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1.
J Anim Physiol Anim Nutr (Berl) ; 102(1): e460-e467, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28983986

RESUMEN

The aim of this study was to evaluate the effect of the level of alfalfa in the diet on feed intake and digestibility of two types of rabbits, wild (Oryctolagus cuniculus algirus) vs. domestic (O. cuniculus cuniculus). Ten wild (W; mean LW = 927 g) and 10 domestic (D; mean LW = 4,645 g) adult rabbit does were fed ad libitum two pelleted diets: a control diet (C) with 15% of dehydrated alfalfa hay (as feed basis) and a test diet (A) with 36% of dehydrated alfalfa hay (as feed basis), according to a change-over design. Wild does dry matter (DM) intake per kg live weight (BW) was 55% higher (p < .001) than the intake of the D ones (58 g vs. 37 g DM per kg BW respectively). However, no difference (p > .05) was found when intake was expressed per kg0.75 BW (ca. 56 g DM) and tended to be higher (p = .07) in D does when expressed per kg0.67 BW (62 g vs. 55 g DM). Domestic does showed a higher (p < .05) DM, organic matter, crude energy and neutral detergent fibre digestibility (3; 2; 3; 3 percentage points respectively) than W does. The amount of nutrients and energy digested by D does was lower per kg BW (p < .001), similar per kg0.75 BW (p > .05) and tended to be higher per kg0.67 BW (p < .1) than in W does. The diet content of alfalfa did not affect (p > .05) the feed intake nor the diet digestibility. This study suggests that W rabbits exhibit a higher intake per kg BW and a lower digestibility than their D counterparts, which results in similar digestible nutrient and energy intake per kg BW powered to 0.75. The nutritive value of dehydrated alfalfa for rabbits, evaluated through intake and digestibility, seems to be equivalent to their base diets (forage plus concentrate).


Asunto(s)
Alimentación Animal/análisis , Animales Domésticos , Animales Salvajes , Dieta/veterinaria , Medicago sativa , Conejos/genética , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Digestión/fisiología , Conducta Alimentaria , Femenino , Conejos/fisiología
2.
Braz J Biol ; 83: e273473, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38126629

RESUMEN

Guavira (Campomanesia adamantium, Myrtaceae) is a native fruit from the Brazilian Cerrado savanna and is socio-economically important for the indigenous and traditional people living in the Central-West. This is a bibliographic review of the biological properties of guavira and its derivatives, and, after discussing experimental studies, an interdisciplinary approach is conducted highlighting the im-portance of Agroforestry Systems as an ecological restoration tool to leverage the production chain of guavira while providing ecosystem services. Many research groups studied effects of polyphenols and other bioactive compounds and biological properties of this fruit and other plant parts such as antibiotic, antioxidant, anti-inflammatory, anti-hyperlipidemic, anti-diarrheic and antitumoral activities, cardiovascular and hepatic protection and action against neuropathic pain. Besides, guavira by-products benefit poultry intestinal health, similarly to antibiotics added to their feed. Furthermore, several biotechnological products were found, like pulp flour, seasoning from the peel, sunscreen, and seed oil similar to olive oil with pharmaceutical and industrial potential. We conclude by emphasizing the importance of guavira for restoration and preservation of the threatened Brazilian Cerrado, and for the socio-environmental development of family agriculture. The same approach and study are welcome and necessary in other regions and domains worldwide having their native flora as means for a restorative end.


Asunto(s)
Myrtaceae , Extractos Vegetales , Ecosistema , Frutas/química , Myrtaceae/química , Extractos Vegetales/farmacología , Semillas/química
3.
Braz J Biol ; 83: e275582, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38055505

RESUMEN

Potential breeding containers for Aedes aegypti and Aedes albopictus mosquitoes are found in different environments, these places are considered by the National Dengue Control Program in Brazil as strategic points (SP), which have favorable conditions for the development of those insects. The aim of this study is to identify potential breeding containers for A. aegypti and A. albopictus at strategic points in the city of Codó, Maranhão. This study was conducted in five districts, one in each administrative area of the city. A survey of the types and quantity of existing strategic points in each neighborhood was carried out, and surveys of these properties were carried out to inspect the potential breeding containers, with the collection of the vectors' number of immatures found at them. 125 properties were inspected of which 76.91% and 81.25% were vacant lots in the dry and rainy seasons, respectively. There was a difference between the median of the different strategic points (H = 21.96; p < 0.0001), For A. aegypti, there was no difference between the medians of number of immatures regarding the strategic points (H = 3.71; p = 0.28). The total number of immature A. albopictus was higher in vacant lots than in workshops (H = 9.41; p = 0.02, p < 0.05). 4,356 and 4,911 potential breeding containers were found in the dry and rainy seasons, respectively. Regarding the potential breeding containers, 7 (0.16%) and 47 (0.96%) were found with immature vectors, in the dry and rainy seasons, respectively. There were more positive containers in the rainy season for which there was a difference between the median of the number of mosquitoes per positive container (H = 15.66; p = 0.01), the number of immatures for the tires group was greater than Vases and Fixed groups (p < 0.05); the same result was observed in the analyses of the species in the separate form. The impressive number of potential breeding containers found in the SP in both seasons highlights the importance of developing control strategies for these vectors, with emphasis on places such as vacant lots, workshops, tire shops and junkyards, which are serving as dispersal urban sites of vectors.


