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1.
Trop Anim Health Prod ; 52(4): 1933-1943, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31965413

RESUMEN

The absence of formal markets and the large variability of genetic groups and production systems of goats and sheep in developing countries hinder the implementation of traditional breeding programmes. Community-based breeding programmes (CBBP) for these species have been shown to be effective in these countries. In these programmes, the definition of the objectives and criteria of selection is done in a participatory way, which takes into account the desires and needs of the local farmers. We aimed to define the objectives and criteria of a CBBP for goats and sheep in the Inhamuns region, Ceará, Brazil, using a participatory rural appraisal (PRA). This methodology, which consist in an approach that aims to incorporate the knowledge and opinions of rural people in the planning and management of development projects and programmes, was performed in seven districts of two towns of the region (Tauá and Parambu). One hundred twenty-two farmer families participated in the survey. The PRA was able to provide important information, and its results showed that breeders of this region keep flocks of goats and sheep for social, economic and cultural benefits. In order of importance, the main objectives for goat farming were personal fulfilment (PERF), food source for family (FSF), income generation (INCG), savings (SAV) and cultural/family traditions (CULT), while for sheep farming were CULT, FSF, SAV, PERF and INCG. Disease resistance (RDI), adaptability (ADP), fertility (FERT), growth rate (GRA), host resistance of worms (HRW), body conformation (BC), temperament (TEM), longevity (LONG), body size (BSIZ), age at first kidding (AFK) and milk yield (MIY) were the main selection criteria that farmers use for goats. The most important selection criteria used for selecting sheep were ADP, RDI, HRW, GRA, FERT, LONG, BC, BS and age at first lambing. According to these objectives and criteria, the CBBP must consider the adaptation of the animals to the climate and management conditions of the region, the resistance to diseases and productive performance.


Asunto(s)
Cruzamiento/métodos , Participación de la Comunidad , Agricultores/psicología , Cabras , Oveja Doméstica , Adulto , Anciano , Anciano de 80 o más Años , Crianza de Animales Domésticos , Animales , Brasil , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
2.
J Appl Microbiol ; 126(5): 1402-1413, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30659746

RESUMEN

AIM: To screen and identify a potential biosurfactant-producing yeast strain isolated from Antarctic soil and to evaluate the fermentation process kinetics of the most promising strain on biosurfactant production using glycerol as carbon source. METHODS AND RESULTS: From the 68 isolated yeast strains, 11 strains were able to produce biosurfactants after Emulsification Index (E.I.) and Drop Collapse tests, reaching an E.I. higher than 10%. Strain 1_4.0 was the best producer, identified as Candida glaebosa based on molecular analysis. Yeast was cultivated in a medium composed of glycerol supplemented with yeast extract for 120 h to determine the process kinetics. The increased C/N ratio affected yeast growth and biosurfactant production. Biosurfactant release was associated with the end of exponential and beginning of the stationary growth phases. Results indicated an E.I. of 30% at the end of the fermentation. CONCLUSIONS: The feasiability of C. glaebosa to produce biosurfactant from a low-cost medium cultivation shows a great impact on the development of bioresource in the Antarctica terrestrial environment. SIGNIFICANCE AND IMPACT OF THE STUDY: Although the diversity of psychrophilic/psychrotolerant micro-organisms from Antarctica has been the preferred subject of study by microbiologists, terrestrial microfungal communities are scarcely investigated and literature about the biotechnological potential of such micro-organisms should cover important biomolecules in addition to cold-adapted enzymes. In the present study, for the first time, the Maritime Antarctica environment was screened as a novel source of biosurfactants produced by micro-organisms.


