Significant positive association of endotoxemia with histological severity in 237 patients with non-alcoholic fatty liver disease.

BACKGROUND: Patients with nonalcoholic steatohepatitis (NASH) have gut dysbiosis and intestinal bacterial overgrowth. AIM: To test the hypothesis that endotoxemia is associated with the histological severity of nonalcoholic fatty liver disease (NAFLD) and determine factors associated with endotoxemia. METHODS: The endotoxemia markers lipopolysaccharide-binding protein (LBP) and endotoxin levels were measured in 237 NAFLD patients 1 day before liver biopsy. Biomarkers of liver injury and transient elastography were performed as additional markers of disease severity. RESULTS: A total of 114/237 (48%) patients had NASH and 80/237 (34%) had F2-4 fibrosis. LBP was correlated with lobular inflammation (P=.001), while both LBP (P=.0004) and endotoxin levels (P=0.008) were correlated with fibrosis. LBP was also correlated with cytokeratin-18 fragments (P=.002) and aspartate aminotransferase-to-alanine aminotransferase ratio (P=.006), and both LBP (P=.019) and endotoxin (P=.006) were correlated with liver stiffness measurement by transient elastography. LBP was increased in patients with NASH (15.3±4.6 vs 13.8±3.3 µg/mL; P=.005) and F2-4 fibrosis (15.4±4.4 vs 14.0±3.7 µg/mL; P=.008). Interestingly, patients harbouring the TM6SF2 rs58542926 T allele that predispose to NAFLD/NASH had higher LBP level. By multivariate analysis, gender, higher body mass index and glycated haemoglobin, and TM6SF2 variants were independent factors associated with increased LBP level. CONCLUSIONS: Endotoxemia is positively associated with NASH and significant fibrosis. The association between TM6SF2 and endotoxemia warrants further investigations. The findings may shed light on the pathogenesis of NASH and inform a novel treatment target.

Carotid Webs and Recurrent Ischemic Strokes in the Era of CT Angiography.

BACKGROUND AND PURPOSE: Carotid webs may cause recurrent ischemic stroke. We describe the prevalence, demographics, clinical presentation, imaging features, histopathology, and stroke risk associated with this under-recognized lesion. MATERIALS AND METHODS: A carotid web was defined on CTA as a thin intraluminal filling defect along the posterior wall of the carotid bulb just beyond the carotid bifurcation on oblique sagittal section CTA that was seen as a septum on axial CTA. Using a prospective case series from April 2013 to April 2014, we describe the demographics, spectrum of imaging features on CTA, and histopathology of these carotid webs. From a retrospective analysis of patients at our center from May 2012 to April 2013 who had a baseline head and neck CTA followed by a brain MR imaging within 1-2 days of the CTA, we determine the period prevalence of carotid webs and the prevalence of ipsilateral stroke on imaging. RESULTS: In the prospective series, the mean age was 50 years (range, 41-55 years); 5/7 patients were women. Recurrent stroke was seen in 5/7 (71.4%) patients with the carotid web; time to recurrence ranged from 1 to 97 months. Histopathology suggested a high probability of fibromuscular dysplasia. In the retrospective series, carotid webs were seen in 7/576 patients for a hospital-based-period prevalence of 1.2% (95% CI, 0.4%-2.5%). Two of these 7 patients had acute stroke in the vascular territory of the carotid web. CONCLUSIONS: A carotid web may contribute to recurrent ischemic stroke in patients with no other determined stroke mechanism. Intimal variant fibromuscular dysplasia is the pathologic diagnosis in most cases. The prevalence of carotid web is low, while the optimal management strategy remains unknown.

Atomic scale investigation of non-equilibrium segregation of boron in a quenched Mo-free martensitic steel.

