901 research outputs found
Molecular and serological diagnosis of toxoplasmosis: a systematic review and meta-analysis
Toxoplasmosis is an infection of vast worldwide distribution whose etiologic agent is Toxoplasma gondii. This disease can cause problems ranging from mild symptoms to serious conditions, such as encephalitis, miscarriage and blindness. Therefore, it is of utmost importance to perform a diagnosis with reproducible techniques in order to obtain a good prognosis. The aim of this review was to analyze the efficiency of toxoplasmosis diagnostic techniques based on sensitivity and specificity results. Five research platforms in English language were used (Eric, Elsevier, Google Scholar, PubMed and SciELO), which contained data on the diagnosis of toxoplasmosis. The search and selection were performed for studies published prior to June 2021. The search resulted in the inclusion of 13 articles published from 2005 to 2020. The data revealed the use of different samples in the standardization of techniques such as serum, total blood, colostrum and amniotic fluid. The flow cytometry, lateral flow immunoassay and qPCR techniques showed 100% sensitivity, whereas the ELISA, western blotting, qPCR and RE-LAMP techniques achieved 100% specificity. Significantly, the qPCR and LAMP techniques were more accurate when the likelihood ratio was assessed. The meta-analysis identified that ISAGA and western blotting have low sensitivity values and LIASON, ELFA and ELISA, using a silica bioconjugate, also have low specificity values. It was noted that a wide range of methods have high values of sensitivity and specificity. Therefore, the choice of the method will be based on the conditions and its financial viability
Perspectivas Atuais sobre Terapias para a Doença de Parkinson: Uma Análise da Literatura Contemporânea
Parkinson's disease (PD) is a complex neurodegenerative condition characterized by debilitating motor and non-motor symptoms resulting from the progressive loss of dopaminergic neurons. This text reviews a variety of emerging therapeutic strategies for PD, ranging from stem cell-based therapies to novel pharmacological approaches, such as the use of antidiabetic agents and modulation of the kynurenine enzymatic system. While these approaches offer hope for halting disease progression, they face ethical, technical, and clinical challenges that need to be addressed to ensure their clinical success. Additionally, technologies like wearables and motion analysis offer innovative ways to monitor and optimize PD treatment, though they also present standardization and correlation challenges with other disease markers. Ultimately, a multidisciplinary and careful approach, coupled with robust clinical trials, is essential to realize the full potential of these interventions and improve the quality of life for patients with PD and other neurodegenerative conditions. A doença de Parkinson (DP) é uma condição neurodegenerativa complexa, caracterizada por sintomas motores e não motores debilitantes, resultantes da perda progressiva de neurônios dopaminérgicos. Este texto revisa uma variedade de estratégias terapêuticas emergentes para a DP, abordando desde terapias baseadas em células-tronco até novos enfoques farmacológicos, como o uso de agentes antidiabéticos e a modulação do sistema enzimático quinurenina. Embora essas abordagens ofereçam esperança para interromper a progressão da doença, enfrentam desafios éticos, técnicos e clínicos que precisam ser abordados para garantir seu sucesso clínico. Além disso, tecnologias como wearables e análise de movimento oferecem maneiras inovadoras de monitorar e otimizar o tratamento da DP, embora também apresentem desafios de padronização e correlação com outros marcadores de doenças. Em última análise, uma abordagem multidisciplinar e cuidadosa, juntamente com ensaios clínicos robustos, é essencial para realizar todo o potencial dessas intervenções e melhorar a qualidade de vida dos pacientes com DP e outras condições neurodegenerativas
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4
While the increasing availability of global databases on ecological communities has advanced our knowledge
of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In
the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of
Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus
crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced
environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian
Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by
2050. This means that unless we take immediate action, we will not be able to establish their current status,
much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost
Rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART): Study protocol for a randomized controlled trial
Background: Acute respiratory distress syndrome (ARDS) is associated with high in-hospital mortality. Alveolar recruitment followed by ventilation at optimal titrated PEEP may reduce ventilator-induced lung injury and improve oxygenation in patients with ARDS, but the effects on mortality and other clinical outcomes remain unknown. This article reports the rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART). Methods/Design: ART is a pragmatic, multicenter, randomized (concealed), controlled trial, which aims to determine if maximum stepwise alveolar recruitment associated with PEEP titration is able to increase 28-day survival in patients with ARDS compared to conventional treatment (ARDSNet strategy). We will enroll adult patients with ARDS of less than 72 h duration. The intervention group will receive an alveolar recruitment maneuver, with stepwise increases of PEEP achieving 45 cmH(2)O and peak pressure of 60 cmH2O, followed by ventilation with optimal PEEP titrated according to the static compliance of the respiratory system. In the control group, mechanical ventilation will follow a conventional protocol (ARDSNet). In both groups, we will use controlled volume mode with low tidal volumes (4 to 6 mL/kg of predicted body weight) and targeting plateau pressure <= 30 cmH2O. The primary outcome is 28-day survival, and the secondary outcomes are: length of ICU stay; length of hospital stay; pneumothorax requiring chest tube during first 7 days; barotrauma during first 7 days; mechanical ventilation-free days from days 1 to 28; ICU, in-hospital, and 6-month survival. ART is an event-guided trial planned to last until 520 events (deaths within 28 days) are observed. These events allow detection of a hazard ratio of 0.75, with 90% power and two-tailed type I error of 5%. All analysis will follow the intention-to-treat principle. Discussion: If the ART strategy with maximum recruitment and PEEP titration improves 28-day survival, this will represent a notable advance to the care of ARDS patients. Conversely, if the ART strategy is similar or inferior to the current evidence-based strategy (ARDSNet), this should also change current practice as many institutions routinely employ recruitment maneuvers and set PEEP levels according to some titration method.Hospital do Coracao (HCor) as part of the Program 'Hospitais de Excelencia a Servico do SUS (PROADI-SUS)'Brazilian Ministry of Healt
Protective effect of N-acetylcysteine on the nephrotoxicity of contrast media based on gadolinium in an experimental model of chronic kidney disease
INTRODUÇÃO: O Gadolínio (Gd) é um raro metal da classe dos lantanídios usado como meio de contraste devido as suas propriedades paramagnéticas. Após sua descoberta, foi considerado um contraste pouco nefrotóxico em pacientes com doença renal crônica (DRC). Atualmente, existem evidências de que o Gd pode apresentar nefrotoxicidade semelhante aos contrastes iodados. A administração de Gadolínio em ratos com DRC pode levar a piora da função renal aferida por clearance de inulina e mobilização do ferro corporal gerando stress oxidativo. OBJETIVOS: O objetivo do estudo foi avaliar o efeito do Gd na função renal, nos parâmetros de cinética do ferro em ratos com DRC e o possível efeito protetor do anti-oxidante N-Acetilcisteína (NAC). MATERIAIS E MÉTODOS: Ratos Wistar machos foram submetidos à nefrectomia 5/6 (Nx) para induzir DRC. Gadoterate Meglumine, um contraste à base de Gadolínio iônico e macrocíclico foi administrado via intravenosa na dose de 1,5mmol/kg de peso de rato 21 dias após a nefrectomia. Para avaliar o efeito do Gd sobre a função renal, estudos de clearance de inulina foram realizados em 4 grupos de ratos 48 hs após a aplicação do Gd: grupo controle 1- Nx (n=7); 2- Nx+NAC (n=6); 3- Nx+Gd (n=8); 4- Nx+Gd+NAC (n=5). O NAC foi administrado no grupo 4 diluído