The Association Between Non-Clinically Apparent Liver Fibrosis and Pulmonary Arterial Hypertension in Hispanic Patients

Background

Pulmonary arterial hypertension (PAH) is a deadly cardiopulmonary disease with multi-organ involvement including impaired liver function. Liver dysfunction in PAH is poorly understood but significantly associated with morbidity and mortality. Hispanics have a significantly higher prevalence of non-alcoholic fatty liver disease (NAFLD) and evidence of more advanced disease in comparison to other ethnic groups. The clinical impact of NAFLD in Hispanic PAH patients is unknown. We aimed to investigate the impact of a validated scoring system, non-alcoholic fatty liver disease fibrosis score (NFS), to predict the degree of liver fibrosis in a Hispanic PAH population and its relationship to hemodynamics, functional class, and outcomes.

Methods

A retrospective review of all treatment-naive Hispanic patients with group I World Health Organization (WHO) pulmonary hypertension (PH) at a single academic center between February 2016 and March 2021 was performed. Patients with history of substance or alcohol abuse, non-group I WHO PH, pre-existent liver disease, chronic kidney disease, atrial fibrillation, thyroid disease, and warfarin use were excluded from the study. The diagnosis of group I WHO PH was determined by cardiac catheterization after the exclusion of other etiologies. NFS was calculated for each patient and correlated with functional capacity, hemodynamics, N-terminal-pro-B-type natriuretic peptide (NT-proBNP), and survival.

Results

A total of 96 Hispanic patients were included in our study. The median age of patients in our cohort was 49 years (interquartile range: 15) and 69% of our cohort were females. Higher NFSs indicating advanced hepatic fibrosis (F3-F4) were found to correlate with elevated right-sided cardiac filling pressures (r = 0.27, P = 0.03), elevated levels of NT-proBNP (r = 0.32, P = 0.01), lower 6-minute walk distance (6MWD) (r = -0.49, P = 0.001), lower functional capacity (World Health Organization functional class, WHO-FC, r = -0.35, P = 0.051), a higher prevalence of diabetes (21.1% versus 51.9%, P = 0.001), a higher prevalence of risk factors for metabolic syndrome (81.5% versus 65.0%, P = 0.035), and worse 5-year survival rates.

Conclusion

In Hispanic patients with PAH, NFSs correlate with the degree of right-sided pressure overload. In addition, advanced NFSs were independently associated with lower 5-year survival rates and added prognostic information to other established risk parameters in PAH. This study suggests that screening for liver disease in this vulnerable patient population can aid in earlier detection leading to discussion of lifestyle modifications and possible escalation of PAH-targeted therapies, thus leading to potential improvement in survival rates.

Ultra-High-Resolution Time-of-Flight MR-Angiography for the Noninvasive Assessment of Intracranial Aneurysms, Alternative to Preinterventional DSA?

PURPOSE

The 3D time-of-flight (TOF) magnetic resonance angiography (MRA) at 3T shows high sensitivity for intracranial aneurysms but is inferior to three-dimensional digital subtraction angiography (3D-DSA) regarding aneurysm characteristics. We applied an ultra-high-resolution (UHR) TOF-MRA using compressed sensing reconstruction to investigate the diagnostic performance in preinterventional evaluation of intracranial aneurysms compared to conventional TOF-MRA and 3D-DSA.

METHODS

In this study 17 patients with unruptured intracranial aneurysms were included. Aneurysm dimensions, configuration, image quality and sizing of endovascular devices were compared between conventional TOF-MRA at 3T and UHR-TOF with 3D-DSA as gold standard. Quantitatively, contrast-to-noise ratios (CNR) were compared between TOF-MRAs.

