregation does not affect the protein fold. Comparison of the spectra of the two electronic spin states allows the determination of paramagnetically shifted cross peaks due to pseudocontact shifts, which assists the assignment of residues close to the heme center.


Asunto(s)
Hemoproteínas/química , Proteínas y Péptidos Salivales/química , Animales , Proteínas Portadoras/química , Cristalografía por Rayos X , Proteínas de Unión al Hemo , Hemoproteínas/biosíntesis , Hemoproteínas/aislamiento & purificación , Proteínas de Insectos/biosíntesis , Proteínas de Insectos/química , Proteínas de Insectos/aislamiento & purificación , Resonancia Magnética Nuclear Biomolecular , Multimerización de Proteína , Rhodnius , Proteínas y Péptidos Salivales/biosíntesis , Proteínas y Péptidos Salivales/aislamiento & purificación
13.
Sensors (Basel) ; 13(9): 12406-30, 2013 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-24048336

RESUMEN

The main activity of social robots is to interact with people. In order to do that, the robot must be able to understand what the user is saying or doing. Typically, this capability consists of pre-programmed behaviors or is acquired through controlled learning processes, which are executed before the social interaction begins. This paper presents a software architecture that enables a robot to learn poses in a similar way as people do. That is, hearing its teacher's explanations and acquiring new knowledge in real time. The architecture leans on two main components: an RGB-D (Red-, Green-, Blue- Depth) -based visual system, which gathers the user examples, and an Automatic Speech Recognition (ASR) system, which processes the speech describing those examples. The robot is able to naturally learn the poses the teacher is showing to it by maintaining a natural interaction with the teacher. We evaluate our system with 24 users who teach the robot a predetermined set of poses. The experimental results show that, with a few training examples, the system reaches high accuracy and robustness. This method shows how to combine data from the visual and auditory systems for the acquisition of new knowledge in a natural manner. Such a natural way of training enables robots to learn from users, even if they are not experts in robotics.


Asunto(s)
Inteligencia Artificial , Instrucción por Computador/métodos , Gestos , Relaciones Interpersonales , Sistemas Hombre-Máquina , Robótica/métodos , Software de Reconocimiento del Habla , Comunicación , Cibernética/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Integración de Sistemas
14.
Zootaxa ; 3669: 223-42, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-26312340

RESUMEN

The genus Akodon is one of the most species-rich rodent lineages in South America. In Peru, this genus contains 14 species subdivided in two groups: aerosus and boliviensis. Akodon orophilus Osgood, 1913 (Rodentia: Cricetidae) is a member of the Akodon aerosus group that inhabits the northern Peruvian montane forest, but is poorly characterized and its distribution is vaguely known. We review the status of the species based on morphology, morphometric and karyology, and compared with all members of the Akodon aerosus clade from Peruvian montane forests. As a result, we provide a complete redescription of A. orophilus, present new information on its natural history, restrict its distribution to the east of Río Marai6n, and describe a new species of Akodon from Huánuco Department, central Peru, a population previously assigned to A. orophilus.


Asunto(s)
Distribución Animal , Arvicolinae/anatomía & histología , Arvicolinae/clasificación , Animales , Arvicolinae/genética , Arvicolinae/fisiología , Femenino , Cariotipo , Masculino , Perú , Especificidad de la Especie
15.
Materials (Basel) ; 16(11)2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-37297246

RESUMEN

Oxygen impurities play a crucial role in the glass-forming ability and crystallisation behaviour of metallic glasses. In the present work, single laser tracks were produced on Zr59.3-xCu28.8 Al10.4Nb1.5Ox substrates (x = 0.3, 1.3) to study the redistribution of oxygen in the melt pool under laser melting, which provides the basis for laser powder bed fusion additive manufacturing. Since such substrates are commercially not available, they were fabricated by arc melting and splat quenching. X-ray diffraction revealed that the substrate with 0.3 at.% oxygen was X-ray amorphous, while the substrate with 1.3 at.% oxygen was partially crystalline. Hence, it is evident that the oxygen content affects the crystallisation kinetics. Subsequently, single laser tracks were produced on the surface of these substrates, and the melt pools attained from the laser processing were characterised by atom probe tomography and transmission electron microscopy. Surface oxidation and subsequent convective flow redistribution of oxygen by laser melting were identified as causes of the presence of CuOx and crystalline ZrO nanoparticles in the melt pool. Bands of ZrO likely originate from surface oxides that were moved deeper into the melt pool by convective flow. The findings presented here highlight the influence of oxygen redistribution from the surface into the melt pool during laser processing.

