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1.
Biodivers Data J ; 8: e50837, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32508509

RESUMO

BACKGROUND: Brazil is one of the most biodiverse countries in the world, with about 37,000 species of land plants. Part of this biodiversity is within protected areas. The development of online databases in the last years greatly improved the available biodiversity data. However, the existing databases do not provide information about the protected areas in which individual plant species occur. The lack of such information is a crucial gap for conservation actions. This study aimed to show how the information captured from online databases, cleaned by a protocol and verified by taxonomists allowed us to obtain a comprehensive list of the vascular plant species from the "Parque Nacional do Itatiaia", the first national park founded in Brazil. All existing records in the online database JABOT (15,100 vouchers) were downloaded, resulting in 11,783 vouchers identified at the species level. Overall, we documented 2,316 species belonging to 176 families and 837 genera of vascular plants in the "Parque Nacional do Itatiaia". Considering the whole vascular flora, 2,238 species are native and 78 are non-native. NEW INFORMATION: The "Parque Nacional do Itatiaia" houses 13% of the angiosperm and 37% of the fern species known from the Brazilian Atlantic Forest. Amongst these species, 82 have been cited as threatened, following IUCN categories (CR, EN or VU), seven are data deficient (DD) and 15 have been classified as a conservation priority, because they are only known from a single specimen collected before 1969.

2.
Neuroscience ; 416: 229-238, 2019 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-31404587

RESUMO

Diabetes is a chronic degenerative disease that represent a major threat to public health worldwide. Once the disease is established, one of the major concerns about the diabetes complications is the development of neuropathy. This study established an experimental model that evaluates the effect of type 1 diabetes on nociceptive challenges in the temporomandibular joint (TMJ). Streptozotocin-induced type 1 (STZ 75 mg/Kg) diabetes inhibited the responsiveness of C-fibers nociceptors located in the TMJ of Wistar rats since seventh day after the disease induction. Diabetes-induced hyporesponsiveness of C-fibers nociceptors was associated with significantly reduction of protein level of neuropeptides Substance P and Calcitonin Gene Related Peptide. Diabetic animals pre-treated with Protein Kinase C (PKC)-α and -ß inhibitor (GO6976) or PKC-ß inhibitor (LY333531) significantly increased capsaicin-induced nociception in the TMJ higher protein levels of Na+/K+-ATPase pump in the trigeminal ganglia. On the other hand, although diabetes inhibits formalin-induced nociception higher protein levels of pro-inflammatory cytokine IL1-ß and chemokine CINC-1/CXCL-1 were observed. Overall, the results of the present work suggest that diabetes causes a hyporesponsiveness of C-fiber and a potentialization of the inflammatory response which may result in the degenerative process of periarticular tissues without pain perception.


Assuntos
Nociceptores/efeitos dos fármacos , Dor/fisiopatologia , Transtornos da Articulação Temporomandibular/fisiopatologia , Articulação Temporomandibular/efeitos dos fármacos , Animais , Capsaicina/farmacologia , Diabetes Mellitus Tipo 1/fisiopatologia , Masculino , Nociceptividade/efeitos dos fármacos , Medição da Dor/métodos , Ratos Wistar , Estreptozocina/farmacologia
3.
Math Biosci Eng ; 13(2): 333-41, 2016 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-27105991

RESUMO

In this work, we present and investigate a multiscale model to simulate 3D growth of glioblastomas (GBMs) that incorporates features of the tumor microenvironment and derives macroscopic growth laws from microscopic tissue structure information. We propose a normalized version of the Shannon entropy as an alternative measure of the directional anisotropy for an estimation of the diffusivity tensor in cases where the latter is unknown. In our formulation, the tumor aggressiveness and morphological behavior is tissue-type dependent, i.e. alterations in white and gray matter regions (which can e.g. be induced by normal aging in healthy individuals or neurodegenerative diseases) affect both tumor growth rates and their morphology. The feasibility of this new conceptual approach is supported by previous observations that the fractal dimension, which correlates with the Shannon entropy we calculate, is a quantitative parameter that characterizes the variability of brain tissue, thus, justifying the further evaluation of this new conceptual approach.


Assuntos
Entropia , Glioblastoma , Modelos Biológicos , Envelhecimento , Anisotropia , Encéfalo/fisiologia , Humanos , Microambiente Tumoral
4.
Can J Physiol Pharmacol ; 92(10): 867-78, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25272090

RESUMO

The disruption to glucose homeostasis upon glucocorticoid (GC) treatment in adult male rats has not been fully characterized in older rats or in females. Thus, we evaluated the age- and gender-related changes in glucose homeostasis in GC-treated rats. We injected male and female rats at 3 months and 12 months of age with either dexamethasone (1.0 mg/kg body mass, intraperitoneally) or saline, daily for 5 days. All of the GC-treated rats had decreased body mass and food intake, and adrenal hypotrophy. Increased glycemia was observed in all of the GC-treated groups and only the 3-month-old female rats were not glucose intolerant. Dexamethasone treatment resulted in hyperinsulinemia and hypertriacylglyceridemia in all of the GC-treated rats. The glucose-stimulated insulin secretion (GSIS) was higher in all of the dexamethasone-treated animals, but it was less pronounced in the older animals. The ß-cell mass was increased in the younger male rats treated with dexamethasone. We conclude that dexamethasone treatment induces glucose intolerance in both the 3- and 12-month-old male rats as well as hyperinsulinemia and augmented GSIS. Three-month-old female rats are protected from glucose intolerance caused by GC, whereas 12-month-old female rats developed the same complications that were present in 3- and 12-month-old male rats.