RESULTS

On 3D-DSA, 25 aneurysms in 17 patients were detected. On conventional TOF, 23 aneurysms were detected (sensitivity: 92.6%). On UHR-TOF, 25 aneurysms were detected (sensitivity: 100%). Image quality was not significantly different between TOF and UHR-TOF (p = 0.17). Aneurysm dimension measurements were significantly different between conventional TOF (3.89 mm) and 3D-DSA (4.2 mm, p = 0.08) but not between UHR-TOF (4.12 mm) and 3D-DSA (p = 0.19). Irregularities and small vessels at the aneurysm neck were more frequently correctly depicted on UHR-TOF compared to conventional TOF. Comparison of the planned framing coil diameter and flow-diverter (FD) diameter revealed neither a statistically significant difference between TOF and 3D-DSA (coil p = 0.19, FD p = 0.45) nor between UHR-TOF and 3D-DSA (coil: p = 0.53, FD 0.33). The CNR was significantly higher in conventional TOF (p = 0.009).

CONCLUSION

In this pilot study, ultra-high-resolution TOF-MRA visualized all aneurysms and accurately depicted aneurysm irregularities and vessels at the base of the aneurysm comparably to DSA, outperforming conventional TOF. UHR-TOF with compressed sensing reconstruction seems to represent a non-invasive alternative to pre-interventional DSA for intracranial aneurysms.

Quantitative T2 mapping monitoring the maturation of engineered elastic cartilage in a rabbit model

BACKGROUND

Cartilage tissue engineering provides a promising approach to reconstruct craniofacial defects, and a noninvasive method is needed to assess its effectiveness. Although magnetic resonance imaging (MRI) has been used to evaluate articular cartilage in vivo, few studies focused on its feasibility in monitoring engineered elastic cartilage (EC).

METHODS

Auricular cartilage, silk fibroin (SF) scaffold, and EC consisting of rabbit auricular chondrocytes and SF scaffold were transplanted subcutaneously into the rabbit back. In eight weeks after transplantation, grafts were imaged by MRI using PROSET, PDW VISTA SPAIR, 3D T2 VISTA, 2D MIXED T2 Multislice, and SAG TE multiecho sequences, followed by histological examination and biochemical analysis. Statistical analyses were performed to identify the association between T2 values and biochemical indicator values of EC.

RESULTS

In vivo imaging shows that 2D MIXED T2 Multislice sequence (T2 mapping) clearly distinguished the native cartilage, engineered cartilage and fibrous tissue. T2 values showed high correlations with cartilage-specific biochemical parameters at different time points, especially the elastic cartilage specific protein elastin (ELN, r= -0.939, P < 0.001).

CONCLUSION

Quantitative T2 mapping can effectively detect the in vivo maturity of engineered elastic cartilage after subcutaneously transplantation. This study would promote the clinical application of MRI T2 mapping in monitoring engineered elastic cartilage in the repair of craniofacial defects.

Non-invasive assessment of liver abnormalities in pediatric Fontan patients

Liver abnormalities are well known among long-term survivors of Fontan palliation, which remains the definite surgery for complex congenital heart disease and single ventricle physiology. Pediatric data however are scarce. We assessed the prevalence and degree of liver abnormalities in pediatric Fontan patients through non-invasive investigations suitable for longitudinal follow-up. Thirty-five patients with a median age of 11.8 years (5.2-16.6) and median time since Fontan of 6 years (1.17-13.83) were studied. Each child underwent a blood test, liver Doppler ultrasound (US), and transient elastography (TE). Healthy children were used as controls for TE measurement. AST, ALT, γGT, and direct bilirubin were abnormal in respectively 12 (34%), 5 (14%), 24 (69%), and 7 (20%) patients, while platelet count was decreased in 7 (20%). Splenomegaly was present in 7 (20%) patients. Portal vein mean flow velocity was < 15 cm/s in 19 (54%) patients indicative of portal hypertension. Twenty-two patients (63%) showed inferior vena cava collapsibility index values below 17%, indicating venous congestion. Hepatic artery and superior mesenteric artery resistance index were inversely correlated with time post Fontan (p < 0.05). TE values in Fontan patients were significantly higher than controls, with a median of 12.6 versus 4.6 kPa (p < 0.001) and were already increased shortly after Fontan completion. Conclusion: Liver abnormalities are frequently observed in pediatric Fontan patients. The non-invasive investigations used were not able to confirm liver fibrosis or differentiate hepatic congestion from fibrosis. Based on our findings, we propose a prospective screening protocol with serial measurements of laboratory, (Doppler) US, and TE parameters. What is Known: • Hepatic dysfunction is a well-known consequence of the Fontan circulation. • The natural history of Fontan-associated liver disease in the pediatric age group remains unclear. What is New: • Liver abnormalities are frequently observed in pediatric Fontan patients; however, differentiating liver fibrosis and hepatic congestion with non-invasive investigations remains challenging. Sonographic Doppler measurements may improve our insight in both Fontan-associated liver disease development and the functioning of the Fontan circulation. • A prospective screening protocol is proposed to improve our ability to detect Fontan-associated liver disease early on and understand its natural history.

