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1.
Transplant Cell Ther ; 30(10): 1003.e1-1003.e9, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39097096

RESUMEN

High-dose therapy followed by autologous hematopoietic cell transplant (AHCT) remains a viable consolidation strategy for a subset of patients with relapsed or refractory (R/R) lymphomas. BEAM (carmustine, etoposide, cytarabine, and melphalan) is widely recognized as the predominant conditioning regimen due to its satisfactory efficacy and tolerability. Nevertheless, shortages of carmustine and melphalan have compelled clinicians to explore alternative conditioning regimens. The aim of this study was to compare the toxicity and transplant outcomes following BEAM, CBV (carmustine, etoposide, cyclophosphamide), BuMel (busulfan, melphalan), and BendaEAM (bendamustine, etoposide, cytarabine, melphalan). We retrospectively analyzed data from 213 patients (CBV 65, BuMel 42, BEAM 68, BendaEAM 38) with R/R lymphomas undergoing AHCT between 2014 and 2020. Multivariate models were employed to evaluate toxicity and transplant outcomes based on conditioning type. Among grade III to IV toxicities, oral mucositis was more frequently observed with BuMel (45%) and BendaEAM (24%) compared to BEAM (15%) and CVB (6%, P ≤ .001). Diarrhea was more common with BendaEAM (42%) and less frequent with BuMel (7%, P = .01). Acute kidney injury was only found after BendaEAM (11%). Febrile neutropenia and infectious complications were more frequent following BendaEAM. Frequencies of other treatment-related toxicities did not significantly differ according to conditioning type. BendaEAM (odds ratio [OR] 3.07, P = .014) and BuMel (OR 4.27, P = .002) were independently associated with higher grade III to IV toxicity up to D+100. However, there were no significant differences in relapse/progression, nonrelapse mortality, progression-free survival, or overall survival among the four regimens. BuMel and BendaEAM were associated with a higher rate of grade III to IV toxicity. Carmustine-based regimens appeared to be less toxic and safer; however, there were no significant differences in transplant outcomes. The utilization of alternative preparative regimens due to drug shortages may potentially lead to increased toxicity after AHCT for lymphoma.


Asunto(s)
Carmustina , Citarabina , Trasplante de Células Madre Hematopoyéticas , Linfoma , Melfalán , Acondicionamiento Pretrasplante , Trasplante Autólogo , Humanos , Acondicionamiento Pretrasplante/métodos , Masculino , Femenino , Persona de Mediana Edad , Linfoma/tratamiento farmacológico , Linfoma/terapia , Adulto , Carmustina/uso terapéutico , Estudios Retrospectivos , Citarabina/uso terapéutico , Melfalán/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Anciano , Etopósido/uso terapéutico , Busulfano/uso terapéutico , Resultado del Tratamiento , Ciclofosfamida/uso terapéutico
2.
Front Nutr ; 11: 1168715, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38633601

RESUMEN

Background: Dietary composition can modify gene expression, favoring the development of chronic diseases via epigenetic mechanisms. Objective: Our study aimed to investigate the relationship between dietary patterns and NR3C1 gene methylation in users of the Brazilian Public Unified Health System (SUS). Methods: We recruited 250 adult volunteers and evaluated their socioeconomic status, psychosocial characteristics, lifestyle, and anthropometrics. Peripheral blood was collected and evaluated for cortisol levels, glycemia, lipid profile, and insulin resistance; methylation of CpGs 40-47 of the 1F region of the NR3C1 gene was also measured. Factors associated with degree of methylation were evaluated using generalized linear models (p < 0.05). Lifestyle variables and health variables were included as confounding factors. Results: The findings of our cross-sectional study indicated an association between NR3C1 DNA methylation and intake of processed foods. We also observed relevant associations of average NR3C1 DNA across the segment analyzed, methylation in component 1 (40-43), and methylation in component 2 (44-47) with a pattern of consumption of industrialized products in relation to BMI, serum cortisol levels, and lipid profile. These results may indicate a relationship between methylation and metabolic changes related to the stress response. Conclusion: These findings suggest an association of methylation and metabolic alterations with stress response. In addition, the present study highlights the significant role of diet quality as a stress-inducing factor that influences NR3C1 methylation. This relationship is further linked to changes in psychosocial factors, lifestyle choices, and cardiometabolic variables, including glucose levels, insulin resistance, and hyperlipidemia.

3.
Front Neurosci ; 17: 1092406, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37008217

RESUMEN

Brain-derived neurotrophic factor (BDNF) gene regulation plays an important role in long-term memory formation, and the DNA methylation (DNAm) level of BDNF promoters has been associated with episodic memory deficits. Our aim was to explore the association between DNAm levels in BDNF promoter IV with verbal learning and memory performance in healthy women. We conducted a cross-sectional study by recruiting 53 individuals. Episodic memory was assessed by using the Rey Auditory Verbal Learning Test (RAVLT). Clinical interviews, RAVLT, and blood sample collection were assessed in all participants. DNAm was measured on DNA from whole peripheral blood using pyrosequencing. According to generalized linear model (GzLM) analyses, cytosine guanine dinucleotide (CpG) site 5 showed significant associations between learning capacity (LC, p < 0.035), that is, every 1% of DNA methylation at CpG site 5 results in a 0.068 reduction in verbal learning performance. To the best of our knowledge, the current study is the first to show that BDNF DNAm plays an important role in episodic memory.