Asunto(s)
Candida/metabolismo , Microbiología del Suelo , Tensoactivos/metabolismo , Regiones Antárticas , Candida/aislamiento & purificación , Glicerol/metabolismo , Islas , Cinética , Tensoactivos/aislamiento & purificación , Levaduras/crecimiento & desarrollo , Levaduras/aislamiento & purificación , Levaduras/metabolismo
3.
Med Vet Entomol ; 33(1): 121-130, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30125976

RESUMEN

Pesticides are used worldwide to control arthropod parasites in cattle herds. The indiscriminate and/or inappropriate use of pesticides without veterinary guidance is a reality in several countries of South America. Improper pesticide use increases the chances of contamination of food and the environment with chemical pesticides and their metabolites. Reduction of these contamination events is an increasing challenge for those involved in livestock production. The horn fly, Haematobia irritans (Linnaeus) (Diptera: Muscidae), is one of the most economically important parasites affecting cattle herds around the world. As such, horn fly control efforts are often required to promote the best productive performance of herds. Pesticide susceptibility bioassays revealed that pyrethroid resistance was widespread and reached high levels in horn fly populations in the Brazilian state of Rondônia. The knockdown resistance (kdr) sodium channel gene mutation was detected in all horn fly populations studied (n = 48), and the super kdr sodium channel gene mutation was found in all homozygous resistant kdr individuals (n = 204). Organophosphate resistance was not identified in any of the fly populations evaluated.


Asunto(s)
Resistencia a los Insecticidas/genética , Insecticidas/farmacología , Muscidae/efectos de los fármacos , Organofosfatos/farmacología , Piretrinas/farmacología , Animales , Brasil , Muscidae/genética
4.
J Fish Biol ; 92(5): 1446-1462, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29582420

RESUMEN

A re-evaluation of Dekeyseria brachyura and D. pulchra found them to be junior synonyms of D. picta, the oldest species among these congeners, based on continuous intraspecific variation in morphometrics and colour pattern. Examination of material deposited at Brazilian and Venezuelan collections, including the original type specimens of Ancistrus brachyurus and A. pictus, plus samples recently collected in the Rio Negro, Amazonas, Brazil, allowed re-evaluation of the taxonomic status of D. picta and provides additional information on its distribution, habitats and reproductive strategies.


Asunto(s)
Bagres/clasificación , Ecosistema , Animales , Brasil , Bagres/anatomía & histología , Bagres/fisiología , Demografía , Femenino , Masculino , Caracteres Sexuales , Conducta Sexual Animal , Especificidad de la Especie , Venezuela
5.
Mol Psychiatry ; 21(1): 80-8, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25754084

RESUMEN

Chronic stress is a major risk factor for several human disorders that affect modern societies. The brain is a key target of chronic stress. In fact, there is growing evidence indicating that exposure to stress affects learning and memory, decision making and emotional responses, and may even predispose for pathological processes, such as Alzheimer's disease and depression. Lipids are a major constituent of the brain and specifically signaling lipids have been shown to regulate brain function. Here, we used a mass spectrometry-based lipidomic approach to evaluate the impact of a chronic unpredictable stress (CUS) paradigm on the rat brain in a region-specific manner. We found that the prefrontal cortex (PFC) was the area with the highest degree of changes induced by chronic stress. Although the hippocampus presented relevant lipidomic changes, the amygdala and, to a greater extent, the cerebellum presented few lipid changes upon chronic stress exposure. The sphingolipid and phospholipid metabolism were profoundly affected, showing an increase in ceramide (Cer) and a decrease in sphingomyelin (SM) and dihydrosphingomyelin (dhSM) levels, and a decrease in phosphatidylethanolamine (PE) and ether phosphatidylcholine (PCe) and increase in lysophosphatidylethanolamine (LPE) levels, respectively. Furthermore, the fatty-acyl profile of phospholipids and diacylglycerol revealed that chronic stressed rats had higher 38 carbon(38C)-lipid levels in the hippocampus and reduced 36C-lipid levels in the PFC. Finally, lysophosphatidylcholine (LPC) levels in the PFC were found to be correlated with blood corticosterone (CORT) levels. In summary, lipidomic profiling of the effect of chronic stress allowed the identification of dysregulated lipid pathways, revealing putative targets for pharmacological intervention that may potentially be used to modulate stress-induced deficits.


