Pre-Amazon Region Research Articles

Characterization of Allergies in a Riverside Population in the Pre-Amazon Region

Characterization of Allergies in a Riverside Population in the Pre-Amazon Region

Clinical and Epidemiological Assessment of Children and Adolescents Hospitalized with SARS-CoV-2 in the Pre-Amazon Region.

SARS-CoV-2 infection usually presents similarly to other respiratory viral pathogens. Children and adolescents do not present as a group that is highly affected by the disease, having low infection rates. However, limited publications are associated with the findings of pneumonia in pediatric patients with COVID-19. To analyze the clinical and epidemiological aspects of children and adolescents hospitalized with SARS-CoV-2 in a pre-Amazon region. A retrospective study, carried out in four public hospitals in São Luís, Brazil where medical records of children and adolescents aged from 0 to 13 years, of both sexes, with clinical diagnosis of community-acquired pneumonia were evaluated from March 2020 to March 2021. Almost 40.0% of children were aged between 1 year and 5 years. Of the 128 children who had SARS-CoV-2, 3 are of indigenous ethnicity. Additionally, 78.6% of the children had fever and there was no significant difference between COVID-19 patients and those of other respiratory viruses. Eighteen patients had chronic neurological disease, which is the most common comorbidity observed in patients with coronavirus infection. Ground glass opacity attenuation was observed in 24.8% of children and adolescents with COVID-19. Anemia and increased inflammatory response markers were related to SARS-CoV-2 infection. More than 90.0% of patients admitted to hospital, regardless of etiology, were treated with antibiotics. Eighteen patients died. Pediatric multisystem inflammatory syndrome (PMIS) was diagnosed in 17 patients. SARS-CoV-2 in children and adolescents is mild, but the condition of patients with PMIS is more serious, with an increase in inflammatory biomarkers which can lead to death. Therefore, rapid diagnosis and differentiation of agents causing respiratory diseases are necessary for better therapeutic decision making, since the results of this study make us question the excessive use of antibiotics without meeting well-defined clinical-epidemiological criteria.

Análise multifractal das plantas-daninhas em sistema de semeadura direta na região Pré-Amazônia

ABSTRACT Weeds have several mechanisms of dispersal and reproduction, resulting high spatial variability. The objective of this study was to assess the scale and spatial heterogeneity of weeds using multifractal analysis in a no-tillage system in the Pre-Amazon region. Sampling was conducted in a commercial soybean (Glycine max) production plot in the Mata Roma, Maranhão, Brazil, comprising 1,071 points marked on a 10 × 10 m grid. Data were analyzed using descriptive statistics and multifractal analysis through the box-counting method. Weeds showed varying degrees of multifractality, resulting in different scales and spatial heterogeneity in the study area. Euphorbia hirta and Turnera subulata exhibited asymmetry of branches to the left in the singularity spectrum, indicating dominance of high measurement values.

High Incidence of Respiratory Syncytial Virus in Children with Community-Acquired Pneumonia from a City in the Brazilian Pre-Amazon Region.

Although fewer children have been affected by the severe form of the coronavirus disease 2019 (COVID-19), community-acquired pneumonia (CAP) continues to be the leading global cause of child hospitalizations and deaths. This study investigated the incidence of respiratory syncytial virus (RSV) as well its subtypes (RSV A and B), adenovirus (ADV), rhinovirus (HRV), metapneumovirus (HMPV), coronavirus (NL63, OC43, 229E and HKU1), parainfluenza virus subtypes (PI1, PI2 and PI3), bocavirus and influenza A and B viruses (FluA and FluB) in children diagnosed with CAP during the COVID-19 pandemic. A total of 200 children with clinically confirmed CAP were initially recruited, of whom 107 had negative qPCR results for SARS-CoV-2 and were included in this study. Viral subtypes were identified using a real-time polymerase chain reaction in the nasopharyngeal swab samples. Viruses were identified in 69.2% of the patients. RSV infections were the most frequently identified (65.4%), with type RSV B being the most prevalent (63.5%). In addition, HCoV 229E and HRV were detected in 6.5% and 3.7% of the patients, respectively. RSV type B was associated with severe acute respiratory infection (ARI) and a younger age (less than 24 months). New strategies for preventing and treating viral respiratory infections, particularly RSV infections, are necessary.

