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1.
Braz J Biol ; 83: e278007, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38126483

RESUMEN

Low density sugarcane plantation (LDSP) has been implemented by some sugarcane producers in Brazil, aiming to save seeds and operational costs. The study was carried out in the municipality of Areia, Paraíba, Brazil. Five planting densities were used, varying from 5 to 25 m-2 of buds arranged in randomized blocks, with four replications. Data were measured annually over three cultivation cycles (2017 to 2020), during which the field was fertilized with NPK and the harvests were carried out manually without prior burning. The lower planting density presents higher productivity only in the cane plant (101.03 t ha-1) due to the higher plant height (2.37 m) and the higher number of stalks (11 stalks m-2), suggesting that these variables are due to the greater availability of light, water and photosynthate. However, there is a drastic reduction in sugarcane yield for this lower population in the 2nd ratoon by up to 65.62%, which is correlated with number of stalks per meter. We demonstrate the agronomic viability of LDSP in the population of 10 buds m-2 in relation to conventional planting of sugarcane until the 2nd ratoon. Data are important for future studies to present additional considerations for other production factors, such as the effects of mechanized harvesting and the management of nutrients and water, assessing the sustainability of this large-scale planting system.


Asunto(s)
Saccharum , Agricultura , Semillas , Agua , Brasil
3.
Mar Pollut Bull ; 140: 364-373, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30803656

RESUMEN

Estuaries provide significant cultural ecosystem services, including recreation and tourism. Disruptions of estuarine biogeochemical processes resulting from environmental degradation could interrupt the flow of these services, reducing benefits and diminishing the welfare of local communities. This study focused on recreational shellfishing in Buzzards Bay, Massachusetts (41.55°N, 70.80°W). Relationships among measures of recreational shellfishing, estuarine water quality, and local socioeconomic conditions were tested to understand how the benefits of cultural ecosystem services to local communities might be affected by declining water quality. Transferring estimated economic benefits from an analysis of nearby municipalities, the study finds that increases in Chl a during the 24-year period were associated with losses in recreational shellfishing benefits of $0.08-0.67 million per decade. The approach presented here suggests a more broadly applicable framework for assessing the impacts of changes in coastal ecosystem water quality on the welfare of local communities.


Asunto(s)
Bahías/química , Conservación de los Recursos Naturales/métodos , Crustáceos/crecimiento & desarrollo , Recreación , Mariscos , Calidad del Agua , Animales , Ciudades/economía , Conservación de los Recursos Naturales/economía , Ecosistema , Estuarios , Massachusetts , Modelos Económicos , Recreación/economía , Mariscos/economía , Factores Socioeconómicos
4.
J Periodontal Res ; 53(5): 736-742, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29687452

RESUMEN

BACKGROUND AND OBJECTIVE: Human beta-defensins (hBDs) contribute to innate immunity antimicrobial activity. They are also effective in the adaptive immune response and may play a crucial role in the susceptibility to diseases of the oral cavity. This study aimed to evaluate the levels of hBD-1 in the gingival crevicular fluid of individuals with and without chronic periodontitis. MATERIAL AND METHODS: Twenty periodontally healthy individuals (H) and 20 individuals with chronic periodontitis were recruited. Gingival crevicular fluid samples were collected from: healthy sites (Hh) from periodontally healthy individuals; and healthy sites (Ph), sites with gingivitis (Pg), and sites with periodontitis (Pp) from individuals with periodontitis. The levels of hBD-1 (pg/mL) were measured using enzyme-linked immunosorbent assay. Comparisons of hBD-1 between individuals (H and chronic periodontitis) and among sites (Hh, Ph, Pg, Pp) were performed through hierarchical linear modeling. RESULTS: Gingival crevicular fluid levels of hBD-1 were: Hh = 229.52 ± 138.96 (median 199.26), Ph = 53.88 ± 58.17 (median 35.75), Pg = 57.11 ± 40.18 (median 39.90) and Pp = 55.31 ± 37.28 (median 54.19). No influence of site diagnosis (level 1; health/gingivitis/periodontitis) was observed; however, individual diagnosis (level 2; health/periodontitis) influenced the levels of hBD-1 (P < .001). CONCLUSION: Periodontally healthy individuals showed higher gingival crevicular fluid levels of hBD-1 when compared to individuals with chronic periodontitis. This suggests a potential protective role of hBD-1 in the susceptibility to chronic periodontitis.


