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1.
J Am Chem Soc ; 142(30): 12987-12994, 2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32627546

RESUMO

We report the synthesis and characterization of a new class of 2D-covalent organic frameworks, called COFamides, whose layers are held together by amide hydrogen bonds. To accomplish this, we have designed monomers with a nonplanar structure that arises from steric crowding, forcing the amide side groups out of plane with the COF sheets orienting the hydrogen bonds between the layers. The presence of these hydrogen bonds provides significant structural stabilization as demonstrated by comparison to control structures that lack hydrogen bonding capability, resulting in lower surface area and crystallinity. We have characterized both azine and imine-linked versions of these COFs, named COFamide-1 and -2, respectively, for their surface areas, pore sizes, and crystallinity. In addition to these more conventional characterization methods, we also used variable temperature infrared spectroscopy methods and van der Waals density functional calculations to directly observe the presence of hydrogen bonding.

2.
Rev Med Chil ; 147(1): 47-52, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-30848764

RESUMO

BACKGROUND: Cardiovascular complications can occur in up to 80% of adolescent patients with eating disorders (ED) and account for 30% of their mortality. AIM: To evaluate cardiovascular complications in adolescents with ED and their evolution after refeeding. PATIENTS AND METHODS: In adolescents with ED admitted to treatment, we assessed the nutritional status, weight loss prior to consultation, presence of bradycardia (BC, defined as heart rate < 60 bpm), we performed an electrocardiogram (ECG) and an echocardiography and measured thyroid hormones. RESULTS: We studied 53 women aged 16.4 ± 2.3 years. Fifteen had a diagnosis of Anorexia Nervosa (AN), seven of Bulimia (BN), eight a not otherwise specified ED (ED-NOS), four a Binge Eating Disorder (BED), sixteen an Atypical Anorexia (AAN) and three an Atypical Bulimia (ABN). Thirty four percent were malnourished and 3.8% overweight. The most common cardiac problem was BC in 51%. In eight of 26 patients in whom an echocardiogram was done, it was abnormal. Six had a decreased ventricular mass, three a pericardial effusion and three valvular involvement. There was a significant association between bradycardia and malnutrition, weight loss and low free triiodothyronine levels. BC was significantly more common in patients with AN, but it also occurred in half of the patients with AAN and in one of three patients with other types of ED. At follow up, bradycardia significantly improved with refeeding. CONCLUSIONS: There is an association between all types of ED and bradycardia, as well as anatomical and functional cardiac anomalies.


Assuntos
Bradicardia/etiologia , Transtornos da Alimentação e da Ingestão de Alimentos/complicações , Adolescente , Análise de Variância , Índice de Massa Corporal , Bradicardia/fisiopatologia , Criança , Estudos de Coortes , Ecocardiografia , Eletrocardiografia , Transtornos da Alimentação e da Ingestão de Alimentos/fisiopatologia , Feminino , Humanos , Desnutrição/complicações , Desnutrição/fisiopatologia , Fatores de Risco , Estatísticas não Paramétricas , Redução de Peso/fisiologia , Adulto Jovem
3.
Am J Dermatopathol ; 38(4): 302-4, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26999341

RESUMO

INTRODUCTION: Cutaneous metastases represent 2% of all metastases. Breast cancer is the most common cause of skin metastases. Schwartz described 8 types of cutaneous breast metastases; one uncommon form is carcinoma telangiectodes (CT), which may resemble angiosarcoma or lymphangioma circumscriptum. However, there are no reports of CT misdiagnosed as eruptive angiokeratomas. CASE REPORT: The authors describe the clinical, histopathologic, and immunohistochemical features of a unique case of CT. Clinical examination revealed an itchy, dark blue-reddish scaly papular eruption that resembled angiokeratomas. The papules were grouped in a zosteriform pattern on the right chest. A biopsy of the papules revealed intravascular thrombi of neoplastic cells and erythrocytes. The neoplastic cells were pleomorphic and with mitotic figures. Immunohistochemical analysis revealed expression of HER-2-neu in neoplastic cells but negative for estrogen and progesterone receptors. The involved vessels were positive for CD31 and negative for podoplanin. This immunoprofile demonstrated intravascular spread of aggressive breast carcinoma. CONCLUSION: CT is an uncommon form of cutaneous metastasis from breast carcinoma with less than 10 cases described in the literature. There are no previous reported cases of CT mimicking angiokeratomas, although lymphangioma circumscriptum-like lesion may occasionally resemble angiokeratomas. A unique clinical presentation of CT is described.


