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1.
Heliyon ; 10(3): e24670, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38314272

RESUMO

Cancer represents a significant global health and economic burden due to its high mortality rates. While effective in some instances, traditional chemotherapy often falls short of entirely eradicating various types of cancer. It can cause severe side effects due to harm to healthy cells. Two therapeutic approaches have risen to the forefront to address these limitations: metronomic chemotherapy (MCT) and drug repurposing. Metronomic chemotherapy is an innovative approach that breaks from traditional models. It involves the administration of chemotherapeutic regimens at lower doses, without long drug-free intervals that have previously been a hallmark of such treatments. This method offers a significant reduction in side effects and improved disease management. Simultaneously, drug repurposing has gained considerable attraction in cancer treatment. This approach involves utilizing existing drugs, initially developed for other therapeutic purposes, as potential cancer treatments. The application of known drugs in a new context accelerates the timeline from laboratory to patient due to pre-existing safety and dosage data. The intersection of these two strategies gives rise to a novel therapeutic approach named 'Metronomics.' This approach encapsulates the benefits of both MCT and drug repurposing, leading to reduced toxicity, potential for oral administration, improved patient quality of life, accelerated clinical implementation, and enhanced affordability. Numerous clinical studies have endorsed the efficacy of metronomic chemotherapy with tolerable side effects, underlining the potential of Metronomics in better cancer management, particularly in low- and middle-income countries. This review underscores the benefits and applications of metronomic chemotherapy and drug repurposing, specifically in the context of breast cancer, showcasing the promising results of pre-clinical and clinical studies. However, we acknowledge the necessity of additional clinical investigations to definitively establish the role of metronomic chemotherapy in conjunction with other treatments in comprehensive cancer management.

2.
Langmuir ; 39(23): 8224-8233, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37270702

RESUMO

Herein, a versatile FeCo2S4/Co3O4 heterostructure consisting of zeolitic imidazolate framework ZIF-derived Co3O4 and FeCo-layered double hydroxide-derived Fe-doped Co sulfide is employed for the all-important alkaline full water splitting process. The heterostructure is prepared by combining pyrolysis and hydrothermal/solvothermal processes. The synthesized heterostructure possesses an electrocatalytically rich interface and renders excellent bifunctional catalytic performance. An overpotential of 139 mV for a standard cathodic current of 10 mA cm-2 with a low Tafel slope of 81 mV dec-1 is recorded for the hydrogen evolution reaction. An overpotential of 210 mV is observed for an anodic current of 20 mA cm-2 with a low Tafel slope of 75 mV dec-1 recorded for the oxygen evolution reaction. The full-symmetric two-electrode cell was capable of generating a current density of 10 mA cm-2 at a cell potential of 1.53 V and a low onset potential of 1.49 V. The symmetric cell architecture exhibits remarkable stability, as a negligible potential increase is observed for continuous water splitting over a 10 h period. With the reported performance, the heterostructure compares well with most of the excellent reported catalysts for alkaline bifunctional catalysts.

3.
Biol Rev Camb Philos Soc ; 97(5): 1823-1843, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35580905

RESUMO

Convergence is the phenomenon whereby similar phenotypes evolve independently in different lineages. One example is resistance to toxins in animals. Toxins have evolved many times throughout the tree of life. They disrupt molecular and physiological pathways in target species, thereby incapacitating prey or deterring a predator. In response, molecular resistance has evolved in many species exposed to toxins to counteract their harmful effects. Here, we review current knowledge on the convergence of toxin resistance using examples from a wide range of toxin families. We explore the evolutionary processes and molecular adaptations driving toxin resistance. However, resistance adaptations may carry a fitness cost if they disrupt the normal physiology of the resistant animal. Therefore, there is a trade-off between maintaining a functional molecular target and reducing toxin susceptibility. There are relatively few solutions that satisfy this trade-off. As a result, we see a small set of molecular adaptations appearing repeatedly in diverse animal lineages, a phenomenon that is consistent with models of deterministic evolution. Convergence may also explain what has been called 'autoresistance'. This is often thought to have evolved for self-protection, but we argue instead that it may be a consequence of poisonous animals feeding on toxic prey. Toxin resistance provides a unique and compelling model system for studying the interplay between trophic interactions, selection pressures and the molecular mechanisms underlying evolutionary novelties.