em água 48 hs antes e 48 hs depois da administração do Gd na dose de 4800mg/l. O grupo 2 recebeu NAC durante o mesmo período de tempo do grupo 4. O Gd também foi administrado em ratos com função renal normal, grupo Normal (n=8) na mesma dose dos grupos nefrectomizados com avaliação da função renal e proteinúria. Além da taxa de filtração glomerular (TFG), foram avaliados: proteinúria de 24hs (ptn), parâmetros de gaiola metabólica, pressão arterial (PA), paramêtros de cinética do ferro representados pelo ferro sérico (Fe), capacidade total de ligação do ferro (CTLF), saturação de transferrina, ferritina sérica e stress oxidativo por meio da dosagem de espécies reativas ao ácido tiobarbitúrico (TBARS). Os dados foram submetidos à análise de variância ANOVA utilizando o programa Graph Prism com nível de significância p<0,05 e erro padrão. RESULTADOS: A aplicação de Gd em ratos nefrectomizados resultou em queda na TFG no grupo 3 em relação ao grupo controle 1 (p<0,01). Houve uma tendência de aumento da ptn no grupo 3 em relação aos demais grupos. O grupo 4 que recebeu tratamento com NAC apresentou TFG e ptn semelhante ao grupo 1 e TFG estatisticamente maior que o grupo 3 (p<0,05). Com relação ao grupo de ratos normais não houve alteração da TFG nem aumento de ptn após a aplicação do Gd em relação à ratos não nefrectomizados que não receberam contraste. Com relação aos parâmetros da cinética do ferro, o grupo 3 apresentou elevação da ferritina e da saturação da transferrina comparados ao grupo 1 (p<0,05) e (p<0,01) respectivamente. Houve diminuição da capacidade total de ligação do ferro (CTLF) no grupo 3 comparado ao grupo 1(p<0,01). O uso profilático do NAC no grupo 4 reverteu todas as alterações descritas anteriormente no grupo 3 com significância estatística (p<0,05), (p<0,01) e (p<0,01) respectivamente. Com relação ao stress oxidativo, o grupo 3 apresentou níveis de TBARS significativamente maiores que o grupo 1 (p<0,05). O grupo 4 apresentou níveis de TBARS semelhantes ao grupo 1 e menores que o grupo 3 (p<0,05). O grupo 2 que recebeu apenas NAC por curto período de tempo apresentou TFG, Ptn e parâmetros de cinética de ferro semelhantes aos grupos 1 e 4. Com relação aos dados de gaiola metabólica e pressão arterial não houve diferença estatística entre os grupos 1,2,3 e 4. CONCLUSÕES: Os resultados mostram que a administração de Gd em ratos nefrectomizados resulta em dimuição da TFG, aumento da proteinúria associado a aumento da ferritina sérica, saturação de transferrina e diminuição da CTLF. Em ratos normais o Gd não mostrou ser nefrotóxico e o uso do NAC isoladamente no grupo 2 por curto período de tempo não demonstrou nenhum efeito, pois todos os parâmetros avaliados foram semelhantes ao grupo controle. Indução de stress oxidativo foi representado pelo aumento do TBARS nos ratos que receberam o Gd. O uso de NAC reverteu todas as alterações provocadas pelo Gd. Concluímos que o NAC pode ser usado como profilaxia da toxicidade associada ao Gd.INTRODUCTION: Gadolinium (Gd) is a rare class of lanthanide metal used as a contrast agent due to its paramagnetic properties. After its discovery, was considered a bit of contrast nephrotoxicity in patients with chronic kidney disease (CKD). Currently, there is evidence that Gd may present similar to iodine contrast media nephrotoxicity. The administration of Gadolinium in rats with CKD can lead to worsening renal function measured by inulin clearance and mobilization of iron body causing oxidative stress. OBJECTIVES: The aim of this study was to evaluate the effect of Gd on renal function, iron parameters and oxidative stress in rats with CKD and a possible effect of antioxidant N-Acetylcisteine (NAC). MATERIALS AND METHODS: Male Wistar rats underwent nephrectomy 5/6 (Nx) to induce CKD. Gadoterate meglumine, a Gadolinium based contrast ionic and macrocyclic was administrated intravenously at a dose of 1.5 mmol / kg BW of rats 21 days after nephrectomy. To evaluate the effect of Gd on renal function, inulin clearance studies were performed in 3 groups of animals 48 hours (hs) after application of Gd: a control group 1 - Nx (n =7), 2- Nx+NAC (n = 6); 3- Nx+Gd (n=8) e 4- Nx+Gd+NAC (n=5). The NAC was administrated in group 4, diluted with water 48 hs before and 48 hs after administration of gadolinium at a dose of 4800mg / l. Group 