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1.
Acta cir. bras ; 38: e382923, 2023. tab, graf, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1505463

Resumo

Purpose: To explore effect and mechanism of olsalazine of Chinese generic drugs on ulcerative colitis induced by dextran sulfate sodium salt (DSS) in BALB/c mice. Methods: The mouse model of ulcerative colitis was induced by free drinking of 3% (w/v) DSS aqueous solution for seven days. The mice were treated with olsalazine (0.6 g·kg-1) of Chinese generic drugs. The therapeutic effect of olsalazine on ulcerative colitis mice was evaluated by measuring disease activity index (DAI), colonic mucosal injury index (CMDI), histopathological score (HS), and detected the expression levels of interleukin (IL)-2, IL-10, tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), IL-1ß in serum and IL-7, IL-17, IL-22, epidermal growth factor (EGF), transforming growth factor ß1 (TGF-ß1) in colonic homogenate of mice. Results: Olsalazine significantly increased the contents of IL-2, IL-10, IL-22, TGF and EGF in ulcerative colitis rats, and significantly decreased the scores of DAI, CMDI, HS and the contents in IL-7, IL-17, TNF-α, IL-1ß and IFN-γ when compared with the model group. It improved the degree of colonic lesion in ulcerative colitis mice. Conclusions: It was suggested that olsalazine has a therapeutic effect on ulcerative colitis induced by DSS in mice, and the mechanism may be related to the increase of IL-2, IL-10, IL-22, TGF, and EGF and the decrease of the expression of IL-7, IL-17, TNF-α, IL-1ß, and IFN-γ.


Assuntos
Animais , Camundongos , Colite Ulcerativa/tratamento farmacológico , Sulfato de Dextrana , Medicamentos Genéricos
2.
Acta cir. bras ; 38: e381523, 2023. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1439109

Resumo

Purpose: It was aimed to investigate the biochemical and immunohistochemical effects of ephedrine (EPH) in bilateral ovariectomized rats. Methods: Twenty-four Sprague Dawley female rats were divided into three groups: control group: The abdomen was opened and closed without any treatment; ischemia-reperfusion (IR) group: 2 h of ischemia followed by 2 h of reperfusion were allowed to cause IR injury; IR+EPH group: oral EPH solution (5 mg/kg) was administered for 28 days. Results: Biochemical parameters were statistically significant in group comparisons. Increased interleukin-6 (IL-6) expression, degenerative preantral and antral follicle cells and inflammatory cells around blood vessels were seen in IR group. Negative IL-6 expression was observed in seminal epithelial cells, preantral and antral follicle cells in IR+EPH group. While caspase-3 activity increased in granulosa cells and stromal cells in IR group, caspase-3 expression was negative in preantral and antral follicle cells in the germinal epithelium and cortex in IR+EPH group. Conclusion: The effect of apoptosis, which occurs with the signaling that starts in the cell nucleus, caused the cessation of the stimulating effect at the nuclear level after EPH administration, and a decrease in the antioxidative effect in IR damage and inflammation in the apoptotic process.


Assuntos
Animais , Feminino , Ratos , Ovário/citologia , Interleucina-6/fisiologia , Efedrina/análise , Caspase 3/fisiologia , Imuno-Histoquímica , Ratos Sprague-Dawley , Apoptose
3.
Acta sci. vet. (Impr.) ; 51: Pub. 1923, 2023. tab
Artigo em Inglês | VETINDEX | ID: biblio-1444000

Resumo

Background: Anaplasmosis, also called gall sickness or tropical bovine ehrlichiosis, is an infectious disease caused by species belonging to the genus Anaplasma in domestic and wild animals in tropical and subtropical regions. Anaplasma ovis and A. phagocytophilum are important pathogens of sheep. A. ovis is considered the most common species affecting sheep. The infection is usually subclinical and progresses with high fever, anaemia, icterus, weight loss and abortions. This study aimed to investigate changes in cardiac damage markers, oxidative stress and antioxidant status, cytokines, and acute phase proteins in sheep naturally infected with A. ovis. Materials, Methods & Results: For this purpose, a total of 40 animals, including 20 healthy sheep and 20 sheep infected with anaplasmosis, were used. A. ovis was diagnosed based on clinical findings and peripheral blood smear. Blood smears were prepared from the ear vein. The smears were stained with Giemsa and examined for the presence of Anaplasma spp. Infection was also confirmed by polymerase chain reaction (PCR) analysis. The genomic DNA was isolated from blood, and the MSP-4 gene region was amplified as A. ovis specific target gene. Twenty clinically healthy sheep of the same age group, reared under the same conditions and testing negative in the molecular assessment were used as controls. Blood samples were collected from the cephalic vein and and centrifuged to obtain serum. The serum stored at -20°C until the analysis stage. Serum samples were used for the analysis of cardiac damage markers [troponin I (cTnI), creatine kinase MB (CK-MB), lactate dehydrogenase (LDH) and aspartate transaminase (AST)], oxidative stress parameters [malondialdehyde (MDA), total antioxidant status (TAS), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx)], cytokines [interleukins IL-6, IL-1ß and IL-10, tumour necrosis factor α (TNF-α), and interferon-γ (IFN-γ)] and acute phase proteins [C-reactive protein (CRP), serum amyloid A (SAA) and haptoglobin (Hp)]. cTnI and CK-MB levels were measured using a chemiluminescent immunoassay. MDA, TAS, SOD, CAT, GPx, TNF-α, IL-1ß, IL-6, IL-10, IFN-γ, SAA and Hp levels were measured by an ELISA reader. LDH, AST and CRP levels were measured in an autoanalyzer. cTnI and LDH levels were significantly increased in the infected animals compared to the healthy ones (P < 0.05). The concentration of AST was decreased in infected animals. MDA, TAS, SOD, CAT and GPx levels were significantly increased in the infected animals compared to the healthy ones (P < 0.05). The levels of the inflammatory parameters such as TNF-α, IL-1ß, IL-10 and IFN-γ were significantly increased in the infected animals compared to the healthy ones (P < 0.05). Hp level were significantly increased in the infected group compared with the control group (P < 0.05). However, there was no significant change in CK-MB, SAA and CRP concentrations in the infected animals (P > 0.05). Discussion: Ovine anaplasmosis is an obligate intracellular arthropod disease that causes widespread changes in haematobiochemical, immune response and oxidative stress parameters. Cardiac damage is often overlooked in field conditions due to the lack of adequate knowledge about the pathophysiology of the disease. Our results showed that A. ovis infection leads to significant changes in cardiac biomarkers and that the parasite can cause cardiac dysfunction. This is the first report on cardiac damage markers in Anaplasma-infected sheep. Additionally, the levels of proinflammatory and oxidative stress markers that may cause functional disorders were also found to be increased. Thus, measuring markers of cardiac function, oxidative stress and inflammation can be a useful tool in the early diagnosis of ovine anaplasmosis.