Assuntos
Adaptação Fisiológica , Evolução Biológica , Adaptação Fisiológica/genética , Animais , Fenótipo
4.
PLoS One ; 17(4): e0246555, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35482717

RESUMO

Raptors are highly sensitive to environmental and human-induced changes. In addition, several species of raptors exist in considerably small numbers. It is thus critical to conserve raptors and their habitats across relatively larger landscapes. We examined the diurnal raptor assemblages and seasonality in a subtropical habitat in India's northwestern Himalayas. Quantitative data on diurnal birds of prey and their habitat features across six distinct habitat types were collected from 33 sample sites. We observed 3,434 individuals of 28 diurnal raptors belonging to two orders and three families during a two-year survey from December 2016 to November 2018. A significant variation in bird species richness and abundance was found across habitats and seasons, with farmlands and winters being the most diverse and speciose. The generalized linear model, used to determine raptor community responses, indicated that elevation and proximity to dumping sites significantly affected the raptor abundance. The non-metric multidimensional scaling (NMDS) revealed significant differences in raptor assemblages across the habitat types. The study concluded that raptors' persistence is largely determined by their preference for favourable feeding, roosting, and nesting opportunities. The presence of protected and habitat-exclusive species validates the high conservation importance of these ecosystems, particularly the forest patches and farmlands, necessitating robust conservation and management measures in this part of northwestern Himalaya.


Assuntos
Ecossistema , Aves Predatórias , Animais , Biodiversidade , Aves/fisiologia , Florestas , Humanos , Índia
5.
Cureus ; 13(11): e19310, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34900485

RESUMO

Background and aims Opioid dependence is a chronic, relapsing substance use disorder with a multifactorial etiology, including a genetic component. Serotonin pathway gene polymorphisms have been an important focus of research for psychiatric disorders, including substance use disorders. This study aimed to identify the association of serotonin pathway gene polymorphisms with self-harm, depressive symptoms, impulsiveness, and aggression in patients with opioid dependence. Method The study group comprised 366 subjects with opioid dependence and 200 healthy volunteers. Patients were assessed for a history of self-harm, depressive symptoms, impulsiveness, and aggression using standard tools. Genomic DNA was used for genotyping of four polymorphisms - 5-HTTLPR, STin2 VNTR, TPH1 A218C, and TPH2 G703T. Results The short allele of 5-HTTLPR polymorphism showed a significant difference between cases (59.8%) and controls (40.1%) (p=0.001) and revealed an association with age at opioid dependence (p=0.033). There was a borderline significance of the short allele of 5-HTTLPR with the duration of opioid use (p=0.061) and non-plan impulsivity (p=0.076), suggesting a role of 5-HTTLPR in the susceptibility of opioid dependence. The other markers did not differ between cases and controls. However, the STin2A polymorphism revealed a significant association with anger scores, which may indicate its role in aggressive behavior. Conclusions The present study, the first of its kind, suggests an association of 5-HTTLPR polymorphism with opioid dependence and STin2A polymorphism with aggressive behavior among opioid-dependence patients, signifying the role of these markers in our patient population.

6.
J Parasit Dis ; 45(4): 1084-1089, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34789993

RESUMO

The aim is to study the morphological and ecological features of some nematode species of the genus Rhabdochona parasites of marinka fish in the Fergana Valley, Uzbekistan. Rhabdochona gnedini, Rhabdochona denudata and Rhabdochona hellichi turkestanica were detected as 5.3%, 7.9% and 3.7%, respectively. According to the Authors' knowledge, Rh. hellichi turkestanica was recorded in Uzbekistan and Central Asian republics for the first time. Rhabdochona spp. were only detected in the intestine of marinkas lived in the mountain rivers Rezaksay, Chodaksay and small tributaries of the Syrdarya river in western Fergana. The prevalence of Rhabdochona spp. in the marinka can be associated with a wide range of nutrition in the mountain rivers and small tributaries of the Syrdarya river, where it could eat large numbers of mayfly and caddis larvae that act as intermediate hosts of rhabdochona.

7.
Ann Indian Acad Neurol ; 24(4): 552-558, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34728950

RESUMO

CONTEXT: Autoantibodies have a role in the diagnosis and prognosis in Autoimmune Inflammatory Myositis (AIM). AIMS: The aim of this work was to study the prevalence and clinical correlation of myositis specific and associated antibodies (MSA and MAA) in AIM. SETTING AND DESIGN: This was a cross-sectional observational study. METHODS AND MATERIALS: Consecutive AIM patents were divided into groups as dermatomyositis (DM), polymyositis (PM), CTD-associated myositis (CTD-M), cancer-associated myositis (CAM) and juvenile myositis (JM). Their data along with serum samples were collected after obtaining informed consent. Sera was analyzed for IgG antibodies against Jo-1, PL-7, PL-12, EJ, SRP, Mi-2, MDA-5, TIF1γ, SAE1, SAE2, NXP2 and SSA/R052kD using the microELISA technique. The institutional ethics committee approved the study. STATISTICAL ANALYSIS: SPSS software (version 24.0) was used. P value < 0.05 was considered statistically significant. RESULTS: There were 48 patients (DM = 19, PM = 19, CTD-M = 5, CAM = 2, JM = 3) included. MSA were positive in 37.5% patients. Antibodies against Mi-2 were present in 6 (12.5%), Jo-1 in 5 (10.4%), 2 (4.1%) each had PL-7 and SRP antibodies. One patient (2%) each had MDA-5, NXP2 and TIf1g antibodies. Jo-1 antibody was associated with mechanic's hands and ILD. There was a significant association of rash in the Mi-2 group with none of the patients having ILD. Malignancy screening was negative in NXP2 and TIF1g antibody-positive patients. Ro52 was the most common MAA (33.3%) and was associated with mechanic's hand. CONCLUSION: MSA was present in almost 40% of the cohort. Anti Jo-1 antibody was associated with mechanic's hands and ILD. None of the Mi-2 patients had ILD, which may point to a protective role of this antibody for ILD. The association of newer antibodies in Indian patients needs to be further studied in larger cohorts.