Limnological Quality: Seasonality Assessment and Potential for Contamination of the Pindaré River Watershed, Pre-Amazon Region, Brazil

Watersheds are defined as a set of lands where water drainage occurs through rivers and their tributaries. A large quantity of water resources exist in the state of Maranhão, Brazil, where rivers and their basins must meet environmental quality standards defined by the limits set out in national environmental council (CONAMA) legislation 357/05 for physicochemical and microbiological parameters, including parasites. Multivariate statistical techniques were applied to study the temporal and spatial variations in water quality of a segment of the Pindaré River. The data set included nine parameters for three sampling points over eleven months. Principal component analysis grouped the monitored sampling points into four clusters and identified electrical conductivity, temperature, total dissolved solids (TDS), pH, salinity, and Escherichia coli as being associated with the dry season and nitrite, nitrate, and turbidity as being associated with the rainy season. Three principal components explained 83.80% of the data variance during the rainy and dry seasons. The evaluated correlations indicated that during the rainy season, nitrite (~0.18 mg L−1) and turbidity (~46.00 NTU) levels were the highest, but pH was at its lowest (~6.61). During the dry season, TDS (~155.00 mg L−1) and pH (~8.10) were highest, and E. coli bacteria was more abundant.

Dynamics and stability of Marandu grass tillers in monocrop systems and babassu palm silvopastoral systems

This study aimed to evaluate the dynamics, population density of tillers and stability index of Urochloa brizantha in silvopastoral systems composed of babassu palm trees in the Pre-Amazon region. Four systems consisting of different densities of palm trees (80, 131, and 160 palms ha-1) and a monocrop were evaluated. The rates at which the basal tillers appeared in systems with 131 and 160 palms ha-1 were similar to each other and were slower compared to the monocrop pasture and the system with 80 palms ha-1. Despite the variations, the stability index was always higher than 1.0, which infers a compensatory mechanism between tiller appearance and mortality rate, since monocrop pastures and systems with 80 palms ha-1 have a higher rate of tissue turnover with high rates of tiller appearance and mortality; in contrast, the system with 160 palms ha-1 presents high tiller survival rates. Both the 160 and 131 palms ha-1 systems indicate impaired canopy renewal, as seen in the low appearance rate of basal tillers due to shading. As such, the tillering dynamics of the systems vary according to the density of palm trees, and the smaller tree densities favor the tiller turnover in the first generations evaluated.

Sugarcane Varieties for Animal Feeding in the Pre-Amazon Region of Brazil

The expansion of agricultural frontiers in Brazil has resulted in the growth of ruminant production in the Pre-Amazon Region. However, this production is favored mainly in the rainy season, due to the greater supply of pasture for the animals. This fact limits the maintenance of production due to the lack of quality forage for the animals throughout the year. This work aimed to evaluate the nutritional value of the different sugarcane varieties for animal feeding during four crop cycles. In this experiment, the varieties RB 92579, RB 867515 and RB 863129 were studied for cane plant, first, second and third ratoons. The experiment was divided in four stages according to each cycle, and each cycle lasted approximately 10 to 11 months. For the productivity analysis and other parameters samples were collected at the end of each experimental cycle, when the dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), Brix, NDF/Brix and produtctivity were determined. The RB 92579 variety showed higher productivity (P < 0.05) in all the studied cycles, and remained above the national productivity average in all the cycles (±75 ton ha-1). This same variety, presented the best results for all nutricional parameters (DM, CP, NDF, ADF and FDN/Brix) when compared to the other varieties. The productivity/nutritional relation value must be taken into account when choosing a variety for animal feeding, being the RB 92579 variety the most expressive, during four cycles, wich lasted 4 years.

