Your browser doesn't support javascript.
loading
: 20 | 50 | 100
1 - 20 de 232
1.
Nature ; 625(7996): 760-767, 2024 Jan.
Article En | MEDLINE | ID: mdl-38092039

GDF15, a hormone acting on the brainstem, has been implicated in the nausea and vomiting of pregnancy, including its most severe form, hyperemesis gravidarum (HG), but a full mechanistic understanding is lacking1-4. Here we report that fetal production of GDF15 and maternal sensitivity to it both contribute substantially to the risk of HG. We confirmed that higher GDF15 levels in maternal blood are associated with vomiting in pregnancy and HG. Using mass spectrometry to detect a naturally labelled GDF15 variant, we demonstrate that the vast majority of GDF15 in the maternal plasma is derived from the feto-placental unit. By studying carriers of rare and common genetic variants, we found that low levels of GDF15 in the non-pregnant state increase the risk of developing HG. Conversely, women with ß-thalassaemia, a condition in which GDF15 levels are chronically high5, report very low levels of nausea and vomiting of pregnancy. In mice, the acute food intake response to a bolus of GDF15 is influenced bi-directionally by prior levels of circulating GDF15 in a manner suggesting that this system is susceptible to desensitization. Our findings support a putative causal role for fetally derived GDF15 in the nausea and vomiting of human pregnancy, with maternal sensitivity, at least partly determined by prepregnancy exposure to the hormone, being a major influence on its severity. They also suggest mechanism-based approaches to the treatment and prevention of HG.


Growth Differentiation Factor 15 , Hyperemesis Gravidarum , Nausea , Vomiting , Animals , Female , Humans , Mice , Pregnancy , beta-Thalassemia/blood , beta-Thalassemia/metabolism , Fetus/metabolism , Growth Differentiation Factor 15/blood , Growth Differentiation Factor 15/metabolism , Hormones/blood , Hormones/metabolism , Hyperemesis Gravidarum/complications , Hyperemesis Gravidarum/metabolism , Hyperemesis Gravidarum/prevention & control , Hyperemesis Gravidarum/therapy , Nausea/blood , Nausea/complications , Nausea/metabolism , Placenta/metabolism , Vomiting/blood , Vomiting/complications , Vomiting/metabolism
3.
Nature ; 599(7885): 436-441, 2021 11.
Article En | MEDLINE | ID: mdl-34732894

The state of somatic energy stores in metazoans is communicated to the brain, which regulates key aspects of behaviour, growth, nutrient partitioning and development1. The central melanocortin system acts through melanocortin 4 receptor (MC4R) to control appetite, food intake and energy expenditure2. Here we present evidence that MC3R regulates the timing of sexual maturation, the rate of linear growth and the accrual of lean mass, which are all energy-sensitive processes. We found that humans who carry loss-of-function mutations in MC3R, including a rare homozygote individual, have a later onset of puberty. Consistent with previous findings in mice, they also had reduced linear growth, lean mass and circulating levels of IGF1. Mice lacking Mc3r had delayed sexual maturation and an insensitivity of reproductive cycle length to nutritional perturbation. The expression of Mc3r is enriched in hypothalamic neurons that control reproduction and growth, and expression increases during postnatal development in a manner that is consistent with a role in the regulation of sexual maturation. These findings suggest a bifurcating model of nutrient sensing by the central melanocortin pathway with signalling through MC4R controlling the acquisition and retention of calories, whereas signalling through MC3R primarily regulates the disposition of calories into growth, lean mass and the timing of sexual maturation.


Child Development/physiology , Nutritional Status/physiology , Puberty/physiology , Receptor, Melanocortin, Type 3/metabolism , Sexual Maturation/physiology , Adolescent , Aged, 80 and over , Animals , Child , Estrous Cycle/genetics , Estrous Cycle/physiology , Female , Homozygote , Humans , Hypothalamus/cytology , Hypothalamus/physiology , Insulin-Like Growth Factor I/metabolism , Male , Melanocortins/metabolism , Menarche/genetics , Menarche/physiology , Mice , Phenotype , Puberty/genetics , Receptor, Melanocortin, Type 3/deficiency , Receptor, Melanocortin, Type 3/genetics , Sexual Maturation/genetics , Time Factors , Weight Gain
4.
Parkinsonism Relat Disord ; 82: 128-132, 2021 01.
Article En | MEDLINE | ID: mdl-33321452