8.
Toxins (Basel) ; 12(10)2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33023159

RESUMO

Venomous snakes are important subjects of study in evolution, ecology, and biomedicine. Many venomous snakes have alpha-neurotoxins (α-neurotoxins) in their venom. These toxins bind the alpha-1 nicotinic acetylcholine receptor (nAChR) at the neuromuscular junction, causing paralysis and asphyxia. Several venomous snakes and their predators have evolved resistance to α-neurotoxins. The resistance is conferred by steric hindrance from N-glycosylated asparagines at amino acids 187 or 189, by an arginine at position 187 that has been hypothesized to either electrostatically repulse positively charged neurotoxins or sterically interfere with α-neurotoxin binding, or proline replacements at positions 194 or 197 of the nAChR ligand-binding domain to inhibit α-neurotoxin binding through structural changes in the receptor. Here, we analyzed this domain in 148 vertebrate species, and assessed its amino acid sequences for resistance-associated mutations. Of these sequences, 89 were sequenced de novo. We find widespread convergent evolution of the N-glycosylation form of resistance in several taxa including venomous snakes and their lizard prey, but not in the snake-eating birds studied. We also document new lineages with the arginine form of inhibition. Using an in vivo assay in four species, we provide further evidence that N-glycosylation mutations reduce the toxicity of cobra venom. The nAChR is of crucial importance for normal neuromuscular function and is highly conserved throughout the vertebrates as a result. Our research shows that the evolution of α-neurotoxins in snakes may well have prompted arms races and mutations to this ancient receptor across a wide range of sympatric vertebrates. These findings underscore the inter-connectedness of the biosphere and the ripple effects that one adaption can have across global ecosystems.


Assuntos
Resistência a Medicamentos , Evolução Molecular , Junção Neuromuscular/efeitos dos fármacos , Neurotoxinas/toxicidade , Antagonistas Nicotínicos/toxicidade , Receptores Nicotínicos/efeitos dos fármacos , Mordeduras de Serpentes/metabolismo , Venenos de Serpentes/toxicidade , Serpentes/metabolismo , Animais , Sítios de Ligação , Resistência a Medicamentos/genética , Glicosilação , Mutação , Junção Neuromuscular/metabolismo , Junção Neuromuscular/fisiopatologia , Neurotoxinas/metabolismo , Antagonistas Nicotínicos/metabolismo , Filogenia , Ligação Proteica , Receptores Nicotínicos/genética , Receptores Nicotínicos/metabolismo , Mordeduras de Serpentes/fisiopatologia , Venenos de Serpentes/metabolismo , Especificidade da Espécie
9.
Cardiovasc Intervent Radiol ; 43(12): 1756-1769, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32588136

RESUMO

Open surgical repair of the aortic arch for degenerative aortic disease in an unfit patient is associated with significant morbidity and mortality. Endoluminal techniques have advanced over the last decade. Contemporary endovascular options including a hybrid approach (supra-aortic debranching and aortic stent graft), inner branched endograft, chimney stents, and scallop or fenestrated endografts are being used frequently as an alternative to open surgical arch repair. Understanding of the available endoluminal technology along with careful planning and effective teamwork is required to minimise complications associated with the endoluminal techniques, particularly neurological ones. Custom made techniques are superior to chimney or parallel technology in terms of their complications and durability. Integration of the protective devices such as embolic protection filters into stent design may reduce the risk of poor neurological sequelae. Long-term data are needed to assess the durability of these devices.


Assuntos
Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Doenças da Aorta/cirurgia , Implante de Prótese Vascular/métodos , Prótese Vascular , Procedimentos Endovasculares/métodos , Aorta Torácica/diagnóstico por imagem , Prótese Vascular/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Humanos , Desenho de Prótese , Stents
10.
Phlebology ; 34(3): 151-155, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29945471

RESUMO

Sapheno femoral junctional tributaries are usually left untreated at the time of endovenous ablation of axial vein. The long-term clinical significance of these untreated tributaries remains elusive and there is very little research done into this area. This article reviews the fate of untreated tributaries at sapheno femoral junction following ablation of incompetent axial vein. A literature search and analysis of evidence reveal that the junctional tributaries are one of the commonest (ranges between 8% and 31%) cause for recurrence following endovenous ablation of the axial veins. Follow up of this subset of patients after their axial vein treatment should be considered to identify neoreflux in side branches at sapheno femoral junction and plan treatment.