Asunto(s)
Periodontitis Crónica/inmunología , Líquido del Surco Gingival/inmunología , beta-Defensinas/inmunología , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Estudios Transversales , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad
5.
Acta Trop ; 172: 160-163, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28457830

RESUMEN

It has been reported a higher seroprevalence of HBV and HCV in leprosy patients than in the general population, but the reasons for these findings are not yet clear. On the other hand, there is evidence that these viruses may influence the onset of leprosy reactional episodes, an important cause of neurological sequelae. This study aimed to determine seroprevalence and risk factors for HBV and HCV in leprosy patients and to investigate its association with leprosy reactions. Patients attended from 2015 to 2016 at a Reference Center in Leprosy in Northeastern region of Brazil, were interviewed, had their records reviewed to investigate biological, clinical, behavioral and socioeconomic factors, and underwent blood sample collection. Biological samples were tested for HBV (HBsAg, anti-HBs and anti-HBs) and HCV (anti-HCV) serological markers by ELISA and, in anti-HCV positive samples, HCV RNA was screened by real time PCR. SPSS program was used to analyze the data. A total of 403 leprosy patients were included. Although anti-HBc was positive in 14.1%, there was no detection of HBsAg, which contradicts the hypothesis that leprosy patients have immune deficit that make them more prone to chronic HBV infection. Multibacillary leprosy (0.057), health-related work (0.011) and lower educational level (0.035) were associated with anti-HBc positivity. Anti-HCV was positive in 0.5%, with no detection of HCV RNA. No association was identified between anti-HCV and the epidemiological analyzed factors. There was also no association of anti-HBc or anti-HCV with type 1 or type 2 leprosy reactions. Thus, the seroprevalence of HBV and HCV in leprosy patients was similar to that of the general population of Northeastern region of Brazil, and no association of HBV or HCV with leprosy reactions was observed.


Asunto(s)
Hepatitis B/complicaciones , Hepatitis B/virología , Hepatitis C/complicaciones , Hepatitis C/virología , Lepra/complicaciones , Adulto , Anciano , Biomarcadores/sangre , Brasil/epidemiología , Ensayo de Inmunoadsorción Enzimática , Femenino , Hepacivirus/aislamiento & purificación , Anticuerpos contra la Hepatitis B , Antígenos de Superficie de la Hepatitis B , Virus de la Hepatitis B/aislamiento & purificación , Anticuerpos contra la Hepatitis C , Humanos , Lepra/virología , Masculino , Persona de Mediana Edad , Prevalencia , Reacción en Cadena en Tiempo Real de la Polimerasa , Factores de Riesgo , Estudios Seroepidemiológicos , Pruebas Serológicas
6.
Trop Biomed ; 33(2): 246-259, 2016 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33579091

RESUMEN

Here, we evaluated two Toxoplasma gondii SAG2 antigen sequences which differ in the presence of the amino-and carboxy-terminal sequences in one of them. They were tested with several techniques to differentiate between acute and chronic phase of toxoplasmosis: avidity assay and indirect ELISA for the detection of anti-Toxoplasma IgG, IgA and IgM antibodies. Significant differences were found between them. The best results were obtained with the sequence denominated SAG2c, which yielded sensitivity of 73.8% and specificity of 80.3% in the detection of IgG by ELISA. Measurement of IgA yielded 67.2% and 81.8% of sensitivity and specificity, respectively. The avidity assay yielded 100% sensitivity and 81.82% specificity. Finally, the molecular modeling and epitope predictions of the protein are developed to find the antigenic region locations, specific and nonspecific, on three-dimensional structure. This paper is the first report of promising results of SAG2 used for detecting IgA antibodies to differentiate toxoplasmosis infection stages.

7.
Acta Trop ; 150: 111-5, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26200786

RESUMEN

Dermatophytosis in individuals with human immunodeficiency virus infection seems to manifest with atypical, multiple, or extensive lesions more frequently. In addition, there are reports of presentations with little inflammation, called anergics. Less common etiologic agents have been isolated in these individuals, such as Microsporum species. To describe clinical aspects and etiologic agents of dermatophytosis in individuals with human immunodeficiency virus (HIV) infection. Patients with clinical diagnosis of dermatophytosis underwent scarification for mycological diagnosis through direct microscopic examination and fungal isolation in culture on Sabouraud dextrose agar. Sixty individuals had a clinical hypothesis of dermatophytosis. In 20 (33.3%) of the 60 patients, dermatophytosis was confirmed through a mycological study. Tinea corporis, diagnosed in 14 patients, was the most frequent clinical form, followed by tinea unguium in 7, tinea cruris in 5, and tinea pedis in 1 patient. Most of the lesions of tinea corporis were anergic. Five patients with tinea unguium had involvement of multiple nails, with onychodystrophy as the predominant subtype. Multiple cutaneous lesions occurred in 3 patients and extensive cutaneous lesions in 4. Regarding the agent, Trichophyton rubrum was the most commonly isolated. The high occurrence of anergic skin lesions and involvement of multiple nails, especially as onychodystrophy, corroborates the hypothesis that atypical, disseminated, and more severe presentations are common in individuals with HIV infection. However, no Microsporum species was isolated even in atypical, extensive, or disseminated cases, in disagreement with previous reports. Therefore, the approach of squamous lesions in HIV-positive patients must include a mycological study, in view of the possibility of anergic dermatophytosis, to promote the introduction of a suitable therapeutic agent.


