Shared genetic effects between hepatic steatosis and fibrosis: A prospective twin study.

Nonalcoholic fatty liver disease is associated with metabolic risk factors including hypertension and dyslipidemia and may progress to liver fibrosis. Studies have shown that hepatic steatosis and fibrosis are heritable, but whether they have a significant shared gene effect is unknown. This study examined the shared gene effects between hepatic steatosis and fibrosis and their associations with metabolic risk factors. This was a cross-sectional analysis of a prospective cohort of well-characterized, community-dwelling twins (45 monozygotic, 20 dizygotic twin pairs, 130 total subjects) from southern California. Hepatic steatosis was assessed with magnetic resonance imaging-proton density fat fraction and hepatic fibrosis with magnetic resonance elastography. A standard bivariate twin additive genetics and unique environment effects model was used to estimate the proportion of phenotypic variance between two phenotypes accounted for by additive genetic effects and individual-specific environmental effects. Genetic correlations estimated from this model represent the degree to which the genetic determinants of two phenotypes overlap. Mean (± standard deviation) age and body mass index were 47.1 (±21.9) years and 26.2 (±5.8) kg/m2 , respectively. Among the cohort, 20% (26/130) had hepatic steatosis (magnetic resonance imaging-proton density fat fraction ≥5%), and 8.2% (10/122) had hepatic fibrosis (magnetic resonance elastography ≥3 kPa). Blood pressure (systolic and diastolic), triglycerides, glucose, homeostatic model assessment of insulin resistance, insulin, hemoglobin A1c, and low high-density lipoprotein had significant shared gene effects with hepatic steatosis. Triglycerides, glucose, homeostatic model assessment of insulin resistance, insulin, hemoglobin A1c, and low high-density lipoprotein had significant shared gene effects with hepatic fibrosis. Hepatic steatosis and fibrosis had a highly significant shared gene effect of 0.756 (95% confidence interval 0.716-1, P < 0.0001). CONCLUSIONS: Genes involved with steatosis pathogenesis may also be involved with fibrosis pathogenesis. (Hepatology 2016;64:1547-1558).

Sitagliptin vs. placebo for non-alcoholic fatty liver disease: A randomized controlled trial.

BACKGROUND & AIMS: Uncontrolled studies show sitagliptin, an oral DPP-4 inhibitor, may improve alanine aminotransferase and liver histology in non-alcoholic fatty liver disease (NAFLD) patients. We aimed to compare sitagliptin vs. the efficacy of a placebo in reducing liver fat measured by MRI-derived proton density-fat fraction (MRI-PDFF). METHODS: This randomized, double-blind, allocation-concealed, placebo-controlled trial included 50 NAFLD patients with prediabetes or early diabetes randomized to sitagliptin orally 100mg/day or placebo for 24weeks. Primary outcome was liver fat change measured by MRI-PDFF in colocalized regions of interest within each of nine liver segments. Additional advanced assessments included MR spectroscopy (MRS) for internal validation of MRI-PDFF's accuracy, and magnetic resonance elastography (MRE) and FIBROSpect® II to assess liver fibrosis. RESULTS: Sitagliptin was not significantly better than placebo in reducing liver fat measured by MRI-PDFF (mean difference between sitagliptin and placebo arms: -1.3%, p=0.4). Compared to baseline, there were no significant differences in end-of-treatment MRI-PDFF for sitagliptin (18.1% to 16.9%, p=0.27) or placebo (16.6% to 14.0%, p=0.07). The groups had no significant differences for changes in alanine aminotransferase, aspartate aminotransferase, low-density lipoprotein, homeostatic model assessment insulin resistance, and MRE-derived liver stiffness. In both groups at baseline and post-treatment, MRI-PDFF and MRS showed robust correlation coefficients ranging from r(2)=0.96 to r(2)=0.99 (p<0.0001), demonstrating the strong internal validity of the findings. FIBROSpect® II showed no changes in the sitagliptin group but was significantly increased in the placebo group (p=0.03). CONCLUSIONS: Sitagliptin was safe but not better than placebo in reducing liver fat in prediabetic or diabetic patients with NAFLD. LAY SUMMARY: In a randomized, double-blind, placebo-controlled study, the anti-diabetic drug sitagliptin was no more effective than placebo for improving liver fat and liver fibrosis in patients with non-alcoholic fatty liver disease. This study demonstrates that non-invasive magnetic resonance imaging techniques, including magnetic resonance imaging-proton density-fat fraction and magnetic resonance elastography, can be used to assess treatment response in non-alcoholic fatty liver disease clinical trials.