Assuntos
Veia Femoral , Manejo da Dor , Dor , Veia Safena , Varizes , Adulto , Feminino , Veia Femoral/patologia , Veia Femoral/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Dor/patologia , Dor/fisiopatologia , Veia Safena/patologia , Veia Safena/fisiopatologia , Varizes/patologia , Varizes/fisiopatologia , Varizes/terapia
11.
Cochrane Database Syst Rev ; 12: CD011906, 2018 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-30556597

RESUMO

BACKGROUND: Vitamins and minerals play multiple functions within the central nervous system which may help to maintain brain health and optimal cognitive functioning. Supplementation of the diet with various vitamins and minerals has been suggested as a means of maintaining cognitive function, or even of preventing dementia, in later life. OBJECTIVES: To evaluate the effects of vitamin and mineral supplementation on cognitive function in cognitively healthy people aged 40 years or more. SEARCH METHODS: We searched ALOIS, the Cochrane Dementia and Cognitive Improvement Group's (CDCIG) specialised register, as well as MEDLINE, Embase, PsycINFO, CINAHL, ClinicalTrials.gov and the WHO Portal/ICTRP from inception to 26th January 2018. SELECTION CRITERIA: We included randomised controlled trials that evaluated the cognitive effects on people aged 40 years or more of any vitamin or mineral supplements taken by mouth for at least three months. DATA COLLECTION AND ANALYSIS: Study selection, data extraction, and quality assessments were done in duplicate. Vitamins were considered broadly in the categories of B vitamins, antioxidant vitamins, and combinations of both. Minerals were considered separately, where possible. If interventions and outcomes were considered sufficiently similar, then data were pooled. In order to separate short-term cognitive effects from possible longer-term effects on the trajectory of cognitive decline, data were pooled for various treatment durations from 3 months to 12 months and up to 10 years or more. MAIN RESULTS: In total, we included 28 studies with more than 83,000 participants. There were some general limitations of the evidence. Most participants were enrolled in studies which were not designed primarily to assess cognition. These studies often had no baseline cognitive assessment and used only brief cognitive assessments at follow-up. Very few studies assessed the incidence of dementia. Most study reports did not mention adverse events or made only very general statements about them. Only 10 studies had a mean follow-up > 5 years. Only two studies had participants whose mean age was < 60 years at baseline. The risk of bias in the included studies was generally low, other than a risk of attrition bias for longer-term outcomes. We considered the certainty of the evidence behind almost all results to be moderate or low.We included 14 studies with 27,882 participants which compared folic acid, vitamin B12, vitamin B6, or a combination of these to placebo. The majority of participants were aged over 60 years and had a history of cardio- or cerebrovascular disease. We found that giving B vitamin supplements to cognitively healthy adults, mainly in their 60s and 70s, probably has little or no effect on global cognitive function at any time point up to 5 years (SMD values from -0.03 to 0.06) and may also have no effect at 5-10 years (SMD -0.01). There were very sparse data on adverse effects or on incidence of cognitive impairment or dementia.We included 8 studies with 47,840 participants in which the active intervention was one or more of the antioxidant vitamins: ß-carotene, vitamin C or vitamin E. Results were mixed. For overall cognitive function, there was low-certainty evidence of benefit associated with ß-carotene after a mean of 18 years of treatment (MD 0.18 TICS points, 95% CI 0.01 to 0.35) and of vitamin C after 5 years to 10 years (MD 0.46 TICS points, 95% CI 0.14 to 0.78), but not at earlier time points. From two studies which reported on dementia incidence, there was low-certainty evidence of no effect of an antioxidant vitamin combination or of vitamin E, either alone or combined with selenium. One of the included studies had been designed to look for effects on the incidence of prostate cancer; it found a statistically significant increase in prostate cancer diagnoses among men taking vitamin E.One trial with 4143 participants compared vitamin D3 (400 IU/day) and calcium supplements to placebo. We found low- to moderate-certainty evidence of no effect of vitamin D3 and calcium supplements at any time-point up to 10 years on overall cognitive function (MD after a mean of 7.8 years -0.1 MMSE points, 95% CI -0.81 to 0.61) or the incidence of dementia (HR 0.94, 95% CI 0.72 to 1.24). A pilot study with 60 participants used a higher dose of vitamin D3 (4000 IU on alternate days) and found preliminary evidence that this dose probably has no effect on cognitive function over six months.We included data from one trial of zinc and copper supplementation with 1072 participants. There was moderate-certainty evidence of little or no effect on overall cognitive function (MD 0.6 MMSE points, 95% CI -0.19 to 1.39) or on the incidence of cognitive impairment after 5 years to 10 years. A second smaller trial provided no usable data, but reported no cognitive effects of six months of supplementation with zinc gluconate.From one study with 3711 participants, there was low-certainty evidence of no effect of approximately five years of selenium supplementation on the incidence of dementia (HR 0.83, 95% CI 0.61 to 1.13).Finally, we included three trials of complex supplements (combinations of B vitamins, antioxidant vitamins, and minerals) with 6306 participants. From the one trial which assessed overall cognitive function, there was low-certainty evidence of little or no effect on the TICS (MD after a mean of 8.5 years 0.12, 95% CI -0.14 to 0.38). AUTHORS' CONCLUSIONS: We did not find evidence that any vitamin or mineral supplementation strategy for cognitively healthy adults in mid or late life has a meaningful effect on cognitive decline or dementia, although the evidence does not permit definitive conclusions. There were very few data on supplementation starting in midlife (< 60 years); studies designed to assess cognitive outcomes tended to be too short to assess maintenance of cognitive function; longer studies often had other primary outcomes and used cognitive measures which may have lacked sensitivity. The only positive signals of effect came from studies of long-term supplementation with antioxidant vitamins. These may be the most promising for further research.