Asunto(s)
Aedes , Animales , Brasil , Ciudades , Estaciones del Año , Larva
4.
Methods Mol Biol ; 2461: 43-66, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35727443

RESUMEN

Protein engineering through directed evolutison is facilitated by the screening and characterization of protein libraries. Efficient and effective methods for multiple site-saturation mutagenesis, such as Darwin Assembly, can accelerate the sampling of relevant sequence space and the identification of variants with desired functionalities. Here, we present the automation of the Darwin Assembly method, using a Gilson PIPETMAX™ liquid handling platform under the control of the Antha software platform, which resulted in the accelerated construction of complex, multiplexed gene libraries error-free and with minimal hands-on time, while maintaining flexibility over experimental parameters through a graphical user interface rather than requiring user-driven library-dependent programming of the liquid handling platform. We also present an approach for barcoding libraries that overcomes amplicon length limitations in next generation sequencing and enables fast reconstruction of library reads.


Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento , Programas Informáticos , Automatización/métodos , Biblioteca de Genes , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Ingeniería de Proteínas/métodos
5.
Braz J Biol ; 82: e261840, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35894350

RESUMEN

The influence of abiotic factors on the abundance of microorganism populations in soil has been sparsely studied, especially regarding Bacillus thuringiensis (Bt) bacteria. Therefore, this research was aimed at analyzing the relationship between the chemical and textural characteristics of the soil of the Cerrado (savanna) of Maranhão State on the abundance of Bacillus thuringiensis. Soil samples were collected in different municipalities in eastern Maranhão: São Mateus do Maranhão, Alto Alegre, Coroatá, Timbiras and Codó. The soil samples were obtained in the 0-0.1 m layer for soil fertility and texture analysis. Then, in the same area for the isolation of Bt, 1 g of soil was collected. The colonies obtained in the isolation that featured morphological characteristics of Bacillus spp. were visualized under phase contrast microscopy. Principal component analysis, clustering and correlations were peformed. Results: The sand content correlated positively with the Bacillus thuringiensis index (iBt). The cluster analysis allowed for verifying that the soils not showed iBt in function of high concentrations of aluminum (Al) and potential acidity (H+Al). Considering as these attributes (Al and H+Al) alter the availability of P in the soil, the abundance of Bacillus thuringiensis may have been impaired by the deficiency of this element in the environment. Conclusion: Bt has correlations with soil texture, and high concentrations of aluminum and potential acidity in the soil influencing the permanence of Bacillus thuringiensis in Maranhão eastern Cerrado.


Asunto(s)
Bacillus , Suelo , Aluminio , Brasil , Suelo/química
6.
Theriogenology ; 182: 71-77, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35131675

RESUMEN

Final antral follicle development and future ovulation are mediated by gonadotropin-induced changes with spatio-temporally regulated expression of genes. Here, we aimed to quantify the relative mRNA abundance of bta-miR-222 and its predicted target, LHCGR, in granulosa cells (GCs) from follicles, after follicle deviation, as well as from GCs cultured in vitro with follicle stimulating hormone (FSH) and/or insulin. Thus, to study the impact of follicle deviation, Nelore heifers (n = 10; Bos taurus indicus) were hormonally synchronized and slaughtered 3 days after ovulation. Then, GCs from the dominant follicle (DF) and its respective subordinate follicle (SF) were recovered for RT-qPCR. For in vitro analysis, small follicles (2-5 mm) were dissected from bovine ovaries collected from a local abattoir. The GCs were isolated and cultured in serum-free medium, or treated with insulin (1 ng/mL or 10 ng/mL) alone or in combination with human recombinant FSH (1 ng/mL), for 6 days. Our findings showed that the relative mRNA abundance of LHCGR in GCs was higher in the DF compared to the SF (p = 0.01). Inversely, bta-miR-222 expression was lower in the DF compared to the SF (p = 0.01). Furthermore, GCs cultured with FSH and insulin together resulted in a higher abundance of LHCGR and a lower abundance of bta-miR-222 (p ≤ 0.05) when compared to GCs cultured with insulin alone. In conclusion, we found that the LHCGR upregulation in GCs from the DF is inversely related to bta-miR-222 expression. We also suggest the involvement of FSH in bta-miR-222 suppression in healthy bovine GCs.


