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4.
Harmful Algae ; 86: 84-95, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31358280

RESUMO

Microcystin is a cyanobacterial hepatotoxin of global concern. Understanding the environmental factors that cause high concentrations of microcystin is crucial to the development of lake management strategies that minimize harmful exposures. While the literature is replete with studies linking cyanobacterial production of microcystin to changes in various nutrients, abiotic stressors, grazers, and competitors, no single biotic or abiotic factor has been shown to be reliably predictive of microcystin concentrations in complex ecosystems. We performed random forest regression analyses with 16S and 18S rRNA gene sequencing data and environmental data to determine which putative ecological drivers best explained spatiotemporal variation in total microcystin and several individual congeners in a eutrophic freshwater reservoir. Model performance was best for predicting concentrations of the congener MC-LR, with ca. 88% of spatiotemporal variance explained. Most of the variance was associated with changes in the relative abundance of the cyanobacterial genus Microcystis. Follow-up RF regression analyses revealed that factors that were the most important in predicting MC-LR were also the most important in predicting Microcystis population dynamics. We discuss how these results relate to prevailing ecological hypotheses regarding the function of microcystin.


Assuntos
Cianobactérias , Microcystis , Ecossistema , Lagos , Microcistinas
5.
J Appl Microbiol ; 125(5): 1286-1295, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29972893

RESUMO

AIM: The effect of anacardic acid impregnation on catheter surfaces for the prevention of Staphylococcus aureus attachments and biofilm formations were evaluated. METHODS AND RESULTS: Silicon catheter tubes were impregnated using different concentrations of anacardic acids (0·002-0·25%). Anacardic acids are antibacterial phenolic lipids from cashew nut (Anacardium occidentale) shell oil. Anacardic acid-impregnated silicon catheters revealed no significant haemolytic activity and were cytocompatible against fibroblast cell line (L929). Sustained release of anacardic acids was observed for 4 days. Anacardic acid-impregnated silicon catheters efficiently inhibited S. aureus colonization and the biofilm formation on its surface. The in vivo antibiofilm activity of anacardic acid-impregnated catheters was tested in an intraperitoneal catheter-associated medaka fish infection model. Significant reduction in S. aureus colonization on anacardic acid-impregnated catheter tubes was observed. CONCLUSIONS: Our data suggest that anacardic acid-impregnated silicon catheters may help in preventing catheter-related staphylococcal infections. SIGNIFICANCE AND IMPACT OF THE STUDY: This study opens new directions for designing antimicrobial phytochemical-coated surfaces with ideal antibiofilm properties and could be of great interest for biomedical research scientists.


Assuntos
Ácidos Anacárdicos/farmacologia , Anacardium/química , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
6.
Allergy ; 73(9): 1871-1880, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29688579

RESUMO

BACKGROUND: Effective inhibition of plasma kallikrein may have significant benefits for patients with hereditary angioedema due to deficiency of C1 inhibitor (C1-INH-HAE) by reducing the frequency of angioedema attacks. Avoralstat is a small molecule inhibitor of plasma kallikrein. This study (OPuS-2) evaluated the efficacy and safety of prophylactic avoralstat 300 or 500 mg compared with placebo. METHODS: OPuS-2 was a Phase 3, multicenter, randomized, double-blind, placebo-controlled, parallel-group study. Subjects were administered avoralstat 300 mg, avoralstat 500 mg, or placebo orally 3 times per day for 12 weeks. The primary efficacy endpoint was the angioedema attack rate based on adjudicator-confirmed attacks. RESULTS: A total of 110 subjects were randomized and dosed. The least squares (LS) mean attack rates per week were 0.589, 0.675, and 0.593 for subjects receiving avoralstat 500 mg, avoralstat 300 mg, and placebo, respectively. Overall, 1 subject in each of the avoralstat groups and no subjects in the placebo group were attack-free during the 84-day treatment period. The LS mean duration of all confirmed attacks was 25.4, 29.4, and 31.4 hours for the avoralstat 500 mg, avoralstat 300 mg, and placebo groups, respectively. Using the Angioedema Quality of Life Questionnaire (AE-QoL), improved QoL was observed for the avoralstat 500 mg group compared with placebo. Avoralstat was generally safe and well tolerated. CONCLUSIONS: Although this study did not demonstrate efficacy of avoralstat in preventing angioedema attacks in C1-INH-HAE, it provided evidence of shortened angioedema episodes and improved QoL in the avoralstat 500 mg treatment group compared with placebo.