Assuntos
Cognição/efeitos dos fármacos , Disfunção Cognitiva/prevenção & controle , Suplementos Nutricionais , Minerais/administração & dosagem , Vitaminas/administração & dosagem , Adulto , Idoso , Antioxidantes/administração & dosagem , Ácido Ascórbico/administração & dosagem , Cálcio/administração & dosagem , Colecalciferol/administração & dosagem , Cognição/fisiologia , Cobre/administração & dosagem , Demência/prevenção & controle , Ácido Fólico/administração & dosagem , Humanos , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Selênio/administração & dosagem , Vitamina A/administração & dosagem , Vitamina B 12/administração & dosagem , Vitamina B 6/administração & dosagem , Vitamina E/administração & dosagem , Zinco/administração & dosagem , beta Caroteno/administração & dosagem
12.
Cochrane Database Syst Rev ; 11: CD011905, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30383288

RESUMO

BACKGROUND: Vitamins and minerals have many functions in the nervous system which are important for brain health. It has been suggested that various different vitamin and mineral supplements might be useful in maintaining cognitive function and delaying the onset of dementia. In this review, we sought to examine the evidence for this in people who already had mild cognitive impairment (MCI). OBJECTIVES: To evaluate the effects of vitamin and mineral supplementation on cognitive function and the incidence of dementia in people with mild cognitive impairment. SEARCH METHODS: We searched ALOIS, the Cochrane Dementia and Cognitive Improvement Group's (CDCIG) specialised register, as well as MEDLINE, Embase, PsycINFO, CENTRAL, CINAHL, LILACs, Web of Science Core Collection, ClinicalTrials.gov, and the WHO Portal/ICTRP, from inception to 25 January 2018. SELECTION CRITERIA: We included randomised or quasi-randomised, placebo-controlled trials which evaluated orally administered vitamin or mineral supplements in participants with a diagnosis of mild cognitive impairment and which assessed the incidence of dementia or cognitive outcomes, or both. We were interested in studies applicable to the general population of older people and therefore excluded studies in which participants had severe vitamin or mineral deficiencies. DATA COLLECTION AND ANALYSIS: We sought data on our primary outcomes of dementia incidence and overall cognitive function and on secondary outcomes of episodic memory, executive function, speed of processing, quality of life, functional performance, clinical global impression, adverse events, and mortality. We conducted data collection and analysis according to standard Cochrane systematic review methods. We assessed the risk of bias of included studies using the Cochrane 'Risk of bias' assessment tool. We grouped vitamins and minerals according to their putative mechanism of action and, where we considered it to be clinically appropriate, we pooled data using random-effects methods. We used GRADE methods to assess the overall quality of evidence for each comparison and outcome. MAIN RESULTS: We included five trials with 879 participants which investigated B vitamin supplements. In four trials, the intervention was a combination of vitamins B6, B12, and folic acid; in one, it was folic acid only. Doses varied. We considered there to be some risks of performance and attrition bias and of selective outcome reporting among these trials. Our primary efficacy outcomes were the incidence of dementia and scores on measures of overall cognitive function. None of the trials reported the incidence of dementia and the evidence on overall cognitive function was of very low-quality. There was probably little or no effect of B vitamins taken for six to 24 months on episodic memory, executive function, speed of processing, or quality of life. The evidence on our other secondary clinical outcomes, including harms, was very sparse or very low-quality. There was evidence from one study that there may be a slower rate of brain atrophy over two years in participants taking B vitamins. The same study reported subgroup analyses based on the level of serum homocysteine (tHcy) at baseline and found evidence that B vitamins may improve episodic memory in those with tHcy above the median at baseline.We included one trial (n = 516) of vitamin E supplementation. Vitamin E was given as 1000 IU of alpha-tocopherol twice daily. We considered this trial to be at risk of attrition and selective reporting bias. There was probably no effect of vitamin E on the probability of progression from MCI to Alzheimer's dementia over three years (HR 1.02; 95% CI 0.74 to 1.41; n = 516; 1 study, moderate-quality evidence). There was also no evidence of an effect at intermediate time points. The available data did not allow us to conduct analyses, but the authors reported no significant effect of three years of supplementation with vitamin E on overall cognitive function, episodic memory, speed of processing, clinical global impression, functional performance, adverse events, or mortality (five deaths in each group). We considered this to be low-quality evidence.We included one trial (n = 256) of combined vitamin E and vitamin C supplementation and one trial (n = 26) of supplementation with chromium picolinate. In both cases, there was a single eligible cognitive outcome, but we considered the evidence to be very low-quality and so could not be sure of any effects. AUTHORS' CONCLUSIONS: The evidence on vitamin and mineral supplements as treatments for MCI is very limited. Three years of treatment with high-dose vitamin E probably does not reduce the risk of progression to dementia, but we have no data on this outcome for other supplements. Only B vitamins have been assessed in more than one RCT. There is no evidence for beneficial effects on cognition of supplementation with B vitamins for six to 24 months. Evidence from a single study of a reduced rate of brain atrophy in participants taking vitamin B and a beneficial effect of vitamin B on episodic memory in those with higher tHcy at baseline warrants attempted replication.