Asunto(s)
Hormona Folículo Estimulante , MicroARNs , Animales , Bovinos , Células Cultivadas , Femenino , Hormona Folículo Estimulante/metabolismo , Hormona Folículo Estimulante/farmacología , Células de la Granulosa/metabolismo , Insulina/metabolismo , Insulina/farmacología , MicroARNs/genética , MicroARNs/metabolismo , Folículo Ovárico
7.
Braz J Biol ; 84: e257402, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35081217

RESUMEN

Visceral leishmaniasis (VL) is an infectious disease predominant in countries located in the tropics. The prediction of occurrence of infectious diseases through epidemiologic modeling has revealed to be an important tool in the understanding of its occurrence dynamic. The objective of this study was to develop a forecasting model for the incidence of VL in Maranhão using the Seasonal Autoregressive Integrated Moving Average model (SARIMA). We collected monthly data regarding VL cases from the National Disease Notification System (SINAN) corresponding to the period between 2001 and 2018. The Box-Jenkins method was applied in order to adjust a SARIMA prediction model for VL general incidence and by sex (male or female) for the period between January 2019 and December 2013. For 216 months of this time series, 10,431 cases of VL were notified in Maranhão, with an average of 579 cases per year. With regard to age range, there was a higher incidence among the pediatric public (0 to 14 years of age). There was a predominance in male cases, 6437 (61.71%). The Box-Pierce test figures for overall, male and female genders supported by the results of the Ljung-Box test suggest that the autocorrelations of residual values act as white noise. Regarding monthly occurrences in general and by gender, the SARIMA models (2,0,0) (2,0,0), (0,1,1) (0,1,1) and (0,1,1) (2, 0, 0) were the ones that mostly adjusted to the data respectively. The model SARIMA has proven to be an adequate tool for predicting and analyzing the trends in VL incidence in Maranhão. The time variation determination and its prediction are decisive in providing guidance in health measure intervention.


Asunto(s)
Leishmaniasis Visceral , Adolescente , Brasil/epidemiología , Niño , Preescolar , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Leishmaniasis Visceral/diagnóstico , Leishmaniasis Visceral/epidemiología , Masculino , Modelos Estadísticos , Estaciones del Año
8.
Braz J Biol ; 81(4): 872-880, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33053121

RESUMEN

Bacillus thuringiensis is the most commonly used entomopathogen in the control of Aedes aegypti, which is a vector for different etiological agents that cause serious infections in humans. Several studies aim to isolate strains of this bacterium from different environments, with the perspective of selecting isolates with larvicidal activity for mosquitoes. Aiming at the insecticidal action of B. thuringiensis, the present study aimed to prospect B. thuringiensis of restinga and mangrove soils from the state of Maranhão, Brazil, with toxic potential for use in the biological control of Ae. aegypti. Bioassays were performed to determine the entomopathogenic activity of the bacilli against Ae. aegypti and lethal concentrations (LC50 and CL90) were estimated after the tests. Polymerase Chain Reaction and SDS-PAGE techniques were performed to verify the gene and protein content of the isolates, respectively. The soil of the mangrove and restinga ecosystems showed potential for obtaining B. thuringiensis. This isolate, in addition to having proteins with molecular mass similar to the toxins Cry and Cyt, also presented several diptera-specific genes cry and cyt, demonstrating that it has high potential to be used in the biological control of Ae. aegypti.


Asunto(s)
Aedes , Bacillus thuringiensis , Animales , Bacillus thuringiensis/genética , Brasil , Ecosistema , Humanos , Larva , Mosquitos Vectores , Control Biológico de Vectores
9.
Braz J Biol ; 81(1): 114-124, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32130286

RESUMEN

Entomopathogenic agents are viable and effective options due to their selective action against insects but benign effects on humans and the environment. The most promising entomopathogens include subspecies of Bacillus thuringiensis (Bt), which are widely used for the biological control of insects, including mosquito vectors of human pathogens. The efficacy of B. thuringiensis toxicity has led to the search for new potentially toxic isolates in different regions of the world. Therefore, soil samples from the Amazon, Cerrado and Caatinga biomes of the state of Maranhão were evaluated for their potential larvicidal action against Aedes aegypti. The isolates with high toxicity to mosquito larvae, as detected by bioassays, were subjected to histological evaluation under a light microscope to identify the genes potentially responsible for the toxicity. Additionally, the toxic effects of these isolates on the intestinal epithelium were assessed. In the new B. thuringiensis isolates toxic to A. aegypti larvae, cry and cyt genes were amplified at different frequencies, with cry4, cyt1, cry32, cry10 and cry11 being the most frequent (33-55%) among those investigated. These genes encode specific proteins toxic to dipterans and may explain the severe morphological changes in the intestine of A. aegypti larvae caused by the toxins of the isolates.