Novel 3D Magnetic Resonance Elastography for the Noninvasive Diagnosis of Advanced Fibrosis in NAFLD: A Prospective Study.

OBJECTIVES: Recent studies show two-dimensional (2D)-magnetic resonance elastography (MRE) is accurate in diagnosing advanced fibrosis (stages 3 and 4) in nonalcoholic fatty liver disease (NAFLD) patients. Three-dimensional (3D)-MRE is a more advanced version of the technology that can image shear-wave fields in 3D of the entire liver. The aim of this study was to prospectively compare the diagnostic accuracy of 3D-MRE and 2D-MRE for diagnosing advanced fibrosis in patients with biopsy-proven NAFLD. METHODS: This cross-sectional analysis of a prospective study included 100 consecutive patients (56% women) with biopsy-proven NAFLD who also underwent MRE. Area under the receiver operating characteristic (AUROC) analysis was performed to assess the accuracy of 2D- and 3D-MRE in diagnosing advanced fibrosis. RESULTS: The mean (±s.d.) of age and body mass index were 50.2 (±13.6) years and 32.1 (±5.0) kg/m(2), respectively. The AUROC for diagnosing advanced fibrosis was 0.981 for 3D-MRE at 40 Hz, 0.927 for 3D-MRE at 60 Hz (standard shear-wave frequency), and 0.921 for 2D-MRE at 60 Hz (standard shear-wave frequency). At a threshold of 2.43 kPa, 3D-MRE at 40 Hz had sensitivity 1.0, specificity 0.94, positive predictive value 0.72, and negative predictive value 1.0 for diagnosing advanced fibrosis. 3D-MRE at 40 Hz had significantly higher AUROC (P<0.05) than 2D-MRE at 60 Hz for diagnosing advanced fibrosis. CONCLUSIONS: Utilizing a prospective study design, we demonstrate that 3D MRE at 40 Hz has the highest diagnostic accuracy in diagnosing NAFLD advanced fibrosis. Both 2D- and 3D-MRE at 60 Hz, the standard shear-wave frequency, are also highly accurate in diagnosing NAFLD advanced fibrosis.

Ezetimibe for the treatment of nonalcoholic steatohepatitis: assessment by novel magnetic resonance imaging and magnetic resonance elastography in a randomized trial (MOZART trial).

