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1.
J Am Soc Nephrol ; 34(8): 1433-1444, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37228030

RESUMO

SIGNIFICANCE STATEMENT: Lower serum bicarbonate levels, even within the normal range, are strongly linked to risks of cardiovascular disease in CKD, possibly by modifying vascular function. In this randomized, controlled trial, treatment with sodium bicarbonate (NaHCO 3 ) did not improve vascular endothelial function or reduce arterial stiffness in participants with CKD stage 3b-4 with normal serum bicarbonate levels. In addition, NaHCO 3 treatment did not reduce left ventricular mass index. NaHCO 3 did increase plasma bicarbonate levels and urinary citrate excretion and reduce urinary ammonium excretion, indicating that the intervention was indeed effective. NaHCO 3 therapy was safe with no significant changes in BP, weight, or edema. These results do not support the use of NaHCO 3 for vascular dysfunction in participants with CKD. BACKGROUND: Lower serum bicarbonate levels, even within the normal range, are strongly linked to risks of cardiovascular disease in CKD, possibly by modifying vascular function. Prospective interventional trials with sodium bicarbonate (NaHCO 3 ) are lacking. METHODS: We conducted a randomized, double-blind, placebo-controlled trial examining the effect of NaHCO 3 on vascular function in 109 patients with CKD stage 3b-4 (eGFR 15-44 ml/min per 1.73 m 2 ) with normal serum bicarbonate levels (22-27 mEq/L). Participants were randomized 1:1 to NaHCO 3 or placebo at a dose of 0.5 mEq/lean body weight-kg per day for 12 months. The coprimary end points were change in brachial artery flow-mediated dilation (FMD) and change in aortic pulse wave velocity over 12 months. RESULTS: Ninety patients completed this study. After 12 months, plasma bicarbonate levels increased significantly in the NaHCO 3 group compared with placebo (mean [SD] difference between groups 1.35±2.1, P = 0.003). NaHCO 3 treatment did not result in a significant improvement in aortic pulse wave velocity from baseline. NaHCO 3 did result in a significant increase in flow-mediated dilation after 1 month; however, this effect disappeared at 6 and 12 months. NaHCO 3 resulted in a significant increase in 24-hour urine citrate and pH and a significant decrease in 24-hour urine ammonia. There was no significant change in left ventricular mass index, ejection fraction, or eGFR with NaHCO 3 . NaHCO 3 treatment was safe and well-tolerated with no significant changes in BP, antihypertensive medication, weight, plasma calcium, or potassium levels. CONCLUSION: Our results do not support the use of NaHCO 3 for vascular dysfunction in participants with CKD and normal serum bicarbonate levels.


Assuntos
Doenças Cardiovasculares , Insuficiência Renal Crônica , Humanos , Bicarbonato de Sódio/uso terapêutico , Bicarbonatos , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Análise de Onda de Pulso , Estudos Prospectivos , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/tratamento farmacológico , Método Duplo-Cego
2.
Am J Nephrol ; 54(5-6): 165-174, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37231790

RESUMO

INTRODUCTION: Cerebrovascular dysfunction, characterized by increased brain pulsatile flow, reduced cerebrovascular reactivity, and cerebral hypoperfusion precedes the onset of dementia and is linked to cognitive dysfunction. Autosomal dominant polycystic kidney disease (ADPKD) may increase the risk of dementia, and intracranial aneurysms are more prevalent in ADPKD patients. However, cerebrovascular function has not been previously characterized in patients with ADPKD. METHODS: Using transcranial Doppler, we compared middle cerebral artery (MCA) pulsatility index (PI, cerebrovascular stiffness) and MCA blood velocity response to hypercapnia (normalized for blood pressure and end-tidal CO2, cerebrovascular reactivity) in patients with early-stage ADPKD versus age-matched healthy controls. We also administered the NIH cognitive toolbox (cognitive function) and measured carotid-femoral pulse-wave velocity (PWV, aortic stiffness). RESULTS: Fifteen participants with ADPKD (9F, 27 ± 4 yrs, eGFR: 106 ± 22 mL/min/1.73 m2) were compared to 15 healthy controls (8F, 29 ± 4 yrs, eGFR: 109 ± 14 mL/min/1.73 m2). MCA PI was unexpectedly lower in ADPKD (0.71 ± 0.07) versus controls (0.82 ± 0.09 AU; p < 0.001); however, normalized MCA blood velocity in response to hypercapnia did not differ between groups (2.0 ± 1.2 vs. 2.1 ± 0.8 %Δ/mm Hg; p = 0.85). Lower MCA PI was associated with a lower crystalized composite score (cognition), which persisted after adjustment for age, sex, eGFR, and education (ß = 0.58, p = 0.007). There was no association of MCA PI with carotid-femoral PWV (r = 0.01, p = 0.96), despite greater carotid-femoral PWV in ADPKD, suggesting MCA PI reflects vascular properties other than arterial stiffness (such as low wall shear stress) in ADPKD. DISCUSSION/CONCLUSION: MCA PI is lower in patients with ADPKD. Follow-up research on this observation is merited as low PI has been associated with intracranial aneurysm in other populations.