Asunto(s)
Encéfalo/metabolismo , Lípidos , Estrés Psicológico/metabolismo , Animales , Cromatografía Líquida de Alta Presión , Enfermedad Crónica , Modelos Animales de Enfermedad , Hidrocortisona/sangre , Masculino , Espectrometría de Masas , Ratas Wistar , Reacción en Cadena en Tiempo Real de la Polimerasa , Incertidumbre
6.
Asian-Australas J Anim Sci ; 27(2): 284-9, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25049953

RESUMEN

The experiment was conducted to evaluate the ingestive behavior of lambs confined in individual and group stalls. We used thirty-four lambs in their growing phase, aged an average of three months, with mean initial live weight of 17.8±5.2 kg. They were allotted in a completely randomized design with 24 animals kept in individual stalls and 10 animals confined as a group. The experiment lasted for a total of 74 days, and the first 14 days were dedicated to the animals' adaption to the management, facilities and diets. The data collection period lasted 60 days, divided into three 20-d periods for the behavior evaluation. The animals were subjected to five days of visual observation during the experiment period, by the quantification of 24 h a day, with evaluations on the 15th day of each period and an interim evaluation consisting of two consecutive days on the 30th and 31st day of the experiment. The animals confined as a group consumed less (p<0.05) fiber. However, the animals confined individually spent less (p<0.05) time on feeding, rumination and chewing activities and longer in idleness. Therefore, the lower capacity of lambs confined in groups to select their food negatively affects their feeding behavior.

7.
Asian-Australas J Anim Sci ; 27(11): 1584-92, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25358318

RESUMEN

The objective was to evaluate the ingestive behavior of crossbred heifers finished on a Brachiaria brizantha cv. Marandu pasture receiving four levels of glycerin in their supplementation. Thirty-six crossbred heifers with average initial weight of 264.83±3.83 kg and 20 months of age were distributed into a completely randomized design with four treatments and nine replications: control (0%), 4.82%, 10.12%, and 15.56% glycerin in the dry matter. The grazing time reduced linearly (p<0.05), whereas the time spent on activities like rumination, idleness, trough and total chewing time were quadratically affected (p<0.05). Bite rate and number of bites/day were quadratically influenced (p<0.05). The number of bites/swallowed cud and the number of bites/minute, however, increased linearly (p<0.05). Although the time spent on each cud and number of chews per cud were not affected (p>0.05). The number of rumination periods reduced linearly (p<0.05), whereas the number of grazing, idle and trough periods, and the times per grazing, idle, rumination and trough periods were quadratically affected (p<0.05). The feed and rumination efficiencies of the dry matter, non-fibrous carbohydrates, pasture dry matter and concentrate were quadratically affected (p>0.05) whereas the feed efficiency of neutral detergent fiber reduced linearly (p<0.05). Addition of glycerin in substitution of corn in supplements for animals managed on pastures does not influenced feed intake, but reduces the grazing time and increases the idle time. The supplementation also improves feed and rumination efficiencies.

8.
Braz J Microbiol ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38954219

RESUMEN

Fusarium oxysporum is a cross-kingdom pathogen that infects humans, animals, and plants. The primary concern regarding this genus revolves around its resistance profile to multiple classes of antifungals, particularly azoles. However, the resistance mechanism employed by Fusarium spp. is not fully understood, thus necessitating further studies to enhance our understanding and to guide future research towards identifying new drug targets. Here, we employed an untargeted proteomic approach to assess the differentially expressed proteins in a soil isolate of Fusarium oxysporum URM7401 cultivated in the presence of amphotericin B and fluconazole. In response to antifungals, URM7401 activated diverse interconnected pathways, such as proteins involved in oxidative stress response, proteolysis, and lipid metabolism. Efflux proteins, antioxidative enzymes and M35 metallopeptidase were highly expressed under amphotericin B exposure. Antioxidant proteins acting on toxic lipids, along with proteins involved in lipid metabolism, were expressed during fluconazole exposure. In summary, this work describes the protein profile of a resistant Fusarium oxysporum soil isolate exposed to medical antifungals, paving the way for further targeted research and discovering new drug targets.