Assuntos
Ácido Ascórbico/administração & dosagem , Transtornos Cognitivos/terapia , Demência/prevenção & controle , Suplementos Nutricionais , Oligoelementos/administração & dosagem , Complexo Vitamínico B/administração & dosagem , Vitaminas/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Cognição/fisiologia , Função Executiva , Humanos , Memória Episódica , Pessoa de Meia-Idade , Mortalidade , Ácidos Picolínicos/administração & dosagem , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , alfa-Tocoferol/administração & dosagem
13.
Sci Rep ; 7(1): 2989, 2017 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-28592827

RESUMO

Metabolic phenotypes reflect both the genetic and environmental factors which contribute to the development of varicose veins (VV). This study utilises analytical techniques to provide a comprehensive metabolic picture of VV disease, with the aim of identifying putative cellular pathways of disease pathogenesis. VV (n = 80) and non-VV (n = 35) aqueous and lipid metabolite extracts were analysed using 600 MHz 1H Nuclear Magnetic Resonance spectroscopy and Ultra-Performance Liquid Chromatography Mass Spectrometry. A subset of tissue samples (8 subjects and 8 controls) were analysed for microRNA expression and the data analysed with mirBase (www.mirbase.org). Using Multivariate statistical analysis, Ingenuity pathway analysis software, DIANALAB database and published literature, the association of significant metabolites with relevant cellular pathways were understood. Higher concentrations of glutamate, taurine, myo-inositol, creatine and inosine were present in aqueous extracts and phosphatidylcholine, phosphatidylethanolamine and sphingomyelin in lipid extracts in the VV group compared with non-VV group. Out of 7 differentially expressed miRNAs, spearman correlation testing highlighted correlation of hsa-miR-642a-3p, hsa-miR-4459 and hsa-miR-135a-3p expression with inosine in the vein tissue, while miR-216a-5p, conversely, was correlated with phosphatidylcholine and phosphatidylethanolamine. Pathway analysis revealed an association of phosphatidylcholine and sphingomyelin with inflammation and myo-inositol with cellular proliferation.


Assuntos
Metaboloma , Varizes/patologia , Cromatografia Líquida de Alta Pressão , Feminino , Perfilação da Expressão Gênica , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Espectrometria de Massas , RNA Mensageiro/análise
14.
J Am Geriatr Soc ; 64(5): 1006-14, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27225356

RESUMO

OBJECTIVES: To describe the prevalence and predictors of frailty in individuals with the human immunodeficiency virus (HIV) using systematic review methodology. DESIGN: Review. SETTING: Community. PARTICIPANTS: Older adults with HIV. MEASUREMENTS: Medline, CINAHL, EMBASE, PsychInfo, and PubMed were searched for original observational studies with populations including individuals with HIV in which frailty was assessed using the frailty phenotype or a variant thereof. Studies were examined for frailty prevalence and predictors of the syndrome in those with HIV. RESULTS: Thirteen of 322 citations were included for full review. All demonstrated the presence of frailty in individuals with HIV, with prevalence ranging from 5% to 28.6% depending on population studied. HIV was a risk factor for frailty. Predictors of frailty included older age, comorbidities, diagnosis of acquired immunodeficiency syndrome, and low current CD4(+) cell count. CONCLUSION: HIV appears to be an independent risk factor for frailty, with frailty occurring in individuals with HIV at rates comparable with older individuals without HIV. Heterogeneity in study populations and frailty assessment measures hamper accurate description of the problem. Future longitudinal work with standardized methodology is needed to describe prevalence accurately and confirm predictors.