Assuntos
Angioedemas Hereditários/prevenção & controle , Inibidores Enzimáticos/uso terapêutico , Calicreína Plasmática/antagonistas & inibidores , Administração Oral , Adulto , Angioedemas Hereditários/diagnóstico , Angioedemas Hereditários/tratamento farmacológico , Progressão da Doença , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/efeitos adversos , Inibidores Enzimáticos/farmacocinética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Recidiva , Resultado do Tratamento
7.
Allergy ; 73(10): 2012-2023, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29574787

RESUMO

BACKGROUND: The epidemiology of multiple drug intolerance syndrome (MDIS) and multiple drug allergy syndrome (MDAS) is poorly characterized. We used electronic health record (EHR) data to describe prevalences of MDIS and MDAS and to examine associations with anxiety and depression. METHODS: Patients with ≥3 outpatient encounters at Partners HealthCare System from 2008 to 2015 were included. Patients with MDIS had intolerances to ≥3 drug classes, and patients with MDAS had hypersensitivities to ≥2 drug classes. Psychiatric conditions and comorbidities were defined from the EHR and used in multivariable logistic regression models to assess the relation between anxiety/depression and MDIS/MDAS. RESULTS: Of 746 888 patients, 47 634 (6.4%) had MDIS and 8615 (1.2%) had MDAS; 3171 (0.4%) had both. Anxiety (adjusted odds ratio [aOR] 1.72 [1.65, 1.80]), depression (aOR 1.46 [1.41, 1.52]), and both anxiety and depression (aOR 1.97 [1.86, 2.08]) were associated with increased odds of MDIS. Depression was associated with increased odds of MDAS (aOR 1.41 [1.28, 1.56]), but there were no clear associations with anxiety (aOR 1.13 [0.99, 1.30]) nor both depression and anxiety (aOR 1.13 [0.92, 1.38]). CONCLUSION: While 6% of patients had MDIS, only 1% had MDAS. MDIS was associated with both anxiety and depression; patients with both anxiety and depression had an almost twofold increased odds of MDIS. MDAS was associated with a 40% increased odds of depression, but there was no significant association with anxiety. Psychological assessments may be useful in the evaluation and treatment of patients with MDIS and MDAS; physiologic causes for MDAS warrant further investigation.


Assuntos
Ansiedade/epidemiologia , Comorbidade , Depressão/epidemiologia , Síndrome de Hipersensibilidade a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Adulto , Idoso , Registros Eletrônicos de Saúde , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos
8.
Hydrobiologia ; 818(1): 71-86, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31595089

RESUMO

DNA metabarcoding is a sophisticated molecular tool that can enhance biological surveys of freshwater plankton communities by providing broader taxonomic coverage and, for certain groups, higher taxonomic resolution compared to morphological methods. We conducted 18S rRNA gene metabarcoding analyses on 214 water samples collected over a four-month period from multiple sites within a freshwater reservoir. We detected 1,314 unique operational taxonomic units that included various metazoans, protists, chlorophytes, and fungi. Alpha diversity differed among sites, suggesting local habitat variation linked to differing species responses. Strong temporal variation was detected at both daily and monthly scales. Diversity and relative abundance patterns for several protist groups (including dinoflagellates, ciliates, and cryptophytes) differed from arthropods (e.g., cladocerans and copepods), a traditional focus of plankton surveys. This suggests that the protists respond to different environmental dimensions and may therefore provide additional information regarding ecosystem status. Comparison of the sequence-based population survey data to conventional-based data revealed similar trends for taxa that were ranked among the most abundant in both approaches, although some groups were missing in each data set. These results highlight the potential benefit of supplementing conventional biological survey approaches with metabarcoding to obtain a more comprehensive understanding of freshwater plankton community structure and dynamics.

9.
Phys Chem Chem Phys ; 19(4): 2990-2999, 2017 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-28079198

RESUMO

Preeclampsia, a pregnancy-specific disorder, shares typical pathophysiological features with protein misfolding disorders including Alzheimer's disease. Characteristic for preeclampsia is the involvement of multiple proteins of which fragments of SERPINA1 and ß-amyloid co-aggregate in urine and placenta of preeclamptic women. To explore the biophysical basis of this interaction, we investigated the multidimensional efficacy of the FVFLM sequence in SERPINA1, as a model inhibitory agent of ß-amyloid aggregation. After studying the oligomerization of FVFLM peptides using all-atom molecular dynamics simulations with the GROMOS43a1 force field and explicit water, we report that FVFLM can aggregate and its aggregation is spontaneous with a remarkably faster rate than that recorded for KLVFF (aggregation "hot-spot" from ß-amyloid). The fast kinetics of FVFLM aggregation was found to be driven primarily by core-like aromatic interactions originating from the anti-parallel orientation of complementarily uncharged strands. The conspicuously stable aggregation mechanism observed for FVFLM peptides is found not to conform to the popular 'dock-lock' scheme. We also found high propensity of FVFLM for KLVFF binding. When present, FVFLM disrupts the ß-amyloid aggregation pathway and we propose that FVFLM-like peptides might be used to prevent the assembly of full-length Aß or other pro-amyloidogenic peptides into amyloid fibrils.