Assuntos
Angioceratoma/diagnóstico , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/secundário , Erros de Diagnóstico , Neoplasias Cutâneas/secundário , Biópsia , Feminino , Humanos , Pessoa de Meia-Idade
4.
Rev Biol Trop ; 62(1): 165-72, 2014 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-24912351

RESUMO

Population ecology of Crocodylus acutus (Reptilia: Crocodylidae) in Palmasola lagoon, Oaxaca, Mexico. Abundance and population structure are important parameters to evaluate and compare the conservation status of a population over time in a given area. This study describes the population abundance and structure of Crocodylus acutus in Palmasola lagoon, Oaxaca. The field works consisted of night surveys during the new moon phase, between the 21:00 and 24:00h. These were conducted during the dry and wet seasons and counted the number of individuals to obtain population estimates. Recorded encounter rates ranged from 32 to 109.3ind./ km in 40 journeys deployed with an average time of 18 minutes browsing. The estimated population size using the Messel's model ranged from 32.7 to 93 individuals. For both seasons, there was a marked dominance of subadults, followed by juveniles and to a lesser extent adult individuals, as well as undetermined individuals (i.e. unknown body/size/length), in both seasons. There was also a significant association with mangrove areas (26.1%) by juveniles; the subadults's individual use of superficial water (22.7%) and mangrove areas (15.7%); meanwhile the adults were observed on superficial water (9.7%). This information contributes to our understanding of the population ecology of C. acutus in the Palmasola lagoon where the estimated population size seems to show higher values when compared to other reports in the country.


Assuntos
Jacarés e Crocodilos/classificação , Animais , Ecossistema , Lagos , México , Densidade Demográfica , Estações do Ano
5.
Environ Sci Pollut Res Int ; 31(7): 10911-10919, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38214861

RESUMO

Persistent organic pollutants (POPs) are chemical substances widely distributed in the environment by the runoff from anthropic activities and can be distributed and bioaccumulated or biomagnified in the environment, affecting the health of organisms. The sea turtle, Lepidochelys olivacea, is a long-lived organism, with migratory habits and feeding behaviors that allow exposure to various pollutants. This work aimed to determine long-term exposure to POPs in adult olive ridley turtles (L. olivacea), sampled during the nesting season, in "La Escobilla" Sanctuary. Blood samples were collected and processed to obtain plasma. The quantification of POPs in blood was carried out with an extraction technique with a focused ultrasound probe. Twenty-seven POP analytes were determined. The concentrations of hexachlorocyclohexane, endosulfan isomers, dichlorodiphenyltrichloroethane, total polychlorinated biphenyls, and the total sum of POPs found in plasma are higher than those reported in other studies, which reported effects such as hematological and biochemical changes in blood, changes in immune system cells and enzymatic activity related to oxidative stress. These results are important to demonstrate the chronic exposure to POPs in olive ridley turtles in marine ecosystems and to highlight the importance of assessing the associated health risks, considering that these contaminants could be transferred to the offspring and affect future generations of this reptile. It is important to carry out studies that develop conservation strategies for the olive ridley turtle. Also, it is necessary to control the emissions of pollutants into the atmosphere, as well as reduce urban, agricultural, and industrial waste in the environment and marine ecosystems.