16.
Int J Surg Case Rep ; 108: 108441, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37393679

RESUMEN

INTRODUCTION AND IMPORTANCE: Complications related to silicone oil tamponade are frequent. There are reports of events related to silicone oil (SO) injection during Pars Plana Vitrectomy (PPV). This case presents the unexpected injection of SO in the suprachoroidal space. The proper management of this complication along with the preventive measures are discussed. CASE PRESENTATION: A 38-year-old male presented with a one-week history of decreased vision in his right eye (OD). His visual acuity was hand motion (HM). A late-onset retinal detachment recurrence with proliferative vitreoretinopathy (PVR) in his OD was diagnosed. Cataract surgery and PPV were scheduled. During PPV, a choroidal detachment (CD) secondary to the suprachoroidal injection of silicone oil (SO) was noted. Suprachoroidal SO was identified timely and was managed with external drainage through a posterior sclerotomy. CLINICAL DISCUSSION: Suprachoroidal silicone oil injection is a potential complication during PPV. For the management of this complication, the drainage of the silicone oil from the suprachoroidal space through a posterior sclerotomy may be considered as an option. This complication may be avoided by periodically checking the correct position of the infusion cannula during the PPV, by injecting the SO into the vitreous cavity under direct visualization and by using automated injection systems. CONCLUSION: Suprachoroidal silicone oil injection is an intraoperative complication that might be avoided by cross-checking the correct position of the infusion cannula and by injecting SO under direct visualization.

17.
Proc Biol Sci ; 279(1742): 3384-92, 2012 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-22696521

RESUMEN

Despite extensive culling of common vampire bats in Latin America, lethal human rabies outbreaks transmitted by this species are increasingly recognized, and livestock rabies occurs with striking frequency. To identify the individual and population-level factors driving rabies virus (RV) transmission in vampire bats, we conducted a longitudinal capture-recapture study in 20 vampire bat colonies spanning four regions of Peru. Serology demonstrated the circulation of RV in vampire bats from all regions in all years. Seroprevalence ranged from 3 to 28 per cent and was highest in juvenile and sub-adult bats. RV exposure was independent of bat colony size, consistent with an absence of population density thresholds for viral invasion and extinction. Culling campaigns implemented during our study failed to reduce seroprevalence and were perhaps counterproductive for disease control owing to the targeted removal of adults, but potentially greater importance of juvenile and sub-adult bats for transmission. These findings provide new insights into the mechanisms of RV maintenance in vampire bats and highlight the need for ecologically informed approaches to rabies prevention in Latin America.


Asunto(s)
Anticuerpos Antivirales/sangre , Quirópteros , Ganado , Virus de la Rabia/inmunología , Virus de la Rabia/aislamiento & purificación , Rabia/transmisión , Rabia/veterinaria , Crianza de Animales Domésticos , Animales , Femenino , Técnica del Anticuerpo Fluorescente/veterinaria , Humanos , Masculino , Perú/epidemiología , Densidad de Población , Rabia/epidemiología , Rabia/virología , Estaciones del Año , Estudios Seroepidemiológicos
18.
BMC Ecol ; 12: 1, 2012 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-22284854

RESUMEN

BACKGROUND: The Andes-Amazon basin of Peru and Bolivia is one of the most data-poor, biologically rich, and rapidly changing areas of the world. Conservation scientists agree that this area hosts extremely high endemism, perhaps the highest in the world, yet we know little about the geographic distributions of these species and ecosystems within country boundaries. To address this need, we have developed conservation data on endemic biodiversity (~800 species of birds, mammals, amphibians, and plants) and terrestrial ecological systems (~90; groups of vegetation communities resulting from the action of ecological processes, substrates, and/or environmental gradients) with which we conduct a fine scale conservation prioritization across the Amazon watershed of Peru and Bolivia. We modelled the geographic distributions of 435 endemic plants and all 347 endemic vertebrate species, from existing museum and herbaria specimens at a regional conservation practitioner's scale (1:250,000-1:1,000,000), based on the best available tools and geographic data. We mapped ecological systems, endemic species concentrations, and irreplaceable areas with respect to national level protected areas. RESULTS: We found that sizes of endemic species distributions ranged widely (< 20 km2 to > 200,000 km2) across the study area. Bird and mammal endemic species richness was greatest within a narrow 2500-3000 m elevation band along the length of the Andes Mountains. Endemic amphibian richness was highest at 1000-1500 m elevation and concentrated in the southern half of the study area. Geographical distribution of plant endemism was highly taxon-dependent. Irreplaceable areas, defined as locations with the highest number of species with narrow ranges, overlapped slightly with areas of high endemism, yet generally exhibited unique patterns across the study area by species group. We found that many endemic species and ecological systems are lacking national-level protection; a third of endemic species have distributions completely outside of national protected areas. Protected areas cover only 20% of areas of high endemism and 20% of irreplaceable areas. Almost 40% of the 91 ecological systems are in serious need of protection (= < 2% of their ranges protected). CONCLUSIONS: We identify for the first time, areas of high endemic species concentrations and high irreplaceability that have only been roughly indicated in the past at the continental scale. We conclude that new complementary protected areas are needed to safeguard these endemics and ecosystems. An expansion in protected areas will be challenged by geographically isolated micro-endemics, varied endemic patterns among taxa, increasing deforestation, resource extraction, and changes in climate. Relying on pre-existing collections, publically accessible datasets and tools, this working framework is exportable to other regions plagued by incomplete conservation data.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales/métodos , Demografía , Ecosistema , Modelos Teóricos , Animales , Bolivia , Geografía , Mapas como Asunto , Perú , Especificidad de la Especie
19.
Int J Psychol Res (Medellin) ; 15(2): 105-113, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-37274521