Assuntos
Anti-Inflamatórios/efeitos adversos , Glucocorticoides/efeitos adversos , Glucose/metabolismo , Imunossupressores/efeitos adversos , Glândulas Suprarrenais/efeitos dos fármacos , Glândulas Suprarrenais/patologia , Fatores Etários , Animais , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Colesterol/sangue , Dexametasona/farmacologia , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Intolerância à Glucose/induzido quimicamente , Homeostase , Hiperinsulinismo/induzido quimicamente , Insulina/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/patologia , Fígado/metabolismo , Masculino , Ratos Wistar , Fatores Sexuais , Triglicerídeos/sangue
5.
Indian J Exp Biol ; 52(10): 972-82, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25345246

RESUMO

Arjunolic acid (AA) obtained from plants of the Combretaceae family has shown anti-diabetic effects. Here, we analyzed whether the diabetogenic effects of dexamethasone (DEX) treatment on glucose homeostasis may be prevented or attenuated by the concomitant administration of AA. Adult Wistar rats were assigned to the following groups: vehicle-treated (Ctl), DEX-treated (1 mg/kg body weight intraperitoneally for 5 days) (Dex), AA-treated (30 mg/kg body weight by oral gavage twice per day) (Aa), AA treatment previous to and concomitant to DEX treatment (AaDex), and AA treatment after initiation of DEX treatment (DexAa). AA administration significantly ameliorated (AaDex) (P > 0.05), but did not attenuate (DexAa), the glucose intolerance induced by DEX treatment. AA did not prevent or attenuate the elevation in hepatic glycogen and triacylglycerol content caused by DEX treatment. All DEX-treated rats exhibited hepatic steatosis that seemed to be more pronounced when associated with AA treatment given for a prolonged period (AaDex). Markers of liver function and oxidative stress were not significantly altered among the groups. Therefore, AA administered for a prolonged period partially prevents the glucose intolerance induced by DEX treatment, but it fails to produce this beneficial effect when given after initiation of GC treatment. Since AA may promote further hepatic steatosis when co-administered with GCs, care is required when considering this phytochemical as a hypoglycemiant and/or insulin-sensitizing agent.


Assuntos
Glicemia/efeitos dos fármacos , Glucocorticoides/sangue , Triterpenos/farmacologia , Animais , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Glucocorticoides/metabolismo , Insulina/metabolismo , Lipídeos/sangue , Fígado/química , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Wistar
6.
PLoS One ; 9(4): e93531, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24705399

RESUMO

Glucocorticoid (GC)-based therapies can cause insulin resistance (IR), glucose intolerance, hyperglycemia and, occasionally, overt diabetes. Understanding the mechanisms behind these metabolic disorders could improve the management of glucose homeostasis in patients undergoing GC treatment. For this purpose, adult rats were treated with a daily injection of dexamethasone (1 mg/kg b.w., i.p.) (DEX) or saline as a control for 5 consecutive days. The DEX rats developed IR, augmented glycemia, hyperinsulinemia and hyperglucagonemia. Treatment of the DEX rats with a glucagon receptor antagonist normalized their blood glucose level. The characteristic inhibitory effect of glucose on glucagon secretion was impaired in the islets of the DEX rats, while no direct effects were found on α-cells in islets that were incubated with DEX in vitro. A higher proportion of docked secretory granules was found in the DEX α-cells as well as a trend towards increased α-cell mass. Additionally, insulin secretion in the presence of glucagon was augmented in the islets of the DEX rats, which was most likely due to their higher glucagon receptor content. We also found that the enzyme 11ßHSD-1, which participates in GC metabolism, contributed to the insulin hypersecretion in the DEX rats under basal glucose conditions. Altogether, we showed that GC treatment induces hyperglucagonemia, which contributes to an imbalance in glucose homeostasis and compensatory ß-cell hypersecretion. This hyperglucagonemia may result from altered α-cell function and, likely, α-cell mass. Additionally, blockage of the glucagon receptor seems to be effective in preventing the elevation in blood glucose levels induced by GC administration.