Asunto(s)
Aedes , Bacillus thuringiensis , Culicidae , Insecticidas , Animales , Bacillus thuringiensis/genética , Ecosistema , Humanos , Larva , Mosquitos Vectores , Control Biológico de Vectores
10.
Braz J Biol ; 81(3): 557-565, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32876165

RESUMEN

Cutaneous leishmaniasis (CL) is a neglected tropical disease with a wide distribution in the Americas. Brazil is an endemic country and present cases in all states. This study aimed to describe the occurrence, the underlying clinical and epidemiological factors, and the correlation of climatic variables with the frequency of reported CL cases in the municipality of Caxias, state of Maranhão, Brazil. This is a retrospective and descriptive epidemiological study based on data extracted from the Brazilian Information System of Diseases Notification, from 2007 to 2017. Maximum and minimum temperature, precipitation, and relative air humidity data were provided by the Brazilian National Institute of Meteorology. A total of 201 reported autochthonous CL cases were analyzed. The predominance of cases was observed in males (70.1%). The age range between 31 and 60 years old was the most affected, with 96 cases (47.9%). Of the total number of registered cases, 38.8% of the affected individuals were engaged in agriculture-related activities. The georeferenced distribution revealed the heterogeneity of disease occurrence, with cases concentrated in the Western and Southern regions of the municipality. An association was detected between relative air humidity (monthly mean) and the number of CL cases per month (p = 0.04). CL continues to be a concerning public health issue in Caxias. In this context, there is a pressing need to strengthen measures of prevention and control of the disease through the network of health services of the municipality, considering local and regional particularities.


Asunto(s)
Leishmaniasis Cutánea , Adulto , Brasil/epidemiología , Ciudades , Ambiente , Humanos , Leishmaniasis Cutánea/epidemiología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
11.
Reprod Domest Anim ; 45(5): 881-7, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19392666

RESUMEN

The study evaluated, in early post-partum anoestrous Nelore cows, if the increase in plasma oestradiol (E2) concentrations in the pre-ovulatory period and/or progesterone priming (P4 priming) preceding ovulation, induced by hormonal treatment, reduces the endogenous release of prostaglandin PGF(2)α and prevents premature lysis of the corpus luteum (CL). Nelore cows were subjected to temporary calf removal for 48 h and divided into two groups: GPE/eCG group (n = 10) and GPG/eCG group (n = 10). Animals of the GPE/eCG group were treated with a GnRH agonist. Seven days later, they received 400 IU of eCG, immediately after PGF(2)α treatment, and on day 0, 1.0 mg of oestradiol benzoate (EB). Cows of the GPG/eCG group were similarly treated as those of the GPE/eCG group, except that EB was replaced with a second dose of GnRH. All animals were challenged with oxytocin (OT) 9, 12, 15 and 18 days after EB or GnRH administration and blood samples were collected before and 30 min after OT. Irrespective of the treatments, a decline in P4 concentration on day 18 was observed for cows without P4 priming. However, animals exposed to P4 priming, treated with EB maintained high P4 concentrations (8.8 ± 1.2 ng/ml), whereas there was a decline in P4 on day 18 (2.1 ± 1.0 ng/ml) for cows that received GnRH to induce ovulation (p < 0.01). Production of 13,14-dihydro-15-keto prostaglandin F(2)α (PGFM) in response to OT increased between days 9 and 18 (p < 0.01), and this increase tended to be more evident in animals not exposed to P4 priming (p < 0.06). In conclusion, the increase in E2 during the pre-ovulatory period was not effective in inhibiting PGFM release, which was lower in P4-primed than in non-primed animals. Treatment with EB promoted the maintenance of elevated P4 concentrations 18 days after ovulation in P4-primed animals, indicating a possible beneficial effect of hormone protocols containing EB in animals with P4 priming.


Asunto(s)
Bovinos/fisiología , Dinoprost/análogos & derivados , Fármacos para la Fertilidad Femenina/farmacología , Oxitocina/farmacología , Progesterona/farmacología , Animales , Dinoprost/metabolismo , Femenino , Fármacos para la Fertilidad Femenina/administración & dosificación , Ovulación/efectos de los fármacos , Periodo Posparto
12.
Poult Sci ; 89(11): 2494-8, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20952714

RESUMEN

Red-legged partridge breeders are frequently reared in captivity with the aim of producing fertile eggs and chicks. However, little is known regarding the role of breeder age on fertility and egg production performance. Therefore, we investigated the effects of breeder age on egg size and shape, flock reproductive performance, fertility, hatchability, and embryonic mortality. In experiment 1, the effects of breeders' age on fertility, hatchability of eggs, and embryo mortality were evaluated. We found that partridge breeder age significantly affected the onset of egg laying, egg production, number and proportion of settable eggs, hatchability, and fertility. Specifically, 1-yr-old females laid their first egg 1 wk later than 2, 3, or 4-yr-old birds. Furthermore, 2-yr-old females produced a significantly higher number of settable and fertile eggs than other females (53.0 vs. 46.4 to 48.5) and had a lower incidence of embryo mortality. In experiment 2, we examined the effects of breeder age, egg size, and egg shape on egg hatchability. We found that small eggs (<17.6 g) had a significantly lower hatchability than medium (17.6 to 18.9 g) or large eggs (>18.9 g). However, we did not observe any significant correlation between egg shape and hatchability. These results suggest that red-legged partridge breeders attain maximum reproductive capacity at 2 yr of age and produce fewer eggs with lower weight and hatchability thereafter.


