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1.
PLoS One ; 18(1): e0280039, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36689405

RESUMO

We conducted research to understand online trade in jaguar parts and develop tools of utility for jaguars and other species. Our research took place to identify potential trade across 31 online platforms in Spanish, Portuguese, English, Dutch, French, Chinese, and Vietnamese. We identified 230 posts from between 2009 and 2019. We screened the images of animal parts shown in search results to verify if from jaguar; 71 posts on 12 different platforms in four languages were accompanied by images identified as definitely jaguar, including a total of 125 jaguar parts (50.7% posts in Spanish, 25.4% Portuguese, 22.5% Chinese and 1.4% French). Search effort varied among languages due to staff availability. Standardizing for effort across languages by dividing number of posts advertising jaguars by search time and number of individual searches completed via term/platform combinations changed the proportions the rankings of posts adjusted for effort were led by Portuguese, Chinese, and Spanish. Teeth were the most common part; 156 posts offered at least 367 teeth and from these, 95 were assessed as definitely jaguar; 71 of which could be linked to a location, with the majority offered for sale from Mexico, China, Bolivia, and Brazil (26.8, 25.4, 16.9, and 12.7% respectively). The second most traded item, skins and derivative items were only identified from Latin America: Brazil (7), followed by Peru (6), Bolivia (3), Mexico (2 and 1 skin piece), and Nicaragua and Venezuela (1 each). Whether by number of posts or pieces, the most commonly parts were: teeth, skins/pieces of skins, heads, and bodies. Our research took place within a longer-term project to assist law enforcement in host countries to better identify potential illegal trade and presents a snapshot of online jaguar trade and methods that also may have utility for many species traded online.


Assuntos
Panthera , Animais , Bolívia , Brasil , México , Peru , Conservação dos Recursos Naturais
2.
FEBS Open Bio ; 12(8): 1509-1522, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35538662

RESUMO

DNA damage induces the activation of many different signals associated with repair or cell death, but it is also connected with physiological events, such as adult neurogenesis and B-cell differentiation. DNA damage induces different signaling pathways, some of them linked to important metabolic changes. The mTORC1 pathway has a central role in the regulation of growth processes and cell division in response to environmental changes and also controls protein synthesis, lipid biogenesis, nucleotide synthesis, and expression of glycolytic genes. Here, we report that double-strand breaks induced with etoposide affect the expression of genes encoding different enzymes associated with specific metabolic pathways in Ramos cells. We also analyzed the role of mTOR signaling, demonstrating that double-strand breaks induce downregulation of mTOR signaling. Specific inhibition of mTORC1 using rapamycin also induced changes in the expression of metabolic genes. Finally, we demonstrated that DNA damage and rapamycin can regulate glucose uptake. In summary, our findings show that etoposide and rapamycin affect the expression of metabolic genes as well as apoptotic and proliferation markers in Ramos cells, increasing our understanding of cancer metabolism.


Assuntos
Dano ao DNA , Serina-Treonina Quinases TOR , Etoposídeo/farmacologia , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/metabolismo
3.
Int J Mol Sci ; 21(11)2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32531922

RESUMO

Agmatine is a neurotransmitter with anticonvulsant, anti-neurotoxic and antidepressant-like effects, in addition it has hypoglycemic actions. Agmatine is converted to putrescine and urea by agmatinase (AGM) and by an agmatinase-like protein (ALP), a new type of enzyme which is present in human and rodent brain tissues. Recombinant rat brain ALP is the only mammalian protein that exhibits significant agmatinase activity in vitro and generates putrescine under in vivo conditions. ALP, despite differing in amino acid sequence from all members of the ureohydrolase family, is strictly dependent on Mn2+ for catalytic activity. However, the Mn2+ ligands have not yet been identified due to the lack of structural information coupled with the low sequence identity that ALPs display with known ureohydrolases. In this work, we generated a structural model of the Mn2+ binding site of the ALP and we propose new putative Mn2+ ligands. Then, we cloned and expressed a sequence of 210 amino acids, here called the "central-ALP", which include the putative ligands of Mn2+. The results suggest that the central-ALP is catalytically active, as agmatinase, with an unaltered Km for agmatine and a decreased kcat. Similar to wild-type ALP, central-ALP is activated by Mn2+ with a similar affinity. Besides, a simple mutant D217A, a double mutant E288A/K290A, and a triple mutant N213A/Q215A/D217A of these putative Mn2+ ligands result on the loss of ALP agmatinase activity. Our results indicate that the central-ALP contains the active site for agmatine hydrolysis, as well as that the residues identified are relevant for the ALP catalysis.