Occurrence and partitioning of antifouling booster biocides in sediments and porewaters from Brazilian Northeast

Fouling organisms attach and grow on submerged surfaces causing several economic losses. Thus, biocides have been introduced in antifouling paints in order to avoid this phenomenon, but their widespread use became a global problem, mainly in ports, leisure and fishing boat harbors, since these substances can be highly toxic to non-target organisms. The occurrence and environmental behavior of antifouling biocides are especially unknown in some peculiar regions, such as Amazon areas. Thus, the aim of this work was to evaluate, for the first time, levels and the partitioning behavior of the antifouling organic biocides irgarol, diuron and also stable degradation products of dichlofluanid and diuron (DMSA and DCPMU, respectively) in sediments and porewaters from a high boat traffic area located in the Northeast of Brazil, a pre-Amazon region. Our results showed high concentrations of irgarol (<1.0–89.7 μg kg−1) and diuron (<5.0–55.2 μg kg−1) in sediments. In porewater, DCPMU (<0.03–0.67 μg L−1) and DMSA (<0.008–0.263 μg L−1) were the mainly substances detected. High Kd and Koc obtained for both irgarol and diuron showed a partitioning preference in the solid phase. This work represents one of the few registers of contamination by antifouling substances in Amazonian areas, despite their environmental relevance.

Sunflower Genotype Selection for Oil Production in the Pre-Amazon Region of Brazil

Part of the energy consumed in the world comes from limited sources, which eventually are expected to be depleted. The search for alternative sources to meet energy needs is crucial. Biodiesel derived from vegetable oils and animal fats stands out as a biodegradable and renewable alternative source of energy. Sunflower is among the top four oil crops produced worldwide, and Brazil has a high production potential for this crop. This study aimed to identify the sunflower genotypes with the highest potential for biodiesel production in the Pre-amazon region of Brazil, where the advance of agricultural frontier represents an important role on biodiesel production. This study was conducted over 2 years of observations. The following genotypes were used: M734 (T), Helio358, EMBRAPA 122, and BRS G 35. The following parameters were assessed: initial flowering date (IFD), physiological maturity date (PMD), plant height (PH), grain yield (YIELD), thousand achene weight (TAW), and oil content (%OC). The climatic conditions of each experimental period were distinctive and directly affected the results obtained. The genotype Embrapa 122 showed the best performance regarding yield and was recommended for the pre-Amazon region of Brazil as the best adapted genotype to the local environmental conditions.

Factors associated with leprosy in a municipality of the Pre-Amazon region, state of Maranhão, Brazil.

The Integrated Program of Leprosy Control was initiated in the municipality of Buriticupu, Maranhão, Brazil, an area considered hyperendemic for leprosy in 2003. It aims at assessing the clinical and epidemiological characteristics of the disease to reduce the detection rate of new cases until 2015. Here, we present the evolution of the indicators of leprosy within the period from 2003 to 2015. We conducted a descriptive analytical study based on the active search for and voluntary referral of cases of leprosy. The detection rate of new cases was analyzed over time. We included individuals diagnosed with leprosy between January 2003 and December 2015. The association between categorical variables was assessed using the chi-square test of independence, considering a level of significance of 5%. When the association was significant, the detection rate (with a confidence interval of 95%) was calculated. Overall, 879 new leprosy cases were detected; the majority of the affected individuals were men (65.9%). Multibacillary leprosy was the most common type of the disease, according to the operational classification (55.5%); it showed the strongest association with an age ≥60 years. We also detected an association between the male sex and both, lepromatous and multibacillary leprosy. The detection rate reduced from 211.09/100,000 population in 2003 to 50.26/100,000 population in 2015. We found an improvement in leprosy control, with a reduction in the detection rate and the absolute number of cases. Strengthening of disease control measures should be prioritized to eliminate leprosy as a public health concern in this municipality.

Nutrient intake and economic analysis of young bulls reared in silvopastoral systems with babassu palm trees in the Pre-Amazon region