Assuntos
Poluentes Ambientais , Olea , Tartarugas , Animais , Poluentes Orgânicos Persistentes , Ecossistema , México
7.
Front Vet Sci ; 10: 1321172, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38362467

RESUMO

Introduction: Herpesvirus infections have been highlighted as emerging diseases affecting wildlife health and the conservation of several taxa. Malignant catarrhal fever (MCF) and infectious keratoconjunctivitis (IKC) are two viruses that infect wild ruminants. Nevertheless, epidemiological data on herpesviruses in South American wild ruminants are limited. An outbreak of caprine gammaherpesvirus-2 (CpHV-2) that recently was suspected as the cause of MCF in southern pudus (Pudu puda) prompted the need to conduct molecular screenings in Chilean cervids to understand the epidemiology of herpesviruses. The aim of this study was to determine the occurrence and genetic diversity of herpesviruses in free-ranging cervids from Chile. Methods: Herpesvirus infection was assessed in antemortem blood samples (n = 86) from pudus (n = 81) and huemuls (Hippocamelus bisulcus) (n = 5), as well as postmortem samples of spleen (n = 24) and lung (n = 3) from pudus, using a nested pan-herpesvirus PCR assay. Results: Combining all suitable sample types, DNA of pudu gammaherpesvirus-1 was detected in five pudues and five huemuls, with an overall prevalence of 9.90% (n = 10/101; 95% CI = 5.11-17.87%). One pudu tested positive for ovine gammaherpesvirus-2 (n = 1/96; 1.04%; 95% CI = 0.05-6.49%), and one pudu tested positive for a Macavirus sequence with 98.63 similarity to ovine gammaherpesvirus-2 (n = 96; 1.04%; 95% CI = 0.05-6.49%). Discussion: To the best of our knowledge, this is the first report of a herpesvirus in huemul and of ovine gammaherpesvirus-2 in Chile. Our results also confirm the active circulation of herpesvirus in free-ranging cervids in Chilean Patagonia, and as such, MCF should be considered as a possible cause of disease in free-ranging Chilean pudus and livestock species. Further research is necessary to develop a plan of systematic monitoring (serological and pathological screening) of herpesviruses in Chilean wild and domestic ruminants to understand their diversity and impact on animal health and conservation.

8.
Curr Med Chem ; 29(6): 1124-1141, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34814808

RESUMO

BACKGROUND: Worldwide, the prevalence of obesity and related non-communicable chronic diseases is high and continues to grow. In that sense, anthocyanins (ANC) have shown beneficial health effects in preventing obesity and metabolic risk factors. Moreover, the demand for functional foods incorporating these compounds has risen significantly in the past years. Thus, there is a need for validations of the functional properties of these formulations; nevertheless, in vivo assays are complex and require a lot of resources. One approach for estimating bioactive compounds' functionality and health benefits is to evaluate their bioaccessibility on a specific food matrix, determined by various factors. This article aims to review different factors influencing the bioaccessibility of ANC evaluated on in vitro digestion models as a functionality parameter, elucidating the effect of chemical composition, raw materials, food matrices, and vehicles for the delivery of ANC. METHODS: Study searches were performed using PubMed, Web of Science, Scopus, and Science Direct databases. RESULTS: Different factors influenced bioaccessibility and stability of ANC studied by in vitro digestion: i) the raw material used for ANC obtention; ii) food processing; iii) other food components; iv) the extraction method and solvents used; v) the structure of ANC; vi) delivery system (e.g., microencapsulation); vii) pH of the medium; viii) the digestion stage. CONCLUSION: Simulated digestion systems allow to determine free or encapsulated ANC bioaccessibility in different food matrices, which offers advantages in determining the potential functionality of a food product.


Assuntos
Antocianinas , Alimento Funcional , Antocianinas/química , Antioxidantes/química , Disponibilidade Biológica , Digestão , Manipulação de Alimentos , Humanos
9.
J Wildl Dis ; 58(3): 680-684, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35512300

RESUMO

Screening of serum and fecal samples from huemul (Hippocamelus bisulcus) and pudu (Pudu puda) from southern Chile for Mycobacterium bovis and Mycobacterium avium paratuberculosis (MAP) found all but four samples Mycobacterium-negative. The positive sequences showed only 92-93% similarity with MAP and were from remote Isla Riesco populations.


