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1.
Heliyon ; 9(4): e15367, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37101642

RESUMO

Model organisms are fundamental in cancer research given that they rise the possibility to characterize in a quantitative-objective fashion the organisms as a whole in ways that are infeasible in humans. From this perspective, model organisms with short generation times and established protocols for genetic manipulation allow the understanding of basic biology principles that might guide carcinogenic onset. The cancer-hallmarks (CHs) approach, a modular perspective for cancer understanding, stands that underlying the variability among different cancer types, critical events support the carcinogenic origin and progression. Thus, CHs as interconnected genetic circuitry, have a causal effect over cancer biogenesis and might represent a comparison scaffold among model organisms to identify and characterize evolutionarily conserved modules to understand cancer. Nevertheless, the identification of novel cancer regulators by comparative genomics approaches relies on selecting specific biological processes or related signaling cascades that limit the type of detected regulators, even more, holistic analysis from a systemic perspective is absent. Similarly, although the plant Arabidopsis thaliana has been used as a model organism to dissect specific disease-associated mechanisms, given the evolutionary distance between plants and humans, a general concern about the utility of using A. thaliana as a cancer model persists. In the present research, we take advantage of the CHs paradigm as a framework to establish a functional systemic comparison between plants and humans, that allowed the identification not only of specific novel key genetic regulators, but also, biological processes, metabolic systems, and genetic modules that might contribute to the neoplastic transformation. We propose five cancer-hallmarks that overlapped in conserved mechanisms and processes between Arabidopsis and human and thus, represent mechanisms which study can be prioritized in A. thaliana as an alternative model for cancer research. Additionally, derived from network analyses and machine learning strategies, a new set of potential candidate genes that might contribute to neoplastic transformation is described. These findings postulate A. thaliana as a suitable model to dissect, not all, but specific cancer properties, highlighting the importance of using alternative complementary models to understand carcinogenesis.

2.
Iran J Parasitol ; 15(3): 315-320, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33082795

RESUMO

BACKGROUND: The environmental contamination with Toxocara canis eggs increases the risk of dissemination and transmission of the parasite in dogs and paratenic hosts such as humans. We aimed to evaluate different disinfectants to compare their effect on T. canis eggs. METHODS: For its realization, 850 embryonated eggs were obtained, which were suspended in a solution of 5% formaldehyde and distilled water in Eppendorf tubes. In the tubes containing the 850 embryonated eggs, researchers was added 0.5 mL of each solution (enzymatic solution, sodium hypochlorite, iodopovidone, quaternary of ammonium, benzalkonium chloride, and super oxidation solution). After mixing, an aliquot was taken, observed under the microscope, and the number of broken eggs counted at different times to find the most effective ovicidal moment. RESULTS: The enzymatic disinfectant present a significant difference (P = 0.05) with 276.06 broken eggs followed by ammonium with 105.20 broken eggs. After 10 min, the ammonium solution was the one that showed a significant difference of 50.50 hatched eggs, followed by the enzymatic 26.80 and hypochlorite 25.00 treatments. After 20 min, the enzymatic solution treatment showed a significant difference with the other solutions showing an increase of 98.80 broken eggs. In the 30 and 40-min times, only the enzymatic treatment showed a significant difference of 334.10 and 381.70 of broken eggs respectively. CONCLUSION: The enzymatic solution has the greatest ovicidal effect against the eggs of T. canis to present a greater number of broken eggs in a given time between 20 and 40 minutes.