Assuntos
Glicemia/efeitos dos fármacos , Dexametasona/efeitos adversos , Células Secretoras de Glucagon/fisiologia , Glucocorticoides/efeitos adversos , Homeostase/efeitos dos fármacos , Hiperinsulinismo/induzido quimicamente , Insulina/metabolismo , Animais , Glicemia/metabolismo , Células Cultivadas , Dexametasona/administração & dosagem , Esquema de Medicação , Células Secretoras de Glucagon/efeitos dos fármacos , Células Secretoras de Glucagon/patologia , Glucocorticoides/administração & dosagem , Hiperinsulinismo/sangue , Injeções Intraperitoneais , Resistência à Insulina , Secreção de Insulina , Masculino , Ratos , Ratos Wistar
7.
Appl Physiol Nutr Metab ; 38(11): 1137-46, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24053521

RESUMO

Glucocorticoid (GC) excess alters glucose homeostasis and promotes modifications in murinometric and anthropometric parameters in rodents and humans, respectively. ß-hydroxy-ß-methylbutyrate (HMB), a leucine metabolite, has been proposed as a nutritional strategy for preventing muscle wasting, but few data regarding its effects on glucose homeostasis are available. Here, we analyzed whether the effects of GC excess on glucose homeostasis may be attenuated or exacerbated by the concomitant ingestion of HMB. Adult Wistar rats (90-days-old) were assigned to four groups: (1) vehicle treated (Ctl), (2) dexamethasone (DEX) treated (Dex), (3) HMB treated (Hmb), and (4) DEX plus HMB treated (DexHmb). Dex groups received DEX (1 mg·kg body weight (BW)(-1), intraperitoneal) for 5 consecutive days. HMB groups ingested HMB (320 mg·kg BW(-1), oral gavage) for the same 5 days. HMB ingestion did not attenuate the effects of DEX on food intake and body weight loss, changes in masses of several organs, insulin resistance, and glucose intolerance (p > 0.05). In fact, in DexHmb rats, there was increased fasting glycemia and exacerbated glucose intolerance with the main effect attributed to DEX treatment (p < 0.05). HMB exerted no attenuating effect on plasma triacylglycerol levels from DexHmb rats, but it seems to attenuate the lipolysis induced by ß-adrenergic stimulation (20 µmol·L(-1) isoproterenol) in fragments of retroperitoneal adipose tissue from DexHmb rats. Therefore, HMB does not attenuate the diabetogenic characteristics of GC excess. In fact, the data suggest that HMB may exacerbate GC-induced glucose intolerance.


Assuntos
Intolerância à Glucose , Atrofia Muscular , Animais , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Humanos , Resistência à Insulina , Ratos , Ratos Wistar
8.
Rev Assoc Med Bras (1992) ; 59(1): 85-92, 2013.
Artigo em Inglês, Português | MEDLINE | ID: mdl-23440147

RESUMO

C-reactive protein (CRP) is an acute-phase protein whose requests have been growing exponentially in several countries, including Brazil. In this study, the use of CRP in several clinical situations was reviewed by a group of physicians comprised by specialists in internal medicine, medical emergencies, intensive care, screening, and laboratory medicine, aiming to analyze the applicable literature and to propose guidelines for a more rational use of this laboratory test. The result was the creation of flowcharts guiding CRP request, adjusted to four different healthcare environments, namely, intensive care units, emergency room, wards, and outpatient clinics. These flowcharts, as well as a more detailed discussion on several clinical recommendations for the test, are presented in this study.


Assuntos
Algoritmos , Proteína C-Reativa/análise , Tomada de Decisões/fisiologia , Atenção à Saúde/classificação , Biomarcadores/análise , Humanos
9.
Rev. Assoc. Med. Bras. (1992) ; 59(1): 85-92, jan.-fev. 2013. ilus, tab
Artigo em Português | LILACS | ID: lil-666243

RESUMO

A proteína C reativa (PCR) é uma das proteínas de fase aguda cuja solicitação tem crescido de forma exponencial em vários países, incluindo o Brasil. Neste estudo, a utilidade da PCR em diversas situações clínicas foi revisada por um grupo de médicos composto por especialistas em Medicina Interna, Emergências Médicas, Terapia Intensiva, Rastreamento e Medicina Laboratorial com o objetivo de analisar a literatura pertinente e propor diretrizes para o uso mais racional desse exame laboratorial. O resultado foi a criação de fluxogramas orientadores da solicitação de PCR adaptados a quatro ambientes assistenciais diferentes, sendo eles unidades de terapia intensiva, pronto-socorro, enfermarias e ambulatórios. Esses fluxogramas e uma discussão mais detalhada sobre as diversas indicações clínicas do exame são apresentados neste estudo.


C-reactive protein (CRP) is an acute-phase protein whose requests have been growing exponentially in several countries, including Brazil. In this study, the use of CRP in several clinical situations was reviewed by a group of physicians comprised by specialists in internal medicine, medical emergencies, intensive care, screening, and laboratory medicine, aiming to analyze the applicable literature and to propose guidelines for a more rational use of this laboratory test. The result was the creation of flowcharts guiding CRP request, adjusted to four different healthcare environments, namely, intensive care units, emergency room, wards, and outpatient clinics. These flowcharts, as well as a more detailed discussion on several clinical recommendations for the test, are presented in this study.


Assuntos
Humanos , Algoritmos , Proteína C-Reativa/análise , Tomada de Decisões/fisiologia , Atenção à Saúde/classificação , Biomarcadores/análise
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