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1.
Braz J Med Biol Res ; 56: e12693, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37255095

RESUMEN

Leishmaniasis is a neglected disease that affects millions of people worldwide, and special attention should be given to treatment because the available drugs have limitations, which can lead to low therapeutic adherence and parasitic resistance. This study evaluated the activity of the bioactive naphthoquinones, lapachol and ß-lapachone, against Leishmania amazonensis. The cell alterations were evaluated in vitro on promastigote and amastigote forms. The lethal dose (LD50) at 24, 48, and 72 h on the promastigote's forms using lapachol was 75.60, 72.82, and 58.85 µg/mL and for ß-lapachone was 0.65, 1.24, and 0.71 µg/mL, respectively. The naphthoquinones significantly inhibited the survival rate of L. amazonensis amastigotes at 83.11, 57.59, and 34.95% for lapachol (82.28, 41.14, and 20.57 µg/mL), and 78.49, 83.25, and 80.22% for ß-lapachone (3.26, 1.63, and 0.815 µg/mL). The compounds on the promastigote's forms led to the loss of mitochondrial membrane potential, induced changes in the integrity of the membrane, caused damage to cells suggestive of the apoptotic process, and showed inhibition of tumor necrosis factor (TNF)-α and interleukin (IL)-6 production. The results showed that these naphthoquinones are promising candidates for research on new drugs with anti-Leishmania activity derived from natural products.


Asunto(s)
Antiprotozoarios , Leishmania mexicana , Naftoquinonas , Humanos , Animales , Ratones , Antiprotozoarios/farmacología , Antiprotozoarios/uso terapéutico , Ratones Endogámicos BALB C , Naftoquinonas/farmacología
2.
Braz. j. med. biol. res ; 56: e12693, 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1439700

RESUMEN

Leishmaniasis is a neglected disease that affects millions of people worldwide, and special attention should be given to treatment because the available drugs have limitations, which can lead to low therapeutic adherence and parasitic resistance. This study evaluated the activity of the bioactive naphthoquinones, lapachol and β-lapachone, against Leishmania amazonensis. The cell alterations were evaluated in vitro on promastigote and amastigote forms. The lethal dose (LD50) at 24, 48, and 72 h on the promastigote's forms using lapachol was 75.60, 72.82, and 58.85 μg/mL and for β-lapachone was 0.65, 1.24, and 0.71 μg/mL, respectively. The naphthoquinones significantly inhibited the survival rate of L. amazonensis amastigotes at 83.11, 57.59, and 34.95% for lapachol (82.28, 41.14, and 20.57 µg/mL), and 78.49, 83.25, and 80.22% for β-lapachone (3.26, 1.63, and 0.815 µg/mL). The compounds on the promastigote's forms led to the loss of mitochondrial membrane potential, induced changes in the integrity of the membrane, caused damage to cells suggestive of the apoptotic process, and showed inhibition of tumor necrosis factor (TNF)-α and interleukin (IL)-6 production. The results showed that these naphthoquinones are promising candidates for research on new drugs with anti-Leishmania activity derived from natural products.

3.
Lett Appl Microbiol ; 75(5): 1383-1388, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35971818

RESUMEN

The objective of this study is to verify in vitro susceptibility of Pythium insidiosum against the agricultural fungicides mefenoxam and pyraclostrobin and evaluate the toxicity of both compounds. Twenty-one P. insidiosum isolates were tested against mefenoxam and pyraclostrobin using the broth microdilution method. Minimum inhibitory and oomicidal concentrations for both compounds were established. Additionally, scanning electron microscopy was performed on P. insidiosum hyphae treated with the sublethal concentration of each fungicide. The toxicity of the compounds was evaluated in vivo Caenorhabditis elegans model. The concentration to inhibit 100% of P. insidiosum growth ranged from 0·625 to 10 µg ml-1 for mefenoxam and from 0·019 to 5 µg ml-1 for pyraclostrobin. The SEM analysis revealed changes on the surface of the hyphae treated with the fungicides, suggesting possible damage caused by these compounds. There was no evidence of toxicity in vivo models. Mefenoxam and pyraclostrobin did not show toxicity at the doses evaluated and have inhibitory effects on the pathogenic oomycete P. insidiosum. However, further evaluations of their pharmacokinetics and toxicity in different animal species and possible pharmacological interactions are necessary to infer a possible use in the clinical management of pythiosis.