Assuntos
Demência , Rim Policístico Autossômico Dominante , Rigidez Vascular , Humanos , Rim Policístico Autossômico Dominante/complicações , Hipercapnia , Pressão Sanguínea/fisiologia , Cognição/fisiologia , Velocidade do Fluxo Sanguíneo/fisiologia
3.
Epidemiol Infect ; 151: e50, 2023 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-36960728

RESUMO

Around 0.4% of pregnant women in England have chronic hepatitis B virus (HBV) infection and need services to prevent vertical transmission. In this national audit, sociodemographic, clinical and laboratory information was requested from all maternity units in England for hepatitis B surface antigen-positive women initiating antenatal care in 2014. We describe these women's characteristics and indicators of access to/uptake of healthcare. Of 2542 pregnancies in 2538 women, median maternal age was 31 [IQR 27, 35] years, 94% (1986/2109) were non-UK born (25% (228/923) having arrived into the UK <2 years previously) and 32% (794/2473) had ⩾2 previous live births. In 39%, English levels were basic/less than basic. Antenatal care was initiated at median 11.3 [IQR 9.6, 14] gestation weeks, and 'late' (⩾20 weeks) in 10% (251/2491). In 70% (1783/2533) of pregnancies, HBV had been previously diagnosed and 11.8% (288/2450) had ⩾1 marker of higher infectivity. Missed specialist appointments were reported in 18% (426/2339). Late antenatal care and/or missed specialist appointments were more common in pregnancies among women lacking basic English, arriving in the UK ⩽2 years previously, newly HBV diagnosed, aged <25 years and/or with ⩾2 previous live births. We show overlapping groups of pregnant women with chronic HBV vulnerable to delayed or incomplete care.


Assuntos
Hepatite B Crônica , Hepatite B , Complicações Infecciosas na Gravidez , Feminino , Gravidez , Humanos , Gestantes , Hepatite B Crônica/epidemiologia , Hepatite B Crônica/prevenção & controle , Hepatite B/epidemiologia , Hepatite B/diagnóstico , Cuidado Pré-Natal , Complicações Infecciosas na Gravidez/epidemiologia , Vírus da Hepatite B , Antígenos de Superfície da Hepatite B , Inglaterra/epidemiologia , Transmissão Vertical de Doenças Infecciosas/prevenção & controle
4.
Matern Child Nutr ; 19(1): e13451, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36349962

RESUMO

Evidence suggests children HIV-exposed and uninfected (CHEU) experience poor growth. We analysed child anthropometrics and explored factors associated with stunting among Malawian CHEU. Mothers with HIV and their infants HIV-exposed were enroled in a nationally representative prospective cohort within the National Evaluation of Malawi's Prevention of Mother-to-Child HIV Transmission Programme after Option B+ implementation (2014-2018). Anthropometry was measured at enrolment (age 1-6 months), visit 1 (approximately 12 months), and visit 2 (approximately 24 months). Weight-for-age (WAZ) and length-for-age (LAZ) z-scores were calculated using World Health Organization Growth Standards; underweight and stunting were defined as WAZ and LAZ more than 2 standard deviations below the reference median. Multivariable logistic regression restricted to CHEU aged 24 months (±3 months) was used to identify factors associated with stunting. Among 1211 CHEU, 562/1211 attended visit 2, of which 529 were aged 24 months (±3 months) and were included. At age 24 months, 40.4% of CHEU were stunted and/or underweight, respectively. In multi-variable analysis, adjusting for child age and sex, the odds of stunting were higher among CHEU with infectious disease diagnosis compared to those with no diagnosis (adjusted odds ratio = 3.35 [95% confidence interval: 1.82-6.17]), which was modified by co-trimoxazole prophylaxis (p = 0.028). Infant low birthweight was associated with an increased odds of stunting; optimal feeding and maternal employment were correlated with reduced odds. This is one of the first studies examining CHEU growth since Option B+. Interventions to improve linear growth among CHEU should address their multi-faceted health risks, alongside maternal ART prescription, and follow-up of mother-child pairs.