4.
Ann Med Surg (Lond) ; 65: 102303, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-34094525

RESUMEN

INTRODUCTION: Immune cells contribute with mediators in the protein expression profile of the tumor microenvironment. Levels of plasminogen activator inhibitor-1 (PAI-1) are elevated in non-malignant inflammatory conditions; however, the association between PAI-1 expression and inflammation remains uncertain in oral squamous cell carcinoma (OSCC). This study aimed to investigate PAI-1 expression in mononuclear inflammatory cell infiltrate in OSCC and its role as a prognostic marker. METHODS: Samples were collected from patients with OSCC, treated surgically, and followed for 24 months after the procedure. Thirty-nine tumoral tissue were analyzed using immunohistochemistry. Correlation between protein expression, clinicopathological parameters, and the prognosis was investigated. RESULTS: Positive PAI-1 expression in mononuclear inflammatory cell infiltrate was significantly associated with lymph node status (p = 0.009) and with the cytoplasmic expression of vascular endothelial growth factor A (VEGFA) (p = 0.028). Multivariate analysis revealed weak PAI-1 expression as an independent marker for lymph node metastases, with approximately 8-fold increased risk compared to strong expression (OR = 8.60; CI = 1.54-48.08; p = 0.014). CONCLUSION: Our results suggest that the strong PAI-1 expression in intratumoral inflammatory infiltrate is an indicator of a better prognosis for patients diagnosed with oral squamous cell carcinoma.

5.
Stress ; 24(6): 814-821, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-33977868

RESUMEN

The aim of this study was to investigate socioeconomic stressors predictive of depressive symptoms and possible epigenetic changes in the glucocorticoid receptor - NR3C1-1F - an encoding gene involved in depressive symptoms. A total of 321 adult volunteers from southeastern Brazil were recruited to evaluate depressive symptoms, socio-demographic and economic factors, including food and nutritional security (FNS) or insecurity (FNiS) status, and NR3C1-1F region methylation by pyrosequencing. Depressive symptom determinants were investigated using a Poisson regression model with robust variance. Mann-Whitney tests and structural mediation equation models were used to evaluate the relationship between NR3C1 DNA methylation, FNiS, and depressive symptoms. Multivariate Poisson regression with robust variance adjusted for sex and FNiS and NR3C1-1F region methylation predicted risk factors for depressive symptoms. Mediation analysis revealed that NR3C1-1F region methylation mediated the relationship between FNiS exposure and depressive symptoms as an outcome, and depressive volunteers and FNiS individuals exhibited a significant increase in NR3C1 methylation when compared to healthy individuals and FNS volunteers, respectively. Therefore, we suggest that stress caused by FNiS may lead to depressive symptoms and that NR3C1-1F DNA methylation can act as a mediator of both FNiS and depressive symptoms.


Asunto(s)
Depresión , Inseguridad Alimentaria , Estrés Psicológico , Adulto , Metilación de ADN , Depresión/genética , Epigénesis Genética , Humanos , Regiones Promotoras Genéticas , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Estrés Psicológico/genética
6.
Sci Rep ; 11(1): 6768, 2021 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-33762648

RESUMEN

The NR3C1 glucocorticoid receptor (GR) gene is a component of the stress response system, which can be regulated by epigenetic mechanisms. NR3C1 methylation has been associated with trauma and mental issues, including depression, post-traumatic stress, anxiety, and personality disorders. Previous studies have reported that stressful events are involved in NR3C1 gene methylation, suggesting that its regulation under environmental effects is complex. The present study aimed to analyze associations involving stressors such as socioeconomic status, health conditions, and lifestyle in relation to NR3C1 methylation in adults. This study included 386 individual users of the Brazilian Public Unified Health System (SUS), and evaluated socioeconomic and health conditions, body mass index, cortisol levels, and lifestyle. Data were correlated with NR3C1 methylation, determined using DNA pyrosequencing. The results showed that alcohol consumption, overweight, and high cortisol levels were related to NR3C1 demethylation, while depression was related to its methylation. Habits, lifestyle, and health status may influence NR3C1 gene regulation via methylation, revealing the complexity of environmental impacts on NR3C1 methylation.


Asunto(s)
Consumo de Bebidas Alcohólicas/genética , Cortisona/sangre , Metilación de ADN , Depresión/genética , Sobrepeso/genética , Receptores de Glucocorticoides/genética , Adulto , Biomarcadores , Islas de CpG , Estudios Transversales , Depresión/metabolismo , Susceptibilidad a Enfermedades , Femenino , Estudios de Asociación Genética , Humanos , Masculino , Persona de Mediana Edad , Sobrepeso/metabolismo , Receptores de Glucocorticoides/metabolismo , Factores Socioeconómicos , Adulto Joven
7.
J Psychiatr Res ; 121: 24-30, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31731185

RESUMEN

OBJECTIVE: The aim of this study was to verify determinant factors for depression and analyze the relationship between possible changes in HPA axis and depression, in this case NR3C1 DNA methylation and serum cortisol levels. METHODS: 349 adult volunteers were recruited to evaluate depression, socio-demographic, economic and lifestyle factors, serum cortisol levels and NR3C1 DNA methylation by pyrosequencing. Depression determinant factors were investigated using a Poisson regression model with robust variance (p < 0.05). RESULTS: Poisson regression with robust variance adjusted by gender, tobacco use, self-perceived stress, leisure activity, suicidal ideation, low cortisol levels and NR3C1 DNA methylation was performed and predicted risk factors for depression. Furthermore, depressive volunteers showed a significant increase in NR3C1 DNA methylation when compared to healthy volunteers. CONCLUSIONS: This findings provide a basis for understanding the role of HPA axis in depression, especially its regulation by NR3C1 DNA methylation. Furthermore, it emphasizes the stressful lifestyle risk factors (female, tobacco uso, self perceived stress, leisure activities absence and suicidal ideation) that can contribute to future research and the search for public health policies to improve quality of live, mental and general health.