9.
Int J Biol Macromol ; 277(Pt 4): 134486, 2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39102913

RESUMEN

Food from animal sources (e.g., fish) represents the food group most likely to disseminate diseases to humans. To prevent food contamination and foodborne illnesses, intelligent packaging has been developed to monitor fish freshness by real-time tracking their physicochemical attributes and informing consumers about their conservation state. In this context, we investigated the influence of ionic strength (IS) provided by CaCl2 on the chromatic response of anthocyanin açai extracts incorporated into methylcellulose (MC) within hydrocolloid-based colorimetric sensors for monitoring the freshness of Lambari fish. The color sensitivity of the sensors was modulated by IS in the presence of NH3 volatile and/or TVB-N. Increasing IS led to a plasticizing effect in the MC matrix, which influenced the chromatic properties of anthocyanin in the presence of NH3 and/or TVB-N. The perception of distinct colors by untrained eyes improved from 10 min with the control sensor to 2.5 min for sensors with IS >50 mM. Adjusting the IS to 500 mM with LiCl, CaCl2, or MgCl2 resulted in gray-green, blue, or moss-green colors, respectively, diverging from the control sensor's color (pink and gray) after 10 min of ammonia exposure, confirming salt-induced copigmentation. Color irreversibility in the sensors was achieved when the IS exceeded 250 mM. Through principal component analysis, we statistically validate the efficacy of the sensor in assessing the freshness of Lambari fish. The sensor maintained its color-change capability even after 60 d of storage and was able to classify Lambari fish freshness according to Brazilian and European standards. This study elucidates the interrelation between the structures and properties of natural compounds such as MC, anthocyanin, and CaCl2, providing a method to control the chromatic properties of sensors intended to monitor food quality, safety, and shelf-life.

10.
Braz J Biol ; 84: e281286, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38629678

RESUMEN

Salinity reduces feijão-caupi production, and the search for tolerant varieties becomes important within the agricultural context, as, in addition to being used in the field, they can be used in genetic improvement. The objective was to for a identify variety that is tolerant to salinity considering the physiological quality of seeds and seedling growth. A 2 × 4 factorial scheme was used, referring to the varieties Pingo-de-ouro and Coruja, and four electrical conductivities of water (0; 3.3; 6.6 and 9.9 dS m-1). The physiological quality of seeds and the growth of seedlings were analyzed, in addition to the cumulative germination. The Pingo-de-ouro variety showed no germination, length of the shoot and root, dry mass of the shoot and root compromised up to electrical conductivity of 6 dS m-1 in relation to 0.0 dS m-1. On the other hand, the Coruja variety showed reduced germination, increased shoot and root length. The creole variety Pingo-de-ouro proved to be tolerant to salinity.


Asunto(s)
Vigna , Vigna/genética , Salinidad , Cloruro de Sodio , Plantones , Germinación/fisiología , Semillas/fisiología
11.
Asian-Australas J Anim Sci ; 26(2): 218-26, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25049779