Asunto(s)
Fungicidas Industriales , Pythium , Animales , Fungicidas Industriales/farmacología , Pruebas de Sensibilidad Microbiana
4.
Encephale ; 46(5): 364-371, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32576365

RESUMEN

INTRODUCTION: Migrants and refugees often face potentially traumatic events and post-migratory stressors. Upon arrival in the host country, they can be referred to mental health services to assess the impact of their previous experiences. These cross-cultural clinical encounters may raise questions, particularly regarding the assessment of mental health using models based on Western conceptions of psychopathology. OBJECTIVES AND METHOD: The objective of the present non-systematic review of the literature is to discuss the psychological evaluation of post-traumatic reactions in migrants and refugees. More specifically, we present current research on psychopathology, resilience and post-traumatic development (PTG) among the migrant and refugee population. We also examine the cross-cultural validity of concepts such as Post-Traumatic Stress Disorder, resilience and PTG. Finally, we describe the most frequently used tools in cross-cultural psychological assessment and briefly reflect on the question of cultural sensitivity of mental health professionals. A bibliographic search was carried out using the databases: PILOTS, Pubmed, APA PsycNET, and Google Scholar using the following keywords: "migrants", "refugees", "posttraumatic stress disorder", "mental health", "Psychopathology", "risk factors", "protection factors", "posttraumatic growth" and "resilience". We have also reviewed the reference lists of articles encountered from database searches. RESULTS: Responses to a potentially traumatic situation are multiple. Regarding the migrant and refugee population, the reviewed articles studied different post-traumatic reactions such as resilience, post-traumatic development, and psychopathologies. The most studied psychopathological responses were depression, anxiety and Post-traumatic Stress Disorder. After reviewing these studies, we asked the following question: considering the complexity of the migration process, what are the factors associated with the development of these different post-traumatic responses? Indeed, several individual and social factors before, during and after migration influence the mental health of individuals in a migration situation. Among the most cited risk factors identified were: to be a victim of or witness to violence in the country of origin and, after migration, to face post-migration difficulties such as asylum denial, to be in a precarious situation with regard to housing and work, as well as the difficulties linked to adaptation to the new culture. We have also described protective factors for the mental health of this population, such as: social support, psychological support, and a good quality of life in the host country. The reviewed articles also describe an important influence of cultural aspects on mental health, such as the perception of an event as traumatic. Although the authors of the reviewed articles accept this influence of culture on post-traumatic responses, most of the tools used to assess the mental health of migrants and refugees were created in a Western context. Studies show a growing concern with these cultural aspects, and certain tools that allow a more culturally sensitive evaluation, such as the "Cultural Formulation Interview", are being developed. DISCUSSION AND CONCLUSION: Even if the concern with the sensitivity of the tools used in cross-cultural assessment seems to be more present in the international literature, researchers seem to encounter difficulties in better understanding the effects of culture on the mental health of individuals. With increasingly diverse societies, new research should not be based on participants' geographic or ethnic origins, but rather try to "unpack" culture with, for example, the exploration of the relationships between certain values or orientations and the different expressions of psychological distress. Finally, given the still lacking development in the field of cross-cultural research, certain practices, such as the participation of interpreters, the supervision of cultural mediators or the use of culturally sensitive tools, can help the clinician to maintain good practices with patients from different cultures in the diagnostic and psychotherapeutical processes.


Asunto(s)
Refugiados , Trastornos por Estrés Postraumático , Trastornos de Ansiedad , Humanos , Salud Mental , Calidad de Vida , Trastornos por Estrés Postraumático/diagnóstico , Trastornos por Estrés Postraumático/epidemiología
5.
Pathologica ; 111(2): 62-66, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31388197

RESUMEN

INTRODUCTION: There is a need for the development of new biomarkers for diagnosis and prognosis of ovarian cancer, which can ideally serve as targets for new therapeutic modalities and individualization of treatment. The objectives of this study were to determine the prognostic significance of the neutrophil/lymphocyte ratio in the peripheral blood of patients with ovarian cancer and tumor staging, and to associate this marker with the immune expression of a panel of cytokines. METHODS: The study included 24 patients with malignant ovarian neoplasia treated at the Pelvic Mass Outpatient Clinic of the Clinical Hospital of the Federal University of Triângulo Mineiro. The neutrophil/lymphocyte ratio was calculated as the absolute number of neutrophils divided by the absolute number of lymphocytes. Expression of the cytokines was evaluated by the immunohistochemistry method (IL2, IL5, IL6, IL8, IL10 and TNF-R1). Fisher's statistical test was used for the comparisons of immunohistochemical expression with the neutrophil/lymphocyte ratio, and the unpaired T-Test was used in the analysis of the association of this ratio with tumor staging. RESULTS: A neutrophil/lymphocyte ratio > 2.6 was significantly higher in the more advanced stages (II-IV) of malignant ovarian neoplasia (p = 0.0098). In addition, this ratio > 2.6 was associated with IL2 stromal immunostaining (1-3) (p = 0.0472). CONCLUSION: Stromal IL-2 is associated with higher a neutrophil/lymphocyte ratio, suggesting a worse prognosis in ovarian cancer and its role in tumor immunology; a neutrophil/lymphocyte ratio > 2.6 is associated with more advanced stages of malignant ovarian neoplasia.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma Epitelial de Ovario/metabolismo , Interleucina-2/metabolismo , Linfocitos/metabolismo , Neutrófilos/metabolismo , Neoplasias Ováricas/metabolismo , Adulto , Carcinoma Epitelial de Ovario/diagnóstico , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Ováricas/diagnóstico , Estudios Prospectivos , Células del Estroma/metabolismo , Células del Estroma/patología
6.
Arq. bras. med. vet. zootec. (Online) ; 71(3): 791-796, May-June 2019. tab, ilus
Artículo en Inglés | VETINDEX, LILACS | ID: biblio-1011303