Combination antiretroviral therapy is associated with reduction in liver fibrosis scores in patients with HIV and HBV co-infection

Background

Liver fibrosis is common in individuals with HIV/HBV co-infection, but whether cART could reverses liver fibrosis is unclear.

Methods

This was a retrospective observational study. Binary logistic regression was used to assess predictors of liver fibrosis in individuals with HIV/HBV co-infection. Comparison of FIB-4 scores before and after cART were compared using X² test and t test.

Results

Four hundred and fifty-eight individuals with HIV/HBV co-infection were included in this study. It was found that cART (HR 0.016, 95% CI: 0.009–0.136; P < 0.001) was one of protection factors to against liver fibrosis. Forty individuals who had normal levels of ALT, AST and PLT during the whole course of diseases were stratified into FIB-4 < 1.45 (n = 14), 1.45 ≤ FIB-4 ≤ 3.25 (n = 19) and FIB-4 > 3.25 (n = 7) groups by their FIB-4 scores before cART. In 1.45 ≤ FIB-4 ≤ 3.25 group, 57.9%(11/19) of the individuals dropped to FIB-4 < 1.45 group by cART; in FIB-4 > 3.25 group, 85.7%(6/79) dropped to 1.45 ≤ FIB-4 ≤ 3.25 group, while 14.3%(1/7) dropped to FIB-4 < 1.45 group. In cART-naive group, 1 year, 2–5 years and 5–10 years post-cART groups, FIB-4 scores were 4.29 ± 0.43, 3.63 ± 0.38, 2.90 ± 0.36 and 2.52 ± 0.38, respectively (P = 0.034); and the incidence of liver fibrosis were 7.38%(104/141), 63.6%(98/154), 60.8%(62/102) and 47.5%(29/61), respectively (P = 0.004).

Conclusion

cART was associated with decreased FIB-4 scores and the benefit of cART in reversing liver fibrosis can sustain for a decade in patients with HIV/HBV co-infection.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12981-021-00419-y.

Platelet count as a screening tool for compensated cirrhosis in chronic viral hepatitis

BACKGROUND

Simple tools for clinicians to identify cirrhosis in patients with chronic viral hepatitis are medically necessary for treatment initiation, hepatocellular cancer screening and additional medical management.

AIM

To determine whether platelets or other laboratory markers can be used as a simple method to identify the development of cirrhosis.

METHODS

Clinical, biochemical and histologic laboratory data from treatment naive chronic viral hepatitis B (HBV), C (HCV), and D (HDV) patients at the NIH Clinical Center from 1985-2019 were collected and subjects were randomly divided into training and validation cohorts. Laboratory markers were tested for their ability to identify cirrhosis (Ishak ≥ 5) using receiver operating characteristic curves and an optimal cut-off was calculated within the training cohort. The final cut-off was tested within the validation cohort.