B-added low carbon steels exhibit excellent hardenability. The reason has been frequently attributed to B segregation at prior austenite grain boundaries, which prevents the austenite to ferrite transformation and favors the formation of martensite. The segregation behavior of B at prior austenite grain boundaries is strongly influenced by processing conditions such as austenitization temperatures and cooling rates and by alloying elements such as Mo, Cr, and Nb. Here an local electrode atom probe was employed to investigate the segregation behavior of B and other alloying elements (C, Mn, Si, and Cr) in a Cr-added Mo-free martensitic steel. Similar to our previous results on a Mo-added steel, we found that in both steels B is segregated at prior austenite grain boundaries with similar excess values, whereas B is neither detected in the martensitic matrix nor at martensite-martensite boundaries at the given cooling rate of 30K/s. These results are in agreement with the literature reporting that Cr has the same effect on hardenability of steels as Mo in the case of high cooling rates. The absence of B at martensite-martensite boundaries suggests that B segregates to prior austenite grain boundaries via a non-equilibrium mechanism. Segregation of C at all boundaries such as prior austenite grain boundaries and martensite-martensite boundaries may occur by an equilibrium mechanism.

Effects of meal composition on postprandial incretin, glucose and insulin responses after surgical and medical weight loss.

BACKGROUND: Meal tolerance tests are frequently used to study dynamic incretin and insulin responses in the postprandial state; however, the optimal meal that is best tolerated and suited for hormonal response following surgical and medical weight loss has yet to be determined. OBJECTIVE: To evaluate the tolerability and effectiveness of different test meals in inducing detectable changes in markers of glucose metabolism in individuals who have undergone a weight loss intervention. METHODS: Six individuals who underwent surgical or medical weight loss (two Roux-en-Y gastric bypass, two sleeve gastrectomy and two medical weight loss) each completed three meal tolerance tests using liquid-mixed, solid-mixed and high-fat test meals. The tolerability of each test meal, as determined by the total amount consumed and palatability, as well as fasting and meal-stimulated glucagon-like peptide, glucose-dependent insulinotropic polypeptide, insulin and glucose were measured. RESULTS: Among the six individuals, the liquid-mixed meal was better and more uniformly tolerated with a median meal completion rate of 99%. Among the four bariatric surgical patients, liquid-mixed meal stimulated on average a higher glucagon-like peptide (percent difference: 83.7, 89), insulin secretion (percent difference: 155.1, 158.7) and glucose-dependent insulinotropic polypeptide (percent difference: 113.5, 34.3) compared with solid-mixed and high-fat meals. CONCLUSIONS: The liquid-mixed meal was better tolerated with higher incretin and insulin response compared with the high-fat and solid-mixed meals and is best suited for the evaluation of stimulated glucose homeostasis.

Small bowel resection induces long-term changes in the enteric microbiota of mice.

PURPOSE: The enteric microbiome is known to play a major role in healthy gut homeostasis and several disease states. It may also contribute to both the intestinal recovery and complications that occur in patients with short bowel syndrome. The extent and nature of alterations to the gut microbiota following intestinal resection, however, are not well studied in a controlled setting. The purpose of this investigation is to characterize the effects of massive small bowel resection on the murine enteric microflora. METHODS: Wild-type C57BL6 mice, following a week of acclamation to a liquid rodent diet, underwent either 50% proximal small bowel resection (SBR) or a sham operation. Mice were sacrificed, and enteric contents from the small bowel, cecum, and stool were harvested at 7 and 90 days post-operatively. DNA was isolated, and the V3-V5 regions of the 16s rRNA gene amplified and pyrosequenced on a Roche 454 platform. Sequences were clustered into operation taxonomic units and classified. Communities were then analyzed for diversity and phylogenic composition. RESULTS: In the long-term group, the microbes inhabiting the ileum of mice undergoing SBR and sham operation differed significantly at the genus level (p < 0.001). Small bowel contents collected before and after SBR also differed significantly (p = 0.006). This was driven by an increase in Lactobacillus and decrease in Enterobacteriaceae species in mice undergoing SBR. No difference was seen in the long-term stool or in stool, cecal, or ileal contents in the short-term. No difference in microbial community diversity was found in any group. CONCLUSION: Bowel resection induces long-term changes in the microbial community of the murine ileum, but not at more distal sites of the gastrointestinal tract. The increase in Lactobacillus encountered small bowel of resected mice correlates with limited previous studies. These changes may reflect an adaptive response of the microbiota to maximize energy extraction, but further studies are needed to establish the role played by this altered community.