RESUMEN

In this essay, we quantify the concentration of collagen fibers in broiler chickens exposed to increasing concentrations of cupuacu seed by-product. Collection of material was carried out in five chickens per treatment at 70 days old in the groups: control, 5% and 10% inclusion of cupuacu seed by-product. Fragments of Thoracic Pectoralis (PT) and Iliotibial lateralis (ITL) muscles were prepared for light and electronic microscopy. The amount of collagen fibers in the muscle groups was 1.08±0.61% in the PTC group; 6.24±2.58% in PT5% and 7.30±2.75% in PT10%. In the Iliotibial Lateralis groups, the results were 6.96±3.14% in the ITLC; 7.43±4.22% in the ITL5% and 8.66±2.35% in ITL10%. The amount of collagen fibers in the ITL5% and ITL10% groups showed no significant statistical difference. However, when compared to the ILTC group, there was a significant statistical difference. The PT muscle responds to standard nutritional changes, unlike the ILT muscle, which requires a high-nutrient formulation. The use of 5% cupuacu seed by-product has proven to be a viable alternative source of animal feed, as it promotes an increase in the concentrations of collagen fibers in the musculature of broiler chickens and is possibly the determining factor in meat texture.(AU)


Neste estudo, foram quantificadas as concentrações de fibras colágenas de frangos expostos a crescentes concentrações de farinha de cupuaçu. A coleta de material foi realizada em cinco animais por tratamento, aos 70 dias de idade, nos grupos: controle, inclusão de 5% e de 10% de farinha de cupuaçu. Fragmentos dos músculos peitoral torácico (PT) e iliotibial lateral (ITL) foram preparados para microscopia de luz e eletrônica. A quantidade de fibras colágenas nos grupos foi: 1,08±0,61% no grupo PTC; 6,24±2,58% em PT5% e 7,30±2,75% em PT10%. Nos grupos iliotibial lateral, os resultados foram: 6,96±3,14% no ITLC; 7,43±4,22% no ITL5% e 8,66±2,35% em ITL10%. A quantidade de fibras colágenas nos grupos ITL5% e ITL10% não apresentou diferença estatística significativa. No entanto, quando comparados ao grupo ILTC, houve diferença estatística significativa. O músculo PT responde a mudanças nutricionais padrão, ao contrário do músculo ILT, que requer alta formulação nutricional. O uso de 5% de farinha de cupuaçu provou ser uma fonte alternativa viável de alimentação animal, pois promove um aumento nas concentrações de fibras de colágeno na musculatura de frangos de corte e é possivelmente um fator determinante na textura da carne.(AU)


Asunto(s)
Animales , Colágeno/agonistas , Procolágeno/agonistas , Dieta/veterinaria , Alimentación Animal , Carne/análisis , Pollos
7.
Arq. bras. med. vet. zootec. (Online) ; 71(1): 349-352, jan.-fev. 2019. ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1038585

RESUMEN

Este estudo objetiva reportar a ocorrência de apoptose in vivo induzida pelo veneno da serpente Bothrops alternatus em células musculares esqueléticas. Cinco coelhos machos, adultos, receberam 150µg/kg de veneno no músculo vasto lateral, enquanto outros cinco animais receberam 0,1% de BSA diluído em PBS no mesmo local. Após 12 horas, os animais foram eutanasiados, e amostras do local de inoculação foram coletadas para análise histopatológica. Foram evidenciadas necrose e hemorragia nas células musculares. Além disso, a análise imuno-histoquímica para identificação de caspase-3 ativada revelou marcações granulares e agregadas no citoplasma das células musculares, compatíveis com o processo de apoptose. Este é o primeiro relato que confirma o veneno de B. alternatus como causador de apoptose in vivo em células musculares esqueléticas.(AU)


Asunto(s)
Animales , Conejos , Apoptosis/efectos de los fármacos , Bothrops , Venenos de Crotálidos/envenenamiento , Músculos/fisiopatología
8.
Braz J Med Biol Res ; 51(9): e7552, 2018 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-29972429

RESUMEN

Guarana (Paullinia cupana) is habitually ingested by people in the Amazon region and is a key ingredient in various energy drinks consumed worldwide. Extension in longevity and low prevalence of chronic age-related diseases have been associated to habitual intake of guarana. Anti-aging potential of guarana was also demonstrated in Caenorhabditis elegans; however, the mechanisms involved in its effects are not clear. Herein, we investigated the putative pathways that regulate the effects of guarana ethanolic extract (GEE) on lifespan using C. elegans. The major known longevity pathways were analyzed through mutant worms and RT-qPCR assay (DAF-2, DAF-16, SKN-1, SIR-2.1, HSF-1). The possible involvement of purinergic signaling was also investigated. This study demonstrated that GEE acts through antioxidant activity, DAF-16, HSF-1, and SKN-1 pathways, and human adenosine receptor ortholog (ADOR-1) to extend lifespan. GEE also downregulated skn-1, daf-16, sir-2.1 and hsp-16.2 in 9-day-old C. elegans, which might reflect less need to activate these protective genes due to direct antioxidant effects. Our results contribute to the comprehension of guarana effects in vivo, which might be helpful to prevent or treat aging-associated disorders, and also suggest purinergic signaling as a plausible therapeutic target for longevity studies.


