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2.
Lancet Infect Dis ; 20(3): 381, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32112768
3.
Int J Behav Med ; 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32030598

RESUMO

OBJECTIVE: Evidence links trait hostility with components of the metabolic syndrome (MetS), a clustering of cardiometabolic risk factors, but which hostility dimensions (e.g., expressive or cognitive hostility) relate to MetS are not well known. Further, there may be age and sex differences in the extent to which hostility dimensions relate to MetS. The present study evaluated associations between dimensions of hostility and the metabolic syndrome and its individual components as well as the moderating effects of sex and age. METHODS: In a cross-sectional sample of 478 employed adults, a principal component analysis from common trait hostility questionnaires yielded a two-factor solution: expressive hostility (anger and aggression) and cognitive hostility (cynicism). Each of these two components of hostility was examined as predictors of each of two aggregated MetS outcomes: a dichotomous measure of MetS, based upon the NCEP-ATP III definition, and a continuous measure based upon the average of standardized scores for each component; and they were examined as predictors of individual MetS components as well. RESULTS: Expressive hostility was associated with MetS severity (b = 0.110, p = 0.04) and waist circumference (b = 2.75, p = 0.01). Moderation analyses revealed that elevated expressive hostility was associated with elevated waist circumference in women but not men. Cognitive hostility was not related to any metabolic syndrome component or aggregated outcome, and no moderation was observed. CONCLUSIONS: Among multiple individual components and two aggregated scores, only trait dispositions to expressed hostile affect and behavior were associated with MetS severity and waist circumference. The effects were small but statistically significant. The association between cognitive hostility and metabolic syndrome measures may not be robust in a large sample of healthy, midlife adults.

5.
BMC Nephrol ; 21(1): 58, 2020 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-32087678

RESUMO

BACKGROUND: Fabry disease (FD) is a rare, lysosomal storage disorder caused by the absence or deficiency of the enzyme alpha-galactosidase A (α-Gal A) that leads to the abnormal accumulation of the lipid globotriaosylceramide (GB3) in a variety of cell types and tissues throughout the body. FD has an x-linked inheritance pattern. Previously thought to be only carriers, females can also experience FD symptomatology. Symptoms vary in type and severity from patient to patient and tend to increase in severity with age. FD symptoms are non-specific and may be shared with those of other diseases. Misdiagnoses and diagnostic delays are common, often resulting in progressive, irreversible tissue damage. The estimated prevalence of FD in the general population is 1:40,000 to 1:117,000 individuals. However, it is estimated that the prevalence of FD in the dialysis population is 0.12 to 0.7%. Little is known about the prevalence of FD in the broader Chronic Kidney Disease (CKD) population. METHODS: This is an epidemiological study of the prevalence of FD in CKD patents identified from the public renal speciality practices in Queensland, Australia. A cascade approach to screening is being employed with dried blood spot testing for blood levels of alpha-galactosidase A (Alpha-Gal), with follow-up testing for patients with abnormal results by plasma levels of globotriaosylsphingosine (Lyso-GB3) for females and non-definitive cases in males. A diagnosis of FD is confirmed through genetic testing of the GLA gene in cases suspected of having FD based upon Alpha-Gal and Lyso-GB3 testing. DISCUSSION: Expected outcomes of this study include more information about the prevalence of FD at all stages of CKD, including for both males and females. The study may also provide information about common characteristics of FD to assist with diagnosis and optimal management/treatment. Screening is also available for family members of diagnosed patients, with potential for early diagnosis of FD and intervention for those individuals. TRIAL REGISTRATION: Queensland Health Database of Research Activity (DORA, https://dora.health.qld.gov.au) pj09946 (Registered 3rd July 2017).