Asunto(s)
Galliformes/fisiología , Oviposición/fisiología , Óvulo/fisiología , Envejecimiento/fisiología , Animales , Embrión no Mamífero/fisiología , Femenino , Galliformes/crecimiento & desarrollo , Óvulo/crecimiento & desarrollo , Portugal , Reproducción/fisiología
13.
Theriogenology ; 71(3): 519-24, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18849065

RESUMEN

The objective was to evaluate the effects of temporary calf removal (TCR), eCG administration, or both, in a progesterone-based protocol. Suckled Nellore cows (40-80 d postpartum, n=443) with body condition scores from 2.0 to 3.5 (5-point scale) on three farms were all given a synchronizing protocol (PEPE). At the start (designated Day 0), cows were given an intravaginal device (1.0 g of progesterone) and 2.5mg of estradiol benzoate (EB) im. On Day 8, the device was removed and cows were given PGF(2 alpha) (150 microg of D-cloprostenol im), followed in 24h by 1.0mg EB im, and 30-36 h thereafter, fixed-time AI. The design was a 2 x 2 factorial; main effects were TCR (54-60 h; from device removal to FTAI) and eCG treatment (300 IU im, concurrent with PGF(2 alpha)). Transrectal ultrasonography was done on Days -10 and 0 to detect anestrus (absence of a CL at both examinations) and approximately 30 d after FTAI (pregnancy diagnosis). Data were analyzed by logistic regression. The following variables did not significantly affect pregnancy rates: farm, postpartum interval, cyclicity, inseminators, and semen (sire). Overall, 77% of the cows were deemed anestrus. Pregnancy rates were similar (P>0.05) among treatment groups: Control (54/108=50.0%), TCR (44/106=41.5%), eCG (63/116=54.3%), and TCR+eCG (49/113=43.4%). Pregnancy rate was higher in multiparous than primiparous cows (186/360, 51.7% vs. 24/83, 28.9%, P<0.01), but was not significantly affected by cyclicity status or body condition score. In conclusion, temporary calf removal, eCG, or both, did not significantly increase pregnancy rate to timed-insemination in a progesterone-based synchronization protocol in postpartum Nellore cows with acceptable body condition.


Asunto(s)
Bovinos , Gonadotropina Coriónica/farmacología , Inseminación Artificial/veterinaria , Lactancia/fisiología , Progesterona/farmacología , Administración Intravaginal , Animales , Animales Lactantes , Dinoprost/farmacología , Estradiol/administración & dosificación , Estradiol/análogos & derivados , Estradiol/farmacología , Sincronización del Estro/efectos de los fármacos , Femenino , Fármacos para la Fertilidad Femenina/administración & dosificación , Fármacos para la Fertilidad Femenina/farmacología , Periodo Posparto , Embarazo , Progesterona/administración & dosificación
14.
Meat Sci ; 81(2): 357-63, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22064175

RESUMEN

Sixty nine growing rabbits were scanned over the lumbar region using a real time ultrasonography (RTU) machine to estimate loin muscularity and carcass composition. Longissimus thoracis et lumborum muscle (LM) depth, width and area were taken. Animals were weighed (LW), slaughtered and carcass composition was determined. Equivalent measurements to those taken by RTU in vivo were taken on the carcass and muscularity indices were calculated on carcass and in vivo. Simple correlations between the two types of measurements were determined and carcass composition was estimated by simple and multiple regressions. The LW varied from 1200 to 3410g. The simple correlations between carcass and in vivo RTU LM measurements were high (P<0.001) and the LM area was the trait with the highest correlation (r=0.92). Simple correlations between muscularity indices measured by RTU and in carcass were significant (P<0.001). In vivo RTU measurements explained a large amount of the variation of the carcass meat weight (MW) and bone weight (r(2) range from 0.49 to 0.77; P<0.001). Using multiple regression equations to estimate carcass composition, the best fit was obtained with the LW and one or more in vivo RTU measurement. The LW explained 90.6% of the variation of MW in the carcass. In vivo RTU is able to estimate loin muscularity and carcass composition of rabbits with accuracy. The usefulness of in vivo RTU and LW to predict carcass composition of rabbits using multiple regressions was also shown.