Non-invasive algorithm of enhanced liver fibrosis and liver stiffness measurement with transient elastography for advanced liver fibrosis in chronic hepatitis B.

BACKGROUND: The accuracy of Enhanced Liver Fibrosis (ELF; ADVIA Centaur, Siemens Healthcare Diagnostics, Tarrytown, NY, USA) in assessing liver fibrosis in chronic hepatitis B (CHB) is to be determined. AIM: To derive and validate a combined ELF-liver stiffness measurement (LSM) algorithm to predict advanced fibrosis in CHB patients. METHODS: Using the data of a previously reported cohort of 238 CHB patients, an ALT-based LSM algorithm for liver fibrosis was used as a training cohort to evaluate the performance of ELF against liver histology. The best combined ELF-LSM algorithm was then validated in new cohort of 85 CHB patients not previously reported. RESULTS: In the training cohort, LSM has better performance of diagnosing advanced (≥F3) fibrosis (area under the receiver operating characteristics curve [AUROC] 0.83, 95% confidence interval [CI 0.76-0.91] than ELF (AUROC 0.69, 95% CI 0.63-0.75). The optimal cut-off values of ELF were 8.4 to exclude advanced fibrosis, and 10.8 to confirm advanced fibrosis. In the training cohort, an ELF ≤ 8.4 had a sensitivity of 95% to exclude advanced fibrosis; an ELF > 10.8 had a specificity of 92% to confirm advanced fibrosis. In the combined algorithm, low ELF or low LSM could be used to exclude advanced fibrosis as both of them had high sensitivity (≥90%). To confirm advanced fibrosis, agreement between high ELF and high LSM could improve the negative predictive value specificity (from 65% and 74% to 80%). CONCLUSIONS: An Enhanced Liver Fibrosis - liver stiffness measurement algorithm could improve the accuracy of prediction of either ELF or LSM alone. Liver biopsy could be correctly avoided in approximately 60% of patients.

Understanding the detection of carbon in austenitic high-Mn steel using atom probe tomography.

A high-Mn TWIP steel having composition Fe-22Mn-0.6C (wt%) is considered in this study, where the need for accurate and quantitative analysis of clustering and short-range ordering by atom probe analysis requires a better understanding of the detection of carbon in this system. Experimental measurements reveal that a high percentage of carbon atoms are detected as molecular ion species and on multiple hit events, which is discussed with respect to issues such as optimal experimental parameters, correlated field evaporation and directional walk/migration of carbon atoms at the surface of the specimen tip during analysis. These phenomena impact the compositional and spatial accuracy of the atom probe measurement and thus require careful consideration for further cluster-finding analysis.

Atomic scale investigation of redistribution of alloying elements in pearlitic steel wires upon cold-drawing and annealing.

A local electrode atom probe has been employed to analyze the redistribution of alloying elements including Si, Mn, and Cr in pearlitic steel wires upon cold-drawing and subsequent annealing. It has been found that the three elements undergo mechanical mixing upon cold-drawing at large strains, where Mn and Cr exhibit a nearly homogeneous distribution throughout both ferrite and cementite, whereas Si only dissolves slightly in cementite. Annealing at elevated temperatures leads to a reversion of the mechanical alloying. Si atoms mainly segregate at well-defined ferrite (sub)grain boundaries formed during annealing. Cr and Mn are strongly concentrated in cementite adjacent to the ferrite/cementite interface due to their lower diffusivities in cementite than in ferrite.

Assessment of non-alcoholic fatty liver disease using serum total cell death and apoptosis markers.

