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1.
Acta Ortop Mex ; 37(4): 237-243, 2023.
Artigo em Espanhol | MEDLINE | ID: mdl-38373735

RESUMO

INTRODUCTION: atlas assimilation can occur alone or in association with other craniocervical junction malformations and deformities. The etiological and pathological mechanisms are not clear. CASE PRESENTATION: patient in her sixth decade of life, who was treated at the "Eugenio Espejo" Hospital, with asymmetric pyramidal symptoms after a low-energy kinetic fall. The condition completely reverted with conservative management. The patient is currently under periodic observation. CONCLUSION: the atlas assimilation, a congenital malformation, often asymptomatic; it is part of an embryological compensation when it is associated with other malformations. The appearance of deformity is necessary to reach atlantoaxial instability that it is not early. The knowledge of the concepts and distinction of the craniocervical junction abnormalities allows to indicate the best treatment in order to obtain the most suitable results with the individualization of each case.


INTRODUCCIÓN: la asimilación atlantoidea puede presentarse sola o asociada a otras malformaciones y deformidades de la unión craneocervical, los mecanismos etiológicos y patológicos no están esclarecidos. PRESENTACIÓN DE CASO: paciente de la sexta década de vida, quien fue atendida en el Hospital de Especialidades "Eugenio Espejo", con datos clínicos piramidales asimétricos, posteriores a mecanismo de lesión de caída con cinética de baja energía. La sintomatología revirtió con manejo conservador. En la actualidad, la paciente está bajo observación periódica. CONCLUSIÓN: la asimilación atlantoidea es una malformación congénita muchas veces asintomática y parte de una compensación embriológica cuando está asociada a otras malformaciones. Es necesaria la aparición de deformidad para llegar a la inestabilidad atlantoaxoidea que no es temprana. El conocimiento y poder diferenciar los conceptos de las anormalidades de la unión craneocervical permiten indicar el mejor tratamiento y así obtener los resultados más adecuados con la individualización de cada caso.


Assuntos
Instabilidade Articular , Doenças da Coluna Vertebral , Fusão Vertebral , Humanos , Feminino , Instabilidade Articular/cirurgia , Descompressão Cirúrgica
2.
PLoS One ; 16(10): e0255555, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34613994

RESUMO

The jaguar (Panthera onca) is one of the most threatened carnivores in the Americas. Despite a long history of research on this charismatic species, to date there have been few systematic efforts to assess its population size and status in most countries across its distribution range. We present here the results of the two National Jaguar Surveys for Mexico, the first national censuses in any country within the species distribution. We estimated jaguar densities from field data collected at 13 localities in 2008-2010 (2010 hereafter) and 11 localities in 2016-2018 (2018 hereafter). We used the 2010 census results as the basis to develop a National Jaguar Conservation Strategy that identified critical issues for jaguar conservation in Mexico. We worked with the Mexican government to implement the conservation strategy and then evaluated its effectivity. To compare the 2010 and 2018 results, we estimated the amount of jaguar-suitable habitat in the entire country based on an ecological niche model for both periods. Suitable jaguar habitat covered ~267,063 km2 (13.9% of the country's territory) in 2010 and ~ 288,890 km2 (~14.8% of the country's territory) in 2018. Using the most conservative density values for each priority region, we estimated jaguar densities for both the high and low suitable habitats. The total jaguar population was estimated in ~4,000 individuals for 2010 census and ~4,800 for the 2018 census. The Yucatan Peninsula was the region with the largest population, around 2000 jaguars, in both censuses. Our promising results indicate that the actions we proposed in the National Jaguar Conservation Strategy, some of which have been implemented working together with the Federal Government, other NGO's, and land owners, are improving jaguar conservation in Mexico. The continuation of surveys and monitoring programs of the jaguar populations in Mexico will provide accurate information to design and implement effective, science-based conservation measures to try to ensure that robust jaguar populations remain a permanent fixture of Mexico's natural heritage.