RESUMEN

This experiment was conducted to evaluate the intake, nutrient apparent digestibility and the effect of total collection days (two and four days) on apparent digestibility estimates for lambs fed diets containing sugar cane treated with calcium oxide (CaO). Eight Santa Inês castrated male lambs with a 16.6±1.8 kg body weight were used. The lambs were distributed in two 4×4 Latin squares, with four experimental periods of 14 d each. The animals were kept in 1.2 m(2) individual pens, and the intake and digestibility evaluations were performed during the last four days of each period. The diets were formulated to be isonitrogenous, containing 14% crude protein (CP), and presenting 70% sugar cane treated with 0, 0.75, 1.5 or 2.25% of CaO (as-fed basis), corrected with 1% urea, and 30% concentrate. The sugar cane with added CaO was chopped, treated, and offered to the animals after 24 h of storage. The sugar cane with CaO increased the DM, OM, CP, NDF, NDFap, TC, NFCap and TDN intake (kg/d), when compared to natural sugar cane, and produced the same intake expressed as a percentage of body weight (% BW). The NFCap digestibility of the CaO-treated sugar cane was inferior to the NFCap digestibility in natural sugar cane. There was a linear increase in the DM intake with the CaO-added sugar cane, but the DM and NDF digestibility and the TDN content decreased linearly. The chemical treatment of sugar cane with CaO increases the intake but does not improve the nutrient digestibility. Two days of total fecal collection were found to be sufficient to estimate the total apparent digestibility in lambs.

12.
Ann Oncol ; 23(6): 1436-41, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22039084

RESUMEN

BACKGROUND: Preclinical data suggest that treatment with lapatinib reinduces sensitivity to trastuzumab in human epidermal growth factor receptor 2(HER2)-positive breast cancer cells. PATIENTS AND METHODS: Between January 2007 and November 2010, 179 HER2-positive metastatic breast cancer patients were treated with lapatinib and capecitabine at nine Italian institutions. We evaluated the clinical outcome of 69 patients (38.5%) retreated with trastuzumab after lapatinib progression. RESULTS: Visceral metastases were identified in 51 (74%) and brain metastases in 16 patients (23%). All patients were pretreated with both trastuzumab- and lapatinib-based therapy. We observed with retreatment with trastuzumab-based therapy: 1 complete remission (2%), 18 partial remission (29%) and 10 stable disease ≥6 months (14%) and 47% of clinical benefit (CB). Median duration of response was 8.1 months [95% confidence interval (CI) 5.5-10.7]. No unexpected toxic effects occurred. At a median follow-up of 13 months, median progression-free survival was 4.9 months (95% CI 4.2-5.6) and overall survival (OS) 19.4 months (95% CI 14.0-25.0). Median OS was longer for patients experiencing CB (not reached versus 13.4 months for patients without CB, P = 0.002). Brain involvement was associated with lower median OS (17.3 versus 23.3 months for patients without brain disease; P = 0.021). CONCLUSION: Retreatment with trastuzumab-based therapy showed CB in 47% of patients progressing during lapatinib-based therapy, leading to a prolonged OS.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Antineoplásicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Quinazolinas/farmacología , Receptor ErbB-2/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Resistencia a Antineoplásicos , Femenino , Humanos , Estimación de Kaplan-Meier , Lapatinib , Persona de Mediana Edad , Análisis Multivariante , Metástasis de la Neoplasia , Modelos de Riesgos Proporcionales , Quinazolinas/uso terapéutico , Estudios Retrospectivos , Trastuzumab , Insuficiencia del Tratamiento
13.
Ann Oncol ; 23(1): 135-141, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21531784

RESUMEN

BACKGROUND: Previous studies investigating the prognostic role of mucinous histology of colorectal cancer produced conflicting results. This retrospective analysis was carried out in order to explore whether mucinous adenocarcinoma (MC) is associated with a comparatively worse prognosis than that of nonmucinous adenocarcinoma (NMC) for patients undergoing curative resection for stage II and III colon cancer. PATIENTS AND METHODS: This study involved 1025 unselected patients who underwent curative surgery for sporadic colon cancer and follow-up procedures at six different oncology departments. RESULTS: MCs accounted for 17.4% (n=178) of tumours. Patients with MC had 5- and 8-year overall survival rates of 78.6% and 68.8%, respectively, compared with 72.3% and 63.8%, respectively, for patients with nonmucinous tumours. Multivariate analysis using the Cox proportional hazards model showed that the clinically significant prognostic factors were stage of disease and adjuvant chemotherapy. No statistically significant interaction between mucinous histology and adjuvant chemotherapy was found. CONCLUSIONS: For patients with stage II and III colon cancer who underwent curative surgery, mucinous histology has no significant correlation with prognosis compared with NMC. This retrospective analysis suggests a comparable benefit from adjuvant chemotherapy for MC compared with NMC.