Assuntos
Infecções por HIV , Transmissão Vertical de Doenças Infecciosas , Lactente , Feminino , Humanos , Pré-Escolar , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , HIV , Magreza/epidemiologia , Estudos Prospectivos , Malaui/epidemiologia , Infecções por HIV/tratamento farmacológico , Transtornos do Crescimento/epidemiologia , Fatores de Risco
5.
Emerg Infect Dis ; 28(2): 473-475, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35076369

RESUMO

To determine the extent of exposure to Zika virus (ZIKV) and chikungunya virus (CHIKV) in Jamaica, we collected serum from 584 pregnant women during 2017-2019. We found that 15.6% had antibodies against ZIKV and 83.6% against CHIKV. These results indicate potential recirculation of ZIKV but not CHIKV in the near future.


Assuntos
Febre de Chikungunya , Vírus Chikungunya , Dengue , Infecção por Zika virus , Zika virus , Febre de Chikungunya/epidemiologia , Feminino , Humanos , Jamaica/epidemiologia , Gravidez , Estudos Soroepidemiológicos , Infecção por Zika virus/epidemiologia
6.
Mem Cognit ; 50(3): 586-600, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34553341

RESUMO

While semantic and episodic memory may be distinct memory systems, their interdependence is substantial. For instance, decades of work have shown that semantic knowledge facilitates episodic memory. Here, we aim to clarify this interactive relationship by determining whether semantic knowledge facilitates the acquisition of new episodic memories, in part, by influencing an encoding mechanism, event segmentation. In the current study, we evaluated the extent to which semantic knowledge shapes how people segment ongoing activity and how such knowledge-related benefits in segmentation affect episodic memory performance. To investigate these effects, we combined data across three studies that had young and older adults segment and remember videos of everyday activities that were either familiar or unfamiliar to their age group. We found age-related differences in event-segmentation ability and memory performance, but only when older adults lacked semantic knowledge. Most importantly, when they had access to relevant semantic knowledge, older adults segmented and remembered information similar to young adults. Our findings indicate that older adults can use semantic knowledge to effectively encode and retrieve everyday information. These effects suggest that future interventions can leverage older adults' intact semantic knowledge to attenuate age-related deficits in event segmentation and episodic long-term memory.


Assuntos
Memória Episódica , Idoso , Envelhecimento , Humanos , Conhecimento , Rememoração Mental , Semântica , Adulto Jovem
7.
Mem Cognit ; 49(4): 660-674, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33415711

RESUMO

Much research has shown that experts possess superior memory in their domain of expertise. This memory benefit has been proposed to be the result of various encoding mechanisms, such as chunking and differentiation. Another potential encoding mechanism that is associated with memory is event segmentation, which is the process by which people parse continuous information into meaningful, discrete units. Previous research has found evidence that segmentation, to some extent, is affected by top-down processing. To date, few studies have investigated the influence of expertise on segmentation, and questions about expertise, segmentation ability, and their impact on memory remain. The goal of the current study was to investigate the influence of expertise on segmentation and memory ability for two different domains: basketball and Overwatch. Participants with high and low knowledge for basketball and with low knowledge for Overwatch viewed and segmented videos at coarse and fine grains, then completed memory tests. Differences in segmentation ability and memory were present between experts and control novices, specifically for the basketball videos; however, experts' segmentation only predicted memory for activities for which knowledge was lacking. Overall, this research suggests that experts' superior memory is not due to their segmentation ability and contributes to a growing body of literature showing evidence supporting conceptual effects on segmentation.


Assuntos
Memória , Humanos
8.
Am J Kidney Dis ; 74(2): 213-223, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30803706

RESUMO

RATIONALE & OBJECTIVE: Vascular dysfunction, characterized by impaired vascular endothelial function and increased large-elastic artery stiffness, is evident early in autosomal dominant polycystic kidney disease (ADPKD) and is an important predictor of cardiovascular events and mortality. Aldosterone excess has been implicated in the development of endothelial dysfunction and arterial stiffness, in part by causing increased oxidative stress and inflammation. We hypothesized that aldosterone antagonism would reduce vascular dysfunction in patients with early-stage ADPKD. STUDY DESIGN: Prospective, randomized, controlled, double-blind, clinical trial. SETTING & PARTICIPANTS: 61 adults aged 20 to 55 years with ADPKD, estimated glomerular filtration rate ≥ 60mL/min/1.73m2, and receiving a renin-angiotensin-aldosterone system inhibitor. INTERVENTION: Spironolactone (maximum dose, 50mg/d) or placebo for 24 weeks. OUTCOMES: Change in brachial artery flow-mediated dilation (FMDBA) was the primary end point and change in carotid-femoral pulse-wave velocity (CFPWV) was the secondary end point. RESULTS: 60 participants completed the trial. Participants had a mean age of 34±10 (SD) years, 54% were women, and 84% were non-Hispanic white. Spironolactone did not change FMDBA (8.0% ± 5.5% and 7.8% ± 4.3% at baseline and 24 weeks, respectively, vs corresponding values in the placebo group of 8.4% ± 6.2% and 8.0% ± 4.6%; P=0.9for comparison of change between groups) or CFPWV (640±127 and 603±101cm/s at baseline and 24 weeks, respectively, vs corresponding values in the placebo group of 659±138 and 658±131cm/s; P=0.1). Brachial systolic blood pressure was reduced with spironolactone (median change, -6 [IQR, -15, 1] vs -2 [IQR, -7, 10] mm Hg in the placebo group; P=0.04). Spironolactone did not change the majority of circulating and/or endothelial cell markers of oxidative stress/inflammation and did not change vascular oxidative stress. LIMITATIONS: Low level of baseline vascular dysfunction; lack of aldosterone measurements. CONCLUSIONS: 24 weeks of aldosterone antagonism reduced systolic blood pressure without changing vascular function in patients with early-stage ADPKD. FUNDING: NIDDK, NIH National Center for Advancing Translational Sciences, and the Zell Family Foundation. TRIAL REGISTRATION: Registered at ClinicalTrials.gov with study number NCT01853553.