SUMMARY This study evaluated the intake of dry matter (IDM), nutrients and the economic analysis of F1 young bulls from the cross between Nellore and Guzera on pastures of Urochloa brizantha cv. Marandu in silvopastoral systems composed of babassu palm (Attalea speciosa) and Marandu monoculture in the Pre-Amazon region of the state of Maranhão. Animals were evaluated in four systems consisting of 0, 80, 131, 160 palms ha-1, characterizing monoculture (MC), low density of palm trees (LDP), average density of palm trees (ADP) and high density of palm trees (HDP) during the rainy (RP) and dry (DP) periods. The dry matter intake, in g day-1, %BW and g kg-075 was influenced by the densities of babassu palm trees (P&lt;0.05). In both evaluation periods, the animals kept on monoculture consumed more forage. Animals kept on HDP consumed greater amounts of CP in both periods, approximately 478.20 and 599.18 g day-1 for DP and RP, respectively. The intake of NDF was affected by periods and palm densities (P&lt;0.05). There was a higher intake of NDF for animals kept on MC, in both periods. Of the four systems evaluated, only LDP resulted in a revenue per hectare higher than the costs, making it the only profitable system. However, in a five-year simulation, all systems resulted in an internal rate of return higher than 6,87% the rate of attractiveness, and the LDP system had the best result. All analyzed systems had a benefit/cost ratio greater than one; i.e., all are economically viable.

&lt;b&gt;Symbiosis of rhizobia with &lt;i&gt;Gliricidia sepium &lt;/i&gt; and &lt;i&gt;Clitoria fairchildiana&lt;/i&gt; in an Oxisol in the pre-Amazon region of Maranhão State

Gliricidia ( Gliricidia sepium ) and sombreiro ( Clitoria fairchildiana ) have been recommended for agroforestry systems and reforestation of degraded areas due to their fast growth and symbiosis with rhizobia. However, little is known about native populations that nodulate these species. The objective of this study was to evaluate the phenotypic and genetic diversity of nitrogen-fixing bacteria isolated from nodules of gliricidia and sombreiro in alley cropping systems located in the pre-Amazon region of Maranhao State and to confirm their nodulation ability. Nodules were field collected from 20 plants of each species. The isolated strains were characterized morphologically, their 16S rRNA gene was partially sequenced, and their symbiotic ability was authenticated in siratro ( Macroptilium atropurpureum ). Despite being in the same climate and soil conditions, gliricidia and sombreiro are nodulated by different rhizobia genera, with Rhizobium predominant in gliricidia and Bradyrhizobium in sombreiro. Endophytic strains also colonized nodules in the field. Approximately 60% of Rhizobium strains did not nodulate siratro, whereas all Bradyrhizobium strains did. Native strains isolated from gliricidia nodules had low efficiency, and only four strains isolated from sombreiro nodules were efficient in siratro. These results highlight the importance of symbiotic relationships in the regulation of biological nitrogen fixation.

Nutritional value of sugarcane varieties in relation to nitrogen fertilization for the pre-Amazon Region of Brazil

This study evaluated the nutritional value of sugarcane varieties in relation to nitrogen fertilization. The varieties studied were RB 863129, RB 867515, and RB 92579, and nitrogen fertilizer was applied at doses of 0, 60, 80, 120, and 140 kg N ha-1. The experiment was divided into two stages: i) Year I - plant cane, when the yield and nutritional quality of the three sugarcane varieties were evaluated; ii) Years II and III, when and the effect of nitrogen fertilization on the nutritional quality of the first and second ratoon crops of the same varieties was evaluated. In plant cane the yield (t ha-1) and DM (dry matter) and CP (crude protein) contents were higher for the RB 863129 variety. There was no difference between the varieties regarding their NDF (neutral detergent fiber) and ADF (acid detergent fiber) contents and IVDMD (in vitro dry matter digestibility). In the first and second ratoon crops, there was a difference between the varieties and fertilizer doses for the evaluated parameters, with the exception of the DM content and IVDMD, which were influenced by the varieties, doses of N, and cutting years. The RB 92579 variety showed the best yield of the two ratoon crops (131 t ha-1 of stems) and the best nutritional parameters (26% ADF, 41% NDF, 2.4% CP, and 69.4% IVDMD). The sugarcane yield and its nutritional quality can be influenced by the cutting year and nitrogen fertilization management system and by the variety type.