Asunto(s)
Adenocarcinoma Mucinoso/mortalidad , Adenocarcinoma Mucinoso/patología , Neoplasias del Colon/mortalidad , Neoplasias del Colon/patología , Adenocarcinoma Mucinoso/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Quimioterapia Adyuvante , Neoplasias del Colon/cirugía , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos
14.
Mar Pollut Bull ; 182: 113957, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35872476

RESUMEN

Finfish aquaculture is a fast-growing primary industry and is increasingly common in coastal ecosystems. Bacterioplankton is ubiquitous in marine environment and respond rapidly to environmental changes. Changes in bacterioplankton community are not well understood in semi-enclosed stratified embayments. This study aims to examine aquaculture effects in the composition and functional profiles of the bacterioplankton community using amplicon sequencing along a distance gradient from two finfish leases in a marine embayment. Results revealed natural stratification in bacterioplankton associated to NOx, conductivity, salinity, temperature and PO4. Among the differentially abundant bacteria in leases, we found members associated with nutrient enrichment and aquaculture activities. Abundant predicted functions near leases were assigned to organic matter degradation, fermentation, and antibiotic resistance. This study provides a first effort to describe changes in the bacterioplankton community composition and function due to finfish aquaculture in a semi-enclosed and highly stratified embayment with a significant freshwater input.


Asunto(s)
Ecosistema , Plancton , Animales , Acuicultura , Organismos Acuáticos , Peces , Plancton/microbiología , ARN Ribosómico 16S
15.
Animal ; 15(2): 100088, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33712207

RESUMEN

Crude glycerin (CG) is a biodiesel byproduct that has been tested as an alternative feed additive for use in beef production. After being absorbed, it is used in the liver to produce glucose, an important precursor of intramuscular fat in ruminants. This study aimed to evaluate the effect of CG (439 g/kg glycerol) on the performance and meat quality of crossbred heifers finished in Urochloa brizantha cv. Marandu. Thirty-six heifers with an initial BW of 301.5 ±â€¯23.02 kg were used. They were supplemented for 154 days with the following levels of CG: mineral mixture (without CG), 33.3, 66.6 and 99.9 g/kg CG in the DM of the supplement. Supplement or pasture DM intakes, slaughter BW and carcass traits were not influenced (P > 0.05) by increasing levels of CG. The total fat content of the meat, the vaccenic (18:1 n-7t) and conjugated linoleic acid (18:2 c9-t11) increased with the addition of CG in the diet (P < 0.05). Crude glycerin can be included up to 99.9 g/kg of the total diet without changing the performance of crossbred heifers finished in the tropical pasture.


Asunto(s)
Alimentación Animal , Glicerol , Alimentación Animal/análisis , Animales , Bovinos , Dieta/veterinaria , Suplementos Dietéticos , Femenino , Carne/análisis
16.
Science ; 371(6527): 386-390, 2021 01 22.
Artículo en Inglés | MEDLINE | ID: mdl-33479150

RESUMEN

Convergent evolution provides insights into the selective drivers underlying evolutionary change. Snake venoms, with a direct genetic basis and clearly defined functional phenotype, provide a model system for exploring the repeated evolution of adaptations. While snakes use venom primarily for predation, and venom composition often reflects diet specificity, three lineages of cobras have independently evolved the ability to spit venom at adversaries. Using gene, protein, and functional analyses, we show that the three spitting lineages possess venoms characterized by an up-regulation of phospholipase A2 (PLA2) toxins, which potentiate the action of preexisting venom cytotoxins to activate mammalian sensory neurons and cause enhanced pain. These repeated independent changes provide a fascinating example of convergent evolution across multiple phenotypic levels driven by selection for defense.