INTRODUCTION: In 2019, we published the results of a Phase IIb randomized controlled trial of putaminal encapsulated porcine choroid plexus cell (termed NTCELL®) administration in patients with Parkinson's disease. This study failed to meet its primary efficacy end-point of a change in UPDRS part III score in the 'off' state at 26-weeks post-implant. However, a number of secondary end-points reached statistical significance. We questioned whether with longer follow-up, clinically significant improvements would be observed. For this reason, we decided to follow-up all patients periodically to week 104. Herein, we report the results of this long-term follow-up. METHODS: All 18 patients included in the original study were periodically re-assessed at weeks 52, 78 and 104 post-implant. At each time-point, motor and non-motor function, quality of life and levodopa equivalent daily dose was assessed using a standardized testing battery. RESULTS: At week 104, no significant differences in UPDRS part III scores in the 'off' state were observed in any of the treatment groups compared to baseline. Only a single serious adverse event - hospitalisation due to Parkinson's disease rigidity not responding to changes in medications - was considered potentially related to the implant procedure. There was no evidence of xenogeneic viral transmission. CONCLUSION: Un-blinded, long-duration follow-up to week 104 post-implantation showed no evidence that putaminal NTCELL® administration produces significant clinical benefit in patients with moderately advanced Parkinson's disease.


Alginates , Choroid Plexus/cytology , Outcome Assessment, Health Care , Parkinson Disease/therapy , Putamen , Transplantation, Heterologous/adverse effects , Aged , Animals , Capsules/therapeutic use , Female , Follow-Up Studies , Humans , Male , Middle Aged , Parkinson Disease/surgery , Putamen/surgery , Swine
5.
Scientifica (Cairo) ; 2018: 9120942, 2018.
Article En | MEDLINE | ID: mdl-29623233

Two types of lipase, Candida rugosa lipase (CRL) and porcine pancreas lipase (PPL), were used to hydrolyze virgin coconut oil (VCO). The hydrolysis process was carried out under four parameters, VCO to buffer ratio, lipase concentration, pH, and temperature, which have a significant effect on hydrolysis of lipase. CRL obtained the best hydrolysis condition at 1 : 5 of VCO to buffer ratio, 1.5% of CRL concentration, pH 7, and temperature of 40°C. Meanwhile, PPL gave different results at 1 : 4 of VCO to buffer ratio, 2% of lipase concentration, pH 7.5, and 40°C. The highest hydrolysis degree of CRL and PPL was obtained after 16 hours and 26 hours, reaching 79.64% and 27.94%, respectively. Besides, the hydrolysis process was controlled at different time course (every half an hour) at the first 4 hours of reaction to compare the initial hydrolysis degree of these two lipase types. FFAs from hydrolyzed products were isolated and determined the percentage of each fatty acid which contributes to the FFAs mixture. As a result, medium chain fatty acids (MCFAs) made up the main contribution in composition of FFAs and lauric acid (C12) was the largest segment (47.23% for CRL and 44.23% for PPL).

6.
Rev Sci Instrum ; 88(8): 084101, 2017 Aug.
Article En | MEDLINE | ID: mdl-28863635

We present an instrument for measuring pressure changes and heat flows of physical and chemical processes occurring in gram-scale solid samples under high pressures of reactive gases. Operation is demonstrated at 1232 °C under 33 bars of pure hydrogen. Calorimetric heat flow is inferred using a grey-box non-linear lumped-element heat transfer model of the instrument. Using an electrical calibration heater to deliver 900 J/1 W pulses at the sample position, we demonstrate a dynamic calorimetric power resolution of 50 mW when an 80-s moving average is applied to the signal. Integration of the power signal showed that the 900 J pulse energy could be measured with an average accuracy of 6.35% or better over the temperature range 150-1100 °C. This instrument is appropriate for the study of high-temperature metal hydride materials for thermochemical energy storage.