Assuntos
Idoso Fragilizado , Infecções por HIV/complicações , Idoso , Humanos , Prevalência , Fatores de Risco
15.
Analyst ; 140(22): 7586-97, 2015 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-26468486

RESUMO

Human vein tissue is an important matrix to examine when investigating vascular diseases with respect to understanding underlying disease mechanisms. Here, we report the development of an extraction protocol for multi-platform metabolic profiling of human vein tissue. For the first stage of the optimization, two different ratios of methanol/water and 5 organic solvents--namely dichloromethane, chloroform, isopropanol, hexane and methyl tert-butyl ether (MTBE) solutions with methanol--were tested for polar and organic compound extraction, respectively. The extraction output was assessed using (1)H Nuclear Magnetic Resonance (NMR) spectroscopy and a panel of Ultra Performance Liquid Chromatography-Mass Spectrometry (UPLC-MS) methodologies. On the basis of the reproducibility of extraction replicates and metabolic coverage, the optimal aqueous (methanol/water) and organic (MTBE/methanol) solvents identified from the first stage were used in a sequential approach for metabolite extraction, altering the order of solvent-mixture addition. The combination of organic metabolite extraction with MTBE/methanol (3 : 1) followed by extraction of polar compounds with methanol/water (1 : 1) was shown to be the best method for extracting metabolites from human vein tissue in terms of reproducibility and number of signals detected and could be used as a single extraction procedure to serve both NMR and UPLC-MS analyses. Molecular classes such as triacylglycerols, phosphatidylcholines, phosphatidylethanolamines, sphingolipids, purines, and pyrimidines were reproducibly extracted. This study enabled an optimal extraction protocol for robust and more comprehensive metabolome coverage for human vein tissue. Many of the physiological and pathological processes affecting the composition of human vein tissue are common to other tissues and hence the extraction method developed in this study can be generically applied.


Assuntos
Metaboloma , Metabolômica/métodos , Veias/metabolismo , Fracionamento Químico/métodos , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas/métodos , Metanol/química , Solventes/química , Veias/química , Água/química
16.
Nat Prod Commun ; 10(8): 1395-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26434126

RESUMO

Glibenclamide and thymoquinone plasma concentrations were analysed using a sensitive RP-HPLC method, and non-compartmental model pharmacokinetic parameters were calculated. The maximum reduction in blood glucose level was observed 3 hours following glibenclamide administration, which reached 47.4% of baseline, whereas it was reduced by 53.0% to 56.2% when co-administrated with thymoquinone. Plasma concentration of glibenclamide was increased by 13.4% and 21.8% by the co-administration of thymoquinone as single and multiple doses, respectively (P<0.05). The AUC and TI/2 of glibenclamide were also increased respectively by 32.0% and 17.4% with a thymoquinone single dose, and by 52.5% and 92.8% after chronic treatment. Furthermore, diabetic rats treated with thymoquinone demonstrated a marked decrease in hepatic protein expressions of CYP3A2 and CYP2C 11 enzymes that are responsible for the metabolism of glibenclamide. The current data suggest that thymoquinone exhibits a synergistic effect with glibenclamide on glucose level, which could be explained by reducing CYP450 activity at the protein level.


Assuntos
Benzoquinonas/administração & dosagem , Diabetes Mellitus Experimental/tratamento farmacológico , Glibureto/farmacocinética , Hipoglicemiantes/farmacocinética , Nigella/química , Extratos Vegetais/administração & dosagem , Animais , Hidrocarboneto de Aril Hidroxilases/genética , Hidrocarboneto de Aril Hidroxilases/metabolismo , Glicemia/metabolismo , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Família 2 do Citocromo P450 , Diabetes Mellitus Experimental/enzimologia , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Modelos Animais de Doenças , Interações Medicamentosas , Humanos , Masculino , Ratos , Ratos Wistar , Esteroide 16-alfa-Hidroxilase/genética , Esteroide 16-alfa-Hidroxilase/metabolismo
17.
Anal Chem ; 87(8): 4184-93, 2015 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-25664760

RESUMO

Metabolic profiling studies aim to achieve broad metabolome coverage in specific biological samples. However, wide metabolome coverage has proven difficult to achieve, mostly because of the diverse physicochemical properties of small molecules, obligating analysts to seek multiplatform and multimethod approaches. Challenges are even greater when it comes to applications to tissue samples, where tissue lysis and metabolite extraction can induce significant systematic variation in composition. We have developed a pipeline for obtaining the aqueous and organic compounds from diseased arterial tissue using two consecutive extractions, followed by a different untargeted UPLC-MS analysis method for each extract. Methods were rationally chosen and optimized to address the different physicochemical properties of each extract: hydrophilic interaction liquid chromatography (HILIC) for the aqueous extract and reversed-phase chromatography for the organic. This pipeline can be generic for tissue analysis as demonstrated by applications to different tissue types. The experimental setup and fast turnaround time of the two methods contributed toward obtaining highly reproducible features with exceptional chromatographic performance (CV % < 0.5%), making this pipeline suitable for metabolic profiling applications. We structurally assigned 226 metabolites from a range of chemical classes (e.g., carnitines, α-amino acids, purines, pyrimidines, phospholipids, sphingolipids, free fatty acids, and glycerolipids) which were mapped to their corresponding pathways, biological functions and known disease mechanisms. The combination of the two untargeted UPLC-MS methods showed high metabolite complementarity. We demonstrate the application of this pipeline to cardiovascular disease, where we show that the analyzed diseased groups (n = 120) of arterial tissue could be distinguished based on their metabolic profiles.