Assuntos
Agmatina/metabolismo , Manganês/metabolismo , Ureo-Hidrolases/química , Ureo-Hidrolases/metabolismo , Animais , Sítios de Ligação , Escherichia coli/genética , Cinética , Mamíferos , Modelos Moleculares , Mutagênese Sítio-Dirigida , Conformação Proteica , Temperatura , Ureo-Hidrolases/genética
4.
Nutrients ; 12(4)2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32272604

RESUMO

Exclusive enteral nutrition (EEN) has been shown to be more effective than corticosteroids in achieving mucosal healing in children with Crohn´s disease (CD) without the adverse effects of these drugs. The aims of this study were to determine the efficacy of EEN in terms of inducing clinical remission in children newly diagnosed with CD, to describe the predictive factors of response to EEN and the need for treatment with biological agents during the first 12 months of the disease. We conducted an observational retrospective multicentre study that included paediatric patients newly diagnosed with CD between 2014-2016 who underwent EEN. Two hundred and twenty-two patients (140 males) from 35 paediatric centres were included, with a mean age at diagnosis of 11.6 ± 2.5 years. The median EEN duration was 8 weeks (IQR 6.6-8.5), and 184 of the patients (83%) achieved clinical remission (weighted paediatric Crohn's Disease activity index [wPCDAI] < 12.5). Faecal calprotectin (FC) levels (µg/g) decreased significantly after EEN (830 [IQR 500-1800] to 256 [IQR 120-585] p < 0.0001). Patients with wPCDAI ≤ 57.5, FC < 500 µg/g, CRP >15 mg/L and ileal involvement tended to respond better to EEN. EEN administered for 6-8 weeks is effective for inducing clinical remission. Due to the high response rate in our series, EEN should be used as the first-line therapy in luminal paediatric Crohn's disease regardless of the location of disease and disease activity.


Assuntos
Doença de Crohn/terapia , Nutrição Enteral , Adolescente , Criança , Doença de Crohn/diagnóstico , Doença de Crohn/metabolismo , Feminino , Humanos , Masculino , Indução de Remissão , Estudos Retrospectivos
5.
J Inorg Biochem ; 202: 110812, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31731096

RESUMO

Ureohydrolases form a conserved family of enzymes with a strict requirement for divalent metal ions for catalytic activity. They catalyze the hydrolysis of the guanidino group and produce urea. In their active sites six highly conserved amino acid residues form a binding pocket for two catalytically essential metal ions that are needed to activate a water molecule to initiate the hydrolysis of the guanidino group in a nucleophilic attack. Focus in this review is on two members of the ureohydrolase family, the Mn2+-dependent arginase and agmatinase, which play important roles in functions related to replication and cell survival. We will focus in particular on Mn2+ binding interactions, and on how this metal ion contributes to the reaction catalyzed by these enzymes. We also include the agmatinase-like protein (ALP) because it is functionally closely related to agmatinase, also requires at least one Mn2+ ion for catalytic activity, but may possess an active site that differs significantly from all other known ureohydrolases.


Assuntos
Arginase , Manganês , Ureo-Hidrolases , Arginase/química , Arginase/metabolismo , Catálise , Manganês/química , Manganês/metabolismo , Ureo-Hidrolases/química , Ureo-Hidrolases/metabolismo
6.
Int J Mol Sci ; 20(13)2019 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-31324056

RESUMO

An important hallmark in cancer cells is the increase in glucose uptake. GLUT1 is an important target in cancer treatment because cancer cells upregulate GLUT1, a membrane protein that facilitates the basal uptake of glucose in most cell types, to ensure the flux of sugar into metabolic pathways. The dysregulation of GLUT1 is associated with numerous disorders, including cancer and metabolic diseases. There are natural products emerging as a source for inhibitors of glucose uptake, and resveratrol is a molecule of natural origin with many properties that acts as antioxidant and antiproliferative in malignant cells. In the present review, we discuss how GLUT1 is involved in the general scheme of cancer cell metabolism, the mechanism of glucose transport, and the importance of GLUT1 structure to understand the inhibition process. Then, we review the current state-of-the-art of resveratrol and other natural products as GLUT1 inhibitors, focusing on those directed at treating different types of cancer. Targeting GLUT1 activity is a promising strategy for the development of drugs aimed at treating neoplastic growth.