15.
Braz. j. biol ; 84: e257402, 2024. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1355856

RESUMEN

Abstract Visceral leishmaniasis (VL) is an infectious disease predominant in countries located in the tropics. The prediction of occurrence of infectious diseases through epidemiologic modeling has revealed to be an important tool in the understanding of its occurrence dynamic. The objective of this study was to develop a forecasting model for the incidence of VL in Maranhão using the Seasonal Autoregressive Integrated Moving Average model (SARIMA). We collected monthly data regarding VL cases from the National Disease Notification System (SINAN) corresponding to the period between 2001 and 2018. The Box-Jenkins method was applied in order to adjust a SARIMA prediction model for VL general incidence and by sex (male or female) for the period between January 2019 and December 2013. For 216 months of this time series, 10,431 cases of VL were notified in Maranhão, with an average of 579 cases per year. With regard to age range, there was a higher incidence among the pediatric public (0 to 14 years of age). There was a predominance in male cases, 6437 (61.71%). The Box-Pierce test figures for overall, male and female genders supported by the results of the Ljung-Box test suggest that the autocorrelations of residual values act as white noise. Regarding monthly occurrences in general and by gender, the SARIMA models (2,0,0) (2,0,0), (0,1,1) (0,1,1) and (0,1,1) (2, 0, 0) were the ones that mostly adjusted to the data respectively. The model SARIMA has proven to be an adequate tool for predicting and analyzing the trends in VL incidence in Maranhão. The time variation determination and its prediction are decisive in providing guidance in health measure intervention.


Resumo A leishmaniose visceral (LV) é uma doença de natureza infecciosa, predominante em países de zonas tropicais. A predição de ocorrência de doenças infecciosas através da modelagem epidemiológica tem se revelado uma importante ferramenta no entendimento de sua dinâmica de ocorrência. O objetivo deste estudo foi desenvolver um modelo de previsão da incidência da LV no Maranhão usando o modelo de Média Móvel Integrada Autocorrelacionada Sazonal (SARIMA). Foram coletados os dados mensais de casos de LV através do Sistema de Informação de Agravos de Notificação (SINAN) correspondentes ao período de 2001 a 2018. O método de Box-Jenkins foi aplicado para ajustar um modelo de predição SARIMA para incidência geral e por sexo (masculino e feminino) de LV para o período de janeiro de 2019 a dezembro de 2023. Durante o período de 216 meses dessa série temporal, foram registrados 10.431 casos de LV no Maranhão, com uma média de 579 casos por ano. Em relação à faixa etária, houve maior registro no público pediátrico (0 a 14 anos). Houve predominância do sexo masculino, com 6437 casos (61,71%). Os valores do teste de Box-Pierce para incidência geral, sexo masculino e feminino reforçados pelos resultados do teste Ljung-Box sugerem que as autocorrelações de resíduos apresentam um comportamento de ruído branco. Para incidência mensal geral e por sexo masculino e feminino, os modelos SARIMA (2,0,0) (2,0,0), (0,1,1) (0,1,1) e (0,1,1) (2, 0, 0) foram os que mais se ajustaram aos dados, respectivamente. O modelo SARIMA se mostrou uma ferramenta adequada de previsão e análise da tendência de incidência da LV no Maranhão. A determinação da variação temporal e sua predição são determinantes no norteamento de medidas de intervenção em saúde.


Asunto(s)
Humanos , Masculino , Femenino , Recién Nacido , Lactante , Preescolar , Niño , Adolescente , Leishmaniasis Visceral/diagnóstico , Leishmaniasis Visceral/epidemiología , Estaciones del Año , Brasil/epidemiología , Incidencia , Modelos Estadísticos
16.
Braz. j. biol ; 842024.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469328

RESUMEN

Abstract Visceral leishmaniasis (VL) is an infectious disease predominant in countries located in the tropics. The prediction of occurrence of infectious diseases through epidemiologic modeling has revealed to be an important tool in the understanding of its occurrence dynamic. The objective of this study was to develop a forecasting model for the incidence of VL in Maranhão using the Seasonal Autoregressive Integrated Moving Average model (SARIMA). We collected monthly data regarding VL cases from the National Disease Notification System (SINAN) corresponding to the period between 2001 and 2018. The Box-Jenkins method was applied in order to adjust a SARIMA prediction model for VL general incidence and by sex (male or female) for the period between January 2019 and December 2013. For 216 months of this time series, 10,431 cases of VL were notified in Maranhão, with an average of 579 cases per year. With regard to age range, there was a higher incidence among the pediatric public (0 to 14 years of age). There was a predominance in male cases, 6437 (61.71%). The Box-Pierce test figures for overall, male and female genders supported by the results of the Ljung-Box test suggest that the autocorrelations of residual values act as white noise. Regarding monthly occurrences in general and by gender, the SARIMA models (2,0,0) (2,0,0), (0,1,1) (0,1,1) and (0,1,1) (2, 0, 0) were the ones that mostly adjusted to the data respectively. The model SARIMA has proven to be an adequate tool for predicting and analyzing the trends in VL incidence in Maranhão. The time variation determination and its prediction are decisive in providing guidance in health measure intervention.