6.
Orphanet J Rare Dis ; 15(1): 10, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31931840

RESUMO

AIM: To determine the prevalence of undiagnosed Fabry Disease (FD) in Western Australian (WA) patients undergoing dialysis. BACKGROUND: FD is a multisystem X-linked lysosomal storage disease caused by deficient activity of alpha-galactosidase-A (α-GAL-A). Affected individuals are at risk of developing small-fibre neuropathy, rash, progressive kidney disease, hypertrophic cardiomyopathy and ischaemic stroke. Diagnosis is often delayed by years or even decades. Screening high risk population such as dialysis patients may identify patients with undiagnosed Fabry disease. METHODS: A cross-sectional study was undertaken of all adult patients receiving dialysis in WA, without previously known FD. After informed consent they were screened for α-GAL-A activity by dried blood spot samples. Low or inconclusive activity were repeated via Centogene in Rostock, Germany with GLA genetic analysis. Ethics approval was granted by Royal Perth Hospital Human Research Ethic Committee REG 14-136; site-specific approval was granted from appropriate authorities; ANZ Clinical Trials Registry U1111-1163-7629. RESULTS: Between February 2015 & September 2017, α-GAL-A activity was performed on 526 patients at 16 dialysis sites. Twenty-nine patients had initial low α-GAL-A; repeat testing & GLA genotyping showed no confirmed FD cases. The causes of false positive rates were thought to be secondary to impaired protein synthesis due to patient malnutrition and chronic inflammation, which is common among dialysis patients, in addition to poor sampling handling. CONCLUSION: Analysis of this dialysis population has shown a prevalence of 0% undiagnosed FD. False positives results may occur through impaired protein synthesis and sample handling.

7.
FASEB J ; 34(2): 2765-2773, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31908033

RESUMO

The brown adipose tissue (BAT) is a thermogenic organ that plays a major role in energy balance, obesity, and diabetes due to the potent glucose and lipid clearance that fuels its thermogenesis, which is largely mediated via sympathetic nervous system activation. However, thus far there has been little experimental validation of the hypothesis that selective neuromodulation of the sympathetic nerves innervating the BAT is sufficient to elicit thermogenesis in mice. We generated mice expressing blue light-activated channelrhodopsin-2 (ChR2) in the sympathetic nerves innervating the BAT using two different strategies: injecting the BAT of C57Bl/6J mice with AAV6-hSyn-ChR2 (H134R)-EYFP; crossbreeding tyrosine hydroxylase-Cre mice with floxed-stop ChR2-EYFP mice. The nerves in the BAT expressing ChR2 were selectively stimulated with a blue LED light positioned underneath the fat pad of anesthetized mice, while the BAT and core temperatures were simultaneously recorded. Using immunohistochemistry we confirmed the selective expression of EYFP in TH positive nerves fibers. In addition, local optogenetic stimulation of the sympathetic nerves induced significant increase in the BAT temperature followed by an increase in core temperature in mice expressing ChR2, but not in the respective controls. The BAT activation was also paralleled by increased levels of pre-UCP1 transcript. Our results demonstrate that local optogenetic stimulation of the sympathetic nerves is sufficient to elicit BAT and core thermogenesis, thus suggesting that peripheral neuromodulation has the potential to be exploited as an alternative to pharmacotherapies to elicit organ activation and thus ameliorate type 2 diabetes and/or obesity.

8.
Platelets ; : 1-7, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31893974

RESUMO

Ticagrelor is an antagonist of both platelet adenosine diphosphate (ADP) receptor P2Y12 and equilibrative nucleoside transporter-1. Optimal timing of ticagrelor cessation prior to coronary artery bypass grafting (CABG) remains unclear. We characterized the offset of ticagrelor's effects on platelets and cellular adenosine uptake in ticagrelor-treated patients (n = 13) awaiting CABG. Blood was drawn prior to CABG at multiple timepoints 2 to 120 (h) after the last dose of ticagrelor. Platelet function (n = 13) was assessed with multiple electrode aggregometry (MEA), expressed as arbitrary units (U) derived from area-under-the-curve (AUC) in response to ADP, and inhibition of adenosine uptake by high-performance liquid chromatography (n = 7). Mean±SD AUC was 20.3 ± 8.2 U (2 h post-ticagrelor), 33.0 ± 18.3U (24 h), 56.6 ± 30.6U (48 h), 61.4 ± 20.2U (72 h), 82.8 ± 24.2U (96 h) and 96.0 ± 15.3U (120 h). There was a significant difference between 72 h and 120 h (p = .007), but not between 96 h and 120 h (p > .99). By 96 h, all patients had AUC >31U, an accepted cutoff below which surgical bleeding risk is increased. Adenosine uptake showed no significant differences between the timepoints. These data suggest it takes 4 days for platelet reactivity to recover sufficiently after cessation of ticagrelor to avoid the excess risk of CABG-related bleeding. Discontinuing ticagrelor had no measurable effect on cellular adenosine uptake.