Asunto(s)
Metilación de ADN , Depresión/metabolismo , Epigénesis Genética , Hidrocortisona/sangre , Sistema Hipotálamo-Hipofisario/metabolismo , Estilo de Vida , Receptores de Glucocorticoides/metabolismo , Estrés Psicológico/metabolismo , Ideación Suicida , Adulto , Brasil/epidemiología , Depresión/sangre , Depresión/epidemiología , Femenino , Humanos , Actividades Recreativas , Masculino , Persona de Mediana Edad , Factores de Riesgo , Factores Sexuales , Fumar/epidemiología , Fumar/metabolismo , Estrés Psicológico/epidemiología , Adulto Joven
8.
Glob Chang Biol ; 24(12): 5867-5881, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30256494

RESUMEN

Amazon forests account for ~25% of global land biomass and tropical tree species. In these forests, windthrows (i.e., snapped and uprooted trees) are a major natural disturbance, but the rates and mechanisms of recovery are not known. To provide a predictive framework for understanding the effects of windthrows on forest structure and functional composition (DBH ≥10 cm), we quantified biomass recovery as a function of windthrow severity (i.e., fraction of windthrow tree mortality on Landsat pixels, ranging from 0%-70%) and time since disturbance for terra-firme forests in the Central Amazon. Forest monitoring allowed insights into the processes and mechanisms driving the net biomass change (i.e., increment minus loss) and shifts in functional composition. Windthrown areas recovering for between 4-27 years had biomass stocks as low as 65.2-91.7 Mg/ha or 23%-38% of those in nearby undisturbed forests (~255.6 Mg/ha, all sites). Even low windthrow severities (4%-20% tree mortality) caused decadal changes in biomass stocks and structure. While rates of biomass increment in recovering vegetation were nearly double (6.3 ± 1.4 Mg ha-1  year-1 ) those of undisturbed forests (~3.7 Mg ha-1  year-1 ), biomass loss due to post-windthrow mortality was high (up to -7.5 ± 8.7 Mg ha-1  year-1 , 8.5 years since disturbance) and unpredictable. Consequently, recovery to 90% of "pre-disturbance" biomass takes up to 40 years. Resprouting trees contributed little to biomass recovery. Instead, light-demanding, low-density genera (e.g., Cecropia, Inga, Miconia, Pourouma, Tachigali, and Tapirira) were favored, resulting in substantial post-windthrow species turnover. Shifts in functional composition demonstrate that windthrows affect the resilience of live tree biomass by favoring soft-wooded species with shorter life spans that are more vulnerable to future disturbances. As the time required for forests to recover biomass is likely similar to the recurrence interval of windthrows triggering succession, windthrows have the potential to control landscape biomass/carbon dynamics and functional composition in Amazon forests.


Asunto(s)
Biomasa , Bosques , Árboles , Viento , Brasil , Carbono , Clima Tropical
9.
Acta amaz. ; 48(2): 85-92, Apr-June 2018. tab, ilus, graf
Artículo en Inglés | VETINDEX | ID: vti-734661

RESUMEN

The Amazon forest comprises many different forest types, amongst them are campinas and campinaranas, which occur on Amazonian sandy soils, representing 2.65% of Amazonian territory. An understanding of the ecology and quantification of the environmental goods and services of campinaranas is key to their conservation. Based on a direct method to estimate biomass and carbon content of campinarana, we harvested and weighted 89 trees and other forest components in ten randomly allocated plots of 100 m2 (10 x 10 m) and 11 additional trees outside the plots. The data allowed us to describe how biomass is distributed amongst campinarana vegetation and amongst tree compartments. We developed allometric equations to estimate the total, above- and below-ground biomass and carbon stock of this forest type. We used a Weibull function to test if the diameter distribution of the individual trees sampled was consistent with the diameter distribution of the forest type. We also tested if terra-firme forest biomass equations could be used to estimate campinarana biomass, and whether a correction factor based on dominant height would reduce the error from these estimates. Allometric equations are considered to be the most reliable and rapid method for calculating forest biomass, and are used in forest management and climate change studies. These are the first total biomass equations developed for central Amazonian campinaranas. The best fitted allometric equation for total fresh biomass was: ln (Total Biomass) = -1.373 + 2.546 * ln DBH (R ² = 0.98, Sxy% = 4.19%).(AU)


Entre as diversas fitofisionomias da Floresta Amazônica estão as campinas e campinaranas, que ocorrem sobre solos arenosos, ocupando 2,65% de seu território. Baseando-se no método direto, com a finalidade de estimar carbono e biomassa de uma campinarana na Amazônia Central, derrubamos, medimos e pesamos 89 árvores e outros componentes florestais em dez parcelas de 100 m² (10 x 10m) alocadas aleatoriamente, e mais 11 árvores fora das parcelas. A partir dos dados coletados, desenvolvemos equações alométricas para estimar a biomassa total, aérea e de raízes e o estoque de carbono para esse tipo florestal. A função Weibull foi utilizada para comprovar que a distribuição diamétrica das árvores coletadas é análoga a esse tipo florestal. Verificamos, ainda, qual o erro gerado ao se estimar a biomassa da campinarana utilizando equações desenvolvidas para florestas densas de terra-firme, e se o uso de um fator de correção baseado na altura dominante reduziria esse erro. O uso de equações alométricas é considerado o método mais preciso e rápido na obtenção da biomassa florestal, e é utilizado em questões ligadas, entre outras, às áreas de manejo florestal e de clima. Essas são as primeiras equações de biomassa total desenvolvidas para campinaranas nesta região da Amazônia. A melhor equação ajustada para estimar a biomassa total foi: ln(PFtotal) = -1,373 + 2,546 * ln(DAP) (R²=0,98; Sxy%= 4,19).(AU)