2 received NAC four days before clearance study. Gd was also administrated in rats with normal renal function, group normal (n = 8) at the same dose of nephrectomized rats with assessment of renal function and proteinuria. In addition to the glomerular filtration rate (GFR) were evaluated: 24 hours proteinuria (ptn), cage metabolic parameters, blood pressure (BP), serum iron (Fe), total capacity of iron binding (TIBC), transferrin saturation, serum ferritin and oxidative stress through measurement of thiobarbituric acid reactive species (TBARS). Data were submitted to ANOVA using the program Prism Graph with a significance level p <0.05 and standard error. RESULTS: Gd administration to group 3 results in a decrease of GFR compared with group 1 (p<0,01). There was a trend of increase ptn in group 3 compared to other groups. Normal rats treated with the same dose of Gd presented similar GFR and proteinuria when compared with normal controls. In group 3, there was a decrease in TIBC, elevation of ferritin serum levels, transferrin oversaturation and plasmatic TBARS elevation compared with group 1 (p<0,01), (p<0,05), (p<0,01) and (p<0,05) repectively. The treatment with NAC in group 4 reversed the decreased in GFR and proteinuria compared with group 3 (p<0,05) for both variables. Treatment with NAC in group 4 also reversed all alterations in iron parameters and oxidative stress described earlier with statistical significance (p<0,01), (p<0,05), (p<0,01) and (p<0,05) respectively. Group 2 received NAC for a short period of time had GFR, Ptn and kinetic parameters of iron similar to groups 1 and 4. With respect to metabolic cage data and blood pressure showed no statistical difference between groups 1,2,3 and 4.CONCLUSIONS: These results show that Gd administration to nephrectomized rats results in a decrease of GFR and increased proteinuria associated with increased serum ferritin and transferrin saturation with decreased TIBC. In normal rats, Gd was not nephrotoxic. These effects were not due to a possible effect of NAC on Nx, since all parameters measured in group 2 were not different from the group 1. There was induction of oxidative stress represented by the increase in TBARS in rats receiving gadolinium. The use of NAC reversed all these changes caused by Gd. We conclude that the NAC can be used as prophylaxis of toxicity associated with Gd
N-Acetylcysteine Protects Rats with Chronic Renal Failure from Gadolinium-Chelate Nephrotoxicity
The aim of this study was to evaluate the effect of Gd-chelate on renal function, iron parameters and oxidative stress in rats with CRF and a possible protective effect of the antioxidant N-Acetylcysteine (NAC). Male Wistar rats were submitted to 5/6 nephrectomy (Nx) to induced CRF. An ionic - cyclic Gd (Gadoterate Meglumine) was administrated (1.5 mM/KgBW, intravenously) 21 days after Nx. Clearance studies were performed in 4 groups of anesthetized animals 48 hours following Gd-chelate administration: 1 - Nx (n = 7); 2 - Nx+NAC (n = 6); 3 - Nx+Gd (n = 7); 4 - Nx+NAC+Gd (4.8 g/L in drinking water), initiated 2 days before Gd-chelate administration and maintained during 4 days (n = 6). This group was compared with a control. We measured glomerular filtration rate, GFR (inulin clearance, ml/min/kg BW), proteinuria (mg/24 hs), serum iron (mu g/dL); serum ferritin (ng/mL); transferrin saturation (%), TIBC (mu g/dL) and TBARS (nmles/ml). Normal rats treated with the same dose of Gd-chelate presented similar GFR and proteinuria when compared with normal controls, indicating that at this dose Gd-chelate is not nephrotoxic to normal rats. Gd-chelate administration to Nx-rats results in a decrease of GFR and increased proteinuria associated with a decrease in TIBC, elevation of ferritin serum levels, transferrin oversaturation and plasmatic TBARS compared with Nx-rats. The prophylactic treatment with NAC reversed the decrease in GFR and the increase in proteinuria and all alterations in iron parameters and TBARS induced by Gd-chelate. NAC administration to Nx rat did not modify the inulin clearance and iron kinetics, indicating that the ameliorating effect of NAC was specific to Gd-chelate. These results suggest that NAC can prevent Gd-chelate nephrotoxicity in patients with chronic renal failure
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