Assuntos
Doenças dos Bovinos , Cervos , Mycobacterium avium subsp. paratuberculosis , Mycobacterium bovis , Paratuberculose , Tuberculose Bovina , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Chile/epidemiologia , Paratuberculose/epidemiologia , Tuberculose Bovina/diagnóstico
10.
ACS Macro Lett ; 10(4): 486-491, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35549222

RESUMO

Dynamic covalent bonds impart new properties to 3D printable materials that help to establish 3D printing as an accessible and efficient manufacturing technique. Here, we studied the effect of a thermally reversible Diels-Alder cross-linker on the shape stability of photoprintable resins and their self-healing properties. Resins containing different concentrations of dynamic covalent cross-links in a polyacrylate network showed that the content of dynamic cross-links plays a key role in balancing shape stability with self-healing ability. The shape stability of the printed objects was evaluated by measuring the dimensional changes after thermal treatment. The self-healing efficiency of the 3D printed resins was characterized with a scratch test and tensile testing. A dynamic covalent cross-link concentration of 1.8 mol % was enough to provide 99% self-healing efficiency without disrupting the shape stability of the printed objects. Our work shows the potential of dynamic covalent bonds in broadening the availability of 3D printable materials that are compatible with vat photopolymerization.

11.
Nat Commun ; 12(1): 2202, 2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33850135

RESUMO

Artificial native-like lipid bilayer systems constructed from phospholipids assembling into unilamellar liposomes allow the reconstitution of detergent-solubilized transmembrane proteins into supramolecular lipid-protein assemblies called proteoliposomes, which mimic cellular membranes. Stabilization of these complexes remains challenging because of their chemical composition, the hydrophobicity and structural instability of membrane proteins, and the lability of interactions between protein, detergent, and lipids within micelles and lipid bilayers. In this work we demonstrate that metastable lipid, protein-detergent, and protein-lipid supramolecular complexes can be successfully generated and immobilized within zeolitic-imidazole framework (ZIF) to enhance their stability against chemical and physical stressors. Upon immobilization in ZIF bio-composites, blank liposomes, and model transmembrane metal transporters in detergent micelles or embedded in proteoliposomes resist elevated temperatures, exposure to chemical denaturants, aging, and mechanical stresses. Extensive morphological and functional characterization of the assemblies upon exfoliation reveal that all these complexes encapsulated within the framework maintain their native morphology, structure, and activity, which is otherwise lost rapidly without immobilization.


Assuntos
Detergentes/química , Exoesqueleto Energizado , Imobilização/métodos , Bicamadas Lipídicas/química , Proteínas de Membrana/química , Membrana Celular , ATPases Transportadoras de Cobre , Proteínas de Escherichia coli , Cinética , Bicamadas Lipídicas/metabolismo , Proteínas de Membrana/metabolismo , Micelas , Fosfolipídeos , Proteolipídeos , Espalhamento de Radiação , Lipossomas Unilamelares , Difração de Raios X
12.
Isotopes Environ Health Stud ; 56(5-6): 431-445, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32930001

RESUMO

Intensive groundwater use has altered the local hydrological cycle within the Bajío Guanajuatense, Mexico. To improve the knowledge of this hydrogeological system and support water management in the area, groundwater end members were identified using multivariate statistical analysis. Pumped groundwater is composed of two well-mixed end members: (a) recent recharge, affected by a reuse cycle through irrigation where nitrate and chloride evolve and reach levels of 368 mg/L and greater than 100 mg/L, respectively, and (b) deep old groundwater. Mixing estimations show that most wells extract at least 70% of deep groundwater, and some of them extract more than 94%, posing a development and groundwater sustainability conundrum in the area.