Asunto(s)
Antioxidantes/farmacología , Caenorhabditis elegans/efectos de los fármacos , Paullinia/química , Extractos Vegetales/farmacología , Envejecimiento/efectos de los fármacos , Animales , Antioxidantes/aislamiento & purificación , Caenorhabditis elegans/fisiología , Longevidad/efectos de los fármacos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Tiempo
9.
J Med Entomol ; 55(5): 1349-1353, 2018 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-29897558

RESUMEN

Leishmaniasis is a vector-borne disease caused by the protozoan Leishmania and it is one of the six most important infectious diseases in the world. The aim of this study was to conduct a research on the fauna and most frequented ecotopes by sandflies on islands of the Paraná River. The sandflies were collected with Falcão light traps in 10 islands in the municipalities of São Pedro do Paraná, Porto Rico, and Querência do Norte, in Paraná State, Brazil, from November 2012 to November 2014. In total, 76,145 specimens of Nyssomyia neivai, the only species found, were collected, of which 63,015 were female and 13,130, male. The largest number of sandflies was collected mainly in domiciles and peridomiciles. The islands of the Paraná River showed predominance of Ny. neivai, which is largely involved in the transmission of Leishmania and a risk of human leishmaniasis to the island inhabitants and tourists.


Asunto(s)
Distribución Animal , Psychodidae , Animales , Brasil , Femenino , Islas , Masculino , Densidad de Población , Ríos
10.
Mediators Inflamm ; 2018: 6148351, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29670464

RESUMEN

Calophyllum brasiliense is a plant from the Brazilian rain forests and has been used in folk medicine for the treatment of various diseases, including leishmaniasis. This infectious disease depends on the Leishmania sp. and the host immune response. C. brasiliense antileishmanial activity is well known, but the effects on immune response remain to be investigated. This study showed the leishmanicidal and immunomodulatory effects of a 30 µg/mL of hydroalcoholic extract of C. brasiliense in murine macrophages before and after Leishmania (Leishmania) amazonensis infection. The semiquantitative cytokine RNA expression was determined by RT-PCR and the anti-Leishmania activity was measured by infection index (IF). Hydroalcoholic extract of C. brasiliense reduced more than 95% of IF when used before and after Leishmania infection, with 3 and 24 h of treatment (p < 0.05). C. brasiliense inhibited or reduced significantly (p < 0.05) the TNF-α, IL-1ß, IL-18, and IL-10 mRNA expression. The antileishmanial and anti-inflammatory effects showed the potential of C. brasiliense as an alternative therapy for leishmaniasis and it must be investigated.


Asunto(s)
Calophyllum/química , Leishmania/efectos de los fármacos , Leishmania/patogenicidad , Animales , Femenino , Interleucina-10/metabolismo , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Leishmaniasis/tratamiento farmacológico , Leishmaniasis/parasitología , Ratones , Ratones Endogámicos BALB C , Extractos Vegetales/uso terapéutico , Factor de Necrosis Tumoral alfa/metabolismo
11.
Neotrop Entomol ; 47(4): 508-516, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29307103

RESUMEN

Samples collected in "restinga" areas of two conservation units in Rio de Janeiro state revealed the presence of two new species of Neanuridae family. The first, Pseudachorutes solaris sp. nov., from Parque Estadual da Costa do Sol and from Parque Nacional da Restinga de Jurubatiba, differs from other species for having 34-50 vesicles in the postantennal organ, and the second, Friesea jurubatiba sp. nov. from Parque Nacional da Restinga de Jurubatiba, differs from other species for having 8 clavate chaetae in the abdominal segment VI.