9.
Neuron ; 105(6): 1036-1047.e5, 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-31954621

RESUMO

Dopamine is involved in physiological processes like learning and memory, motor control and reward, and pathological conditions such as Parkinson's disease and addiction. In contrast to the extensive studies on neurons, astrocyte involvement in dopaminergic signaling remains largely unknown. Using transgenic mice, optogenetics, and pharmacogenetics, we studied the role of astrocytes on the dopaminergic system. We show that in freely behaving mice, astrocytes in the nucleus accumbens (NAc), a key reward center in the brain, respond with Ca2+ elevations to synaptically released dopamine, a phenomenon enhanced by amphetamine. In brain slices, synaptically released dopamine increases astrocyte Ca2+, stimulates ATP/adenosine release, and depresses excitatory synaptic transmission through activation of presynaptic A1 receptors. Amphetamine depresses neurotransmission through stimulation of astrocytes and the consequent A1 receptor activation. Furthermore, astrocytes modulate the acute behavioral psychomotor effects of amphetamine. Therefore, astrocytes mediate the dopamine- and amphetamine-induced synaptic regulation, revealing a novel cellular pathway in the brain reward system.

10.
Nature ; 577(7792): 665-670, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31969706

RESUMO

Our knowledge of ancient human population structure in sub-Saharan Africa, particularly prior to the advent of food production, remains limited. Here we report genome-wide DNA data from four children-two of whom were buried approximately 8,000 years ago and two 3,000 years ago-from Shum Laka (Cameroon), one of the earliest known archaeological sites within the probable homeland of the Bantu language group1-11. One individual carried the deeply divergent Y chromosome haplogroup A00, which today is found almost exclusively in the same region12,13. However, the genome-wide ancestry profiles of all four individuals are most similar to those of present-day hunter-gatherers from western Central Africa, which implies that populations in western Cameroon today-as well as speakers of Bantu languages from across the continent-are not descended substantially from the population represented by these four people. We infer an Africa-wide phylogeny that features widespread admixture and three prominent radiations, including one that gave rise to at least four major lineages deep in the history of modern humans.

13.
Paediatr Anaesth ; 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31886922

RESUMO

Anesthesia for pediatric airway procedures constitutes a true art form that requires training and experience. Communication between anesthetist and surgeon to establish procedure goals is essential in determining the most appropriate anesthetic management. But does the mode of anesthesia have an impact? Traditionally, inhalational anesthesia was the most common anesthesia technique used during airway surgery. Introduction of agents used for total intravenous anesthesia (TIVA) such as propofol, short-acting opioids, midazolam, and dexmedetomidine has driven change in practice. Ongoing debates abound as to the advantages and disadvantages of volatile-based anesthesia versus TIVA. This pro-con discussion examines both volatiles and TIVA, from the perspective of effectiveness, safety, cost, and environmental impact, in an endeavor to justify which technique is the best specifically for pediatric airway procedures.

14.
Artigo em Inglês | MEDLINE | ID: mdl-31860096

RESUMO

BACKGROUND AND OBJECTIVES: The Acute Kidney Outreach to Reduce Deterioration and Death trial was a large pilot study for a cluster-randomized trial of acute kidney injury (AKI) outreach. METHODS: An observational control (before) phase was conducted in two teaching hospitals (9 miles apart) and their respective catchment areas. In the intervention (after) phase, a working-hours AKI outreach service operated for the intervention hospital/area for 20 weeks, with the other site acting as a control. All AKI alerts in both hospital and community patients were screened for inclusion. Major exclusion criteria were patients who were at the end of life, unlikely to benefit from outreach, lacking mental capacity or already referred to the renal team. The intervention arm included a model of escalation of renal care to AKI patients, depending on AKI stage. The 30-day primary outcome was a combination of death, or deterioration, as shown by any need for dialysis or progression in AKI stage. A total of 1762 adult patients were recruited; 744 at the intervention site during the after phase. RESULTS: A median of 3.0 non-medication recommendations and 0.5 medication-related recommendations per patient were made by the outreach team a median of 15.7 h after the AKI alert. Relatively low rates of the primary outcomes of death within 30 days (11-15%) or requirement for dialysis (0.4-3.7%) were seen across all four groups. In an exploratory analysis, at the intervention hospital during the after phase, there was an odds ratio for the combined primary outcome of 0.73 (95% confidence interval 0.42-1.26; P = 0.26). CONCLUSIONS: An AKI outreach service can provide standardized specialist care to those with AKI across a healthcare economy. Trials assessing AKI outreach may benefit from focusing on those patients with 'mid-range' prognosis, where nephrological intervention could have the most impact.