Resumo A leishmaniose visceral (LV) é uma doença de natureza infecciosa, predominante em países de zonas tropicais. A predição de ocorrência de doenças infecciosas através da modelagem epidemiológica tem se revelado uma importante ferramenta no entendimento de sua dinâmica de ocorrência. O objetivo deste estudo foi desenvolver um modelo de previsão da incidência da LV no Maranhão usando o modelo de Média Móvel Integrada Autocorrelacionada Sazonal (SARIMA). Foram coletados os dados mensais de casos de LV através do Sistema de Informação de Agravos de Notificação (SINAN) correspondentes ao período de 2001 a 2018. O método de Box-Jenkins foi aplicado para ajustar um modelo de predição SARIMA para incidência geral e por sexo (masculino e feminino) de LV para o período de janeiro de 2019 a dezembro de 2023. Durante o período de 216 meses dessa série temporal, foram registrados 10.431 casos de LV no Maranhão, com uma média de 579 casos por ano. Em relação à faixa etária, houve maior registro no público pediátrico (0 a 14 anos). Houve predominância do sexo masculino, com 6437 casos (61,71%). Os valores do teste de Box-Pierce para incidência geral, sexo masculino e feminino reforçados pelos resultados do teste Ljung-Box sugerem que as autocorrelações de resíduos apresentam um comportamento de ruído branco. Para incidência mensal geral e por sexo masculino e feminino, os modelos SARIMA (2,0,0) (2,0,0), (0,1,1) (0,1,1) e (0,1,1) (2, 0, 0) foram os que mais se ajustaram aos dados, respectivamente. O modelo SARIMA se mostrou uma ferramenta adequada de previsão e análise da tendência de incidência da LV no Maranhão. A determinação da variação temporal e sua predição são determinantes no norteamento de medidas de intervenção em saúde.

17.
Poult Sci ; 87(4): 733-43, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18339996

RESUMEN

Some feedstuffs containing significant levels of fiber may be a good source of bioactive compounds that may contribute to improving broiler meat quality. However, high fiber level can have a negative impact on broiler performance. A study was undertaken to investigate the impact of incorporating citrus pulp (5 or 10%) or dehydrated pasture (5 or 10%) on the performance, carcass yield, and characteristics of broiler chickens. A diet containing neither citrus pulp nor dehydrated pasture was used as control. The results on growth performances showed that daily weight gain was reduced by 26% in birds of the 10% citrus pulp treatment (P<0.05). Compared with the control treatment, increases in feed intake occurred in birds consuming diets with 5 or 10% citrus pulp, which resulted in significantly higher feed conversion rates with the 10% level. Under the same incorporation rate, dehydrated pasture had effects less evident on the performances of broiler chicken. In addition, diets containing citrus pulp, displaying higher percentages of soluble nonstarch polysaccharides, increased small intestine relative length, and reduced carcass yield. Inclusion of 10% dehydrated pasture in diets resulted in improved breast skin yellowness (P<0.05). Finally, the results revealed that incorporation of the nonstarch polysaccharide-rich feedstuffs had a major impact on the fatty acid profile (affected 16 of 21 fatty acids) of broiler meat. Polyunsaturated fatty acids content in meat was higher in birds consuming the highest levels of both citrus pulp and dehydrated pasture, leading to increased ratios of polyunsaturated to saturated fatty acids. Together, the results suggest that incorporation of moderate levels of dehydrated pastures in poultry diets has a minor impact on broiler performance and can contribute significantly to improve breast skin yellowness and fatty acid composition of meat.


Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales , Pollos/fisiología , Citrus , Carne/análisis , Poaceae , Animales , Peso Corporal/fisiología , Pollos/crecimiento & desarrollo , Pollos/metabolismo , Colesterol/análisis , Ácidos Grasos no Esterificados/análisis , Lípidos/análisis , Carne/normas , Tamaño de los Órganos/fisiología , Distribución Aleatoria , Tocoferoles/análisis , Tocotrienoles/análisis
18.
Comput Biol Med ; 89: 520-529, 2017 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-28318505

RESUMEN

We propose a methodology to predict the cardiac epicardial and mediastinal fat volumes in computed tomography images using regression algorithms. The obtained results indicate that it is feasible to predict these fats with a high degree of correlation, thus alleviating the requirement for manual or automatic segmentation of both fat volumes. Instead, segmenting just one of them suffices, while the volume of the other may be predicted fairly precisely. The correlation coefficient obtained by the Rotation Forest algorithm using MLP Regressor for predicting the mediastinal fat based on the epicardial fat was 0.9876, with a relative absolute error of 14.4% and a root relative squared error of 15.7%. The best correlation coefficient obtained in the prediction of the epicardial fat based on the mediastinal was 0.9683 with a relative absolute error of 19.6% and a relative squared error of 24.9%. Moreover, we analysed the feasibility of using linear regressors, which provide an intuitive interpretation of the underlying approximations. In this case, the obtained correlation coefficient was 0.9534 for predicting the mediastinal fat based on the epicardial, with a relative absolute error of 31.6% and a root relative squared error of 30.1%. On the prediction of the epicardial fat based on the mediastinal fat, the correlation coefficient was 0.8531, with a relative absolute error of 50.43% and a root relative squared error of 52.06%. In summary, it is possible to speed up general medical analyses and some segmentation and quantification methods that are currently employed in the state-of-the-art by using this prediction approach, which consequently reduces costs and therefore enables preventive treatments that may lead to a reduction of health problems.