RESULTS

Overall, 1027 subjects (HCV = 701, HBV = 240 and HDV = 86), 66% male, with mean (standard deviation) age of 45 (11) years were evaluated. Within the training cohort (n = 715), platelets performed the best at identifying cirrhosis compared to other laboratory markers [Area Under the Receiver Operating Characteristics curve (AUROC) = 0.86 (0.82-0.90)] and sensitivity 77%, specificity 83%, positive predictive value 44%, and negative predictive value 95%. All other tested markers had AUROCs ≤ 0.77. The optimal platelet cut-off for detecting cirrhosis in the training cohort was 143 × 10⁹/L and it performed equally well in the validation cohort (n = 312) [AUROC = 0.85 (0.76-0.94)].

CONCLUSION

The use of platelet counts should be considered to identify cirrhosis and ensure optimal care and management of patients with chronic viral hepatitis.

Saturation oxygenation pressure index: a non-invasive bedside measure for severity of respiratory disease in neonates on CPAP

The treatment of respiratory distress in neonates ranges from non-invasive continuous positive airway pressure (CPAP) to advanced invasive mechanical ventilation. Monitoring on CPAP is often done by calculating oxygenation after blood gas analysis which is an invasive procedure. Saturation oxygen pressure index (SOPI) is a simple, non-invasive, bedside tool to monitor the severity of respiratory illness in neonates on CPAP. This study was aimed at validation of SOP index against AaDO2 and determine the cut-off values of SOPI for A-aDO2 of 70, 85 and100. This was a prospective observational study on 126 neonates with respiratory distress and treated with CPAP. The correlation between SOPI and A-aDO2 was validated using Bootstrap method. There was a significant positive correlation between SOPI and A-aDO2 with the Spearman correlation coefficient (rho) being 0.815 (p = 0). The mean coefficient of correlation after Bootstrap was 0.827 (p value < 0.0001). SOPI values of 1.52, 1.57 and 1.6 predicted A-aDO2 value of 70, 85 and 100 with a sensitivity of above 80% and specificity above 90%, respectively.Conclusion: SOPI has a significant positive correlation of 82.7% against A-aDO2 and can be a valuable tool to assess respiratory distress in neonates without arterial blood gas. What is Known: • Saturation oxygen pressure index (SOPI) is a non-invasive monitoring tool for neonates on N-CPAP. • SOPI has a good correlation with AaDO2. What is New: • Correlation of SOPI with AaDO2 is now validated. • Values between 1.52 and 1.88 indicate clinically useful range of AaDO2 for escalation of respiratory support from CPAP.

Non-invasive assessment of ICP in children: advances in ultrasound-based techniques

The assessment of intracranial pressure (ICP) in children with neurological disease remains a cornerstone in their routine management. The quest for a reliable, reproducible and radiation-free non-invasive technique for assessing ICP in children remains somewhat of a holy grail for neurosurgery. This work assesses some of the recent advances in ultrasound-based techniques, addressing both novel processes and modifications aimed at improving the accuracy of existing techniques.

[Hyperspectral imaging of gastrointestinal anastomoses]

INTRODUCTION

Anastomotic insufficiency (AI) remains the most feared surgical complication in gastrointestinal surgery, which is closely associated with a prolonged inpatient hospital stay and significant postoperative mortality. Hyperspectral imaging (HSI) is a relatively new medical imaging procedure which has proven to be promising in tissue identification as well as in the analysis of tissue oxygenation and water content. Until now, no data exist on the in vivo HSI analysis of gastrointestinal anastomoses.

METHODS

Intraoperative images were obtained using the TIVITA™ tissue system HSI camera from Diaspective Vision GmbH (Pepelow, Germany). In 47 patients who underwent gastrointestinal surgery with esophageal, gastric, pancreatic, small bowel or colorectal anastomoses, 97 assessable recordings were generated. Parameters obtained at the sites of the anastomoses included tissue oxygenation (StO₂), the tissue hemoglobin index (THI), near-infrared (NIR) perfusion index, and tissue water index (TWI).