UNLABELLED: Ezetimibe inhibits intestinal cholesterol absorption and lowers low-density lipoprotein cholesterol. Uncontrolled studies have suggested that it reduces liver fat as estimated by ultrasound in nonalcoholic steatohepatitis (NASH). Therefore, we aimed to examine the efficacy of ezetimibe versus placebo in reducing liver fat by the magnetic resonance imaging-derived proton density-fat fraction (MRI-PDFF) and liver histology in patients with biopsy-proven NASH. In this randomized, double-blind, placebo-controlled trial, 50 patients with biopsy-proven NASH were randomized to either ezetimibe 10 mg orally daily or placebo for 24 weeks. The primary outcome was a change in liver fat as measured by MRI-PDFF in colocalized regions of interest within each of the nine liver segments. Novel assessment by two-dimensional and three-dimensional magnetic resonance elastography was also performed. Ezetimibe was not significantly better than placebo at reducing liver fat as measured by MRI-PDFF (mean difference between the ezetimibe and placebo arms -1.3%, P = 0.4). Compared to baseline, however, end-of-treatment MRI-PDFF was significantly lower in the ezetimibe arm (15%-11.6%, P < 0.016) but not in the placebo arm (18.5%-16.4%, P = 0.15). There were no significant differences in histologic response rates, serum alanine aminotransferase and aspartate aminotransferase levels, or longitudinal changes in two-dimensional and three-dimensional magnetic resonance elastography-derived liver stiffness between the ezetimibe and placebo arms. Compared to histologic nonresponders (25/35), histologic responders (10/35) had a significantly greater reduction in MRI-PDFF (-4.35 ± 4.9% versus -0.30 ± 4.1%, P < 0.019). CONCLUSIONS: Ezetimibe did not significantly reduce liver fat in NASH. This trial demonstrates the application of colocalization of MRI-PDFF-derived fat maps and magnetic resonance elastography-derived stiffness maps of the liver before and after treatment to noninvasively assess treatment response in NASH.

Ramipril for the Treatment of COVID-19: RAMIC, a Randomized, Double-Blind, Placebo-Controlled Clinical Trial.

INTRODUCTION: Retrospective studies report that angiotensin-converting enzyme inhibitors (ACEIs) may reduce the severity of COVID-19, but prospective data on de novo treatment with ACEIs are limited. The RAMIC trial was a randomized, multicenter, placebo-controlled, double-blind, allocation-concealed clinical trial to examine the efficacy of de novo ramipril versus placebo for the treatment of COVID-19. METHODS: Eligible participants were aged 18 years and older with a confirmed diagnosis of SARS-CoV-2 infection, recruited from urgent care clinics, emergency departments, and hospital inpatient wards at eight sites in the USA. Participants were randomly assigned to daily ramipril 2.5 mg or placebo orally in a 2:1 ratio, using permuted block randomization. Analyses were conducted on an intention-to-treat basis. The primary outcome was a composite of mortality, intensive care unit (ICU) admission, or invasive mechanical ventilation by day 14. RESULTS: Between 27 May 2020 and 19 April 2021, a total of 114 participants (51% female) were randomized to ramipril (n = 79) or placebo (n = 35). The overall mean (± SD) age and BMI were 45 (± 15) years and 33 (± 8) kg/m2. Two participants in the ramipril group required ICU admission and one died, compared with none in the placebo group. There were no significant differences between ramipril and placebo in the primary endpoint (ICU admission, mechanical ventilation, or death) (3% versus 0%, p = 1.00) or adverse events (27% versus 29%, p = 0.82). The study was terminated early because of a low event rate and subsequent Emergency Use Authorization of therapies for COVID-19. CONCLUSION: De novo ramipril was not different compared with placebo in improving or worsening clinical outcomes from COVID-19 but appeared safe in non-critically ill patients with COVID-19. TRIAL REGISTRATION: Clinicaltrials.gov NCT04366050.

Cerebrospinal fluid human immunodeficiency virus viral load in patients with neurosyphilis.