3.
PLoS One ; 15(5): e0233528, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32437468

RESUMO

BACKGROUND & AIM: Worldwide, measures are being implemented to eradicate hepatitis B (HBV) and C (HCV) viruses, which can be transmitted from the mother during childbirth. This study aims to determine the prevalence of HBV and HCV in pregnant women in Spain, focusing on country of origin, epidemiological factors and risk of vertical transmission (VT). METHODOLOGY: Multicentre open-cohort study performed during 2015. HBV prevalence was determined in 21870 pregnant women and HCV prevalence in 7659 pregnant women. Epidemiological and risk factors for VT were analysed in positive women and differences between HBV and HCV cases were studied. RESULTS: HBV prevalence was 0.42% (91/21870) and HCV prevalence was 0.26% (20/7659). Of the women with HBV, 65.7% (44/67) were migrants. The HBV transmission route to the mother was unknown in 40.3% of cases (27/67) and VT in 31.3% (21/67). Among risk factors for VT, 67.7% (42/62) of the women had viraemia and 14.5% (9/62) tested HBeAg-positive. All of the neonates born to HBV-positive mothers received immunoprophylaxis, and none contracted infection by VT. In 80% (16/20) of the women with HCV, the transmission route was parenteral, and nine were intravenous drug users. Viraemia was present in 40% (8/20) of the women and 10% (2/20) were HIV-coinfected. No children were infected. Women with HCV were less likely than women with HBV to breastfeed their child (65% vs. 86%). CONCLUSIONS: The prevalences obtained in our study of pregnant women are lower than those previously documented for the general population. Among the women with HBV, the majority were migrants and had a maternal family history of infection, while among those with HCV, the most common factor was intravenous drug use. Despite the risk factors observed for VT, none of the children were infected. Proper immunoprophylaxis is essential to prevent VT in children born to HBV-positive women.


Assuntos
Hepatite B/epidemiologia , Hepatite C/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Estudos de Coortes , Feminino , Hepacivirus/isolamento & purificação , Hepatite B/transmissão , Vírus da Hepatite B/isolamento & purificação , Hepatite C/transmissão , Humanos , Transmissão Vertical de Doenças Infecciosas , Gravidez , Fatores de Risco , Estudos Soroepidemiológicos , Espanha
4.
Artigo em Inglês | MEDLINE | ID: mdl-31083523

RESUMO

This work studies the health status of two populations similar in most social and environmental interactions but one: the individuals from one population are victims of an internal armed conflict. Both populations are located in the Risaralda province, Colombia and the data for this study results from a combination of administrative records from the health system, between 2011 and 2016. We implemented a methodology based on graph theory that defines the system as a set of heterogeneous social actors, including individuals as well as organizations, embedded in a biological environment. The model of analysis uses the diagnoses in medical records to detect morbidity and mortality patterns for each individual (ego-networks), and assumes that these patterns contain relevant information about the effects of the actions of social actors, in a given environment, on the status of health. The analysis of the diagnoses and causes of specific mortality, following the Social Network Analysis framework, shows similar morbidity and mortality rates for both populations. However, the diagnoses' patterns show that victims portray broader interactions between diagnoses, including mental and behavioral disorders, due to the hardships of this population.


Assuntos
Conflitos Armados/psicologia , Conflito Psicológico , Nível de Saúde , Transtornos Mentais/epidemiologia , Transtornos Mentais/mortalidade , Morbidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Colômbia/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
6.
Vet World ; 10(7): 798-802, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28831225

RESUMO

AIM: The aim of the study was to identify the presence of eggs of Toxocaraspp. in dog hair and to identify any risk factors associated with this. MATERIALS AND METHODS: A total of 96 dogs were sampled collecting hair from the head, perianal and hindquarters. Epidemiologic data from each animal were recorded to identify risk factors. The samples of hair were washed with solutions of distilled water, phosphate-buffered saline and Tween 20 detergent. Microscopic analysis was subsequently performed for the identification of eggs. RESULTS: Out of the total dogs, 41.7% were positive for the presence of parasite egg in their hair. Toxocara eggs were found in hair from the head (14.5%), tail (20.8%), and limbs (10.4%). Dogs, younger than 12 months old, showed higher values (4.7%) of egg presence in the perianal area (p<0.05). The principal risk factors for the presence of eggs in hair were not deworming (odds ratio [OR]=3.60, p<0.004) and not brushing (OR=2.26, p<0.12). CONCLUSION: These results show that in the state of Mexico there is a high percentage of dogs contaminated with Toxocara spp. eggs in their hair. This should be seriously considered due to the potential problems of toxocariasis and the risk to public health.