Assuntos
Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/metabolismo , Modelos Moleculares , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Peptídeos/química , Peptídeos/metabolismo , Cinética , Simulação de Dinâmica Molecular , Polimerização , Ligação Proteica
10.
Clin Exp Immunol ; 177(2): 544-53, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24749847

RESUMO

Hereditary angioedema (HAE) is characterized by potentially life-threatening recurrent episodes of oedema. The open-label extension (OLE) phase of the For Angioedema Subcutaneous Treatment (FAST)-1 trial (NCT00097695) evaluated the efficacy and safety of repeated icatibant exposure in adults with multiple HAE attacks. Following completion of the randomized, controlled phase, patients could receive open-label icatibant (30 mg subcutaneously) for subsequent attacks. The primary end-point was time to onset of primary symptom relief, as assessed by visual analogue scale (VAS). Descriptive statistics were reported for cutaneous/abdominal attacks 1-10 treated in the OLE phase and individual laryngeal attacks. Post-hoc analyses were conducted in patients with ≥ 5 attacks across the controlled and OLE phases. Safety was evaluated throughout. During the OLE phase, 72 patients received icatibant for 340 attacks. For cutaneous/abdominal attacks 1-10, the median time to onset of primary symptom relief was 1·0-2·0 h. For laryngeal attacks 1-12, patient-assessed median time to initial symptom improvement was 0·3-1·2 h. Post-hoc analyses showed the time to onset of symptom relief based on composite VAS was consistent across repeated treatments with icatibant. One injection of icatibant was sufficient to treat 88·2% of attacks; rescue medication was required in 5·3% of attacks. No icatibant-related serious adverse events were reported. Icatibant provided consistent efficacy and was well tolerated for repeated treatment of HAE attacks.


Assuntos
Angioedemas Hereditários/tratamento farmacológico , Bradicinina/análogos & derivados , Adulto , Angioedemas Hereditários/diagnóstico , Bradicinina/administração & dosagem , Bradicinina/efeitos adversos , Bradicinina/uso terapêutico , Antagonistas dos Receptores da Bradicinina , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Retratamento , Resultado do Tratamento , Adulto Jovem
11.
Allergy ; 69(5): 602-16, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24673465

RESUMO

Angioedema is defined as localized and self-limiting edema of the subcutaneous and submucosal tissue, due to a temporary increase in vascular permeability caused by the release of vasoactive mediator(s). When angioedema recurs without significant wheals, the patient should be diagnosed to have angioedema as a distinct disease. In the absence of accepted classification, different types of angioedema are not uniquely identified. For this reason, the European Academy of Allergy and Clinical Immunology gave its patronage to a consensus conference aimed at classifying angioedema. Four types of acquired and three types of hereditary angioedema were identified as separate forms from the analysis of the literature and were presented in detail at the meeting. Here, we summarize the analysis of the data and the resulting classification of angioedema.


Assuntos
Angioedema/diagnóstico , Angioedema/tratamento farmacológico , Angioedema/etiologia , Humanos
13.
J Membr Sci Technol ; 4(1)2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26207187

RESUMO

The prognosis of patients with Glioblastoma Multiforme (GBM), the most malignant adult glial brain tumor, remains poor in spite of advances in treatment procedures, including surgical resection, irradiation and chemotherapy. Genetic heterogeneity of GBM warrants extensive studies to gain a thorough understanding of the biology of this tumor. While there have been several studies of global transcript profiling of glioma with the identification of gene signatures for diagnosis and disease management, translation into clinics is yet to happen. In the present study, we report a novel proteomic approach by using two-dimensional difference gel electrophoresis (2D-DIGE) followed by spot picking and analysis of proteins/peptides by Mass Spectrometry. We report Glucose Regulated Protein 78 (GRP78) as a differentially expressed protein in the GBM cell line compared to human normal Astrocyte cells. In addition to proteomic studies, we performed microarray analysis which further confirmed up regulation of GRP78 in GBM cells compared to human normal Astrocyte cells. GRP78 has long been recognized as a molecular chaperone in the endoplasmic reticulum (ER) and can be induced by the ER stress response. Besides its location in the ER, GRP78 has been found in cell plasma membrane, cytoplasm, mitochondria, nucleus and other cellular secretions. GRP78 is implicated in tumor cell proliferation, apoptosis resistance, immune escape, metastasis and angiogenesis, and its elevated expression usually correlates with a variety of tumor micro environmental stresses, including hypoxia, glucose deprivation, lactic acidosis and inflammatory response. GRP78 protein acts as a centrally located sensor of stress, which senses and facilitates the adaptation to the tumor microenvironment. Our findings showed differential expression of this gene in brain cancer GBM and thus confirm similarities in findings in existing transcriptional and translational studies. Thus, these findings could be of further importance for diagnostic, therapeutic and prognostic approaches for dealing with this highly malignant cancer.