Syphilis is a frequent coinfection with human immunodeficiency virus (HIV). Whereas systemic syphilis infection increases plasma HIV RNA levels (viral load; VL), effects of syphilis on cerebrospinal fluid (CSF) VL are unknown. We hypothesized that intrathecal immune activation in neurosyphilis would selectively increase CSF VL in coinfected patients. In this study, HIV-infected research subjects (N = 225) were categorized into three groups based on serum rapid plasma reagin (RPR), microhemaglutination for Treponema pallidum (MHA-TP) MHA-TP, and CSF VDRL: 23 with neurosyphilis (NS+; reactive serum RPR and MHA-TP and positive CSF VDRL); 42 with systemic syphilis but not neurosyphilis (Syph+; reactive serum RPR and MHA-TP; negative CSF VDRL), and 160 without syphilis (Syph-; nonreactive serum RPR). Plasma and CSF HIV VL were quantified by reverse transcriptase-ploymerase chain reaction (RT-PCR) (Amplicor, Roche) in log(10) copies/ml. To adjust for covariates previously shown to influence CSF HIV VL (i.e., plasma VL, CD4, pleocytosis, and highly active antiretroviral therapy [HAART]), multivariable linear regression was used. Lumbar punctures (LP) done for research purposes diagnosed 23 with neurosyphilis; most (83%) of these reported prior syphilis treatment. Among subjects with detectable plasma VL, CSF VL was highest in NS+, followed by Syph+ and Syph- (P =.006). This relationship was independent of the level of plasma VL or CSF pleocytosis. By contrast, among subjects with undetectable plasma HIV VL, CSF VLs were similar in the three syphilis subgroups (P = .50). Neurosyphilis may amplify intrathecal HIV replication, possibly through immune activation that persists even after syphilis treatment. Because elevated CSF VL is associated with subsequent neurocognitive decline, future studies should evaluate the impact of neurosyphilis on the course of central nervous system (CNS) HIV infection.

Role of metabolic syndrome components in human immunodeficiency virus-associated stroke.

Metabolic syndrome (MetS) is a cluster of risk factors, including elevated mean arterial pressure (MAP), atherogenic dyslipidemia (elevated triglycerides [TRG]), abdominal obesity (increased body mass index [BMI]), glucose intolerance (elevated glucose [GLU]), and prothrombotic/inflammatory state (increases in uric acid [UA]), that are associated with increased risk of cerebrovascular disease. We studied if an association existed between MetS components and human immunodeficiency virus (HIV)-associated cryptogenic strokes-those not caused by HIV complications, endocarditis, or stimulant abuse. We performed a retrospective case-control study. Eleven cryptogenic strokes were identified from 2346 HIV-infected (HIV+) participants. Each case was matched by age, sex, and date of stroke diagnosis to five HIV+ controls without stroke. Nonparametric stratified Wilcoxon ranked sum tests with subsequent mixed effect logistic regression determined the influence of each MetS component on HIV-associated cryptogenic stroke. Although each MetS component appeared higher for HIV+ cases with cryptogenic strokes than HIV+ controls, only MAP (odds ratio [OR] = 5.70, 95% confidence interval [CI] = 1.15-28.3) and UA (OR = 1.88, 95% CI = 1.06-3.32) were statistically different. A significantly higher percentage of HIV-associated cryptogenic stroke cases met criteria for MetS (4/11 = 36%) compared to HIV+ controls (6/55 = 11%). This observational study suggests a possible role for MetS components in HIV+ cryptogenic stroke cases. Although MetS is defined as a constellation of disorders, elevated hypertension and hyperuricemia may be involved in stroke pathogenesis. Reducing MetS component levels in HIV+ patients could therefore protect them from subsequent stroke.

Craniofacial tissue regeneration: where are we?

This paper provides a brief review of adult stem cells and their potential clinical applications, specifically in craniofacial regeneration. The initial discovery of stem cells from a variety of tissues has infused tremendous research, and, in conjunction with bioengineering technologies, has potential to transform clinical dentistry.

Gut Microbiome-Based Metagenomic Signature for Non-invasive Detection of Advanced Fibrosis in Human Nonalcoholic Fatty Liver Disease.

