253 research outputs found

    Quantification of chloroquine by LC-MS and the macular degeneration disease

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    Trabalho Final de Mestrado Integrado, CiĂȘncias FarmacĂȘuticas, Universidade de Lisboa, Faculdade de FarmĂĄcia, 2017Age-related macular degeneration is a visual disease that involves a progressive loss of central vision which its consequences are dramatic for the patient’s quality of life. Age is a major risk factor for macular degeneration. Other risk factors include, ethnicity, genetics, smoking and drugs. Chloroquine appears to be the most toxic drug to the retina, which might be explained by the extensive accumulation and very long retention of chloroquine bound to melanin. Chloroquine is used for malarial prevention and treatment, as well to various inflammatory diseases such as rheumatoid arthritis and lupus erythematosus. Chloroquine toxicity in age-related macular degeneration is of serious ophthalmologic concern because it is not treatable. Nonetheless, it has been demonstrated that central vision can be preserved if damage is recognized before there are changes in the retinal pigment epithelium. With proper screening, bull’s-eye retinopathy, no longer should be seen. The focus of this study is the development of a precise and sensible method of quantification of chloroquine, by using liquid chromatography–mass spectrometry, to determine the amount of chloroquine that binds to melanin when using a tissue sample and to relate the melanin-chloroquine binding to macular degeneration or age-related macular degeneration, from the premise that the extensive binding of chloroquine to the melanin of the eye contributes to a quicker evolution of the macular degeneration disease. A method of melanosome extraction and melanin-cloroquine binding was accomplished. It was also developed a liquid chromatography–mass spectrometry method. HPLC was done in an Agilent 1260 Infinity instrument with a Poroshell 120 SB-C18 column (2.1 x 50 mm, 2.7 ”m). Mass spectrometry used an Agilent 6495 Triple Quadrupole Mass Spectrometer. The results showed the suitability of the method, which was improved with a stability study of chloroquine, included on this work. The results showed that more than 50% of the chloroquine binds to melanin, independently of the concentration of the melanin used. In the future, a more sensible method should be developed with other columns of HPLC. The present work joins the studies that associate the relation between chloroquine therapeutic and its influence on retinopathy, and therefore on AMD, making its consequences appear sooner or greater.A degenerescĂȘncia macular da idade (DMI) Ă© uma doença oftĂĄlmica que envolve a perda progressiva de visĂŁo central e cujas consequĂȘncias sĂŁo dramĂĄticas para a qualidade de vida do doente. A idade Ă© um importante fator de risco para a degenerescĂȘncia macular. Outros fatores de risco incluem: etnia, genĂ©tica, tabagismo e medicamentos. A cloroquina parece ser o fĂĄrmaco mais tĂłxico para a retina, dada a sua extensa acumulação e retenção longa quando ligada Ă  melanina. A cloroquina Ă© utilizada na prevenção e tratamento da malĂĄria, sendo tambĂ©m utilizada na terapĂȘutica de doenças inflamatĂłrias, como a artrite reumatoide e o lĂșpus eritematoso. A toxicidade da cloroquina na degenerescĂȘncia macular da idade Ă© uma preocupação oftalmolĂłgica sĂ©ria dada a ausĂȘncia de tratamento. No entanto, demonstrou-se que o centro da visĂŁo pode ser preservado se o dano for reconhecido antes de ocorrerem alteraçÔes no epitĂ©lio do pigmento da retina. Com rastreio apropriado, a retinopatia do “olho de boi” deixarĂĄ de se expressar. Este trabalho tem como objetivo o desenvolvimento de um mĂ©todo preciso e sensĂ­vel de quantificação de cloroquina, usando cromatografia lĂ­quida-espectrometria de massa, para determinar a quantidade de cloroquina que se liga Ă  melanina, usando uma amostra de tecido, e relacionar a associação da cloroquina Ă  melanina com a degenerescĂȘncia macular ou degenerescĂȘncia macular da idade. Foi realizado um mĂ©todo de extração melanossomal e de ligação melanina-cloroquina. Foi, igualmente, desenvolvido um mĂ©todo de LC-MS. O HPLC foi executado num aparelho Agilent 1260 Infinity com uma coluna Poroshell 120 SB-C18 (2,1 x 50 mm, 2,7 ÎŒm). A espectrometria de massa foi realizada com um espectrĂłmetro Agilent 6495 Triple Quadrupole. Os resultados mostraram a adequação do mĂ©todo, sendo que este foi melhorado com um estudo de estabilidade da cloroquina, incluĂ­do neste trabalho. Os resultados mostraram que mais de 50% da cloroquina se liga Ă  melanina, independentemente da concentração de melanina utilizada. No futuro, deverĂĄ ser desenvolvido um mĂ©todo mais sensĂ­vel com o uso de outras colunas de HPLC. O presente trabalho junta-se aos estudos que associam a relação entre a terapĂȘutica de cloroquina e sua influĂȘncia na retinopatia e, portanto, na AMD, fazendo com que suas consequĂȘncias aparecem mais precocemente

