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2.
Braz J Med Biol Res ; 54(4): e10766, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33624732

RESUMO

The novel Coronavirus disease (COVID-19) is responsible for thousands of deaths worldwide, especially in Brazil, currently one of the leading countries in number of infections and deaths. The beginning of the COVID-19 epidemic in Brazil is uncertain due to the low number of tests done in the country. The excess number of deaths can suggest the beginning of the pandemic in this context. In this article, we used an autoregressive integrated moving average (ARIMA) model to investigate possible excesses in the number of deaths processed by the São Paulo Autopsy Service according to different causes of deaths: all-cause, cardiovascular, and pulmonary causes. We calculated the expected number of deaths using data from 2019 to 2020 (n=17,011), and investigated different seasonal patterns using harmonic dynamic regression with Fourier terms with residuals modeled by an ARIMA method. We did not find any abnormalities in the predicted number of deaths and the real values in the first months of 2020. We found an increase in the number of deaths only by March 20, 2020, right after the first COVID-19 confirmed case in the city of São Paulo, which occurred on March 16, 2020.


Assuntos
COVID-19 , Coronavirus , Autopsia , Brasil/epidemiologia , Humanos , Pandemias , SARS-CoV-2
3.
Braz. j. med. biol. res ; 54(4): e10766, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1153540

RESUMO

The novel Coronavirus disease (COVID-19) is responsible for thousands of deaths worldwide, especially in Brazil, currently one of the leading countries in number of infections and deaths. The beginning of the COVID-19 epidemic in Brazil is uncertain due to the low number of tests done in the country. The excess number of deaths can suggest the beginning of the pandemic in this context. In this article, we used an autoregressive integrated moving average (ARIMA) model to investigate possible excesses in the number of deaths processed by the São Paulo Autopsy Service according to different causes of deaths: all-cause, cardiovascular, and pulmonary causes. We calculated the expected number of deaths using data from 2019 to 2020 (n=17,011), and investigated different seasonal patterns using harmonic dynamic regression with Fourier terms with residuals modeled by an ARIMA method. We did not find any abnormalities in the predicted number of deaths and the real values in the first months of 2020. We found an increase in the number of deaths only by March 20, 2020, right after the first COVID-19 confirmed case in the city of São Paulo, which occurred on March 16, 2020.


Assuntos
Humanos , Coronavirus , COVID-19 , Autopsia , Brasil/epidemiologia , Pandemias , SARS-CoV-2
4.
J Eur Acad Dermatol Venereol ; 34(12): 2890-2897, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32531145

RESUMO

BACKGROUND: Pemphigus herpetiformis (PH) is a rare clinical subtype of pemphigus with the presence of urticarial plaques, severe pruritus, rare acantholysis and eosinophilic spongiosis. OBJECTIVES: The aim of this study was to investigate the influence of IL-31 and pro-inflammatory cytokines/chemokines in the pathogenesis of PH. METHODS: Twenty-five patients with PH and three groups: pemphigus foliaceus (PF = 14), pemphigus vulgaris (PV = 15) and healthy controls (HC = 20) were selected for this study. The groups were analysed by immunohistochemistry utilizing IL-31, IL-31RA, IL-4, IL-17 and TNF-α antibodies. Serum levels of IL-4, IL-13, TNF, CXCL8, CCL5 and CCL2 were evaluated by cytometric bead array. RESULTS: Analysis of IL-31 family of PH patients revealed the following findings: (i) Enhanced in situ expression of IL-31 in PH samples, compared to PF and to PV (epidermis); (ii) Cutaneous IL-31RA expression in PH samples was higher than in PF, PV and HC groups (epidermis and dermis); (iii) PF patients that evolved to PH showed significant increased IL-31RA epidermal expression during the PH phase. Profile of pro-inflammatory cytokines (IL-4, IL-17 and TNF-α) in PH patients' skin exhibited: (i) Enhanced IL-4 expression, when compared to patients with PF (epidermis and dermis) and with PV (epidermis); (ii) Augmented IL-17 expression than PF and PV patients (epidermis); (iii) Augmented expression of TNF-α when compared to PF at the epidermal level. Evaluation of circulating cytokines and chemokines showed higher levels of CXCL8 and CCL2 in PH sera compared to HC group. CONCLUSIONS: IL-31 and IL-31RA, cytokines related to pruritus, and pro-inflammatory chemokines (CXCL8 and CCL2) seem to exert a role in the pathogenesis of PH. These findings support future studies to clarify the role of IL-31 pathway as a potential therapeutic target for patients with PH.