RESULTS

Obtaining and analyzing the intraoperative images with this non-invasive imaging system proved practicable and delivered good results on a consistent basis. A NIR gradient along and across the anastomosis was observed and, furthermore, analysis of the tissue water and oxygenation content showed specific changes at the site of anastomosis.

CONCLUSION

The HSI method provides a non-contact, non-invasive, intraoperative imaging procedure without the use of a contrast medium, which enables a real-time analysis of physiological anastomotic parameters, which may contribute to determine the "ideal" anastomotic region. In light of this, the establishment of this methodology in the field of visceral surgery, enabling the generation of normal or cut off values for different gastrointestinal anastomotic types, is an obvious necessity.

Chronic Granulomatous Disorder-Associated Colitis Can Be Accurately Evaluated with MRI Scans and Fecal Calprotectin Level

Purpose

Colitis is a common and serious complication of chronic granulomatous disorder (CGD) and requires assessment. Colonoscopy is invasive and carries risks of serious complication. We therefore assessed non-invasive monitoring via magnetic resonance imaging (MRI). We also evaluated fecal calprotectin (FCP), the Harvey-Bradshaw index (HBI) clinical score, and serum cytokines.

Methods

We recruited 10 patients with CGD (8 males, mean age 29.6 years), scored a modified HBI, and obtained stool for FCP. The following day we took blood for cytokine measurement via Luminex, performed MR enterography (scored by two independent radiologists using three systems: London score, CDMI, and MaRIA) followed by colonoscopy with disease activity measurement via ulcerative colitis endoscopic index of severity (UCEIS). We assessed patient experience after each investigation and overall preference with follow-up questionnaires.

Results

MRI scores correlated well with colonoscopic gold standard (for London score R² 0.91, p < 0.0001; for CDMI R² 0.83, p = 0.0006; for MaRIA R² 0.89, p = 0.0002). MRI was better tolerated and generally preferred, quicker, and visualized the entire large bowel whereas colonoscopy did not reach the terminal ileum in 3 participants. Elevated FCP accurately differentiated patients with colitis from those without, and log(calprotectin) correlated well with disease activity (R² 0.71, p = 0.009). Serum interleukin (IL)-12 concentration correlated with colitis activity but IL-1β and TNF did not. Harvey-Bradshaw index did not correlate with colitis activity.

Conclusions

MRI and fecal calprotectin are useful methods for monitoring CGD colitis and should reduce the need for colonoscopy in these patients. IL-12 may represent an appropriate target for treatment.

Electronic supplementary material

The online version of this article (10.1007/s10875-019-00651-2) contains supplementary material, which is available to authorized users.

[Present situation on non-invasive assessment of liver fibrosis/cirrhosis]

Patients with chronic liver disease often have varying degrees of hepatic fibrosis, and further exacerbations can lead to cirrhosis and even hepatocellular carcinoma. Liver biopsy is the gold standard for the diagnosis of liver fibrosis/cirrhosis, but there are still many limitations. In recent years, non-invasive assessments for liver fibrosis/cirrhosis have gained rapid development. Of these techniques, two different approaches have been validated in clinical practice: imaging methods based on the measurement of liver stiffness, and biological methods based on the serum biomarkers. The two different approaches can complement each other. Current non-invasive assessments for liver fibrosis/cirrhosis tend to be reliable for the detection of advanced fibrosis and cirrhosis, but often lack to distinguish the different early stage of liver fibrosis. Further improving the accuracy of non-invasive assessments might play an important role for clinical management of liver diseases.

A new CFD based non-invasive method for functional diagnosis of coronary stenosis

Background

Accurate functional diagnosis of coronary stenosis is vital for decision making in coronary revascularization. With recent advances in computational fluid dynamics (CFD), fractional flow reserve (FFR) can be derived non-invasively from coronary computed tomography angiography images (FFR_CT) for functional measurement of stenosis. However, the accuracy of FFR_CT is limited due to the approximate modeling approach of maximal hyperemia conditions. To overcome this problem, a new CFD based non-invasive method is proposed.