Asunto(s)
Ecosistema Amazónico , Carbono , Biomasa , Bosques , Cambio Climático
10.
J Oral Pathol Med ; 47(6): 566-574, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29693741

RESUMEN

BACKGROUND: In oral squamous cell carcinoma (OSCC), the HIF-1 complex promotes the expression of genes involved in specific mechanisms of cell survival under hypoxic conditions, such as plasminogen activator inhibitor-1 (PAI-1), carbonic anhydrase 9 (CAIX), and vascular endothelial growth factor A (VEGFA). The study aimed to investigate the presence and prognostic value of PAI-1, CAIX, and VEGFA in OSCC. MATERIALS AND METHODS: Immunohistochemistry was used to analyze the expressions of these proteins in 52 tumoral tissue samples of patients with OSCC, surgically treated and followed by a minimum of 24 months after surgery. The correlations between protein expressions and clinicopathological parameters and prognosis were analyzed. RESULTS: Positive PAI-1 membrane expression was significantly associated with local disease relapse (P = .027). Multivariate analysis revealed that the positive PAI-1 membrane expression is an independent marker for local disease relapse, with approximately 14-fold increased risk when compared to negative expression (OR = 14.49; CI = 1.40-150.01, P = .025). Strong PAI-1 cytoplasmic expression was significantly associated with the less differentiation grade (P = .027). Strong CAIX membrane expression was significantly associated with local disease-free survival (P = .038). Positive CAIX cytoplasmic expression was significantly associated with lymph node affected (P = .025) and with disease-specific survival (P = .022). Multivariate analysis revealed that the positive CAIX cytoplasmic expression is an independent risk factor for disease-related death, increasing their risk approximately 3-fold when compared to negative expression (HR = 2.84; CI = 1.02-7.87, P = .045). Positive VEGFA cytoplasmic expression was significantly associated with less differentiation grade (P = .035). CONCLUSION: Our results suggest a potential role for these expressions profiles as tumor prognostic markers in OSCC patients.


Asunto(s)
Antígenos de Neoplasias/biosíntesis , Biomarcadores de Tumor/biosíntesis , Anhidrasa Carbónica IX/biosíntesis , Neoplasias de la Boca/metabolismo , Inhibidor 1 de Activador Plasminogénico/biosíntesis , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Factor A de Crecimiento Endotelial Vascular/biosíntesis , Anciano , Antígenos de Neoplasias/metabolismo , Biomarcadores de Tumor/metabolismo , Anhidrasa Carbónica IX/metabolismo , Supervivencia sin Enfermedad , Femenino , Humanos , Inmunohistoquímica , Ganglios Linfáticos/patología , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/patología , Análisis Multivariante , Recurrencia Local de Neoplasia/metabolismo , Recurrencia Local de Neoplasia/patología , Inhibidor 1 de Activador Plasminogénico/metabolismo , Pronóstico , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Análisis de Supervivencia , Factor A de Crecimiento Endotelial Vascular/metabolismo
11.
PLoS One ; 13(3): e0194884, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29590186

RESUMEN

AIMS: Jumonji Domain-Containing 1A (JMJD1A) protein promotes demethylation of histones, especially at lysin-9 of di-methylated histone H3 (H3K9me2) or mono-methylated (H3K9me1). Increased levels of H3 histone methylation at lysin-9 (H3K9) is related to tumor suppressor gene silencing. JMJD1A gene target Adrenomeduline (ADM) has shown to promote cell growth and tumorigenesis. JMJD1A and ADM expression, as well as H3K9 methylation level have been related with development risk and prognosis of several tumor types. METHODS AND RESULTS: We aimed to evaluate JMJD1A, ADM, H3K9me1 and H3K9me2expression in paraffin-embedded tissue microarrays from 84 oral and oropharyngeal squamous cell carcinoma samples through immunohistochemistry analysis. Our results showed that nuclear JMJD1A expression was related to lymph node metastasis risk. In addition, JMJD1A cytoplasmic expression was an independent risk marker for advanced tumor stages. H3K9me1 cytoplasmic expression was associated with reduced disease-specific death risk. Furthermore, high H3K9me2 nuclear expression was associated with worse specific-disease and disease-free survival. Finally, high ADM cytoplasmic expression was an independent marker of lymph node metastasis risk. CONCLUSION: JMJD1A, H3K9me1/2 and ADM expression may be predictor markers of progression and prognosis in oral and oropharynx cancer patients, as well as putative therapeutic targets.


Asunto(s)
Adrenomedulina/metabolismo , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/secundario , Histonas/metabolismo , Histona Demetilasas con Dominio de Jumonji/metabolismo , Neoplasias de la Boca/patología , Neoplasias Orofaríngeas/patología , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/cirugía , Epigénesis Genética , Femenino , Estudios de Seguimiento , Regulación Neoplásica de la Expresión Génica , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/metabolismo , Neoplasias de la Boca/cirugía , Recurrencia Local de Neoplasia/metabolismo , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/cirugía , Neoplasias Orofaríngeas/metabolismo , Neoplasias Orofaríngeas/cirugía , Pronóstico , Tasa de Supervivencia
12.
PLoS One ; 9(8): e103711, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25099118