Assuntos
Vasos Sanguíneos/efeitos dos fármacos , Vasos Sanguíneos/fisiopatologia , Antagonistas de Receptores de Mineralocorticoides/farmacologia , Rim Policístico Autossômico Dominante/fisiopatologia , Espironolactona/farmacologia , Adulto , Pressão Sanguínea/efeitos dos fármacos , Método Duplo-Cego , Feminino , Humanos , Masculino , Estudos Prospectivos , Adulto Jovem
9.
J Viral Hepat ; 26(8): 961-968, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30980773

RESUMO

The burden of paediatric Hepatitis C virus (HCV) infection across Europe is unknown, as are current policies regarding monitoring and treatment. This collaborative study aimed to collect aggregate data to characterise the population of ≤18-year-olds with HCV infection in specialist follow up in a 12-month period (2016) across the PENTAHep European consortium, and investigate current policies around monitoring and treatment. A cross-sectional, web-based survey was distributed in April 2017 to 50 paediatricians in 19 European countries, covering patients' profile, and monitoring and treatment practices. Responses were received from 38/50 clinicians collectively caring for 663 children with chronic HCV infection of whom three-quarters were aged ≥6 years and 90% vertically infected. HCV genotype 1 was the most common (n 380; 57.3%), followed by genotype 3, 4 and 2. Seventeen children (3%) with chronic HCV infection were diagnosed with cirrhosis, and six were reported to have received liver transplantation for HCV-related liver disease. The majority (n 425; 64.1%) of the European children with HCV infection remained treatment-naive in 2016. Age affected clinicians' attitudes towards treatment; 94% reported being willing to use direct-acting antivirals, if available, in adolescents (aged ≥11 years), 78% in children aged 6-10 and 42% in those 3-5 years of age (Pearson correlation coefficient -0.98; P 0.0001). This survey provides the largest characterisation of the population of children in clinical follow-up for chronic HCV infection in Europe, alongside important contextual information on their management and treatment. Discussion is needed around strategies and criteria for use of direct-acting antivirals in these children.


Assuntos
Hepatite C Crônica/epidemiologia , Hepatite C Crônica/terapia , Pediatras/estatística & dados numéricos , Adolescente , Fatores Etários , Antivirais/uso terapêutico , Atitude do Pessoal de Saúde , Criança , Pré-Escolar , Estudos Transversais , Europa (Continente)/epidemiologia , Feminino , Genótipo , Pesquisas sobre Atenção à Saúde , Hepacivirus/genética , Hepatite C Crônica/transmissão , Humanos , Lactente , Recém-Nascido , Masculino
10.
Mem Cognit ; 47(6): 1173-1187, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30915653

RESUMO

Knowledge benefits episodic memory, particularly when provided before encoding (Anderson & Pichert in Journal of Verbal Learning and Verbal Behavior, 17(1), 1-12, 1978; Bransford & Johnson in Journal of Verbal Learning and Verbal Behavior, 11(6), 717-726, 1972). These benefits can occur through several encoding mechanisms, one of which may be event segmentation. Event segmentation is one's ability to parse information into meaningful units as an activity unfolds. The current experiment evaluated whether two top-down manipulations-providing context or perspective taking-influence the segmentation and memory of text. For the ambiguous texts in Experiment 1, half the participants received context in the form of a title, whereas the other half received no context. For the text in Experiment 2, half the participants read from the perspective of a burglar and the other half read from the perspective of a home buyer. In both experiments, participants read the passages, recalled the information, and then segmented the passages into meaningful units. Consistent with previous findings, participants who received context recalled more information compared with those who received no context, and participants in one perspective were more likely to recall information relevant to their perspective. Most importantly, we found that context and perspective facilitated more normative segmentation; however, the differences were small and suggest that effects of top-down processing on the segmentation of text may be modest at best. Thus, event segmentation processes that operate during text comprehension are influenced by semantic knowledge but may be more heavily driven by other factors (e.g., perceptual cues).