Assuntos
Deutério/análise , Monitoramento Ambiental/métodos , Água Subterrânea/análise , Isótopos de Oxigênio/análise , Abastecimento de Água/métodos , Cloretos/análise , Água Subterrânea/química , México , Nitratos/análise , Análise Espaço-Temporal , Ciclo Hidrológico , Poços de Água
13.
J Patient Rep Outcomes ; 3(1): 28, 2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31089824

RESUMO

BACKGROUND: The lack of formal instruments to measure Burden in primary caregivers of Children in a hospital context is limited because mostly of published instruments are related to cancer survivors, ambulatory environment or general context for children with chronic conditions, but none of them adapted property to prolonged hospitalization context. This leaves the rising population of hospitalized chronic children's caregivers without a proper assessment. The aim of this study was to develop a version of the Revised Impact on Family Scale adapted to primary caregivers of chronic hospitalized children. A cross-sectional study with two main stages was conducted. The first one describes the linguistic and contextual adaptation process of the instrument, and the second refers to the psychometric testing and analysis.. RESULTS: Less than 15% of the participants expressed problems with some adapted items in the scale. Eighty-six caregivers were evaluated at Josefina Martinez Hospital, mostly female (34.2 ± 11.6 years old). Majority of participants were graduated from high school, salaried employee and mothers of the chronic child. The scale exhibits a high level of internal consistency (Cronbach's alpha 0.73), excellent intra-observer reliability (Intraclass Correlation Coefficient 0.9), acceptable empirical evaluation of content validity and low and negative construct validity (Pearson's correlation coefficient - 0.23). CONCLUSIONS: This adapted version of the Revised Impact on Family Scale to the hospital context is a reliable, valid, self-administered and simple instrument to implement in order to assess the burden of primary caregivers with chronic hospitalized children.

14.
PLoS One ; 14(4): e0213667, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30995215

RESUMO

The huemul (Hippocamelus bisulcus) is an endangered cervid endemic to southern Argentina and Chile. Here we report foot lesions in 24 huemul from Bernardo O'Higgins National Park, Chile, between 2005 and 2010. Affected deer displayed variably severe clinical signs, including lameness and soft tissue swelling of the limbs proximal to the hoof or in the interdigital space, ulceration of the swollen tissues, and some developed severe proliferative tissue changes that caused various types of abnormal wear, entrapment, and/or displacement of the hooves and/or dewclaws. Animals showed signs of intense pain and reduced mobility followed by loss of body condition and recumbency, which often preceded death. The disease affected both genders and all age categories. Morbidity and mortality reached 80% and 40%, respectively. Diagnostics were restricted to a limited number of cases from which samples were available. Histology revealed severe papillomatous epidermal hyperplasia and superficial dermatitis. Electron microscopy identified viral particles consistent with viruses in the Chordopoxvirinae subfamily. The presence of parapoxvirus DNA was confirmed by a pan-poxvirus PCR assay, showing high identity (98%) with bovine papular stomatitis virus and pseudocowpoxvirus. This is the first report of foot disease in huemul deer in Chile, putatively attributed to poxvirus. Given the high morbidity and mortality observed, this virus might pose a considerable conservation threat to huemul deer in Chilean Patagonia. Moreover, this report highlights a need for improved monitoring of huemul populations and synergistic, rapid response efforts to adequately address disease events that threaten the species.


Assuntos
Conservação dos Recursos Naturais , DNA Viral/sangue , Cervos/virologia , Espécies em Perigo de Extinção , Doenças do Pé , Parapoxvirus/metabolismo , Infecções por Poxviridae , Animais , Chile , Doenças do Pé/sangue , Doenças do Pé/veterinária , Doenças do Pé/virologia , Parques Recreativos , Infecções por Poxviridae/sangue , Infecções por Poxviridae/veterinária , Infecções por Poxviridae/virologia
15.
Respir Care ; 62(12): 1533-1539, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28951468