7.
Eur J Clin Microbiol Infect Dis ; 36(7): 1213-1216, 2017 Jul.
Article En | MEDLINE | ID: mdl-28155015

Nitrofurantoin remains a key oral antibiotic stewardship program (ASP) option in the treatment of acute uncomplicated cystitis (AUC) due to multi-drug resistant (MDR) Gram negative bacilli (GNB). However, there have been concerns regarding decreased nitrofurantoin efficacy with renal insufficiency. In our experience over the past three decades, nitrofurantoin has been safe and effective in treating AUC in hospitalized adults with renal insufficiency. Accordingly, we retrospectively reviewed our recent experience treating AUC in hospitalized adults with decreased renal function (CrCl < 60 ml/min) with nitrofurantoin. Excluded were complicated urinary tract infections. Urinary isolated susceptibility testing was done by micro broth dilution (MBD). Treatment duration was 5-7 days. Cure was defined as eradication of the uropathogen and failure was defined as minimal/no decrease in urine colony counts. Of 26 evaluable patients with renal insufficiency (CrCl < 60 ml/min), nitrofurantoin eradicated the uropathogen in 18/26 (69%) of patients, and failed in 8/26 (31%). Of the eight failures, five were due to intrinsically resistant uropathogens, e.g., Proteus sp., and one failure was related to an alkaline urine. Of the treatment failures, only two were due to renal insufficiency, i.e., CrCl < 30 ml/min. Since there are few oral antibiotics available to treat AUC due to MDR GNB uropathogens, these results have important ASP implications. Currently, nitfurantoin is not recommended if CrCl < 60 ml/min. In our experience, used appropriately against susceptible uropathogens, nitrofurantoin was highly effective in nearly all patients with CrCl = 30-60 ml/min., and only failed in two patients due to renal insufficiency (CrCl < 30 ml/ml).


Anti-Infective Agents, Urinary/adverse effects , Anti-Infective Agents, Urinary/therapeutic use , Cystitis/drug therapy , Gram-Negative Bacterial Infections/drug therapy , Nitrofurantoin/adverse effects , Nitrofurantoin/therapeutic use , Renal Insufficiency/complications , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Retrospective Studies , Treatment Outcome
8.
Eye (Lond) ; 31(1): 113-118, 2017 Jan.
Article En | MEDLINE | ID: mdl-27636230

PurposeTo determine the differences in the presentation of ophthalmic giant cell arteritis between African-Americans and Caucasians.MethodsThis was a multicenter retrospective case series comparing African-American patients with ophthalmic GCA to a previously published Caucasian cohort. Neuro-ophthalmic centers across the United States were contacted to provide data on African-American patients with biopsy-proven ophthalmic giant cell arteritis. The differences between African-American and Caucasian patients with respect to multiple variables, including age, sex, systemic and ophthalmic signs and symptoms, ocular ischemic lesions, and laboratory results were studied.ResultsThe Caucasian cohort was slightly older (mean=76.1 years) than the African-American cohort (mean=72.6 years, P=0.03), and there was no difference in sex distribution between the two cohorts. Headache, neck pain, and anemia were more frequent, while jaw claudication was less frequent in African-Americans (P<0.01, <0.001, 0.02, and 0.03 respectively). Acute vision loss was the most common presentation of giant cell arteritis in both groups, though it was less common in African-Americans (78 vs 98% of Caucasians, P<0.001). Eye pain was more common in African-Americans (28 vs 8% of Caucasians, P<0.01).ConclusionsThe presenting features of ophthalmic giant cell arteritis in African-Americans and Caucasians are not markedly different, although a few significant differences exist, including higher rates of headache, neck pain, anemia, and eye pain, and lower rates of jaw claudication and acute vision loss in African-Americans. Persons presenting with suspicious signs and symptoms should undergo evaluation for giant cell arteritis regardless of race.


Black or African American/statistics & numerical data , Eye Pain/epidemiology , Giant Cell Arteritis/complications , Vision Disorders/epidemiology , Aged , Aged, 80 and over , Eye Pain/etiology , Female , Giant Cell Arteritis/epidemiology , Giant Cell Arteritis/physiopathology , Humans , Male , Middle Aged , Retrospective Studies , Sex Distribution , Temporal Arteries/pathology , United States/epidemiology , Vision Disorders/etiology , Visual Acuity/physiology , White People/statistics & numerical data
9.
AJNR Am J Neuroradiol ; 37(10): 1957-1963, 2016 Oct.
Article En | MEDLINE | ID: mdl-27282859