The presence of advanced fibrosis in nonalcoholic fatty liver disease (NAFLD) is the most important predictor of liver mortality. There are limited data on the diagnostic accuracy of gut microbiota-derived signature for predicting the presence of advanced fibrosis. In this prospective study, we characterized the gut microbiome compositions using whole-genome shotgun sequencing of DNA extracted from stool samples. This study included 86 uniquely well-characterized patients with biopsy-proven NAFLD, of which 72 had mild/moderate (stage 0-2 fibrosis) NAFLD, and 14 had advanced fibrosis (stage 3 or 4 fibrosis). We identified a set of 40 features (p < 0.006), which included 37 bacterial species that were used to construct a Random Forest classifier model to distinguish mild/moderate NAFLD from advanced fibrosis. The model had a robust diagnostic accuracy (AUC 0.936) for detecting advanced fibrosis. This study provides preliminary evidence for a fecal-microbiome-derived metagenomic signature to detect advanced fibrosis in NAFLD.

Association of noninvasive quantitative decline in liver fat content on MRI with histologic response in nonalcoholic steatohepatitis.

BACKGROUND: Magnetic resonance imaging-estimated proton-density-fat-fraction (MRI-PDFF) has been shown to be a noninvasive, accurate and reproducible imaging-based biomarker for assessing steatosis and treatment response in nonalcoholic steatohepatitis (NASH) clinical trials. However, there are no data on the magnitude of MRI-PDFF reduction corresponding to histologic response in the setting of a NASH clinical trial. The aim of this study was to quantitatively compare the magnitude of MRI-PDFF reduction between histologic responders versus histologic nonresponders in NASH patients. METHODS: This study is a secondary analysis of the MOZART trial, which included 50 patients with biopsy-proven NASH randomized to ezetimibe 10 mg/day orally or placebo for 24 weeks. The primary aim was to perform a head-to-head comparative analysis of histologic responders [defined as a ⩾2-point reduction in the nonalcoholic fatty liver disease (NAFLD) Activity Score (NAS) without worsening fibrosis] versus nonresponders, and the corresponding quantitative change in liver fat content measured via MRI-PDFF. RESULTS: Of the 35 patients who underwent paired liver biopsy and MRI-PDFF assessment at the beginning and end of treatment, 10 demonstrated a histologic response. Compared with histologic nonresponders, histologic responders had a statistically significant reduction in MRI-PDFF of -4.1% ± 4.9 versus -0.6 ± 4.1 (p < 0.04) with a mean relative percent change of -29.3% ± 33.0 versus +2.0% ± 24.0 (p < 0.004), respectively. CONCLUSIONS: Utilizing paired MRI-PDFF and liver histology data, we demonstrate that a relative reduction of 29% in liver fat on MRI-PDFF is associated with a histologic response in NASH. After external validation by independent research groups, these results can be incorporated into designing future NASH clinical trials, especially those utilizing change in hepatic fat quantified by MRI-PDFF, as a treatment endpoint.

Cardiovascular risk assessment in the treatment of nonalcoholic steatohepatitis: a secondary analysis of the MOZART trial.

BACKGROUND: Nonalcoholic steatohepatitis (NASH) is associated with increased cardiovascular risk and mortality. No US Food and Drug Administration (FDA) approved therapies for NASH are available; clinical trials to date have not yet systematically assessed for changes in cardiovascular risk. This study examines the prospective utility of cardiovascular risk assessments, the Framingham risk score (FRS) and coronary artery calcium (CAC) score, as endpoints in a NASH randomized clinical trial, and assesses whether histologic improvements lead to lower cardiovascular risk. METHODS: Secondary analysis of a 24-week randomized, double-blind, placebo-controlled trial (MOZART) in which 50 biopsy-proven NASH patients received oral ezetimibe 10 mg daily (n = 25) versus placebo (n = 25). Biochemical profiling, FRS, CAC scores, liver biopsies were obtained at baseline and endpoint. RESULTS: Ezetimibe improved FRS whereas placebo did not (4.4 ± 6.2 to 2.9 ± 4.8, p = 0.038; 3.0 ± 4.4 to 2.9 ± 4.2, p = 0.794). CAC scores did not change with ezetimibe or placebo (180.4 ± 577.2 to 194.1 ± 623.9, p = 0.293; 151.4 ± 448.9 to 183.3 ± 555.7, p = 0.256). Ezetimibe improved FRS and CAC scores in more patients than placebo (48% versus 23%, p = 0.079, and 21% versus 0%, p = 0.090, respectively), though not significantly. No differences were noted in cardiovascular risk scores among histologic responders versus nonresponders. CONCLUSIONS: Ezetimibe improved FRS whereas placebo did not. FRS and CAC scores improved in a greater proportion of patients with ezetimibe; this trend did not reach significance. These findings indicate the utility and feasibility of monitoring cardiovascular risk in a NASH trial. The utility of CAC scores may be higher in trials of longer duration (⩾52 weeks) and with older patients (age ⩾45). ClinicalTrials.gov registration: NCT01766713.