Assuntos
Conservação dos Recursos Naturais/legislação & jurisprudência , Panthera/fisiologia , Política Pública/legislação & jurisprudência , Animais , Ecossistema , México , Densidade Demográfica
3.
Conserv Biol ; 34(1): 207-219, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31385631

RESUMO

Habitat fragmentation is a primary driver of wildlife loss, and establishment of biological corridors is a common strategy to mitigate this problem. A flagship example is the Mesoamerican Biological Corridor (MBC), which aims to connect protected forest areas between Mexico and Panama to allow dispersal and gene flow of forest organisms. Because forests across Central America have continued to degrade, the functioning of the MBC has been questioned, but reliable estimates of species occurrence were unavailable. Large mammals are suitable indicators of forest functioning, so we assessed their conservation status across the Isthmus of Panama, the narrowest section of the MBC. We used large-scale camera-trap surveys and hierarchical multispecies occupancy models in a Bayesian framework to estimate the occupancy of 9 medium to large mammals and developed an occupancy-weighted connectivity metric to evaluate species-specific functional connectivity. White-lipped peccary (Tayassu pecari), jaguar (Panthera onca), giant anteater (Myrmecophaga tridactyla), white-tailed deer (Odocoileus virginianus), and tapir (Tapirus bairdii) had low expected occupancy along the MBC in Panama. Puma (Puma concolor), red brocket deer (Mazama temama), ocelot (Leopardus pardalis), and collared peccary (Pecari tajacu), which are more adaptable, had higher occupancy, even in areas with low forest cover near infrastructure. However, the majority of species were subject to ≥1 gap that was larger than their known dispersal distances, suggesting poor connectivity along the MBC in Panama. Based on our results, forests in Darien, Donoso-Santa Fe, and La Amistad International Park are critical for survival of large terrestrial mammals in Panama and 2 areas need restoration.


Efectividad de Panamá como un Puente Terrestre Intercontinental para Mamíferos Mayores Resumen La fragmentación del hábitat es un causante primario de la pérdida de biodiversidad, y el establecimiento de corredores biológicos es una estrategia común para mitigar este problema. El Corredor Biológico Mesoamericano (CBM) es un ejemplo notable que pretende conectar áreas boscosas protegidas entre México y Panamá para permitir la dispersión y flujo genético de organismos del bosque. El funcionamiento del CBM se ha cuestionado debido a que la degradación de los bosques en Centroamérica continúa, pero no se dispone de estimaciones confiables de la ocurrencia de especies. Los mamíferos grandes son indicadores adecuados del funcionamiento de los bosques tropicales Por lo tanto evaluamos su estado de conservación en el Istmo de Panamá, la sección más angosta del CBM. Utilizamos muestreos con cámaras trampa y modelos de ocupación para múltiples especies bajo un modelo Bayesiano para estimar la ocupación de 9 especies de mamíferos medianos a grandes, y desarrollamos una métrica de conectividad ponderada por la ocupación para evaluar la conectividad funcional para cada especie. El puerco de monte (Tayassu pecari), jaguar (Panthera onca), hormiguero gigante (Myrmecophaga tridactyla), venado cola blanca (Oidocoileus virginianus), y tapir (Tapirus bairdii) presentaron una ocupación baja en el CBM en Panamá. El puma (Puma concolor), venado corzo (Mazama temama), ocelote (Leopardus pardalis) y el saino (Pecari tajacu), que son más adaptables, presentaron mayor ocupación, aún en áreas con poca cobertura boscosa, cercanas a infraestructura. Sin embargo, la mayoría de las especies estuvo sujeta a ≥ 1 vacío que era mayor que sus distancias de dispersión conocidas, lo que sugiere una conectividad pobre a lo largo del CBM en Panamá. Basados en nuestros resultados, los bosques de Darién, Donoso-Santa Fé y el Parque Internacional La Amistad son críticos para la supervivencia de mamíferos terrestres grandes en Panamá mientras que 2 áreas requieren restauración.