RESUMEN

Canopy gaps created by wind-throw events, or blowdowns, create a complex mosaic of forest patches varying in disturbance intensity and recovery in the Central Amazon. Using field and remote sensing data, we investigated the short-term (four-year) effects of large (>2000 m(2)) blowdown gaps created during a single storm event in January 2005 near Manaus, Brazil, to study (i) how forest structure and composition vary with disturbance gradients and (ii) whether tree diversity is promoted by niche differentiation related to wind-throw events at the landscape scale. In the forest area affected by the blowdown, tree mortality ranged from 0 to 70%, and was highest on plateaus and slopes. Less impacted areas in the region affected by the blowdown had overlapping characteristics with a nearby unaffected forest in tree density (583 ± 46 trees ha(-1)) (mean ± 99% Confidence Interval) and basal area (26.7 ± 2.4 m(2) ha(-1)). Highly impacted areas had tree density and basal area as low as 120 trees ha(-1) and 14.9 m(2) ha(-1), respectively. In general, these structural measures correlated negatively with an index of tree mortality intensity derived from satellite imagery. Four years after the blowdown event, differences in size-distribution, fraction of resprouters, floristic composition and species diversity still correlated with disturbance measures such as tree mortality and gap size. Our results suggest that the gradients of wind disturbance intensity encompassed in large blowdown gaps (>2000 m(2)) promote tree diversity. Specialists for particular disturbance intensities existed along the entire gradient. The existence of species or genera taking an intermediate position between undisturbed and gap specialists led to a peak of rarefied richness and diversity at intermediate disturbance levels. A diverse set of species differing widely in requirements and recruitment strategies forms the initial post-disturbance cohort, thus lending a high resilience towards wind disturbances at the community level.


Asunto(s)
Biodiversidad , Bosques , Nave Espacial , Árboles/fisiología , Viento , Brasil
13.
Acta amaz. ; 42(4)2012.
Artículo en Portugués | VETINDEX | ID: vti-450756

RESUMEN

This study analyzed data from three forest inventories conducted in the Experimental Forest, which belongs to Embrapa Western Amazon basin and is located at km 54 on BR-174, Manaus / AM. The aim was to study forest dynamics - the rates of recruitment, growth and mortality - in addition to carbon storage in an area of primary forest, without any intervention. The surveys were conducted in the years 2005, 2007 and 2010 in 15 permanent plots of 1 hectare each. There, all trees with diameter at breast height (DBH) above 10 cm were measured. We calculated the rates of recruitment and mortality, the periodic annual increments (PAIs) in terms of DBH, basal area and volume, fresh and dry biomass above the soil and total carbon storage in the vegetation. The recruitment rates were 2.0 percent and 1.8 percent, and mortality were 0.95 percent and 1.3 percent for the periods between 2005 and 2007 and 2007 and 2010, respectively. The volume was 345.62 m3 ha-1 for the year 2005, rising to 360.67 m3 ha-1 in 2010 with PAIs of 4.32 m3 ha-1 yr-1 between 2005 and 2007 and 1.31 m3 ha-1 yr-1 between 2007 and 2010. The total carbon storage increased from 173.63 t C ha-1 in 2005 to 181.01 t C ha-1 in 2010, confirming that the forest accumulated carbon in the period, acting as a sink.


Este trabalho analisou dados de três inventários florestais realizados na área da Floresta Experimental, pertencente à Embrapa Amazônia Ocidental e localizada no km 54 da BR-174, em Manaus/AM. O objetivo foi estudar a dinâmica da floresta - taxas de incremento, recrutamento e mortalidade - além do estoque de carbono, em uma área de floresta primária, sem qualquer tipo de intervenção. Os inventários foram realizados nos anos de 2005, 2007 e 2010, em 15 parcelas permanentes de 1 hectare cada, onde foram mensuradas todas as árvores com diâmetro a 1,3 m de altura do solo (DAP) superior a 10 cm. Foram calculadas as taxas de recrutamento e mortalidade, os incrementos periódicos anuais (IPAs) em termos de DAP, área basal e volume, as biomassas fresca e seca acima do nível do solo e total e o estoque de carbono da vegetação. As taxas de recrutamento foram de 2% e 1,8% e as de mortalidade foram de 0,95% e 1,3% para os períodos entre 2005 e 2007 e 2007 e 2010, respectivamente. O volume foi de 345,62 m3 ha-1 para o ano de 2005, aumentando para 360,67 m3 ha-1 em 2010, com IPAs de 4,32 m3 ha-1 ano-1 entre 2005 e 2007 e 1,31 m3 ha-1 ano-1 entre 2007 e 2010. O estoque de carbono total teve um acréscimo de 173,63 t C ha-1 em 2005 para 181,01 t C ha-1 em 2010, confirmando que a floresta acumulou carbono no período, atuando assim como sumidouro.

14.
Acta amaz. ; 41(3)2011.
Artículo en Portugués | VETINDEX | ID: vti-450681

RESUMEN

In an ethnobotanical survey conducted within "Quilombola" communities of Oriximiná, Pará State, "saracuramirá" (SAR), Ampelozizyphus amazonicus Ducke, stood out as one of the most cited species with wide popular use, especially for malaria, as tonic and depurative. The aim of this paper was to carry out an ethnopharmacognostic study of SAR in these communities. Quantitative ethnobotanical analysis of the data showed that SAR stands out as one of the 10 most versatile species with a high relative importance (1,3); it remains among the five species with the greatest cultural importance, demonstrated by the high salience index (0,311), being the species with the highest major use agreement to malaria (85,7%). Analysis of the foam and hemolysis indexes of SAR shows the presence of saponins with high foam index (833) and low hemolytic activity (HD50 2,6 mg mL-1). In order to analyze SAR saponin aglycones, the drink was prepared by the traditional quilombola method (BMT), was hydrolyzed, and analyzed by gas chromatography after reaction with diazomethane. Two major peaks were characterized by mass spectrometry, one referring to a dammarane triterpene skeleton, characteristic from the SAR saponins, and the other identified as the methyl ester of betulinic acid. Owing to the popular usage of SAR, its in vitro acetylcholinesterase inhibitory activity was evaluated, but with negative results. However, it is possible to suggest that the indications of this plant as a tonic and for treating malaria may be related to an adaptogen and immunostimulant effect due to the presence of saponins and betulinic acid in BMT.