BACKGROUND: The diagnosis of non-alcoholic fatty liver disease (NAFLD), non-alcoholic steatohepatitis (NASH) and fibrosis relies on liver biopsy. Non-invasive assessments are urgently needed. AIM: To evaluate cell apoptotic marker cytokeratin-18 M30 and total cell death markers cytokeratin-18 M65/M65ED for the assessment and monitoring of NAFLD. METHODS: A cohort of 147 patients with biopsy-proven NAFLD and 73 controls were enrolled, including 51 patients who received paired liver biopsies 36 months apart. Biomarkers were determined by enzyme-linked immunosorbent assay. RESULTS: M30, M65 and M65ED increased in a stepwise fashion in control subjects, patients with non-NASH, NAFLD and NASH (all P < 0.001). All biomarkers had similarly high accuracy over 0.9 in predicting NAFLD and moderate accuracy around 0.7 in predicting NASH. Among patients with paired liver biopsies, changes in M30, M65 and M65ED positively correlated with disease progression (rho = 0.42, 0.32 and 0.39; P = 0.002, 0.023 and 0.005 respectively), and only changes in M65 and M65ED correlated with fibrosis progression (rho = 0.29, 0.34; P = 0.038, 0.015 respectively). Both M30 and M65 had area under receiver-operating characteristics curve above 0.8 in predicting disease progression. At cut-off of 236 U/L, changes of M65ED had 88% NPV and 59% PPV to exclude and predict fibrosis progression. CONCLUSIONS: Cytokeratin-18 M30 and M65/M65ED have moderate accuracy in detecting non-alcoholic steatohepatitis. Changes in the biomarkers also correlate with histological progression. However, development of new biomarkers is still required to improve the diagnostic accuracy.

Intracranial electroencephalogram to evaluate refractory temporal and frontal lobe epilepsy.

OBJECTIVE: We undertook a collaborative study in a multidisciplinary team to channel refractory epilepsy patients to test a hypothesis about placement of intracranial electroencephalography arrays. DESIGN: This was a descriptive case series. Prospective non-invasive presurgical evaluations were based on clinical semiology, magnetic resonance imaging, video-electroencephalography findings and neuropsychological assessments. If the results were discordant, a hypothesis was generated using individualised combinations of positron emission tomography, single-photon emission computed tomography, functional magnetic resonance imaging and Wada tests. The indications for intracranial electroencephalography were: (a) focal magnetic resonance imaging, ictal/interictal scalp electroencephalography with variable results (group A); (b) multi-focal magnetic resonance imaging, focal/multi-focal ictal scalp electroencephalography (group B); (c) non-lesional magnetic resonance imaging, focal/multi-focal ictal scalp electroencephalography (group C). We evaluated whether the seizure-onset zones and eloquent areas were delineated, surgical outcomes (if operated on), and pathology results. SETTING: A tertiary referral centre for neurology in Hong Kong. PATIENTS: A total of 105 refractory epilepsy patients completed non-invasive presurgical evaluations over the period 2007 to 2009. Thirty-two patients were eligible for direct resective surgery, and another 25 patients had a testing hypothesis formulated. Of these 25 patients, 10 were eligible for intracranial electroencephalography based on technical/financial considerations. RESULTS: All 10 patients (group A=2, group B=4, group C=4) had their epileptogenic zones defined. Six patients underwent functional mapping, all of whom had their eloquent areas defined. Seven of the 10 patients underwent resective surgery; four of them achieved Engel class I/II outcomes. The dichotomised outcomes were 100% (group A), 50% (group B), and 33% (group C) achieving Engel class I/II. Two patients had asymptomatic subdural haematoma. There was no intracranial infection or operative mortality. In five (71%) of seven of the patients, a histological diagnosis was established. CONCLUSION: Proper deployment of intracranial electroencephalography is useful in the presurgical evaluation of patients with refractory epilepsy. This modality of management is potentially of benefit for patients with refractory epilepsy, but is underutilised locally.

Pulsed-laser atom probe studies of a precipitation hardened maraging TRIP steel.

