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1.
Head Neck Pathol ; 18(1): 42, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38735890

RESUMO

PURPOSE: This study aimed to characterize the histopathological immunohistochemical features of chronic sclerosing sialadenitis, emphasizing the IgG4-related disease. METHODS: Seventeen cases of chronic sclerosing sialoadenitis were examined for histopathological aspects, (inflammation, fibrosis, glandular parenchyma, and lymphoid follicles) and immunohistochemistry (BCL2, CD3, CD20, CD34, CD163, p63, cyclin D1, mast cell, SMA, S100A4, IgG, and IgG4) which were scored. IgG4-related disease features were investigated. Demographic and clinical data were also collected. RESULTS: Males predominated (10:7), with an average lesion size of 3.9 cm. Common histopathological findings included reduced acinar parenchyma, lymphoid follicle formation, and ductular proliferation. CD3-positive T lymphocytes and CD34- and SMA-positive stromal fibroblasts were abundant. Nine cases (53%) showed sialoliths and three cases met the criteria for IgG4-related disease. CONCLUSION: CSS of the submandibular gland represents a reactive pattern rather than IgG4-RD as only 3 cases seemed to be related to IgG4-RD. The immunohistochemical profile revealed an abundant population of CD3-positive T lymphocytes, as opposed to regulatory proteins such as cyclin D1, demonstrating that populations of CD34- and SMA-positive stromal fibroblasts contribute to the fibrosis characteristic of CSS. In addition, our results provide a comprehensive insight into the study of CSS and its relationship with IgG4-RD.


Assuntos
Doença Relacionada a Imunoglobulina G4 , Sialadenite , Humanos , Masculino , Sialadenite/patologia , Feminino , Pessoa de Meia-Idade , Adulto , Doença Relacionada a Imunoglobulina G4/patologia , Idoso , Esclerose/patologia , Doença Crônica , Glândula Submandibular/patologia , Imuno-Histoquímica
2.
Int J Mol Sci ; 25(9)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38732154

RESUMO

The diagnosis of cardiovascular disease (CVD) is still limited. Therefore, this study demonstrates the presence of human ether-a-go-go-related gene 1 (hERG1) and heat shock protein 47 (Hsp47) on the surface of small extracellular vesicles (sEVs) in human peripheral blood and their association with CVD. In this research, 20 individuals with heart failure and 26 participants subjected to cardiac stress tests were enrolled. The associations between hERG1 and/or Hsp47 in sEVs and CVD were established using Western blot, flow cytometry, electron microscopy, ELISA, and nanoparticle tracking analysis. The results show that hERG1 and Hsp47 were present in sEV membranes, extravesicularly exposing the sequences 430AFLLKETEEGPPATE445 for hERG1 and 169ALQSINEWAAQTT- DGKLPEVTKDVERTD196 for Hsp47. In addition, upon exposure to hypoxia, rat primary cardiomyocytes released sEVs into the media, and human cardiomyocytes in culture also released sEVs containing hERG1 (EV-hERG1) and/or Hsp47 (EV-Hsp47). Moreover, the levels of sEVs increased in the blood when cardiac ischemia was induced during the stress test, as well as the concentrations of EV-hERG1 and EV-Hsp47. Additionally, the plasma levels of EV-hERG1 and EV-Hsp47 decreased in patients with decompensated heart failure (DHF). Our data provide the first evidence that hERG1 and Hsp47 are present in the membranes of sEVs derived from the human cardiomyocyte cell line, and also in those isolated from human peripheral blood. Total sEVs, EV-hERG1, and EV-Hsp47 may be explored as biomarkers for heart diseases such as heart failure and cardiac ischemia.