Assuntos
Memória Episódica , Rememoração Mental/fisiologia , Leitura , Teoria da Mente/fisiologia , Adulto , Feminino , Humanos , Masculino , Semântica , Adulto Jovem
11.
J Chem Phys ; 149(4): 044501, 2018 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-30068204

RESUMO

The orientational dynamics and microscopic structures of imidazolium-based ionic liquids of varying hydrophilicity were investigated using optical heterodyne-detected optical Kerr effect (OHD-OKE) spectroscopy and atomistic simulations. Hydrophilicity was tuned via anion selection, cation alkyl chain length, and the addition of a strong hydrogen bond donor on the cation (protic ionic liquid). In the hydrophobic samples, which saturate at relatively low water concentration, OHD-OKE data display Debye Stokes Einstein (DSE) behavior as a function of water concentration. The DSE behavior indicates that the microstructures of the hydrophobic ionic liquid/water mixtures do not fundamentally change as a function of water concentration. The hydrophilic samples have two regimes of different DSE behaviors demonstrating the presence of two structural regimes depending on water concentration. These experimental results indicate that in hydrophilic ionic liquid/water samples, significant structural changes occur to accommodate high water concentrations, while hydrophobic samples become water saturated because the restructuring of local ionic structures is unfavorable. Atomistic simulations show that the local ionic microstructures experience distinct changes in these hydrophilic ionic liquid/water binary samples because of the delicate interplay of intermolecular interactions among imidazolium cations, hydrophilic anions, and water molecules.

12.
Memory ; 26(6): 771-783, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29187067

RESUMO

Judgments of learning (JOL) made after a delay more accurately predict subsequent recall than JOLs made immediately after learning. One explanation is that delayed JOLs involve retrieving information about the target item from secondary memory, whereas immediate JOLs involve retrieval from primary memory. One view of working memory claims that information in primary memory is displaced to secondary memory when attention is shifted to a secondary task. Thus, immediate JOLs might be as accurate as delayed JOLs if an intervening task displaces the target item from primary memory, requiring retrieval from secondary memory, prior to making the JOL. In four experiments, participants saw related word-pairs and made JOLs predicting later recall of the item. In Experiment 1, delayed JOLs were more accurate than JOLs made shortly after learning, regardless of whether a secondary task intervened between learning and JOL. In Experiments 2-4, the secondary task demands increased and JOLs made shortly after learning with an intervening task were just as accurate as delayed JOLs, and both were more accurate than immediate JOLs with no intervening task (Experiment 4). These results are consistent with a retrieval-based account of JOLs, and demonstrate that the "delayed-JOL effect" can be obtained without a long delay.


Assuntos
Sinais (Psicologia) , Julgamento , Rememoração Mental , Aprendizagem por Associação de Pares , Adulto , Feminino , Humanos , Masculino , Memória de Curto Prazo , Adulto Jovem
13.
J Am Soc Nephrol ; 28(3): 971-980, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27647856

RESUMO

Vascular endothelial dysfunction and increased arterial stiffness contribute to increased cardiovascular risk in patients with CKD who exhibit chronic systemic inflammation. Because chronic inflammation contributes to vascular dysfunction, blocking inflammation may reduce cardiovascular risk in patients with CKD. In a two-site, double-blind trial, we randomized 42 adult patients with stage 3-4 CKD who were already receiving optimal background therapy to receive either IL-1 trap rilonacept or placebo for 12 weeks. Coprimary end points included change in brachial artery flow-mediated dilation (FMDBA) and aortic pulse-wave velocity (aPWV) after 4, 8, and 12 weeks. Exploratory end points included change in high-sensitivity C-reactive protein (hsCRP), FMDBA after acute ascorbic acid infusion, and vascular endothelial cell protein expression of NADPH oxidase. Participants were 63±11 (mean±SD) years of age and 24% were women; mean eGFR was 38±13 ml/min per 1.73 m2 Compared with placebo, rilonacept improved FMDBA (baseline: 3.36%±2.06% [mean±SD], 12 weeks: 2.45%±2.29% with placebo and baseline: 3.75%±3.12%, 12 weeks: 4.86%±3.20% with rilonacept; P<0.01), without changing aPWV (P=0.56). Rilonacept also reduced hsCRP levels (median [interquartile range]) (baseline: 4.60 [1.90-8.22] mg/L, 12 weeks: 2.16 [0.92-7.38] mg/L; P<0.01) and endothelial cell NADPH oxidase expression (P<0.05). Acute infusion of ascorbic acid to inhibit superoxide production associated with a nonsignificant trend toward increased FMDBA in the placebo group (P=0.07) but not the rilonacept group (P=0.56). Rilonacept was well tolerated (five adverse events versus two with placebo). In conclusion, treatment with an IL-1 trap improved FMDBA without changing aPWV and reduced systemic inflammation in patients with CKD.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Inflamação/prevenção & controle , Interleucina-1/antagonistas & inibidores , Proteínas Recombinantes de Fusão/farmacologia , Proteínas Recombinantes de Fusão/uso terapêutico , Insuficiência Renal Crônica/tratamento farmacológico , Insuficiência Renal Crônica/fisiopatologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/efeitos dos fármacos , Análise de Onda de Pulso , Fluxo Sanguíneo Regional/efeitos dos fármacos , Insuficiência Renal Crônica/metabolismo
14.
J Am Chem Soc ; 139(6): 2408-2420, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28099808