&lt;b&gt;Grazing behavior and spatial distribution of feces of Young bulls in silvopastoral systems and Marandu monoculture in the Pre-Amazon region

The objective was to evaluate the grazing behavior and the spatial distribution of feces of F1 young bulls from the cross between Nellore and Guzera on pastures of Urochloa brizantha cv. Marandu in silvopastoral systems composed of babassu palm (Attalea speciosa) and Marandu monoculture in the Pre-Amazon region of the state of Maranhão. Animals were evaluated in four systems consisting of 0, 80, 131, 160 palms ha-1, characterizing monoculture (mono), low density of palm trees (LD), medium density of palm trees (MD) and high density of palm trees (HD) during the rainy (RE) and dry (DE) periods. Five animals (repetitions) were used in each system, with 231-303 days of age and 180±15 kg body weight. Determinations of behavioral patterns were made by instant sampling, at 10 min intervals. In each system, we demarcated 50 squares of 100 m2, which served as useful area to evaluate the dispersion of feces. The grazing behavior was influenced by the sward structure, which, in turn, was influenced by densities of palm trees, due to shading. The distribution of feces was affected by both the presence of babassu plantations and periods. The silvopastoral systems made the environment more pleasant to animals, since activities considered more stressful and avoided during the daytime were performed by animals of these environments, unlike animals in the monoculture system.

English

The great expansion of sugar cane production to non-traditional regions in Brazil has demonstrated the importance of knowledge on the growth characteristics to maintain the productivity and sustainability of the sector. Among the alternatives available to evaluate different varieties of sugar cane, the growth analysis has been one of the most used tools. The objective of this study was to evaluate the growth and development of three varieties of sugar cane for the Pre-Amazon region of Brazil. The varieties used were RB 867515, RB 863129 and RB 92579, and the following parameters of growth were evaluated: accumulation of biomass on the part area, leaf area, number of plants, height of stems, the nitrogen content in different parts of the plant (stem and leaf+3), brix and productivity. For that, samples were collected at 60, 120, 180, 240 and 300 days after planting. For all collecting dates and at 300 days after planting the variety RB 863129 presented better results (P 0.05) for the varieties RB 863129 and RB 92579. Leaf area was greater (P<0.05) for the variety RB 867515; and nitrogen content of stems were greater for the variety RB 92579 at 300 days after planting. Overall, the RB 863129 variety was the most promising for cultivation in this region during the sugarcane-plant season. Key words: Biomass, crop development analysis, selection of varieties.

Swine manure application methods effects on ammonia volatilization, forage quality, and yield in the Pre-Amazon Region of Brazil

The use of swine manure (SM) as a nutrient source for pastures is increasingly common in Brazil, due to its low cost. However, this practice can cause N losses in agricultural soil, where ammonia (NH3) volatilization may be the main drawback, generating undesirable economic and environmental consequences. The objective of this study was to evaluate SM application methods that retain N within the system and determine how these methods affect forage yield and quality. The study was conducted in the municipality of Chapadinha, Maranhao, Brazil, and the following SM application methods were evaluated: (1) surface application, (2) incorporation at 5-cm soil depth, (3) incorporation at 10-cm soil depth, and (4) control when SM was not applied. Lower N losses due to NH3 volatilization and higher pasture yield and quality were found when SM was incorporated at 10-cm soil depth (83 kg N-NH3 ha-1 and 6.3 Mg DM ha-1, respectively, compared to 86 kg N-NH3 ha-1 and 1.5 Mg DM ha-1 for the control), whereas higher N-NH3 losses and lower pasture yield were observed when SM was applied to the soil surface (143 kg N-NH3 ha-1 and 2.6 Mg ha-1, respectively). Higher quality forage in terms of chemical composition was also observed when SM was incorporated at greater soil depth. Incorporating SM at 10-cm depth represents an efficient management to mitigate N-NH3 volatilization, and this application method is associated with significantly increased in DM yield and improved chemical composition.

Performance of calves receiving a by-product of the babassu oil palm during the dry season in an integrated pasture-forestry system in the pre-Amazon region of Brazil

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Eficiência agronômica de estirpes de rizóbio em feijão-caupi cultivado na região da Pré-Amazônia Maranhense