Asunto(s)
Tejido Adiposo/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador , Aprendizaje Automático , Mediastino/diagnóstico por imagen , Pericardio/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Femenino , Humanos , Masculino
19.
Braz J Biol ; 77(2): 396-401, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-27533732

RESUMEN

The viability of Aedes aegypti eggs was assessed in the Amazon region. The eggs were maintained under different conditions: indoors (insectarium) and outdoors (natural environment), as well as in different storage types (plastic cup, paper envelope, plastic bag) for different days. Egg viability was measured as the mean of hatchings observed from egg-bearing sheets of filter paper immersed in water, using three sheets randomly selected from each storage type and at both sites. There were significant differences in the viability of Ae. aegypti eggs with respect to the location (F=30.40; DF=1; P<0.0001), storage type (F=17.66; DF=2; P<0.0001), and time of storage (F=49.56; DF=9; P<0.0001). The interaction between storage site versus storage type was also significant (F=15.96; DF=2; P<0.0001). A higher hatching mean was observed for the eggs kept in the insectarium than for those outdoors (32.38 versus 7.46). Hatching rates of egg batches stored for 12 to 61 days ranged between 84 and 90%. A reduction was observed between 89 and 118 days, with values of 63 and 48%, respectively. With respect to type of storage, mean egg hatching was higher for the eggs in plastic cups (44.46). It was concluded that the viability of the eggs of Ae. aegypti in the Amazon region remains high up to 4 months, after which it declines drastically, although in this study hatching occurred for up to 8 months in very low percentages.


Asunto(s)
Aedes/fisiología , Ambiente , Aedes/crecimiento & desarrollo , Animales , Brasil , Óvulo/fisiología , Estaciones del Año , Manejo de Especímenes
20.
Braz. j. biol ; 81(4): 872-880, Oct.-Dec. 2021. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1153450

RESUMEN

Abstract Bacillus thuringiensis is the most commonly used entomopathogen in the control of Aedes aegypti, which is a vector for different etiological agents that cause serious infections in humans. Several studies aim to isolate strains of this bacterium from different environments, with the perspective of selecting isolates with larvicidal activity for mosquitoes. Aiming at the insecticidal action of B. thuringiensis, the present study aimed to prospect B. thuringiensis of restinga and mangrove soils from the state of Maranhão, Brazil, with toxic potential for use in the biological control of Ae. aegypti. Bioassays were performed to determine the entomopathogenic activity of the bacilli against Ae. aegypti and lethal concentrations (LC50 and CL90) were estimated after the tests. Polymerase Chain Reaction and SDS-PAGE techniques were performed to verify the gene and protein content of the isolates, respectively. The soil of the mangrove and restinga ecosystems showed potential for obtaining B. thuringiensis. This isolate, in addition to having proteins with molecular mass similar to the toxins Cry and Cyt, also presented several diptera-specific genes cry and cyt, demonstrating that it has high potential to be used in the biological control of Ae. aegypti.


Resumo Bacillus thuringiensis é o entomopatógeno mais utilizado no controle do Aedes aegypti, vetor de diferentes agentes etiológicos que causam infecções graves em humanos. Diversos estudos têm como objetivo isolar cepas dessa bactéria de diferentes ambientes, com a perspectiva de selecionar isolados com atividade larvicida para mosquitos. Visando a ação inseticida de B. thuringiensis, o presente estudo teve como objetivo prospectar B. thuringiensis de solos de restinga e mangue do estado do Maranhão, Brasil, com potencial tóxico para uso no controle biológico de Ae. aegypti. Bioensaios foram realizados para determinar a atividade entomopatogênica do bacilo contra Ae. aegypti e as concentrações letais (CL50 e CL90) foram estimadas após os testes. As técnicas de Reação em Cadeia da Polimerase e SDS-PAGE foram realizadas para verificar o conteúdo de genes e proteínas dos isolados, respectivamente. Os solos dos ecossistemas de mangue e restinga apresentaram potencial para obtenção de B. thuringiensis. O isolado BtMA-750, obtido a partir da amostra de solo da restinga, foi interessantemente distinguido por sua alta toxicidade para Ae. aegypti. Este isolado, além de apresentar proteínas com massa molecular semelhante às toxinas Cry e Cyt, apresentou também diversos genes díptero-específicos cry e cyt, demonstrando que tem alto potencial para ser usado no controle biológico de Ae. aegypti.


Asunto(s)
Humanos , Animales , Bacillus thuringiensis/genética , Aedes , Brasil , Control Biológico de Vectores , Ecosistema , Mosquitos Vectores , Larva
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