Asunto(s)
Artrópodos/anatomía & histología , Artrópodos/clasificación , Animales , Brasil , Conservación de los Recursos Naturales , Femenino , Masculino
12.
Photodiagnosis Photodyn Ther ; 21: 239-245, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29275066

RESUMEN

This study investigated the activity of photosensitive phthalocyanines on promastigotes and amastigotes of Leishmania (L.) amazonensis. Aluminum phthalocyanine chloride (AlPcCl), Aluminum phthalocyanine hydroxide (AlPcOH) and zinc phthalocyanine (PcZn) were tested in the presence (matte red LED, potency of 2.5-2.3 µW for 30 min) and absence of light against L. amazonensis promastigotes and the parasite viability was evaluated after 24, 48 and 72 h. The amastigote forms were treated with AlPcCl and AlPcOH, following the same lighting protocols described for the promastigote forms, being evaluated after 24 h. Cytotoxicity to human erythrocytes and peritoneal macrophages was also evaluated. The results showed that AlPcCl and AlPcOH in the presence of light have antileishmania activity, with leishmanistatic effects on promastigotes and amastigotes of L. amazonensis, without causing cytotoxicity to peritoneal macrophages and erythrocytes. The concentrations that inhibited 50% of the promastigote forms after 24 h of light exposure were 0.21 ±â€¯0.08 µM for AlPcCl and 0.23 ±â€¯0.06 µM for AlPcOH. In 48 h and 72 h after the treatment, the IC50 of AlPcCl was 0.13 ±â€¯0.02 and 0.12 ±â€¯0.03 µM and for AlPcOH was 0.14 ±â€¯0.01 µM and 0.11 ±â€¯0.01 µM, respectively. PcZn showed no activity on promastigotes of L. amazonensis. This study showed a substantial photodynamic activity of the phthalocyanines AlPcCl and AlPcOH against intracellular amastigotes forms of L. amazonensis after irradiation, presenting IC50 values of 0.62 ±â€¯0.06 µM and 0.92 ±â€¯0.12 µM, respectively. These results support the possibility of using photodynamic therapy for the treatment of cutaneous leishmaniasis.


Asunto(s)
Indoles/química , Indoles/farmacología , Leishmania/efectos de los fármacos , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/farmacología , Animales , Eritrocitos/efectos de los fármacos , Humanos , Isoindoles , Macrófagos/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Compuestos Organometálicos/química , Compuestos Organometálicos/farmacología , Fármacos Fotosensibilizantes/química , Compuestos de Zinc
13.
Braz. j. med. biol. res ; 51(9): e7552, 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-951753

RESUMEN

Guarana (Paullinia cupana) is habitually ingested by people in the Amazon region and is a key ingredient in various energy drinks consumed worldwide. Extension in longevity and low prevalence of chronic age-related diseases have been associated to habitual intake of guarana. Anti-aging potential of guarana was also demonstrated in Caenorhabditis elegans; however, the mechanisms involved in its effects are not clear. Herein, we investigated the putative pathways that regulate the effects of guarana ethanolic extract (GEE) on lifespan using C. elegans. The major known longevity pathways were analyzed through mutant worms and RT-qPCR assay (DAF-2, DAF-16, SKN-1, SIR-2.1, HSF-1). The possible involvement of purinergic signaling was also investigated. This study demonstrated that GEE acts through antioxidant activity, DAF-16, HSF-1, and SKN-1 pathways, and human adenosine receptor ortholog (ADOR-1) to extend lifespan. GEE also downregulated skn-1, daf-16, sir-2.1 and hsp-16.2 in 9-day-old C. elegans, which might reflect less need to activate these protective genes due to direct antioxidant effects. Our results contribute to the comprehension of guarana effects in vivo, which might be helpful to prevent or treat aging-associated disorders, and also suggest purinergic signaling as a plausible therapeutic target for longevity studies.


Asunto(s)
Animales , Extractos Vegetales/farmacología , Caenorhabditis elegans/efectos de los fármacos , Paullinia/química , Antioxidantes/farmacología , Factores de Tiempo , Envejecimiento/efectos de los fármacos , Caenorhabditis elegans/fisiología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Longevidad/efectos de los fármacos , Antioxidantes/aislamiento & purificación
14.
Braz. j. biol ; 76(3): 718-725, graf
Artículo en Inglés | LILACS | ID: lil-785043

RESUMEN

Abstract This study aimed to model the habitat suitability for an invasive clam Corbicula fluminea in a coastal shallow lagoon in the southern Neotropical region (–30.22, –50.55). The lagoon (19km2, maximum deep 2.5m) was sampled with an Ekman dredge in an orthogonal matrix comprising 84 points. At each sampling point, were obtained environmental descriptors as depth, organic matter content (OMC), average granulometry (Avgran), and the percentage of sand (Pcsand). Prediction performance of Generalized Linear Models (GLM), Generalized Additive Models (GAM) and Boosted Regression Tree (BRT) were compared. Also, niche overlapping with other native clam species (Castalia martensi, Neocorbicula limosa and Anodontites trapesialis) was examined. A BRT model with 1400 trees was selected as the best model, with cross-validated correlation of 0.82. The relative contributions of predictors were Pcsand-42.6%, OMC-35.8%, Avgran-10.9% and Depth-10.8%. Were identified that C. fluminea occur mainly in sandy sediments with few organic matter, in shallow areas nor by the shore. The PCA showed a wide niche overlap with the native clam species C. martensi, N. limosa and A. trapesialis.