Assuntos
Biomarcadores , Doenças Cardiovasculares , Vesículas Extracelulares , Proteínas de Choque Térmico HSP47 , Miócitos Cardíacos , Humanos , Vesículas Extracelulares/metabolismo , Biomarcadores/sangue , Masculino , Doenças Cardiovasculares/metabolismo , Feminino , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Pessoa de Meia-Idade , Animais , Proteínas de Choque Térmico HSP47/metabolismo , Ratos , Canal de Potássio ERG1/metabolismo , Idoso , Adulto , Canais de Potássio Éter-A-Go-Go/metabolismo , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/sangue
3.
Oral Dis ; 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693620

RESUMO

Targeted therapy has the potential to be used in the neoadjuvant setting for odontogenic tumors, reducing the morbidities associated with major surgery. In this regard, the aim of this study was to summarize the current evidence on the different forms of targeted therapy, effectiveness, and drawbacks of this course of treatment. Four databases were searched electronically without regard to publication date or language. Grey literature searches and manual searches were also undertaken. Publications with sufficient clinical data on targeted therapy for odontogenic tumors were required to meet the criteria for eligibility. The analysis of the data was descriptive. A total of 15 papers comprising 17 cases (15 ameloblastomas and 2 ameloblastic carcinomas) were included. Numerous mutations were found, with BRAF V600E being most common. Dabrafenib was the most utilized drug in targeted therapy. Except for one case, the treatment reduced the size of the lesion (16/17 cases), showing promise. Most of the adverse events recorded were mild, such as skin issues, voice changes, abnormal hair texture, dry eyes, and systemic symptoms (e.g., fatigue, joint pain, and nausea). It is possible to reach the conclusion that targeted therapy for ameloblastoma and ameloblastic carcinoma may be a useful treatment strategy, based on the findings of the included studies.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38760286

RESUMO

Tenosynovial giant cell tumor is a benign neoplasm arising from the synovium of joints, including the temporomandibular joint (TMJ). Despite its benign nature, these tumors may exhibit aggressive behavior. A 57-year-old woman with a swollen, hardened area in the left TMJ was referred to the university´s clinic. The diagnosis of tenosynovial giant cell tumor was made based on the presence of hyperplastic synovial lining containing mononuclear and giant cells, hemorrhagic areas, hemosiderin deposits, and calcification foci in the biopsy. A low condylectomy was performed, and histopathologic analysis of the surgical piece upheld the diagnosis. Due to histopathologic resemblance with other giant cell-rich lesions (giant cell granuloma of the jaws, brown tumor of hyperparathyroidism, and non-ossifying fibroma) for which signature mutations are known, mutational analysis of KRAS, FGFR1, and TRPV4 genes was conducted. The results revealed wild-type sequences for all the mutations tested, thereby supporting the diagnosis of tenosynovial giant cell tumor.

5.
Int J STD AIDS ; : 9564624241246298, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38606785

RESUMO

BACKGROUND: This study evaluated the presence of Epstein-Barr virus type 1 (EBV-1) DNA in patients living with HIV, before and after three different topical therapy protocols for oral hairy leukoplakia (OHL). METHODS: The sample consisted of five patients treated with topical solution of 25% podophyllin resin; six with 25% podophyllin resin plus 5% acyclovir cream; and four with 25% podophyllin resin plus 1% penciclovir cream. DNA was extracted from OHL scrapings and amplified by the PCR using specific primers for EBV-1 (EBNA-1). RESULTS: Clinical healing of OHL lesions was observed across all treatment groups over time. At baseline, EBNA-1 was detected in all OHL lesions. After treatment, OHL samples from three patients treated with 25% podophyllin resin plus 5% acyclovir cream and from one patient treated with 25% podophyllin resin plus 1% penciclovir cream exhibited negative EBNA-1 viral gene encoding. Despite the clinical resolution of OHL, 11 patients (73.3%) showed EBNA-1 positivity immediately after the lesion disappeared. Three patients (20%) treated with podophyllin resin displayed both EBNA-1 positivity and a recurrence of OHL, in contrast to no recurrence in the other two groups. CONCLUSIONS: These findings suggest potential associations between treatment formulations, EBNA-1 persistence, and the recurrence of OHL lesions.