15.
Eur Heart J Acute Cardiovasc Care ; : 2048872619878075, 2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31868508

RESUMO

BACKGROUND: Inflammation plays a major role in the pathophysiology of coronary artery disease. We aimed to determine whether baseline inflammatory markers were associated with clinical outcomes and the observed superiority of ticagrelor compared to clopidogrel in patients with acute coronary syndromes in the PLATO study. METHODS: Blood samples were collected from 16,400 patients within 24 hours of the onset of acute coronary syndrome, at the time of random assignment to ticagrelor or clopidogrel in the PLATO study and prior to invasive procedures. The differential white blood cell count and plasma levels of C-reactive protein, interleukin-6 and interleukin-10 were determined and their relationships with clinical outcomes were assessed according to quartiles and using continuous models. The substudy primary endpoint was a composite of cardiovascular death and myocardial infarction. RESULTS: Compared to the lowest quartile, the risk of the primary endpoint was significantly elevated in patients in the highest quartile of white blood cell count (hazard ratio (HR) 1.30; P=0.01), neutrophil count (HR 1.33; P=0.007), monocyte count (HR 1.24; P=0.004), C-reactive protein (HR 1.93; P<0.001) and interleukin-6 (HR 2.29; P<0.001). This was predominantly driven by an association with cardiovascular death. Following adjustment for clinical characteristics, troponin, cystatin C and N-terminal pro-brain-type natriuretic peptide, only white blood cell count and neutrophil count maintained a significant association with the primary endpoint. Ticagrelor had a consistent relative cardiovascular benefit compared to clopidogrel in each quartile of each of the inflammatory markers. CONCLUSIONS: Acute coronary syndrome patients with elevated levels of baseline inflammatory markers are at increased risk of adverse cardiovascular events, particularly cardiovascular death. The consistent cardiovascular benefit of ticagrelor compared to clopidogrel tended to confer a greater absolute risk reduction in patients with the highest levels of inflammatory markers, as they were at highest risk.

16.
Nat Plants ; 5(11): 1120-1128, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31685951

RESUMO

Tetraploid emmer wheat (Triticum turgidum ssp. dicoccon) is a progenitor of the world's most widely grown crop, hexaploid bread wheat (Triticum aestivum), as well as the direct ancestor of tetraploid durum wheat (T. turgidum subsp. turgidum). Emmer was one of the first cereals to be domesticated in the old world; it was cultivated from around 9700 BC in the Levant1,2 and subsequently in south-western Asia, northern Africa and Europe with the spread of Neolithic agriculture3,4. Here, we report a whole-genome sequence from a museum specimen of Egyptian emmer wheat chaff, 14C dated to the New Kingdom, 1130-1000 BC. Its genome shares haplotypes with modern domesticated emmer at loci that are associated with shattering, seed size and germination, as well as within other putative domestication loci, suggesting that these traits share a common origin before the introduction of emmer to Egypt. Its genome is otherwise unusual, carrying haplotypes that are absent from modern emmer. Genetic similarity with modern Arabian and Indian emmer landraces connects ancient Egyptian emmer with early south-eastern dispersals, whereas inferred gene flow with wild emmer from the Southern Levant signals a later connection. Our results show the importance of museum collections as sources of genetic data to uncover the history and diversity of ancient cereals.

18.
Front Immunol ; 10: 2569, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31749809

RESUMO

Thrombosis is a common consequence of infection that is associated with poor patient outcome. Nevertheless, the mechanisms by which infection-associated thrombosis is induced, maintained and resolved are poorly understood, as is the contribution thrombosis makes to host control of infection and pathogen spread. The key difference between infection-associated thrombosis and thrombosis in other circumstances is a stronger inflammation-mediated component caused by the presence of the pathogen and its products. This inflammation triggers the activation of platelets, which may accompany damage to the endothelium, resulting in fibrin deposition and thrombus formation. This process is often referred to as thrombo-inflammation. Strikingly, despite its clinical importance and despite thrombi being induced to many different pathogens, it is still unclear whether the mechanisms underlying this process are conserved and how we can best understand this process. This review summarizes thrombosis in a variety of models, including single antigen models such as LPS, and infection models using viruses and bacteria. We provide a specific focus on Salmonella Typhimurium infection as a useful model to address all stages of thrombosis during infection. We highlight how this model has helped us identify how thrombosis can appear in different organs at different times and thrombi be detected for weeks after infection in one site, yet largely be resolved within 24 h in another. Furthermore, we discuss the observation that thrombi induced to Salmonella Typhimurium are largely devoid of bacteria. Finally, we discuss the value of different therapeutic approaches to target thrombosis, the potential importance of timing in their administration and the necessity to maintain normal hemostasis after treatment. Improvements in our understanding of these processes can be used to better target infection-mediated mechanisms of thrombosis.