Um levantamento etnobotânico realizado em comunidades quilombolas de Oriximiná, Pará, destacou a saracuramirá (SAR), Ampelozizyphus amazonicus Ducke, com vasto uso popular no tratamento da malária, como tônica e depurativa. Por este motivo, o presente trabalho objetivou realizar um estudo etnofarmacognóstico da SAR nas respectivas comunidades. Por meio de uma análise etnobotânica quantitativa, foi verificado que SAR apresentou-se dentre as 10 espécies mais versáteis pela elevada importância relativa (1,3), dentre as cinco espécies com maior importância cultural pelo elevado índice de saliência (0,311) e a espécie com maior concordância de uso principal para malária (85,7%). Uma análise do índice de espuma e do índice de hemólise para SAR demonstra a presença de saponinas com elevado índice de espuma (833) e uma baixa atividade hemolítica (CH50 2,6 mg mL-1). Para realizar uma análise das agliconas das saponinas de SAR, a bebida preparada pelo método tradicional quilombola (BMT) foi hidrolisada e, após reação com diazometano, foi analisada por cromatografia gasosa. Dois sinais majoritários foram caracterizados por espectrometria de massas, um referente a um triterpeno de esqueleto damarânico, característico das saponinas da SAR, e outro referente ao éster metílico do ácido betulínico. Partindo das informações de uso popular da SAR, foi avaliada in vitro a atividade inibidora da acetilcolinesterase. Apesar de BMT não ter mostrado atividade neste ensaio, é possível supor que as indicações de uso desta planta pelos quilombolas como fortificante e contra malária podem estar relacionadas a uma possível atividade adaptógena e imunoestimulante, dada à presença das saponinas e do ácido betulínico em BMT.

15.
Acta amaz. ; 39(3)2009.
Artículo en Portugués | VETINDEX | ID: vti-450486

RESUMEN

This survey was conducted in the Tapajós National Forest, in the state of Pará, Brazil evaluating the cost and income of four different methods of cutting vines in the course of forest management, looking to log wood production. Each method was conducted in an area of 96 ha by cutting the vines (1) around all commercial and potentially commercial trees (Method M1), (2) only in the area of commercial and potentially commercial tree occurrence (Method M2), (3) around al commercial and potentially commercial trees and toward fall (Method M3), and (4) only around those commercial trees chosen for the first harvest (Method M4). In all variables analyzed, the methods differed statistically.Method M4 which showed the lowest cost (6.35 U.S. $), may be considered the best. In this method, the vine population was partially preserved, which is important ecologically.


Esta pesquisa foi realizada na Floresta Nacional do Tapajós, Pará, e foram avaliados os custos e rendimentos de quatro diferentes Métodos de corte de cipós na condução do manejo florestal, visando à produção de madeira em toras. Cada método foi conduzido numa área de 96 ha e a metodologia consistiu em cortar os cipós em torno de todas as árvores comerciais e potencialmente comerciais (Método M1-Individual), apenas na área de ocorrência de árvores comerciais e potencialmente comerciais (Método M2-Zoneado), em torno de todas as árvores comerciais e potencialmente comerciais e na direção de queda (Método M3-direção de queda) e apenas em torno das árvores comerciais destinadas à primeira colheita (Método M4). Em todas as variáveis analisadas os métodos utilizados diferiram estatisticamente. O método M4, com o menor custo (6,35 US$) e maior rendimento (2,07 ha/hora) é considerado o melhor desta pesquisa. Neste método, a população de cipós é parcialmente preservada, mantendo, assim, sua importante função ecológica na floresta.

16.
Acta amaz. ; 39(3)2009.
Artículo en Portugués | VETINDEX | ID: vti-450484

RESUMEN

This paper deals with the composition and structure of a pristine tropical rainforest using likelihood patterns to compare it with other Amazonian sites. This work was carried out in Alta Floresta, Mato Grosso. Our ground truth was obtained from a two-hectare plot, which was divided into 20 plots of 10 by 100 m each. In each plot, all trees with dbh = 10 cm were recorded. To evaluate the level of similarity between the Alta Floresta and other nine Amazonian sites we used the hierarchy clustering method linked by group means (UPGMA) through Sorensen index (qualitative). For ordination, we used the same method based on multidimensional non-metric scaling (NMS) through Jaccard index applied to presence or absence of botanical families or genera. The software PATN was used to run Mantel test with Jaccard index, which was, in turn, used for the similarity analysis among sites. The studied site presented 1,101 individuals distributed in 32 botanical families, 54 genera e 68 species. The richest family was Leguminosae. Helicostilys podogyne and Cecropia sp. were the most important species of the studied area. The Alta Floresta site did not present any similarity when compared to other Amazonian sites.


Este trabalho teve como objetivo estudar a composição e estrutura de um estrato arbóreo da floresta tropical úmida em Alta Floresta - MT, determinando os padrões de semelhança com outras regiões da Amazônia brasileira. O estudo foi realizado em uma área de 2 hectares, dividida em 20 parcelas de 10x 100m, onde foram mensurados a altura e o DAP 10 cm de todos os indivíduos. Para avaliação do grau de similaridade entre a composição florística e estrutura arbórea de Alta Floresta com as nove regiões pertencentes à Amazônia Legal brasileira, utilizou-se o método de agrupamento hierárquico aglomerativo com ligações pela média dos grupos (UPGMA), por meio do índice de Sorensen (qualitativo). Para a ordenação, foi utilizado o mesmo programa, utilizando a Escalonamento Multidimensional não-métrica (NMS) por meio do índice de Jaccard aplicado à presença e ausência de famílias e gêneros. Para análise de similaridade entre as 10 regiões, comparando a matriz de distâncias físicas entre elas com as matrizes de composição de famílias e gêneros, utilizou-se o programa PATN por meio do Teste de Mantel com o índice de Jaccard. A região apresentou 1101 indivíduos, pertencentes a 32 famílias, 54 gêneros e 68 espécies. A família com maior riqueza de espécie foi Leguminosae. A espécie Helicostilys podogyne e o gênero Cecropia sp. foram as mais importantes no levantamento. A floresta tropical úmida de Alta Floresta não se assemelhou com nenhuma das nove regiões comparadas neste estudo.