7.
Vet Dermatol ; 28(6): 622-e152, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28691193

RESUMO

BACKGROUND: African pygmy hedgehogs (Atelerix albiventris) are popular pets belonging to the Erinaceidae family of spined mammals. Amongst the most common skin diseases occurring in this species is infestation caused by the mite Caparinia spp. Due to their skin anatomy and spiny coat, detection of skin lesions in these hedgehogs can be difficult. This may result in delays in seeking medical care, which may lead to secondary bacterial infection and self-inflicted trauma. Multiple therapies have been used in the treatment of this skin condition including ivermectin, amitraz, fipronil and selamectin. A drug which could be administered as a single oral dose would be advantageous to these pets and their owners. OBJECTIVE: To evaluate the effect of a single oral dose (15 mg/kg) of fluralaner on Caparinia tripilis infestation in the African pygmy hedgehog. ANIMALS: A 10-month-old African pygmy hedgehog weighing 184 g. METHODS: Response to treatment was monitored by dermatological examination and superficial skin scrapings repeated at 7, 14, 21, 30, 60, 90 and 120 days following fluralaner administration. RESULTS: On Day 7 after treatment, adult mites were observed exhibiting normal movement. On Day 14, only dead mites were observed. No life stages of the mites were found after Day 21. CONCLUSION AND CLINICAL IMPORTANCE: A single oral dose at 15 mg/kg of fluralaner was effective within 21 days after treatment for capariniasis in this case. Further studies are required to evaluate the drug's safety and toxicology in hedgehogs, and to confirm efficacy.


Assuntos
Acaricidas/uso terapêutico , Ouriços/parasitologia , Isoxazóis/uso terapêutico , Infestações por Ácaros/veterinária , Psoroptidae/efeitos dos fármacos , Acaricidas/administração & dosagem , Administração Oral , Animais , Isoxazóis/administração & dosagem , Masculino , Infestações por Ácaros/diagnóstico , Infestações por Ácaros/tratamento farmacológico
8.
Vet Dermatol ; 28(4): 393-e91, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28251698

RESUMO

BACKGROUND: Psoroptes cuniculi, a nonburrowing ear mite, is a common ectoparasite of rabbits. Constant irritation of the auditory canal by the presence of this mite can lead to otitis externa or otoacariasis. OBJECTIVE: The goal of this study was to evaluate the effect of fluralaner on rabbits naturally infested with P. cuniculi and exhibiting clinical signs. ANIMALS: Fifteen female New Zealand domestic rabbits with otitis due to naturally occurring infestation with P. cuniculi. METHODS: The external ears and ear canals of each individual were examined; samples of otic exudate were extracted with cotton swabs and examined microscopically for identification of the ectoparasite. Each animal was treated with a single 25 mg/kg oral dose of fluralaner. The amount of otic exudate/cerumen was assessed and samples were obtained from the ears to evaluate for presence or absence of mites at 4, 8, 12, 16, 20, 40 and 90 days after receiving treatment. RESULTS: Post-treatment, the amount of otic exudate decreased rapidly in all animals; by Day 12 and until the end of the study all rabbits were judged to have low amount of exudate with normally visible canals. The percentage of ears positive for P. cuniculi decreased to 13.3% of ears sampled by Day 4, and by Day 12 all rabbits were negative for the parasite. CONCLUSION: Administration of a single oral dose of fluralaner was effective for the treatment of naturally occurring P. cuniculi infestation in rabbits during a 90 day period.


Assuntos
Acaricidas/uso terapêutico , Otopatias/veterinária , Isoxazóis/uso terapêutico , Infestações por Ácaros/veterinária , Psoroptidae , Coelhos/parasitologia , Acaricidas/administração & dosagem , Administração Oral , Animais , Otopatias/tratamento farmacológico , Otopatias/parasitologia , Feminino , Isoxazóis/administração & dosagem , Infestações por Ácaros/tratamento farmacológico
9.
Vet World ; 9(11): 1233-1237, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27956774