BACKGROUND AND PURPOSE: Automated methods for quantitation of tissue and CSF volumes by MR imaging are available for the cranial but not the spinal compartment. We developed an iterative method for delineation of the spinal CSF spaces for automated measurements of CSF and cord volumes and applied it to study craniospinal CSF redistribution following lumbar withdrawal in patients with idiopathic intracranial hypertension. MATERIALS AND METHODS: MR imaging data were obtained from 2 healthy subjects and 8 patients with idiopathic intracranial hypertension who were scanned before, immediately after, and 2 weeks after diagnostic lumbar puncture. Imaging included T1-weighted and T2-weighted sequences of the brain and T2-weighted scans of the spine. Repeat scans in 4 subjects were used to assess measurement reproducibility. Whole CNS CSF volumes measured prior to and following lumbar puncture were compared with the withdrawn amounts of CSF. RESULTS: CSF and cord volume measurements were highly reproducible with mean variabilities of -0.7% ± 1.4% and -0.7% ± 1.0%, respectively. Mean spinal CSF volume was 77.5 ± 8.4 mL. The imaging-based pre- to post-CSF volume differences were consistently smaller and strongly correlated with the amounts removed (R = 0.86, P = .006), primarily from the lumbosacral region. These differences are explained by net CSF formation of 0.41 ± 0.18 mL/min between withdrawal and imaging. CONCLUSIONS: Automated measurements of the craniospinal CSF redistribution following lumbar withdrawal in idiopathic intracranial hypertension reveal that the drop in intracranial pressure following lumbar puncture is primarily related to the increase in spinal compliance and not cranial compliance due to the reduced spinal CSF volume and the nearly unchanged cranial CSF volume.

10.
J Viral Hepat ; 23(1): 53-61, 2016 Jan.
Article En | MEDLINE | ID: mdl-26289820

Hepatocellular carcinoma (HCC) is the most common complication of HCV infection leading to liver transplantation. We evaluated the impact of aetiology of liver disease on patient and graft survival following liver transplantation for HCC. From the Scientific Registry of Transplant Recipients (2002-2011), all adults who underwent liver transplantation for HCC were retrospectively included. Aetiology of liver disease was grouped into HCV, HBV, HCV-HBV co-infection and nonviral liver disease. Of 8,733 liver transplant recipients with HCC, 5507 had HCV, 631 had HBV, 163 were co-infected, and 2432 had nonviral causes of liver disease. In follow-up (48 ± 32 months), 8.2% had graft failure and 29.5% died. The mean rates of graft failure were 9.5%, 4.7%, 6.1% and 6.4% in HCV, HBV, HCV-HBV co-infection and nonviral liver disease, respectively (P < 0.0001). Post-transplant mortality rate in patients with HBV was 20.2%, HCV 31.0%, HCV-HBV 28.5% and nonviral 28.5% (P < 0.0001). This difference was significant starting one year post-transplant and became even more prominent later in follow-up. Five-year post-transplant survival was 64.7% in HCV, 77.7% in HBV, 71.0% in HCV-HBV and 69.1% in nonviral HCC (P < 0.0001). A diagnosis of HCV in patients with HCC was also independently associated with an increased risk of both graft failure (adjusted hazard ratio = 1.84 (1.46-2.33), P < 0.0001) and mortality (1.35 (1.21-1.50), P < 0.0001) in multivariate analysis. Patients with HCV-related HCC are at higher risk of adverse post-transplant outcomes. These patients should be considered for preemptive interferon-free antiviral therapy prior to or immediately following liver transplantation.


Carcinoma, Hepatocellular/surgery , Hepatitis C, Chronic/surgery , Liver Neoplasms/surgery , Liver Transplantation/mortality , Antiviral Agents/therapeutic use , Carcinoma, Hepatocellular/mortality , Carcinoma, Hepatocellular/virology , Coinfection/pathology , Coinfection/virology , Female , Graft Survival , Hepatitis B, Chronic/drug therapy , Hepatitis B, Chronic/pathology , Hepatitis B, Chronic/virology , Hepatitis C, Chronic/drug therapy , Hepatitis C, Chronic/pathology , Hepatitis C, Chronic/virology , Humans , Liver Neoplasms/mortality , Liver Neoplasms/virology , Male , Middle Aged , Retrospective Studies , Transplant Recipients/statistics & numerical data
11.
Transl Psychiatry ; 5: e669, 2015 Nov 03.
Article En | MEDLINE | ID: mdl-26529422