Assuntos
Animais , Ovinos , Citocinas/análise , Estresse Oxidativo , Anaplasma ovis/isolamento & purificação , Testes de Função Cardíaca/veterinária , Anaplasmose/diagnóstico , Proteínas de Fase Aguda/análise
4.
J. venom. anim. toxins incl. trop. dis ; 29: e20220044, 2023. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1418314

Resumo

Background: Propolis exhibits huge potential in the pharmaceutical industry. In the present study, its effects were investigated on dendritic cells (DCs) stimulated with a tumor antigen (MAGE-1) and retinoic acid (RA) and on T lymphocytes to observe a possible differential activation of T lymphocytes, driving preferentially to Th1 or Treg cells. Methods: Cell viability, lymphocyte proliferation, gene expression (T-bet and FoxP3), and cytokine production by DCs (TNF-α, IL-10, IL-6 and IL-1ß) and lymphocytes (IFN-γ and TGF-ß) were analyzed. Results: MAGE-1 and RA alone or in combination with propolis inhibited TNF-α production and induced a higher lymphoproliferation compared to control, while MAGE1 + propolis induced IL-6 production. Propolis in combination with RA induced FoxP3 expression. MAGE-1 induced IFN-γ production while propolis inhibited it, returning to basal levels. RA inhibited TGF-ß production, what was counteracted by propolis. Conclusion: Propolis affected immunological parameters inhibiting pro-inflammatory cytokines and favoring the regulatory profile, opening perspectives for the control of inflammatory conditions.(AU)


Assuntos
Própole/efeitos adversos , Células Dendríticas/química , Anti-Inflamatórios/efeitos adversos , Tretinoína/análise , Linfócitos T , Células Th1/efeitos dos fármacos
5.
Braz. j. biol ; 822022.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468623

Resumo

Abstract Plectranthus barbatus Andrews (Lamiaceae) is widely distributed in the world and has a range of popular therapeutic indications. This work aimed to evaluate the phytochemical characterization of two leaf extracts of P. barbatus, and their antimicrobial, antineoplastic and immunomodulatory potential. After collection, herborization and obtainment of the P. barbatus aqueous extract (PBA) and acetone:water 7:3 P. barbatus organic extract (PBO), the phytochemical characterization was performed by high-performance liquid chromatography (HPLC). The antimicrobial activity was performed to determine the minimum inhibitory concentration (MIC) against eight bacterial strains using the microdilution test and the fungus Trichophyton rubrum by disc diffusion assay and microdilution test. Cytotoxicity was assessed by MTT and trypan blue methods in normal peripheral blood mononuclear cells (PBMCs) at concentrations ranged between 0.1 to 100 µg.mL-1 and in neoplastic cell lines Toledo, K562, DU-145 and PANC-1 at 1, 10 and 100 µg.mL-1 . Immunomodulatory activity, was evaluated by sandwich ELISA of proinflammatory cytokines at BALB/c mice splenocytes cultures supernatant. Both extracts presented flavonoids, cinnamic derivatives, steroids and ellagic acid. PBO showed bacteriostatic activity against Acinetobacter baumannii (MIC = 250 µg.mL-1) clinical isolate and PBA fungistatic activity against Trichophyton rubrum (MIC = 800 µg.mL-1). The extracts did not exhibit toxicity to PBMCs and neoplastic cells (IC50 > 100 µg.mL-1). Additionally, PBO at 100 µg.mL-1 significantly inhibited IFN- and IL-17A cytokines (p = 0.03). Plectranthus barbatus is a potential candidate for therapeutic use due to its low toxicity in healthy human cells and exhibits biological activities of medical interest as bacteriostatic, fungistatic and immunomodulatory.


Resumo Plectranthus barbatus Andrews (Lamiaceae) é amplamente distribuída no mundo e com uma série de indicações terapêuticas populares. Este trabalho teve como objetivo avaliar a caracterização fitoquímica de dois extratos da folha de P. barbatus e seu potencial antimicrobiano, antineoplásico e imunomodulador. Após coleta, herborização e obtenção do extrato aquoso (PBA) e acetona: água 7: 3 (orgânico) (PBO) de P. barbatus, a caracterização fitoquímica foi realizada por cromatografia líquida de alta eficiência (CLAE). A atividade antimicrobiana foi realizada para determinar a concentração inibitória mínima (CIM) contra oito cepas bacterianas usando o teste de microdiluição e o fungo Trichophyton rubrum por ensaio de difusão em disco e teste de microdiluição. A citotoxicidade foi avaliada por métodos MTT e azul de tripan em células normais mononucleares do sangue periférico (CMSP) em concentrações variadas entre 0,1 a 100 µg.mL-1 e nas linhagens celulares neoplásicas Toledo, K562, DU-145 e PANC-1 em 1, 10 e 100 µg.mL-1 . A atividade imunomoduladora foi avaliada por ELISA sanduíche de citocinas pró-inflamatórias em sobrenadante de culturas de esplenócitos de camundongos BALB/c. Ambos os extratos apresentaram flavonoides, derivados cinâmicos, esteróides e ácido elágico. O PBO mostrou atividade bacteriostática contra Acinetobacter baumannii (CIM = 250 µg.mL-1) e atividade fungistática do PBA contra Trichophyton rubrum (CIM = 800 µg.mL-1). Os extratos não apresentaram toxicidade para CMSP e células neoplásicas (IC50 > 100 µg.mL-1). Além disso, o PBO a 100 µg.mL-1 inibiu significativamente as citocinas IFN- e IL-17A (p = 0,03). Plectranthus barbatus é um candidato potencial para uso terapêutico devido à sua baixa toxicidade em células humanas saudáveis e exibe atividade de interesse médico como bacteriostática, fungistática e imunomoduladora.