Assuntos
Transportador de Glucose Tipo 1/metabolismo , Glucose/metabolismo , Neoplasias/metabolismo , Resveratrol/farmacologia , Animais , Humanos
7.
An. pediatr. (2003. Ed. impr.) ; 88(2): 63-68, feb. 2018. graf, tab
Artigo em Espanhol | IBECS | ID: ibc-172004

RESUMO

Introducción: El fallo hepático agudo (FHA) es una enfermedad multisistémica con afectación severa de la función hepática de aparición brusca. La puntuación Pediatric End-stage Liver Disease (PELD) es un predictor de mortalidad en hepatopatías crónicas, siendo la experiencia en FHA limitada. Objetivos: Evaluar las características etiológicas y la evolución de niños con FHA en un centro con trasplante hepático (TH) infantil e investigar la validez del PELD como indicador pronóstico. Pacientes y métodos: Estudio retrospectivo de pacientes con FHA en nuestro centro de 2000 a 2013 según criterios del grupo de trabajo de FHA. Resultados: Se reclutaron 49 pacientes (0-14 años). Las etiologías más frecuentes fueron la indeterminada (36,7%) y la metabólica (26,5%). Los pacientes que requirieron TH fueron el 42,8%, y el 16,3% fallecieron. Los pacientes con cifras elevadas de bilirrubina, INR o que desarrollaron encefalopatía tuvieron más probabilidades de presentar una evolución tórpida, obteniéndose una OR para el INR de 1,93. Un punto de corte de 27 en el PELD según la curva ROC mostró una sensibilidad del 86% y una especificidad del 85% de presentar evolución desfavorable (ABC: 0,90; p < 0,001). La supervivencia de FHA sin necesidad de TH fue más probable en aquellos con valores de PELD bajos y que no desarrollaron encefalopatía, con un RR de 0,326. Conclusiones: Los pacientes con FHA que presentaron un PELD elevado junto con encefalopatía tuvieron peor evolución. El valor del PELD puede ayudar a establecer el momento óptimo para inclusión en lista de TH; sin embargo son necesarios estudios a mayor escala (AU)


Introduction: Acute liver failure (ALF) is a multisystem disease with severe impairment of liver function of acute onset. The Paediatric End-stage Liver Disease (PELD) score is used as a predictor of mortality in chronic liver disease, however experience is limited in ALF. Objectives: To evaluate the aetiology and outcomes of children with ALF in a Children's Liver Transplant Centre, and to investigate the validity of PELD as a prognostic indicator. Patients and methods: A retrospective study was conducted on patients diagnosed with ALF in our hospital from 2000 to 2013 using the criteria of the Paediatric ALF Study Group. Results: The study included 49 patients with an age range 0-14 years. The most frequent aetiologies were: indeterminate (36.7%) and metabolic (26.5%). Liver transplant (LT) was required by 42.8%, and there were 16.3% deaths. Patients with higher levels of bilirubin, INR, or encephalopathy were more likely to require a liver transplant, yielding an OR for INR 1.93. A cut-off of 27 in the PELD score according to the ROC curve showed a sensitivity of 86% and a specificity of 85%, predicting a worse outcome (AUC: 0.90; P < .001). The survival of patients with ALF without transplantation seems more likely in those who have low values of PELD and absence of encephalopathy, with a RR of 0.326. Conclusions: ALF patients with a high PELD score and the presence of encephalopathy had worse outcomes. The PELD score could be a useful tool to establish the optimum time for inclusion in the transplant list, however further studies are still needed (AU)


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Adolescente , Falência Hepática/cirurgia , Transplante de Fígado/métodos , Encefalopatia Hepática/complicações , Estudos Retrospectivos , Falência Hepática Aguda/etiologia , Prognóstico
8.
Metabolism ; 81: 35-44, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29162499

RESUMO

Agmatine (1-amino-4-guanidinobutane), a precursor for polyamine biosynthesis, has been identified as an important neuromodulator with anticonvulsant, antineurotoxic and antidepressant actions in the brain. In this context it has emerged as an important mediator of addiction/satiety pathways associated with alcohol misuse. Consequently, the regulation of the activity of key enzymes in agmatine metabolism is an attractive strategy to combat alcoholism and related addiction disorders. Agmatine results from the decarboxylation of L-arginine in a reaction catalyzed by arginine decarboxylase (ADC), and can be converted to either guanidine butyraldehyde by diamine oxidase (DAO) or putrescine and urea by the enzyme agmatinase (AGM) or the more recently identified AGM-like protein (ALP). In rat brain, agmatine, AGM and ALP are predominantly localised in areas associated with roles in appetitive and craving (drug-reinstatement) behaviors. Thus, inhibitors of AGM or ALP are promising agents for the treatment of addictions. In this review, the properties of DAO, AGM and ALP are discussed with a view to their role in the agmatine metabolism in mammals.