Methods

Instead of modeling maximal hyperemia condition, a series of boundary conditions are specified and those simulated results are combined to provide a pressure-flow curve for a stenosis. Then, functional diagnosis of stenosis is assessed based on parameters derived from the obtained pressure-flow curve.

Results

The proposed method is applied to both idealized and patient-specific models, and validated with invasive FFR in six patients. Results show that additional hemodynamic information about the flow resistances of a stenosis is provided, which cannot be directly obtained from anatomy information. Parameters derived from the simulated pressure-flow curve show a linear and significant correlations with invasive FFR (r > 0.95, P < 0.05).

Conclusion

The proposed method can assess flow resistances by the pressure-flow curve derived parameters without modeling of maximal hyperemia condition, which is a new promising approach for non-invasive functional assessment of coronary stenosis.

Non-radiographic methods of measuring global sagittal balance: a systematic review

Background

Global sagittal balance, describing the vertical alignment of the spine, is an important factor in the non-operative and operative management of back pain. However, the typical gold standard method of assessment, radiography, requires exposure to radiation and increased cost, making it unsuitable for repeated use. Non-radiologic methods of assessment are available, but their reliability and validity in the current literature have not been systematically assessed. Therefore, the aim of this systematic review was to synthesise and evaluate the reliability and validity of non-radiographic methods of assessing global sagittal balance.

Methods

Five electronic databases were searched and methodology evaluated by two independent reviewers using the13-item, reliability and validity, Brink and Louw critical appraisal tool.

Results

Fourteen articles describing six methodologies were identified from 3940 records. The six non-radiographic methodologies were biophotogrammetry, plumbline, surface topography, infra-red motion analysis, spinal mouse and ultrasound. Construct validity was evaluated for surface topography (R = 0.49 and R = 0.68, p < 0.001), infra-red motion-analysis (ICC = 0.81) and plumbline testing (ICC = 0.83). Reliability ranged from moderate (ICC = 0.67) for spinal mouse to very high for surface topography (Cronbach α = 0.985). Measures of agreement ranged from 0.9 mm (plumbline) to 22.94 mm (infra-red motion-analysis). Variability in study populations, reporting parameters and statistics prevented a meta-analysis.

Conclusions

The reliability and validity of the non-radiographic methods of measuring global sagittal balance was reported within 14 identified articles. Based on this limited evidence, non-radiographic methods appear to have moderate to very high reliability and limited to three methodologies, moderate to high validity. The overall quality and methodological approaches of the included articles were highly variable. Further research should focus on the validity of non-radiographic methods with a greater adherence to reporting actual and clinically relevant measures of agreement.

Tegafur-uracil-induced rapid development of advanced hepatic fibrosis

Tegafur-uracil has been reported to have only minor adverse effects and is associated with liver injury in 1.79% of Japanese patients. The development of tegafur-uracil-induced hepatic fibrosis with portal hypertension is rare. Here, we report a case of a 74-year-old woman with rapidly developing tegafur-uracil-induced hepatic fibrosis. The patient had no history of liver disease and had been treated with tegafur-uracil for 8 mo after breast cancer surgery. The patient was admitted to our hospital for abdominal distension and leg edema associated with liver dysfunction. Computed tomography imaging revealed massive ascites and splenomegaly, and a non-invasive assessment of liver fibrosis indicated advanced fibrosis. The histopathological findings revealed periportal fibrosis and bridging fibrosis with septation. The massive ascites resolved after discontinuing tegafur-uracil. These findings suggest that advanced hepatic fibrosis can develop from a relatively short-term administration of tegafur-uracil and that non-invasive assessment is useful for predicting hepatic fibrosis.