6.
Acta sci., Anim. sci ; 44: e56477, 2022. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1380107

Resumo

The study determined immunological indices of Giant African Land snail (Archachatina marginata) improved with fixed dose of vitamin C under acute heat stress (AHS). Prior to the AHS, vitamin C was administered for four weeks to two treatment groups, while other two treatment groups were not. Each treatment was monitored, haemolymph collected at 0, 30 and 60 minutes exposure times. Immunological cytokines: interferon gamma (IFN-γ) and interleukin 2 (IL-2); and total haemocyte counts (THC) were determined. Under AHS, vitamin C elevated (p <0.05) IFN-γ production (606.33 ± 302.86) compared to other groups with or without vitamin C administration (7.20 ± 1.58 vs. 73.20 ± 32.23 vs. 7.80 ± 1.36). IL-2 was not affected (p >0.05) by vitamin C under AHS. Highest (p <0.05) THC values was obtained with vitamin C administration under AHS, but reduced under no AHS. Exposure time affected (p <0.05) IFN-γ production and THC values, but not IL-2 (p >0.05). With fixed dose of vitamin C and exposure time, highest (p <0.05) IFN-γ values were obtained under AHS with vitamin C administration at 30 minutes and at 60 minutes in THC, compared to other groups. The study concluded that fixed dose of vitamin C at 150 mg kg-1 of feed was appropriate under AHS to boost the immune system of the animals.(AU)


Assuntos
Animais , Ácido Ascórbico/administração & dosagem , Caramujos/imunologia , Relação Dose-Resposta Imunológica , Alimentos Fortificados , Técnicas Imunológicas/veterinária , Interleucinas/imunologia , Interferons/imunologia , Resposta ao Choque Térmico/fisiologia , Hemócitos/imunologia
7.
Braz. j. biol ; 82: 1-12, 2022. graf, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468436

Resumo

Plectranthus barbatus Andrews (Lamiaceae) is widely distributed in the world and has a range of popular therapeutic indications. This work aimed to evaluate the phytochemical characterization of two leaf extracts of P. barbatus, and their antimicrobial, antineoplastic and immunomodulatory potential. After collection, herborization and obtainment of the P. barbatus aqueous extract (PBA) and acetone:water 7:3 P. barbatus organic extract (PBO), the phytochemical characterization was performed by high-performance liquid chromatography (HPLC). The antimicrobial activity was performed to determine the minimum inhibitory concentration (MIC) against eight bacterial strains using the microdilution test and the fungus Trichophyton rubrum by disc diffusion assay and microdilution test. Cytotoxicity was assessed by MTT and trypan blue methods in normal peripheral blood mononuclear cells (PBMCs) at concentrations ranged between 0.1 to 100 µg.mL-¹ and in neoplastic cell lines Toledo, K562, DU-145 and PANC-1 at 1, 10 and 100 µg.mL-¹ . Immunomodulatory activity, was evaluated by sandwich ELISA of proinflammatory cytokines at BALB/c mice splenocytes cultures supernatant. Both extracts presented flavonoids, cinnamic derivatives, steroids and ellagic acid. PBO showed bacteriostatic activity against Acinetobacter baumannii (MIC = 250 µg.mL-¹) clinical isolate and PBA fungistatic activity against Trichophyton rubrum (MIC = 800 µg.mL-¹). The extracts did not exhibit toxicity to PBMCs and neoplastic cells (IC50 > 100 µg.mL-¹). Additionally, PBO at 100 µg.mL-1 significantly inhibited IFN-γ and IL-17A cytokines (p = 0.03). Plectranthus barbatus is a potential candidate for therapeutic use due to its low toxicity in healthy human cells and exhibits biological activities of medical interest as bacteriostatic, fungistatic and immunomodulatory.


Plectranthus barbatus Andrews (Lamiaceae) é amplamente distribuída no mundo e com uma série de indicações terapêuticas populares. Este trabalho teve como objetivo avaliar a caracterização fitoquímica de dois extratos da folha de P. barbatus e seu potencial antimicrobiano, antineoplásico e imunomodulador. Após coleta, herborização e obtenção do extrato aquoso (PBA) e acetona: água 7: 3 (orgânico) (PBO) de P. barbatus, a caracterização fitoquímica foi realizada por cromatografia líquida de alta eficiência (CLAE). A atividade antimicrobiana foi realizada para determinar a concentração inibitória mínima (CIM) contra oito cepas bacterianas usando o teste de microdiluição e o fungo Trichophyton rubrum por ensaio de difusão em disco e teste de microdiluição. A citotoxicidade foi avaliada por métodos MTT e azul de tripan em células normais mononucleares do sangue periférico (CMSP) em concentrações variadas entre 0,1 a 100 µg.mL-¹ e nas linhagens celulares neoplásicas Toledo, K562, DU-145 e PANC-¹ em 1, 10 e 100 µg.mL-¹ . A atividade imunomoduladora foi avaliada por ELISA sanduíche de citocinas pró-inflamatórias em sobrenadante de culturas de esplenócitos de camundongos BALB/c. Ambos os extratos apresentaram flavonoides, derivados cinâmicos, esteróides e ácido elágico. O PBO mostrou atividade bacteriostática contra Acinetobacter baumannii (CIM = 250 µg.mL-¹) e atividade fungistática do PBA contra Trichophyton rubrum (CIM = 800 µg.mL-¹). Os extratos não apresentaram toxicidade para CMSP e células neoplásicas (IC50 > 100 µg.mL-¹). Além disso, o PBO a 100 µg.mL-¹ inibiu significativamente as citocinas IFN-γ e IL-17A (p = 0,03). Plectranthus barbatus é um candidato potencial para uso terapêutico devido à sua baixa toxicidade em células humanas saudáveis e exibe atividade de interesse médico como bacteriostática, fungistática e imunomoduladora.


Assuntos
Fitoterapia , Plantas Medicinais/química , Plectranthus/química
8.
Braz. J. Biol. ; 82: 1-12, 2022. graf, tab
Artigo em Inglês | VETINDEX | ID: vti-31771