Prior studies have established that schizotypal personality traits (schizotypy) were associated with antisocial behavior (crime), but it is unclear what neural factors mediate this relationship. This study assessed the mediating effect that sub-regional prefrontal gray, specifically the orbitofrontal gray matter volume, has on the schizotypy-antisocial behavior relationship. Five prefrontal sub-regional (superior, middle, inferior, orbitofrontal and rectal gyral) gray matter volumes were assessed using structural magnetic resonance imaging in 90 adults from the community, together with schizotypy and antisocial behavior. Among all five prefrontal sub-regions, the orbitofrontal cortex (OFC) was the major region-of-interest in the present study. Mediation analyses showed that orbitofrontal gray fully mediated the association between schizotypy and antisocial behavior. After having controlled the sex, age, socio-economic statuses, whole brain volumes and substance abuse/dependence of test subjects, the orbitofrontal gray still significantly mediated the effect of schizotypy on antisocial behavior by 53.5%. These findings are the first that document a neural mediator of the schizotypy-antisocial behavior relationship. Findings also suggest that functions subserved by the OFC, including impulse control and inhibition, emotion processing and decision-making, may contribute to the above comorbidity.


Brain Mapping , Magnetic Resonance Imaging , Adult , Antisocial Personality Disorder/complications , Antisocial Personality Disorder/physiopathology , Brain/physiopathology , Female , Humans , Image Processing, Computer-Assisted , Male , Middle Aged , Schizotypal Personality Disorder/complications , Schizotypal Personality Disorder/physiopathology , Young Adult
12.
Aliment Pharmacol Ther ; 42(3): 286-95, 2015 Aug.
Article En | MEDLINE | ID: mdl-26059536

BACKGROUND: Interferon and ribavirin negatively impact health-related quality of life (HRQL) during treatment. AIM: To compare the impact of interferon and/or ribavirin-containing regimens on HRQL to interferon- and ribavirin-free regimens. METHODS: HRQL data from nine multinational phase 3 clinical trials of sofosbuvir (SOF)-based regimens with and without ledipasvir (LDV), pegylated interferon (IFN) or ribavirin (RBV) were used. The Short Form-36 (SF-36) HRQL questionnaire was administered to subjects prospectively at baseline, during treatment, and 12 and 24 weeks after treatment cessation. RESULTS: A total of 3460 CH-C with SF-36 data were included (52.2 ± 10.3 years, 62.6% male, 73.6% treatment-naïve, 15.0% cirrhotic, 68.2% HCV genotype 1 and 20.1% genotype 3). Compared to baseline HRQL, at the end of treatment, severe HRQL decrements were noted in IFN + RBV ± SOF regimens (on average, -3.8 to -24.3 on a 0-100 scale for different HRQL domains), while moderate decrements were noted in SOF + RBV ± LDV (-2.8 to -8.6). In contrast, in SOF/LDV without RBV, HRQL improvements were noted during treatment (+2.3 to +5.2). By 12 weeks post-treatment, HRQL returned to baseline in IFN + RBV ± SOF (P > 0.05) and improved in all IFN-free arms (+2.6 to +7.8). In multivariate analysis, a lower end of treatment HRQL was associated with IFN + RBV + SOF and a higher end of treatment HRQL was associated with SOF/LDV. By post-treatment-12, SOF/LDV was additionally associated with higher mental health scores. These improvements in HRQL scores were maintained 24 weeks post-treatment. CONCLUSIONS: Removing interferon and ribavirin has led to substantial improvement of health-related quality of life during treatment. This may result in better patient experience and higher adherence to treatment regimen.


Antiviral Agents/therapeutic use , Hepatitis C, Chronic/drug therapy , Interferons/therapeutic use , Ribavirin/therapeutic use , Adult , Clinical Trials, Phase III as Topic , Drug Therapy, Combination , Female , Genotype , Hepacivirus/genetics , Humans , Male , Mental Health , Middle Aged , Prospective Studies , Quality of Life , Sofosbuvir/therapeutic use , Surveys and Questionnaires , Withholding Treatment
14.
Phys Rev Lett ; 112(3): 034802, 2014 Jan 24.
Article En | MEDLINE | ID: mdl-24484144

A novel scheme for the focusing of high-energy leptons in future linear colliders was proposed in 2001 [P. Raimondi and A. Seryi, Phys. Rev. Lett. 86, 3779 (2001)]. This scheme has many advantageous properties over previously studied focusing schemes, including being significantly shorter for a given energy and having a significantly better energy bandwidth. Experimental results from the ATF2 accelerator at KEK are presented that validate the operating principle of such a scheme by demonstrating the demagnification of a 1.3 GeV electron beam down to below 65 nm in height using an energy-scaled version of the compact focusing optics designed for the ILC collider.