Resumo O objetivo de deste estudo foi modelar a adequabilidade de habitat do bivalve invasor Corbicula fluminea em uma lagoa costeira na região Neotropical (–30.22, –50.55). A lagoa (19km2, 2,5 m de profundidade máxima) foi amostrada com uma draga Ekman em uma matriz ortogonal compreendendo 84 pontos. Em cada ponto de amostragem foram obtidos descritores ambientais como a profundidade, teor de matéria orgânica (OMC), granulometria média (Avgran), e a percentagem de areia (Pcsand). O poder preditivo dos métodos Modelos Lineares Generalizados (GLM), Modelos Aditivos Generalizados (GAM) e Boosted Regression Trees (BRT) foram comparados. Além disso, a sobreposição de nicho com espécies de moluscos nativos (Castalia martensi, Neocorbicula limosa e Anodontites trapesialis) foi examinada. Um modelo BRT com 1.400 árvores foi selecionado como o melhor modelo, com correlação da validação cruzada de 0,82. As contribuições relativas dos preditores foram Pcsand-42,6%, OMC-35,8%, Avgran-10,9% e profundidade-10,8%. Foi demonstrado que C. fluminea está associada a sedimentos arenosos com pouca matéria orgânica, em áreas rasas próximo às margens. A PCA mostrou uma ampla sobreposição de nicho com as espécies de moluscos nativos C. martensi, N. limosa e A. trapesialis.


Asunto(s)
Animales , Ecosistema , Corbicula , Especies Introducidas/estadística & datos numéricos , Brasil , Dinámica Poblacional , Monitoreo del Ambiente , Densidad de Población , Modelos Teóricos
15.
Braz J Biol ; 76(3): 718-25, 2016 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-27097092

RESUMEN

This study aimed to model the habitat suitability for an invasive clam Corbicula fluminea in a coastal shallow lagoon in the southern Neotropical region (-30.22, -50.55). The lagoon (19km2, maximum deep 2.5m) was sampled with an Ekman dredge in an orthogonal matrix comprising 84 points. At each sampling point, were obtained environmental descriptors as depth, organic matter content (OMC), average granulometry (Avgran), and the percentage of sand (Pcsand). Prediction performance of Generalized Linear Models (GLM), Generalized Additive Models (GAM) and Boosted Regression Tree (BRT) were compared. Also, niche overlapping with other native clam species (Castalia martensi, Neocorbicula limosa and Anodontites trapesialis) was examined. A BRT model with 1400 trees was selected as the best model, with cross-validated correlation of 0.82. The relative contributions of predictors were Pcsand-42.6%, OMC-35.8%, Avgran-10.9% and Depth-10.8%. Were identified that C. fluminea occur mainly in sandy sediments with few organic matter, in shallow areas nor by the shore. The PCA showed a wide niche overlap with the native clam species C. martensi, N. limosa and A. trapesialis.


Asunto(s)
Corbicula , Ecosistema , Especies Introducidas/estadística & datos numéricos , Animales , Brasil , Monitoreo del Ambiente , Modelos Teóricos , Densidad de Población , Dinámica Poblacional
16.
Animal ; 10(3): 490-9, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26584672

RESUMEN

The aim of this study was to analyze the economic viability of producing dairy goat kids fed liquid diets in alternative of goat milk and slaughtered at two different ages. Forty-eight male newborn Saanen and Alpine kids were selected and allocated to four groups using a completely randomized factorial design: goat milk (GM), cow milk (CM), commercial milk replacer (CMR) and fermented cow colostrum (FC). Each group was then divided into two groups: slaughter at 60 and 90 days of age. The animals received Tifton hay and concentrate ad libitum. The values of total costs of liquid and solid feed plus labor, income and average gross margin were calculated. The data were then analyzed using the Monte Carlo techniques with the @Risk 5.5 software, with 1000 iterations of the variables being studied through the model. The kids fed GM and CMR generated negative profitability values when slaughtered at 60 days (US$ -16.4 and US$ -2.17, respectively) and also at 90 days (US$ -30.8 and US$ -0.18, respectively). The risk analysis showed that there is a 98% probability that profitability would be negative when GM is used. In this regard, CM and FC presented low risk when the kids were slaughtered at 60 days (8.5% and 21.2%, respectively) and an even lower risk when animals were slaughtered at 90 days (5.2% and 3.8%, respectively). The kids fed CM and slaughtered at 90 days presented the highest average gross income (US$ 67.88) and also average gross margin (US$ 18.43/animal). For the 60-day rearing regime to be economically viable, the CMR cost should not exceed 11.47% of the animal-selling price. This implies that the replacer cannot cost more than US$ 0.39 and 0.43/kg for the 60- and 90-day feeding regimes, respectively. The sensitivity analysis showed that the variables with the greatest impact on the final model's results were animal selling price, liquid diet cost, final weight at slaughter and labor. In conclusion, the production of male dairy goat kids can be economically viable when the kids diet consists mainly of either cow milk or fermented colostrum, especially when kids are slaughtered at 90 days of age.