RESUMO

The dynamics of the room-temperature ionic liquid (RTIL) 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BmimNTf2) were investigated with two-dimensional infrared (2D IR) vibrational echo spectroscopy and polarization selective pump-probe (PSPP) experiments. The CN stretch frequency of a modified Bmim+ cation (2-SeCN-Bmim+), in which a SeCN moiety was substituted onto the C-2 position of the imidazolium ring, was used as a vibrational probe. A major result of the 2D IR experiments is the observation of a long time scale structural spectral diffusion component of 600 ps in addition to short and intermediate time scales similar to those measured for selenocyanate anion (SeCN-) dissolved in BmimNTf2. In contrast to 2-SeCN-Bmim+, SeCN- samples its inhomogeneous line width nearly an order of magnitude faster than the complete structural randomization time of neat BmimNTf2 liquid (870 ± 20 ps) measured with optical heterodyne-detected optical Kerr effect (OHD-OKE) experiments. The orientational correlation function obtained from PSPP experiments on 2-SeCN-Bmim+ exhibits two periods of restricted angular diffusion (wobbling-in-a-cone) followed by complete orientational randomization on a time scale of 900 ± 20 ps, significantly slower than observed for SeCN- but identical within experimental error to the complete structural randomization time of BmimNTf2. The experiments indicate that 2-SeCN-Bmim+ is sensitive to local motions of the ionic region that influence the spectral diffusion and reorientation of small, anionic, and neutral molecules as well as significantly slower, longer-range fluctuations that are responsible for complete randomization of the liquid structure.

15.
Curr Opin Infect Dis ; 30(1): 93-100, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27755143

RESUMO

PURPOSE OF REVIEW: Eastern Europe and Central Asia (EECA) has experienced large-scale epidemics of syphilis, hepatitis C virus (HCV) and HIV over the past few decades. Here, we review recent evidence on the epidemiology of and the response to these intersecting epidemics. RECENT FINDINGS: The HIV epidemic in EECA continues to expand, with new infections increasing by more than 50% between 2010 and 2015. HCV is now in the top 10 causes of death in EECA, with Russia accounting for more than half of the global burden of HCV infections, but access to direct-acting antivirals remains a major obstacle for control of the epidemic. Although syphilis incidence is generally declining, high prevalence is reported in key populations, particularly sex workers and people who inject drugs. Recent epidemiological studies have highlighted very high prevalence of HIV, syphilis and HCV in prison populations, alongside poor access to prevention and treatment. SUMMARY: Multiple factors are contributing to the ongoing and overlapping HIV, HCV and syphilis epidemics in EECA, including low coverage with antiretroviral therapy and insufficient scale of prevention services. Further research is required to estimate the burden of infections and identify effective prevention and treatment strategies in hard-to-reach key populations, particularly men who have sex with men.


Assuntos
Infecções por HIV/epidemiologia , Hepatite C/epidemiologia , Sífilis/epidemiologia , Europa Oriental/epidemiologia , Feminino , Hepacivirus , Humanos , Incidência , Masculino , Prevalência , Minorias Sexuais e de Gênero
16.
Clin Nephrol ; 88(9): 132-143, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28699886