RESUMO

BACKGROUND: Noninvasive ventilation (NIV) has proven to be useful in the management of children with acute respiratory failure as a result of acute lower respiratory infection. Despite this, evidence addressing the initiation and/or discontinuation criteria of NIV in children remains limited. The objective of this study was to evaluate the usefulness and clinical impact of an NIV protocol in hospitalized children with acute respiratory failure because of acute lower respiratory infection. METHODS: A randomized controlled clinical trial was carried out among subjects admitted during the winter season at Hospital Josefina Martinez between May and October of 2013. Inclusion criteria were age 3 months to 2 y, diagnosis of acute lower respiratory infection and requiring NIV according to a Modified Wood Scale score of ≥ 4 points. Subjects were randomized to NIV management according to medical criteria (control group) or to protocolized management of NIV (protocol group). Hours of NIV, hospital stay, and supplemental oxygen use after discontinuation of NIV, severity changes after NIV initiation, respiratory symptoms, and proportion of intubations were considered as events of interest. RESULTS: A total of 23 subjects were analyzed in the control group and 24 were analyzed in the protocol group. Hours of hospital stay, NIV, and supplemental oxygen post-NIV were not significantly different between groups (P = .70, .69, and .68, respectively). There were also no differences in intubation rate (3 of 29 for the control group and 2 of 31 for the protocol group). For the total sample there was a statistically significant decrease in the Modified Wood Scale score after 1 h of NIV (P < .001). A similar result was observed when performing a stratified intragroup analysis. CONCLUSIONS: We observed that the implementation of an NIV management protocol that integrates initiation and discontinuation criteria for NIV is feasible. However, its use showed no advantages over a non-protocolized strategy.


Assuntos
Protocolos Clínicos , Ventilação não Invasiva/métodos , Insuficiência Respiratória/terapia , Infecções Respiratórias/complicações , Doença Aguda , Criança , Feminino , Humanos , Intubação/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Masculino , Oxigenoterapia/estatística & dados numéricos , Insuficiência Respiratória/microbiologia , Resultado do Tratamento
16.
Arch Bronconeumol ; 53(3): 98-106, 2017 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-27956034

RESUMO

INTRODUCTION: Several classification systems use different criteria when assessing COPD stages. The objective of this study was to compare the prevalence and distribution of COPD stagesusing Global initiative for chronic Obstructive Lung Disease (GOLD) recommendationsand Latin American Thoracic Association (ALAT) guidelinesin a primary-care population. METHODS: Subjects attending routine primary care visits, ≥40 years of age, current or former smokers or exposed to biomass, completed a questionnaire and performed spirometry. COPD was defined as post-bronchodilator FEV1/FVC<0.70 and categorised according to GOLD-2013 criteria and ALAT-2014 guideline. The BODEx index was used to assess the prognostic value of the stratification systems. RESULTS: A total of 1743 subjects completed the interview, 1540 performed acceptable spirometry. COPD prevalence according GOLD-2013 was 20.1% and had a U-shaped stage distribution (group A: 9.3%, B: 4.3%, C: 2.0%, D: 4.6%). According to ALAT, prevalence was 19.7% with a bell-shaped stage distribution (mild: 2.9%, moderate: 9%, severe: 5.4%, very-severe: 2.7%). Approximately 73% of patients were stratified as moderate (45.4%) or severe (27.3%) by ALAT guidelines, whereas using GOLD-2013 criteria the majority of subjects (approximately 69%) were in group A (46.3%) or group B (22.7%). BODE index score increased as COPD worsened according to ALAT stratification. This is not observed with GOLD2013 criteria (similar values for B and C groups). CONCLUSIONS: Disease stages differ under ALAT and GOLD-2013 criteria. ALAT identified a greater proportion of COPD subjects in the moderate and severe categories compared with GOLD-2013, where the majority were categorised in group A. Future evaluation of the ALAT classification should address its predictive ability in terms of hospitalizations and mortality.