Asunto(s)
Alimentación Animal/economía , Crianza de Animales Domésticos/economía , Calostro , Dieta/veterinaria , Cabras , Sustitutos de la Leche/economía , Envejecimiento , Alimentación Animal/análisis , Animales , Líquidos Corporales , Peso Corporal , Bovinos , Femenino , Fermentación , Masculino , Leche , Método de Montecarlo , Embarazo
17.
Genet Mol Res ; 14(4): 14929-35, 2015 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-26600554

RESUMEN

Leishmaniasis is a parasitic infectious disease with global repercussions. American cutaneous leishmaniasis (ACL) is endemic in southern Brazil and its pathogenesis varies according to parasite species, immune response, and host genetics. In terms of immunogenetics, many host genes, including HLA (human leukocyte antigen), could be involved in susceptibility to and protection against ACL. Accordingly, the aim of this study was to investigate the association between HLA class I genes (HLA-A, -B, and -C) and ACL in an endemic region of southern Brazil. The allele frequencies of 186 patients diagnosed with ACL and 278 healthy individuals were compared. HLA class I (HLA-A, -B, and -C) typing was carried out by PCR-SSO using Luminex technology. The results revealed an association between the HLA-C*04 allele and the patient study group, in which it appeared more frequently than in the control group [21.5 vs 13.49% (P = 0.0016 and Pc = 0.0258; OR = 1.7560; 95%CI = 1.2227-2.5240)], thereby suggesting an increased susceptibility to ACL. Additional allelic groups such as HLA-A*02, HLA-B*35, HLA-B*45, HLA-C*01, and HLA-C*15 were also implicated; however, further investigation is necessary to confirm their association with ACL. Therefore, the results obtained in this study demonstrate the involvement of HLA class I genes in the susceptibility or resistance to ACL, with significant association between HLA-C*04 and ACL susceptibility.


Asunto(s)
Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Antígenos HLA-C/genética , Leishmaniasis Cutánea/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Brasil , Femenino , Frecuencia de los Genes , Genotipo , Antígenos HLA/genética , Antígenos HLA-B/genética , Humanos , Leishmaniasis Cutánea/patología , Masculino , Persona de Mediana Edad
18.
Braz J Biol ; 75(2): 477-83, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26132035

RESUMEN

Regnellidium diphyllum Lindm. is a heterosporous fern which grows in shallow waters and wetlands, and water pollution contributes to its vulnerability. Environmental lead contamination is mostly caused by industrial and agricultural residues as well as domestic sewage. Given its persistence in the environment, lead can cause important toxicity in living organisms. Megaspore germination and the initial growth of R. diphyllum sporophytes were assessed in Meyer's solution with lead nitrate (Pb(NO3)2) concentrations of 0 (control), 1, 5, 10 and 50 mg L(-1). The study was conducted in a growth chamber at 25 ± 1°C and a 12 hour photoperiod with a nominal irradiance of 100 µmol m(-2) s(-1), for 28 days. Lead concentration in sporophytes was assessed using atomic absorption spectrometry. In the absence of lead, 74% of spores germinated, while significantly lower germination percentages were observed in Pb(NO3)2 concentrations of 1, 10 and 50 mg L(-1). The presence of lead did not significantly influence root growth. At 28 days, primary leaf development was significantly lower in Pb(NO3)2 concentrations of 5 mg L(-1) and higher in relation to the control. The length of secondary leaves did not significantly differ between sporophytes exposed to different concentrations of lead and those of the control at 28 days. Sporophytes exposed to 10 and 50 mg L(-1) Pb(NO3)2 accumulated 1129 mg kg(-1) and 5145 mg kg(-1) of Pb, respectively. The presence of high levels of lead in R. diphyllum sporophytes did not prevent initial development. Future studies should investigate the ability of the species to accumulate and tolerate high levels of lead in advanced stages of its development and in environmental conditions.


Asunto(s)
Germinación/efectos de los fármacos , Plomo/toxicidad , Marsileaceae/efectos de los fármacos , Esporas/efectos de los fármacos , Marsileaceae/crecimiento & desarrollo , Espectrofotometría Atómica , Esporas/crecimiento & desarrollo
19.
Braz. j. biol ; 75(2): 477-483, 05/2015. graf
Artículo en Inglés | LILACS | ID: lil-749690