Assuntos
Agmatina/metabolismo , Neurotransmissores/metabolismo , Amina Oxidase (contendo Cobre)/fisiologia , Animais , Carboxiliases/fisiologia , Humanos , Ureo-Hidrolases/fisiologia
9.
J Immigr Minor Health ; 20(5): 1236-1242, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28825172

RESUMO

Hispanic populations have low HPV vaccination rates, although the vaccine is safe and efficacious. We surveyed a low-income Hispanic population to characterize knowledge gaps about the HPV vaccine and understand factors associated with the decision to vaccinate a child to determine how physicians can enhance vaccination rates. Surveys in English and Spanish were distributed to parents of children under age 18. Statistical analysis included logistic regression. Knowledge that the vaccine can prevent invasive cervical cancer most impacted intent to vaccinate. Physician recommendation to vaccinate was far more influential in a parent's decision compared to TV and other sources. Girls are more likely to receive the HPV vaccine over boys. While physician recommendation is critical, they have minimal time for education. Our results suggest that physicians should focus on the vaccine's link to cancer prevention, leaving other knowledge areas for the interdisciplinary care team.


Assuntos
Hispânico ou Latino/psicologia , Vacinas contra Papillomavirus/administração & dosagem , Pais/psicologia , Papel do Médico , Médicos de Atenção Primária , Adolescente , Criança , Informação de Saúde ao Consumidor/métodos , Feminino , Conhecimentos, Atitudes e Prática em Saúde/etnologia , Humanos , Modelos Logísticos , Masculino , Infecções por Papillomavirus/prevenção & controle , Aceitação pelo Paciente de Cuidados de Saúde/etnologia , Pobreza , Fatores de Risco , Fatores Sexuais , Texas , Neoplasias do Colo do Útero/prevenção & controle
10.
An Pediatr (Engl Ed) ; 88(2): 63-68, 2018 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-28395968

RESUMO

INTRODUCTION: Acute liver failure (ALF) is a multisystem disease with severe impairment of liver function of acute onset. The Paediatric End-stage Liver Disease (PELD) score is used as a predictor of mortality in chronic liver disease, however experience is limited in ALF. OBJECTIVES: To evaluate the aetiology and outcomes of children with ALF in a Children's Liver Transplant Centre, and to investigate the validity of PELD as a prognostic indicator. PATIENTS AND METHODS: A retrospective study was conducted on patients diagnosed with ALF in our hospital from 2000 to 2013 using the criteria of the Paediatric ALF Study Group. RESULTS: The study included 49 patients with an age range 0-14years. The most frequent aetiologies were: indeterminate (36.7%) and metabolic (26.5%). Liver transplant (LT) was required by 42.8%, and there were 16.3% deaths. Patients with higher levels of bilirubin, INR, or encephalopathy were more likely to require a liver transplant, yielding an OR for INR 1.93. A cut-off of 27 in the PELD score according to the ROC curve showed a sensitivity of 86% and a specificity of 85%, predicting a worse outcome (AUC: 0.90; P<.001). The survival of patients with ALF without transplantation seems more likely in those who have low values of PELD and absence of encephalopathy, with a RR of 0.326. CONCLUSIONS: ALF patients with a high PELD score and the presence of encephalopathy had worse outcomes. The PELD score could be a useful tool to establish the optimum time for inclusion in the transplant list, however further studies are still needed.


Assuntos
Falência Hepática Aguda , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Falência Hepática Aguda/diagnóstico , Falência Hepática Aguda/etiologia , Falência Hepática Aguda/cirurgia , Transplante de Fígado , Masculino , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento
11.
Molecules ; 23(1)2017 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-29267250

RESUMO

Resveratrol is a polyphenolic natural compound produced by a variety of crops. Currently, resveratrol is considered a multi-target anti-cancer agent with pleiotropic activity, including the ability to prevent the proliferation of malignant cells by inhibiting angiogenesis and curtailing invasive and metastatic factors in many cancer models. However, the molecular mechanisms mediating resveratrol-specific effects on lymphoma cells remain unknown. To begin tackling this question, we treated the Burkitt's lymphoma cell line Ramos with resveratrol and assessed cell survival and gene expression. Our results suggest that resveratrol shows a significant anti-proliferative and pro-apoptotic activity on Ramos cells, inducing the DNA damage response, DNA repairing, and modulating the expression of several genes that regulate the apoptotic process and their proliferative activity.