Assuntos
Doenças Autoimunes , Pênfigo , Acantólise , Quimiocina CCL2 , Citocinas , Humanos , Interleucina-13
5.
Allergol Immunopathol (Madr) ; 44(5): 439-44, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27395326

RESUMO

BACKGROUND: The prevalence of allergic diseases is increasing. We evaluated temporal trends in the prevalence of asthma, rhinitis and eczema in adolescents (13-14 years) living in Taubaté, SP, Brazil (2005-2012) and assessed the relationship between these prevalences and the residential proximity to Presidente Dutra Highway (PDH, a heavily travelled highway). METHODS: This cross-sectional study of adolescents (N=1039) from public and private schools was evaluated using the standard questionnaire of the International Study of Asthma and Allergies in Childhood (ISAAC) plus a question about their place of residence in relation to PDH. The data obtained were compared to the 2005 data using a chi-square test or Fisher's exact test. An analysis by groups consisting of two phases (two-step cluster) was used to evaluate the effect of living near PDH. RESULTS: There was a lifetime increase in the prevalence of active asthma (15.3% vs. 20.4%, p=0.005) and physician-diagnosed asthma (6.8% vs. 9.2%, p=0.06) and a decrease in the symptoms of active rhinitis (36.6% vs. 18.5%) between 2005 and 2012. A high frequency of asthma and rhinitis (18.1% vs. 23.2%, respectively) was observed among adolescents living close or very close to PDH; furthermore, 85.6% of the adolescents without symptoms of asthma or rhinitis lived far from PDH. CONCLUSION: An increase in the prevalence of asthma and a decrease in the prevalence of rhinitis were observed during the studied period. Living near PDH was associated with higher rates of asthma, rhinitis, and eczema.


Assuntos
Asma/epidemiologia , Dermatite Atópica/epidemiologia , Rinite Alérgica/epidemiologia , Adolescente , Brasil/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Prevalência , Instituições Acadêmicas , Condições Sociais/estatística & dados numéricos , Fatores Socioeconômicos , Inquéritos e Questionários , Fatores de Tempo
6.
Clin Exp Allergy ; 42(10): 1459-71, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22994343

RESUMO

BACKGROUND: Airway inflammation in asthma involves innate immune responses. Toll-like receptors (TLRs) and thymic stromal lymphopoietin (TSLP) are thought to be involved in airway inflammation, but their expression in asthmatics' both large and small airways has not been investigated. OBJECTIVE: To analyse the expression of TLR2, TLR3, TLR4 and TSLP in large and small airways of asthmatics and compare their expression in smoking and non-smoking asthmatics; to investigate whether TLR expression is associated with eosinophilic or neutrophilic airway inflammation and with Mycoplasma pneumoniae and Chlamydophila pneumoniae infection. METHODS: Using immunohistochemistry and image analysis, we investigated TLR2, TLR3, TLR4 and TSLP expression in large and small airways of 24 victims of fatal asthma, FA, (13 non-smokers, 11 smokers) and nine deceased control subjects (DCtrl). TLRs were also measured in 18 mild asthmatics (MA) and 12 healthy controls (HCtrl). M. pneumoniae and C. pneumoniae in autopsy lung tissue were analysed using real-time polymerase chain reaction. Airway eosinophils and neutrophils were measured in all subjects. RESULTS: Fatal asthma patients had higher TLR2 in the epithelial and outer layers of large and small airways compared with DCtrls. Smoking asthmatics had lower TLR2 levels in the inner and outer layers of the small airways than non-smoking asthmatics. TSLP was increased in the epithelial and outer layers of the large airways of FA. FA patients had greater TLR3 expression in the outer layer of large airways and greater TLR4 expression in the outer layer of small airways. Eosinophilic airway inflammation was associated with TLR expression in the epithelium of FA. No bacterial DNA was detected in FA or DCtrls. MA and HCtrls had only a small difference in TLR3 expression. CONCLUSIONS AND CLINICAL RELEVANCE: Increased expression of TLR 2, 3 and 4 and TSLP in fatal asthma may contribute to the acute inflammation surrounding asthma deaths.