RESUMO

OBJECTIVE: Epidemiologic studies have suggested a link between chronic systemic inflammation and chronic kidney disease-mineral and bone disorder (CKD-MBD). Additionally, declining renal function is associated with worsening physical and cognitive function, which may potentially be explained by systemic inflammation, CKD-MBD, or both. We hypothesized that inhibiting inflammation with an interleukin-1 (IL-1) trap would improve markers of CKD-MBD as well as physical/cognitive function in patients with moderate-to-severe CKD. METHODS: In a two-site, double-blind trial, 39 patients with stage 3 - 4 CKD completed a randomized trial receiving either the IL-1 trap rilonacept (160 mg/week) or placebo for 12 weeks. The following CKD-MBD markers were assessed in serum before and after the intervention: calcium, phosphorus, 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, 24,25-dihydroxyvitamin D, intact parathyroid hormone (iPTH), and fibroblast growth factor 23 (FGF23). A battery of tests was also administered in a subgroup (n = 23) to assess multiple domains of physical function (endurance, locomotion, dexterity, balance, strength, and fatigue) and cognitive function. RESULTS: Participants were 65 ± 10 years of age, 23% female, and had a mean estimated glomerular filtration rate of 38 ± 13 mL/min/1.73m2. There were no changes in serum calcium, phosphorus, any vitamin D metabolite, iPTH, or FGF23 levels (p ≥ 0.28) with IL-1 inhibition. Similarly, rilonacept did not alter locomotion, dexterity, balance, strength, fatigue, or cognitive function (p ≥ 0.13). However, endurance (400-m walk time) tended to improve in the rilonacept (-31 s) vs. placebo group (-2 s; p = 0.07). CONCLUSIONS: In conclusion, 12 weeks of IL-1 inhibition did not improve markers of CKD-MBD or physical function.
.


Assuntos
Distúrbio Mineral e Ósseo na Doença Renal Crônica/tratamento farmacológico , Interleucina-1/antagonistas & inibidores , Proteínas Recombinantes de Fusão/uso terapêutico , Idoso , Distúrbio Mineral e Ósseo na Doença Renal Crônica/sangue , Distúrbio Mineral e Ósseo na Doença Renal Crônica/fisiopatologia , Método Duplo-Cego , Feminino , Fator de Crescimento de Fibroblastos 23 , Fatores de Crescimento de Fibroblastos/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Vitamina D/análogos & derivados , Vitamina D/sangue
17.
J Chem Phys ; 147(19): 194502, 2017 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-29166092

RESUMO

The structural dynamics of a series of 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (CnmimNTf2, n = 2, 4, 6, 10: ethyl-Emim; butyl-Bmim; hexyl-Hmim; decyl-Dmim) room temperature ionic liquids confined in the pores of polyether sulfone (PES 200) membranes with an average pore size of ∼350 nm and in the bulk liquids were studied. Time correlated single photon counting measurements of the fluorescence of the fluorophore coumarin 153 (C153) were used to observe the time-dependent Stokes shift (solvation dynamics). The solvation dynamics of C153 in the ionic liquids are multiexponential decays. The multiexponential functional form of the decays was confirmed as the slowest decay component of each bulk liquid matches the slowest component of the liquid dynamics measured by optical heterodyne-detected optical Kerr effect (OHD-OKE) experiments, which is single exponential. The fact that the slowest component of the Stokes shift matches the OHD-OKE data in all four liquids identifies this component of the solvation dynamics as arising from the complete structural randomization of the liquids. Although the pores in the PES membranes are large, confinement on the mesoscopic length scale results in substantial slowing of the dynamics, a factor of ∼4, for EmimNTf2, with the effect decreasing as the chain length increases. By DmimNTf2, the dynamics are virtually indistinguishable from those in the bulk liquid. The rotation relaxation of C153 in the four bulk liquids was also measured and showed strong coupling between the C153 probe and its environment.

18.
Mem Cognit ; 45(6): 940-955, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28653273

RESUMO

Readers generate situation models representing described events, but the nature of these representations may differ depending on the reading goals. We assessed whether instructions to pay attention to different situational dimensions affect how individuals structure their situation models (Exp. 1) and how they update these models when situations change (Exp. 2). In Experiment 1, participants read and segmented narrative texts into events. Some readers were oriented to pay specific attention to characters or space. Sentences containing character or spatial-location changes were perceived as event boundaries-particularly if the reader was oriented to characters or space, respectively. In Experiment 2, participants read narratives and responded to recognition probes throughout the texts. Readers who were oriented to the spatial dimension were more likely to update their situation models at spatial changes; all readers tracked the character dimension. The results from both experiments indicated that attention to individual situational dimensions influences how readers segment and update their situation models. More broadly, the results provide evidence for a global situation model updating mechanism that serves to set up new models at important narrative changes.