Resumo

Plectranthus barbatus Andrews (Lamiaceae) is widely distributed in the world and has a range of popular therapeutic indications. This work aimed to evaluate the phytochemical characterization of two leaf extracts of P. barbatus, and their antimicrobial, antineoplastic and immunomodulatory potential. After collection, herborization and obtainment of the P. barbatus aqueous extract (PBA) and acetone:water 7:3 P. barbatus organic extract (PBO), the phytochemical characterization was performed by high-performance liquid chromatography (HPLC). The antimicrobial activity was performed to determine the minimum inhibitory concentration (MIC) against eight bacterial strains using the microdilution test and the fungus Trichophyton rubrum by disc diffusion assay and microdilution test. Cytotoxicity was assessed by MTT and trypan blue methods in normal peripheral blood mononuclear cells (PBMCs) at concentrations ranged between 0.1 to 100 µg.mL-¹ and in neoplastic cell lines Toledo, K562, DU-145 and PANC-1 at 1, 10 and 100 µg.mL-¹ . Immunomodulatory activity, was evaluated by sandwich ELISA of proinflammatory cytokines at BALB/c mice splenocytes cultures supernatant. Both extracts presented flavonoids, cinnamic derivatives, steroids and ellagic acid. PBO showed bacteriostatic activity against Acinetobacter baumannii (MIC = 250 µg.mL-¹) clinical isolate and PBA fungistatic activity against Trichophyton rubrum (MIC = 800 µg.mL-¹). The extracts did not exhibit toxicity to PBMCs and neoplastic cells (IC50 > 100 µg.mL-¹). Additionally, PBO at 100 µg.mL-1 significantly inhibited IFN-γ and IL-17A cytokines (p = 0.03). Plectranthus barbatus is a potential candidate for therapeutic use due to its low toxicity in healthy human cells and exhibits biological activities of medical interest as bacteriostatic, fungistatic and immunomodulatory.(AU)


Plectranthus barbatus Andrews (Lamiaceae) é amplamente distribuída no mundo e com uma série de indicações terapêuticas populares. Este trabalho teve como objetivo avaliar a caracterização fitoquímica de dois extratos da folha de P. barbatus e seu potencial antimicrobiano, antineoplásico e imunomodulador. Após coleta, herborização e obtenção do extrato aquoso (PBA) e acetona: água 7: 3 (orgânico) (PBO) de P. barbatus, a caracterização fitoquímica foi realizada por cromatografia líquida de alta eficiência (CLAE). A atividade antimicrobiana foi realizada para determinar a concentração inibitória mínima (CIM) contra oito cepas bacterianas usando o teste de microdiluição e o fungo Trichophyton rubrum por ensaio de difusão em disco e teste de microdiluição. A citotoxicidade foi avaliada por métodos MTT e azul de tripan em células normais mononucleares do sangue periférico (CMSP) em concentrações variadas entre 0,1 a 100 µg.mL-¹ e nas linhagens celulares neoplásicas Toledo, K562, DU-145 e PANC-¹ em 1, 10 e 100 µg.mL-¹ . A atividade imunomoduladora foi avaliada por ELISA sanduíche de citocinas pró-inflamatórias em sobrenadante de culturas de esplenócitos de camundongos BALB/c. Ambos os extratos apresentaram flavonoides, derivados cinâmicos, esteróides e ácido elágico. O PBO mostrou atividade bacteriostática contra Acinetobacter baumannii (CIM = 250 µg.mL-¹) e atividade fungistática do PBA contra Trichophyton rubrum (CIM = 800 µg.mL-¹). Os extratos não apresentaram toxicidade para CMSP e células neoplásicas (IC50 > 100 µg.mL-¹). Além disso, o PBO a 100 µg.mL-¹ inibiu significativamente as citocinas IFN-γ e IL-17A (p = 0,03). Plectranthus barbatus é um candidato potencial para uso terapêutico devido à sua baixa toxicidade em células humanas saudáveis e exibe atividade de interesse médico como bacteriostática, fungistática e imunomoduladora.(AU)


Assuntos
Plectranthus/química , Plantas Medicinais/química , Fitoterapia
9.
Acta cir. bras ; 37(1): e370105, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1364250

Resumo

Purpose: To evaluate how the induction of liver damage by ischemia and reperfusion affects the adipose tissue of lean and obese mice. Methods: Lean and diet-induced obese mice were subjected to liver ischemia (30 min) followed by 6 h of reperfusion. The vascular stromal fraction of visceral adipose tissue was analyzed by cytometry, and gene expression was evaluated by an Array assay and by RT-qPCR. Intestinal permeability was assessed by oral administration of fluorescein isothiocyanate (FITC)-dextran and endotoxemia by serum endotoxin measurements using a limulus amebocyte lysate assay. Results: It was found that, after liver ischemia and reperfusion, there is an infiltration of neutrophils, monocytes, and lymphocytes, as well as an increase in the gene expression that encode cytokines, chemokines and their receptors in the visceral adipose tissue of lean mice. This inflammatory response was associated with the presence of endotoxemia in lean mice. However, these changes were not observed in the visceral adipose tissue of obese mice. Conclusions: Liver ischemia and reperfusion induce an acute inflammatory response in adipose tissue of lean mice characterized by an intense chemokine induction and leukocyte infiltration; however, inflammatory alterations are already present at baseline in the obese adipose tissue and liver ischemia and reperfusion do not injure further.


Assuntos
Animais , Camundongos , Traumatismo por Reperfusão/veterinária , Interleucina-6 , Endotoxinas/análise , Gordura Intra-Abdominal/fisiopatologia , Inibidores do Fator de Necrose Tumoral/análise
10.
Braz. J. Biol. ; 82: 1-8, 2022. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-33486

Resumo

Chronic obstructive pulmonary disease (COPD) was estimated to be the third cause of global mortality by 2020. Acute exacerbation COPD (AECOPD) is a sudden worsening of COPD symptoms and could be due to virus/bacterial infections and air pollution. Increased expression of inflammatory markers in patients with AECOPD is associated with viral infection. This study aimed to detect different viruses and analyze the expression of various inflammatory markers associated with AECOPD patients. Three hundred and forty-seven patients diagnosed with COPD according to GOLD criteria were included in this study. Swab samples and blood were collected for the detection of viruses by RT-PCR and expression of inflammatory markers, respectively. Of the swab samples, 113 (32.6%) of samples were positive for virus detection. Of these, HRV (39.8%) was the predominant virus detected followed by FluB (27.4%) and FluA (22.1%). The presence of HRV was significantly higher (p=0.044) among the other detected viruses. When compared to healthy controls the expression levels of TNF-α, IL-6 and IL-8 were significantly higher (p<0.05) in virus-positive patients. The IL-6 and IL-8 were the next predominantly expressed in markers among the samples. The higher expression rate of IL-8 was significantly (p<0.05) associated with patients having COPD GOLD III severity level and smoking history. Although HRV was the predominant virus detected the combined prevalence of Influenza A and B surpassing the rate of HRV. The high-level expression of well known inflammatory markers of AECOPD, TNF-α, IL-6 and IL-8 indicates a chronic severe illness. These markers play an important role and could be used as a marker for determining the severity of AECOPD.(AU)