    The institutions of archaic post-modernity and their organizational and managerial consequences: The case of Portugal

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    The long march of modernization of the Western societies tends to be presented as following a regular sequence: societies and institutions were pre-modern, and then they were modernized, eventually becoming post-modern. Such teleology may provide an incomplete or distorted narrative of societal evolution in many parts of the world, even in the ‘post-modern heartland’ of Western Europe, with Portugal being a case in point. The concept of archaic post-modernity has been developed by a philosopher, JosĂ© Gil, to show how Portuguese institutions and organizations combine elements of pre-modernity and post-modernity. The notion of an archaic post-modernity is advanced in order to provide an alternative account of the modernization process, which enriches discussion of the varieties of capitalism. Differences in historical experiences create singularities that may be considered in the analysis of culture, management and organization

    Large-scale screening of unknown varieties in a grapevine intra-varietal variability collection

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    Since the last decade of the last century, it is known that many old grapevine varieties are descendants of other varieties through natural crossing. Portugal has an important program for the conservation of representative samples of intra-varietal variability of all autochthonous varieties, managed by the Portuguese Association for Grapevine Diversity (PORVID), which makes looking for genotypes with dubious identification an important activity from a perspective of its valorisation. This communication presents the results of the molecular analysis of 5,000 samples (accessions) from the PORVID’s collection, using nine microsatellite loci currently recommended by the International Organization of Vine and Wine (OIV) for genetic grapevine identification. The results obtained confirmed the molecular identity of 4,220 samples corresponding to 214 varieties present in the official list of Portuguese varieties. In 780 samples, 95 profiles with a plural number of accessions revealed not to be listed in the Vitis International Variety Catalogue (VIVC) database, corresponding to possible varieties either descendent from natural crossing from at least one known parental variety, or from undetermined origin. Furthermore, the need for a comprehensive strategy aimed at uncovering other hidden varieties is discussed to prevent their imminent loss, deepen understanding of their origin, and add economic value and sustainability to the vine and wine sector

    Pervasive gaps in Amazonian ecological research

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    Pervasive gaps in Amazonian ecological research

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    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

    Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

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    Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

    Canagliflozin and renal outcomes in type 2 diabetes and nephropathy

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    BACKGROUND Type 2 diabetes mellitus is the leading cause of kidney failure worldwide, but few effective long-term treatments are available. In cardiovascular trials of inhibitors of sodium–glucose cotransporter 2 (SGLT2), exploratory results have suggested that such drugs may improve renal outcomes in patients with type 2 diabetes. METHODS In this double-blind, randomized trial, we assigned patients with type 2 diabetes and albuminuric chronic kidney disease to receive canagliflozin, an oral SGLT2 inhibitor, at a dose of 100 mg daily or placebo. All the patients had an estimated glomerular filtration rate (GFR) of 30 to <90 ml per minute per 1.73 m2 of body-surface area and albuminuria (ratio of albumin [mg] to creatinine [g], >300 to 5000) and were treated with renin–angiotensin system blockade. The primary outcome was a composite of end-stage kidney disease (dialysis, transplantation, or a sustained estimated GFR of <15 ml per minute per 1.73 m2), a doubling of the serum creatinine level, or death from renal or cardiovascular causes. Prespecified secondary outcomes were tested hierarchically. RESULTS The trial was stopped early after a planned interim analysis on the recommendation of the data and safety monitoring committee. At that time, 4401 patients had undergone randomization, with a median follow-up of 2.62 years. The relative risk of the primary outcome was 30% lower in the canagliflozin group than in the placebo group, with event rates of 43.2 and 61.2 per 1000 patient-years, respectively (hazard ratio, 0.70; 95% confidence interval [CI], 0.59 to 0.82; P=0.00001). The relative risk of the renal-specific composite of end-stage kidney disease, a doubling of the creatinine level, or death from renal causes was lower by 34% (hazard ratio, 0.66; 95% CI, 0.53 to 0.81; P<0.001), and the relative risk of end-stage kidney disease was lower by 32% (hazard ratio, 0.68; 95% CI, 0.54 to 0.86; P=0.002). The canagliflozin group also had a lower risk of cardiovascular death, myocardial infarction, or stroke (hazard ratio, 0.80; 95% CI, 0.67 to 0.95; P=0.01) and hospitalization for heart failure (hazard ratio, 0.61; 95% CI, 0.47 to 0.80; P<0.001). There were no significant differences in rates of amputation or fracture. CONCLUSIONS In patients with type 2 diabetes and kidney disease, the risk of kidney failure and cardiovascular events was lower in the canagliflozin group than in the placebo group at a median follow-up of 2.62 years