Hepatic steatosis and fibrosis: Non-invasive assessment

Chronic liver disease is a major cause of morbidity and mortality worldwide and usually develops over many years, as a result of chronic inflammation and scarring, resulting in end-stage liver disease and its complications. The progression of disease is characterised by ongoing inflammation and consequent fibrosis, although hepatic steatosis is increasingly being recognised as an important pathological feature of disease, rather than being simply an innocent bystander. However, the current gold standard method of quantifying and staging liver disease, histological analysis by liver biopsy, has several limitations and can have associated morbidity and even mortality. Therefore, there is a clear need for safe and non-invasive assessment modalities to determine hepatic steatosis, inflammation and fibrosis. This review covers key mechanisms and the importance of fibrosis and steatosis in the progression of liver disease. We address non-invasive imaging and blood biomarker assessments that can be used as an alternative to information gained on liver biopsy.

Prevalence and predictors of liver steatosis and fibrosis in unselected patients with HIV mono-infection

OBJECTIVES

Significant liver disease may develop in HIV mono-infected patients, usually associated with fatty liver and/or cART exposure. We estimated the prevalence and predictors of hepatic steatosis and fibrosis as assessed by ultrasound and transient elastography (TE).

METHODS

We enrolled 125 consecutive HIV mono-infected patients who underwent ultrasound and TE. Clinical, biochemical, immunological, virological features and medication history were analysed.

RESULTS

Mean age was 39.5±10.3years and 91% were male. Metabolic syndrome (MS) was present in 9.8%, diabetes in 5.6%, hypertension in 9.7%, dyslipidemia in 32.8%. Increased AST and ALT were found in 5.6% and 16.8% respectively. Eighty-five (68%) patients were on cART (median length of treatment of 3 years, IQR 0-17). Hepatic steatosis was detected in 61 (55%) patients and was independently associated with male sex (OR 14.6, 95% CI 1.44-148.17), age (OR 1.082, 95% CI 1.01-1.16), HOMA (OR 2.56, 95% CI 1.101-5.96) and GGT (OR 1.037, 95% CI 1.007-1.075). Significant fibrosis (stiffness>7.4kPa) was present in 22 patients (17.6%) and was significantly associated with MS (OR 3.99, 95% CI 1.001-16.09).

CONCLUSIONS

Liver fibrosis can develop in asymptomatic HIV mono-infected patients. This is likely associated with NAFLD and usually manifests with normal transaminases. Non-invasive screening for the presence of NAFLD and fibrosis should be considered in the routine care of such patients.

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.

Abnormally cleaving embryos are able to produce live births: a time-lapse study

PURPOSE

This study investigated the prevalence of abnormally cleaved embryos and determined which types of abnormally cleaved embryos (1-3c, 2-4c, 3-5c, 4-6c), might be suitable for transfer based on live birth data.

METHODS

One hundred seventy-one women (whose transferred embryos were confirmed to be either fully implanted or fully unimplanted) provided 1256 embryos, which were analyzed.

RESULTS

Of these embryos, 320 embryos were transferred, of these transferred embryos, 291 embryos were normal and 29 embryos were abnormal, which five embryos were not analyzed because each one was presented one abnormal cleavage type. These 24 embryos were divided into four groups. Inclusion criteria were as follows: women under 37 years of age undergoing first fresh in vitro fertilization (IVF) treatment with a basal antral follicle count of 5-15, body mass index (BMI) of 18-25 kg/m(2), number of retrieved oocytes between 5 and 20, and tubal factors as the cause of infertility. Time-lapse imaging analysis software was used to compare temporal parameters of normal cleavage and abnormal cleavage groups (there were four abnormal groups, based on the prevalence of abnormal cleavage embryos). Cleavage times were analyzed before the abnormal cleavage occurred, and time intervals were analyzed after the abnormal cleavage based upon the types of abnormal cleavage. In addition, the time intervals of t4-t3 and t8-t5 were also analyzed; corresponding time parameters were measured in the normal group as well. Implantation rate, clinical pregnancy rate, ongoing pregnancy rate, and live birth rate were also measured in the normally cleaved and abnormally cleaved embryos. The prevalence of abnormal cleavage was 15.92% (200/1256). T8-t5 was the most important parameter in the prediction of potential development (production of a live-born baby) of abnormally cleaving embryos.