RESUMEN

Regnellidium diphyllum Lindm. is a heterosporous fern which grows in shallow waters and wetlands, and water pollution contributes to its vulnerability. Environmental lead contamination is mostly caused by industrial and agricultural residues as well as domestic sewage. Given its persistence in the environment, lead can cause important toxicity in living organisms. Megaspore germination and the initial growth of R. diphyllum sporophytes were assessed in Meyer's solution with lead nitrate (Pb(NO3)2) concentrations of 0 (control), 1, 5, 10 and 50 mg L–1. The study was conducted in a growth chamber at 25±1°C and a 12 hour photoperiod with a nominal irradiance of 100 μmol m–2 s–1, for 28 days. Lead concentration in sporophytes was assessed using atomic absorption spectrometry. In the absence of lead, 74% of spores germinated, while significantly lower germination percentages were observed in Pb(NO3)2 concentrations of 1, 10 and 50 mg L–1. The presence of lead did not significantly influence root growth. At 28 days, primary leaf development was significantly lower in Pb(NO3)2 concentrations of 5 mg L–1 and higher in relation to the control. The length of secondary leaves did not significantly differ between sporophytes exposed to different concentrations of lead and those of the control at 28 days. Sporophytes exposed to 10 and 50 mg L–1 Pb(NO3)2 accumulated 1129 mg kg–1 and 5145 mg kg–1 of Pb, respectively. The presence of high levels of lead in R. diphyllum sporophytes did not prevent initial development. Future studies should investigate the ability of the species to accumulate and tolerate high levels of lead in advanced stages of its development and in environmental conditions.


Regnellidium diphyllum Lindm. é uma samambaia heterosporada que se desenvolve em águas rasas ou em solos úmidos, sendo que a poluição da água contribui para sua vulnerabilidade. A contaminação ambiental por chumbo ocorre principalmente por resíduos industriais e agrícolas, bem como por efluentes domésticos. Devido à sua persistência no ambiente, esse metal pode apresentar importante toxicidade aos organismos vivos. A germinação de megásporos e o desenvolvimento inicial de esporófitos de R. diphyllum foram avaliados em solução de Meyer com concentrações de 0 (controle), 1, 5, 10 e 50 mg L–1 de nitrato de chumbo (Pb(NO3)2). O estudo foi conduzido em câmara de germinação a 25±1 °C e fotoperíodo de 12 horas sob irradiância nominal de 100 μmol m–2 s–1, por 28 dias. A concentração de chumbo em esporófitos foi analisada por espectrometria de absorção atômica. Na ausência de chumbo, 74% dos esporos germinaram, enquanto que porcentagens de germinação significantemente menores foram observadas nas concentrações de 1, 10 e 50 mg L–1 de Pb(NO3)2. A presença de chumbo não influenciou significativamente o crescimento das raízes. O desenvolvimento das folhas primárias foi significativamente menor em relação ao controle a partir de 5 mg L–1 de Pb(NO3)2 aos 28 dias. O comprimento das folhas secundárias não diferiu significativamente entre esporófitos expostos às diferentes concentrações de chumbo e aqueles do controle, aos 28 dias. Esporófitos expostos a 10 e 50 mg L–1 de Pb(NO3)2 acumularam 1129 mg kg–1 e 5145 mg kg–1 de Pb, respectivamente. A presença de altas concentrações de chumbo nos esporófitos de R. diphyllum não impediu seu desenvolvimento inicial. Estudos futuros deverão investigar a capacidade de a espécie acumular e tolerar altas concentrações de chumbo em estádios avançados de desenvolvimento e também em condições ambientais.


Asunto(s)
Germinación/efectos de los fármacos , Plomo/toxicidad , Marsileaceae/efectos de los fármacos , Esporas/efectos de los fármacos , Marsileaceae/crecimiento & desarrollo , Espectrofotometría Atómica , Esporas/crecimiento & desarrollo
20.
Asian-Australas J Anim Sci ; 28(1): 135-42, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25557685

RESUMEN

This study was conducted to evaluate the effect of inclusion of propolis extraction residue in the feed of broilers from 1 to 21 d of age on phagocytic activity of macrophages, cutaneous basophil hypersensitivity response to phytohemagglutinin, antibody production against Newcastle disease, lymphoid organ weight and hematological profile and to determine the optimal level of inclusion. 120 chicks, reared in metabolism cages until 21 days of age, were distributed in a completely randomized design, with five treatments (0%, 1%, 2%, 3%, and 4% of propolis residue) and six replications. The relative weight of thymus and monocyte percentage were affected by propolis residue, with a quadratic response (p<0.05) and lowest values estimated at 2.38% and 2.49%, respectively. Changes in relative weight of cloacal bursa and spleen, percentage of lymphocyte, heterophil, basophil, eosinophil, and heterophil:lymphocyte ratio, antibody production against Newcastle disease, phagocytic activity of macrophages and the average number of phagocytosed erythrocytes were not observed. The nitric oxide production with regard to positive control (macrophages+erythrocytes) decreased linearly (p<0.05) with increased doses of propolis residue. The remaining variables of nitric oxide production (negative control - macrophages, and difference between the controls) were not affected by propolis residue. The cutaneous basophil hypersensitivity response to phytohemagglutinin as determined by the increase in interdigital skin thickness exhibited a quadratic response (p<0.05), which predicted a lower reaction response at a dose of 2.60% of propolis residue and highest reaction response after 43.05 hours of phytohemagglutinin injection. The inclusion of 1% to 4% of propolis extraction residue in broiler diets from 1 to 21 days of age was not able to improve the immune parameters, despite the modest changes in the relative weight in thymus, blood monocyte percentage, nitric oxide concentration, and interdigital reaction to phytohemagglutinin.

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