A precipitation hardened maraging TRIP steel was analyzed using a pulsed laser atom probe. The laser pulse energy was varied from 0.3 to 1.9 nJ to study its effect on the measured chemical compositions and spatial resolution. Compositional analyses using proximity histograms did not show any significant variations in the average matrix and precipitate compositions. The only remarkable change in the atom probe data was a decrease in the ++/+ charge state ratios of the elements. The values of the evaporation field used for the reconstructions exhibit a linear dependence on the laser pulse energy. The adjustment of the evaporation fields used in the reconstructions for different laser pulse energies was based on the correlation of the obtained cluster shapes to the TEM observations. No influence of laser pulse energy on chemical composition of the precipitates and on the chemical sharpness of their interfaces was detected.

Atom probe tomography characterization of heavily cold drawn pearlitic steel wire.

Atom Probe Tomography (APT) was used to analyze the carbon distribution in a heavily cold drawn pearlitic steel wire with a true strain of 6.02. The carbon concentrations in cementite and ferrite were separately measured by a sub-volume method and compared with the literature data. It is found that the carbon concentration in ferrite saturates with strain. The carbon concentration in cementite decreases with the lamellar thickness, while the carbon atoms segregate at dislocations or cell/grain boundaries in ferrite. The mechanism of cementite decomposition is discussed in terms of the evolution of dislocation structure during severe plastic deformation.

Spontaneous regression of primary cutaneous Epstein-Barr virus-positive, CD30-positive anaplastic large T-cell lymphoma in a heart-transplant recipient.

We presented a rare case of primary cutaneous Epstein-Barr virus-positive, CD30-positive anasplastic large cell lymphoma in a 64-year-old man who had received a heart transplant 11 years previously. The first presenting symptom was the appearance of erythematous skin nodules on the right leg. The lesions subsided with dose reduction of immunosuppressant alone. There was no recurrence 9 months after the first diagnosis. We propose that dose reduction of immunosuppressant alone may be an effective treatment for localized, indolent, post-transplant-related primary cutaneous lymphoma. Our case shows the importance of regular surveillance of skin cancer in patients who have received organ transplant.

Alanine aminotransferase-based algorithms of liver stiffness measurement by transient elastography (Fibroscan) for liver fibrosis in chronic hepatitis B.

The aim of this study is to know the liver stiffness measurement (LSM) cutoffs for different stages of liver fibrosis in chronic hepatitis B (CHB) and to investigate the effect of alanine aminotransferase (ALT) on LSM. We prospectively studied consecutive CHB patients undergoing liver biopsy and transient elastography examinations. Diagnostic performance of LSM for different degrees of liver fibrosis was evaluated. One hundred and sixty-one CHB patients with adequate liver biopsy sample size were studied. Area under receiver operating characteristics curves of LSM for no fibrosis (F0 vs F1-4), bridging fibrosis (F0-2 vs F3-4) and liver cirrhosis (F0-3 vs F4) was 0.80 (95% CI: 0.68-0.92), 0.87 (95% CI: 0.82-0.93) and 0.93 (95% CI: 0.89-0.97) respectively. For liver cirrhosis, these optimal cutoff values were 8.4 kPa (98% sensitivity), 9.0 kPa (maximum sum of sensitivity and specificity), 13.4 kPa (94% specificity) and 13.4 kPa (maximum diagnostic accuracy, 85%) respectively. Patients with the same fibrosis staging but higher ALT levels tend to have higher LSM, and the diagnostic performance for low stage fibrosis was most seriously affected when ALT was elevated. Different LSM cutoff values and algorithms were derived for normal and elevated ALT levels. Based on these algorithms, liver biopsy can be avoided in 62% and 58% of patients with normal and elevated ALT respectively. In conclusion, transient elastography is a reasonable noninvasive tool to substitute liver biopsy among the lowest and highest risk patients for the assessment of liver fibrosis.

Metabolic syndrome increases the risk of liver cirrhosis in chronic hepatitis B.