CONCLUSIONS

Abnormally cleaving embryos were able to produced live births with T8-t5 the best parameter to predict the developmental potential of abnormally cleaving embryos.

Liver Steatosis and Fibrosis in OSA patients After Long-term CPAP Treatment: A Preliminary Ultrasound Study

In cases of morbid obesity, obstructive sleep apnea (OSA) was associated with biopsy-proven liver damage. The role of non-invasive techniques to monitor liver changes during OSA treatment with continuous positive airway pressure (CPAP) is unknown. We used non-invasive ultrasound techniques to assess liver steatosis and fibrosis in severe OSA patients at diagnosis and during long-term CPAP treatment. Fifteen consecutive patients with severe OSA (apnea hypopnea index 52.5 ± 19.1/h) were studied by liver ultrasound and elastography (Fibroscan) at 6-mo (n = 3) or 1-y (n = 12) follow-up. Mean age was 49.3 ± 11.9 y, body mass index (BMI) was 35.4 ± 6.4 kg/m(2). Adherence to CPAP was ≥5 h/night. At baseline, most patients had severe liver steatosis independent of BMI; at follow-up, liver steatosis was not statistically different, but a relationship between severity of steatosis and BMI became apparent (Spearman's rho: 0.53, p = 0.03). Significant fibrosis as assessed by Fibroscan was absent at diagnosis or follow-up (failure or unreliable measurements in four markedly obese patients). Therefore, ultrasound liver assessment is feasible in most OSA patients, and CPAP treatment may positively affect liver steatosis.

High-frequency ultrasonic imaging of growth and development in manufactured engineered oral mucosal tissue surfaces

This study uses high-resolution ultrasound to examine the growth and development of engineered oral mucosal tissues manufactured under aseptic conditions. The specimens are a commercially available natural tissue scaffold, AlloDerm, and oral keratinocytes seeded onto AlloDerm to form an ex vivo-produced oral mucosal equivalent (EVPOME) suitable for intra-oral grafting. The seeded cells produce a keratinized protective upper layer that smooths out any remaining surface irregularities on the underlying AlloDerm. Two-dimensional acoustic imaging of unseeded AlloDerm and developing EVPOMEs was performed on each day of their growth and development, each tissue specimen being imaged under aseptic conditions (total time from seeding to maturation: 11 d). Ultrasonic monitoring offers us the ability to determine the constituents of the EVPOME that are responsible for changes in its mechanical behavior during the manufacturing process. Ultrasonic monitoring affords us an opportunity to non-invasively assess, in real time, tissue-engineered constructs before release for use in patient care.

Non-invasive assessment of elastic modulus of arterial constructs during cell culture using ultrasound elasticity imaging

Mechanical strength is a key design factor in tissue engineering of arteries. Most existing techniques assess the mechanical property of arterial constructs destructively, leading to sacrifice of a large number of animals. We propose an ultrasound-based non-invasive technique for the assessment of the mechanical strength of engineered arterial constructs. Tubular scaffolds made from a biodegradable elastomer and seeded with vascular fibroblasts and smooth muscle cells were cultured in a pulsatile-flow bioreactor. Scaffold distension was computed from ultrasound radiofrequency signals of the pulsating scaffold via 2-D phase-sensitive speckle tracking. Young's modulus was then calculated by solving the inverse problem from the distension and the recorded pulse pressure. The stiffness thus computed from ultrasound correlated well with direct mechanical testing results. As the scaffolds matured in culture, ultrasound measurements indicated an increase in Young's modulus, and histology confirmed the growth of cells and collagen fibrils in the constructs. The results indicate that ultrasound elastography can be used to assess and monitor non-invasively the mechanical properties of arterial constructs.