Estima-se que a doença pulmonar obstrutiva crônica (DPOC) seja a terceira causa de mortalidade global em 2020. A exacerbação aguda DPOC (AECOPD) é um agravamento súbito dos sintomas da DPOC e pode ser devido a infecções por vírus/bactérias e poluição do ar. O aumento da expressão de marcadores inflamatórios em pacientes com AECOPD está associado à infecção viral. Este estudo teve como objetivo detectar diferentes vírus e analisar a expressão de vários marcadores inflamatórios associados a pacientes com AECOPD. Trezentos e quarenta e sete pacientes com diagnóstico de DPOC de acordo com os critérios GOLD foram incluídos neste estudo. Amostras de swab e sangue foram coletadas para detecção de vírus por RT-PCR e expressão de marcadores inflamatórios, respectivamente. Das amostras de esfregaço, 113 (32,6%) amostras foram positivas para detecção de vírus. Nestas, o HRV (39,8%) foi o vírus predominante detectado, seguido do FluB (27,4%) e do FluA (22,1%). A presença de VFC foi significativamente maior (p = 0,044) entre os demais vírus detectados. Quando comparados a controles saudáveis, os níveis de expressão de TNF-α, IL-6 e IL-8 foram significativamente maiores (p <0,05) em pacientes com vírus positivo. A IL-6 e a IL-8 foram as próximas predominantemente expressas em marcadores entre as amostras. A maior taxa de expressão de IL-8 foi significativamente (p <0,05) associada a pacientes com grau de gravidade GOLD III da DPOC e história de tabagismo. Embora o HRV tenha sido o vírus predominante, a prevalência combinada de Influenza A e B ultrapassou a taxa de HRV. O alto nível de expressão de marcadores inflamatórios bem conhecidos de AECOPD, TNF-α, IL-6 e IL-8 indica uma doença crônica grave. Esses marcadores desempenham um papel importante e podem ser usados como um marcador para determinar a gravidade da AECOPD.(AU)


Assuntos
Humanos , Doença Pulmonar Obstrutiva Crônica/microbiologia , Doença Pulmonar Obstrutiva Crônica/virologia , Fator de Necrose Tumoral alfa/análise , Interleucina-6/análise , Interleucina-8/análise
11.
Braz. j. biol ; 82: e236297, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1153472

Resumo

Plectranthus barbatus Andrews (Lamiaceae) is widely distributed in the world and has a range of popular therapeutic indications. This work aimed to evaluate the phytochemical characterization of two leaf extracts of P. barbatus, and their antimicrobial, antineoplastic and immunomodulatory potential. After collection, herborization and obtainment of the P. barbatus aqueous extract (PBA) and acetone:water 7:3 P. barbatus organic extract (PBO), the phytochemical characterization was performed by high-performance liquid chromatography (HPLC). The antimicrobial activity was performed to determine the minimum inhibitory concentration (MIC) against eight bacterial strains using the microdilution test and the fungus Trichophyton rubrum by disc diffusion assay and microdilution test. Cytotoxicity was assessed by MTT and trypan blue methods in normal peripheral blood mononuclear cells (PBMCs) at concentrations ranged between 0.1 to 100 µg.mL-1 and in neoplastic cell lines Toledo, K562, DU-145 and PANC-1 at 1, 10 and 100 µg.mL-1 . Immunomodulatory activity, was evaluated by sandwich ELISA of proinflammatory cytokines at BALB/c mice splenocytes cultures supernatant. Both extracts presented flavonoids, cinnamic derivatives, steroids and ellagic acid. PBO showed bacteriostatic activity against Acinetobacter baumannii (MIC = 250 µg.mL-1) clinical isolate and PBA fungistatic activity against Trichophyton rubrum (MIC = 800 µg.mL-1). The extracts did not exhibit toxicity to PBMCs and neoplastic cells (IC50 > 100 µg.mL-1). Additionally, PBO at 100 µg.mL-1 significantly inhibited IFN-γ and IL-17A cytokines (p = 0.03). Plectranthus barbatus is a potential candidate for therapeutic use due to its low toxicity in healthy human cells and exhibits biological activities of medical interest as bacteriostatic, fungistatic and immunomodulatory.


Plectranthus barbatus Andrews (Lamiaceae) é amplamente distribuída no mundo e com uma série de indicações terapêuticas populares. Este trabalho teve como objetivo avaliar a caracterização fitoquímica de dois extratos da folha de P. barbatus e seu potencial antimicrobiano, antineoplásico e imunomodulador. Após coleta, herborização e obtenção do extrato aquoso (PBA) e acetona: água 7: 3 (orgânico) (PBO) de P. barbatus, a caracterização fitoquímica foi realizada por cromatografia líquida de alta eficiência (CLAE). A atividade antimicrobiana foi realizada para determinar a concentração inibitória mínima (CIM) contra oito cepas bacterianas usando o teste de microdiluição e o fungo Trichophyton rubrum por ensaio de difusão em disco e teste de microdiluição. A citotoxicidade foi avaliada por métodos MTT e azul de tripan em células normais mononucleares do sangue periférico (CMSP) em concentrações variadas entre 0,1 a 100 µg.mL-1 e nas linhagens celulares neoplásicas Toledo, K562, DU-145 e PANC-1 em 1, 10 e 100 µg.mL-1 . A atividade imunomoduladora foi avaliada por ELISA sanduíche de citocinas pró-inflamatórias em sobrenadante de culturas de esplenócitos de camundongos BALB/c. Ambos os extratos apresentaram flavonoides, derivados cinâmicos, esteróides e ácido elágico. O PBO mostrou atividade bacteriostática contra Acinetobacter baumannii (CIM = 250 µg.mL-1) e atividade fungistática do PBA contra Trichophyton rubrum (CIM = 800 µg.mL-1). Os extratos não apresentaram toxicidade para CMSP e células neoplásicas (IC50 > 100 µg.mL-1). Além disso, o PBO a 100 µg.mL-1 inibiu significativamente as citocinas IFN-γ e IL-17A (p = 0,03). Plectranthus barbatus é um candidato potencial para uso terapêutico devido à sua baixa toxicidade em células humanas saudáveis e exibe atividade de interesse médico como bacteriostática, fungistática e imunomoduladora.