O objetivo deste trabalho foi avaliar a eficiência agronômica de estirpes de rizóbio para inoculação emcampo,dacultivarBRS Guaribadefeijão-caupi.Os experimentosforamrealizadosemduasáreasemSanta Luzia do Paruá, MA, na região de Pré-Amazônia, em 2009. Foram testadas as estirpes de Bradyrhizobium BR 3299, BR 3262, e INPA 03-11B, um controle absoluto e um tratamento nitrogenado (80 kg ha-1 de N). As avaliações foram realizadas aos 30 e 50 dias após a emergência (DAE) das plantas. Aos 65 DAE, foi avaliada a produtividade de grãos. Foram avaliados número e massa de matéria seca de nódulos, massa de matéria seca da parte aérea, eficiência relativa e acúmulo de N na parte aérea. As estirpes proporcionaram maior número e massa de matéria seca de nódulos, bem como maior produtividade em comparação ao controle absoluto, sem inoculação e sem ureia, nas duas áreas. Para massa de matéria seca da parte aérea, eficiência relativa e acúmulo de N na parte aérea, a estirpe BR 3299 diferiu significativamente do controle absoluto, aos 30 DAE, em uma das propriedades. O feijão-caupi responde positivamente à inoculação com as estirpes, especialmentea BR 3299.

Efficiency of an agrosystem designed for family farming in the pre-Amazon region

AbstractIn the humid tropics, the continuous use of the same area reduces nutrient availability and increases the incidence of weeds. To circumvent these obstacles, farmers practice itinerant agriculture associated with slashing and burning with negative effects on the local and global environment. In search for a suitable system for humid tropical agriculture, the objective of this study was to investigate the performance of no-till alley cropping in conjunction with the use of annual legume crops grown during the off-season. The experiment was implemented in a one-hectare alley cropping system in which the leguminous tree clitoria (Clitoria fairchildiana R.A. Howard) was used. The experimental design consisted of randomized blocks with four replications of the following treatments: Stylosanthis (Stylosanthis capitata), showey rattlebox (Crotalaria spectabilis), sunn hemp (Crotalaria juncea), jack bean (Canavalia ensiformis) and a control with clitoria alone, without an annual legume. In January 2007 and 2008, maize was planted in each alley. One hundred and twenty days after annual legumes were sown, the total biomass was recorded. Weed incidence was assessed 35 days after maize planting. Analyses of the C, N, P, K, Ca and Mg contents of the legumes were carried out. To assess soil organic matter (SOM), composite soil samples from the surface 0–5 cm were collected from experimental plots. Two adjacent areas were also sampled for comparison: a 10-year-old secondary forest and an area of conventional tillage. The SOM was fractionated using a densitometric and a granulometric method. Conventional systems reduce the silt and free light organic matter fractions more than no till. The use of annual legumes changes the composition of the weed community, replacing the more aggressive types with those less competitive. The use of showy rattlebox (C. spectabilis) may be an effective strategy for reducing weed density in the long-season crop. Furthermore, relative to the use of leguminous trees alone, higher yields of maize can be obtained with the use of showy rattlebox (C. spectabilis) and sunn hemp (C. juncea) without the application of additional N.

Nutrient recycling and physical indicators of an alley cropping system in a sandy loam soil in the pre-Amazon region of Brazil

The sustainable management of soils has proved a key challenge for the smallholder agriculture in southeastern Amazonia, Brazil. We assessed the capacity of an alley cropping system to sustain corn productivity. The experiment included six treatments: Clitoria + Pigeon Pea; Leucaena + Pigeon Pea; Acacia + Pigeon Pea; Clitoria + Leucaena; Leucaena + Acacia and Control treatment (no legumes). We determined chemical and physical indicators of soil quality. Leucaena had the highest macronutrient concentrations (40.17 g N kg−1), except for P. All legumes had high Ca (13.82–17.84 g kg−1) and very low P (0.51–2.83 g kg−1) and Mg (1.73–2.92 g kg−1) concentrations. Acacia had the lowest N, P, K and Mg concentrations. Pre-planting soil analysis indicated that soil quality indicators were below the critical levels needed for a productive agricultural system, especially for phosphorus, sum of bases and base saturation. Physical indicators of quality, such as bulk density (1.40–1.30 Mg m−3), total porosity (0.46–0.50 m m−3) and soil aeration capacity (0.10–0.17 m m−3), were substantially improved as a result of the surface application of residues. There was a cumulative effect of residue application on corn crop productivity. Because of its capacity to recycle nutrients and improve soil quality over the period of 3 years, alley cropping in association with no-tillage, can be an efficient strategy for maintaining productivity in the low-fertility soils of the humid tropics.