Assuntos
Conservação dos Recursos Naturais , Cervos , Animais , Teorema de Bayes , América Central , Ecossistema , Florestas , Mamíferos , México , Panamá
4.
BMC Genet ; 20(1): 100, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31881935

RESUMO

BACKGROUND: Connectivity among jaguar (Panthera onca) populations will ensure natural gene flow and the long-term survival of the species throughout its range. Jaguar conservation efforts have focused primarily on connecting suitable habitat in a broad-scale. Accelerated habitat reduction, human-wildlife conflict, limited funding, and the complexity of jaguar behaviour have proven challenging to maintain connectivity between populations effectively. Here, we used non-invasive genetic sampling and individual-based conservation genetic analyses to assess genetic diversity and levels of genetic connectivity between individuals in the Cockscomb Basin Wildlife Sanctuary and the Maya Forest Corridor. We used expert knowledge and scientific literature to develop models of landscape permeability based on circuit theory with fine-scale landscape features as ecosystem types, distance to human settlements and roads to predict the most probable jaguar movement across central Belize. RESULTS: We used 12 highly polymorphic microsatellite loci to identify 50 individual jaguars. We detected high levels of genetic diversity across loci (HE = 0.61, HO = 0.55, and NA = 9.33). Using Bayesian clustering and multivariate models to assess gene flow and genetic structure, we identified one single group of jaguars (K = 1). We identified critical areas for jaguar movement that fall outside the boundaries of current protected areas in central Belize. We detected two main areas of high landscape permeability in a stretch of approximately 18 km between Sittee River Forest Reserve and Manatee Forest Reserve that may increase functional connectivity and facilitate jaguar dispersal from and to Cockscomb Basin Wildlife Sanctuary. Our analysis provides important insights on fine-scale genetic and landscape connectivity of jaguars in central Belize, an area of conservation concern. CONCLUSIONS: The results of our study demonstrate high levels of relatively recent gene flow for jaguars between two study sites in central Belize. Our landscape analysis detected corridors of expected jaguar movement between the Cockscomb Basin Wildlife Sanctuary and the Maya Forest Corridor. We highlight the importance of maintaining already established corridors and consolidating new areas that further promote jaguar movement across suitable habitat beyond the boundaries of currently protected areas. Continued conservation efforts within identified corridors will further maintain and increase genetic connectivity in central Belize.


Assuntos
Variação Genética , Genética Populacional/métodos , Panthera/genética , Animais , Belize , Conservação dos Recursos Naturais , Ecossistema , Evolução Molecular , Fluxo Gênico , Repetições de Microssatélites
5.
J Chem Phys ; 150(14): 144104, 2019 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-30981239

RESUMO

The theory of nonlocal isothermal hydrodynamics near a solid object derived microscopically in the study by Camargo et al. [J. Chem. Phys. 148, 064107 (2018)] is considered under the conditions that the flow fields are of macroscopic character. We show that in the limit of macroscopic flows, a simple pillbox argument implies that the reversible and irreversible forces that the solid exerts on the fluid can be represented in terms of boundary conditions. In this way, boundary conditions are derived from the underlying microscopic dynamics of the fluid-solid system. These boundary conditions are the impenetrability condition and the Navier slip boundary condition. The Green-Kubo transport coefficients associated with the irreversible forces that the solid exert on the fluid appear naturally in the slip length. The microscopic expression for the slip length thus obtained is shown to coincide with the one provided originally by Bocquet and Barrat [Phys. Rev. E 49, 3079 (1994)].

6.
J Chem Phys ; 148(6): 064107, 2018 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-29448792

RESUMO

Density Functional Theory (DFT) is a successful and well-established theory for the study of the structure of simple and complex fluids at equilibrium. The theory has been generalized to dynamical situations when the underlying dynamics is diffusive as in, for example, colloidal systems. However, there is no such a clear foundation for Dynamic DFT (DDFT) for the case of simple fluids in contact with solid walls. In this work, we derive DDFT for simple fluids by including not only the mass density field but also the momentum density field of the fluid. The standard projection operator method based on the Kawasaki-Gunton operator is used for deriving the equations for the average value of these fields. The solid is described as featureless under the assumption that all the internal degrees of freedom of the solid relax much faster than those of the fluid (solid elasticity is irrelevant). The fluid moves according to a set of non-local hydrodynamic equations that include explicitly the forces due to the solid. These forces are of two types, reversible forces emerging from the free energy density functional, and accounting for impenetrability of the solid, and irreversible forces that involve the velocity of both the fluid and the solid. These forces are localized in the vicinity of the solid surface. The resulting hydrodynamic equations should allow one to study dynamical regimes of simple fluids in contact with solid objects in isothermal situations.