Assuntos
Antineoplásicos/química , Resveratrol/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linfoma de Burkitt , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Humanos , Resveratrol/farmacologia
12.
Molecules ; 22(3)2017 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-28272357

RESUMO

Resveratrol-a polyphenol of natural origin-has been the object of massive research in the past decade because of its potential use in cancer therapy. However, resveratrol has shown an extensive range of cellular targets and effects, which hinders the use of the molecule for medical applications including cancer and type 2 diabetes. Here, we review the latest advances in understanding how resveratrol modulates glucose uptake, regulates cellular metabolism, and how this may be useful to improve current therapies. We discuss challenges and findings regarding the inhibition of glucose uptake by resveratrol and other polyphenols of similar chemical structure. We review alternatives that can be exploited to improve cancer therapies, including the use of other polyphenols, or the combination of resveratrol with other molecules and their impact on glucose homeostasis in cancer and diabetes.


Assuntos
Metabolismo dos Carboidratos/efeitos dos fármacos , Glucose/metabolismo , Estilbenos/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Transporte Biológico/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Sinergismo Farmacológico , Homeostase/efeitos dos fármacos , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Polifenóis/química , Polifenóis/farmacologia , Polifenóis/uso terapêutico , Resveratrol , Transdução de Sinais/efeitos dos fármacos , Estilbenos/química , Estilbenos/uso terapêutico
13.
J Cell Biochem ; 118(6): 1330-1340, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27862234

RESUMO

Interleukin-3 (IL-3) is a well-characterized growth factor in hematopoietic cells, but it is also expressed in other cell types with poorly described functions. Many studies have provided evidence that IL-3 plays an important role in cell survival. We have previously shown that IL-3 is able to increase glucose uptake in HEK293 cells, suggesting that this factor requires sustained glucose metabolism to promote cell survival. In this study, we demonstrate that IL-3 contributes to cell survival under oxidative stress, a prominent feature in the pathophysiology of cancer, diabetes, and neurodegenerative diseases, as well as in the aging process. Our results suggest a molecular mechanism that involves signaling pathways mediated by PI-3k/Akt and Erk. Altogether, these findings show an important role for IL-3 in supporting the viability of non-hematopoietic systems. J. Cell. Biochem. 118: 1330-1340, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Glucose/metabolismo , Peróxido de Hidrogênio/efeitos adversos , Interleucina-3/metabolismo , Morte Celular , Sobrevivência Celular/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células HEK293 , Humanos , Estresse Oxidativo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos
14.
FEBS Open Bio ; 6(10): 1000-1007, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27761359

RESUMO

The polyphenol nordihydroguaiaretic acid (NDGA) has antineoplastic properties, hence it is critical to understand its action at the molecular level. Here, we establish that NDGA inhibits glucose uptake and cell viability in leukemic HL-60 and U-937 cell lines. We monitored hexose uptake using radio-labeled 2-deoxyglucose (2DG) and found that the inhibition by NDGA followed a noncompetitive mechanism. In addition, NDGA blocked hexose transport in human red blood cells and displaced prebound cytochalasin B from erythrocyte ghosts, suggesting a direct interaction with the glucose transporter GLUT1. We propose a model for the mechanism of action of NDGA on glucose uptake. Our study shows for the first time that NDGA can act as inhibitor of the glucose transporter GLUT1.

15.
Acta biol. colomb ; 21(1): 151-166, Jan.-Apr. 2016. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-769042

RESUMO

La cacería de subsistencia ha sido una actividad de vital importancia para las comunidades indígenas como fuente de proteína y venta. Se caracterizó la cacería de subsistencia realizada por comunidades de las etnias Piaroa y Curripaco presentes en la Reserva de Biosfera el Tuparro, por medio de registros de caza durante nueve meses de estudio. Se encontró que no hay diferencias significativas en cuanto a especies y número de individuos cazados entre las dos etnias, siendo Artiodactyla y Rodentia los órdenes con mayor aporte respecto al número de individuos, biomasa y riqueza de especies, lo cual fue similar a otros estudios realizados en el Neotrópico. Los Piaroa cazan más frecuentemente cuando los estudiantes llegan de la ciudad al resguardo, mientras que los Curripaco lo hacen para las reuniones evangélicas. El arte de caza más usado por las comunidades de las dos etnias fue la escopeta. Las etnias estudiadas tienen sus zonas de caza en la Reserva de Biósfera El Tuparro, y en ellas, los Curripaco están aprovechando directamente los recursos de su zona núcleo del Parque Nacional Natural El Tuparro.