Assuntos
Asma/mortalidade , Citocinas/metabolismo , Receptor 2 Toll-Like/metabolismo , Receptor 3 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Adulto , Asma/imunologia , Feminino , Humanos , Inflamação/imunologia , Pulmão/imunologia , Masculino , Pessoa de Meia-Idade , Regulação para Cima , Linfopoietina do Estroma do Timo
7.
Oral Dis ; 17(3): 258-64, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20860761

RESUMO

OBJECTIVE: To analyse and compare the expression of Palate, Lung, and Nasal Epithelium Clone (PLUNC) proteins in salivary glands from patients with and without AIDS (control group) using autopsy material. METHODS: We analysed the expression of PLUNCs using immunohistochemistry in parotid (n = 45), submandibular (n = 47) and sublingual gland (n = 37) samples of AIDS patients [30 with normal histology, 21 with mycobacteriosis, 14 with cytomegalovirus (CMV) infection, 30 with chronic non-specific sialadenitis, and 30 HIV-negative controls. In situ hybridization (ISH) for SPLUNC 2 in the HIV-negative group was performed. RESULTS: SPLUNC 1 expression was detected in the mucous acini of submandibular and sublingual glands, and SPLUNC 2 were seen in the serous cells. LPLUNC 1 expression was only positive in the salivary ducts. There was a higher expression of SPLUNC 2 in AIDS patients with CMV infection and mycobacteriosis when compared with all other groups. The intensity of staining for SPLUNC 2 was greater around the lesions than the peripheral ones. ISH for SPLUNC 2 showed perinuclear positivity in the serous cells in all HIV-negative cases. CONCLUSIONS: SPLUNC 1 and LPLUNC 1 proteins were similarly expressed in the salivary glands of AIDS patients and non-HIV patients. CMV infection and mycobacteriosis increase SPLUNC 2 expression in serous cells in the salivary gland of AIDS patients.


Assuntos
Síndrome de Imunodeficiência Adquirida/patologia , Glicoproteínas/análise , Fosfoproteínas/análise , Glândulas Salivares/patologia , Infecções Oportunistas Relacionadas com a AIDS/patologia , Adolescente , Adulto , Idoso , Infecções por Citomegalovirus/patologia , Feminino , Soronegatividade para HIV , Humanos , Imuno-Histoquímica , Hibridização In Situ , Masculino , Pessoa de Meia-Idade , Doenças Parotídeas/patologia , Glândula Parótida/patologia , Ductos Salivares/patologia , Doenças das Glândulas Salivares/patologia , Membrana Serosa/patologia , Sialadenite/patologia , Glândula Sublingual/patologia , Glândula Submandibular/patologia , Doenças da Glândula Submandibular/patologia , Tuberculose Bucal/patologia , Adulto Jovem
8.
Clin Exp Allergy ; 40(10): 1473-81, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20937062

RESUMO

BACKGROUND: IgE and its high-affinity receptor FcɛRI play an important role in allergy and asthma. The distribution of FcɛRI expression in the airways and within the airway wall, however, is largely unknown. OBJECTIVE: In this study, we aimed to map the distribution of FcɛRI in different layers of large airways (LA) and small airways (SA) in lung tissue from non-smoking and smoking patients who died of asthma [fatal asthma (FA)] and non-smoking controls (CTR). METHODS: Postmortem lung tissue from 24 cases of non-smoking FA, 13 smoking FA patients and from 19 subjects who died of non-pulmonary causes (CTR) was immunohistochemically stained for FcɛRI and AA1 (mast cell tryptase marker). The expression of these markers was analysed in inner, muscle, and outer layers of both LA and SA by image analysis. RESULTS: FcɛRI expression was higher in non-smoking and smoking FA compared with CTR in the inner and outer layer of SA. In the outer layer of LA, FcɛRI expression was higher in non-smoking FA compared with CTR. AA1 was higher in non-smoking FA compared with smoking FA and CTR in the outer layer of the SA, which was correlated with FcɛRI in this layer. CONCLUSION: Our results show that the expression of FcɛRI is higher in both LA and SA in FA compared with CTR. These differences are predominantly found in the outer layer where they can be attributed in part to the increased mast cell numbers. These results indicate an increased capacity to mount IgE-mediated reactions in FA, both in LA and SA.