6.
NPJ Parkinsons Dis ; 10(1): 82, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609392

RESUMO

Understanding medium spiny neuron (MSN) physiology is essential to understand motor impairments in Parkinson's disease (PD) given the architecture of the basal ganglia. Here, we developed a custom three-chambered microfluidic platform and established a cortico-striato-nigral microcircuit partially recapitulating the striatal presynaptic landscape in vitro using induced pluripotent stem cell (iPSC)-derived neurons. We found that, cortical glutamatergic projections facilitated MSN synaptic activity, and dopaminergic transmission enhanced maturation of MSNs in vitro. Replacement of wild-type iPSC-derived dopamine neurons (iPSC-DaNs) in the striatal microcircuit with those carrying the PD-related GBA-N370S mutation led to a depolarisation of resting membrane potential and an increase in rheobase in iPSC-MSNs, as well as a reduction in both voltage-gated sodium and potassium currents. Such deficits were resolved in late microcircuit cultures, and could be reversed in younger cultures with antagonism of protein kinase A activity in iPSC-MSNs. Taken together, our results highlight the unique utility of modelling striatal neurons in a modular physiological circuit to reveal mechanistic insights into GBA1 mutations in PD.

8.
J Neurointerv Surg ; 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443187

RESUMO

OBJECTIVE: To evaluate clinical, angiographic features, and endovascular approach of ruptured and unruptured distal intracranial aneurysms (DIAs). METHODS: From January 2013 to February 2022, details of all consecutive intracranial aneurysms (IAs) treated endovascularly in our center were collected and retrospectively reviewed. IAs involving the anterior cerebral artery, middle cerebral artery, and posterior cerebral artery (distal to anterior communicating artery, limen insula, and P1 segment, respectively), and those distal to superior cerebellar artery, anterior-inferior cerebellar artery, and posterior inferior cerebellar artery's first segment were classified based on their etiology, location, size, and shape. Demographic, clinical, angiographic, and procedural variables, as well as follow-up outcomes were evaluated. RESULTS: Of 2542 IAs, 151 (5.9%) DIAs were counted (average size 5.4±2.9 mm), including 61 (40.4%) unruptured and 90 (59.6%) ruptured. No difference in the aneurysmal size was observed, but aneurysms smaller than 4 mm were observed more frequently in the ruptured group (36.7% vs 18%; P=0.01). In addition, ruptured DIAs were more often non-saccular (40% vs 18%; P=0.004) and irregular (93.3% vs 59%; P<0.001), They were treated mostly by coiling, glue, and parent artery sacrifice (P=0.02, P=0.006, and P=0.001), whereas unruptured DIAs were treated by stent-assisted coiling and flow-diverter stents (P=0.001 and P<0.001, respectively), without any differences in occlusion (81.6% vs 82.5%) and recanalization (21.1% vs 17.5%) rates. Procedure-related complications occurred in 20/151 (13.2%) patients, without any differences between subgroups. Ruptured DIAs were more often re-treated (18.4% vs 5.3%, P=0.02). In multivariate analyses, irregular shape appeared as an independent predictor of ruptured presentation (OR=8.1, 95% CI 3.0 to 21.7; P<0.001). CONCLUSIONS: Compared with unruptured DIAs, ruptured DIAs were more often non-saccular, irregular, and smaller than 4 mm. Despite different therapeutical approaches, ruptured and unruptured DIAs presented comparable occlusion and recanalization rates.

9.
Oral Maxillofac Surg ; 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38467949

RESUMO

BACKGROUND: Pyodermatitis-pyostomatitis vegetans (PPV) is a rare mucocutaneous disease characterized by multiple pustules and it is considered a marker for inflammatory bowel disease (IBD). The oral manifestations of this condition are referred to as pyostomatitis vegetans (PSV). PURPOSE: To investigate which features could help in establishing the diagnosis of PSV, with or without cutaneous lesions, based on information retrieved from all cases of PSV described in the literature. A case of PV from the authors was also included in the analysis. METHODS: An electronic search was undertaken, last updated in August 2022. Inclusion criteria included publications reporting cases of PSV, with the diagnosis confirmed by the pathological examination of oral or skin lesions, and presence of IBD. RESULTS/CONCLUSIONS: Sixty-two publications with 77 cases of PSV and an associated IBD were included. Features that are helpful in establishing the diagnosis of PSV are snail track appearance of oral lesions, an associated IBD (which is not always symptomatic), evidence of intraepithelial clefting on microscopic examination of oral lesions, and peripheral blood eosinophilia. A gold standard for the management of PSV does not exist and high-level evidence is limited. There is no established therapeutic protocol for PSV and management primarily consists of topical and/or systemic corticosteroids, antirheumatic drugs (sulfasalazine, mesalazine), monoclonal antibody (infliximab, adalimumab) immunosuppressives (azathioprine, methotrexate), antibiotics (dapsone), or a combination of these. The risk of recurrence of oral lesions is considerable when the medication dose is decreased or fully interrupted.