Asunto(s)
Venenos Elapídicos/enzimología , Elapidae/clasificación , Elapidae/genética , Evolución Molecular , Fosfolipasas A2 Grupo IV/genética , Dolor , Células Receptoras Sensoriales/fisiología , Adaptación Biológica/genética , Animales , Venenos Elapídicos/genética , Filogenia , Células Receptoras Sensoriales/metabolismo
17.
Parasite Immunol ; 32(3): 202-8, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20398183

RESUMEN

Chagas heart disease (CHD), caused by Trypanosoma cruzi infection, is a significant cause of morbidity and mortality in South and Central America. Enalapril, an angiotensin converting enzyme (ACE) inhibitor, is an important drug used to ameliorate heart functional capacity and its remodelling in individuals presenting CHD. In this study, we evaluated the effects of enalapril on systemic and cardiac immune response during experimental acute CHD. C57BL/6 mice infected with 50 trypomastigote forms of T. cruzi (Colombian strain) were treated daily with enalapril (25 mg/kg) and, after 30 days, a reduction in seric levels of IFN-gamma, TNF-alpha, CCL5/RANTES and nitric oxide, but not in that of IL-10, was detected. This imbalance of cytokines reflects in a reduction of heart mononuclear infiltration and in an increasing of cardiac mast cells. Enalapril also presents a new and interesting in vitro and in vivo anti-T. cruzi activity probably acting on parasite oxidative pathway via cytochrome-P450. Our data show that enalapril exerts an important anti-T. cruzi and anti-inflammatory activity during acute CHD reducing inflammatory cells and, possibly, preventing fibrotic process in the chronic phase. Nevertheless, further studies are still necessary to clarify the mechanisms by which this drug is acting on the parasites and on the immune pathways.


Asunto(s)
Antiprotozoarios/administración & dosificación , Cardiomiopatía Chagásica/prevención & control , Enfermedad de Chagas/complicaciones , Enfermedad de Chagas/tratamiento farmacológico , Enalapril/administración & dosificación , Trypanosoma cruzi/efectos de los fármacos , Animales , Enfermedad de Chagas/inmunología , Enfermedad de Chagas/patología , Citocinas/sangre , Masculino , Ratones , Ratones Endogámicos C57BL , Óxido Nítrico/sangre , Suero/química
18.
Braz J Med Biol Res ; 53(12): e10279, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33111741

RESUMEN

Obesity affects the respiratory system through various mechanisms, including systemic inflammation and direct mechanical hindrance due to fat deposition in the chest and abdomen. In addition, changes in the neural control of respiration and increases in thoracic blood volume can promote abnormalities in lung function. Thus, determining relationships between the distance covered in the 6-min walk test (6MWT) and demographic and lung function variables may help us better understand the mechanisms involved in reduced functional exercise capacity in obesity. To explore the determinants of the 6-min walking distance (6MWD) and evaluate the influence of lung function on the distance covered, 263 obese Brazilian women performed the 6MWT and underwent spirometry and respiratory muscle strength measurement. The mean age was 41.8±11.1 years. The mean body mass index (BMI) was 45±8 kg/m2. The 6MWD showed correlations with height (r=0.319), age (r=-0.281), weight (r=-0.370), BMI (r=-0.561), forced vital capacity (FVC, r=0.443), expiratory peak flow (r=0.278), maximal inspiratory pressure (MIP, r=0.326), and maximal expiratory pressure (r=0.259), all with P<0.0001. In the stepwise forward regression analysis, BMI, FVC, age, and MIP were the independent predictive variables for 6MWD, explaining 41% of its variability. The reference equation including lung function was as follows: 6MWD (m) = 513.6 - (4.439 × BMIkg/m2) + (1.136 × FVC%predicted) - (1.048 × ageyrs) + (0.544 × MIP%predicted). Thus, the inclusion of lung function in a reference equation for 6MWD contributes to a better prediction of the distance covered in this population.