17.
Acta amaz ; Acta amaz;39(3)2009.
Artículo en Portugués | LILACS-Express | LILACS, VETINDEX | ID: biblio-1455004

RESUMEN

This paper deals with the composition and structure of a pristine tropical rainforest using likelihood patterns to compare it with other Amazonian sites. This work was carried out in Alta Floresta, Mato Grosso. Our ground truth was obtained from a two-hectare plot, which was divided into 20 plots of 10 by 100 m each. In each plot, all trees with dbh = 10 cm were recorded. To evaluate the level of similarity between the Alta Floresta and other nine Amazonian sites we used the hierarchy clustering method linked by group means (UPGMA) through Sorensen index (qualitative). For ordination, we used the same method based on multidimensional non-metric scaling (NMS) through Jaccard index applied to presence or absence of botanical families or genera. The software PATN was used to run Mantel test with Jaccard index, which was, in turn, used for the similarity analysis among sites. The studied site presented 1,101 individuals distributed in 32 botanical families, 54 genera e 68 species. The richest family was Leguminosae. Helicostilys podogyne and Cecropia sp. were the most important species of the studied area. The Alta Floresta site did not present any similarity when compared to other Amazonian sites.


Este trabalho teve como objetivo estudar a composição e estrutura de um estrato arbóreo da floresta tropical úmida em Alta Floresta - MT, determinando os padrões de semelhança com outras regiões da Amazônia brasileira. O estudo foi realizado em uma área de 2 hectares, dividida em 20 parcelas de 10x 100m, onde foram mensurados a altura e o DAP 10 cm de todos os indivíduos. Para avaliação do grau de similaridade entre a composição florística e estrutura arbórea de Alta Floresta com as nove regiões pertencentes à Amazônia Legal brasileira, utilizou-se o método de agrupamento hierárquico aglomerativo com ligações pela média dos grupos (UPGMA), por meio do índice de Sorensen (qualitativo). Para a ordenação, foi utilizado o mesmo programa, utilizando a Escalonamento Multidimensional não-métrica (NMS) por meio do índice de Jaccard aplicado à presença e ausência de famílias e gêneros. Para análise de similaridade entre as 10 regiões, comparando a matriz de distâncias físicas entre elas com as matrizes de composição de famílias e gêneros, utilizou-se o programa PATN por meio do Teste de Mantel com o índice de Jaccard. A região apresentou 1101 indivíduos, pertencentes a 32 famílias, 54 gêneros e 68 espécies. A família com maior riqueza de espécie foi Leguminosae. A espécie Helicostilys podogyne e o gênero Cecropia sp. foram as mais importantes no levantamento. A floresta tropical úmida de Alta Floresta não se assemelhou com nenhuma das nove regiões comparadas neste estudo.

18.
Acta amaz ; Acta amaz;39(3)2009.
Artículo en Portugués | LILACS-Express | LILACS, VETINDEX | ID: biblio-1455006

RESUMEN

This survey was conducted in the Tapajós National Forest, in the state of Pará, Brazil evaluating the cost and income of four different methods of cutting vines in the course of forest management, looking to log wood production. Each method was conducted in an area of 96 ha by cutting the vines (1) around all commercial and potentially commercial trees (Method M1), (2) only in the area of commercial and potentially commercial tree occurrence (Method M2), (3) around al commercial and potentially commercial trees and toward fall (Method M3), and (4) only around those commercial trees chosen for the first harvest (Method M4). In all variables analyzed, the methods differed statistically.Method M4 which showed the lowest cost (6.35 U.S. $), may be considered the best. In this method, the vine population was partially preserved, which is important ecologically.


Esta pesquisa foi realizada na Floresta Nacional do Tapajós, Pará, e foram avaliados os custos e rendimentos de quatro diferentes Métodos de corte de cipós na condução do manejo florestal, visando à produção de madeira em toras. Cada método foi conduzido numa área de 96 ha e a metodologia consistiu em cortar os cipós em torno de todas as árvores comerciais e potencialmente comerciais (Método M1-Individual), apenas na área de ocorrência de árvores comerciais e potencialmente comerciais (Método M2-Zoneado), em torno de todas as árvores comerciais e potencialmente comerciais e na direção de queda (Método M3-direção de queda) e apenas em torno das árvores comerciais destinadas à primeira colheita (Método M4). Em todas as variáveis analisadas os métodos utilizados diferiram estatisticamente. O método M4, com o menor custo (6,35 US$) e maior rendimento (2,07 ha/hora) é considerado o melhor desta pesquisa. Neste método, a população de cipós é parcialmente preservada, mantendo, assim, sua importante função ecológica na floresta.