11.
Hum Brain Mapp ; 45(3): e26630, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38376145

RESUMO

The frontal aslant tract (FAT) is a crucial neural pathway of language and speech, but little is known about its connectivity and segmentation differences across populations. In this study, we investigate the probabilistic coverage of the FAT in a large sample of 1065 young adults. Our primary goal was to reveal individual variability and lateralization of FAT and its structure-function correlations in language processing. The study utilized diffusion MRI data from 1065 subjects obtained from the Human Connectome Project. Automated tractography using DSI Studio software was employed to map white matter bundles, and the results were examined to study the population variation of the FAT. Additionally, anatomical dissections were performed to validate the fiber tracking results. The tract-to-region connectome, based on Human Connectome Project-MMP parcellations, was utilized to provide population probability of the tract-to-region connections. Our results showed that the left anterior FAT exhibited the most substantial individual differences, particularly in the superior and middle frontal gyrus, with greater variability in the superior than the inferior region. Furthermore, we found left lateralization in FAT, with a greater difference in coverage in the inferior and posterior portions. Additionally, our analysis revealed a significant positive correlation between the left FAT inferior coverage area and the performance on the oral reading recognition (p = .016) and picture vocabulary (p = .0026) tests. In comparison, fractional anisotropy of the right FAT exhibited marginal significance in its correlation (p = .056) with Picture Vocabulary Test. Our findings, combined with the connectivity patterns of the FAT, allowed us to segment its structure into anterior and posterior segments. We found significant variability in FAT coverage among individuals, with left lateralization observed in both macroscopic shape measures and microscopic diffusion metrics. Our findings also suggested a potential link between the size of the left FAT's inferior coverage area and language function tests. These results enhance our understanding of the FAT's role in brain connectivity and its potential implications for language and executive functions.


Assuntos
Conectoma , Substância Branca , Humanos , Adulto Jovem , Imagem de Tensor de Difusão , Encéfalo/diagnóstico por imagem , Lobo Frontal/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Idioma , Vias Neurais/diagnóstico por imagem
12.
Clin Pediatr (Phila) ; : 99228241230390, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38327253

RESUMO

INTRODUCTION: Traumatic brain injury (TBI) can disrupt the hypothalamo-pituitary axis, causing neuroendocrine dysfunction. As a third of children can develop post-traumatic hypothalamo-pituitary axis dysfunction (HPAD), a longitudinal follow-up is required in children with TBI. METHOD: The study comprised a pre-quality improvement (QI) phase (baseline phase) and a QI phase (post-intervention phase). Retrospective data were collected on children with TBI at our hospital during the pre-QI phase of the study to estimate the baseline data on HPAD prevalence and pediatric endocrine referral rate. Guidance protocol for standardizing the pediatric endocrine referral, evaluation, and follow-up of children with TBI was implemented. Prospective data were collected to estimate outcome measures (prevalence of HPAD, rate of initial endocrine consultation and outpatient follow-up) and process measures (protocol adherence rate). RESULT: Twenty-seven children, aged ≤19 years, were admitted with TBI in the pre-QI phase. The median age was 9 years. Motor vehicle accidents predominated. Thirty percent had limited endocrine evaluation, and 4% had transient cranial diabetes insipidus (DI). The QI phase included 8 children. Demographic data were similar to those in the pre-QI phase. Both outcome and process measures increased to 75% from the pre-QI phase following the protocol implementation. CONCLUSION: A lower prevalence rate of HPAD in the current cohort may be owing to underevaluation and a smaller sample size. The QI initiative incorporating a guidance protocol-based endocrinological approach to children with TBI improved the pediatric endocrinology referral and follow-up rates.