Assuntos
Animais , Coelhos , Plectranthus , Leucócitos Mononucleares , Extratos Vegetais/farmacologia , Testes de Sensibilidade Microbiana , Arthrodermataceae , Compostos Fitoquímicos/farmacologia , Camundongos Endogâmicos BALB C
12.
J. venom. anim. toxins incl. trop. dis ; 28: e20210124, 2022. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1386128

Resumo

Triatomines are blood-feeding arthropods belonging to the subfamily Triatominae (Hemiptera; Reduviidae), capable of producing immunomodulatory and water-soluble molecules in their hemolymph, such as antimicrobial peptides (AMPs). In this work, we evaluated the antifungal and immunomodulatory activity of the hemolymph of Meccus pallidipennis (MPH) and Rhodnius prolixus (RPH) against Cryptococcus neoformans. Methods: We assessed the activity of the hemolymph of both insects on fungal growth by a minimum inhibitory concentration (MIC) assay. Further, RAW 264.7 macrophages were cultivated with hemolymph and challenged with C. neoformans. Then, their phagocytic and killing activities were assessed. The cytokines MCP-1, IFN-γ, TNF-α, IL-10, IL-12, and IL-6 were measured in culture supernatants 4- and 48-hours post-infection. Results: Both hemolymph samples directly affected the growth rate of the fungus in a dose-dependent manner. Either MPH or RPH was capable of inhibiting fungal growth by at least 70%, using the lowest dilution (1:20). Treatment of RAW 264.7 macrophages with hemolymph of both insects was capable of increasing the production of MCP-I and TNF-α. In addition, when these cells were stimulated with hemolymph in the presence of C. neoformans, a 2- and a 4-fold increase in phagocytic rate was observed with MPH and RPH, respectively, when compared to untreated cells. For the macrophage killing activity, MPH decreased in approximately 30% the number of viable yeasts inside the cells compared to untreated control; however, treatment with RPH could not reduce the total number of viable yeasts. MPH was also capable of increasing MHC-II expression on macrophages. Regarding the cytokine production, MCP-I and TNF-α, were increased in the supernatant of macrophages treated with both hemolymphs, 4 and 48 hours after stimulation. Conclusion: These results suggested that hemolymph of triatomines may represent a source of molecules capable of presenting antifungal and immunomodulatory activity in macrophages during fungal infection.(AU)


Assuntos
Animais , Hemolinfa/química , Triatominae/microbiologia , Criptococose/terapia , Cryptococcus neoformans/imunologia , Antifúngicos/uso terapêutico , Imunomodulação/fisiologia
13.
Acta cir. bras ; 37(12): e371204, 2022. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1415500

Resumo

Purpose: To evaluate effect of N-acetylcysteine (NAC) associated with Ringer lactate or hypertonic saline in inflammation and bacterial translocation on experimental intestinal obstruction (IO). Methods: Wistar rats was subjected to IO. Six or 24 hours after, rats were subjected to enterectomy and fluid resuscitation: IO, RL (subjected to the same procedures but with fluid resuscitation using Ringer's lactate solution); RLNAC (added NAC to Ringer's solution); and HSNAC (surgical procedure + fluid reposition with 7.5% hypertonic saline and NAC). After 24 h, tissues were collected to cytokines, bacterial translocation, and histological assessments. Results: In kidney, interleukin-1beta (IL-1beta) was lower in the groups with fluid resuscitation compared to IO group. The RLNAC showed lower levels compared to the RL. Interleukin-6 (IL-6), interleukin-10 (IL-10), tumor necrosis factor-alpha (TNF-alpha), and (IFN-gamma) were lower in the treatment groups than in IO. In lung, IL-1beta and IL-6 were lower in RLNAC compared to IO. IL-10 was lower in RL, RLNAC and HSNAC compared to IO. TNF-alpha was higher in HSNAC compared to both RL and RLNAC. Bacterial translocation was observed in all animals of IO group. In kidneys, inflammation and congestion degrees were lower in HSNAC compared to RL. In lungs, inflammation levels were higher in RLNAC compared with the sham group. Conclusions: The data indicates that NAC associated with RL can promote a decrease in the inflammatory process in the kidneys and lungs in rats, following intestinal obstruction and ischemia in rats.


Assuntos
Animais , Ratos , Acetilcisteína/administração & dosagem , Acetilcisteína/uso terapêutico , Translocação Bacteriana/efeitos dos fármacos , Inflamação/tratamento farmacológico , Obstrução Intestinal , Isquemia , Animais de Laboratório
14.
Anim. Reprod. (Online) ; 18(1): e20200048, 2021. graf
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1285122

Resumo

Abstract This review focuses on the innate immune events modulated by conceptus signaling during early pregnancy in ruminants. Interferon-tau (IFN-τ) plays a role in the recognition of pregnancy in ruminants, which involves more than the inhibition of luteolytic pulses of PGF2α to maintain corpus luteum function. For successful pregnancy establishment, the allogenic conceptus needs to prevent rejection by the female. Therefore, IFN-τ exerts paracrine and endocrine actions to regulate the innate immune system and prevent conceptus rejection. Additionally, other immune regulators work in parallel with IFN-τ, such as the pattern recognition receptors (PRR). These receptors are activated during viral and bacterial infections and in early pregnancy, but it remains unknown whether PPR expression and function are controlled by IFN-τ. Therefore, this review focuses on the main components of the innate immune response that are involved with early pregnancy and their importance to avoid conceptus rejection.

15.
Anim. Reprod. ; 18(1): e20200048, fev. 2021. ilus
Artigo em Inglês | VETINDEX | ID: vti-31083

Resumo

This review focuses on the innate immune events modulated by conceptus signaling during early pregnancy in ruminants. Interferon-tau (IFN-) plays a role in the recognition of pregnancy in ruminants, which involves more than the inhibition of luteolytic pulses of PGF2 to maintain corpus luteum function. For successful pregnancy establishment, the allogenic conceptus needs to prevent rejection by the female. Therefore, IFN- exerts paracrine and endocrine actions to regulate the innate immune system and prevent conceptus rejection. Additionally, other immune regulators work in parallel with IFN-, such as the pattern recognition receptors (PRR). These receptors are activated during viral and bacterial infections and in early pregnancy, but it remains unknown whether PPR expression and function are controlled by IFN-. Therefore, this review focuses on the main components of the innate immune response that are involved with early pregnancy and their importance to avoid conceptus rejection.(AU)


Assuntos
Animais , Feminino , Gravidez , Ruminantes/embriologia , Ruminantes/imunologia , Prenhez , Luteólise , Sistema Imunitário , Interleucinas , Dinoprosta
16.
Semina ciênc. agrar ; 42(6): 3289-3304, nov.-dez. 2021. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1370494