Subsistence hunting has been an activity of vital importance to indigenous communities as a source of protein and sale. We characterized subsistence hunting by Curripaco and Piaroa ethnic groups present in the Tuparro Biosphere Reserve, through hunting records over nine months of study. We found no significant differences in species and number of individuals hunted by the two ethnic groups. The orders Rodentia and Artiodactyla contributed the most in terms of number of individuals, biomass and species richness, which was similar to studies to the Neotropics. The Piaroa hunt more frequently when students return to the community lands from the city, while the Curripaco do so for religious gatherings. The hunting method used most often by both ethnic groups was the shotgun. The hunting areas used by ethnic groups are within the RBT, and the Curripaco are utilizing the resources of the Tuparro Natural National Park, the core area.

16.
Am J Physiol Cell Physiol ; 305(1): C90-9, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23615963

RESUMO

Resveratrol acts as a chemopreventive agent for cancer and as a potential antiobesity and antidiabetic compound, by leading to reduced body fat and improved glucose homeostasis. The exact mechanisms involved in improving hyperglycemic state are not known, but most of the glucose uptake into mammalian cells is facilitated by the GLUT hexose transporters. Resveratrol is structurally similar to isoflavones such as genistein, which inhibit the glucose uptake facilitated by the GLUT1 hexose transporter. Here we examined the direct effects of resveratrol on glucose uptake and accumulation in HL-60 and U-937 leukemic cell lines, which express mainly GLUT1, under conditions that discriminate transport from the intracellular substrate phosphorylation/accumulation. Resveratrol blocks GLUT1-mediated hexose uptake and thereby affects substrate accumulation on these cells. Consequently, we characterized the mechanism involved in inhibition of glucose uptake in human red cells. Resveratrol inhibits glucose exit in human red cells, and the displacement of previously bound cytochalasin B revealed the direct interaction of resveratrol with GLUT1. Resveratrol behaves as a competitive blocker of glucose uptake under zero-trans exit and exchange kinetic assays, but it becomes a mixed noncompetitive blocker when zero-trans entry transport was assayed, suggesting that the binding site for resveratrol lies on the endofacial face of the transporter. We propose that resveratrol interacts directly with the human GLUT1 hexose transporter by binding to an endofacial site and that this interaction inhibits the transport of hexoses across the plasma membrane. This inhibition is distinct from the effect of resveratrol on the intracellular phosphorylation/accumulation of glucose.


Assuntos
Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Transportador de Glucose Tipo 1/metabolismo , Glucose/metabolismo , Estilbenos/farmacologia , Relação Dose-Resposta a Droga , Transportador de Glucose Tipo 1/genética , Células HL-60 , Humanos , Resveratrol , Células U937
17.
Medicina (B Aires) ; 72(5): 367-70, 2012.
Artigo em Espanhol | MEDLINE | ID: mdl-23089111

RESUMO

In order to evaluate the frequency of a late clinical stage in HIV infected patients at onset of antiretroviral therapy (LART) and to identify possible associated factors, we performed a retrospective analysis of data reported in two prospective cohorts of HIV infected patients who started antiretroviral therapy for the first time between 2005 and 2009. Medical records of 265 patients -123 women (46.6%) and 141 men, median age 37.7 years old- were analyzed. LART was observed in 132 cases (50%), out of them 102 (77.2%) were associated to late diagnosis of HIV infection and 30 (22.8%) to patients that had not been retained in HIV care. The median of CD4 was 120 cells/ml and that of viral load 58 038 copies/ml. CD4 cells count was below 200 cells/ml in 174 patients (71.3%). There was a higher incidence of LART in men than in women (59.8% and 42.2% respectively). Diagnosis in women took place during pregnancy control in 25:2% of the cases. High alcohol consumption (p 0.006), single hood (p 0.04) and level of education lower than secondary (p 0.008) were associated to LART at bivariate analysis. Male sex (p 0.003) was the only associated factor both in bivariate and multivariate analysis. Our data reinforce the need of expanding HIV testing and should assist programs to define actions promoting early entry in HIV care.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , HIV/imunologia , Adolescente , Adulto , Contagem de Linfócito CD4 , Diagnóstico Tardio , Feminino , Infecções por HIV/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Estudos Retrospectivos , Fatores Sexuais , Fatores Socioeconômicos , Carga Viral , Adulto Jovem
18.
Medicina (B.Aires) ; 72(5): 367-370, oct. 2012. tab
Artigo em Espanhol | LILACS | ID: lil-657531