14.
Clin Case Rep ; 12(1): e8444, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38259867

RESUMO

Clinical Key Message: We present a case of recurring ameloblastoma in soft tissue, for which we have estimated the growth rate of the lesion. This information could help clinicians to establish follow-up protocols for the early diagnosis of recurrent ameloblastomas. Abstract: In the present paper, we present a case of recurring ameloblastoma in soft tissue, for which we have estimated the growth rate of the lesion. The area of the whole resected specimen was measured using the ImageJ guide for complex object area. After dividing the area of the recurrent tumor by the number of years during the follow-up, we found that the lesion growth rate was 5.3 cm2 per year. Although further studies are still necessary in the literature to assess the growth rate of ameloblastoma, the present report shows a different methodology to estimate it. This information could help clinicians to establish follow-up protocols for the early diagnosis of recurrent ameloblastomas.

15.
BMJ Open ; 14(1): e076217, 2024 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-38184316

RESUMO

OBJECTIVES: To externally validate the four-variable kidney failure risk equation (KFRE) in the Peruvian population for predicting kidney failure at 2 and 5 years. DESIGN: A retrospective cohort study. SETTING: 17 primary care centres from the Health's Social Security of Peru. PARTICIPANTS: Patients older than 18 years, diagnosed with chronic kidney disease stage 3a-3b-4 and 3b-4, between January 2013 and December 2017. Patients were followed until they developed kidney failure, died, were lost, or ended the study (31 December 2019), whichever came first. PRIMARY AND SECONDARY OUTCOME MEASURES: Performance of the KFRE model was assessed based on discrimination and calibration measures considering the competing risk of death. RESULTS: We included 7519 patients in stages 3a-4 and 2798 patients in stages 3b-4. The estimated cumulative incidence of kidney failure, accounting for competing event of death, at 2 years and 5 years, was 1.52% and 3.37% in stages 3a-4 and 3.15% and 6.86% in stages 3b-4. KFRE discrimination at 2 and 5 years was high, with time-dependent area under the curve and C-index >0.8 for all populations. Regarding calibration in-the-large, the observed to expected ratio and the calibration intercept indicated that KFRE underestimates the overall risk at 2 years and overestimates it at 5 years in all populations. CONCLUSIONS: The four-variable KFRE models have good discrimination but poor calibration in the Peruvian population. The model underestimates the risk of kidney failure in the short term and overestimates it in the long term. Further research should focus on updating or recalibrating the KFRE model to better predict kidney failure in the Peruvian context before recommending its use in clinical practice.


Assuntos
Insuficiência Renal Crônica , Insuficiência Renal , Humanos , Prognóstico , Peru/epidemiologia , Estudos Retrospectivos , Insuficiência Renal/epidemiologia , Insuficiência Renal Crônica/epidemiologia
17.
Odontology ; 112(1): 208-220, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37058199

RESUMO

PURPOSE: Periodontitis and coronavirus disease (COVID-19) share risk factors and activate similar immunopathological pathways, intensifying systemic inflammation. This study investigated the clinical, immunological and microbiological parameters in individuals with COVID-19 and controls, exploring whether periodontitis-driven inflammation contributes to worsening COVID-19 endpoints. METHODS: Case (positive RT-PCR for SARS-CoV-2) and control (negative RT-PCR) individuals underwent clinical and periodontal assessments. Salivary levels of TNF-α, IL-6, IL-1ß, IL-10, OPG, RANKL, neutrophil extracellular traps, and subgingival biofilm were analyzed at two timepoints. Data on COVID-19-related outcomes and comorbidity information were evaluated from medical records. RESULTS: Ninety-nine cases of COVID-19 and 182 controls were included for analysis. Periodontitis was associated with more hospitalization (p = 0.009), more days in the intensive care unit (ICU) (p = 0.042), admission to the semi-ICU (p = 0.047), and greater need for oxygen therapy (p = 0.042). After adjustment for confounders, periodontitis resulted in a 1.13-fold increase in the chance of hospitalization. Salivary IL-6 levels (p = 0.010) were increased in individuals with COVID-19 and periodontitis. Periodontitis was associated with increased RANKL and IL-1ß after COVID-19. No significant changes were observed in the bacterial loads of the periodontopathogens Porphyromona gingivalis, Aggregatibacter actinomycetemcomitans, Tanerella forsythia, and Treponema denticola. CONCLUSIONS: Periodontitis was associated with worse COVID-19 outcomes, suggesting the relevance of periodontal care to reduce the burden of overall inflammation. Understanding the crosstalk between SARS-CoV-2 infection and chronic conditions such as periodontitis that can influence disease outcome is important to potentially prevent complications of COVID-19.