Assuntos
Doença Pulmonar Obstrutiva Crônica/classificação , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Índice de Gravidade de Doença
17.
ACS Cent Sci ; 6(6): 836-838, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32607430
18.
Conserv Biol ; 9(5): 1159-1168, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34261251

RESUMO

We evaluated the amounts and implications of changes in habitat connectivity on rural land-scapes by modeling the colonization success and subsequent habitat colonization of a model edge organism within real landscapes. We first inventoried the changes in the fencerow and forest-edge network of two contiguous Ohio (U.S.A.) landscapes, an agriculturally dominated till plain and a more diverse and dynamic moraine landscape, from 1940 to 1988. On the moraine the number of fencerows changed little from 1940 to 1971. The number increased by 86 during 1971-1988 as marginal farms were subdivided. The total length of fencerows on the moraine increased 2.5-fold over 48 years. On the till plain the number and total length of fencerows remained relatively constant through the study period. The sum of fencerows and forest edges was used as a measure of total ecotonal edge. On the moraine total edge increased through the study period, whereas on the till plain it decreased. We selected two levels of landscape connectivity, low and high, to model animal habitat colonization success. As connectivity increased the earliest successful colonists preempted an increasingly large proportion of the total suitable habitat, and the probability of successful colonization by later-arriving individuals decreased. The changes in connectivity that resulted from changes in both the fencerow network and the proportion of forested land have resulted in contiguous landscapes that present very different colonization potentials to organisms with long-distance dispersal capability. Given the current uncertainty of the effects of corridors on species-preservation efforts, we suggest that further modeling of this type prior to field testing will add useful insights, especially if conducted using specific species and landscape types. Las cercas, los bordes y las connotaciones de los cambios en la conectividad ilustrados por dos paisajes contiguos de Ohio.


Resumen: Evaluamos la cantidad y las connotaciones de los cambios en la conectividad del hábitat, en paisajes rurales modelando el éxito en la colonización y la subsecuente colonización del hábitat en un organismo de los bordes modelo dentro de paisajes reales. En primer lugar, inventariamos los cambios en las cercas y el sistema de bordes del bosque de dos paisajes contiguos de Ohio, una planicie de tillita dominada por agricultura y un paisaje morenico más diverso y dinámico, durante 1940-1988. En la morena el número de cercas cambió poco entre 1940-1971. El número se incrementó en 86 durante 1971-1988, a medida que las granjas marginales fueron subdivididas. La extensión total de las cercas en la morena se multiplicó 2.5 veces durante un período de 48 años. En la planicie de tillita el número y la extensión total de las cercas permaneció relativamente constante a través del período de estudio. La suma de las cercas y el borde del bosque fue utilizado como medida del borde total del ecotono. En la morena el borde total se incrementó durante el período de estudio, mientras que en la planicie de tillita decreció. Seleccionamos dos niveles de conectividad del paisaje, bajo y alto, para modelar el suceso de la colonizacion del hábitat animal. En la medida en que la conectividad se incrementó, los colonizadores tempranos más exitosos se apropiaron de una gran proporción del hábitat total disponible y la probabilidad del éxito en la colonización de los individuos que fueron llegando más tarde decreció. Los cambios en conectividad que resultaron de los cambios en el conjunto de las cercas y la proporción de la tierra forestada, ha resultado en paisajes contiguous que presentan potenciales de colonización muy diferentes para los organismos con una capacidad de dispersión a gran distancia. Dada la incertidumbre actual sobre los efectos de los corredores sobre los esfuerzos de preservación de las especies, sugerimos que la intesificación en este tipo de modelado antes de ser probando en el campo puede adicionar información útil, especialmente si se conduce utilizando especies y tipos de paisajes específicos.