RESUMO

A fin de evaluar la frecuencia y posibles factores asociados a la presencia de estadio clínico avanzado al inicio de terapia antirretroviral (ECAITA), efectuamos un análisis retrospectivo de datos de dos cohortes prospectivas de pacientes infectados por HIV que iniciaron terapia antirretroviral (sin tratamiento anterior) entre 2005 y 2009. Se analizaron las historias clínicas de 264 pacientes, 123 mujeres (46.6%) y 141 hombres (53.4%). La mediana de edad fue de 37.7 años. Observamos ECAITA en 132 casos (50%), de los cuales 102 (77.2%) se asociaron a diagnóstico tardío de infección por HIV y 30 (22.8%) a pacientes con diagnóstico previo no retenidos en el cuidado clínico de la salud. La mediana de células CD4 fue 120/ml y de carga viral 58 038 copias/ml. El recuento de células CD4 era inferior a 200 cel/ml en 174 pacientes (71.3%). Los hombres presentaron ECAITA con mayor frecuencia que las mujeres (59.8% vs. 40.2%), en quienes el diagnóstico se realizó durante el control de un embarazo en el 25.2% de los casos. Consumo elevado de alcohol (p 0.006), ser soltero (p 0.04) y nivel de educación menor al secundario completo (p 0.008) se asociaron a ECAITA en el análisis bivariado. Ser de sexo masculino (p 0.003) fue el único factor asociado tanto en el análisis bivariado como en el multivariado. Nuestros datos refuerzan la necesidad de expandir el testeo para HIV y deberían impulsar a definir acciones programáticas que promuevan el ingreso precoz al cuidado de la infección por HIV.


In order to evaluate the frequency of a late clinical stage in HIV infected patients at onset of antiretroviral therapy (LART) and to identify possible associated factors, we performed a retrospective analysis of data reported in two prospective cohorts of HIV infected patients who started antiretroviral therapy for the first time between 2005 and 2009. Medical records of 265 patients -123 women (46.6%) and 141 men, median age 37.7 years old- were analyzed. LART was observed in 132 cases (50%), out of them 102 (77.2%) were associated to late diagnosis of HIV infection and 30 (22.8%) to patients that had not been retained in HIV care. The median of CD4 was 120 cells/ml and that of viral load 58 038 copies/ml. CD4 cells count was below 200 cells/ml in 174 patients (71.3%). There was a higher incidence of LART in men than in women (59.8% and 42.2% respectively). Diagnosis in women took place during pregnancy control in 25:2% of the cases. High alcohol consumption (p 0.006), single hood (p 0.04) and level of education lower than secondary (p 0.008) were associated to LART at bivariate analysis. Male sex (p 0.003) was the only associated factor both in bivariate and multivariate analysis. Our data reinforce the need of expanding HIV testing and should assist programs to define actions promoting early entry in HIV care.


Assuntos
Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Terapia Antirretroviral de Alta Atividade , Fármacos Anti-HIV/uso terapêutico , HIV , Infecções por HIV/tratamento farmacológico , Diagnóstico Tardio , Infecções por HIV/diagnóstico , Razão de Chances , Estudos Retrospectivos , Fatores Sexuais , Fatores Socioeconômicos , Carga Viral
19.
Medicina (B.Aires) ; 72(5): 367-370, oct. 2012. tab
Artigo em Espanhol | BINACIS | ID: bin-129307