RESUMO

AIM: Intestinal parasites are one of the most common problems in sheep production systems. However, the strategies used to eliminate these parasites have not yielded satisfactory results. Therefore, the aim of this study was to determine the effect of five anthelmintics (with different active ingredients) on the parasite load in sheep. MATERIALS AND METHODS: In this study, 107 Rambouillet breed sheep were randomly assigned to five groups. Next, fecal samples were taken directly from the rectum and sent to the laboratory for analysis. We then dewormed each group of sheep using different anthelmintic products: Ivermectin 1%/clorsulon 10%, levamisole 12%, closantel sodium 5%, ivermectin 10%, and closantel 5%/albendazole 3.75% with a dosage corresponding to each sheep. At 15 days post-treatment, we took fecal samples and performed a coproparasitoscopic study, using the Faust flotation technique to assess the presence or absence of parasite eggs and the McMaster technique to quantify eggs. RESULTS: Ivermectin/clorsulon was more effective in eliminating parasites than other anthelmintics used, especially in Haemonchus spp. CONCLUSION: The results of this study indicate that using ivermectin/clorsulon decreases the number of eggs in feces and is one alternative in controlling parasites in sheep, leading to a reduction in the incidence of health problems, and consequently, improved productivity.

10.
Vet Dermatol ; 27(5): 353-e88, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27511592

RESUMO

BACKGROUND: There are few licensed options for the treatment of canine sarcoptic mange. OBJECTIVE: To evaluate the efficacy of fluralaner in dogs with sarcoptic mange infestation. ANIMALS: Seventeen dogs with a diagnosis of Sarcoptes scabiei based on positive skin scrapings. METHODS: A single dose of oral fluralaner was administered according to the manufacturer's instructions. Assessments of pruritus and lesions were performed every 7 days for 1 month. RESULTS: By Day 14 post-treatment, skin scrapings from all dogs were negative for mites. At the beginning of the study there was a negative correlation between body weight of the subject and pruritus [Pearson correlation coefficient (PCC) = -0.396, P = 0.007] and a positive correlation between pruritus and lesion severity (PCC 0.755, P = 0.0001). Significant decreases in lesion size and pruritus were observed within the first 14-21 days, respectively, and improvement in these parameters continued until the end of the study at Day 28. CONCLUSION: Fluralaner was effective in eliminating scabies mites within 14 days and significantly resolved the clinical signs associated with sarcoptic mange within 21 days after a single dose.


Assuntos
Doenças do Cão/parasitologia , Inseticidas/uso terapêutico , Isoxazóis/uso terapêutico , Escabiose/veterinária , Animais , Doenças do Cão/tratamento farmacológico , Cães , Feminino , Masculino , Escabiose/tratamento farmacológico
11.
Acta biol. colomb ; 19(3): 381-391, Sept.-Dec. 2014. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-724867

RESUMO

El uso de productos extraídos o provenientes de la fauna silvestre es relevante para el desarrollo económico y el bienestar social en muchos lugares del mundo. Sin embargo, frecuentemente la fauna silvestre entra en los circuitos de tráfico ilegal para abastecer los mercados de mascotas y productos como pieles, plumas, "carne de monte", entre otros. El tráfico ilegal genera enormes presiones sobre las especies sujetas a extracción y es una de las principales amenazas para estas. En Colombia, el tráfico de tortugas es de importancia debido a los volúmenes explotados y al significado que tienen sus productos para las comunidades. Mediante el Análisis de Redes se caracterizó espacialmente, a nivel de Departamento, el tráfico de los cinco géneros de testudíneos continentales de Colombia más traficados (Trachemys, Chelonoidis, Kinosternon, Podocnemis y Rhinoclemmys), tomando como base los registros de incautación y decomiso recopilados por el Ministerio de Ambiente y Desarrollo Sostenible entre los años 2005 y 2009. Se encontró que la red de tráfico ilegal de testudíneos está articulada con mercados internacionales y propende por abastecer mercados del interior del país (región Andina), siendo los Departamentos de las costas Caribe y Pacífica, y de la Orinoquía, los principales extractores de especímenes. Se identificaron los Departamentos de Quindío, Santander, Antioquia y Putumayo como intermediarios y consumidores. Finalmente, se proponen medidas socioculturales y coercitivas como mecanismos de desarticulación de las redes de tráfico ilegal, siendo dichas acciones un soporte para la conservación y el uso sostenible de los recursos naturales.