14.
J Health Econ ; 31(1): 62-71, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22317960

RESUMO

Using a discrete choice experiment, this paper estimates the willingness to pay for biofortified orange maize in rural Zambia. The study design has five treatment arms, which enable an analysis of the impact of nutrition information, comparing the use of simulated radio versus community leaders in transmitting the nutrition message, on willingness to pay, and to account for possible novelty effects in the magnitude of premiums or discounts. The estimation strategy also takes into account lexicographic preferences of a subset of our respondents. The results suggest that (a) orange maize is not confused with yellow maize, and has the potential to compete with white maize in the absence of a nutrition campaign, (b) there is a premium for orange maize with nutrition information, and (c) different modes of nutritional message dissemination have the same impact on consumer acceptance.


Assuntos
Comportamento de Escolha , Preferências Alimentares/psicologia , Alimentos Fortificados/economia , População Rural , Zea mays/economia , Adulto , Feminino , Promoção da Saúde , Humanos , Disseminação de Informação , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Zâmbia , Zea mays/química
15.
Bioorg Med Chem Lett ; 21(18): 5328-30, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21821414

RESUMO

A practical synthesis of polyhydroxy- and regiospecifically methylated flavone-3-ols which are components of commercial 'seabuckthorn flavone' has been achieved by modified Algar-Flynn-Oyamada method. Antioxidant activities of seabuckthorn extracts, isolated products and a number of flavone-3-ols have been determined. Structure-activity relationships have been discussed. Amongst the compounds tested, gallic acid, which is also present in seabuckthorn, was found to be the most effective antioxidant and radioprotectant.


Assuntos
Antioxidantes/química , Antioxidantes/síntese química , Flavonas/química , Flavonas/síntese química , Oxigênio/química , Antioxidantes/isolamento & purificação , Técnicas de Química Sintética , Flavonas/isolamento & purificação , Estrutura Molecular , Estereoisomerismo , Relação Estrutura-Atividade
18.
J Environ Biol ; 29(6): 951-7, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19297999

RESUMO

Ageratochromes or precocenes are known for their insect growth regulating (IGR) activity. The present investigation was taken up with an objective to look for the lead structure in these compounds which can be elaborated synthetically to obtain useful growth regulators for practical purposes. With this in mind, some variants of precocenes were synthesized in the laboratory and tested for their toxicity and growth regulating activity using red cotton bug Dysdercus koenigii as the test insect. Most of the precocenoids showed toxicity of various degree and metamorphic derangements to different extents. Adults emerging from treated nymphs could not complete the normal life span. Among the compounds tested 8-acetyl-7-hydroxy-5-methoxy-dimethylchromene (alloevodinol) was more toxic and also showed developmental defects at very low dose such as 0.5 mg l(-1)/nymph. Precocene II (6, 7-dimethoxy-2, 2-dimethylchromene) was used as the standard compound. It was the least toxic and showed effects at 30 mg l(-1)/nymph.


Assuntos
Benzopiranos/síntese química , Heterópteros/efeitos dos fármacos , Controle de Insetos , Hormônios Juvenis/síntese química , Animais , Benzopiranos/química , Benzopiranos/toxicidade , Heterópteros/crescimento & desenvolvimento , Hormônios Juvenis/química , Hormônios Juvenis/toxicidade , Dose Letal Mediana , Ninfa/efeitos dos fármacos , Ninfa/crescimento & desenvolvimento
19.
Med J Armed Forces India ; 64(2): 131-5, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27408114

RESUMO

BACKGROUND: The Amplatzer perimembranous ventricular septal occluder is an innovative device for percutaneous closure of perimembranous ventricular septal defects (PMVSD). In appropriately selected cases this procedure is safe and effective. METHODS: Fourteen patients with the mean age 10.53 years (range 18 months to 55 years) and mean body weight 20.64 kg (range 6 to 52 kg) underwent PMVSD closure. RESULT: The PMVSD mean diameter was 5.28 mm (range from 4 to 9 mm). Implantation was successful in 92% of the cases and all patients had complete occlusion of the shunt within three months. CONCLUSION: Device orientation was excellent in all cases. Device-related aortic insufficiency, tricuspid insufficiency or left ventricular dysfunction was not observed. One patient had embolisation of the device and another had complete heart block which required a permanent pacemaker implantation. The excellent short term results need to be confirmed over long-term follow-up.

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