Asunto(s)
Obesidad/terapia , Adulto , Brasil , Diabetes Mellitus Tipo 2 , Tolerancia al Ejercicio , Femenino , Humanos , Pulmón , Persona de Mediana Edad , Prueba de Paso , Caminata
19.
Neotrop Entomol ; 49(6): 821-831, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32946024

RESUMEN

In the present study, we analyzed a unique phytophysiognomy in the Amazon region, which is formed by savanna-like vegetation on iron-rich soil (known locally as canga) located within an iron-ore mining region. We used the habitat template theory to test the hypothesis that changes in the physical-chemical properties of streams and the physical structure of their habitats at in-stream and micro-basin (landscape) levels affect the taxonomic and trophic composition of immature aquatic insects. For this, we used a local environmental matrix composed of nine physical-chemical and structural habitat variables, together with the Habitat Integrity Index. We also calculated landscape metrics based on the area of the micro-basin, such as relief, slope, mean current flow, and vegetation cover. We divided the aquatic insects into five functional feeding groups based on their diet and food sources. Our results indicate that changes in the trophic level of the insects of the orders Ephemeroptera, Plecoptera, and Trichoptera are more easily observed than the taxonomic structure of communities. The loss of environmental integrity and vegetation cover were responsible for 84% of the variation observed in the composition of functional feeding groups (FFGs). Our study shows that aquatic insect communities in the canga and in the Amazon regions dominated by forest require specific in-stream and landscape conditions. These findings reinforce the need for the preservation of areas of canga vegetation, which not only have a unique levels of biological diversity, but are also targeted for the exploitation of their economically valuable natural resources.


Asunto(s)
Biodiversidad , Insectos/clasificación , Ríos , Animales , Organismos Acuáticos/clasificación , Brasil , Bosques
20.
Br J Cancer ; 100(6): 881-7, 2009 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-19259089

RESUMEN

The objective of this study was to investigate the efficacy of first-line chemotherapy containing irinotecan and/or oxaliplatin in patients with advanced mucinous colorectal cancer. Prognostic factors associated with response rate and survival were identified using univariate and multivariate logistic and/or Cox proportional hazards analyses. The population included 255 patients, of whom 49 (19%) had mucinous and 206 (81%) had non-mucinous colorectal cancer. The overall response rates for mucinous and non-mucinous tumours were 18.4 (95% CI, 7.5-29.2%) and 49% (95% CI, 42.2-55.8%), respectively (P=0.0002). After a median follow-up of 45 months, median overall survival for the mucinous patients was 14.0 months compared with 23.4 months for the non-mucinous group (hazard ratio (HR), 1.74; CI 95%, 1.27-3.31; P=0.0034). After adjustment for significant features by multivariate Cox regression analysis, mucinous histology was associated with poor overall survival (HR, 1.593, 95% CI, 1.05-2.40; P=0.0267), together with performance status ECOG 2, number of metastatic sites > or =2, and peritoneal metastases. This retrospective analysis shows that patients with mucinous colorectal cancer have poor responsiveness to oxaliplatin/irinotecan-based first-line combination chemotherapy and an unfavourable prognosis compared with non-mucinous colorectal cancer patients.


Asunto(s)
Adenocarcinoma Mucinoso/tratamiento farmacológico , Antineoplásicos/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Camptotecina/análogos & derivados , Neoplasias Colorrectales/tratamiento farmacológico , Compuestos Organoplatinos/administración & dosificación , Adenocarcinoma Mucinoso/genética , Adenocarcinoma Mucinoso/mortalidad , Adenocarcinoma Mucinoso/patología , Adulto , Anciano , Anciano de 80 o más Años , Camptotecina/administración & dosificación , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Femenino , Humanos , Irinotecán , Masculino , Inestabilidad de Microsatélites , Persona de Mediana Edad , Oxaliplatino , Estudios Retrospectivos
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