7.
Ginecol Obstet Mex ; 84(3): 164-71, 2016 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-27424442

RESUMO

BACKGROUND: Fetal macrosomia is birth weight of 4,000 grams or more, regardless of gestational age, in Mexico representing about 5.4%. Associated with multiple demographic, physiological, metabolic and genetic factors of each population. OBJECTIVE: Determine the risk factors associated with the development of fetal macrosomia in patients without gestational diabetes mellitus. METHODS: Retrospective, descriptive and comparative study of patients who came to delivery from January 2012 to June 2014, 88 patients, 23 patients with diagnosis of macrosomia, and 65 patients without macrosomia without gestational diabetes mellitus were included. RESULTS: An incidence of fetal macrosomia of 18.6%. Risk factors such as parity, history of fetal macrosomia, maternal age, maternal height more to 1.70 meters showed no difference, the percentage of overweight 105% showed 69% vs 52% on the control group and gestational diabetes screening altered that present 30.4 vs 20%. CONCLUSIONS: Increased incidence of macrosomia was demonstrated in patients with metabolic factors such as the percentage of overweight and screening altered gestational diabetes mellitus, as they showed higher prevalence in the study group, all modifiable with preconception nutritional management and during pregnancy, to reduce initial weight and weight gain, improved fasting and postprandial blood glucose in patients with positive screening and negative tolerance curve carbohydrates to maintain fetal growth curve with in the percentiles.


Assuntos
Macrossomia Fetal/epidemiologia , Adolescente , Adulto , Diabetes Gestacional , Feminino , Humanos , Gravidez , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
8.
Ginecol Obstet Mex ; 84(3): 172-9, 2016 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-27424443

RESUMO

BACKGROUND: The vulvar cancer is the fourth more frequent neoplasia after the endometrial, cervix and ovarian cancer. Normally, it has been related to old women of ages from 70 to 80 years old. Rarely, it has been detected cases in adult or young women. However, its incidence has been increased in the last years and in more early years. It is for this change in the incidence and its appearance in early years why a possible etiology has been looked for, opening different hypothesis that go from that related to the HPV to those that study an inflammatory chronic process as the basis for the carcinogenesis. CLINICAL CASE: In this article, it has been presented the case of a woman who is 34 years old with negative VPH that made her debut with epidermoid carcinoma of the vulva moderately different and on purpose of the case, we do a revision of the literature existent. CONCLUSIONS: Vulvar cancer diagnosed in young women as in older, but with different trends, risk factors and natural history. The case reported here escapes the theories studied so far so needed new lines of inquiry to investigate this form of presentation young woman, without HPV infection.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Vulvares , Adulto , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Feminino , Humanos , Infecções por Papillomavirus , Neoplasias Vulvares/patologia , Neoplasias Vulvares/cirurgia
9.
Ginecol Obstet Mex ; 84(2): 112-21, 2016 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-27323417

RESUMO

BACKGROUND: Uterine fibroids are the most common gynecological tumors; the prevalence increases with age. They can cause symptoms (20-50%). Myomectomy is an alternative for women who wish to preserve their fertility, increased risk of blood loss and longer operative time. Since 2000, a significant number of surgeons have performed occlusion of uterine arteries prior to myomectomy successfully. CASE REPORT: We report the case of a 24-year-old patient, with a history of premature birth; and starts her condition after obstetric event with abnormal uterine bleeding and postcoital bleeding, accompanied by intense, oppressive and stabbing abdominal pain and increased ab-dominal volume. At physical examination an enlarged abdominal wall by a tumor involving, abdominal pain on palpation, at the gynecological examination: frankly enlarged uterus, about 25 x 20 cm, painful and tenderness. Prior to myomectomy, uterine externalization takes place and proceeds to dearterialization of uterine arteries under the García-González technique, removing the tumor without complications, with an estimated 100 cc bleeding. The bilateral uterine artery ligation, is one of the methods used to re-duce intraoperative blood loss. It is a quick, simple technique, whose theoretical basis is that 90% of the irrigation of the uterus comes from the uterine arteries.


Assuntos
Leiomioma/cirurgia , Artéria Uterina/cirurgia , Miomectomia Uterina/métodos , Neoplasias Uterinas/cirurgia , Dor Abdominal/etiologia , Perda Sanguínea Cirúrgica/prevenção & controle , Feminino , Humanos , Leiomioma/patologia , Ligadura , Neoplasias Uterinas/patologia , Adulto Jovem
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