BACKGROUND: Metabolic syndrome is associated with non-alcoholic steatohepatitis and cryptogenic cirrhosis. Whether metabolic syndrome affects the severity of chronic hepatitis B (CHB) is unclear. AIM: We aimed to study the relationship between metabolic syndrome and the risk of liver cirrhosis in patients with CHB. METHODS: We prospectively recruited patients with CHB from primary care and hospital clinics for liver stiffness measurement (LSM) with transient elastography to diagnose early cirrhosis. Probable cirrhosis was defined as LSM >or=13.4 kPa. We analysed a subgroup of patients with paired LSM and liver biopsies to validate the accuracy of LSM. RESULTS: 1466 patients had reliable LSM and 134 (9%) patients had adequate liver biopsy. 188 (13%) patients had metabolic syndrome. Histological liver cirrhosis was present in 32/134 (24%) patients. Histological liver cirrhosis was more common among patients who had metabolic syndrome (38%) versus those who did not (11%, p<0.001). The specificity of probable cirrhosis on LSM for histological cirrhosis was 94%. Probable cirrhosis was present in 187 (13%) patients. Metabolic syndrome was more prevalent in patients with probable cirrhosis (24%) than those without cirrhosis (11%, p<0.001). After adjustment for anthropometric, biochemical and virological factors, metabolic syndrome remained an independent factor associated with probable cirrhosis (odds ratio 1.7, 95% confidence interval (CI) 1.1 to 2.6). The odds ratios of probable cirrhosis were 1.4 (95% CI, 0.9 to 2.3), 2.6 (95% CI, 1.7 to 4.3), 4.1 (95% CI, 2.4 to 7.1), 4.0 (95% CI, 1.9 to 8.4) and 5.5 (95% CI, 1.8 to 16.7) in patients with one, two, three, four and five components of metabolic syndrome, respectively. CONCLUSION: Metabolic syndrome is an independent risk factor of liver cirrhosis in CHB.

Metabolic and histological features of non-alcoholic fatty liver disease patients with different serum alanine aminotransferase levels.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in affluent countries. Serum alanine aminotransferase (ALT) level is commonly performed to monitor NAFLD patients, but its clinical relevance is unclear. AIM: To evaluate the metabolic and histological features of NAFLD patients with different ALT levels. METHODS: A total of 173 consecutive patients with biopsy-proven NAFLD were studied. Patients with persistently normal ALT and those with abnormal ALT were compared. RESULTS: Patients with persistently normal ALT had lower steatosis grade than patients with abnormal ALT, but they had similar degree of lobular inflammation, ballooning and fibrosis. Among 19 patients with ALT below 0.5 times the upper limit of normal (ULN) at the time of liver biopsies, 8 (42%) and 3 (16%) had steatohepatitis and significant fibrosis respectively. The within-patient coefficient of variance was similarly high in patients with simple steatosis and steatohepatitis (33.5). Age and glucose, but not ALT, were independent factors associated with significant fibrosis. DISCUSSION: Metabolic factors, but not ALT, are associated with histological severity. Patients with ALT < 0.5 x ULN may still have non-alcoholic steatohepatitis (NASH) and significant fibrosis. Evaluation of NAFLD patients should be based on metabolic risk factors, but not ALT level.

Complete division of the radial nerve associated with a closed fracture of the humeral shaft in a child.

The management of closed fractures of the humerus with an associated nerve palsy remains controversial. With very little written about this injury in children, we present the case of a three-year-old child with a closed humeral shaft fracture in whom surgical exploration and reconstruction of the radial nerve with a sural nerve graft was performed three months after injury. The child regained full function. To the best of our knowledge, this is the first such case to be reported in the English literature.

Oncogenic osteomalacia associated with an occult phosphaturic mesenchymal tumour: clinico-radiologico-pathological correlation and ultrastructural studies.

A middle-aged man presented with bone pain at multiple sites due to tumour-induced osteomalacia. The underlying occult phosphaturic mesenchymal tumour was identified by octreotide scan 5 years after presentation and confirmed by computed tomography. Tumour resection resulted in normalisation of blood chemistry and bone densitometry. Clinico-radiologico-pathological correlation and ultrastructural studies of the tumour threw light on the pathogenesis and pathophysiology of this rare disease.