The use of wildlife is important for supporting the economic and demographic growth in emerging countries. Nevertheless, the products of wildlife usually come from illegal trade to supply fur, wild meat and pet markets. Illegal trade puts great pressure over wild populations and threats some endangered species. In Colombia, the trade of wildlife is important because of the volumes traded and the cultural and economic connotation of some products. We describe the spatial structure of illegal trade of wildlife at departmental level for the five most traded genera of Colombian tortoises (Trachemys, Chelonoidis, Kinosternon, Podocnemis and Rhinoclemmys). This study is based on the reports of seizures between 2005 and 2009 compiled by the Ministerio de Medio Ambiente y Desarrollo of Colombia. We apply Network Analysis to study and evidence that the illegal trade network of tortoises includes international markets and supplies the Andean region. The Caribbean, Pacific and Orinoquia regions are the principal suppliers. Quindio, Santander, Antioquia and Putumayo are the biggest jobbers and consumers of wild tortoises. We propose sociocultural and cohercitive actions to fragment the trade network and their illegal market as well as promoting the conservation and sustainable use of tortoises.

12.
PLoS One ; 6(10): e26784, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22039550

RESUMO

Conservation strategies for long-lived vertebrates require accurate estimates of parameters relative to the populations' size, numbers of non-breeding individuals (the "cryptic" fraction of the population) and the age structure. Frequently, visual survey techniques are used to make these estimates but the accuracy of these approaches is questionable, mainly because of the existence of numerous potential biases. Here we compare data on population trends and age structure in a bearded vulture (Gypaetus barbatus) population from visual surveys performed at supplementary feeding stations with data derived from population matrix-modelling approximations. Our results suggest that visual surveys overestimate the number of immature (<2 years old) birds, whereas subadults (3-5 y.o.) and adults (>6 y.o.) were underestimated in comparison with the predictions of a population model using a stable-age distribution. In addition, we found that visual surveys did not provide conclusive information on true variations in the size of the focal population. Our results suggest that although long-term studies (i.e. population matrix modelling based on capture-recapture procedures) are a more time-consuming method, they provide more reliable and robust estimates of population parameters needed in designing and applying conservation strategies. The findings shown here are likely transferable to the management and conservation of other long-lived vertebrate populations that share similar life-history traits and ecological requirements.


Assuntos
Aves , Espécies em Perigo de Extinção , Modelos Teóricos , Animais , Coleta de Dados
13.
PLoS One ; 3(12): e4084, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19115009

RESUMO

BACKGROUND: Human-predator conflicts are directly or indirectly threatening many species with extinction. Thus, biologists are urged to find simple solutions to complex situations while avoiding unforeseen conservation outcomes. The provision of supplementary food at artificial feeding sites (AFS) is frequently used in the conservation of scavenger bird populations currently suffering from indirect poisoning, although no scientific studies on its effectiveness have been conducted. METHODOLOGY/PRINCIPAL FINDINGS: We used a long-term data set of 95 individually marked birds from the largest European core of the endangered bearded vulture (Gypaetus barbatus) to test the long-term effects of specific AFS for bearded vultures on their survival rates (by CMR models) and population dynamics (by Monte Carlo simulations) in an area where fatalities derived from illegal poisoning and the use of other toxics like veterinary drugs have increased over the last several years. Our data support the positive relationship between the use of AFS and survival. However, contrary to theoretical predictions (e.g. high and more stable adult survival among long-lived species), the use of AFS increased only survival of pre-adults. Moreover, AFS buffered the effects of illegal poisoning on this age-class, while adult survival decreased over years. Our simulations predicted a maximum value of extinction probability over a time horizon of 50 years. Population projections run with survival rates expected in scenarios without poisoning predicted the situation of least conservation concern, while including only AFS can maintain a large floater surplus that may delay population decline but fails to reduce poisoning risk among adults. CONCLUSIONS/SIGNIFICANCE: Although AFS are not effective to save bearded vultures from an expected population decline, they delay population extinction and can be a useful tool for prolonging population viability while combating illegal and indirect poisoning. The eradication of different sources of poisoning is of top priority to ensure the long-term viability of this and many other species.


Assuntos
Extinção Biológica , Falconiformes/fisiologia , Animais , Conservação dos Recursos Naturais , Método de Monte Carlo , Densidade Demográfica , Dinâmica Populacional
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