Assuntos
Asma/imunologia , Brônquios/imunologia , Receptores de IgE/biossíntese , Adulto , Asma/metabolismo , Autopsia , Brônquios/metabolismo , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Masculino , Mastócitos/imunologia , Pessoa de Meia-Idade , Triptases/biossíntese
9.
Ann Oncol ; 21(12): 2333-2341, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20511340

RESUMO

BACKGROUND: The natural history and consequences of severe H1N1 influenza infection among cancer patients are not yet fully characterized. We describe eight cases of H1N1 infection in cancer patients admitted to the intensive care unit of a referral cancer center. PATIENTS AND METHODS: Clinical data from all patients admitted with acute respiratory failure due to novel viral H1N1 infection were reviewed. Lung tissue was submitted for viral and bacteriological analyses by real-time RT-PCR, and autopsy was conducted on all patients who died. RESULTS: Eight patients were admitted, with ages ranging from 55 to 65 years old. There were five patients with solid organ tumors (62.5%) and three with hematological malignancies (37.5%). Five patients required mechanical ventilation and all died. Four patients had bacterial bronchopneumonia. All deaths occurred due to multiple organ failure. A milder form of lung disease was present in the three cases who survived. Lung tissue analysis was performed in all patients and showed diffuse alveolar damage in most patients. Other lung findings were necrotizing bronchiolitis or extensive hemorrhage. CONCLUSIONS: H1N1 viral infection in patients with cancer can cause severe illness, resulting in acute respiratory distress syndrome and death. More data are needed to identify predictors of unfavorable evolution in these patients.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Influenza Humana/complicações , Neoplasias/complicações , Idoso , Autopsia , Feminino , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/fisiologia , Influenza Humana/diagnóstico por imagem , Influenza Humana/mortalidade , Influenza Humana/patologia , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/etiologia , Insuficiência de Múltiplos Órgãos/patologia , Neoplasias/diagnóstico por imagem , Neoplasias/mortalidade , Neoplasias/patologia , Radiografia , Respiração Artificial , Síndrome do Desconforto Respiratório/diagnóstico por imagem , Síndrome do Desconforto Respiratório/etiologia , Síndrome do Desconforto Respiratório/mortalidade , Síndrome do Desconforto Respiratório/patologia , Estudos Retrospectivos , Índice de Gravidade de Doença
10.
Clin Exp Allergy ; 39(10): 1499-507, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19486035

RESUMO

BACKGROUND: To date, little information has been available about pulmonary artery pathology in asthma. The pulmonary artery supplies the distal parts of the lungs and likely represents a site of immunological reaction in allergic inflammation. The objective of this study was to describe the inflammatory cell phenotype of pulmonary artery adventitial inflammation in lung tissue from patients who died of asthma. METHODS: We quantified the different inflammatory cell types in the periarterial region of small pulmonary arteries in lung tissue from 22 patients who died of asthma [fatal asthma (FA)] and 10 control subjects. Using immunohistochemistry and image analysis, we quantified the cell density for T lymphocytes (CD3, CD4, CD8), B lymphocytes (CD20), eosinophils, mast cells (chymase and tryptase), and neutrophils in the adventitial layer of pulmonary arteries with a diameter smaller than 500 microm. RESULTS: Our data (median/interquartile range) demonstrated increased cell density of mast cells [FA=271.8 (148.7) cells/mm2; controls=177.0 (130.3) cells/mm2, P=0.026], eosinophils [FA=23.1 (58.6) cells/mm2; controls=0.0 (2.3) cells/mm2, P=0.012], and neutrophils [FA=50.4 (85.5) cells/mm2; controls=2.9 (30.5) cells/mm2, P=0.009] in the periarterial space in FA. No significant differences were found for B and T lymphocytes or CD4+ or CD8+ subsets. Chymase/tryptase positive (MCCT) mast cells predominated over tryptase (MCT) mast cells in the perivascular arterial space in both asthma patients and controls [MCCT/(MCCT+MCT)=0.91 (0-1) in FA and 0.75 (0-1) in controls, P=0.86]. CONCLUSIONS: Our results show that the adventitial layer of the pulmonary artery participates in the inflammatory process in FA, demonstrating increased infiltration of mast cells, eosinophils, and neutrophils, but not of T and B lymphocytes.