15.
J Thorac Cardiovasc Surg ; 146(6): 1418-23; discussion 1423-5, 2013 Dec.
Article En | MEDLINE | ID: mdl-24075470

BACKGROUND: Mitral annuloplasty with either a partial band or complete ring is an integral part of mitral valve repair for degenerative disease. The affect of annuloplasty type on outcomes has not been well described. The objective of our study was to compare echocardiographic and functional characteristics of patients who underwent mitral repair with either a complete ring or a partial band. METHODS: We evaluated 107 patients who underwent mitral repair of myxomatous degeneration at our institution by stress echocardiography, 6-minute walk testing, and short form-36 questionnaire. These assessments were performed 4.3 ± 2.2 years following mitral repair by a single surgeon. A band was used in 65 patients (61%) and a ring in 42 patients (39%). Parametric and nonparametric tests were used in the analyses. RESULTS: The labeled band and ring size used for repair were 30.7 ± 2.8 mm and 30.4 ± 2.1 mm, respectively (P = .6). The resting mean mitral gradient and valve area were 3.7 ± 1.9 mm Hg and 2.3 ± 0.6 cm(2) for patients who received a band and 5.8 ± 2.6 mm Hg and 1.8 ± 0.5 cm(2) for patients who received a ring (both P < .001). Distance traversed on 6-minute walk testing was 471 ± 77 m in the band group and 443 ± 107 m in the ring group (P = .1). At peak exercise, the mean mitral gradient (15.3 ± 8.2 mm Hg vs 10.6 ± 4.8 mm Hg; P < .001) and right ventricular systolic pressure (52.6 ± 14.2 mm Hg vs 45.8 ± 9.5 mm Hg; P = .004) were higher for patients who received a ring versus a band. Ring patients reported lower levels of energy (P = .02) and general health (P = .007) on short form-36 assessment. CONCLUSIONS: Annuloplasty using a complete ring may be associated with a higher mitral valve gradient at rest and at peak exercise in certain patients. These patients may also have worse quality of life. In view of these findings, we recommend careful consideration of annuloplasty type and size at the time of mitral repair of organic disease.


Heart Valve Prosthesis Implantation/adverse effects , Mitral Valve Annuloplasty/adverse effects , Mitral Valve Insufficiency/surgery , Mitral Valve Stenosis/diagnosis , Mitral Valve/surgery , Aged , Biomarkers/blood , Chi-Square Distribution , Cross-Sectional Studies , Echocardiography, Stress , Exercise Test , Exercise Tolerance , Female , Heart Valve Prosthesis , Heart Valve Prosthesis Implantation/instrumentation , Humans , Male , Middle Aged , Mitral Valve/diagnostic imaging , Mitral Valve/physiopathology , Mitral Valve Annuloplasty/instrumentation , Mitral Valve Insufficiency/diagnosis , Mitral Valve Insufficiency/physiopathology , Mitral Valve Stenosis/blood , Mitral Valve Stenosis/etiology , Mitral Valve Stenosis/physiopathology , Natriuretic Peptide, Brain/blood , Patient Selection , Predictive Value of Tests , Prospective Studies , Prosthesis Design , Quality of Life , Risk Factors , Surveys and Questionnaires , Systole , Treatment Outcome , Ventricular Function, Right , Ventricular Pressure
16.
J Viral Hepat ; 20(8): 550-5, 2013 Aug.
Article En | MEDLINE | ID: mdl-23808993

HCV is the leading cause of cirrhosis and liver cancer in the U.S. The Center for Disease Control (CDC) has recently recommended 'Birth Cohort Screening' of the U.S. Adult population to reduce the future burden of undiagnosed HCV infections in the U.S. Our aim was to assess independent predictors of receiving treatment in a cohort of HCV-infected patients. The Hepatitis C follow-up questionnaires of the National Health and Nutrition Examination Surveys (NHANES) conducted from 2001 to 2010 were used. The NHANES participants who tested positive for HCV RNA were followed by CDC 6 months after initial testing with questions related to their awareness of their infection and history or intention to receive treatment. A total of 500 NHANES participants tested positive for HCV RNA and were targeted for follow-up. Of these, only 203 had completed the follow-up questionnaire (response rate of 40.6%). Of these, only 101 (50%) knew about their HCV positivity before NHANES, and from them, only 34 (17%) had received treatment. In multivariate analysis, prior knowledge about their HCV infection in HCV-positive individuals was independently associated with receiving routine care from a doctor or HMO, with higher income, female gender, being in poor or fair health and not consuming excessive amounts of alcohol. On the other hand, the knowledge about HCV infection was the only independent predictor of receiving anti-HCV treatment (odds ratio 6.14). Knowledge about having HCV infection is the only independent predictor of receiving treatment. Therefore, birth cohort screening of the U.S. General population could lead to wider identification of HCV and potentially better management of the future burden of HCV and its complications.