Resumo

In the present study, we describe the proliferative response and the IFN-γ, IL-10, IL-4 cytokine expression profiles in peripheral blood, and IgG production, after the experimental infection of Santa Inês sheep with 250 Fasciola hepatica metacercariae that were evaluated at 60 and 210 days post-infection(dpi). The cytokine expression profile at 60 dpi was characterized by the production of IFN-γ and IL-10, which is indicative of an initial mixed Th1/Th2 response. The modulation of the response occurred at 210 dpi with a predominance of IL-10 and IL-4 over IFN-γ. Mononuclear cells from peripheral blood stimulated with F. hepatica antigen exhibited proliferative capacity at 60 dpi, whereas the response was consistent with modulation from Th1 to Th2 in the chronic phase. The IgG antibody response was more marked at 60 days than at 210 dpi, confirming the mixed-response profile. The late modulation of the T lymphocyte response in association with the predominance of IL-10 and IL-4 at 210 dpi suggests the involvement of these cytokines after the establishment of the parasites in the bile ducts. The transition from a mixed to a regulatory response in the chronic phase was also accompanied by a reduced number of eggs per gram of feces.(AU)


No presente estudo, observou-se a resposta proliferativa e os perfis de expressão de citocinas IFN-γ, IL10, IL-4 no sangue periférico, e a produção de IgG, aos 60 e 210 dias após infecção (dpi) experimental de ovinos Santa Inês com 250 metacercárias de Fasciola hepatica. O perfil de expressão de citocinas aos 60 dpi foi caracterizado pela produção de IFN-γ e IL-10, o que é indicativo de uma resposta mista inicial Th1/ Th2. A modulação da resposta ocorreu aos 210 dpi, com predominância de IL-10 e IL-4 sobre IFN-γ. As células mononucleares do sangue periférico estimuladas com antígeno total de F. hepatica adulta exibiram capacidade proliferativa aos 60 dpi, enquanto a resposta foi consistente com uma modulação de Th1 para Th2 na fase crônica. A resposta do anticorpo IgG foi maior aos 60 dpi do que aos 210 dpi. A modulação tardia da resposta dos linfócitos T em associação com a predominância de IL-10 e IL-4 aos 210 dpi sugere o envolvimento dessas citocinas após o estabelecimento dos parasitos nos ductos biliares. A transição de uma resposta mista para uma resposta com pefil regulador na fase crônica também foi acompanhada por redução dos ovos por grama de fezes.(AU)


Assuntos
Animais , Ovinos , Fasciolíase , Imunidade , Fasciola hepatica
17.
Semina ciênc. agrar ; 42(6): 3321-3336, nov.-dez. 2021. tab, graf, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1370531

Resumo

The combination of medroxyprogesterone acetate (MPA) and gonadotropin chorionic (eCG) has been widely used to synchronize oestrus cycle in sheep, but their effects on the gene expression in uterine tissue are yet to be elucidated. To evaluate the effect of MPA + eCG or prostaglandin analogue (PA) treatments on the rate of oestrus cycle synchronization, as well as further hormone production and gene expression profiles in uterine tissue, 14 Santa Inês ewes were randomly selected. The MPA + eCG group (n=7) received intravaginal insertion of MPA-impregnated sponges for 14 days and was administered 350 IU eCG on the day of sponge withdrawal. The PA group (n=7) was administered two doses of 100 µg of PA separated by 12 days. The ewes were assessed for the rate of oestrus cycle synchronization and the serum concentrations of progesterone (P4) and estradiol (E2). Additionally, the expression of estrogen receptor (ERα), progesterone receptor (P4R), and immunolocalization of interferon receptor (IFNAR1) in the uterine tissue samples collected 15th day post-mating were examined. The rate of oestrus cycle synchronization was 100% (n=7/7) and 57.14% (n=4/7) in the MPA + eCG and PA groups, respectively. Moreover, the MPA + eCG group exhibited higher serum concentration of P4 than the PA group (p < 0.05). However, the E2 serum concentration did not differ between the two groups (p > 0.05). The relative expression of P4R and ERα mRNA analyzed using real-time PCR and immunodetection of IFNAR1 were similar between the two groups tested (p > 0.05). Conclusively, MPA + eCG treatment improved the rate of oestrus cycle synchronization and endogenous P4 production; however, it did not affect the expression of sex steroid receptors and IFNAR1 in uterine ovine tissue.(AU)


A combinação de acetato de medroxiprogesterona (MPA) com gonadotrofina coriônica (eCG) é amplamente utilizada para sincronizar o estro de ovelhas, mas seus possíveis efeitos sobre a expressão gênica em tecido uterino não foram elucidados. Para avaliar o efeito dos protocolos MPA + eCG ou análogo de prostaglandina (PA) sobre a taxa de sincronização do estro, bem como na futura produção hormonal e expressão gênica em tecido uterino, 14 ovelhas Santa Inês foram selecionadas. O grupo MPA + eCG (n=7) recebeu a inserção de esponjas impregnadas de MPA por via intravaginal por 14 dias e 350 UI de eCG no dia da retirada da esponja. O grupo PA recebeu duas doses de 100 µg de PA administradas com 12 dias de intervalo. As ovelhas foram avaliadas quanto à taxa de sincronização do estro, concentração sérica de progesterona (P4) e estradiol (E2). Além disso, foram examinadas a expressão do receptor de estradiol (ERα), receptor de progesterona (P4R) e localização do receptor de interferon (IFNAR1), a partir de amostras de tecido uterino coletadas 15 dias após o acasalamento. A taxa de sincronização do estro foi 100% (n = 7/7) e 57,14% (n = 4/7) nos grupos MPA + eCG e PA, respectivamente. Além disso, o grupo MPA + eCG apresentou maior concentração sérica de P4 em comparação com o grupo PA (P < 0,05). No entanto, a concentração sérica de E2 não diferiu entre os grupos testados (P > 0,05). A expressão relativa de RNAm para P4R e ERα analisado por PCR em tempo real e imunodetecção de IFNAR1 foi semelhante entre os grupos testados (P > 0,05). Em conclusão, o tratamento com MPA + eCG melhora a taxa de sincronização do estro e a produção de progesterona endógena; contudo, não afeta a regulação da expressão de receptores de esteroides sexuais e IFNAR1 no tecido uterino de ovinos.(AU)


Assuntos
Animais , Feminino , Útero , Ovinos , Receptores de Progesterona , Expressão Gênica , Ciclo Estral , Receptor de Interferon alfa e beta
18.
J. venom. anim. toxins incl. trop. dis ; 27: e20200149, 2021. graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1154771