Assuntos
Atenção/fisiologia , Compreensão/fisiologia , Narração , Leitura , Adulto , Humanos , Adulto Jovem
19.
AIDS Behav ; 20(1): 174-83, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26054389

RESUMO

Ukraine has one of the largest populations of persons living with HIV in Europe. Data on 2019 HIV-positive married or cohabiting women enrolled in a postnatal cohort from 2007 to 2012 were analysed to investigate prevalence and factors associated with self-reported non-disclosure of HIV status. Median age at enrolment was 27.5 years, with two-thirds diagnosed during their most recent pregnancy. Almost all had received antenatal antiretroviral therapy and 24 % were taking it currently. One-tenth (n = 198) had not disclosed their HIV status to their partner and 1 in 20 (n = 93) had disclosed to no-one. Factors associated with non-disclosure were: unmarried status (AOR 2.99 (95 % CI 1.51-5.92), younger age at leaving full-time education (AOR 0.41 (95 % CI 0.19-0.88) for ≥19 years vs ≤16 years) and lack of knowledge of partner's HIV status (AOR 2.01 (95 % CI 1.09-3.66). Further work is needed to support disclosure in some groups and to explore relationships between disclosure and psychological factors in this setting, including depression, lack of support and perception of stigma.


Assuntos
Infecções por HIV/psicologia , Autorrevelação , Parceiros Sexuais/psicologia , Estigma Social , Revelação da Verdade , Adolescente , Adulto , Estudos de Coortes , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/etnologia , Humanos , Gravidez , Prevalência , Autorrelato , Fatores Socioeconômicos , Ucrânia/epidemiologia , Adulto Jovem
20.
BMC Infect Dis ; 16(1): 755, 2016 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-27955711

RESUMO

BACKGROUND: Ukraine's injecting drug use-driven HIV epidemic is among the most severe in Europe with high burden of HCV co-infection. HIV/HCV co-infected individuals are at elevated risk of HCV-related morbidity, but little is known about burden of liver disease and associated factors in the HIV-positive population in Ukraine, particularly among women. METHODS: Characteristics of 2050 HIV-positive women enrolled into the Ukrainian Study of HIV-infected Childbearing Women were described by HCV serostatus. Aspartate transaminase (AST) to platelet ratio (APRI) and FIB-4 scores were calculated and exact logistic regression models fitted to investigate factors associated with significant fibrosis (APRI >1.5) among 762 women with an APRI score available. RESULTS: Of 2050 HIV-positive women (median age 27.7 years, IQR 24.6-31.3), 33% were HCV co-infected (79% of those with a history of injecting drug use vs 23% without) and 17% HBsAg positive. A quarter were on antiretroviral therapy at postnatal cohort enrolment. 1% of the HIV/HCV co-infected group had ever received treatment for HCV. Overall, 24% had an alanine aminotransferase level >41 U/L and 34% an elevated AST (53% and 61% among HIV/HCV co-infected). Prevalence of significant fibrosis was 4.5%; 2.5% among 445 HIV mono-infected and 12.3% among 171 HIV/HCV co-infected women. 1.2% had a FIB-4 score >3.25 indicating advanced fibrosis. HCV RNA testing in a sub-group of 56 HIV/HCV co-infected women indicated a likely spontaneous clearance rate of 18% and predominance of HCV genotype 1, with one-third having genotype 3 infection. Factors associated with significant fibrosis were HCV co-infection (AOR 2.53 95%CI 1.03-6.23), history of injecting drug use (AOR 3.51 95%CI 1.39-8.89), WHO stage 3-4 HIV disease (AOR 3.47 95%CI 1.51-7.99 vs stage 1-2 HIV disease) and not being on combination antiretroviral therapy (AOR 3.08 95%CI 1.23-7.74), adjusted additionally for HBV co-infection, smoking and age. CONCLUSIONS: Most HIV/HCV co-infected women had elevated liver enzymes and 12% had significant fibrosis according to APRI. Risk factors for liver fibrosis in this young HIV-positive population include poorly controlled HIV and high burden of HCV. Results highlight the importance of addressing modifiable risk factors and rolling out HCV treatment to improve the health outcomes of this group.


Assuntos
Antivirais/uso terapêutico , Biomarcadores/análise , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Infecções por HIV/complicações , Hepatite C/tratamento farmacológico , Cirrose Hepática/etiologia , Adulto , Fatores Etários , Antirretrovirais/uso terapêutico , Antivirais/efeitos adversos , Aspartato Aminotransferases/análise , Plaquetas/citologia , Plaquetas/metabolismo , Estudos de Coortes , Coinfecção/epidemiologia , Feminino , Genótipo , Infecções por HIV/tratamento farmacológico , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C/complicações , Hepatite C/epidemiologia , Humanos , Modelos Logísticos , Razão de Chances , Prevalência , Fatores de Risco , Fumar , Ucrânia/epidemiologia , Carga Viral , Adulto Jovem
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