Assuntos
COVID-19 , Periodontite Crônica , Periodontite , Humanos , Porphyromonas gingivalis , Interleucina-6 , Estudos de Casos e Controles , SARS-CoV-2 , Periodontite/epidemiologia , Periodontite/microbiologia , Inflamação , Treponema denticola , Periodontite Crônica/microbiologia
18.
Mod Pathol ; 37(2): 100388, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37995913

RESUMO

Cemento-ossifying fibroma (COF) of the jaws is currently classified as a benign mesenchymal odontogenic tumor, and only targeted approaches have been used to assess its genetic alterations. A minimal proportion of COFs harbor CDC73 somatic mutations, and copy number alterations (CNAs) involving chromosomes 7 and 12 have recently been reported in a small proportion of cases. However, the genetic background of COFs remains obscure. We used a combination of whole-exome sequencing and RNA sequencing to assess somatic mutations, fusion transcripts, and CNAs in a cohort of 12 freshly collected COFs. No recurrent fusions have been identified among the 5 cases successfully analyzed by RNA sequencing, with in-frame fusions being detected in 2 cases (MARS1::GOLT1B and PARG::BMS1 in one case and NCLN::FZR1 and NFIC::SAMD1 in the other case) and no candidate fusions identified for the remaining 3 cases. No recurrent pathogenic mutations were detected in the 11 cases that had undergone whole-exome sequencing. A KRAS p.L19F missense variant was detected in one case, and 2 CDC73 deletions were detected in another case. The other variants were of uncertain significance and included variants in PC, ACTB, DOK6, HACE1, and COL1A2 and previously unreported variants in PTPN14, ATP5F1C, APOBEC1, HDAC5, ATF7IP, PARP2, and ACTR3B. The affected genes do not clearly converge on any signaling pathway. CNAs were detected in 5/11 cases (45%), with copy gains involving chromosome 12 occurring in 3/11 cases (27%). In conclusion, no recurrent fusions or pathogenic variants have been detected in the present COF cohort, with copy gains involving chromosome 12 occurring in 27% of cases.


Assuntos
Cementoma , Fibroma Ossificante , Tumores Odontogênicos , Humanos , Cementoma/patologia , Fibroma Ossificante/genética , Tumores Odontogênicos/patologia , Genômica , Proteínas Tirosina Fosfatases não Receptoras , Proteínas Adaptadoras de Transdução de Sinal , Ubiquitina-Proteína Ligases
19.
Ecol Lett ; 27(1): e14351, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38111128

RESUMO

Dominance of neotropical tree communities by a few species is widely documented, but dominant trees show a variety of distributional patterns still poorly understood. Here, we used 503 forest inventory plots (93,719 individuals ≥2.5 cm diameter, 2609 species) to explore the relationships between local abundance, regional frequency and spatial aggregation of dominant species in four main habitat types in western Amazonia. Although the abundance-occupancy relationship is positive for the full dataset, we found that among dominant Amazonian tree species, there is a strong negative relationship between local abundance and regional frequency and/or spatial aggregation across habitat types. Our findings suggest an ecological trade-off whereby dominant species can be locally abundant (local dominants) or regionally widespread (widespread dominants), but rarely both (oligarchs). Given the importance of dominant species as drivers of diversity and ecosystem functioning, unravelling different dominance patterns is a research priority to direct conservation efforts in Amazonian forests.


Assuntos
Ecossistema , Florestas , Humanos , Árvores , Brasil , Biodiversidade
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