19.
J Bacteriol ; 202(1)2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31611288

RESUMO

The obligate intracellular pathogen Chlamydia trachomatis is a globally significant cause of sexually transmitted bacterial infections and the leading etiological agent of preventable blindness. The first-row transition metal iron (Fe) plays critical roles in chlamydial cell biology, and acquisition of this nutrient is essential for the survival and virulence of the pathogen. Nevertheless, how C. trachomatis acquires Fe from host cells is not well understood, since it lacks genes encoding known siderophore biosynthetic pathways, receptors for host Fe storage proteins, and the Fe acquisition machinery common to many bacteria. Recent studies have suggested that C. trachomatis directly acquires host Fe via the ATP-binding cassette permease YtgABCD. Here, we characterized YtgA, the periplasmic solute binding protein component of the transport pathway, which has been implicated in scavenging Fe(III) ions. The structure of Fe(III)-bound YtgA was determined at 2.0-Å resolution with the bound ion coordinated via a novel geometry (3 Ns, 2 Os [3N2O]). This unusual coordination suggested a highly plastic metal binding site in YtgA capable of interacting with other cations. Biochemical analyses showed that the metal binding site of YtgA was not restricted to interaction with only Fe(III) ions but could bind all transition metal ions examined. However, only Mn(II), Fe(II), and Ni(II) ions bound reversibly to YtgA, with Fe being the most abundant cellular transition metal in C. trachomatis Collectively, these findings show that YtgA is the metal-recruiting component of the YtgABCD permease and is most likely involved in the acquisition of Fe(II) and Mn(II) from host cells.IMPORTANCE Chlamydia trachomatis is the most common bacterial sexually transmitted infection in developed countries, with an estimated global prevalence of 4.2% in the 15- to 49-year age group. Although infection is asymptomatic in more than 80% of infected women, about 10% of cases result in serious disease. Infection by C. trachomatis is dependent on the ability to acquire essential nutrients, such as the transition metal iron, from host cells. In this study, we show that iron is the most abundant transition metal in C. trachomatis and report the structural and biochemical properties of the iron-recruiting protein YtgA. Knowledge of the high-resolution structure of YtgA will provide a platform for future structure-based antimicrobial design approaches.

20.
Physiol Rep ; 7(20): e14256, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31650716

RESUMO

In humans, prefrontal cortical areas are known to support goal-directed behaviors, mediating a variety of functions that render behavior more flexible in the face of changing environmental demands. In mice, these functions are mediated by homologous regions within medial prefrontal cortex (mPFC) and rely heavily on proper dopaminergic tone. Comprised of two major subtypes, pyramidal tract (PT) and intratelencephalic (IT), layer V pyramidal cells serve as the major outputs of the mPFC, targeting brainstem nuclei and the contralateral hemisphere, respectively. However, it remains relatively unknown how cortical inputs targeting these subtypes are integrated. We explored how layer V pyramidal cell subtypes integrate commissural inputs, which integrate information flow between the hemispheres. An optogenetic approach was used to elicit commissural fiber activation onto PT and IT cells and the effects of D1 receptor activation on elicited EPSPs were explored. We showed that commissural inputs into PT and IT cells elicit facilitating and depressing EPSP patterns, respectively. D1 receptor activation increased the initial EPSP amplitude, enhanced EPSP facilitation, and prolonged EPSP decay time constant in PT cells. In IT cells, D1 receptor activation increased commissural-evoked initial EPSP amplitude but did not affect facilitation or EPSP shape. Furthermore, D1 receptor activation elicited burst firing in a subset of PT cells in response to commissural fiber activation. Combined, these results lend insight into the role of dopamine in promoting persistent firing and temporal integration in PT and IT cells, respectively, that in turn may contribute to working memory functions.

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