Health Knowledge, Attitudes, Practice , Hepatitis C, Chronic/diagnosis , Hepatitis C, Chronic/drug therapy , Patient Acceptance of Health Care/statistics & numerical data , Adult , Aged , Female , Humans , Male , Middle Aged , Surveys and Questionnaires , United States
17.
AJNR Am J Neuroradiol ; 34(12): 2354-9, 2013 Dec.
Article En | MEDLINE | ID: mdl-23744692

BACKGROUND AND PURPOSE: Subjective determination of the posterior sclera flattening and optic nerve protrusion in MRI is challenging because of the 3D nature of the globe morphology. This study aims to develop and compare quantitative measures of globe flattening and optic nerve protrusion with subjective rating, and assess relationships with papilledema grade and intraocular and CSF pressures. MATERIALS AND METHODS: Data of 34 globes from 7 overweight female patients with idiopathic intracranial hypertension and 6 age- and weight-matched healthy female control subjects were assessed, as well as a subcohort of 4 of the patients with idiopathic intracranial hypertension who underwent follow-up MR imaging 2 weeks after lumbar puncture and initiation of treatment with acetazolamide. MR imaging examination included a 3D CISS sequence on 1.5T and 3T scanners with 0.6-mm isotropic resolution. Subjective ratings of globe flattening were obtained by experienced and inexperienced readers. Quantitative measures of globe flattening, nerve protrusion, and maximal deformation were derived by use of a 2D map of the distances from the globe center to the posterior wall. RESULTS: Contingency coefficients for globe flattening agreements with subjective rating by the experienced and inexperienced readers were 0.72 and 0.56, respectively. Mean values of the 3 deformation measures were significantly poorer in the idiopathic intracranial hypertension group, with nerve protrusion demonstrating the strongest difference (P = .0002). Nerve protrusion was most strongly associated with papilledema grade with a contingency coefficient of 0.74 (P = .01), whereas globe flattening was negatively correlated with intraocular pressure (R = -0.75, P < .0001). Maximal deformation was negatively associated with CSF opening pressure (R = -0.86, P = .0001). After treatment, only the changes in nerve protrusion and maximal deformation were significant. CONCLUSIONS: Automated measures of globe deformation improve reliability over subjective rating. Of the 2 globe deformation measures, nerve protrusion had the strongest predictive value for papilledema grade and had the highest sensitivity for assessment of treatment efficacy in idiopathic intracranial hypertension.


Algorithms , Image Interpretation, Computer-Assisted/methods , Intracranial Hypertension/pathology , Magnetic Resonance Imaging/methods , Optic Disk/pathology , Pattern Recognition, Automated/methods , Sclera/pathology , Adolescent , Adult , Female , Humans , Image Enhancement/methods , Reproducibility of Results , Sensitivity and Specificity , Young Adult
18.
Small GTPases ; 4(2): 78-89, 2013.
Article En | MEDLINE | ID: mdl-23354415

Cellular signaling by small GTPases is critically dependent on proper spatio-temporal orchestration of activation and output. In addition to their core G (guanine nucleotide binding)-domain, small GTPases comprise a hypervariable region (HVR) and a lipid anchor that are generally accepted to control subcellullar localization. The HVR encodes in many small GTPases a polybasic region (PBR) that permits charge-mediated association to the inner leaflet of the plasma membrane or to intracellular organelles. Over the past 15-20 years, evidence has accumulated for specific protein-protein interactions, mediated by the HVR, that control both targeting and signaling specificity of small GTPases. Using the RhoGTPase Rac1 as a paradigm we here review a series of protein partners that require the Rac1 HVR for association and that control various aspects of localized Rac1 signaling. Some of these proteins represent Rac1 activators, whereas others mediate Rac1 inactivation and degradation and yet others potentiate Rac1 downstream signaling. Finally, evidence is discussed which shows that the HVR of Rac1 also contributes to effector interactions, co-operating with the N-terminal effector domain. The complexity of localized Rac1 signaling, reviewed here, is most likely exemplary for many other small GTPases as well, representing a challenge to identify and define similar mechanisms controlling the specific signaling induced by small GTPases.