19.
Acta amaz. ; 37(3)2007.
Artículo en Portugués | VETINDEX | ID: vti-450281

RESUMEN

To combine protection and utilization of forest resources in the tropics, the understanding of forest dynamics is essential. It is also important in the definition of strategies for rehabilitation of degraded areas. In Forestry, forest dynamics could be translated as the understanding of recruitment, mortality and biomass increment rates over time. For this study, these rates were estimated based on measurements carried out in 2000 and 2004 over two transects measuring 20 by 2500 m (5 hectares) each, in Manaus region. This paper deals with forest dynamics of a pristine forest based on the probabilistic transition matrix (the first-order Markov Chain) approach. The main objective is to report 4-year (2000 to 2004) changes in the forest structure. Diameter distribution and tree mortality will be projected ahead to 2008 (t+2), based upon a 4-year period of observations completed in 2004 (t+1) and its immediate past in 2000 (t). In terms of fresh aboveground biomass, this site accumulated 8.34 t.ha-1.ano-1. The chi ² test has shown no statistical difference (p = 0.01) between observed diameter frequency and the expected projected by Markov Chain. This result indicates that the Markov Chain approach is a reliable tool to project the forest dynamics on a short-term basis. In 2008, the total number of individuals will have a decrease of 2.7%, and the mortality rate will 15% higher than in 2004.


Os fatores que envolvem os processos da dinâmica da floresta influenciam a sua biodiversidade e, portanto, a qualidade da floresta. A definição de estratégias que envolve a proteção e o uso adequado da floresta manejada e a recuperação de áreas já degradadas tornam-se possível com o estudo da estrutura e dinâmica da floresta primária por meio de informações como a mortalidade, o recrutamento e a permanência das árvores no sistema florestal. Este trabalho teve como objetivo avaliar a dinâmica de uma floresta não perturbada e fazer projeções da dinâmica florestal usando a matriz de transição probabilística (Cadeia de Markov). As taxas de recrutamento, mortalidade e incremento foram determinadas a partir de inventários florestais realizados em dois transectos, nos sentidos Norte-Sul e Leste-Oeste (20 x 2500 m cada, totalizando 10 ha), localizados no km 50 da BR 174, na estrada vicinal ZF-2, Manaus/AM, nos anos de 2000 e 2004. A floresta acumulou 8,34 t.ha-1.ano-1 de biomassa fresca acima do solo. De acordo com projeção para 2008, o número total de árvores diminuirá em 2,67% (de 5987 indivíduos (2004) para 5827 (2008)) e a mortalidade será 15% maior (de 264 (2004) para 311 (2008)). O teste Qui-quadrado mostrou que não há diferença significativa (1% de probabilidade) entre as informações coletadas e projetadas. Esses resultados permitem concluir que a Cadeia de Markov é um eficiente instrumento para projetar a dinâmica da floresta natural, contribuindo para o planejamento em curto prazo das atividades que utilizam os recursos florestais.

20.
Acta amaz. ; 37(1)2007.
Artículo en Portugués | VETINDEX | ID: vti-450235

RESUMEN

In Amazonia, fire is widely used for soil preparation in the agriculture and cattle ranching, either by small or big farmers. The combination of low fertility of the soil and low price of the land usually leads to typical shift cultivation as soon as the natural sources of nutrients are exhausted, when new primary forests are felled and burned. Due to that, secondary forests originated from abandoned agriculture or pasture activity projects cover huge areas in the Brazilian Amazônia. This study was carried out in the Tropical Forestry Experimental Station (EEST/INPA), around 50 kilometers north of Manaus, the capital of Amazonas State. A secondary forest ("capoeira"), 10 years old, was selected for this study; its land use history includes clear cutting followed by fire. Two different samples of primary forests were included as control plots for the "capoeira". All individuals with diameter at breast height (DBH) greater than 5 cm were measured and recorded in a single area of 0,4 ha for each treatment. Ten years after burning, the secondary forest is still very different in comparison with primary forest, in terms of important parameters of the vegetation structure, such as floristic composition, abundance, frequency, dominance, index of value of importance (IVI) and the diameter distribution. In "capoeira" studied the dominant species are mainly of the following botanical families: Annonaceae, Arecaceae, Burseraceae, Cecropiaceae, Euphorbiaceae, Fabaceae, Lecythidaceae, Melastomataceae, Mimosaceae, Sapindaceae and Sterculiaceae. The estimates of dry biomass were 56.2 t. ha-1 ± 12 (CI 95%) and 339.7 t.ha-1 ± 66.7 (CI 95%) for "capoeira" and primary forest, respectively.


Na Amazônia, o fogo é ainda o principal trato cultural utilizado no preparo de solo para agricultura e pecuária, tanto pelos pequenos como pelos grandes fazendeiros. Combinando à baixa fertilidade do solo e ao baixo preço da terra, assim que as fontes naturais de nutrientes são exauridas, as áreas são abandonadas e novas florestas primárias são derrubadas e queimadas. Por conta disso, grandes extensões de área da Amazônia são cobertas por florestas secundárias originadas de áreas abandonadas pela agricultura ou pastagem. Este estudo foi conduzido em uma área experimental usada em uma pesquisa sobre eficiência de combustão e emissão de gás carbônico da floresta amazônica, localizada aproximadamente 50 km ao norte de Manaus. A vegetação da área experimental foi derrubada e queimada em 1991, simulando as condições em que o pequeno agricultor prepara o solo para plantios de subsistência. Dez anos após a queimada, a floresta secundária ainda é bastante diferente da floresta original. As espécies vegetais dominantes são, principalmente, das famílias botânicas Annonaceae, Arecaceae, Burseraceae, Cecropiaceae, Euphorbiaceae, Fabaceae, Lecythidaceae, Melastomataceae, Mimosaceae, Sapindaceae e Sterculiaceae. O estoque de biomassa recuperado, dez anos após a formação da capoeira estudada, é de aproximadamente 16%, ou seja, a capoeira apresenta um estoque médio de 56,2 t.ha-1 ± 12 (IC 95%), enquanto que o estoque da floresta primária é de 339,7 t.ha-1 ± 66,7 (IC 95 %).

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