RESUMO

A fin de evaluar la frecuencia y posibles factores asociados a la presencia de estadio clínico avanzado al inicio de terapia antirretroviral (ECAITA), efectuamos un análisis retrospectivo de datos de dos cohortes prospectivas de pacientes infectados por HIV que iniciaron terapia antirretroviral (sin tratamiento anterior) entre 2005 y 2009. Se analizaron las historias clínicas de 264 pacientes, 123 mujeres (46.6%) y 141 hombres (53.4%). La mediana de edad fue de 37.7 años. Observamos ECAITA en 132 casos (50%), de los cuales 102 (77.2%) se asociaron a diagnóstico tardío de infección por HIV y 30 (22.8%) a pacientes con diagnóstico previo no retenidos en el cuidado clínico de la salud. La mediana de células CD4 fue 120/ml y de carga viral 58 038 copias/ml. El recuento de células CD4 era inferior a 200 cel/ml en 174 pacientes (71.3%). Los hombres presentaron ECAITA con mayor frecuencia que las mujeres (59.8% vs. 40.2%), en quienes el diagnóstico se realizó durante el control de un embarazo en el 25.2% de los casos. Consumo elevado de alcohol (p 0.006), ser soltero (p 0.04) y nivel de educación menor al secundario completo (p 0.008) se asociaron a ECAITA en el análisis bivariado. Ser de sexo masculino (p 0.003) fue el único factor asociado tanto en el análisis bivariado como en el multivariado. Nuestros datos refuerzan la necesidad de expandir el testeo para HIV y deberían impulsar a definir acciones programáticas que promuevan el ingreso precoz al cuidado de la infección por HIV.(AU)


In order to evaluate the frequency of a late clinical stage in HIV infected patients at onset of antiretroviral therapy (LART) and to identify possible associated factors, we performed a retrospective analysis of data reported in two prospective cohorts of HIV infected patients who started antiretroviral therapy for the first time between 2005 and 2009. Medical records of 265 patients -123 women (46.6%) and 141 men, median age 37.7 years old- were analyzed. LART was observed in 132 cases (50%), out of them 102 (77.2%) were associated to late diagnosis of HIV infection and 30 (22.8%) to patients that had not been retained in HIV care. The median of CD4 was 120 cells/ml and that of viral load 58 038 copies/ml. CD4 cells count was below 200 cells/ml in 174 patients (71.3%). There was a higher incidence of LART in men than in women (59.8% and 42.2% respectively). Diagnosis in women took place during pregnancy control in 25:2% of the cases. High alcohol consumption (p 0.006), single hood (p 0.04) and level of education lower than secondary (p 0.008) were associated to LART at bivariate analysis. Male sex (p 0.003) was the only associated factor both in bivariate and multivariate analysis. Our data reinforce the need of expanding HIV testing and should assist programs to define actions promoting early entry in HIV care.(AU)


Assuntos
Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , HIV/imunologia , Contagem de Linfócito CD4 , Diagnóstico Tardio , Infecções por HIV/diagnóstico , Razão de Chances , Estudos Retrospectivos , Fatores Sexuais , Fatores Socioeconômicos , Carga Viral
20.
Am J Physiol Cell Physiol ; 303(5): C530-9, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22673619

RESUMO

Glucose transporter (GLUT)1 has become an attractive target to block glucose uptake in malignant cells since most cancer cells overexpress GLUT1 and are sensitive to glucose deprivation. Methylxanthines are natural compounds that inhibit glucose uptake; however, the mechanism of inhibition remains unknown. Here, we used a combination of binding and glucose transport kinetic assays to analyze in detail the effects of caffeine, pentoxifylline, and theophylline on hexose transport in human erythrocytes. The displacement of previously bound cytochalasin B revealed a direct interaction between the methylxanthines and GLUT1. Methylxanthines behave as noncompetitive blockers (inhibition constant values of 2-3 mM) in exchange and zero-trans efflux assays, whereas mixed inhibition with a notable uncompetitive component is observed in zero-trans influx assays (inhibition constant values of 5-12 mM). These results indicate that methylxanthines do not bind to either exofacial or endofacial d-glucose-binding sites but instead interact at a different site accessible by the external face of the transporter. Additionally, infinite-cis exit assays (Sen-Widdas assays) showed that only pentoxifylline disturbed d-glucose for binding to the exofacial substrate site. Interestingly, coinhibition assays showed that methylxanthines bind to a common site on the transporter. We concluded that there is a methylxanthine regulatory site on the external surface of the transporter, which is close but distinguishable from the d-glucose external site. Therefore, the methylxanthine moiety may become an attractive framework for the design of novel specific noncompetitive facilitative GLUT inhibitors.


Assuntos
Transportador de Glucose Tipo 1/antagonistas & inibidores , Transportador de Glucose Tipo 1/metabolismo , Xantinas/farmacologia , Sítios de Ligação , Transporte Biológico , Membrana Celular , Citocalasina B/metabolismo , Desoxiglucose/metabolismo , Eritrócitos/metabolismo , Glucose/metabolismo , Humanos , Conformação Proteica , Xantinas/classificação
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