Protein Sorting Signals , Signal Transduction , rac1 GTP-Binding Protein/metabolism , Animals , Humans , Protein Interaction Domains and Motifs , Protein Transport , rac1 GTP-Binding Protein/chemistry
19.
AJNR Am J Neuroradiol ; 34(1): 29-34, 2013 Jan.
Article En | MEDLINE | ID: mdl-22766676

BACKGROUND AND PURPOSE: Impaired CSF homeostasis and altered venous hemodynamics are proposed mechanisms for elevated pressure in IIH. However, the lack of ventricular expansion steered the focus away from CSF homeostasis in IIH. This study aims to measure intracranial CSF volumes and cerebral venous drainage with MR imaging to determine whether increased CSF volume from impaired CSF homeostasis and venous hemodynamics occur in obesity-related IIH. MATERIALS AND METHODS: Two homogeneous cohorts of 11 newly diagnosed pretreatment overweight women with IIH and 11 overweight healthy women were prospectively studied. 3D volumetric MR imaging of the brain was used to quantify CSF and brain tissue volumes, and dynamic phase contrast was used to measure relative cerebral drainage through the internal jugular veins. RESULTS: Findings confirm normal ventricular volume in IIH. However, extraventricular CSF volume is significantly increased in IIH (290 ± 52 versus 220 ± 24 mL, P = .001). This is even more significant after normalization with intracranial volume (P = .0007). GM interstitial fluid volume is also increased in IIH (602 ± 57 versus 557 ± 31 mL, P = .037). Total arterial inflow is normal, but relative venous drainage through the IJV is significantly reduced in IIH (65 ± 7% versus 81 ± 10%, P = .001). CONCLUSIONS: Increased intracranial CSF volume that accumulates in the extraventricular subarachnoid space provides direct evidence for impaired CSF homeostasis in obesity-associated IIH. The finding of larger GM interstitial fluid volume is consistent with increased overall resistance to cerebral venous drainage, as evident from reduced relative cerebral drainage through the IJV. The present study confirms that both impaired CSF homeostasis and venous hemodynamics coexist in obesity-associated IIH.


Cerebrospinal Fluid/cytology , Magnetic Resonance Imaging/methods , Obesity/complications , Obesity/diagnosis , Pseudotumor Cerebri/complications , Pseudotumor Cerebri/diagnosis , Adolescent , Adult , Evidence-Based Medicine , Female , Homeostasis , Humans , Male , Middle Aged , Reproducibility of Results , Sensitivity and Specificity , Young Adult
20.
FEBS Lett ; 587(2): 111-9, 2013 Jan 16.
Article En | MEDLINE | ID: mdl-23195690

The RhoGTPase Rac1 is activated in a polarised fashion and controls cell motility. We previously showed that Rac1 binds the PP2A inhibitor SET and recruits nuclear SET to the cytosol. We show that a SET mutant, lacking a nuclear localization signal, SET(ΔNLS), promotes cell spreading and motility. This was accompanied by an increase in the number and frequency of membrane ruffles. Pharmacological inhibition of PP2A did not mimic the effects of SET(ΔNLS), however, we found that expression of SET and SET(ΔNLS) increases the levels of the MAP kinases ERK1 and ERK2.


Cell Movement/physiology , Histone Chaperones/metabolism , Transcription Factors/metabolism , Active Transport, Cell Nucleus , Base Sequence , Cell Membrane Structures/metabolism , Cytoplasm/metabolism , DNA Primers/genetics , DNA-Binding Proteins , HeLa Cells , Histone Chaperones/genetics , Humans , MAP Kinase Signaling System , Microscopy, Confocal , Mutant Proteins/genetics , Mutant Proteins/metabolism , Nuclear Localization Signals/genetics , Protein Phosphatase 2/antagonists & inhibitors , Proto-Oncogene Mas , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Transcription Factors/genetics , rac1 GTP-Binding Protein/metabolism
...