Asunto(s)
Infecciones por VIH , Tiña/epidemiología , Trichophyton/aislamiento & purificación , Adulto , Brasil/epidemiología , Femenino , Humanos , Masculino , Tiña/etiología
8.
Oral Dis ; 19(6): 568-76, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23163888

RESUMEN

OBJECTIVE: Susceptibility to and severity of periodontal disease is influenced by gene polymorphisms related to the immune response. Co-stimulatory molecules, such as CD28 and CTLA-4, are critical in the development of such responses. Our hypothesis is that polymorphisms in genes that code for these molecules may be associated with periodontitis. The aim of the study was to investigate the association between +17 (T/C) CD28 and +49 (A/G) CTLA-4 gene polymorphisms and periodontitis in Brazilians. MATERIALS AND METHODS: Genomic DNA was obtained from oral swabs of 424 individuals categorized into three groups (control group, aggressive, and chronic periodontitis) considering clinical parameters such as probing depth and clinical attachment loss. The genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism. RESULTS: There was an association between the T(-) genotype of the CD28 polymorphism and aggressive periodontitis (P = 0.04). Moreover, the A(+) genotype for CTLA-4 was associated with greater clinical attachment loss in non-smokers with aggressive periodontitis (P = 0.006, OR = 16.25, CI = 2.25-117.11). CONCLUSIONS: These findings show that T(-) in CD28 + 17 (T/C) and the A(+) in CTLA-4 +49 (A/G) genotypes are associated with susceptibility to aggressive periodontal disease. Thus, our study highlights these polymorphisms as potential genetic susceptibility markers of periodontitis in Brazilians.


Asunto(s)
Periodontitis Agresiva/genética , Antígenos CD28/genética , Antígeno CTLA-4/genética , Polimorfismo Genético/genética , Adenina , Adolescente , Adulto , Anciano , Periodontitis Agresiva/inmunología , Brasil , Periodontitis Crónica/genética , Periodontitis Crónica/inmunología , Citosina , ADN/análisis , Femenino , Frecuencia de los Genes/genética , Marcadores Genéticos/genética , Predisposición Genética a la Enfermedad/genética , Genotipo , Guanina , Humanos , Masculino , Persona de Mediana Edad , Pérdida de la Inserción Periodontal/genética , Pérdida de la Inserción Periodontal/inmunología , Bolsa Periodontal/genética , Bolsa Periodontal/inmunología , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción/genética , Fumar , Timina , Adulto Joven
9.
Open Dent J ; 3: 184-90, 2009 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-19771178

RESUMEN

IL-10 and TNF-α are cytokines that have complex and opposing roles in the inflammatory responses. G/A polymorphisms at position -1082 of IL10 and -308 of TNFA genes have been reported to influence the expression of IL-10 and TNF-α, respectively. The aim of this study was to investigate the association between the IL10 (-1082) and TNFA (- 308) gene polymorphisms with different clinical forms or severity of periodontitis in a sample of Brazilian individuals. DNA was obtained from oral swabs of 165 Brazilian individuals, which were divided into three groups: individuals with chronic periodontitis, aggressive periodontitis and individuals without clinical evidence of periodontitis. Evaluation of IL10 and TNFA polymorphisms was performed by RFLP analysis. Statistical analysis of data was performed using the Χ² likelihood ratio and Fisher;s exact test. No significant differences in the genotype and allele distribution of either IL10 or TNFA were observed among individuals with different clinical forms or with different degrees of severity of periodontitis. Moreover, combined analysis of IL10 and TNFA polymorphisms did not show any association with periodontal status. As conclusion, the IL10 and TNFA gene promoter polymorphisms investigated are not associated with different clinical forms of periodontitis or with severity of the disease in the Brazilian population polymorphisms.

10.
Proc Natl Acad Sci U S A ; 104(47): 18555-60, 2007 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-18003934

RESUMEN

Biodiversity loss from deforestation may be partly offset by the expansion of secondary forests and plantation forestry in the tropics. However, our current knowledge of the value of these habitats for biodiversity conservation is limited to very few taxa, and many studies are severely confounded by methodological shortcomings. We examined the conservation value of tropical primary, secondary, and plantation forests for 15 taxonomic groups using a robust and replicated sample design that minimized edge effects. Different taxa varied markedly in their response to patterns of land use in terms of species richness and the percentage of species restricted to primary forest (varying from 5% to 57%), yet almost all between-forest comparisons showed marked differences in community structure and composition. Cross-taxon congruence in response patterns was very weak when evaluated using abundance or species richness data, but much stronger when using metrics based upon community similarity. Our results show that, whereas the biodiversity indicator group concept may hold some validity for several taxa that are frequently sampled (such as birds and fruit-feeding butterflies), it fails for those exhibiting highly idiosyncratic responses to tropical land-use change (including highly vagile species groups such as bats and orchid bees), highlighting the problems associated with quantifying the biodiversity value of anthropogenic habitats. Finally, although we show that areas of native regeneration and exotic tree plantations can provide complementary conservation services, we also provide clear empirical evidence demonstrating the irreplaceable value of primary forests.


Asunto(s)
Biodiversidad , Agricultura Forestal , Clima Tropical
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