Assuntos
Artérias/química , Aminoácidos/análise , Aminoácidos/metabolismo , Artérias/metabolismo , Doenças Cardiovasculares , Carnitina/análise , Carnitina/metabolismo , Cromatografia Líquida de Alta Pressão/instrumentação , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Lipídeos/análise , Espectrometria de Massas/instrumentação , Purinas/análise , Purinas/metabolismo , Pirimidinas/análise , Pirimidinas/metabolismo
18.
Phlebology ; 29(10): 648-53, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23963729

RESUMO

OBJECTIVES: This work was presented as a poster in the American Venous Forum 25th Annual Meeting; 28 February 2013; Phoenix, Arizona, USA. Quality of life (QoL) is an important outcome measure in the treatment for chronic venous disease. The Aberdeen Varicose Vein Questionnaire (AVVQ) and the ChronIc Venous Insufficiency quality of life Questionnaire (CIVIQ-14) are two validated disease-specific QoL questionnaires in current use. The aim of this study is to evaluate the relationship between the AVVQ and the CIVIQ-14 to enable better comparison between studies and to compare these disease-specific QoL tools with generic QoL and clinician-driven tools. METHODS: Adults attending our institution for management of their varicose veins completed the AVVQ, CIVIQ-14 and EuroQol-5D (EQ-5D). Clinical data, CEAP classification and the Venous Clinical Severity Score (VCSS) were collected. The relationship between the AVVQ and CIVIQ-14 scores was analysed using Spearman's correlation. The AVVQ and CIVIQ-14 scores were also analysed with a generic QoL tool (EQ-5D) and a clinician-driven tool, the VCSS. RESULTS: One hundred patients, mean age 57.5 (44 males; 56 females), participated in the study. The median AVVQ score was 21.9 (range 0-74) and the median CIVIQ-14 score was 30 (range 0-89). A strong correlation was demonstrated between the AVVQ and CIVIQ-14 scores (r = 0.8; p < 0.0001). Strong correlation was maintained for patients with C1-3 disease (r = 0.7; p < 0.0001) and C4-6 disease (r = 0.8; p < 0.0001). The VCSS correlated strongly with the AVVQ and CIVIQ-14 scores (r = 0.7; p < 0.0001 and r = 0.7; p < 0.0001, respectively). Both the AVVQ and CIVIQ-14 scores correlated well with the EQ-5D score (r = -0.5; p < 0.0001 and r = -0.7; p < 0.0001, respectively). CONCLUSIONS: This study demonstrates that there is good correlation between two widely used varicose vein specific QoL tools (AVVQ and CIVIQ-14) across the whole spectrum of disease severity. Strong correlation exists between these disease-specific QoL tools and generic and clinician-driven tools. Our findings confirm valid comparisons between studies using either disease-specific QoL tool.


Assuntos
Qualidade de Vida , Inquéritos e Questionários , Insuficiência Venosa/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais/psicologia , Índice de Gravidade de Doença , Adulto Jovem
19.
Eur J Dent Educ ; 17(1): 10-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23279387

RESUMO

This qualitative research study identified criteria for clinical teacher quality preferences as perceived by dental students. Third and fourth year dental students at New York University College of Dentistry were given a two question, open-ended survey asking what qualities they liked most and least in a clinical teacher. Responses were collected until data saturation was achieved. A total of 157 respondents provided a total of 995 written comments. Descriptive words within the responses were coded and grouped into key words, according to similar relationships, and further refined into 17 defined categories. Three core themes, Character, Competence and Communication, emerged from these 17 categories, which were validated according to specific references found in the existing educational literature. 'Character' comprised nine of the 17 defined categories: (caring, motivation, empathy, patience, professionalism, available, fairness, happiness, patient-centred) and yielded 59.1% of total student responses; 'Competence' consisted of five categories: knowledgeable, expertise, efficient, skilful, effective (29.2%); and 'Communication' represented the remaining three categories: feedback, approachable and interpersonal communication (11.7%). Positive and negative responses related to the defined category of caring were cited by 59.2% of all students. Motivation was the next highest category, cited by 45.9% of students. Non-cognitive attributes, especially those in the Character theme, comprised the majority of student comments. Because students' perceptions are so critical to understanding clinical teaching effectiveness in dental education, these findings can be used to develop assessments to measure clinical teaching effectiveness, to create criteria for the hiring and promotion of clinical faculty and to plan faculty development programming.


Assuntos
Educação em Odontologia/métodos , Docentes de Odontologia/normas , Competência Profissional , Estudantes de Odontologia , Coleta de Dados , Humanos , New York , Pesquisa Qualitativa
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