Resumo

Skin lesions of patients affected by non-ulcerated cutaneous leishmaniasis (NUCL) caused by L. (L.) infantum chagasi are characterized by lymphohistiocytic inflammatory infiltrate associated with epithelioid granuloma and scarce parasitism. However, the in situ cellular immune response of these patients is unclear. Therefore, the aim of the present study was to characterize the cellular immune response in the skin lesions of patients affected by NUCL. Methods Twenty biopsies were processed by immunohistochemistry using primary antibodies to T lymphocytes (CD4, CD8), NK cells, B lymphocytes, macrophages, nitric oxide synthase and interferon-gamma. Results Immunohistochemistry revealed higher expression of all cellular types and molecules (IFN-γ, iNOS) in the dermis of diseased skin compared to the skin of healthy individuals (p < 0.05). Morphometric analysis performed in the skin lesions sections showed the predominance of CD8+ T lymphocytes in the mononuclear infiltrate, followed by macrophages, mostly iNOS+, a response that could be mediated by IFN-γ. Conclusion Our study improves knowledge of the cellular immune response in non-ulcerated or atypical cutaneous leishmaniasis caused by L. (L.) infantum chagasi in Central America and pointed to the pivotal participation of CD8+ T lymphocytes in the host defense mechanisms against the parasite in patients with NUCL.(AU)


Assuntos
Imuno-Histoquímica , Derme/lesões , Imunidade , Leishmania , Infecções
19.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 27: e20200149, 2021. graf, ilus
Artigo em Inglês | VETINDEX | ID: vti-31984

Resumo

Skin lesions of patients affected by non-ulcerated cutaneous leishmaniasis (NUCL) caused by L. (L.) infantum chagasi are characterized by lymphohistiocytic inflammatory infiltrate associated with epithelioid granuloma and scarce parasitism. However, the in situ cellular immune response of these patients is unclear. Therefore, the aim of the present study was to characterize the cellular immune response in the skin lesions of patients affected by NUCL. Methods Twenty biopsies were processed by immunohistochemistry using primary antibodies to T lymphocytes (CD4, CD8), NK cells, B lymphocytes, macrophages, nitric oxide synthase and interferon-gamma. Results Immunohistochemistry revealed higher expression of all cellular types and molecules (IFN-γ, iNOS) in the dermis of diseased skin compared to the skin of healthy individuals (p < 0.05). Morphometric analysis performed in the skin lesions sections showed the predominance of CD8+ T lymphocytes in the mononuclear infiltrate, followed by macrophages, mostly iNOS+, a response that could be mediated by IFN-γ. Conclusion Our study improves knowledge of the cellular immune response in non-ulcerated or atypical cutaneous leishmaniasis caused by L. (L.) infantum chagasi in Central America and pointed to the pivotal participation of CD8+ T lymphocytes in the host defense mechanisms against the parasite in patients with NUCL.(AU)


Assuntos
Imuno-Histoquímica , Derme/lesões , Imunidade , Leishmania , Infecções
20.
Acta amaz. ; 51(3): 199-206, 2021. mapas, tab, ilus, graf
Artigo em Inglês | VETINDEX | ID: vti-764738

Resumo

While the Brazilian National Forest Inventory (NFI) is in progress, there is a growing demand to understand the effect of cluster size on the accuracy and precision of forest-attribute estimation. We aimed to find the minimum cluster size (in area) to estimate merchantable volume (MV) with the same accuracy and precision as the estimates derived from the original cluster of 8,000 m2. We used data from an inventory carried out in a forest unit (Bom Futuro National Forest) in the southwestern Brazilian Amazon, where 22 clusters were distributed as a two-stage sampling design. Three products were evaluated: (i) MV of trees with a diameter at breast height (DBH) ≥ 20 cm (P1); (ii) MV of trees with DBH ≥ 50 cm (P2); and (iii) MV of commercial species with DBH ≥ 50 cm and stem quality ‘level 1 or ‘level 2 (P3). We assessed ten scenarios in which the cluster size was reduced from 8,000 m2 to 800 m2. The accuracy of P1, P2 and P3 was highly significantly lower for reductions < 2,400 m². The precision was more sensitive to variations in cluster size, especially for P2 and P3. Minimum cluster sizes were ≥ 2,400 m² to estimate P1, ≥ 4,800 m² to estimate P2, and ≥ 7,200 m² to estimate P3. We concluded that it is possible to reduce the cluster size without losing the accuracy and precision given by the original NFI cluster. A cluster of 2,400 m² provides estimates as accurate as the original cluster, regardless of the evaluated product.(AU)


Enquanto o Inventário Florestal Nacional Brasileiro (IFN) está em andamento, há uma demanda crescente para entender o efeito da área do conglomerado sobre a exatidão e precisão da estimativa de atributos florestais. O objetivo deste estudo foi determinar a área mínima de um conglomerado para estimar o volume comercial (VC) com a mesma acurácia e precisão que as estimativas derivadas do conglomerado original de 8.000 m². A base de dados é proveniente de um inventário realizado em uma unidade florestal (Floresta Nacional do Bom Futuro) no sudoeste da Amazônia brasileira, onde 22 conglomerados foram distribuídos em um desenho amostral em dois estágios. Foram avaliados três produtos: (i) VC de árvores com diâmetro à altura do peito (DAP) ≥ 20 cm (P1); (ii) VC de árvores com DAP ≥ 50 cm (P2); e (iii) VC de espécies comerciais com DAP ≥ 50 cm e qualidade de fuste ‘nível 1 ou ‘nível 2 (P3). O estudo avaliou dez cenários em que a área do conglomerado foi reduzida de 8.000 a 800 m². A acurácia de P1, P2 e P3 foi significativamente menor para reduções < 2.400 m². A precisão foi mais sensível à variação no tamanho do conglomerado, sobretudo para P2 e P3. Os tamanhos mínimos de conglomerado foram ≥ 2.400 m² para estimar P1, ≥ 4.800 m² para estimar P2 e ≥ 7.200 m² para estimar P3. Concluímos que é possível reduzir a área do conglomerado sem perder acurácia e precisão do conglomerado original do IFN. Um conglomerado de 2.400 m² fornece estimativas com a mesma acurácia que o conglomerado original, independentemente do produto avaliado.(AU)


Assuntos
Árvores/crescimento & desenvolvimento , Titulometria , Ecossistema Amazônico/análise
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