Assuntos
Arterite/metabolismo , Asma/metabolismo , Pulmão/metabolismo , Mastócitos/metabolismo , Artéria Pulmonar/metabolismo , Adolescente , Adulto , Idoso , Antígenos CD/metabolismo , Arterite/mortalidade , Arterite/patologia , Asma/mortalidade , Asma/patologia , Criança , Quimases/metabolismo , Feminino , Humanos , Inflamação/metabolismo , Inflamação/mortalidade , Inflamação/patologia , Leucócitos/metabolismo , Leucócitos/patologia , Pulmão/irrigação sanguínea , Pulmão/patologia , Masculino , Mastócitos/patologia , Pessoa de Meia-Idade , Artéria Pulmonar/patologia , Estudos Retrospectivos , Triptases/metabolismo
11.
Eur Respir J ; 32(1): 61-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18321931

RESUMO

There is an intimate relationship between the extracellular matrix (ECM) and smooth muscle cells within the airways. Few studies have comprehensively assessed the composition of different ECM components and its regulators within the airway smooth muscle (ASM) in asthma. With the aid of image analysis, the fractional areas of total collagen and elastic fibres were quantified within the ASM of 35 subjects with fatal asthma (FA) and compared with 10 nonfatal asthma (NFA) patients and 22 nonasthmatic control cases. Expression of collagen I and III, fibronectin, versican, matrix metalloproteinase (MMP)-1, -2, -9 and -12 and tissue inhibitor of metalloproteinase-1 and -2 was quantified within the ASM in 22 FA and 10 control cases. In the large airways of FA cases, the fractional area of elastic fibres within the ASM was increased compared with NFA and controls. Similarly, fibronectin, MMP-9 and MMP-12 were increased within the ASM in large airways of FA cases compared with controls. Elastic fibres were increased in small airways in FA only in comparison with NFA cases. There is altered extracellular matrix composition and a degradative environment within the airway smooth muscle in fatal asthma patients, which may have important consequences for the mechanical and synthetic functions of airway smooth muscle.


Assuntos
Asma/metabolismo , Matriz Extracelular/metabolismo , Metaloproteinases da Matriz/metabolismo , Músculo Liso/metabolismo , Inibidores Teciduais de Metaloproteinases/metabolismo , Adolescente , Adulto , Asma/patologia , Brônquios/metabolismo , Brônquios/patologia , Estudos de Casos e Controles , Matriz Extracelular/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Liso/patologia
12.
Oral Dis ; 14(1): 82-8, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18173453

RESUMO

OBJECTIVE: Secretory leukocyte proteinase inhibitor (SLPI) is an endogenous proteinase inhibitor present in mucosal secretions. It also displays antimicrobial activity including anti-human immunodeficiency virus activity. This protease inhibitor is also expressed in submandibular glands (SMG), but there are few data on its expression in AIDS patients with infectious conditions. METHODS: We analyzed the expression of SLPI using immunohistochemistry in submandibular gland samples of 36 AIDS patients [10 with normal histology, 10 with chronic nonspecific sialadenitis, eight with mycobacteriosis, and eight with cytomegalovirus (CMV) infection] and 10 HIV-negative controls. The proteinase inhibitor was quantified using image analysis and expressed as % of positively stained area. RESULTS: There was a higher expression of SLPI in AIDS patients with CMV infection (% of stained area, mean+/-SD: 37.37+/-14.45) when compared with all other groups (P=0.009). There were no significant differences between control subjects (22.70+/-9.42%) and AIDS patients without histologic alterations (18.10+/-7.58%), with chronic nonspecific sialadenitis (17.13+/-5.36%), or mycobacterial infection (21.09+/-4.66%). CONCLUSION: Cytomegalovirus infection increases SLPI expression in the SMG of AIDS patients. Our results reveal new insights into the pathogenic association between HIV and CMV in AIDS patients.


Assuntos
Síndrome de Imunodeficiência Adquirida/patologia , Inibidor Secretado de Peptidases Leucocitárias/análise , Glândula Submandibular/patologia , Infecções Oportunistas Relacionadas com a AIDS/patologia , Adulto , Idoso , Causas de Morte , Doença Crônica , Infecções por Citomegalovirus/patologia , Feminino , Soronegatividade para HIV , Humanos , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Infecções por Mycobacterium/patologia , Sialadenite/patologia , Doenças da Glândula Submandibular/patologia
13.
Braz. j. biol ; 67(4): 673-680, Nov. 2007. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-474191