RESUMEN

The objective of the study was to evaluate the psychometric properties of the European Bullying Intervention Project Questionnaire (EBIPQ) inPeruvian adolescents and to determine gender-specific differences. The sample comprised 532 students in sixth grade of elementary school to third grade of high school. To validate the instrument, we requested an expert judgement and conducted a pilot test. Subsequently, we performed the exploratory factorial analysis, which showed that all the questions were correctly loaded in both components, an aspect that explained the 48.6%variance. We determined the reliability by means of the internal-consistency method using the Cronbach's alfa (αtotal= .856;αvictimization= .807;αaggression= .828). We found gender-specific differences in bullying roles(p<.001). In conclusion, the factorial structure of the EBIPQ in Peruvian adolescents is similar to the original questionnaire and presents high reliability and construct validity.


El estudio tuvo como objetivo evaluar las propiedades psicométricas del European Bullying Intervention Project Questionnaire (EBIPQ) en adolescentes peruanos y determinar sus diferencias según el género. La muestra estuvo conformada por 532 escolares de sexto grado de Primaria a tercer grado de Secundaria. Para la validez del contenido, se realizó el juicio de expertos y una prueba piloto. Posteriormente, se realizó el análisis factorial exploratorio, el cual mostró que todas las preguntas fueron cargadas en forma correcta en los dos componentes, lo que explica el 48.6% de varianza. La confiabilidad se estableció mediante el método de consistencia interna, a través del Alfa de Cronbach (αtotal=.856;αvictimización= .807;αagresión= .828). Se encontraron diferenciasen el rol de acoso escolar según el género (p<.001).En conclusión, la estructura factorial del EBIPQ en adolescentes peruanos es similar al cuestionario original y presenta elevada confiabilidad y validez de constructo.

20.
Menopause ; 29(3): 317-326, 2022 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-35213519

RESUMEN

OBJECTIVE: To assess the association between menopausal status and female sexual function among mid-aged women with human immunodeficiency virus (HIV) infection. METHODS: We carried out a cross-sectional study of 221 sexually active HIV-infected women ages 40 to 59 years, based on a secondary analysis of a three-hospital survey in Lima, Perú. We classified menopausal status according to Stages of Reproductive Aging Workshop criteria (STRAW+10); this exposure variable was categorized as binary (non-postmenopausal and postmenopausal) and-for exploratory analysis-as multinomial (pre-, peri-, and postmenopausal). We defined low sexual function (LSF) using the 6-item Female Sexual Function Index (total score ≤19). Socio-demographic and clinical variables were assessed, including age, used highly active antiretroviral therapy scheme, disease duration, depressive symptoms, and co-morbidities. We performed Poisson generalized linear models with a robust variance to estimate 95% confidence interval (CI), crude prevalence ratios (cPRs), and adjusted prevalence ratios (aPRs) by epidemiological and statistical approaches using nonparametric method of bias-corrected and accelerated bootstrap resampling with 1,000 repetitions. RESULTS: Studied women had a median age of 47.0 years (interquartile range: 7.5); 25.3% were premenopausal, 25.8% were perimenopausal, and 48.9% were postmenopausal. Also, 64.3% had LSF. The frequency of LSF was 53.6% in non-postmenopausal and 75.0% in postmenopausal women. Postmenopausal status was associated with LSF in both the crude (cPR = 1.39; 95% CI: 1.13-1.71) and the adjusted regression models (aPR = 1.38; 95% CI: 1.12-1.71). CONCLUSIONS: HIV-infected postmenopausal women have a higher prevalence of LSF than those non-postmenopausal ones, even when adjusting for multiple potential confounders.


Asunto(s)
Terapia Antirretroviral Altamente Activa , Infecciones por VIH , Adulto , Estudios Transversales , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Menopausia , Persona de Mediana Edad , Premenopausia , Encuestas y Cuestionarios
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