19.
Rev. méd. Chile ; 147(1): 47-52, 2019. tab
Artigo em Espanhol | LILACS | ID: biblio-991372

RESUMO

Background: Cardiovascular complications can occur in up to 80% of adolescent patients with eating disorders (ED) and account for 30% of their mortality. Aim: To evaluate cardiovascular complications in adolescents with ED and their evolution after refeeding. Patients and Methods: In adolescents with ED admitted to treatment, we assessed the nutritional status, weight loss prior to consultation, presence of bradycardia (BC, defined as heart rate < 60 bpm), we performed an electrocardiogram (ECG) and an echocardiography and measured thyroid hormones. Results: We studied 53 women aged 16.4 ± 2.3 years. Fifteen had a diagnosis of Anorexia Nervosa (AN), seven of Bulimia (BN), eight a not otherwise specified ED (ED-NOS), four a Binge Eating Disorder (BED), sixteen an Atypical Anorexia (AAN) and three an Atypical Bulimia (ABN). Thirty four percent were malnourished and 3.8% overweight. The most common cardiac problem was BC in 51%. In eight of 26 patients in whom an echocardiogram was done, it was abnormal. Six had a decreased ventricular mass, three a pericardial effusion and three valvular involvement. There was a significant association between bradycardia and malnutrition, weight loss and low free triiodothyronine levels. BC was significantly more common in patients with AN, but it also occurred in half of the patients with AAN and in one of three patients with other types of ED. At follow up, bradycardia significantly improved with refeeding. Conclusions: There is an association between all types of ED and bradycardia, as well as anatomical and functional cardiac anomalies.


Assuntos
Humanos , Feminino , Criança , Adolescente , Adulto Jovem , Bradicardia/etiologia , Transtornos da Alimentação e da Ingestão de Alimentos/complicações , Bradicardia/fisiopatologia , Ecocardiografia , Redução de Peso/fisiologia , Transtornos da Alimentação e da Ingestão de Alimentos/fisiopatologia , Índice de Massa Corporal , Fatores de Risco , Análise de Variância , Estudos de Coortes , Estatísticas não Paramétricas , Desnutrição/complicações , Desnutrição/fisiopatologia , Eletrocardiografia
20.
Diagn Pathol ; 7: 87, 2012 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-22818553

RESUMO

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a disorder associated to cigarette smoke and lung cancer (LC). Since epigenetic changes in oncogenes and tumor suppressor genes (TSGs) are clearly important in the development of LC. In this study, we hypothesize that tobacco smokers are susceptible for methylation in the promoter region of TSGs in airway epithelial cells when compared with non-smoker subjects. The purpose of this study was to investigate the usefulness of detection of genes promoter methylation in sputum specimens, as a complementary tool to identify LC biomarkers among smokers with early COPD. METHODS: We determined the amount of DNA in induced sputum from patients with COPD (n = 23), LC (n = 26), as well as in healthy subjects (CTR) (n = 33), using a commercial kit for DNA purification, followed by absorbance measurement at 260 nm. The frequency of CDKN2A, CDH1 and MGMT promoter methylation in the same groups was determined by methylation-specific polymerase chain reaction (MSP). The Fisher's exact test was employed to compare frequency of results between different groups. RESULTS: DNA concentration was 7.4 and 5.8 times higher in LC and COPD compared to the (CTR) (p < 0.0001), respectively. Methylation status of CDKN2A and MGMT was significantly higher in COPD and LC patients compared with CTR group (p < 0.0001). Frequency of CDH1 methylation only showed a statistically significant difference between LC patients and CTR group (p < 0.05). CONCLUSIONS: We provide evidence that aberrant methylation of TSGs in samples of induced sputum is a useful tool for early diagnostic of lung diseases (LC and COPD) in smoker subjects. VIRTUAL SLIDES: The abstract MUST finish with the following text: Virtual Slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1127865005664160.


Assuntos
DNA/análise , Detecção Precoce de Câncer/métodos , Genes Supressores de Tumor , Neoplasias Pulmonares/diagnóstico , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Escarro/química , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Metilação de DNA/genética , Humanos , Neoplasias Pulmonares/genética , Pessoa de Meia-Idade , Regiões Promotoras Genéticas/genética , Doença Pulmonar Obstrutiva Crônica/genética , Fumar/efeitos adversos , Adulto Jovem
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