Portable lactate analyzer for measuring lactate in cerebrospinal fluid (CSF) and plasma - method-comparison evaluations.

UNLABELLED: Increased plasma lactate levels can indicate the presence of metabolic disorders in HIV infected individuals. OBJECTIVE: To determine whether a portable analyzer is valid for measuring cerebrospinal fluid (CSF) and plasma lactate levels in HIV infected individuals. METHOD: CSF and plasma were collected from 178 subjects. Samples tested by the Accutrend portable analyzer were compared to those tested by a reference device (SYNCHRON LX 20). RESULTS: The portable analyzer had in plasma sensitivity of 0.95 and specificity 0.87. For CSF the specificity was 0.95; the sensitivity 0.33; the negative predictive value was 95% and the positive predictive value 33%. CONCLUSIONS: These findings support the validity of the portable analyzer in measuring lactate concentrations in CSF that fall within the normal range. The relatively poor positive predictive value indicates that a result above the reference range may represent a "false positive test", and should be confirmed by the reference device before concluding abnormality.

Portable lactate analyzer for measuring lactate in cerebrospinal fluid (CSF) and plasma ? method-comparison evaluations / Analisador portátil para dosar lactato no líquido cefalorraquidiano e plasma ? comparação de método

Increased plasma lactate levels can indicate the presence of metabolic disorders in HIV infected individuals. Objective: To determine whether a portable analyzer is valid for measuring cerebrospinal fluid (CSF) and plasma lactate levels in HIV infected individuals. Method: CSF and plasma were collected from 178 subjects. Samples tested by the Accutrend® portable analyzer were compared to those tested by a reference device (SYNCHRON LX® 20). Results: The portable analyzer had in plasma sensitivity of 0.95 and specificity 0.87. For CSF the specificity was 0.95; the sensitivity 0.33; the negative predictive value was 95% and the positive predictive value 33%. Conclusions: These findings support the validity of the portable analyzer in measuring lactate concentrations in CSF that fall within the normal range. The relatively poor positive predictive value indicates that a result above the reference range may represent a “false positive test”, and should be confirmed by the reference device before concluding abnormality. .

O aumento da concentração plasmática dos níveis de lactato pode indicar a presença de distúrbios metabólicos em indivíduos infectados pelo HIV. Objetivo: Determinar a validade do analisador portátil para quantificar os níveis de lactato no líquido cefalorraquidiano (LCR) e plasma em indivíduos infectados. Método: LCR e plasma foram coletados de 178 participantes. As amostras testadas com o analisador portátil Accutrend® e os resultados comparados com aqueles obtidos com o equipamento de referência (SYNCHRON LX® 20). Resultados: O analisador portátil teve, no plasma, sensibilidade de 0,95 e especificidade 0,87. No LCR a especificidade foi 0,95; a sensibilidade 0,33; o valor preditivo negativo foi de 95% e o valor preditivo positivo 33%. Conclusões: Estes dados suportam a validade dos resultados do analisador portátil em concentrações de lactato dentro da faixa normal. Os valores preditivos positivos relativamente baixos indicam que um resultado acima da faixa de referência pode representar um resultado “falso positivo”. .