    The impact of surgical delay on resectability of colorectal cancer: An international prospective cohort study

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    AIM: The SARS-CoV-2 pandemic has provided a unique opportunity to explore the impact of surgical delays on cancer resectability. This study aimed to compare resectability for colorectal cancer patients undergoing delayed versus non-delayed surgery. METHODS: This was an international prospective cohort study of consecutive colorectal cancer patients with a decision for curative surgery (January-April 2020). Surgical delay was defined as an operation taking place more than 4 weeks after treatment decision, in a patient who did not receive neoadjuvant therapy. A subgroup analysis explored the effects of delay in elective patients only. The impact of longer delays was explored in a sensitivity analysis. The primary outcome was complete resection, defined as curative resection with an R0 margin. RESULTS: Overall, 5453 patients from 304 hospitals in 47 countries were included, of whom 6.6% (358/5453) did not receive their planned operation. Of the 4304 operated patients without neoadjuvant therapy, 40.5% (1744/4304) were delayed beyond 4 weeks. Delayed patients were more likely to be older, men, more comorbid, have higher body mass index and have rectal cancer and early stage disease. Delayed patients had higher unadjusted rates of complete resection (93.7% vs. 91.9%, P = 0.032) and lower rates of emergency surgery (4.5% vs. 22.5%, P < 0.001). After adjustment, delay was not associated with a lower rate of complete resection (OR 1.18, 95% CI 0.90-1.55, P = 0.224), which was consistent in elective patients only (OR 0.94, 95% CI 0.69-1.27, P = 0.672). Longer delays were not associated with poorer outcomes. CONCLUSION: One in 15 colorectal cancer patients did not receive their planned operation during the first wave of COVID-19. Surgical delay did not appear to compromise resectability, raising the hypothesis that any reduction in long-term survival attributable to delays is likely to be due to micro-metastatic disease

    Updated cardiovascular prevention guideline of the Brazilian Society of Cardiology: 2019

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    Sem informação113478788

    Impact of common cardio-metabolic risk factors on fatal and non-fatal cardiovascular disease in Latin America and the Caribbean: an individual-level pooled analysis of 31 cohort studies

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    Background: Estimates of the burden of cardio-metabolic risk factors in Latin America and the Caribbean (LAC) rely on relative risks (RRs) from non-LAC countries. Whether these RRs apply to LAC remains un- known. Methods: We pooled LAC cohorts. We estimated RRs per unit of exposure to body mass index (BMI), systolic blood pressure (SBP), fasting plasma glucose (FPG), total cholesterol (TC) and non-HDL cholesterol on fatal (31 cohorts, n = 168,287) and non-fatal (13 cohorts, n = 27,554) cardiovascular diseases, adjusting for regression dilution bias. We used these RRs and national data on mean risk factor levels to estimate the number of cardiovascular deaths attributable to non-optimal levels of each risk factor. Results: Our RRs for SBP, FPG and TC were like those observed in cohorts conducted in high-income countries; however, for BMI, our RRs were consistently smaller in people below 75 years of age. Across risk factors, we observed smaller RRs among older ages. Non-optimal SBP was responsible for the largest number of attributable cardiovascular deaths ranging from 38 per 10 0,0 0 0 women and 54 men in Peru, to 261 (Dominica, women) and 282 (Guyana, men). For non-HDL cholesterol, the lowest attributable rate was for women in Peru (21) and men in Guatemala (25), and the largest in men (158) and women (142) from Guyana. Interpretation: RRs for BMI from studies conducted in high-income countries may overestimate disease burden metrics in LAC; conversely, RRs for SBP, FPG and TC from LAC cohorts are similar to those esti- mated from cohorts in high-income countries
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