RESUMO

The carbon (C) concentration and flux, as dissolved organic carbon (DOC), particulate organic carbon (POC) and macrodetritus (MD), were quantified through 4 tidal cycles in a mangrove tidal creek in Southeastern Brazil. DOC was the major fraction of the total C concentration, accounting for 68 and 61 percent of the total C concentration during ebb and flood periods respectively. Concentrations of DOC (Ebb = 3,41 ± 0,57 mgC.L-1 and Flood = 3,55 ± 0,76 mgC.L-1) and POC (Ebb = 1,73 ± 0,99 mgC.L-1 and Flood = 1,28 ± 0,45 mgC.L-1) were relatively similar during the four tidal cycles. Macrodetritus presented a wide variation with concentration peaks probably related to external forces, such as winds, which enrich the ebb flow with leaf litter. DOC and POC fluxes depended primarily on tidal and net water fluxes, whereas MD fluxes were not. The magnitude of the DOC and POC fluxes varied with the area flooded at high tide, but not the MD fluxes. DOC was the major form of carbon export to Sepetiba Bay. During the four tidal cycles, the forest exported a total of 1,2 kg of organic carbon per ha, mostly as DOC (60 percent), followed by POC (22 percent) and MD (18 percent).


As concentrações e fluxos de carbono orgânico sob forma de carbono orgânico dissolvido (COD), carbono orgânico particulado (COP) e macrodetritos (MD) foram quantificadas durante 4 ciclos de maré em canal de maré na Floresta Experimental de Itacuruçá, Baía de Sepetiba, RJ, litoral sudeste do Brasil. COD foi a fração mais importante para a concentração total de carbono orgânico, contribuindo com 68 e 61 por cento da concentração total de C nos períodos de maré vazante e enchente, respectivamente. As concentrações de COD (vazante = 3.41 ± 0.57 mgC.L-1 e enchente = 3.55 ± 0.76 mgC.L-1) e COP (vazante = 1.73 ± 0.99 mgC.L-1 e enchente = 1.28 ± 0.45 mgC.L-1) foram similares durante os 4 ciclos de maré. A fração macrodetritos apresentou uma ampla variabilidade com máximos de concentração relacionados a fatores externos como ventos, que enriqueceram as águas de vazante com macrodetritos. A magnitude dos fluxos de COD e COP, mas não os de macrodetritos, relacionaram-se com os fluxos de água e a conseqüente área inundada pela maré. A fração COD foi a mais importante forma de exportação de carbono orgânico pelo manguezal. Durante os 4 ciclos monitorados, a floresta exportou um total de 1.2 kg de carbono orgânico, 60 por cento sob forma de COD, seguido pelo COP (22 por cento) e pela fração macrodetritos (18 por cento).


Assuntos
Avicennia/metabolismo , Carbono/metabolismo , Combretaceae/metabolismo , Sedimentos Geológicos/análise , Rhizophoraceae/metabolismo , Brasil , Carbono/análise , Água do Mar/análise
14.
Braz J Biol ; 67(4): 673-80, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18278319

RESUMO

The carbon (C) concentration and flux, as dissolved organic carbon (DOC), particulate organic carbon (POC) and macrodetritus (MD), were quantified through 4 tidal cycles in a mangrove tidal creek in Southeastern Brazil. DOC was the major fraction of the total C concentration, accounting for 68 and 61% of the total C concentration during ebb and flood periods respectively. Concentrations of DOC (Ebb = 3.41 +/- 0.57 mgC.L-1 and Flood = 3.55 +/- 0.76 mgC.L-1) and POC (Ebb = 1.73 +/- 0.99 mgC.L-1 and Flood = 1.28 +/- 0.45 mgC.L-1) were relatively similar during the four tidal cycles. Macrodetritus presented a wide variation with concentration peaks probably related to external forces, such as winds, which enrich the ebb flow with leaf litter. DOC and POC fluxes depended primarily on tidal and net water fluxes, whereas MD fluxes were not. The magnitude of the DOC and POC fluxes varied with the area flooded at high tide, but not the MD fluxes. DOC was the major form of carbon export to Sepetiba Bay. During the four tidal cycles, the forest exported a total of 1.2 kg of organic carbon per ha, mostly as DOC (60%), followed by POC (22%) and MD (18%).


Assuntos
Avicennia/metabolismo , Carbono/metabolismo , Combretaceae/metabolismo , Sedimentos Geológicos/análise , Rhizophoraceae/metabolismo , Brasil , Carbono/análise , Água do Mar/análise
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